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Sample records for advanced solar array

  1. Advanced Rainbow Solar Photovoltaic Arrays

    NASA Technical Reports Server (NTRS)

    Mardesich, Nick; Shields, Virgil

    2003-01-01

    Photovoltaic arrays of the rainbow type, equipped with light-concentrator and spectral-beam-splitter optics, have been investigated in a continuing effort to develop lightweight, high-efficiency solar electric power sources. This investigation has contributed to a revival of the concept of the rainbow photovoltaic array, which originated in the 1950s but proved unrealistic at that time because the selection of solar photovoltaic cells was too limited. Advances in the art of photovoltaic cells since that time have rendered the concept more realistic, thereby prompting the present development effort. A rainbow photovoltaic array comprises side-by-side strings of series-connected photovoltaic cells. The cells in each string have the same bandgap, which differs from the bandgaps of the other strings. Hence, each string operates most efficiently in a unique wavelength band determined by its bandgap. To obtain maximum energy-conversion efficiency and to minimize the size and weight of the array for a given sunlight input aperture, the sunlight incident on the aperture is concentrated, then spectrally dispersed onto the photovoltaic array plane, whereon each string of cells is positioned to intercept the light in its wavelength band of most efficient operation. The number of cells in each string is chosen so that the output potentials of all the strings are the same; this makes it possible to connect the strings together in parallel to maximize the output current of the array. According to the original rainbow photovoltaic concept, the concentrated sunlight was to be split into multiple beams by use of an array of dichroic filters designed so that each beam would contain light in one of the desired wavelength bands. The concept has since been modified to provide for dispersion of the spectrum by use of adjacent prisms. A proposal for an advanced version calls for a unitary concentrator/ spectral-beam-splitter optic in the form of a parabolic curved Fresnel-like prism

  2. Mission applications for advanced photovoltaic solar arrays

    NASA Technical Reports Server (NTRS)

    Stella, Paul M.; West, John L.; Chave, Robert G.; Mcgee, David P.; Yen, Albert S.

    1990-01-01

    The suitability of the Advanced Photovoltaic Solar Array (APSA) for future space missions was examined by considering the impact on the spacecraft system in general. The lightweight flexible blanket array system was compared to rigid arrays and a radio-isotope thermoelectric generator (RTG) static power source for a wide range of assumed future earth orbiting and interplanetary mission applications. The study approach was to establish assessment criteria and a rating scheme, identify a reference mission set, perform the power system assessment for each mission, and develop conclusions and recommendations to guide future APSA technology development. The authors discuss the three selected power sources, the assessment criteria and rating definitions, and the reference missions. They present the assessment results in a convenient tabular format. It is concluded that the three power sources examined, APSA, conventional solar arrays, and RTGs, can be considered to complement each other. Each power technology has its own range of preferred applications.

  3. The Implementation of Advanced Solar Array Technology in Future NASA Missions

    NASA Technical Reports Server (NTRS)

    Piszczor, Michael F.; Kerslake, Thomas W.; Hoffman, David J.; White, Steve; Douglas, Mark; Spence, Brian; Jones, P. Alan

    2003-01-01

    Advanced solar array technology is expected to be critical in achieving the mission goals on many future NASA space flight programs. Current PV cell development programs offer significant potential and performance improvements. However, in order to achieve the performance improvements promised by these devices, new solar array structures must be designed and developed to accommodate these new PV cell technologies. This paper will address the use of advanced solar array technology in future NASA space missions and specifically look at how newer solar cell technologies impact solar array designs and overall power system performance.

  4. Advances in Radiation-Tolerant Solar Arrays for SEP Missions

    NASA Technical Reports Server (NTRS)

    O'Neill, Mark J.; Eskenazi, Michael I.; Ferguson, Dale C.

    2007-01-01

    As the power levels of commercial communications satellites reach the 20 kWe and higher, new options begin to emerge for transferring the satellite from LEO to GEO. In the past electric propulsion has been demonstrated successfully for this mission - albeit under unfortunate circumstances when the kick motor failed. The unexpected use of propellant for the electric propulsion (EP) system compromised the life of that vehicle, but did demonstrate the viability of such an approach. Replacing the kick motor on a satellite and replacing that mass by additional propellant for the EP system as well as mass for additional revenue-producing transponders should lead to major benefits for the provider. Of course this approach requires that the loss in solar array power during transit of the Van Allen radiation belts is not excessive and still enables the 15 to 20 year mission life. In addition, SEP missions to Jupiter, with its exceptional radiation belts, would mandate a radiation-resistant solar array to compete with a radioisotope alternative. Several critical issues emerge as potential barriers to this approach: reducing solar array radiation damage, operating the array at high voltage (>300 V) for extended times for Hall or ion thrusters, designing an array that will be resistant to micrometeoroid impacts and the differing environmental conditions as the vehicle travels from LEO to GEO (or at Jupiter), producing an array that is light weight to preserve payload mass fraction - and to do this at a cost that is lower than today's arrays. This paper will describe progress made to date on achieving an array that meets all these requirements and is also useful for deep space electric propulsion missions.

  5. Advanced Thin Film Solar Arrays for Space: The Terrestrial Legacy

    NASA Technical Reports Server (NTRS)

    Bailey, Sheila; Hepp, Aloysius; Raffaelle, Ryne; Flood, Dennis

    2001-01-01

    As in the case for single crystal solar cells, the first serious thin film solar cells were developed for space applications with the promise of better power to weight ratios and lower cost. Future science, military, and commercial space missions are incredibly diverse. Military and commercial missions encompass both hundreds of kilowatt arrays to tens of watt arrays in various earth orbits. While science missions also have small to very large power needs there are additional unique requirements to provide power for near sun missions and planetary exploration including orbiters, landers, and rovers both to the inner planets and the outer planets with a major emphasis in the near term on Mars. High power missions are particularly attractive for thin film utilization. These missions are generally those involving solar electric propulsion, surface power systems to sustain an outpost or a permanent colony on the surface of the Moon or Mars, space based lasers or radar, or large Earth orbiting power stations which can serve as central utilities for other orbiting spacecraft, or potentially beaming power to the Earth itself. This paper will discuss the current state of the art of thin film solar cells and the synergy with terrestrial thin film photovoltaic evolution. It will also address some of the technology development issues required to make thin film photovoltaics a viable choice for future space power systems.

  6. Advancements of the Lightweight Integrated Solar Array and Transceiver (LISA-T) Small Spacecraft System

    NASA Technical Reports Server (NTRS)

    Russell, Tiffany; Martinez, Armando; Boyd, Darren; SanSoucie, Michael; Farmer, Brandon; Schneider, Todd; Fabisinski, Leo; Johnson, Les; Carr, John A.

    2015-01-01

    This paper describes recent advancements of the Lightweight Integrated Solar Array and Transceiver (LISA-T) currently being developed at NASA's Marshall Space Flight Center. The LISA-T array comprises a launch stowed, orbit deployed structure on which thin-film photovoltaic (PV) and antenna devices are embedded. The system provides significant electrical power generation at low weights, high stowage efficiency, and without the need for solar tracking. Leveraging high-volume terrestrial-market PVs also gives the potential for lower array costs. LISA-T is addressing the power starvation epidemic currently seen by many small-scale satellites while also enabling the application of deployable antenna arrays. Herein, an overview of the system and its applications are presented alongside sub-system development progress and environmental testing plans/initial results.

  7. Advancements of the Lightweight Integrated Solar Array and Transceiver (LISA-T) Small Spacecraft System

    NASA Technical Reports Server (NTRS)

    Lockett, Tiffany Russell; Martinez, Armando; Boyd, Darren; SanSouice, Michael; Farmer, Brandon; Schneider, Todd; Laue, Greg; Fabisinski, Leo; Johnson, Les; Carr, John A.

    2015-01-01

    This paper describes recent advancements of the Lightweight Integrated Solar Array and Transceiver (LISA-T) currently being developed at NASA's Marshall Space Flight Center. The LISA-T array comprises a launch stowed, orbit deployed structure on which thin-film photovoltaic (PV) and antenna devices are embedded. The system provides significant electrical power generation at low weights, high stowage efficiency, and without the need for solar tracking. Leveraging high-volume terrestrial-market PVs also gives the potential for lower array costs. LISA-T is addressing the power starvation epidemic currently seen by many small-scale satellites while also enabling the application of deployable antenna arrays. Herein, an overview of the system and its applications are presented alongside sub-system development progress and environmental testing plans.

  8. Advanced Solar Cell and Array Technology for NASA Deep Space Missions

    NASA Technical Reports Server (NTRS)

    Piszczor, Michael; Benson, Scott; Scheiman, David; Finacannon, Homer; Oleson, Steve; Landis, Geoffrey

    2008-01-01

    A recent study by the NASA Glenn Research Center assessed the feasibility of using photovoltaics (PV) to power spacecraft for outer planetary, deep space missions. While the majority of spacecraft have relied on photovoltaics for primary power, the drastic reduction in solar intensity as the spacecraft moves farther from the sun has either limited the power available (severely curtailing scientific operations) or necessitated the use of nuclear systems. A desire by NASA and the scientific community to explore various bodies in the outer solar system and conduct "long-term" operations using using smaller, "lower-cost" spacecraft has renewed interest in exploring the feasibility of using photovoltaics for to Jupiter, Saturn and beyond. With recent advances in solar cell performance and continuing development in lightweight, high power solar array technology, the study determined that photovoltaics is indeed a viable option for many of these missions.

  9. Measurement of high-voltage and radiation-damage limitations to advanced solar array performance

    NASA Technical Reports Server (NTRS)

    Guidice, D. A.; Severance, P. S.; Keinhardt, K. C.

    1991-01-01

    A description is given of the reconfigured Photovoltaic Array Space Power (PASP) Plus experiment: its objectives, solar-array complement, and diagnostic sensors. Results from a successful spaceflight will lead to a better understanding of high-voltage and radiation-damage limitations in the operation of new-technology solar arrays.

  10. Solar array drive system

    NASA Technical Reports Server (NTRS)

    Berkopec, F. D.; Sturman, J. C.; Stanhouse, R. W.

    1976-01-01

    A solar array drive system consisting of a solar array drive mechanism and the corresponding solar array drive electronics is being developed. The principal feature of the solar array drive mechanism is its bidirectional capability which enables its use in mechanical redundancy. The solar array drive system is of a widely applicable design. This configuration will be tested to determine its acceptability for generic mission sets. Foremost of the testing to be performed is the testing for extended duration.

  11. High Current ESD Test of Advanced Triple Junction Solar Array Coupon

    NASA Technical Reports Server (NTRS)

    Wright, Kenneth H., Jr.; Schneider, Todd A.; Vaughn, Jason A.; Hoang, Bao; Wong, Frankie

    2015-01-01

    A test was conducted on an Advanced Triple Junction (ATJ) coupon that was part of a risk reduction effort in the development of a high-powered solar array design by SSL. The ATJ coupon was a small, 4-cell, two-string configuration that has served as the basic test coupon design used in previous SSL environmental aging campaigns. The coupon has many attributes of the flight design; e.g., substrate structure with graphite face sheets, integrated by-pass diodes, cell interconnects, RTV grout, wire routing, etc. The objective of the present test was to evaluate the performance of the coupon after being subjected to induced electrostatic discharge testing at two string voltages (100 V, 150 V) and four array current (1.65 A, 2.0 A, 2.475 A, and 3.3 A). An ESD test circuit, unique to SSL solar array design, was built that simulates the effect of missing cells and strings in a full solar panel with special primary arc flashover circuitry. A total of 73 primary arcs were obtained that included 7 temporary sustained arcs (TSA) events. The durations of the TSAs ranged from 50 micros to 2.9 ms. All TSAs occurred at a string voltage of 150 V. Post-test Large Area Pulsed Solar Simulator (LAPSS), Dark I-V, and By-Pass Diode tests showed that no degradation occurred due to the TSA events. In addition, the post-test insulation resistance measured was > 50 G-ohms between cells and substrate. These test results indicate a robust design for application to a high-current, high-power mission application.

  12. High Current ESD Test of Advanced Triple Junction Solar Array Coupon

    NASA Technical Reports Server (NTRS)

    Wright, Kenneth H., Jr.; Schneider, Todd A.; Vaughn, Jason A.; Hoang, Bao; Wong, Frankie

    2014-01-01

    Testing was conducted on an Advanced Triple Junction (ATJ) coupon that was part of a risk reduction effort in the development of a high-powered solar array design by Space Systems/Loral, LLC (SSL). The ATJ coupon was a small, 4-cell, two-string configuration that has served as the basic test coupon design used in previous SSL environmental aging campaigns. The coupon has many attributes of the flight design; e.g., substrate structure with graphite face sheets, integrated by-pass diodes, cell interconnects, RTV grout, wire routing, etc. The objective of the present test was to evaluate the performance of the coupon after being subjected to induced electrostatic discharge (ESD) testing at two string voltages (100 V, 150 V) and four array currents (1.65 A, 2.0 A, 2.475 A, and 3.3 A). An ESD test circuit, unique to SSL solar array design, was built that simulates the effect of missing cells and strings in a full solar panel with special primary arc flashover circuitry. A total of 73 primary arcs were obtained that included 7 temporary sustained arcs (TSA) events. The durations of the TSAs ranged from 50 micro-seconds to 2.75 milli-seconds. All TSAs occurred at a string voltage of 150 V. Post-test Large Area Pulsed Solar Simulator (LAPSS), Dark I-V, and By-Pass Diode tests showed that no degradation occurred due to the TSA events. In addition, the post-test insulation resistance measured was > 50 G-ohms between cells and substrate. These test results indicate a robust design for application to a high-current, high-power mission.

  13. High Current ESD Test of Advanced Triple Junction Solar Array Coupon

    NASA Technical Reports Server (NTRS)

    Wright, K. H.; Schneider, T. A.; Vaughn, J. A.; Hoang, B.; Wong, F.

    2014-01-01

    A test was conducted on an Advanced Triple Junction (ATJ) coupon that was part of a risk reduction effort in the development of a high-powered solar array design by SSL. The ATJ coupon was a small, 4-cell, two-string configuration that has served as the basic test coupon design used in previous SSL environmental aging campaigns. The coupon has many attributes of the flight design; e.g., substrate structure with graphite face sheets, integrated by-pass diodes, cell interconnects, RTV grout, wire routing, etc. The objective of the present test was to evaluate the performance of the coupon after being subjected to induced electrostatic discharge testing at two string voltages (100 V, 150 V) and four array current (1.65 A, 2.0 A, 2.475 A, and 3.3 A). An ESD test circuit, unique to SSL solar array design, was built that simulates the effect of missing cells and strings in a full solar panel with special primary arc flashover circuitry. A total of 73 primary arcs were obtained that included 7 temporary sustained arcs (TSA) events. The durations of the TSAs ranged from 50 µs to 2.9 ms. All TSAs occurred at a string voltage of 150 V. Post-test Large Area Pulsed Solar Simulator (LAPSS), Dark I-V, and By-Pass Diode tests showed that no degradation occurred due to the TSA events. In addition, the post-test insulation resistance measured was > 50 G-ohms between cells and substrate. These test results indicate a robust design for application to a high-current, high-power mission application.

  14. High Current ESD Test of Advanced Triple Junction Solar Array Coupon

    NASA Technical Reports Server (NTRS)

    Wright, Kenneth H., Jr.; Schneider, Todd A.; Vaughn, Jason A.; Hoang, Bao; Wong, Frankie

    2014-01-01

    Testing was conducted on an Advanced Triple Junction (ATJ) coupon that was part of a risk reduction effort in the development of a high-powered solar array design by Space Systems Loral, LLC (SSL). The ATJ coupon was a small, 4-cell, two-string configuration of flight-type design that has served as the basic test coupon design used in previous SSL environmental aging campaigns. The objective of the present test was to evaluate the performance of the coupon after being subjected to induced electrostatic discharge (ESD) testing at two string voltages (100 V, 150 V) and four string currents (1.65 A, 2.0 A, 2.475 A, and 3.3 A). An ESD test circuit, unique to SSL solar array design, was built that simulates the effect of missing cells and strings in a full solar panel with special primary arc flashover circuitry. A total of 73 primary arcs were obtained that included 7 temporary sustained arcs (TSA) events. The durations of the TSAs ranged from 50 micro-seconds to 2.75 milli-seconds. All TSAs occurred at a string voltage of 150 V. Post-ESD functional testing showed that no degradation occurred due to the TSA events. These test results point to a robust design for application to a high-current, high-power mission.

  15. Glory Solar Array Deployment

    NASA Video Gallery

    The Glory spacecraft uses Orbital Sciences Corporation Space Systems Group's LEOStar-1 bus design, with deployable, four-panel solar arrays. This conceptual animation reveals Glory's unique solar a...

  16. Solar array deployment mechanism

    NASA Astrophysics Data System (ADS)

    Calassa, Mark C.; Kackley, Russell

    1995-05-01

    This paper describes a Solar Array Deployment Mechanism (SADM) used to deploy a rigid solar array panel on a commercial spacecraft. The application required a deployment mechanism design that was not only lightweight, but also could be produced and installed at the lowest possible cost. This paper covers design, test, and analysis of a mechanism that meets these requirements.

  17. Solar array deployment mechanism

    NASA Technical Reports Server (NTRS)

    Calassa, Mark C.; Kackley, Russell

    1995-01-01

    This paper describes a Solar Array Deployment Mechanism (SADM) used to deploy a rigid solar array panel on a commercial spacecraft. The application required a deployment mechanism design that was not only lightweight, but also could be produced and installed at the lowest possible cost. This paper covers design, test, and analysis of a mechanism that meets these requirements.

  18. Solar collector array

    SciTech Connect

    Hall, John Champlin; Martins, Guy Lawrence

    2015-09-06

    A method and apparatus for efficient manufacture, assembly and production of solar energy. In one aspect, the apparatus may include a number of modular solar receiver assemblies that may be separately manufactured, assembled and individually inserted into a solar collector array housing shaped to receive a plurality of solar receivers. The housing may include optical elements for focusing light onto the individual receivers, and a circuit for electrically connecting the solar receivers.

  19. ISS Solar Array Management

    NASA Technical Reports Server (NTRS)

    Williams, James P.; Martin, Keith D.; Thomas, Justin R.; Caro, Samuel

    2010-01-01

    The International Space Station (ISS) Solar Array Management (SAM) software toolset provides the capabilities necessary to operate a spacecraft with complex solar array constraints. It monitors spacecraft telemetry and provides interpretations of solar array constraint data in an intuitive manner. The toolset provides extensive situational awareness to ensure mission success by analyzing power generation needs, array motion constraints, and structural loading situations. The software suite consists of several components including samCS (constraint set selector), samShadyTimers (array shadowing timers), samWin (visualization GUI), samLock (array motion constraint computation), and samJet (attitude control system configuration selector). It provides high availability and uptime for extended and continuous mission support. It is able to support two-degrees-of-freedom (DOF) array positioning and supports up to ten simultaneous constraints with intuitive 1D and 2D decision support visualizations of constraint data. Display synchronization is enabled across a networked control center and multiple methods for constraint data interpolation are supported. Use of this software toolset increases flight safety, reduces mission support effort, optimizes solar array operation for achieving mission goals, and has run for weeks at a time without issues. The SAM toolset is currently used in ISS real-time mission operations.

  20. Solar array flight experiment

    NASA Technical Reports Server (NTRS)

    1986-01-01

    Emerging satellite designs require increasing amounts of electrical power to operate spacecraft instruments and to provide environments suitable for human habitation. In the past, electrical power was generated by covering rigid honeycomb panels with solar cells. This technology results in unacceptable weight and volume penalties when large amounts of power are required. To fill the need for large-area, lightweight solar arrays, a fabrication technique in which solar cells are attached to a copper printed circuit laminated to a plastic sheet was developed. The result is a flexible solar array with one-tenth the stowed volume and one-third the weight of comparably sized rigid arrays. An automated welding process developed to attack the cells to the printed circuit guarantees repeatable welds that are more tolerant of severe environments than conventional soldered connections. To demonstrate the flight readiness of this technology, the Solar Array Flight Experiment (SAFE) was developed and flown on the space shuttle Discovery in September 1984. The tests showed the modes and frequencies of the array to be very close to preflight predictions. Structural damping, however, was higher than anticipated. Electrical performance of the active solar panel was also tested. The flight performance and postflight data evaluation are described.

  1. TRMM Solar Array Panels

    NASA Technical Reports Server (NTRS)

    1998-01-01

    This final report presents conclusions/recommendations concerning the TRMM Solar Array; deliverable list and schedule summary; waivers and deviations; as-shipped performance data, including flight panel verification matrix, panel output detail, shadow test summary, humidity test summary, reverse bias test panel; and finally, quality assurance summary.

  2. Solar array subsystems study

    NASA Technical Reports Server (NTRS)

    Richardson, P. W.; Miller, F. Q.; Badgley, M. B.

    1980-01-01

    The effects on life cycle costs of a number of technology areas are examined for a LEO, 500 kW solar array. A baseline system conceptual design is developed and the life cycle costs estimated in detail. The baseline system requirements and design technologies are then varied and their relationships to life cycle costs quantified. For example, the thermal characteristics of the baseline design are determined by the array materials and masses. The thermal characteristics in turn determine configuration, performance and hence life cycle cost.

  3. Rigid Solar Generator (GSR) solar arrays

    NASA Astrophysics Data System (ADS)

    Martin, G. A.; Laget, R.; Urbain, G.; Bastard, J. L.

    The Telecom, TV-SAT, and ARABSAT solar arrays are described. The Telecom minimal power requirement of 110 W during the spinned transfer phase (solar array stowed on the spacecraft walls) and 1054 W summer solstice on orbit (3 axis stabilized), led to a 3 panels per wing solar array with panel dimensions of 1295.4 x 2047 mm. The TV-SAT and ARABSAT arrays differ from Telecom by their partial deployment in transfer orbit. The arrays contain 14,256 solar cells for primary power and 1560 cells for battery charging. Cells are 180 micron thick back surface reflectors.

  4. Mir Cooperative Solar Array

    NASA Technical Reports Server (NTRS)

    Skor, Mike; Hoffman, Dave J.

    1997-01-01

    The Mir Cooperative Solar Array (MCSA), produced jointly by the United States and Russia, was deployed on the Mir Russian space station on May 25, 1996. The MCSA is a photovoltaic electrical power system that can generate up to 6 kW. The power from the MCSA is needed to extend Mir's lifetime and to support experiments conducted there by visiting U.S. astronauts. The MCSA was brought to Mir via the Space Shuttle Atlantis on the STS-74 mission, launched November 12, 1995. This cooperative venture combined the best technology of both countries: the United States provided high-efficiency, lightweight photovoltaic panel modules, whereas Russia provided the array structure and deployment mechanism. Technology developed in the Space Station Freedom Program, and now being used in the International Space Station, was used to develop MCSA's photovoltaic panel. Performance data obtained from MCSA operation on Mir will help engineers better understand the performance of the photovoltaic panel modules in orbit. This information will be used to more accurately predict the performance of the International Space Station solar arrays. Managed by the NASA Lewis Research Center for NASA's International Space Station Program Office in Houston, Texas, the MCSA Project was completed on time and under budget despite a very aggressive schedule.

  5. Solar array construction

    DOEpatents

    Crouthamel, Marvin S.; Coyle, Peter J.

    1982-01-01

    An interconnect tab on each cell of a first set of circular solar cells connects that cell in series with an adjacent cell in the set. This set of cells is arranged in alternate columns and rows of an array and a second set of similar cells is arranged in the remaining alternate columns and rows of the array. Three interconnect tabs on each solar cell of the said second set are employed to connect the cells of the second set to one another, in series and to connect the cells of the second set to those of the first set in parallel. Some tabs (making parallel connections) connect the same surface regions of adjacent cells to one another and others (making series connections) connect a surface region of one cell to the opposite surface region of an adjacent cell; however, the tabs are so positioned that the array may be easily assembled by depositing the cells in a certain sequence and in proper orientation.

  6. Electromagnetically Clean Solar Arrays

    NASA Technical Reports Server (NTRS)

    Stem, Theodore G.; Kenniston, Anthony E.

    2008-01-01

    The term 'electromagnetically clean solar array' ('EMCSA') refers to a panel that contains a planar array of solar photovoltaic cells and that, in comparison with a functionally equivalent solar-array panel of a type heretofore used on spacecraft, (1) exhibits less electromagnetic interferences to and from other nearby electrical and electronic equipment and (2) can be manufactured at lower cost. The reduction of electromagnetic interferences is effected through a combination of (1) electrically conductive, electrically grounded shielding and (2) reduction of areas of current loops (in order to reduce magnetic moments). The reduction of cost is effected by designing the array to be fabricated as a more nearly unitary structure, using fewer components and fewer process steps. Although EMCSAs were conceived primarily for use on spacecraft they are also potentially advantageous for terrestrial applications in which there are requirements to limit electromagnetic interference. In a conventional solar panel of the type meant to be supplanted by an EMCSA panel, the wiring is normally located on the back side, separated from the cells, thereby giving rise to current loops having significant areas and, consequently, significant magnetic moments. Current-loop geometries are chosen in an effort to balance opposing magnetic moments to limit far-0field magnetic interactions, but the relatively large distances separating current loops makes full cancellation of magnetic fields problematic. The panel is assembled from bare photovoltaic cells by means of multiple sensitive process steps that contribute significantly to cost, especially if electomagnetic cleanliness is desired. The steps include applying a cover glass and electrical-interconnect-cell (CIC) sub-assemble, connecting the CIC subassemblies into strings of series-connected cells, laying down and adhesively bonding the strings onto a panel structure that has been made in a separate multi-step process, and mounting the

  7. High Voltage Space Solar Arrays

    NASA Technical Reports Server (NTRS)

    Ferguson, D. C.; Hillard, G. B.; Vayner, B. V.; Galofaro, J. T.; Lyons, Valerie (Technical Monitor)

    2002-01-01

    Recent tests performed at the NASA Glenn Research Center and elsewhere have shown promise in the design and construction of high voltage (300-1000 V) solar arrays for space applications. Preliminary results and implications for solar array design will be discussed, with application to direct-drive electric propulsion and space solar power.

  8. NASA Solar Array Demonstrates Commercial Potential

    NASA Technical Reports Server (NTRS)

    Creech, Gray

    2006-01-01

    A state-of-the-art solar-panel array demonstration site at NASA's Dryden Flight Research Center provides a unique opportunity for studying the latest in high-efficiency solar photovoltaic cells. This five-kilowatt solar-array site (see Figure 1) is a technology-transfer and commercialization success for NASA. Among the solar cells at this site are cells of a type that was developed in Dryden Flight Research Center s Environmental Research Aircraft and Sensor Technology (ERAST) program for use in NASA s Helios solar-powered airplane. This cell type, now denoted as A-300, has since been transferred to SunPower Corporation of Sunnyvale, California, enabling mass production of the cells for the commercial market. High efficiency separates these advanced cells from typical previously commercially available solar cells: Whereas typical previously commercially available cells are 12 to 15 percent efficient at converting sunlight to electricity, these advanced cells exhibit efficiencies approaching 23 percent. The increase in efficiency is due largely to the routing of electrical connections behind the cells (see Figure 2). This approach to increasing efficiency originated as a solution to the problem of maximizing the degree of utilization of the limited space available atop the wing of the Helios airplane. In retrospect, the solar cells in use at this site could be used on Helios, but the best cells otherwise commercially available could not be so used, because of their lower efficiencies. Historically, solar cells have been fabricated by use of methods that are common in the semiconductor industry. One of these methods includes the use of photolithography to define the rear electrical-contact features - diffusions, contact openings, and fingers. SunPower uses these methods to produce the advanced cells. To reduce fabrication costs, SunPower continues to explore new methods to define the rear electrical-contact features. The equipment at the demonstration site includes

  9. Solar electric propulsion thruster interactions with solar arrays

    NASA Technical Reports Server (NTRS)

    Parks, D. E.; Katz, I.

    1977-01-01

    The effect of interactions of spacecraft-generated and naturally occurring plasmas with high voltage solar array components on an advanced solar electric propulsion system proposed for the Halley's Comet rendezvous mission was investigated. The spacecraft-generated plasma consists of mercury ions and neutralizing electrons resulting from the operation of ion thrusters (the charge-exchange plasma) and associated hollow cathode neutralizers. Quantitative results are given for the parasitic currents and power coupled into solar arrays with voltage fixed as a function of position on the array.

  10. Advanced solar panel designs

    NASA Technical Reports Server (NTRS)

    Ralph, E. L.; Linder, E.

    1995-01-01

    This paper describes solar cell panel designs that utilize new hgih efficiency solar cells along with lightweight rigid panel technology. The resulting designs push the W/kg and W/sq m parameters to new high levels. These new designs are well suited to meet the demand for higher performance small satellites. This paper reports on progress made on two SBIR Phase 1 contracts. One panel design involved the use of large area (5.5 cm x 6.5 cm) GaAs/Ge solar cells of 19% efficiency combined with a lightweight rigid graphite fiber epoxy isogrid substrate configuration. A coupon (38 cm x 38 cm) was fabricated and tested which demonstrated an array specific power level of 60 W/kg with a potential of reaching 80 W/kg. The second panel design involved the use of newly developed high efficiency (22%) dual junction GaInP2/GaAs/Ge solar cells combined with an advanced lightweight rigid substrate using aluminum honeycomb core with high strength graphite fiber mesh facesheets. A coupon (38 cm x 38 cm) was fabricated and tested which demonstrated an array specific power of 105 W/kg and 230 W/sq m. This paper will address the construction details of the panels and an a analysis of the component weights. A strawman array design suitable for a typical small-sat mission is described for each of the two panel design technologies being studied. Benefits in respect to weight reduction, area reduction, and system cost reduction are analyzed and compared to conventional arrays.

  11. LSA Low-cost Solar Array project

    NASA Technical Reports Server (NTRS)

    1978-01-01

    The activities of the Low-Cost Silicon Solar Array Project during the period October through December, 1977 are reported. The LSSA Project is assigned responsibility for advancing silicon solar array technology while encouraging industry to reduce the price of arrays to a level at which photovoltaic electric power systems will be competitive with more conventional power sources early in the next decade. Set forth are the goals and plans with which the Project intends to accomplish this and the progress that was made during the quarter.

  12. Low-cost Solar Array (LSA) project

    NASA Technical Reports Server (NTRS)

    1978-01-01

    The activities of the Low-Cost Solar Array Project are described for the period April through June 1978. The Project is assigned responsibility for advancing solar array technology while encouraging industry to reduce the price of arrays to a level at which photovoltaic electric power systems will be competitive with more conventional power sources early in the next decade. Set forth are the goals and plans with which the Project intends to accomplish this and the progress that was made during the quarter.

  13. PEP solar array definition study

    NASA Technical Reports Server (NTRS)

    1979-01-01

    The conceptual design of a large, flexible, lightweight solar array is presented focusing on a solar array overview assessment, solar array blanket definition, structural-mechanical systems definition, and launch/reentry blanket protection features. The overview assessment includes a requirements and constraints review, the thermal environment assessment on the design selection, an evaluation of blanket integration sequence, a conceptual blanket/harness design, and a hot spot analysis considering the effects of shadowing and cell failures on overall array reliability. The solar array blanket definition includes the substrate design, hinge designs and blanket/harness flexibility assessment. The structural/mechanical systems definition includes an overall loads and deflection assessment, a frequency analysis of the deployed assembly, a components weights estimate, design of the blanket housing and tensioning mechanism. The launch/reentry blanket protection task includes assessment of solar cell/cover glass cushioning concepts during ascent and reentry flight condition.

  14. SMEX-Lite Modular Solar Array Architecture

    NASA Technical Reports Server (NTRS)

    Lyons, John

    2002-01-01

    similarity to multiple missions. It then becomes possible to procure solar array modules in advance of mission definition and respond quickly and inexpensively to a selected mission's unique requirements. The solar array modular architecture allows the procurement of solar array modules before the array geometry has been frozen. This reduces the effect of procurement lead-time on the mission integration and test flow by as much as 50%. Second, by spreading the non-recurring costs over multiple missions, the cost per unit area is also reduced. In the case of the SMEX-Lite procurement, this reduction was by about one third of the cost per unit area compared to previous SMEX mission-unique procurements. Third, the modular architecture greatly facilitates the infusion of new solar cell technologies into flight programs as these technologies become available. New solar cell technologies need only be fabricated onto a standard-sized module to be incorporated into the next available mission. The modular solar array can be flown in a mixed configuration with some new and some standard cell technologies. Since each module has its own wiring terminals, the array can be arranged as desired electrically with little impact to cost and schedule. The solar array modular architecture does impose some additional constraints on systems and subsystem engineers. First, they must work with discrete solar array modules rather than size the array to fit exactly within an available envelope. The array area is constrained to an integer multiple of the module area. Second, the modular design is optimized for space radiation and thermal environments not greatly different from a typical SMEX LEO environment. For example, a mission with a highly elliptical orbit (e.g., Polar, SMEX/FAST) would require thicker coverglasses to protect the solar cells from the more intense radiation environment.

  15. Solar Array Tracking Control

    1995-06-22

    SolarTrak used in conjunction with various versions of 68HC11-based SolarTrack hardware boards provides control system for one or two axis solar tracking arrays. Sun position is computed from stored position data and time from an on-board clock/calendar chip. Position feedback can be by one or two offset motor turn counter square wave signals per axis, or by a position potentiometer. A limit of 256 counts resolution is imposed by the on-board analog to digital (A/D)more » convertor. Control is provided for one or two motors. Numerous options are provided to customize the controller for specific applications. Some options are imposed at compile time, some are setable during operation. Software and hardware board designs are provided for Control Board and separate User Interface Board that accesses and displays variables from Control Board. Controller can be used with range of sensor options ranging from a single turn count sensor per motor to systems using dual turn-count sensors, limit sensors, and a zero reference sensor. Dual axis trackers oriented azimuth elevation, east west, north south, or polar declination can be controlled. Misalignments from these orientations can also be accommodated. The software performs a coordinate transformation using six parameters to compute sun position in misaligned coordinates of the tracker. Parameters account for tilt of tracker in two directions, rotation about each axis, and gear ration errors in each axis. The software can even measure and compute these prameters during an initial setup period if current from a sun position sensor or output from photovoltaic array is available as an anlog voltage to the control board''s A/D port. Wind or emergency stow to aj present position is available triggered by digital or analog signals. Night stow is also available. Tracking dead band is adjustable from narrow to wide. Numerous features of the hardware and software conserve energy for use with battery powered systems.« less

  16. TRMM Solar Array

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Basic requirement of 978.59 watts per Panel output @ 58.9 volts B.O.L. was met on an average basis per agreement with NASA. Lower grade Cells were used on the shadowed Panel (Boom shadow) to maximize available power to the Spacecraft. The average output @ 58.9 volts was 991 watts. The outputs of the four t4) Panels ranged from 960 to 1,022 watts. The Panels successfully passed environmental testing at TRW to the contract specification and subsequent testing at NASA which involved output measurements at elevated temperatures. As this type of Array had never previously been built by TRW (aluminum Substrate with 4 cm x 4.4 cm GaAs Cells), the TRMM Program was a development effort combined with a Qual and Flight production effort. The most significant technical problem was Cell cracking during Qual thermal cycling. The cracking problem was determined to be generic within our Solar Array factory in the application of GaAs Cells to our designs. As a result, a TRW funded manufacturing process verification panel (known as the Manufacturing Verification Panel) was built to demonstrate our ability to properly apply GaAs Cells. The original Qual Panel comprised three (3) design variations with respect to Coverglass-to-Cell and Cell-to-Substrate adhesives. The intent was to qualify multiple designs in case one or more failed. When two of the three combinations failed due to excessive Cell breakage during thermal cycling, NASA was reluctant to allow Flight production based on the one remaining good Qual Panel Quadrant. This issue was pivotal for continuing the contract. Facts and recommendations are as follows: (1) The cause of the excessive cracking was never determined. and (2) The areas where the excessive cracking occurred utilized DC93-500 glassing adhesive which was NASA approved, and had been widely used by TRW on a multitude of projects.

  17. Flexible solar-array mechanism

    NASA Technical Reports Server (NTRS)

    Olson, M. C.

    1972-01-01

    One of the key elements of the flexible rolled-up solar array system is a mechanism to deploy, retract, and store the flexible solar-cell arrays. The selection of components, the design of the mechanism assembly, and the tests that were performed are discussed. During 6 months in orbit, all mission objectives were satisfied, and inflight performance has shown good correlation with preflight analyses and tests.

  18. Method for forming a solar array strip

    NASA Technical Reports Server (NTRS)

    Mueller, R. I.; Yasui, R. K. (Inventor)

    1979-01-01

    A flexible solar array strip is formed by a method which lends itself to automatic production techniques. Solder pads are deposited on printed circuitry deposited on a flexible structure. The resultant substrate is stored on a drum from which it is withdrawn and incrementally advanced along a linear path. Solderless solar cells are serially transported into engagement with the pads which are then heated in order to attach the cells to the circuitry. Excess flux is cleaned from the cells which are encapsulated in a protective coating. The resultant array is then spirally wound on a drum.

  19. Wafer-Scale Integration of Inverted Nanopyramid Arrays for Advanced Light Trapping in Crystalline Silicon Thin Film Solar Cells.

    PubMed

    Zhou, Suqiong; Yang, Zhenhai; Gao, Pingqi; Li, Xiaofeng; Yang, Xi; Wang, Dan; He, Jian; Ying, Zhiqin; Ye, Jichun

    2016-12-01

    Crystalline silicon thin film (c-Si TF) solar cells with an active layer thickness of a few micrometers may provide a viable pathway for further sustainable development of photovoltaic technology, because of its potentials in cost reduction and high efficiency. However, the performance of such cells is largely constrained by the deteriorated light absorption of the ultrathin photoactive material. Here, we report an efficient light-trapping strategy in c-Si TFs (~20 μm in thickness) that utilizes two-dimensional (2D) arrays of inverted nanopyramid (INP) as surface texturing. Three types of INP arrays with typical periodicities of 300, 670, and 1400 nm, either on front, rear, or both surfaces of the c-Si TFs, are fabricated by scalable colloidal lithography and anisotropic wet etch technique. With the extra aid of antireflection coating, the sufficient optical absorption of 20-μm-thick c-Si with a double-sided 1400-nm INP arrays yields a photocurrent density of 39.86 mA/cm(2), which is about 76 % higher than the flat counterpart (22.63 mA/cm(2)) and is only 3 % lower than the value of Lambertian limit (41.10 mA/cm(2)). The novel surface texturing scheme with 2D INP arrays has the advantages of excellent antireflection and light-trapping capabilities, an inherent low parasitic surface area, a negligible surface damage, and a good compatibility for subsequent process steps, making it a good alternative for high-performance c-Si TF solar cells. PMID:27071681

  20. Wafer-Scale Integration of Inverted Nanopyramid Arrays for Advanced Light Trapping in Crystalline Silicon Thin Film Solar Cells.

    PubMed

    Zhou, Suqiong; Yang, Zhenhai; Gao, Pingqi; Li, Xiaofeng; Yang, Xi; Wang, Dan; He, Jian; Ying, Zhiqin; Ye, Jichun

    2016-12-01

    Crystalline silicon thin film (c-Si TF) solar cells with an active layer thickness of a few micrometers may provide a viable pathway for further sustainable development of photovoltaic technology, because of its potentials in cost reduction and high efficiency. However, the performance of such cells is largely constrained by the deteriorated light absorption of the ultrathin photoactive material. Here, we report an efficient light-trapping strategy in c-Si TFs (~20 μm in thickness) that utilizes two-dimensional (2D) arrays of inverted nanopyramid (INP) as surface texturing. Three types of INP arrays with typical periodicities of 300, 670, and 1400 nm, either on front, rear, or both surfaces of the c-Si TFs, are fabricated by scalable colloidal lithography and anisotropic wet etch technique. With the extra aid of antireflection coating, the sufficient optical absorption of 20-μm-thick c-Si with a double-sided 1400-nm INP arrays yields a photocurrent density of 39.86 mA/cm(2), which is about 76 % higher than the flat counterpart (22.63 mA/cm(2)) and is only 3 % lower than the value of Lambertian limit (41.10 mA/cm(2)). The novel surface texturing scheme with 2D INP arrays has the advantages of excellent antireflection and light-trapping capabilities, an inherent low parasitic surface area, a negligible surface damage, and a good compatibility for subsequent process steps, making it a good alternative for high-performance c-Si TF solar cells.

  1. Mass properties survey of solar array technologies

    NASA Technical Reports Server (NTRS)

    Kraus, Robert

    1991-01-01

    An overview of the technologies, electrical performance, and mass characteristics of many of the presently available and the more advanced developmental space solar array technologies is presented. Qualitative trends and quantitative mass estimates as total array output power is increased from 1 kW to 5 kW at End of Life (EOL) from a single wing are shown. The array technologies are part of a database supporting an ongoing solar power subsystem model development for top level subsystem and technology analyses. The model is used to estimate the overall electrical and thermal performance of the complete subsystem, and then calculate the mass and volume of the array, batteries, power management, and thermal control elements as an initial sizing. The array types considered here include planar rigid panel designs, flexible and rigid fold-out planar arrays, and two concentrator designs, one with one critical axis and the other with two critical axes. Solar cell technologies of Si, GaAs, and InP were included in the analyses. Comparisons were made at the array level; hinges, booms, harnesses, support structures, power transfer, and launch retention mountings were included. It is important to note that the results presented are approximations, and in some cases revised or modified performance and mass estimates of specific designs.

  2. Thin, Flexible IMM Solar Array

    NASA Technical Reports Server (NTRS)

    Walmsley, Nicholas

    2015-01-01

    NASA needs solar arrays that are thin, flexible, and highly efficient; package compactly for launch; and deploy into large, structurally stable high-power generators. Inverted metamorphic multijunction (IMM) solar cells can enable these arrays, but integration of this thin crystalline cell technology presents certain challenges. The Thin Hybrid Interconnected Solar Array (THINS) technology allows robust and reliable integration of IMM cells into a flexible blanket comprising standardized modules engineered for easy production. The modules support the IMM cell by using multifunctional materials for structural stability, shielding, coefficient of thermal expansion (CTE) stress relief, and integrated thermal and electrical functions. The design approach includes total encapsulation, which benefits high voltage as well as electrostatic performance.

  3. High voltage solar array experiments

    NASA Technical Reports Server (NTRS)

    Kennerud, K. L.

    1974-01-01

    The interaction between the components of a high voltage solar array and a simulated space plasma is studied to obtain data for the design of a high voltage solar array capable of 15kW at 2 to 16kV. Testing was conducted in a vacuum chamber 1.5-m long by 1.5-m diameter having a plasma source which simulated the plasma conditions existing in earth orbit between 400 nautical miles and synchronous altitude. Test samples included solar array segments pinholes in insulation covering high voltage electrodes, and plain dielectric samples. Quantitative data are presented in the areas of plasma power losses, plasma and high voltage induced damage, and dielectric properties. Limitations of the investigation are described.

  4. Multipurpose Communication Satellite solar array

    NASA Astrophysics Data System (ADS)

    Bastard, J. L.; Guyot, Ph.

    Through research and development studies, Aerospatiale has developed with the French National Space Agency (CNES) a new concept of a rigid Solar Array (GSR) which covers a range of power between 1 kW and 10 kW EOL 7 yr. This technology is used by Aerospatiale on the currently running programs:—TELECOM 1, Telecommunication satellite, spinned in transfer; —ARABSAT, Telecommunication satellite, 3-axis stabilized in transfer; —TELE-X and TV-SAT/TDF1, Direct Broadcasting satellites, 3-axis stabilized in transfer. This paper deals with the description and the electrical and mechanical performance of the Multipurpose Communication Satellite Solar Array (M.C.S.). For this satellite, which is expected to be launched in 1984, Aerospatiale has selected the following concept: primary power (1.4 kW EOL 7 yr) will be provided by two separate sun-oriented solar array wings equipped with AEG Telefunken BSR (Back Surface Reflector) solar cells. This solar generator is directly derived from the GSR technology. Owing to the three-axis stabilization of the satellite and the partial deployment of the solar array during the transfer phase it has been necessary to use a primary and a secondary hold-down devices. In the same way the position of the shunt on the solar generator induced an increase of the mass, because of the supplementary hold-down point and of the support structure. Now scribing Laser System leads to the optimization of the solar cells dimensions and allows a better fill factor of the panels and so an increase of the power performance. Beside the M.C.S concept which is fully adapted as regards its mission specifications, it was interesting to present different concepts of solar generators optimized not only as regards mass budget but also power budget. These concepts covering a large range of powers are fully adapted to telecommunication missions.

  5. Solar cell array interconnects

    DOEpatents

    Carey, Paul G.; Thompson, Jesse B.; Colella, Nicolas J.; Williams, Kenneth A.

    1995-01-01

    Electrical interconnects for solar cells or other electronic components using a silver-silicone paste or a lead-tin (Pb-Sn) no-clean fluxless solder cream, whereby the high breakage of thin (<6 mil thick) solar cells using conventional solder interconnect is eliminated. The interconnects of this invention employs copper strips which are secured to the solar cells by a silver-silicone conductive paste which can be used at room temperature, or by a Pb-Sn solder cream which eliminates undesired residue on the active surfaces of the solar cells. Electrical testing using the interconnects of this invention has shown that no degradation of the interconnects developed under high current testing, while providing a very low contact resistance value.

  6. Solar cell array interconnects

    DOEpatents

    Carey, P.G.; Thompson, J.B.; Colella, N.J.; Williams, K.A.

    1995-11-14

    Electrical interconnects are disclosed for solar cells or other electronic components using a silver-silicone paste or a lead-tin (Pb-Sn) no-clean fluxless solder cream, whereby the high breakage of thin (<6 mil thick) solar cells using conventional solder interconnect is eliminated. The interconnects of this invention employs copper strips which are secured to the solar cells by a silver-silicone conductive paste which can be used at room temperature, or by a Pb-Sn solder cream which eliminates undesired residue on the active surfaces of the solar cells. Electrical testing using the interconnects of this invention has shown that no degradation of the interconnects developed under high current testing, while providing a very low contact resistance value. 4 figs.

  7. The Stardust solar array

    NASA Technical Reports Server (NTRS)

    Gasner, S.; Sharmit, K.; Stella, P. M.; Craig, C.; Mumaw, S.

    2003-01-01

    The Stardust program, part of NASA's Discovery Missions was launched on February 7. 1999. It's seven-year mission is to gather interstellar dust and material from the comet Wild-2 and return the material to earth in January 2006. In order to accomplish this mission, the satellite will orbit the sun a total of three times, traversing distances from a little under 1 AU to 2.7 AU. On April 18 2002 , the Stardust spacecraft reached its furthest distance and broke the record for being the farthest spacecraft from the sun powered by solar energy, The Stardust solar panels were built with standard off the shelf 10 Ohm-cm high efficiency silicon solar cells. These solar cells are relatively inexpensive and have shown excellent characteristics under LILT conditions. In order to accommodate the varying temperature and intensity conditions on the electrical power subsystem, an electronic switch box was designed to reconfigure the string length and number of swings depending on the mission phase. This box allowed the use of an inexpensive direct energy transfer system for the electrical power system architecture. The solar panels and electrical power system have met all requirements. Telemetry data from the solar panels at 2.7 AU are in excellent agreement with flight predictions.

  8. Soldered solar arrays

    NASA Astrophysics Data System (ADS)

    Allen, H. C.

    1982-06-01

    The ability of soldered interconnects to withstand a combination of long life and severe environmental conditions was investigated. Improvements in joint life from the use of solder mixes appropriate to low temperature conditons were studied. Solder samples were placed in a 150 C oven for 5 weeks (= 12 yr at 80 C, or 24 at 70 C according to Arrhenius's rule). Conventional and high solder melting point array samples underwent 1000 thermal cycles between -186 and 100 C. Results show that conventional and lead rich soldered arrays can survive 10 yr geostationary orbit missions.

  9. Advanced solar space missions

    NASA Technical Reports Server (NTRS)

    Bohlin, J. D.

    1979-01-01

    The space missions in solar physics planned for the next decade are similar in that they will have, for the most part, distinct, unifying science objectives in contrast to the more general 'exploratory' nature of the Orbiting Solar Observatory and Skylab/ATM missions of the 1960's and 70's. In particular, the strategy for advanced solar physics space missions will focus on the quantitative understanding of the physical processes that create and control the flow of electromagnetic and particulate energy from the sun and through interplanetary space at all phases of the current sunspot cycle No. 21. Attention is given to the Solar Maximum Mission, the International Solar Polar Mission, solar physics on an early Shuttle mission, principal investigator class experiments for future spacelabs, the Solar Optical Telescope, the Space Science Platform, the Solar Cycle and Dynamics Mission, and an attempt to send a spacecraft to within 4 solar radii of the sun's surface.

  10. A lightweight inflatable solar array

    SciTech Connect

    Malone, P.K.; Williams, G.T.

    1995-12-31

    L`Garde and Phillips Laboratory have developed a light weight deployable solar array wing in the 200-1000 watt range, on the Inflatable Torus Solar Array Technology Demonstration (ITSAT Demo) Project. The power density of a flight unit could be as high as 93 W/kg for a 200 Watt-class wing, including structure and deployment mechanisms. In Phase 1, a proof of concept torus and array was constructed and deployed in the laboratory. During Phase 2, a revised torus and array were constructed and tested at L`Garde and the Naval Research Lab. The qualification tests included random vibration, deployment in a thermal vacuum chamber, natural frequency determination, and thermal cycling. The flight design uses 2 mil thick crystalline Si cells on an AO protected flexible Kapton film substrate folded accordion style for stowage. The support structure is a rectangular frame comprised of two inflated then rigidized cylinders, the array stowage box and its cover. The cylinders, flattened, folded and stored for launch, are deployed by inflating with N{sub 2} and rigidized by straining the cylinder laminate material controllably beyond the elastic limit. The engineering protoflight array was designed for optimum power density but, due to availability, some of the components came from excess production runs. Because of this, the actual power density of the test article was 59 W/kg, or 36% less than the baseline flight array. However, using components as designed, the projected 93 w/kg can be achieved. Due to simple deployment mechanism, the cost of an ITSAT-type solar array is about one-half that of competing systems.

  11. Solar array flight dynamic experiment

    NASA Technical Reports Server (NTRS)

    Schock, R. W.

    1986-01-01

    The purpose of the Solar Array Flight Dynamic Experiment (SAFDE) is to demonstrate the feasibility of on-orbit measurement and ground processing of large space structures dynamic characteristics. Test definition or verification provides the dynamic characteristic accuracy required for control systems use. An illumination/measurement system was developed to fly on space shuttle flight STS-31D. The system was designed to dynamically evaluate a large solar array called the Solar Array Flight Experiment (SAFE) that had been scheduled for this flight. The SAFDE system consisted of a set of laser diode illuminators, retroreflective targets, an intelligent star tracker receiver and the associated equipment to power, condition, and record the results. In six tests on STS-41D, data was successfully acquired from 18 retroreflector targets and ground processed, post flight, to define the solar array's dynamic characteristic. The flight experiment proved the viability of on-orbit test definition of large space structures dynamic characteristics. Future large space structures controllability should be greatly enhanced by this capability.

  12. Solar array flight dynamic experiment

    NASA Technical Reports Server (NTRS)

    Schock, Richard W.

    1987-01-01

    The purpose of the Solar Array Flight Dynamic Experiment (SAFDE) is to demonstrate the feasibility of on-orbit measurement and ground processing of large space structures' dynamic characteristics. Test definition or verification provides the dynamic characteristic accuracy required for control systems use. An illumination/measurement system was developed to fly on space shuttle flight STS-41D. The system was designed to dynamically evaluate a large solar array called the Solar Array Flight Experiment (SAFE) that had been scheduled for this flight. The SAFDE system consisted of a set of laser diode illuminators, retroreflective targets, an intelligent star tracker receiver and the associated equipment to power, condition, and record the results. In six tests on STS-41D, data was successfully acquired from 18 retroreflector targets and ground processed, post flight, to define the solar array's dynamic characteristic. The flight experiment proved the viability of on-orbit test definition of large space structures dynamic characteristics. Future large space structures controllability should be greatly enhanced by this capability.

  13. Low cost silicon solar arrays

    NASA Technical Reports Server (NTRS)

    Goldsmith, J. V.; Cleland, J. W.; Westbrook, R. D.; Davis, H. L.; Wood, R. F.; Lindmayer, J.; Wakefield, G. F.

    1975-01-01

    The economic production of silicon solar cell arrays circumvents p-n junction degradation by nuclear doping, in which the Si-30 transmutes to P-31 after thermal neutron capture. Also considered are chemical purity specifications for improved silicon bulk states, surface induced states, and surface states.

  14. Retrieval of Mir Solar Array

    NASA Technical Reports Server (NTRS)

    Rutledge, Sharon K.; deGroh, Kim K.

    1999-01-01

    A Russian solar array panel removed in November 1997 from the non-articulating photovoltaic array on the Mir core module was returned to Earth on STS-89 in January 1998. The panel had been exposed to low Earth orbit (LEO) for 10 years prior to retrieval. The retrieval provided a unique opportunity to study the effects of the LEO environment on a functional solar array. To take advantage of this opportunity, a team composed of members from RSC-Energia (Russia), the Boeing Company, and the following NASA Centers--Johnson Space Center, Kennedy Space Center, Langley Research Center, Marshall Space Flight Center, and Lewis Research Center--was put together to analyze the array. After post-retrieval inspections at the Spacehab Facility at Kennedy in Florida, the array was shipped to Lewis in Cleveland for electrical performance tests, closeup photodocumentation, and removal of selected solar cells and blanket material. With approval from RSC-Energia, five cell pairs and their accompanying blanket and mesh material, and samples of painted handrail materials were selected for removal on the basis of their ability to provide degradation information. Sites were selected that provided different sizes and shapes of micrometeoroid impacts and different levels of surface contamination. These materials were then distributed among the team for round robin testing.

  15. Photoelectric solar cell array

    SciTech Connect

    Lidorenko, N.S.; Afian, V.V.; Martirosian, R.G.; Ryabikov, S.V.; Strebkov, D.S.; Vartanian, A.V.

    1983-11-29

    A photoelectric solar cell device comprises a dispersing element exposed to the sun's radiation and followed in the optical path by photocells having different spectral sensitivities. Each photocell has its working surface so oriented that the light beam with the wavelength corresponding to the maximum spectral sensitivity of that photocell impinges on its working surface. The dispersing element is a hologram representing light sources with different wavelengths. The photocells are positioned in the image planes of the light sources producing the light beams of the corresponding wavelengths.

  16. Advances in Small Pixel TES-Based X-Ray Microcalorimeter Arrays for Solar Physics and Astrophysics

    NASA Technical Reports Server (NTRS)

    Bandler, S. R.; Adams, J. S.; Bailey, C. N.; Busch, S. E.; Chervenak, J. A.; Eckart, M. E.; Ewin, A. E.; Finkbeiner, F. M.; Kelley, R. L.; Kelly, D. P.; Kilbourne, C. A.; Porst, J.-P.; Porter, F. S.; Sadleir, J. E.; Smith, S. J.; Wassell, E. J.

    2012-01-01

    We are developing small-pixel transition-edge-sensor (TES) for solar physics and astrophysics applications. These large format close-packed arrays are fabricated on solid silicon substrates and are designed to accommodate count-rates of up to a few hundred counts/pixel/second at a FWHM energy resolution approximately 2 eV at 6 keV. We have fabricated versions that utilize narrow-line planar and stripline wiring. We present measurements of the performance and uniformity of kilo-pixel arrays, incorporating TESs with single 65-micron absorbers on a 7s-micron pitch, as well as versions with more than one absorber attached to the TES, 4-absorber and 9-absorber "Hydras". We have also fabricated a version of this detector optimized for lower energies and lower count-rate applications. These devices have a lower superconducting transition temperature and are operated just above the 40mK heat sink temperature. This results in a lower heat capacity and low thermal conductance to the heat sink. With individual single pixels of this type we have achieved a FWHM energy resolution of 0.9 eV with 1.5 keV Al K x-rays, to our knowledge the first x-ray microcalorimeter with sub-eV energy resolution. The 4-absorber and 9-absorber versions of this type achieved FWHM energy resolutions of 1.4 eV and 2.1 eV at 1.5 keV respectively. We will discuss the application of these devices for new astrophysics mission concepts.

  17. International ultraviolet explorer solar array power degradation

    NASA Astrophysics Data System (ADS)

    Day, J. H., Jr.

    1983-01-01

    The characteristic electrical performance of each International Ultraviolet Explorer (IUE) solar array panel is evaluated as a function of several prevailing variables (namely, solar illumination, array temperature and solar cell radiation damage). Based on degradation in the current-voltage characteristics of the array due to solar cell damage accumulated over time by space charged particle radiations, the available IUE solar array power is determined for life goals up to 10 years. Best and worst case calculations are normalized to actual IUE flight data (available solar array power versus observatory position) to accurately predict the future IUE solar array output. It is shown that the IUE solar array can continue to produce more power than is required at most observatory positions for at least 5 more years.

  18. PEP solar array definition study

    NASA Technical Reports Server (NTRS)

    1979-01-01

    The power extension package (PEP) is a solar array system that will be used on the space transportation system to augment the power of the Orbiter vehicle and to extend the time the vehicle may stay in orbit. The baseline configuration of the PEP is reviewed. The programmatic aspects of the design covering the development plan, the manufacturing facility plan and the estimated costs and risks are presented.

  19. Recent Advances in Solar Cell Technology

    NASA Technical Reports Server (NTRS)

    Landis, Geoffrey A.; Bailey, Sheila G.; Piszczor, Michael F., Jr.

    1996-01-01

    The advances in solar cell efficiency, radiation tolerance, and cost over the last decade are reviewed. Potential performance of thin-film solar cells in space are discussed, and the cost and the historical trends in production capability of the photovoltaics industry are considered with respect to the requirements of space power systems. Concentrator cells with conversion efficiency over 30%, and nonconcentrating solar cells with efficiency over 25% are now available, and advanced radiation-tolerant cells and lightweight, thin-film arrays are both being developed. Nonsolar applications of solar cells, including thermophotovoltaics, alpha- and betavoltaics, and laser power receivers, are also discussed.

  20. SMEX-Lite Modular Solar Array Architecture

    NASA Technical Reports Server (NTRS)

    Lyons, John W.; Day, John (Technical Monitor)

    2002-01-01

    The NASA Small Explorer (SMEX) missions have typically had three years between mission definition and launch. This short schedule has posed significant challenges with respect to solar array design and procurement. Typically, the solar panel geometry is frozen prior to going out with a procurement. However, with the SMEX schedule, it has been virtually impossible to freeze the geometry in time to avoid scheduling problems with integrating the solar panels to the spacecraft. A modular solar array architecture was developed to alleviate this problem. This approach involves procuring sufficient modules for multiple missions and assembling the modules onto a solar array framework that is unique to each mission. The modular approach removes the solar array from the critical path of the SMEX integration and testing schedule. It also reduces the cost per unit area of the solar arrays and facilitates the inclusion of experiments involving new solar cell or panel technologies in the SMEX missions.

  1. Advanced solar dynamic technology program

    NASA Technical Reports Server (NTRS)

    Calogeras, James

    1990-01-01

    Viewgraphs and discussion on Advanced Solar Dynamic Technology Program are presented. Topics covered include: advanced solar dynamic technology program; advanced concentrators; advanced heat receivers; power conversion systems; dished all metal honeycomb sandwich panels; Stirling cavity heat pipe receiver; Brayton solar receiver; and thermal energy storage technology.

  2. Sentinel-3 Solar Array Design

    NASA Astrophysics Data System (ADS)

    Combet, Y.; Reutenauer, X.; Mouret, G.; Guerrere, S.; Ergan, A.; Ferrando, E.; Riva, S.; Hodgetts, P.; Levesque, D.; D'Accolti, G.

    2011-10-01

    Sentinel-3 is primarily a mission to support services relating to the marine environment, with capability to serve numerous land-, atmospheric- and cryospheric- based application areas. The mission's main objective is to determine parameters, such as sea-surface topography, sea- and land-surface temperatures, as well as ocean- and land-surface colours with high-end accuracy and reliability. For this mission, Thales Alenia Space has been selected as the spacecraft prime contractor and is also responsible for the solar array. In this frame, TAS leads a European industrial team, comprising Selex Galileo for the photovoltaic assembly and Patria for the panel substrate.

  3. Solar Cell and Array Technology Development for NASA Solar Electric Propulsion Missions

    NASA Technical Reports Server (NTRS)

    Piszczor, Michael; McNatt, Jeremiah; Mercer, Carolyn; Kerslake, Tom; Pappa, Richard

    2012-01-01

    NASA is currently developing advanced solar cell and solar array technologies to support future exploration activities. These advanced photovoltaic technology development efforts are needed to enable very large (multi-hundred kilowatt) power systems that must be compatible with solar electric propulsion (SEP) missions. The technology being developed must address a wide variety of requirements and cover the necessary advances in solar cell, blanket integration, and large solar array structures that are needed for this class of missions. Th is paper will summarize NASA's plans for high power SEP missions, initi al mission studies and power system requirements, plans for advanced photovoltaic technology development, and the status of specific cell and array technology development and testing that have already been conducted.

  4. Advanced planar array development for space station

    NASA Technical Reports Server (NTRS)

    1987-01-01

    The results of the Advanced Planar Array Development for the Space Station contract are presented. The original objectives of the contract were: (1) to develop a process for manufacturing superstrate assemblies, (2) to demonstrate superstrate technology through fabrication and test, (3) to develop and analyze a preliminary solar array wing design, and (4) to fabricate a wing segment based on wing design. The primary tasks completed were designing test modules, fabricating, and testing them. LMSC performed three tasks which included thermal cycle testing for 2000 thermal cycles, thermal balance testing at the Boeing Environmental Test Lab in Kent, Washington, and acceptance testing a 15 ft x 50 in panel segment for 100 thermal cycles. The surperstrate modules performed well during both thermal cycle testing and thermal balance testing. The successful completion of these tests demonstrate the technical feasibility of a solar array power system utilizing superstrate technology. This final report describes the major elements of this contract including the manufacturing process used to fabricate modules, the tests performed, and the results and conclusions of the tests.

  5. Evaluation of solar cells and arrays for potential solar power satellite applications

    NASA Technical Reports Server (NTRS)

    Almgren, D. W.; Csigi, K.; Gaudet, A. D.

    1978-01-01

    Proposed solar array designs and manufacturing methods are evaluated to identify options which show the greatest promise of leading up to the develpment of a cost-effective SPS solar cell array design. The key program elements which have to be accomplished as part of an SPS solar cell array development program are defined. The issues focussed on are: (1) definition of one or more designs of a candidate SPS solar array module, using results from current system studies; (2) development of the necessary manufacturing requirements for the candidate SPS solar cell arrays and an assessment of the market size, timing, and industry infrastructure needed to produce the arrays for the SPS program; (3) evaluation of current DOE, NASA and DOD photovoltaic programs to determine the impacts of recent advances in solar cell materials, array designs and manufacturing technology on the candidate SPS solar cell arrays; and (4) definition of key program elements for the development of the most promising solar cell arrays for the SPS program.

  6. Advanced Solar Power Systems

    NASA Technical Reports Server (NTRS)

    Atkinson, J. H.; Hobgood, J. M.

    1984-01-01

    The Advanced Solar Power System (ASPS) concentrator uses a technically sophisticated design and extensive tooling to produce very efficient (80 to 90%) and versatile energy supply equipment which is inexpensive to manufacture and requires little maintenance. The advanced optical design has two 10th order, generalized aspheric surfaces in a Cassegrainian configuration which gives outstanding performance and is relatively insensitive to temperature changes and wind loading. Manufacturing tolerances also have been achieved. The key to the ASPS is the direct absorption of concentrated sunlight in the working fluid by radiative transfers in a black body cavity. The basic ASPS design concepts, efficiency, optical system, and tracking and focusing controls are described.

  7. Heat-rejection design for large concentrating solar arrays

    NASA Technical Reports Server (NTRS)

    French, E. P.

    1980-01-01

    This paper considers the effect of heat rejection devices (radiators) on the performance and cost of large concentrating solar arrays for space application. Overall array characteristics are derived from the weight, cost, and performance of four major components; namely primary structure, optics/secondary structure, radiator, and solar panel. An ideal concentrator analysis is used to establish general cost and performance trends independent of specific array design. Both passive and heat-pipe radiation are evaluated, with an incremental cost-of-power approach used in the evaluation. Passive radiators are found to be more cost effective with silicon than with gallium arsenide (GaAs) arrays. Representative concentrating arrays have been evaluated for both near-term and advanced solar cell technology. Minimum cost of power is achieved at geometric concentration ratios in the range 2 to 6.

  8. Evaluation of space station solar array technology

    NASA Technical Reports Server (NTRS)

    1972-01-01

    The research concerning lightweight solar array assemblies since 1970 is reported. A bibliography of abstracts of documents used for reference during this period is included along with an evaluation of available solar array technology. A list of recommended technology programs is presented.

  9. Evaluation of materials for high performance solar arrays

    NASA Technical Reports Server (NTRS)

    Whitaker, A. F.; Smith, C. F., Jr.; Peacock, C. L., Jr.; Little, S. A.

    1978-01-01

    A program has been underway to evaluate materials for advanced solar arrays which are required to provide power to weight ratios up to 100 W/kg. Severe mission environments together with the lack of knowledge of space environmental materials degradation rates require the generation of irradiation and outgassing engineering data for use in the initial design phase of the flight solar arrays. Therefore, approximately 25 candidate array materials were subjected to selected mission environments of vacuum, UV, and particle irradiation, and their mechanical and/or optical properties were determined where appropriate.

  10. High-power, ultralow-mass solar arrays: FY-77 solar arrays technology readiness assessment report, volume 2

    NASA Technical Reports Server (NTRS)

    Costogue, E. N.; Young, L. E.; Brandhorst, H. W., Jr.

    1978-01-01

    Development efforts are reported in detail for: (1) a lightweight solar array system for solar electric propulsion; (2) a high efficiency thin silicon solar cell; (3) conceptual design of 200 W/kg solar arrays; (4) fluorocarbon encapsulation for silicon solar cell array; and (5) technology assessment of concentrator solar arrays.

  11. Solar array strip and a method for forming the same

    NASA Technical Reports Server (NTRS)

    Mueller, R. L.; Yasui, R. K. (Inventor)

    1979-01-01

    A flexible solar array strip is formed by providing printed circuitry between flexible layers of a nonconductive material, depositing solder pads on the printed circuitry, and storing the resulting substrate on a drum from which it is then withdrawn and advanced along a linear path. Solderless solar cells are serially transported into engagement with the pads and are infrared radiation to melt the solder and attach the cells to the circuitry. Excess flux is cleaned from the solar cells which are then encapsulated in a protective coating. The resulting array is then wound on a drum.

  12. A simplified solar cell array modelling program

    NASA Technical Reports Server (NTRS)

    Hughes, R. D.

    1982-01-01

    As part of the energy conversion/self sufficiency efforts of DSN engineering, it was necessary to have a simplified computer model of a solar photovoltaic (PV) system. This article describes the analysis and simplifications employed in the development of a PV cell array computer model. The analysis of the incident solar radiation, steady state cell temperature and the current-voltage characteristics of a cell array are discussed. A sample cell array was modelled and the results are presented.

  13. SEPS solar array design and technology evaluation

    NASA Technical Reports Server (NTRS)

    Elms, R. V., Jr.; Young, L. E.

    1975-01-01

    The technology developments required and a preliminary design of a lightweight 25 kW solar array for the solar electric propulsion stage (SEPS) have been defined. The requirements for a 65 W/Kg SEPS solar array system requires significant component weight reductions over present state-of-the-art flexible solar arrays in both electrical and structural-mechanical designs. A requirement for operation from 0.3 au to 6.0 au presents a wide range of temperature environments as well as severe combined thermal/vacuum/UV radiation environments. Additional requirements are capability for partial array retraction operation, and capability for full retraction and automatic preloading for survival of the Shuttle reentry environment. An assessment of current lightweight flexible solar array technology is made against the SEPS solar array requirements and new technology requirements are defined. A preliminary design and the operating characteristics of a flat-fold solar array system meeting the SEPS requirements is presented. A full-width, 10-ft-tall functional array model, including representative welded electrical modules and a model astromast, was fabricated and tested.

  14. Comparative values of advanced space solar cells

    NASA Technical Reports Server (NTRS)

    Slifer, L. W., Jr.

    1982-01-01

    A methodology for deriving a first order dollar value estimate for advanced solar cells which consists of defining scenarios for solar array production and launch to orbit and the associated costs for typical spacecraft, determining that portion affected by cell design and performance and determining the attributable cost differences is presented. Break even values are calculated for a variety of cells; confirming that efficiency and related effects of radiation resistance and temperature coefficient are major factors; array tare mass, packaging and packing factor are important; but cell mass is of lesser significance. Associated dollar values provide a means of comparison.

  15. Solar-cell array design handbook

    NASA Technical Reports Server (NTRS)

    Rauschenbach, H. S.

    1977-01-01

    Twelve-chapter two-volume compilation of solar cell design data is written from industrial, university, and governmental sources. Volumes contain tutorial descriptions of analytical methods, solar-cell characteristics, and cell material properties widely used in specifying solar-cell array performance and hardware design, as well as analysis, fabrication, and test methods.

  16. Rapid thermal cycling of new technology solar array blanket coupons

    NASA Technical Reports Server (NTRS)

    Scheiman, David A.; Smith, Bryan K.; Kurland, Richard M.; Mesch, Hans G.

    1990-01-01

    NASA Lewis Research Center is conducting thermal cycle testing of a new solar array blanket technologies. These technologies include test coupons for Space Station Freedom (SSF) and the advanced photovoltaic solar array (APSA). The objective of this testing is to demonstrate the durability or operational lifetime of the solar array interconnect design and blanket technology within a low earth orbit (LEO) or geosynchronous earth orbit (GEO) thermal cycling environment. Both the SSF and the APSA array survived all rapid thermal cycling with little or no degradation in peak performance. This testing includes an equivalent of 15 years in LEO for SSF test coupons and 30 years of GEO plus ten years of LEO for the APSA test coupon. It is concluded that both the parallel gap welding of the SSF interconnects and the soldering of the APSA interconnects are adequately designed to handle the thermal stresses of space environment temperature extremes.

  17. Solar Array Arcing Failure Mode and High Voltage Array Testing

    NASA Astrophysics Data System (ADS)

    Ferguson, Dale C.

    2002-10-01

    In 1998, a new failure mode for space solar arrays was discovered. A flowchart for this failure mode is presented. Since the discovery of this arc failure mode, many tactics have been used to defeat it. The arc thresholds and arc mitigation strategies must be determined in vacuum-plasma tank testing on Earth. Results from these tests must then be extrapolated to the space plasma environment. Thus, the test conditions on Earth must be adequate to reproduce the important aspects of the phenomenon in space. At Glenn Research Center, we have been testing solar arrays for their arc thresholds and sustained arcing thresholds. In this paper, we detail the test conditions for a specific set of tests-those aimed at qualifying the Boeing Solar Tile solar arrays to operate in space at very high voltages (300 V or more).

  18. Cassegrainian concentrator solar array exploratory development module

    SciTech Connect

    Patterson, R.E.; Crabtree, W.L.

    1982-08-01

    A multiyear program is underway for the development of a miniaturized Cassegrainian concentrator solar array concept which promises to significantly reduce the recurring costs of multikilowatt spacecraft solar arrays. The concentrator panels are comparable in thickness, area, and specific performance to conventional rigid solar array panels. Miniaturization of the concentrator element results in excellent heat distribution with passive thermal control for achievement of acceptably low steady state solar cell temperatures. A single element and a nine element demonstration module were designed, assembled, and tested. The test hardware has an effective concentration ratio of 88. Preliminary thermal vacuum test results indicate that the steady state solar cell temperature will be in the range of 75/sup 0/ to 95/sup 0/C with an effective concentration ratio of 100. Demonstration hardware test results obtained to date support the technical feasibility of the concept.

  19. Space Station Freedom Solar Array design development

    NASA Technical Reports Server (NTRS)

    Winslow, Cindy; Bilger, Kevin; Baraona, Cosmo R.

    1989-01-01

    The Space Station Freedom Solar Array Program is required to provide a 75 kW power module that uses eight solar array (SA) wings over a four-year period in low Earth orbit (LEO). Each wing will be capable of providing 23.4 kW at the 4-year design point. Lockheed Missles and Space Company, Inc. (LMSC) is providing the flexible substrate SAs that must survive exposure to the space environment, including atomic oxygen, for an operating life of fifteen years. Trade studies and development testing, important for evolving any design to maturity, are presently underway at LMSC on the flexible solar array. The trade study and development areas being investigated include solar cell module size, solar cell weld pads, panel stiffener frames, materials inherently resistant to atomic oxygen, and weight reduction design alternatives.

  20. Mars Array Technology Experiment Developed to Test Solar Arrays on Mars

    NASA Technical Reports Server (NTRS)

    Landis, Geoffrey A.

    2001-01-01

    Solar arrays will be the power supply for future missions to the planet Mars, including landers, rovers, and eventually human missions to explore the Martian surface. Until Mars Pathfinder landed in July 1997, no solar array had been used on the surface. The MATE package is intended to measure the solar energy reaching the surface, characterize the Martian environment to gather the baseline information required for designing power systems for long-duration missions, and to quantify the performance and degradation of advanced solar cells on the Martian surface. To measure the properties of sunlight reaching the Martian surface, MATE incorporates two radiometers and a visible/NIR spectrometer. The radiometers consist of multiple thermocouple junctions using thin-film technology. These devices generate a voltage proportional to the solar intensity. One radiometer measures the global broadband solar intensity, including both the direct and scattered sunlight, with a field of view of approximately 130. The second radiometer incorporates a slit to measure the direct (unscattered) intensity radiation. The direct radiometer can only be read once per day, with the Sun passing over the slit. The spectrometer measures the global solar spectrum with two 256-element photodiode arrays, one Si sensitive in the visible range (300 to 1100 nm), and a second InGaAs sensitive to the near infrared (900 to 1700 nm). This range covers 86 percent of the total energy from the Sun, with approximately 5-nm resolution. Each photodiode array has its own fiber-optic feed and grating. Although the purpose of the MATE is to gather data useful in designing solar arrays for Mars surface power systems, the radiometer and spectrometer measurements are expected to also provide important scientific data for characterizing the properties of suspended atmospheric dust. In addition to measuring the solar environment of Mars, MATE will measure the performance of five different individual solar cell types

  1. Parametric analysis of ATM solar array.

    NASA Technical Reports Server (NTRS)

    Singh, B. K.; Adkisson, W. B.

    1973-01-01

    The paper discusses the methods used for the calculation of ATM solar array performance characteristics and provides the parametric analysis of solar panels used in SKYLAB. To predict the solar array performance under conditions other than test conditions, a mathematical model has been developed. Four computer programs have been used to convert the solar simulator test data to the parametric curves. The first performs module summations, the second determines average solar cell characteristics which will cause a mathematical model to generate a curve matching the test data, the third is a polynomial fit program which determines the polynomial equations for the solar cell characteristics versus temperature, and the fourth program uses the polynomial coefficients generated by the polynomial curve fit program to generate the parametric data.

  2. Landsat 7 Solar Array Testing Experiences

    NASA Technical Reports Server (NTRS)

    Helfrich, Daniel

    2000-01-01

    This paper covers the extensive Landsat 7 solar array flight qualification testing effort. Details of the mechanical design of the solar array and its retention/release system are presented. A testing chronology is provided beginning with the onset of problems encountered at the subsystem level and carrying through the third and final powered-spacecraft ground deployment test. Design fixes and other changes are explained in the same order as they became necessary to flight-qualify the array. Some interesting lessons learned are included along with key references.

  3. Micrometeorite Impact Test of Flex Solar Array Coupon

    NASA Technical Reports Server (NTRS)

    Wright, K. H.; Schneider, T. A.; Vaughn, J. A.; Hoang, B.; Wong, F.; Gardiner, G.

    2016-01-01

    Spacecraft with solar arrays operate throughout the near earth environment and are planned for outer planet missions. An often overlooked test condition for solar arrays that is applicable to these missions is micrometeoroid impacts and possibly electrostatic discharge (ESD) events resulting from these impacts. NASA Marshall Space Flight Center (MSFC) is partnering with Space Systems/Loral, LLC (SSL) to examine the results of simulated micrometeoroid impacts on the electrical performance of an advanced, lightweight flexible solar array design. The test is performed at MSFC's Micro Light Gas Gun Facility with SSL-provided coupons. Multiple impacts were induced at various locations on a powered test coupon under different string voltage (0V-150V) and string current (1.1A - 1.65A) conditions. The setup, checkout, and results from the impact testing are discussed.

  4. Multi-kW solar arrays for Earth orbit applications

    NASA Technical Reports Server (NTRS)

    1985-01-01

    The multi-kW solar array program is concerned with developing the technology required to enable the design of solar arrays required to power the missions of the 1990's. The present effort required the design of a modular solar array panel consisting of superstrate modules interconnected to provide the structural support for the solar cells. The effort was divided into two tasks: (1) superstrate solar array panel design, and (2) superstrate solar array panel-to-panel design. The primary objective was to systematically investigate critical areas of the transparent superstrate solar array and evaluate the flight capabilities of this low cost approach.

  5. Solar Array Structures for 300 kW-Class Spacecraft

    NASA Technical Reports Server (NTRS)

    Pappa, Richard; Rose, Geoff; Mann, Troy O.; Warren, Jerry E.; Mikulas, Martin M., Jr.; Kerslake, Tom; Kraft, Tom; Banik, Jeremy

    2013-01-01

    State-of-the-art solar arrays for spacecraft provide on the order of 20 kW of electrical power, and they usually consist of 3J solar cells bonded to hinged rigid panels about 1 inch in thickness. This structural construction allows specific mass and packaging volumes of up to approximately 70 W/kg and 15 kW/m3 to be achieved. Significant advances in solar array structures are required for future very-high-power spacecraft (300+ kW), such as those proposed for pre-positioning heavy cargo on or near the Moon, Mars, or asteroids using solar electric propulsion. These applications will require considerable increases in both W/kg and kW/m3, and will undoubtedly require the use of flexible-substrate designs. This presentation summarizes work sponsored by NASA's Game Changing Development Program since Oct. 2011 to address the challenge of developing 300+ kW solar arrays. The work is primarily being done at NASA Langley, NASA Glenn, and two contractor teams (ATK and DSS), with technical collaboration from AFRL/Kirtland. The near-tem objective of the project is design, analysis, and testing of 30-50 kW solar array designs that are extensible to the far-term objective of 300+ kW. The work is currently focused on three designs: the MegaFlex concept by ATK, the Mega-ROSA concept by DSS, and an in-house 300-kW Government Reference Array concept. Each of these designs will be described in the presentation. Results obtained to date by the team, as well as future work plans, for the design, analysis, and testing of these large solar array structures will be summarized.

  6. Development of an Ultraflex-Based Thin Film Solar Array for Space Applications

    NASA Technical Reports Server (NTRS)

    White, Steve; Douglas, Mark; Spence, Brian; Jones, P. Alan; Piszczor, Michael F.

    2003-01-01

    As flexible thin film photovoltaic (FTFPV) cell technology is developed for space applications, integration into a viable solar array structure that optimizes the attributes of this cell technology is critical. An advanced version of ABLE'sS UltraFlex solar array platform represents a near-term, low-risk approach to demonstrating outstanding array performance with the implementation of FTFPV technology. Recent studies indicate that an advanced UltraFlex solar array populated with 15% efficient thin film cells can achieve over 200 W/kg EOL. An overview on the status of hardware development and the future potential of this technology is presented.

  7. Improved multispectral solar cell array

    NASA Technical Reports Server (NTRS)

    Redmann, J. J.

    1980-01-01

    Solar-collector system projects oval-shaped color-band images onto solar cells designed to be most efficient at specific wavelength. Image size can be altered by changing width of reflecting mirror of power of lens. Image intensity is thus kept at optimum level, preventing cells from overheating.

  8. Advanced Solar Cells for Satellite Power Systems

    NASA Technical Reports Server (NTRS)

    Flood, Dennis J.; Weinberg, Irving

    1994-01-01

    The multiple natures of today's space missions with regard to operational lifetime, orbital environment, cost and size of spacecraft, to name just a few, present such a broad range of performance requirements to be met by the solar array that no single design can suffice to meet them all. The result is a demand for development of specialized solar cell types that help to optimize overall satellite performance within a specified cost range for any given space mission. Historically, space solar array performance has been optimized for a given mission by tailoring the features of silicon solar cells to account for the orbital environment and average operating conditions expected during the mission. It has become necessary to turn to entirely new photovoltaic materials and device designs to meet the requirements of future missions, both in the near and far term. This paper will outline some of the mission drivers and resulting performance requirements that must be met by advanced solar cells, and provide an overview of some of the advanced cell technologies under development to meet them. The discussion will include high efficiency, radiation hard single junction cells; monolithic and mechanically stacked multiple bandgap cells; and thin film cells.

  9. Concentrator enhanced solar arrays design study

    NASA Technical Reports Server (NTRS)

    Lott, D. R.

    1978-01-01

    The analysis and preliminary design of a 25 kW concentrator enhanced lightweight flexible solar array are presented. The study was organized into five major tasks: (1) assessment and specification of design requirements; (2) mechanical design; (3) electric design; (4) concentrator design; and (5) cost projection. The tasks were conducted in an iterative manner so as to best derive a baseline design selection. The objectives of the study are discussed and comparative configurations and mass data on the SEP (Solar Electric Propulsion) array design, concentrator design options and configuration/mass data on the selected concentrator enhanced solar array baseline design are presented. Design requirements supporting design analysis and detailed baseline design data are discussed. The results of the cost projection analysis and new technology are also discussed.

  10. Large area flexible solar array design for Space Shuttle application

    NASA Technical Reports Server (NTRS)

    Souza, C. J.

    1980-01-01

    A large area flexible solar array has been designed for Shuttle power augmentation. The solar array utilizes large area, low cost, weldable solar cells. The paper addresses how the unique requirements of this system are implemented into the design. Economic and reliability issues relating to the optimization of a large area, foldable solar array concomitant to the Shuttle/Orbiter system are reviewed.

  11. Low cost silicon solar arrays

    NASA Technical Reports Server (NTRS)

    Ravi, K. V.; Serreze, H. B.; Bates, H. E.; Morrison, A. D.; Jewett, D. N.; Ho, J. C. T.; Schwuttke, G. H.; Ciszek, T. F.; Kran, A.

    1975-01-01

    Continuous growth methodology for silicon solar cell ribbons deals with capillary effects, die effects, thermal effects and crystal shape effects. Emphasis centers on the shape of the meniscus at the ribbon edge as a factor contributing to ribbon quality with respect to defect densities. Structural and electrical characteristics of edge defined, film-fed grown silicon ribbons are elaborated. Ribbon crystal solar cells produce AMO efficiencies of 6 to 10%.

  12. GPM Solar Array Gravity Negated Deployment Testing

    NASA Technical Reports Server (NTRS)

    Penn, Jonathan; Johnson, Chris; Lewis, Jesse; Dear, Trevin; Stewart, Alphonso

    2014-01-01

    NASA Goddard Space Flight Center (GSFC) successfully developed a g-negation support system for use on the solar arrays of the Global Precipitation Measurement (GPM) Satellite. This system provides full deployment capability at the subsystem and observatory levels. In addition, the system provides capability for deployed configuration first mode frequency verification testing. The system consists of air pads, a support structure, an air supply, and support tables. The g-negation support system was used to support all deployment activities for flight solar array deployment testing.

  13. Solar array experiments on the Sphinx satellite

    NASA Technical Reports Server (NTRS)

    Stevens, N. J.

    1973-01-01

    The Space Plasma, High Voltage Interaction Experiment (SPHINX) is the name given to an auxiliary payload satellite scheduled to be launched in January 1974. The principal experiments carried on this satellite are specifically designed to obtain the engineering data on the interaction of high voltage systems with the space plasma. The classes of experiments are solar array segments, insulators, insulators with pin holes and conductors. The satellite is also carrying experiments to obtain flight data on three new solar array configurations; the edge illuminated-multijunction cells, the Teflon encased cells and the violet cells.

  14. Cassegrainian concentrator solar array exploratory development module

    NASA Technical Reports Server (NTRS)

    Patterson, R. E.; Crabtree, W. L.

    1982-01-01

    A miniaturized Cassegrainian concentrator solar array concept is under development to reduce the cost of multi-kW spacecraft solar arrays. A primary parabolic reflector directs incoming solar energy to a secondary, centrally mounted inverted hyperbolic reflector and down onto a solar cell mounted on an Mo heat spreader on a 0.25 mm thick Al heat fin. Each unit is 12.7 mm thick, which makes the concentrator assembly roughly as thick as a conventional panel. The output is 100 W/sq and 20 W/kg, considering 20% efficient Si cells at 100 suns. A tertiary light catcher is mounted around the cell to ameliorate optic errors. The primary reflector is electroformed Ni with protective and reflective coatings. The cells have back surface reflectors and a SiO antireflective coating. An optical efficiency of 80% is projected, and GaAs cells are being considered in an attempt to raise cell efficiencies to over 30%.

  15. Integral glass encapsulation for solar arrays

    NASA Technical Reports Server (NTRS)

    Young, P. R.

    1977-01-01

    Electrostatic bonding has been used to join silicon solar cells to borosilicate glass without the aid of any organic binders or adhesives. The results of this investigation have been to demonstrate, without question, the feasibility of this process as an encapsulation technique. The potential of ESB for terrestrial solar arrays was clearly shown. The process is fast, reproducible, and produces a permanent bond between glass and silicon that is stronger than the silicon itself. Since this process is a glass sealing technique requiring no organics it makes moisture tight sealing of solar cells possible.

  16. Low-cost Solar Array (LSA) project

    NASA Technical Reports Server (NTRS)

    1978-01-01

    Progress made by the Low-Cost Silicon Solar Array Project during the period January through March 1978 is reported. It includes task reports on silicon material processing, large-area silicon sheet development, encapsulation materials testing and development, project engineering and operations, and manufacturing techniques, plus the steps taken to integrate these efforts.

  17. Heat Lamps Solder Solar Array Quickly

    NASA Technical Reports Server (NTRS)

    Coyle, P. J.; Crouthamel, M. S.

    1982-01-01

    Interconnection tabs in a nine-solar-cell array have been soldered simultaneously with radiant heat. Cells and tabs are held in position for soldering by sandwiching them between compliant silicone-rubber vacuum platen and transparent polyimide sealing membrane. Heat lamps warm cells, producing smooth, flat solder joints of high quality.

  18. Low cost silicon solar cell array

    NASA Technical Reports Server (NTRS)

    Bartels, F. T. C.

    1974-01-01

    The technological options available for producing low cost silicon solar cell arrays were examined. A project value of approximately $250/sq m and $2/watt is projected, based on mass production capacity demand. Recommendations are included for the most promising cost reduction options.

  19. The impact of solar cell technology on planar solar array performance

    NASA Technical Reports Server (NTRS)

    Mills, Michael W.; Kurland, Richard M.

    1989-01-01

    The results of a study into the potential impact of advanced solar cell technologies on the characteristics (weight, cost, area) of typical planar solar arrays designed for low, medium and geosynchronous altitude earth orbits are discussed. The study considered planar solar array substrate designs of lightweight, rigid-panel graphite epoxy and ultra-lightweight Kapton. The study proposed to answer the following questions: Do improved cell characteristics translate into array-level weight, size and cost improvements; What is the relative importance of cell efficiency, weight and cost with respect to array-level performance; How does mission orbital environment affect array-level performance. Comparisons were made at the array level including all mechanisms, hinges, booms, and harnesses. Array designs were sized to provide 5kW of array power (not spacecraft bus power, which is system dependent but can be scaled from given values). The study used important grass roots issues such as use of the GaAs radiation damage coefficients as determined by Anspaugh. Detailed costing was prepared, including cell and cover costs, and manufacturing attrition rates for the various cell types.

  20. (abstract) Scaling Nominal Solar Cell Impedances for Array Design

    NASA Technical Reports Server (NTRS)

    Mueller, Robert L; Wallace, Matthew T.; Iles, Peter

    1994-01-01

    This paper discusses a task the objective of which is to characterize solar cell array AC impedance and develop scaling rules for impedance characterization of large arrays by testing single solar cells and small arrays. This effort is aimed at formulating a methodology for estimating the AC impedance of the Mars Pathfinder (MPF) cruise and lander solar arrays based upon testing single cells and small solar cell arrays and to create a basis for design of a single shunt limiter for MPF power control of flight solar arrays having very different inpedances.

  1. Si Wire-Array Solar Cells

    NASA Astrophysics Data System (ADS)

    Boettcher, Shannon

    2010-03-01

    Micron-scale Si wire arrays are three-dimensional photovoltaic absorbers that enable orthogonalization of light absorption and carrier collection and hence allow for the utilization of relatively impure Si in efficient solar cell designs. The wire arrays are grown by a vapor-liquid-solid-catalyzed process on a crystalline (111) Si wafer lithographically patterned with an array of metal catalyst particles. Following growth, such arrays can be embedded in polymethyldisiloxane (PDMS) and then peeled from the template growth substrate. The result is an unusual photovoltaic material: a flexible, bendable, wafer-thickness crystalline Si absorber. In this paper I will describe: 1. the growth of high-quality Si wires with controllable doping and the evaluation of their photovoltaic energy-conversion performance using a test electrolyte that forms a rectifying conformal semiconductor-liquid contact 2. the observation of enhanced absorption in wire arrays exceeding the conventional light trapping limits for planar Si cells of equivalent material thickness and 3. single-wire and large-area solid-state Si wire-array solar cell results obtained to date with directions for future cell designs based on optical and device physics. In collaboration with Michael Kelzenberg, Morgan Putnam, Joshua Spurgeon, Daniel Turner-Evans, Emily Warren, Nathan Lewis, and Harry Atwater, California Institute of Technology.

  2. Low cost solar cell arrays

    NASA Technical Reports Server (NTRS)

    Iles, P. A.; Mclennan, H.

    1975-01-01

    Limitations in both space and terrestial markets for solar cells are described. Based on knowledge of the state-of-the-art, six cell options are discussed; as a result of this discussion, the three most promising options (involving high, medium and low efficiency cells respectively) were selected and analyzed for their probable costs. The results showed that all three cell options gave promise of costs below $10 per watt in the near future. Before further cost reductions can be achieved, more R and D work is required; suggestions for suitable programs are given.

  3. By-Pass Diode Temperature Tests of a Solar Array Coupon under Space Thermal Environment Conditions

    NASA Technical Reports Server (NTRS)

    Wright, Kenneth H.; Schneider, Todd A.; Vaughn, Jason A.; Hoang, Bao; Wong, Frankie; Wu, Gordon

    2016-01-01

    By-Pass diodes are a key design feature of solar arrays and system design must be robust against local heating, especially with implementation of larger solar cells. By-Pass diode testing was performed to aid thermal model development for use in future array designs that utilize larger cell sizes that result in higher string currents. Testing was performed on a 56-cell Advanced Triple Junction solar array coupon provided by SSL. Test conditions were vacuum with cold array backside using discrete by-pass diode current steps of 0.25 A ranging from 0 A to 2.0 A.

  4. Gallium arsenide solar array subsystem study

    NASA Technical Reports Server (NTRS)

    Miller, F. Q.

    1982-01-01

    The effects on life cycle costs of a number of technology areas are examined for a gallium arsenide space solar array. Four specific configurations were addressed: (1) a 250 KWe LEO mission - planer array; (2) a 250 KWe LEO mission - with concentration; (3) a 50 KWe GEO mission planer array; (4) a 50 KWe GEO mission - with concentration. For each configuration, a baseline system conceptual design was developed and the life cycle costs estimated in detail. The baseline system requirements and design technologies were then varied and their relationships to life cycle costs quantified. For example, the thermal characteristics of the baseline design are determined by the array materials and masses. The thermal characteristics in turn determine configuration, performance, and hence life cycle costs.

  5. Solar Array Verification Analysis Tool (SAVANT) Developed

    NASA Technical Reports Server (NTRS)

    Bailey, Sheila G.; Long, KIenwyn J.; Curtis, Henry B.; Gardner, Barbara; Davis, Victoria; Messenger, Scott; Walters, Robert

    1999-01-01

    Modeling solar cell performance for a specific radiation environment to obtain the end-of-life photovoltaic array performance has become both increasingly important and, with the rapid advent of new types of cell technology, more difficult. For large constellations of satellites, a few percent difference in the lifetime prediction can have an enormous economic impact. The tool described here automates the assessment of solar array on-orbit end-of-life performance and assists in the development and design of ground test protocols for different solar cell designs. Once established, these protocols can be used to calculate on-orbit end-of-life performance from ground test results. The Solar Array Verification Analysis Tool (SAVANT) utilizes the radiation environment from the Environment Work Bench (EWB) model developed by the NASA Lewis Research Center s Photovoltaic and Space Environmental Effects Branch in conjunction with Maxwell Technologies. It then modifies and combines this information with the displacement damage model proposed by Summers et al. (ref. 1) of the Naval Research Laboratory to determine solar cell performance during the course of a given mission. The resulting predictions can then be compared with flight data. The Environment WorkBench (ref. 2) uses the NASA AE8 (electron) and AP8 (proton) models of the radiation belts to calculate the trapped radiation flux. These fluxes are integrated over the defined spacecraft orbit for the duration of the mission to obtain the total omnidirectional fluence spectra. Components such as the solar cell coverglass, adhesive, and antireflective coatings can slow and attenuate the particle fluence reaching the solar cell. In SAVANT, a continuous slowing down approximation is used to model this effect.

  6. SEP solar array Shuttle flight experiment

    NASA Technical Reports Server (NTRS)

    Elms, R. V., Jr.; Young, L. E.; Hill, H. C.

    1981-01-01

    An experiment to verify the operational performance of a full-scale Solar Electric Propulsion (SEP) solar array is described. Scheduled to fly on the Shuttle in 1983, the array will be deployed from the bay for ten orbits, with dynamic excitation to test the structural integrity being furnished by the Orbiter verniers; thermal, electrical, and sun orientation characteristics will be monitored, in addition to safety, reliability, and cost effective performance. The blanket, with aluminum and glass as solar cell mass simulators, is 4 by 32 m, with panels (each 0.38 by 4 m) hinged together; two live Si cell panels will be included. The panels are bonded to stiffened graphite-epoxy ribs and are storable in a box in the bay. The wing support structure is detailed, noting the option of releasing the wing into space by use of the Remote Manipulator System if the wing cannot be refolded. Procedures and equipment for monitoring the array behavior are outlined, and comprise both analog data and TV recording for later playback and analysis. The array wing experiment will also aid in developing measurement techniques for large structure dynamics in space.

  7. Preface: Advances in solar physics

    NASA Astrophysics Data System (ADS)

    Georgoulis, Manolis K.; Nakariakov, Valery M.

    2015-12-01

    The idea for this special issue of Advances in Space Research (ASR) was formulated during the 14th European Solar Physics Meeting (ESPM-14) that took place in Dublin, Ireland in September 2014. Since ASR does not publish conference proceedings, it was decided to extend a general call to the international solar-physics community for manuscripts pertinent to the following thematic areas: New and upcoming heliospheric observational and data assimilation facilities.

  8. Method of fabricating a solar cell array

    DOEpatents

    Lazzery, Angelo G.; Crouthamel, Marvin S.; Coyle, Peter J.

    1982-01-01

    A first set of pre-tabbed solar cells are assembled in a predetermined array with at least part of each tab facing upward, each tab being fixed to a bonding pad on one cell and abutting a bonding pad on an adjacent cell. The cells are held in place with a first vacuum support. The array is then inverted onto a second vacuum support which holds the tabs firmly against the cell pads they abut. The cells are exposed to radiation to melt and reflow the solder pads for bonding the tab portions not already fixed to bonding pads to these pads.

  9. Advanced UV Detectors and Detector Arrays

    NASA Technical Reports Server (NTRS)

    Pankove, Jacques I.; Torvik, John

    1998-01-01

    Gallium Nitride (GaN) with its wide energy bandgap of 3.4 eV holds excellent promise for solar blind UV detectors. We have successfully designed, fabricated and tested GaN p-i-n detectors and detector arrays. The detectors have a peak responsivity of 0.14A/W at 363 nm (3.42 eV) at room temperature. This corresponds to an internal quantum efficiency of 56%. The responsivity decreases by several orders of magnitude to 0.008 A/W at 400 nm (3.10 eV) giving the excellent visible rejection ratio needed for solar-blind applications.

  10. Integral glass encapsulation for solar arrays

    NASA Technical Reports Server (NTRS)

    Landis, G. A.

    1981-01-01

    Electrostatic bonding technology, an encapsulation technique for terrestrial solar array was developed. The process produces full integral, hermetic bonds with no adhesives or pottants. Panels of six solar cells on a simple glass superstrate were produced. Electrostatic bonding for making the cell front contact was also developed. A metal mesh is trapped into contact with the cell front during the bonding process. Six cell panels using the bonded mesh as the only cell front contact were produced. The possibility of using lower cost glass, with a higher thermal expansion mismatch to silicon, by making lower temperature bonds is developed. However, this requires a planar surface cell.

  11. Solar panels offer array of hope.

    PubMed

    Baillie, Jonathan

    2009-01-01

    The installation of what is believed to be the largest array of solar thermal panels currently in use at a UK NHS hospital has taken place at an ideal time for the facility in question, Harlow's Princess Alexandra Hospital, with the hospital's gas bill alone having risen by 153% over the past nine months thanks to soaring energy prices, and the estates department keen to mitigate the effects in any way possible. Jonathan Baillie reports.

  12. Solar panels offer array of hope.

    PubMed

    Baillie, Jonathan

    2009-01-01

    The installation of what is believed to be the largest array of solar thermal panels currently in use at a UK NHS hospital has taken place at an ideal time for the facility in question, Harlow's Princess Alexandra Hospital, with the hospital's gas bill alone having risen by 153% over the past nine months thanks to soaring energy prices, and the estates department keen to mitigate the effects in any way possible. Jonathan Baillie reports. PMID:19192602

  13. Solar Array Module Plasma Interaction Experiment (SAMPIE)

    NASA Technical Reports Server (NTRS)

    Ferguson, Dale C.

    1992-01-01

    The objective of the Solar Array Module Plasma Interaction Experiment (SAMPIE) is to investigate, by means of a shuttle-based flight experiment and relevant ground-based testing, the arcing and current collection behavior of materials and geometries likely to be exposed to the LEO plasma on high-voltage space power systems, in order to minimize adverse environmental interactions. An overview of the SAMPIE program is presented in outline and graphical form.

  14. Impact of Solar Array Designs on High Voltage Operations

    NASA Technical Reports Server (NTRS)

    Brandhorst, Henry W., Jr.; Ferguson, Dale; Piszczor, Mike; ONeill, Mark

    2006-01-01

    As power levels of advanced spacecraft climb above 25 kW, higher solar array operating voltages become attractive. Even in today s satellites, operating spacecraft buses at 100 V and above has led to arcing in GEO communications satellites, so the issue of spacecraft charging and solar array arcing remains a design problem. In addition, micrometeoroid impacts on all of these arrays can also lead to arcing if the spacecraft is at an elevated potential. For example, tests on space station hardware disclosed arcing at 75V on anodized A1 structures that were struck with hypervelocity particles in Low Earth Orbit (LEO) plasmas. Thus an understanding of these effects is necessary to design reliable high voltage solar arrays of the future, especially in light of the Vision for Space Exploration of NASA. In the future, large GEO communication satellites, lunar bases, solar electric propulsion missions, high power communication systems around Mars can lead to power levels well above 100 kW. As noted above, it will be essential to increase operating voltages of the solar arrays well above 80 V to keep the mass of cabling needed to carry the high currents to an acceptable level. Thus, the purpose of this paper is to discuss various solar array approaches, to discuss the results of testing them at high voltages, in the presence of simulated space plasma and under hypervelocity impact. Three different types of arrays will be considered. One will be a planar array using thin film cells, the second will use planar single or multijunction cells and the last will use the Stretched Lens Array (SLA - 8-fold concentration). Each of these has different approaches for protection from the space environment. The thin film cell based arrays have minimal covering due to their inherent radiation tolerance, conventional GaAs and multijunction cells have the traditional cerium-doped microsheet glasses (of appropriate thickness) that are usually attached with Dow Corning DC 93-500 silicone

  15. Advanced ACTPol Cryogenic Detector Arrays and Readout

    NASA Astrophysics Data System (ADS)

    Henderson, S. W.; Allison, R.; Austermann, J.; Baildon, T.; Battaglia, N.; Beall, J. A.; Becker, D.; De Bernardis, F.; Bond, J. R.; Calabrese, E.; Choi, S. K.; Coughlin, K. P.; Crowley, K. T.; Datta, R.; Devlin, M. J.; Duff, S. M.; Dunkley, J.; Dünner, R.; van Engelen, A.; Gallardo, P. A.; Grace, E.; Hasselfield, M.; Hills, F.; Hilton, G. C.; Hincks, A. D.; Hloẑek, R.; Ho, S. P.; Hubmayr, J.; Huffenberger, K.; Hughes, J. P.; Irwin, K. D.; Koopman, B. J.; Kosowsky, A. B.; Li, D.; McMahon, J.; Munson, C.; Nati, F.; Newburgh, L.; Niemack, M. D.; Niraula, P.; Page, L. A.; Pappas, C. G.; Salatino, M.; Schillaci, A.; Schmitt, B. L.; Sehgal, N.; Sherwin, B. D.; Sievers, J. L.; Simon, S. M.; Spergel, D. N.; Staggs, S. T.; Stevens, J. R.; Thornton, R.; Van Lanen, J.; Vavagiakis, E. M.; Ward, J. T.; Wollack, E. J.

    2016-08-01

    Advanced ACTPol is a polarization-sensitive upgrade for the 6 m aperture Atacama Cosmology Telescope, adding new frequencies and increasing sensitivity over the previous ACTPol receiver. In 2016, Advanced ACTPol will begin to map approximately half the sky in five frequency bands (28-230 GHz). Its maps of primary and secondary cosmic microwave background anisotropies—imaged in intensity and polarization at few arcminute-scale resolution—will enable precision cosmological constraints and also a wide array of cross-correlation science that probes the expansion history of the universe and the growth of structure via gravitational collapse. To accomplish these scientific goals, the Advanced ACTPol receiver will be a significant upgrade to the ACTPol receiver, including four new multichroic arrays of cryogenic, feedhorn-coupled AlMn transition edge sensor polarimeters (fabricated on 150 mm diameter wafers); a system of continuously rotating meta-material silicon half-wave plates; and a new multiplexing readout architecture which uses superconducting quantum interference devices and time division to achieve a 64-row multiplexing factor. Here we present the status and scientific goals of the Advanced ACTPol instrument, emphasizing the design and implementation of the Advanced ACTPol cryogenic detector arrays.

  16. Advanced ACTPol Cryogenic Detector Arrays and Readout

    NASA Technical Reports Server (NTRS)

    Henderson, S.W.; Allison, R.; Austermann, J.; Baildon, T.; Battaglia, N.; Beall, J. A.; Becker, D.; De Bernardis, F.; Bond, J. R.; Wollack, E. J.

    2016-01-01

    Advanced ACTPol is a polarization-sensitive upgrade for the 6 m aperture Atacama Cosmology Telescope, adding new frequencies and increasing sensitivity over the previous ACTPol receiver. In 2016, Advanced ACTPol will begin to map approximately half the sky in five frequency bands (28-230 GHz). Its maps of primary and secondary cosmic microwave background anisotropies-imaged in intensity and polarization at few arcminute-scale resolution-will enable precision cosmological constraints and also awide array of cross-correlation science that probes the expansion history of the universe and the growth of structure via gravitational collapse. To accomplish these scientific goals, the AdvancedACTPol receiver will be a significant upgrade to the ACTPol receiver, including four new multichroic arrays of cryogenic, feedhorn-coupled AlMn transition edge sensor polarimeters (fabricated on 150 mm diameter wafers); a system of continuously rotating meta-material silicon half-wave plates; and a new multiplexing readout architecture which uses superconducting quantum interference devices and time division to achieve a 64-row multiplexing factor. Here we present the status and scientific goals of the Advanced ACTPol instrument, emphasizing the design and implementation of the AdvancedACTPol cryogenic detector arrays.

  17. Fault Analysis in Solar Photovoltaic Arrays

    NASA Astrophysics Data System (ADS)

    Zhao, Ye

    Fault analysis in solar photovoltaic (PV) arrays is a fundamental task to increase reliability, efficiency and safety in PV systems. Conventional fault protection methods usually add fuses or circuit breakers in series with PV components. But these protection devices are only able to clear faults and isolate faulty circuits if they carry a large fault current. However, this research shows that faults in PV arrays may not be cleared by fuses under some fault scenarios, due to the current-limiting nature and non-linear output characteristics of PV arrays. First, this thesis introduces new simulation and analytic models that are suitable for fault analysis in PV arrays. Based on the simulation environment, this thesis studies a variety of typical faults in PV arrays, such as ground faults, line-line faults, and mismatch faults. The effect of a maximum power point tracker on fault current is discussed and shown to, at times, prevent the fault current protection devices to trip. A small-scale experimental PV benchmark system has been developed in Northeastern University to further validate the simulation conclusions. Additionally, this thesis examines two types of unique faults found in a PV array that have not been studied in the literature. One is a fault that occurs under low irradiance condition. The other is a fault evolution in a PV array during night-to-day transition. Our simulation and experimental results show that overcurrent protection devices are unable to clear the fault under "low irradiance" and "night-to-day transition". However, the overcurrent protection devices may work properly when the same PV fault occurs in daylight. As a result, a fault under "low irradiance" and "night-to-day transition" might be hidden in the PV array and become a potential hazard for system efficiency and reliability.

  18. The solar array is installed on ACE in SAEF-2

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Applied Physics Laboratory engineers and technicians from Johns Hopkins University assist in guiding the Advanced Composition Explorer (ACE) as it is hoisted over a platform for solar array installation in KSC's Spacecraft Assembly and Encapsulation Facility-II. Scheduled for launch on a Delta II rocket from Cape Canaveral Air Station on Aug. 25, ACE will study low-energy particles of solar origin and high-energy galactic particles. The ACE observatory will contribute to the understanding of the formation and evolution of the solar system as well as the astrophysical processes involved. The collecting power of instruments aboard ACE is 10 to 1,000 times greater than anything previously flown to collect similar data by NASA.

  19. The solar array is installed on ACE in SAEF-2

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Applied Physics Laboratory Engineer Cliff Willey (kneeling) and Engineering Assistant Jim Hutcheson from Johns Hopkins University install solar array panels on the Advanced Composition Explorer (ACE) in KSC's Spacecraft Assembly and Encapsulation Facility-II. Scheduled for launch on a Delta II rocket from Cape Canaveral Air Station on Aug. 25, ACE will study low-energy particles of solar origin and high-energy galactic particles for a better understanding of the formation and evolution of the solar system as well as the astrophysical processes involved. The ACE observatory will be placed into an orbit almost a million miles (1.5 million kilometers) away from the Earth, about 1/100 the distance from the Earth to the Sun. The collecting power of instrumentation aboard ACE is at least 100 times more sensitive than anything previously flown to collect similar data by NASA.

  20. Series-parallel method of direct solar array regulation

    NASA Technical Reports Server (NTRS)

    Gooder, S. T.

    1976-01-01

    A 40 watt experimental solar array was directly regulated by shorting out appropriate combinations of series and parallel segments of a solar array. Regulation switches were employed to control the array at various set-point voltages between 25 and 40 volts. Regulation to within + or - 0.5 volt was obtained over a range of solar array temperatures and illumination levels as an active load was varied from open circuit to maximum available power. A fourfold reduction in regulation switch power dissipation was achieved with series-parallel regulation as compared to the usual series-only switching for direct solar array regulation.

  1. A second solar array is moved to the IEA

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Workers in the Space Station Processing Facility get ready to attach an overhead crane (center top) to the solar array below it to move the array for installation onto the Integrated Equipment Assembly (IEA). A component of the International Space Station, the solar array is the second one being installed on the IEA. The arrays are scheduled to be launched on mission STS-97 in late November along with the P6 truss. The Station's electrical power system (EPS) will use eight photovoltaic solar arrays to convert sunlight to electricity. Each of the eight solar arrays will be 112 feet long by 39 feet wide. The solar arrays are mounted on a '''blanket''' that can be folded like an accordion for delivery. Once in orbit, astronauts will deploy the blankets to their full size. Gimbals will be used to rotate the arrays so that they will face the Sun to provide maximum power to the Space Station.

  2. A second solar array is moved to the IEA

    NASA Technical Reports Server (NTRS)

    2000-01-01

    The overhead crane carrying a solar array turns on its axis to move the array to the Integrated Equipment Assembly (IEA) for installation. A component of the International Space Station, the solar array is the second one being installed on the IEA. The arrays are scheduled to be launched on mission STS-97 in late November along with the P6 truss. The Station's electrical power system (EPS) will use eight photovoltaic solar arrays to convert sunlight to electricity. Each of the eight solar arrays will be 112 feet long by 39 feet wide. The solar arrays are mounted on a '''blanket''' that can be folded like an accordion for delivery. Once in orbit, astronauts will deploy the blankets to their full size. Gimbals will be used to rotate the arrays so that they will face the Sun to provide maximum power to the Space Station.

  3. Modeling and reconfiguration of solar photovoltaic arrays under non-uniform shadow conditions

    NASA Astrophysics Data System (ADS)

    Nguyen, Dung Duc

    will focus on the development of an adaptable solar array that is able to optimize power output, reconfigure itself when solar cells are damaged and create controllable output voltages and currents. This study will be a technological advancement over the existing technology of solar PV. Presently solar arrays are fixed arrays that require external device to control their output. In this research, the solar array will be able to self-reconfigure, leading to the following advantages: (1) Higher efficiency because no external devices are used. (2) Can reach maximum possible output power that is much higher than the maximum power of fixed solar arrays by arranging the solar cells in optimized connections. (3) Elimination of the hot spot effects. The proposed research has the following goals: First, to create a modeling and computing algorithm, which is able to simulate and analyze the effects of non-uniform changing shadows on the output power of solar PV arrays. Our model will be able to determine the power losses in each solar cell and the collective hot spots of an array. Second, to propose new methods, which are able to predict the performance of solar PV arrays under shadow conditions for long term (days, months, years). Finally, to develop adaptive reconfiguration algorithms to reconfigure connections within solar PV arrays in real time, under shadow conditions, in order to optimize output power.

  4. Micrometeorite Impact Test of Flex Solar Array Coupon

    NASA Technical Reports Server (NTRS)

    Wright, K. H.; Schneider, T. A.; Vaughn, J. A.; Hoang, B.; Wong, F.; Gardiner, G.

    2016-01-01

    Spacecraft with solar arrays operate throughout the near earth environment and are increasingly planned for outer planet missions. An often overlooked test condition for solar arrays that is applicable to these missions is micrometeorite impacts and possibly electrostatic discharge (ESD) events resulting from these impacts. The Marshall Space Flight Center (MSFC) is partnering with Space Systems/Loral, LLC (SSL) to examine the results of simulated micrometeorite impacts on the electrical performance of an advanced, lightweight flexible solar array design. The test is performed at NASA MSFC's Microlight Gas Gun Facility. The SSL-provided coupons consist of three strings, each string with two solar cells in series. Five impacts will be induced at various locations on a powered test coupon under different string voltage (0 volts - 150 volts) and string current (1.1 amperes - 1.65 amperes) conditions. The maximum specified test voltage and current represent margins of 1.5 times for both voltage and current. The test parameters are chosen to demonstrate new array design robustness to any ESD event caused by plasma plumes resulting from a simulated micrometeorite impact. A second unpowered coupon will undergo two impacts: one impact on the front side and one impact on the back side. Following the impact testing, the second coupon will be exposed to a thermal cycle test to determine possible damage propagation and further electrical degradation due to thermally-induced stress. The setup, checkout, and results from the impact testing are discussed. The challenges for impact testing include precise coupon alignment to control impact location; pressure management during the impact process; and measurement of the true transient electrical response during impact on the powered coupon. Results from pre- and post-test visual and electrical functional testing are also discussed.

  5. Torsional Buckling Tests of a Simulated Solar Array

    NASA Technical Reports Server (NTRS)

    Thornton, E. A.

    1996-01-01

    Spacecraft solar arrays are typically large structures supported by long, thin deployable booms. As such, they may be particularly susceptible to abnormal structural behavior induced by mechanical and thermal loading. One example is the Hubble Space Telescope solar arrays which consist of two split tubes fit one inside the other called BiSTEMs. The original solar arrays on the Hubble Space Telescope were found to be severely twisted following deployment and later telemetry data showed the arrays were vibrating during daylight to night and night to daylight transition. The solar array twist however can force the BiSTEM booms to change in cross-section and cause tile solar arrays to react unpredictably to future loading. The solar arrays were redesigned to correct for tile vibration, however, upon redeployment they again twisted. To assess the influence of boom cross-sectional configuration, experiments were conducted on two types of booms, (1)booms with closed cross-sections, and (2) booms with open cross-sections. Both models were subjected to compressive loading and imposed tip deflections. An existing analytical model by Chung and Thornton was used to define the individual load ranges for each model solar array configuration. The load range for the model solar array using closed cross-section booms was 0-120 Newtons and 0-160 Newtons for the model solar array using open cross-section booms. The results indicate the model solar array with closed cross-section booms buckled only in flexure. However, the results of the experiment with open cross-section booms indicate the model solar array buckled only in torsion and with imposed tip deflections the cross section can degrade by rotation of the inner relative to the outer STEM. For tile Hubble Space Telescope solar arrays the results of these experiments indicate the twisting resulted from the initial mechanical loading of the open cross-section booms.

  6. Photovoltaic solar array technology required for three wide scale generating systems for terrestrial applications: rooftop, solar farm, and satellite

    NASA Technical Reports Server (NTRS)

    Berman, P. A.

    1972-01-01

    Three major options for wide-scale generation of photovoltaic energy for terrestrial use are considered: (1) rooftop array, (2) solar farm, and (3) satellite station. The rooftop array would use solar cell arrays on the roofs of residential or commercial buildings; the solar farm would consist of large ground-based arrays, probably in arid areas with high insolation; and the satellite station would consist of an orbiting solar array, many square kilometers in area. The technology advancement requirements necessary for each option are discussed, including cost reduction of solar cells and arrays, weight reduction, resistance to environmental factors, reliability, and fabrication capability, including the availability of raw materials. The majority of the technology advancement requirements are applicable to all three options, making possible a flexible basic approach regardless of the options that may eventually be chosen. No conclusions are drawn as to which option is most advantageous, since the feasibility of each option depends on the success achieved in the technology advancement requirements specified.

  7. Lightweight Reusable Solar Array For Balloons

    NASA Astrophysics Data System (ADS)

    Aaron, K.; Tensor, P.; Nock, K.; Wyszkowski, C.

    We will discuss a new lightweight reusable solar array system, dubbed HighPower, which is being developed for the Ultra-Long Duration Balloon (ULDB) program using NASA/SBIR funding, but which is also applicable to other balloon systems. The system uses a vertically deployed stack of panels suspended from their corners by cables. The stack act likes a two-dimensional Venetian blind. By raising and lowering opposite corners, the array of parallel panels can be pointed over most of the upper hemisphere. This allows the panels to remain normal to the sun despite the slow rotation of the gondola and without requiring rotation of the system (no slip rings) or heavy cantilevered rotation joints. The system is sized to generate 2000 W using six 2m x 2m panels. The modularity of the system allows panels to be added or removed to tailored the power to the needs of the mission. Prior to cut -down of the balloon, the panels can be retracted and stowed compactly in the lower part of the gondola. This will protect the array during landing, allowing the array to be reused on subsequent flights.

  8. SEPS solar array design and technology evaluation. [Solar Electric Propulsion Stage

    NASA Technical Reports Server (NTRS)

    Elms, R. V., Jr.; Young, L. E.

    1975-01-01

    The solar array system considered is composed of two wings. Each wing consists of a solar array blanket, a blanket launch storage container, an extension/retraction mast assembly, a blanket tensioning system, and an array electrical harness. A technology evaluation is performed to assess the applicable solar array state-of-the-art and to define the supporting effort necessary to achieve technology readiness for meeting the Solar Electric Propulsion Stage (SEPS) solar array design requirements. Details of mechanical design are discussed along with questions of electrical design, operational reliability advantages, and array assembly advantages.

  9. A second solar array is moved to the IEA

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Workers in the Space Station Processing Facility help guide an overhead crane toward a workstand containing a solar array in order to move it for installation onto the Integrated Equipment Assembly (IEA). A component of the International Space Station, the solar array is the second one being installed on the IEA. The arrays are scheduled to be launched on mission STS-97 in late November along with the P6 truss. The Station's electrical power system (EPS) will use eight photovoltaic solar arrays to convert sunlight to electricity. Each of the eight solar arrays will be 112 feet long by 39 feet wide. The solar arrays are mounted on a '''blanket''' that can be folded like an accordion for delivery. Once in orbit, astronauts will deploy the blankets to their full size. Gimbals will be used to rotate the arrays so that they will face the Sun to provide maximum power to the Space Station.

  10. A second solar array is moved to the IEA

    NASA Technical Reports Server (NTRS)

    2000-01-01

    In the Space Station Processing Facility, workers help guide a solar array into position for installation on the Integrated Equipment Assembly. Solar Array Wing-3 is already in place. Components of the International Space Station, the arrays are scheduled to be launched on mission STS-97 in late November along with the P6 truss. The Station's electrical power system (EPS) will use eight photovoltaic solar arrays to convert sunlight to electricity. Each of the eight solar arrays will be 112 feet long by 39 feet wide. The solar arrays are mounted on a '''blanket''' that can be folded like an accordion for delivery. Once in orbit, astronauts will deploy the blankets to their full size. Gimbals will be used to rotate the arrays so that they will face the Sun to provide maximum power to the Space Station.

  11. Space Station Solar Array Joint Repair

    NASA Technical Reports Server (NTRS)

    Loewenthal, Stuart; Allmon, Curtis; Reznik, Carter; McFatter, Justin; Davis, Robert E.

    2015-01-01

    In Oct 2007 the International Space Station (ISS) crew noticed a vibrating camera in the vicinity of Starboard Solar Alpha Rotary Joint (SARJ). It had less than 5 months of run time when the anomaly was observed. This approximately 3.2 meter diameter bearing joint supports solar arrays that power the station critical to its operation. The crew performed an EVA to identify what was causing the vibration. It was discovered that one of the 3 bearing tracks of this unconventional bearing had significant spalling damage. This paper discusses the SARJ's unique bearing design and the vulnerability in its design leading to the observed anomaly. The design of a SARJ vacuum test rig is also described along with the results of a life test that validated the proposed repair should extend the life of the SARJ a minimum of 18 years on-orbit.

  12. Design and development of a solar array drive. [a direct drive solar array pointing mechanism

    NASA Technical Reports Server (NTRS)

    Rees, T.; Standing, J. M.

    1977-01-01

    The design and development of a dry lubricated direct drive solar array pointing mechanism is discussed for use on the Orbital Test Satellite (OTS), MAROTS, European Communication Satellite (ECS), and others. Results of life testing the original prototype and the OTS mechanism are presented together with an appraisal of expected future development.

  13. Low-cost silicon solar array project environmental hail model for assessing risk to solar collectors

    NASA Technical Reports Server (NTRS)

    Gonzalez, C.

    1977-01-01

    The probability of solar arrays being struck by hailstones of various sizes as a function of geographic location and service life was assessed. The study complements parallel studies of solar array sensitivity to hail damage, the final objective being an estimate of the most cost effective level for solar array hail protection.

  14. Test report SEPS solar array root section model

    NASA Technical Reports Server (NTRS)

    1974-01-01

    The fabrication and test of a solar array functional root section model to verify preliminary array design concepts is presented. The root section model is full scale width and contains a model array blanket. The blanket contains 1/8 live electrical modules and the remainder contains solar cell mass simulators. A storable Astromast is used for array blanket extension and retraction. The model component and system assembly hardware, tests, and test results are described.

  15. GEO Satellite Solar Array Abnormality's Analysis and Treatment

    NASA Astrophysics Data System (ADS)

    Wang, Junyan; Yang, Yujie; Zhu, Weibo; Liu, Jingyong; Xu, Hui

    Solar array, converting sunlight into electricity, is one of the most important components in satellite energy subsystem. It is significant for in-orbit satellite safety that solar array and its subsidiaries work normally. An abnormal phenomenon that the output current of one solar array suddenly decreased happened in a GEO satellite. Combined with the structure of the solar array system and the trends of relevant parameters during the abnormality, the paper analyzed the possible reasons, and detected the root cause, and finally provided an emergency treatment for this kind of abnormality.

  16. Solar array technology evaluation program for SEPS (Solar Electrical Propulsion Stage)

    NASA Technical Reports Server (NTRS)

    1974-01-01

    An evaluation of the technology and the development of a preliminary design for a 25 kilowatt solar array system for solar electric propulsion are discussed. The solar array has a power to weight ratio of 65 watts per kilogram. The solar array system is composed of two wings. Each wing consists of a solar array blanket, a blanket launch storage container, an extension/retraction mast assembly, a blanket tensioning system, an array electrical harness, and hardware for supporting the system for launch and in the operating position. The technology evaluation was performed to assess the applicable solar array state-of-the-art and to define supporting research necessary to achieve technology readiness for meeting the solar electric propulsion system solar array design requirements.

  17. Solar magnetograph employing integrated diode arrays.

    PubMed

    Livingston, W C; Harvey, J; Slaughter, C; Trumbo, D

    1976-01-01

    A solar magnetograph employing as detectors a pair of self-scanning 512-element integrated diode arrays is described. Coupled to a 1.5-m telescope, photospheric flux as small as 5(10(16)) maxwells is detected, corresponding in intensity to DeltaI/I = 3(10(-4)) at lambda 0.8688 microm. Measured photometric properties of the diode array are given, including MTF as a function of wavelength, dark current as a function of temperature, completeness of readout, optical and electronic fixed-pattern noise. An integrating preamplifier is presented that achieves a measured noise, when connected to the array, equivalent to 950 electrons at the input for a bandwidth of 3(10(5)) Hz. These data provide a basis for an evaluation of the detector performance at low light levels beyond the needs of the magnetograph. Operated at near liquid nitrogen temperature, the noise and cooling characteristics indicate the detector has promise as a low light level sensor.

  18. A second solar array is moved to the IEA

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Workers in the Space Station Processing Facility prepare an overhead crane they will use to move a solar array, a component of the International Space Station, for installation onto the Integrated Equipment Assembly. The solar array is the second one being installed. They are scheduled to be launched on mission STS-97 in late November along with the P6 truss. The Station's electrical power system (EPS) will use eight photovoltaic solar arrays to convert sunlight to electricity. Each of the eight solar arrays will be 112 feet long by 39 feet wide. The solar arrays are mounted on a '''blanket''' that can be folded like an accordion for delivery. Once in orbit, astronauts will deploy the blankets to their full size. Gimbals will be used to rotate the arrays so that they will face the Sun to provide maximum power to the Space Station.

  19. A solar array is moved in the SSPF for testing

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Workers in the Space Station Processing Facility get ready to move Solar Array Wing-3, a component of the International Space Station, for installation onto the Integrated Electronic Assembly. The solar array is scheduled to be launched on STS-97 in late November along with the P6 truss. The Station's electrical power system (EPS) will use eight photovoltaic solar arrays to convert sunlight to electricity. Each of the eight solar arrays will be 112 feet long by 39 feet wide. The solar arrays are mounted on a '''blanket''' that can be folded like an accordion for delivery. Once in orbit, astronauts will deploy the blankets to their full size. Gimbals will be used to rotate the arrays so that they will face the Sun to provide maximum power to the Space Station.

  20. Solar array development for the surface of Mars

    NASA Technical Reports Server (NTRS)

    Mardesich, N.; Dawson, S.; Rapp, D.; Sharps, Paul; Aiken, D.; Spence, B. R.; White, S. F.; King, R. P.; Edmonson, K.

    2003-01-01

    JPL's missions to Mars have revealed factors that have an adverse impact on the performance of Mars Surface Solar Arrays. These factors included a spectrum shift toward the red wavelengths, atmospheric scattering and absorption and an accumulation of Mars surface dust on the arrays. All of these factors will reduce the power generated from state of the art triple junction solar cells used by earth orbiting satellites. This paper will report the results of JPL supported work conducted by US solar array manufacturers to increase the performance of solar arrays for future Mars surface missions. JPL awarded four vendors contracts to evaluate methods of improving power generation on the surface of Mars. These four contracts cover the redesign of the existing triple junction solar cell, modifying solar simulator output to match the Mars surface spectrum and techniques to control or remove dust from the surface of the arrays. The methodology and results of this evaluation will be presented in this paper.

  1. Advances in Solar Power Forecasting

    NASA Astrophysics Data System (ADS)

    Haupt, S. E.; Kosovic, B.; Drobot, S.

    2014-12-01

    The National Center for Atmospheric Research and partners are building a blended SunCast Solar Power Forecasting system. This system includes several short-range nowcasting models and improves upon longer range numerical weather prediction (NWP) models as part of the "Public-Private-Academic Partnership to Advance Solar Power Forecasting." The nowcasting models being built include statistical learning models that include cloud regime prediction, multiple sky imager-based advection models, satellite image-based advection models, and rapid update NWP models with cloud assimilation. The team has also integrated new modules into the Weather Research and Forecasting Model (WRF) to better predict clouds, aerosols, and irradiance. The modules include a new shallow convection scheme; upgraded physics parameterizations of clouds; new radiative transfer modules that specify GHI, DNI, and DIF prediction; better satellite assimilation methods; and new aerosol estimation methods. These new physical models are incorporated into WRF-Solar, which is then integrated with publically available NWP models via the Dynamic Integrated Forecast (DICast) system as well as the Nowcast Blender to provide seamless forecasts at partner utility and balancing authority commercial solar farms. The improvements will be described and results to date discussed.

  2. Development of Electrostatically Clean Solar Array Panels

    NASA Technical Reports Server (NTRS)

    Stern, Theodore G.

    2000-01-01

    Certain missions require Electrostatically Clean Solar Array (ECSA) panels to establish a favorable environment for the operation of sensitive scientific instruments. The objective of this program was to demonstrate the feasibility of an ECSA panel that minimizes panel surface potential below 100mV in LEO and GEO charged particle environments, prevents exposure of solar cell voltage and panel insulating surfaces to the ambient environment, and provides an equipotential, grounded structure surrounding the entire panel. An ECSA panel design was developed that uses a Front Side Aperture-Shield (FSA) that covers all inter-cell areas with a single graphite composite laminate, composite edge clips for connecting the FSA to the panel substrate, and built-in tabs that interconnect the FSA to conductive coated coverglasses using a conductive adhesive. Analysis indicated the ability of the design to meet the ECSA requirements. Qualification coupons and a 0.5m x 0.5m prototype panel were fabricated and tested for photovoltaic performance and electrical grounding before and after exposure to acoustic and thermal cycling environments. The results show the feasibility of achieving electrostatic cleanliness with a small penalty in mass, photovoltaic performance and cost, with a design is structurally robust and compatible with a wide range of current solar panel technologies.

  3. Low concentration ratio solar array structural configuration

    NASA Technical Reports Server (NTRS)

    Nalbandian, S. J.

    1984-01-01

    The design and structural properties of a low concentration ratio solar array are discussed. The assembled module consists of six interconnected containers which are compactly stowed in a volume of 3.24 m(3) for delivery to orbit by the shuttle. The containers deploy in accordian fashion into a rectangular area of 19.4 x 68 meters and can be attached to the user spacecraft along the longitudinal centerline of the end container housing. Five rotary incremental actuators requiring about 8 watts each will execute the 180-degree rotation at each joint. Deployable masts (three per side) are used to extend endcaps from the housing in both directions. Each direction is extended by three masts requiring about 780 watts for about 27 minutes. Concentrator elements are extended by the endcaps and are supported by cable systems that are connected between the housings and endcaps. These power generating elements contain reflector panels which concentrate light onto the solar panels consisting of an aluminum radiator with solar cells positioned within the element base formed by the reflectors. A flat wire harness collects the power output of individual elements for transfer to the module container housing harnesses.

  4. The ARA Mark 3 solar array design and development

    NASA Technical Reports Server (NTRS)

    vanHassel, Rob H. A.

    1996-01-01

    The ARA (Advanced Rigid Array) Mark3 solar array of Fokker Space BV is currently in its final stages of qualification (wing tests to be completed in March, 1996; unit/part tests in April, 1996). With regard to its predecessor, the ARA Mark2, the design has not only been improved in terms of mechanical and electrical performance, but also with regard to production cost and throughput time. This 'state of the art' array is designed to fit the needs of a wide variety of geostationary telecommunications satellites and is qualified for launch on the complete range of medium/large size commercial launchers (Ariane IV & V, Atlas, Delta, Proton, Long March, H2). The first mission to fly the new ARA Mk3 array is Hot Bird 2 (customer: Eutelsat, prime contractor: Matra Marconi Space; launch: mid-1996). In this configuration, its end of life (EOL) power-to-mass ratio is 42 W/kg, with an operational life of more than 12 years. The main mechanisms on a solar array are typically found in the deployment system and in the hold down and release system. During the design and development phase of these mechanisms, extensive engineering and qualification tests have been performed. This paper presents the key design features of these mechanisms and the improvements that were made with regard to their predecessors. It also describes the qualification philosophy on unit/part and wing level. Finally, some of the development items that turned out to be critical, as well as the lessons learned from them, are discussed.

  5. Enhanced plasma current collection from weakly conducting solar array blankets

    NASA Technical Reports Server (NTRS)

    Hillard, G. Barry

    1993-01-01

    Among the solar cell technologies to be tested in space as part of the Solar Array Module Plasma Interactions Experiment (SAMPIE) will be the Advanced Photovoltaic Solar Array (APSA). Several prototype twelve cell coupons were built for NASA using different blanket materials and mounting techniques. The first conforms to the baseline design for APSA which calls for the cells to be mounted on a carbon loaded Kapton blanket to control charging in GEO. When deployed, this design has a flexible blanket supported around the edges. A second coupon was built with the cells mounted on Kapton-H, which was in turn cemented to a solid aluminum substrate. A final coupon was identical to the latter but used germanium coated Kapton to control atomic oxygen attack in LEO. Ground testing of these coupons in a plasma chamber showed considerable differences in plasma current collection. The Kapton-H coupon demonstrated current collection consistent with exposed interconnects and some degree of cell snapover. The other two coupons experienced anomalously large collection currents. This behavior is believed to be a consequence of enhanced plasma sheaths supported by the weakly conducting carbon and germanium used in these coupons. The results reported here are the first experimental evidence that the use of such materials can result in power losses to high voltage space power systems.

  6. Solar Array in Simulated LEO Plasma Environment

    NASA Technical Reports Server (NTRS)

    Vayner, Boris; Galofaro, Joel; Ferguson, Dale

    2004-01-01

    Six different types of solar arrays have been tested in large vacuum chambers. The low Earth orbit plasma environment was simulated in plasma vacuum chambers, where the parameters could be controlled precisely. Diagnostic equipment included spherical Langmuir probes, mass spectrometer, low-noise CCD camera with optical spectrometer, video camera, very sensitive current probe to measure arc current, and a voltage probe to register variations in a conductor potential. All data (except video) were obtained in digital form that allowed us to study the correlation between external parameters (plasma density, additional capacitance, bias voltage, etc) and arc characteristics (arc rate, arc current pulse width and amplitude, gas species partial pressures, and intensities of spectral lines). Arc inception voltages, arc rates, and current collections are measured for samples with different coverglass materials and thickness, interconnect designs, and cell sizes. It is shown that the array with wrapthrough interconnects have the highest arc threshold and the lowest current collection. Coverglass design with overhang results in decrease of current collection and increase of arc threshold. Doubling coverglass thickness causes the increase in arc inception voltage. Both arc inception voltage and current collection increase significantly with increasing a sample temperature to 80 C. Sustained discharges are initiated between adjacent cells with potential differences of 40 V for the sample with 300 m coverglass thickness and 60 V for the sample with 150 m coverglass thickness. Installation of cryogenic pump in large vacuum chamber provided the possibility of considerable outgassing of array surfaces which resulted in significant decrease of arc rate. Arc sites were determined by employing a video-camera, and it is shown that the most probable sites for arc inception are triple-junctions, even though some arcs were initiated in gaps between cells. It is also shown that the arc

  7. Solar Array in Simulated LEO Plasma Environment

    NASA Technical Reports Server (NTRS)

    Vayner, Boris; Galofaro, Joel; Ferguson, Dale

    2003-01-01

    Six different types of solar arrays have been tested in large vacuum chambers. The low earth orbit plasma environment was simulated in plasma vacuum chambers, where the parameters could be controlled precisely. Diagnostic equipment included spherical Langmuir probes, mass spectrometer, low-noise CCD camera with optical spectrometer, video camera, very sensitive current probe to measure arc current, and a voltage probe to register variations in a conductor potential. All data (except video) were obtained in digital form that allowed us to study the correlation between external parameters (plasma density, additional capacitance, bias voltage, etc) and arc characteristics (arc rate, arc current pulse width and amplitude, gas species partial pressures, and intensities of spectral lines). Arc inception voltages, arc rates, and current selections are measured for samples with different coverglass materials and thickness, interconnect designs, and cell sizes. It is shown that the array with wrapthrough interconnects have the highest arc threshold and the lowest current collection. Coverglass design with overhang results in decrease of current collection and increase of arc threshold. Doubling coverglass thickness cases the increase in arc inception voltage. Both arc inception voltage and current collection increase significantly with increasing a sample temperature to 80 C. Sustained discharges are initiated between adjacent cells with potential differences of 40 V for the sample with 300 micron coverglass thickness and 60 V for the sample with 150 micron coverglass thickness. Installation of cryogenic pump in large vacuum chamber provided the possibility of considerable outgassing of array surfaces which resulted in significant decrease of arc rate. Arc sites were determined by employing a video-camera, and it is shown that the most probable sites for arc inception are triple-junctions, even though some arcs were initiated in gaps between cells. It is also shown that the

  8. Advances in Solar Heating and Cooling Systems

    ERIC Educational Resources Information Center

    Ward, Dan S.

    1976-01-01

    Reports on technological advancements in the fields of solar collectors, thermal storage systems, and solar heating and cooling systems. Diagrams aid in the understanding of the thermodynamics of the systems. (CP)

  9. A 928 sq m (10000 sq ft) solar array

    NASA Technical Reports Server (NTRS)

    Lindberg, D. E.

    1972-01-01

    As the power requirements for space vehicles increases, the area of solar arrays that convert solar energy to usable electrical power increases. The requirements for a 928 sq m (10,000 sq ft) array, its design, and a full-scale demonstration of one quadrant (232 sq m (2500 sq ft)) deployed in a one-g field are described.

  10. A review of the solar array manufacturing industry costing standards

    NASA Technical Reports Server (NTRS)

    1977-01-01

    The solar array manufacturing industry costing standards model is designed to compare the cost of producing solar arrays using alternative manufacturing processes. Constructive criticism of the methodology used is intended to enhance its implementation as a practical design tool. Three main elements of the procedure include workbook format and presentation, theoretical model validity and standard financial parameters.

  11. LSSA (Low-cost Silicon Solar Array) project

    NASA Technical Reports Server (NTRS)

    1976-01-01

    The Photovoltaic Conversion Program was established to find methods of economically generating enough electrical power to meet future requirements. Activities and progress in the following areas are discussed: silicon-refinement processes; silicon-sheet-growth techniques; encapsulants; manufacturing of off-the-shelf solar arrays; and procurement of semistandardized solar arrays.

  12. Solar cells incorporating light harvesting arrays

    DOEpatents

    Lindsey, Jonathan S.; Meyer, Gerald J.

    2002-01-01

    A solar cell incorporates a light harvesting array that comprises: (a) a first substrate comprising a first electrode; and (b) a layer of light harvesting rods electrically coupled to the first electrode, each of the light harvesting rods comprising a polymer of Formula I: X.sup.1.paren open-st.X.sup.m+1).sub.m (I) wherein m is at least 1, and may be from two, three or four to 20 or more; X.sup.1 is a charge separation group (and preferably a porphyrinic macrocycle, which may be one ligand of a double-decker sandwich compound) having an excited-state of energy equal to or lower than that of X.sup.2 ; and X.sup.2 through X.sup.m+1 are chromophores (and again are preferably porphyrinic macrocycles).

  13. Solar cells incorporating light harvesting arrays

    DOEpatents

    Lindsey, Jonathan S.; Meyer, Gerald J.

    2003-07-22

    A solar cell incorporates a light harvesting array that comprises: (a) a first substrate comprising a first electrode; and (b) a layer of light harvesting rods electrically coupled to the first electrode, each of the light harvesting rods comprising a polymer of Formula I: ##EQU1## wherein m is at least 1, and may be from two, three or four to 20 or more; X.sup.1 is a charge separation group (and preferably a porphyrinic macrocycle, which may be one ligand of a double-decker sandwich compound) having an excited-state of energy equal to or lower than that of X.sup.2 ; and X.sup.2 through X.sup.m+1 are chromophores (and again are preferably porphyrinic macrocycles).

  14. Alignment method for solar collector arrays

    DOEpatents

    Driver, Jr., Richard B

    2012-10-23

    The present invention is directed to an improved method for establishing camera fixture location for aligning mirrors on a solar collector array (SCA) comprising multiple mirror modules. The method aligns the mirrors on a module by comparing the location of the receiver image in photographs with the predicted theoretical receiver image location. To accurately align an entire SCA, a common reference is used for all of the individual module images within the SCA. The improved method can use relative pixel location information in digital photographs along with alignment fixture inclinometer data to calculate relative locations of the fixture between modules. The absolute locations are determined by minimizing alignment asymmetry for the SCA. The method inherently aligns all of the mirrors in an SCA to the receiver, even with receiver position and module-to-module alignment errors.

  15. Active Vibration Damping of Solar Arrays

    NASA Astrophysics Data System (ADS)

    Reinicke, Gunar; Baier, Horst; Grillebeck, Anton; Scharfeld, Frank; Hunger, Joseph; Abou-El-Ela, A.; Lohberg, Andreas

    2012-07-01

    Current generations of large solar array panels are lightweight and flexible constructions to reduce net masses. They undergo strong vibrations during launch. The active vibration damping is one convenient option to reduce vibration responses and limit stresses in facesheets. In this study, two actuator concepts are used for vibration damping. A stack interface actuator replaces a panel hold down and is decoupled from bending moments and shear forces. Piezoelectric patch actuators are used as an alternative, where the number, position and size of actuators are mainly driven by controllability analyses. Linear Quadratic Gaussian control is used to attenuate vibrations of selected mode shapes with both actuators. Simulations as well as modal and acoustic tests show the feasibility of selected actuator concepts.

  16. Genesis Solar Wind Array Collector Cataloging Status

    NASA Technical Reports Server (NTRS)

    Burkett, P.J.; Rodriguez, M.C.; Calaway, M.C.; Allton, J.H.

    2009-01-01

    Genesis solar wind array collectors were fractured upon landing hard in Utah in 2004. The fragments were retrieved from the damaged canister, imaged, repackaged and shipped to the Johnson Space Center curatorial facility [1]. As of January 2009, the collection consists of 3460 samples. Of these, 442 are comprised into "multiple" sample groupings, either affixed to adhesive paper (177) or collected in jars (17), culture trays (87), or sets of polystyrene vials (161). A focused characterization task was initiated in May 2008 to document the largest samples in the collection. The task consisted of two goals: to document sapphire based fragments greater than 2 cm in one dimension, and to document silicon based fragments greater than 1 cm in one direction.

  17. Solar Concentrator Advanced Development Program

    NASA Technical Reports Server (NTRS)

    Knasel, Don; Ehresman, Derik

    1989-01-01

    The Solar Concentrator Advanced Development Project has successfully designed, fabricated, and tested a full scale prototypical solar dynamic concentrator for space station applications. A Truss Hexagonal Panel reflector was selected as a viable solar concentrator concept to be used for space station applications. This concentrator utilizes a modular design approach and is flexible in attainable flux profiles and assembly techniques. The detailed design of the concentrator, which included structural, thermal and optical analysis, identified the feasibility of the design and specific technologies that were required to fabricate it. The needed surface accuracy of the reflectors surface was found to be very tight, within 5 mrad RMS slope error, and results in very close tolerances for fabrication. To meet the design requirements, a modular structure composed of hexagonal panels was used. The panels, made up of graphite epoxy box beams provided the strength, stiffness and dimensional stability needed. All initial project requirements were met or exceeded by hardware demonstration. Initial testing of structural repeatability of a seven panel portion of the concentrator was followed by assembly and testing of the full nineteen panel structure. The testing, which consisted of theodolite and optical measurements over an assembly-disassembly-reassembly cycle, demonstrated that the concentrator maintained the as-built contour and optical characteristics. The facet development effort within the project, which included developing the vapor deposited reflective facet, produced a viable design with demonstrated optical characteristics that are within the project goals.

  18. The Submillimeter Wave Astronomy Satellite (SWAS) solar array system

    NASA Technical Reports Server (NTRS)

    Sneiderman, Gary

    1993-01-01

    The SWAS (Submillimeter Wave Astronomy Satellite) solar array system is described. It is an innovative approach to meet the missions requirements. The SWAS satellite provides a three axis stabilized platform to survey a variety of galactic cloud structures. This system includes highly reliable, lightweight launch latch, deployment, and lock mechanisms, and solar array panels that provide the maximum solar cell area. The design of the solar arrays are the result of system trades that included instrument and spacecraft thermal constraints, attitude control system maneuvering rates and pointing accuracies, the power system, and the spacecraft structure.

  19. Phoenix Mars Lander with Solar Arrays Open

    NASA Technical Reports Server (NTRS)

    2006-01-01

    NASA's next Mars-bound spacecraft, the Phoenix Mars Lander, was partway through assembly and testing at Lockheed Martin Space Systems, Denver, in September 2006, progressing toward an August 2007 launch from Florida. In this photograph, spacecraft specialists work on the lander after its fan-like circular solar arrays have been spread open for testing. The arrays will be in this configuration when the spacecraft is active on the surface of Mars.

    Phoenix will land in icy soils near the north polar permanent ice cap of Mars and explore the history of the water in these soils and any associated rocks, while monitoring polar climate. It will dig into the surface, test scooped-up samples for carbon-bearing compounds and serve as NASA's first exploration of a potential modern habitat on Mars.

    The Phoenix mission is led by Principal Investigator Peter H. Smith of the University of Arizona, Tucson, with project management at NASA's Jet Propulsion Laboratory and development partnership with Lockheed Martin Space Systems. International contributions for Phoenix are provided by the Canadian Space Agency, the University of Neuchatel (Switzerland), the University of Copenhagen, and the Max Planck Institute in Germany. JPL is a division of the California Institute of Technology in Pasadena.

  20. Alphabus Solar Array- Versatile and Powerful Solar Arrays for Tomorrow's Commercial Telecom Satellites

    NASA Astrophysics Data System (ADS)

    Pfefferkorn, T.; Oxynos, C.; Greff, P.; Gerlach, L.

    2008-09-01

    After the successful series of Eurostar 3000 and Spacebus 4000 satellites and due to the demand of satellite operators for even larger and more powerful satellites, ESA decided to co-fund the development of a new satellite platform which covers the market segment beyond the upper limits of both satellite families.The new satellite bus family Alphabus is developed in the frame of ARTES 8 project by a joint project team of ASTRIUM and TAS, whereas the solar array is developed by ASTRIUM GmbH.The main approaches in this design phase for the Alphabus solar array were to find a standardized and scaleable design to production and to use qualification heritage from former projects, especially Eurostar 3000, as far as possible. The main challenges for the solar array design and test philosophy were the usage of lateral deployment and related sequential deployment and the bus voltage of 102,5V and related ESD precautions.This paper provides an overview of the different configurations, their main design features and performance parameters. In addition it summarizes the development and verification approach and shows the actual qualification status.

  1. Promising Results from Three NASA SBIR Solar Array Technology Development Programs

    NASA Technical Reports Server (NTRS)

    Eskenazi, Mike; White, Steve; Spence, Brian; Douglas, Mark; Glick, Mike; Pavlick, Ariel; Murphy, David; O'Neill, Mark; McDanal, A. J.; Piszczor, Michael

    2005-01-01

    Results from three NASA SBIR solar array technology programs are presented. The programs discussed are: 1) Thin Film Photovoltaic UltraFlex Solar Array; 2) Low Cost/Mass Electrostatically Clean Solar Array (ESCA); and 3) Stretched Lens Array SquareRigger (SLASR). The purpose of the Thin Film UltraFlex (TFUF) Program is to mature and validate the use of advanced flexible thin film photovoltaics blankets as the electrical subsystem element within an UltraFlex solar array structural system. In this program operational prototype flexible array segments, using United Solar amorphous silicon cells, are being manufactured and tested for the flight qualified UltraFlex structure. In addition, large size (e.g. 10 kW GEO) TFUF wing systems are being designed and analyzed. Thermal cycle and electrical test and analysis results from the TFUF program are presented. The purpose of the second program entitled, Low Cost/Mass Electrostatically Clean Solar Array (ESCA) System, is to develop an Electrostatically Clean Solar Array meeting NASA s design requirements and ready this technology for commercialization and use on the NASA MMS and GED missions. The ESCA designs developed use flight proven materials and processes to create a ESCA system that yields low cost, low mass, high reliability, high power density, and is adaptable to any cell type and coverglass thickness. All program objectives, which included developing specifications, creating ESCA concepts, concept analysis and trade studies, producing detailed designs of the most promising ESCA treatments, manufacturing ESCA demonstration panels, and LEO (2,000 cycles) and GEO (1,350 cycles) thermal cycling testing of the down-selected designs were successfully achieved. The purpose of the third program entitled, "High Power Platform for the Stretched Lens Array," is to develop an extremely lightweight, high efficiency, high power, high voltage, and low stowed volume solar array suitable for very high power (multi-kW to MW

  2. Spraylon fluorocarbon encapsulation for silicon solar cell arrays

    NASA Technical Reports Server (NTRS)

    1977-01-01

    A development program was performed for evaluating, modifying, and optimizing the Lockheed formulated liquid transparent filmforming Spraylon fluorocarbon protective coating for silicon solar cells and modules. The program objectives were designed to meet the requirements of the low-cost automated solar cell array fabrication process. As part of the study, a computer program was used to establish the limits of the safe working stress in the coated silicon solar cell array system under severe thermal shock.

  3. Advancing Concentrating Solar Power Research (Fact Sheet)

    SciTech Connect

    Not Available

    2014-02-01

    Researchers at the National Renewable Energy Laboratory (NREL) provide scientific, engineering, and analytical expertise to help advance innovation in concentrating solar power (CSP). This fact sheet summarizes how NREL is advancing CSP research.

  4. Array Automated Assembly Task Low Cost Silicon Solar Array Project, Phase 2

    NASA Technical Reports Server (NTRS)

    Rhee, S. S.; Jones, G. T.; Allison, K. L.

    1978-01-01

    Progress in the development of solar cells and module process steps for low-cost solar arrays is reported. Specific topics covered include: (1) a system to automatically measure solar cell electrical performance parameters; (2) automation of wafer surface preparation, printing, and plating; (3) laser inspection of mechanical defects of solar cells; and (4) a silicon antireflection coating system. Two solar cell process steps, laser trimming and holing automation and spray-on dopant junction formation, are described.

  5. AGATA—Advanced GAmma Tracking Array

    NASA Astrophysics Data System (ADS)

    Akkoyun, S.; Algora, A.; Alikhani, B.; Ameil, F.; de Angelis, G.; Arnold, L.; Astier, A.; Ataç, A.; Aubert, Y.; Aufranc, C.; Austin, A.; Aydin, S.; Azaiez, F.; Badoer, S.; Balabanski, D. L.; Barrientos, D.; Baulieu, G.; Baumann, R.; Bazzacco, D.; Beck, F. A.; Beck, T.; Bednarczyk, P.; Bellato, M.; Bentley, M. A.; Benzoni, G.; Berthier, R.; Berti, L.; Beunard, R.; Lo Bianco, G.; Birkenbach, B.; Bizzeti, P. G.; Bizzeti-Sona, A. M.; Le Blanc, F.; Blasco, J. M.; Blasi, N.; Bloor, D.; Boiano, C.; Borsato, M.; Bortolato, D.; Boston, A. J.; Boston, H. C.; Bourgault, P.; Boutachkov, P.; Bouty, A.; Bracco, A.; Brambilla, S.; Brawn, I. P.; Brondi, A.; Broussard, S.; Bruyneel, B.; Bucurescu, D.; Burrows, I.; Bürger, A.; Cabaret, S.; Cahan, B.; Calore, E.; Camera, F.; Capsoni, A.; Carrió, F.; Casati, G.; Castoldi, M.; Cederwall, B.; Cercus, J.-L.; Chambert, V.; El Chambit, M.; Chapman, R.; Charles, L.; Chavas, J.; Clément, E.; Cocconi, P.; Coelli, S.; Coleman-Smith, P. J.; Colombo, A.; Colosimo, S.; Commeaux, C.; Conventi, D.; Cooper, R. J.; Corsi, A.; Cortesi, A.; Costa, L.; Crespi, F. C. L.; Cresswell, J. R.; Cullen, D. M.; Curien, D.; Czermak, A.; Delbourg, D.; Depalo, R.; Descombes, T.; Désesquelles, P.; Detistov, P.; Diarra, C.; Didierjean, F.; Dimmock, M. R.; Doan, Q. T.; Domingo-Pardo, C.; Doncel, M.; Dorangeville, F.; Dosme, N.; Drouen, Y.; Duchêne, G.; Dulny, B.; Eberth, J.; Edelbruck, P.; Egea, J.; Engert, T.; Erduran, M. N.; Ertürk, S.; Fanin, C.; Fantinel, S.; Farnea, E.; Faul, T.; Filliger, M.; Filmer, F.; Finck, Ch.; de France, G.; Gadea, A.; Gast, W.; Geraci, A.; Gerl, J.; Gernhäuser, R.; Giannatiempo, A.; Giaz, A.; Gibelin, L.; Givechev, A.; Goel, N.; González, V.; Gottardo, A.; Grave, X.; Grebosz, J.; Griffiths, R.; Grint, A. N.; Gros, P.; Guevara, L.; Gulmini, M.; Görgen, A.; Ha, H. T. M.; Habermann, T.; Harkness, L. J.; Harroch, H.; Hauschild, K.; He, C.; Hernández-Prieto, A.; Hervieu, B.; Hess, H.; Hüyük, T.; Ince, E.; Isocrate, R.; Jaworski, G.; Johnson, A.; Jolie, J.; Jones, P.; Jonson, B.; Joshi, P.; Judson, D. S.; Jungclaus, A.; Kaci, M.; Karkour, N.; Karolak, M.; Kaşkaş, A.; Kebbiri, M.; Kempley, R. S.; Khaplanov, A.; Klupp, S.; Kogimtzis, M.; Kojouharov, I.; Korichi, A.; Korten, W.; Kröll, Th.; Krücken, R.; Kurz, N.; Ky, B. Y.; Labiche, M.; Lafay, X.; Lavergne, L.; Lazarus, I. H.; Leboutelier, S.; Lefebvre, F.; Legay, E.; Legeard, L.; Lelli, F.; Lenzi, S. M.; Leoni, S.; Lermitage, A.; Lersch, D.; Leske, J.; Letts, S. C.; Lhenoret, S.; Lieder, R. M.; Linget, D.; Ljungvall, J.; Lopez-Martens, A.; Lotodé, A.; Lunardi, S.; Maj, A.; van der Marel, J.; Mariette, Y.; Marginean, N.; Marginean, R.; Maron, G.; Mather, A. R.; Meçzyński, W.; Mendéz, V.; Medina, P.; Melon, B.; Menegazzo, R.; Mengoni, D.; Merchan, E.; Mihailescu, L.; Michelagnoli, C.; Mierzejewski, J.; Milechina, L.; Million, B.; Mitev, K.; Molini, P.; Montanari, D.; Moon, S.; Morbiducci, F.; Moro, R.; Morrall, P. S.; Möller, O.; Nannini, A.; Napoli, D. R.; Nelson, L.; Nespolo, M.; Ngo, V. L.; Nicoletto, M.; Nicolini, R.; Le Noa, Y.; Nolan, P. J.; Norman, M.; Nyberg, J.; Obertelli, A.; Olariu, A.; Orlandi, R.; Oxley, D. C.; Özben, C.; Ozille, M.; Oziol, C.; Pachoud, E.; Palacz, M.; Palin, J.; Pancin, J.; Parisel, C.; Pariset, P.; Pascovici, G.; Peghin, R.; Pellegri, L.; Perego, A.; Perrier, S.; Petcu, M.; Petkov, P.; Petrache, C.; Pierre, E.; Pietralla, N.; Pietri, S.; Pignanelli, M.; Piqueras, I.; Podolyak, Z.; Le Pouhalec, P.; Pouthas, J.; Pugnére, D.; Pucknell, V. F. E.; Pullia, A.; Quintana, B.; Raine, R.; Rainovski, G.; Ramina, L.; Rampazzo, G.; La Rana, G.; Rebeschini, M.; Recchia, F.; Redon, N.; Reese, M.; Reiter, P.; Regan, P. H.; Riboldi, S.; Richer, M.; Rigato, M.; Rigby, S.; Ripamonti, G.; Robinson, A. P.; Robin, J.; Roccaz, J.; Ropert, J.-A.; Rossé, B.; Rossi Alvarez, C.; Rosso, D.; Rubio, B.; Rudolph, D.; Saillant, F.; Şahin, E.; Salomon, F.; Salsac, M.-D.; Salt, J.; Salvato, G.; Sampson, J.; Sanchis, E.; Santos, C.; Schaffner, H.; Schlarb, M.; Scraggs, D. P.; Seddon, D.; Şenyiğit, M.; Sigward, M.-H.; Simpson, G.; Simpson, J.; Slee, M.; Smith, J. F.; Sona, P.; Sowicki, B.; Spolaore, P.; Stahl, C.; Stanios, T.; Stefanova, E.; Stézowski, O.; Strachan, J.; Suliman, G.; Söderström, P.-A.; Tain, J. L.; Tanguy, S.; Tashenov, S.; Theisen, Ch.; Thornhill, J.; Tomasi, F.; Toniolo, N.; Touzery, R.; Travers, B.; Triossi, A.; Tripon, M.; Tun-Lanoë, K. M. M.; Turcato, M.; Unsworth, C.; Ur, C. A.; Valiente-Dobon, J. J.; Vandone, V.; Vardaci, E.; Venturelli, R.; Veronese, F.; Veyssiere, Ch.; Viscione, E.; Wadsworth, R.; Walker, P. M.; Warr, N.; Weber, C.; Weisshaar, D.; Wells, D.; Wieland, O.; Wiens, A.; Wittwer, G.; Wollersheim, H. J.; Zocca, F.; Zamfir, N. V.; Ziebliński, M.; Zucchiatti, A.

    2012-03-01

    The Advanced GAmma Tracking Array (AGATA) is a European project to develop and operate the next generation γ-ray spectrometer. AGATA is based on the technique of γ-ray energy tracking in electrically segmented high-purity germanium crystals. This technique requires the accurate determination of the energy, time and position of every interaction as a γ ray deposits its energy within the detector volume. Reconstruction of the full interaction path results in a detector with very high efficiency and excellent spectral response. The realisation of γ-ray tracking and AGATA is a result of many technical advances. These include the development of encapsulated highly segmented germanium detectors assembled in a triple cluster detector cryostat, an electronics system with fast digital sampling and a data acquisition system to process the data at a high rate. The full characterisation of the crystals was measured and compared with detector-response simulations. This enabled pulse-shape analysis algorithms, to extract energy, time and position, to be employed. In addition, tracking algorithms for event reconstruction were developed. The first phase of AGATA is now complete and operational in its first physics campaign. In the future AGATA will be moved between laboratories in Europe and operated in a series of campaigns to take advantage of the different beams and facilities available to maximise its science output. The paper reviews all the achievements made in the AGATA project including all the necessary infrastructure to operate and support the spectrometer.

  6. Improved solar array power point model with SPICE realization

    SciTech Connect

    Glass, M.C.

    1996-12-31

    An improved and simplified formulation is given for a solar array current-voltage model. This model curve matches a specified maximum power point (i,v) specification, in addition to the open-circuit and short-circuit specifications. The improved model has a simplified numerical solution, which is practical for SPICE simulation of orbital-scale electrical power systems. This paper presents the mathematical development of the solar array model solution, and the form of the necessary Newton/Raphson equations. The iterative nonlinear solution is then realized in a SPICE model of the solar array, which is then demonstrated in an orbital-time-scale satellite power system simulation.

  7. Research on Mitigation Method against Secondary Arcing on Solar Array

    NASA Astrophysics Data System (ADS)

    Wada, Tomohiro; Masui, Hirokazu; Toyoda, Kazuhiro; Cho, Mengu

    The recent trend of satellite manufacturing is to increase its communication capacity, multi-purpose mission payload, electric power and lifetime. A short-circuit due to discharge on the solar array of the satellite hampers its target by causing serious problems, such as, lowering of power generation that ultimately halts the operation of solar array. In this paper, we have investigated possible mitigation methods against short-circuit due to discharge on solar array by applying coating and by changing the shape of Room Temperature Vulcanization: Silicon adhesive (RTV). The electrostatic discharge is mitigated by obtaining the event of secondary arc generated on each condition.

  8. A solar array module fabrication process for HALE solar electric UAVs

    SciTech Connect

    Carey, P.G.; Aceves, R.C.; Colella, N.J.; Thompson, J.B.; Williams, K.A.

    1993-12-01

    We describe a fabrication process to manufacture high power to weight ratio flexible solar array modules for use on high altitude long endurance (HALE) solar electric unmanned air vehicles (UAVs). A span-loaded flying wing vehicle, known as the RAPTOR Pathfinder, is being employed as a flying test bed to expand the envelope of solar powered flight to high altitudes. It requires multiple light weight flexible solar array modules able to endure adverse environmental conditions. At high altitudes the solar UV flux is significantly enhanced relative to sea level, and extreme thermal variations occur. Our process involves first electrically interconnecting solar cells into an array followed by laminating them between top and bottom laminated layers into a solar array module. After careful evaluation of candidate polymers, fluoropolymer materials have been selected as the array laminate layers because of their inherent abilities to withstand the hostile conditions imposed by the environment.

  9. Optical Design of Segmented Hexagon Array Solar Mirror

    NASA Technical Reports Server (NTRS)

    Huegele, Vince

    2000-01-01

    A segmented array of mirrors was designed for a solar concentrator test stand at MSFC for firing solar thermal propulsion engines. The 144 mirrors each have a spherical surface to approximate a parabolic concentrator when combined into the entire 18-foot diameter array. The mirror segments are aluminum hexagons that had the surface diamond turned and quartz coated. The array focuses sunlight reflected from a heliostat to a 4 inch diameter spot containing 10 kw of power at the 15-foot focal point. The derivation of the surface figure for the respective mirror elements is shown. The alignment process of the array is discussed and test results of the system's performance is given.

  10. Gravity Probe B Completed With Solar Arrays

    NASA Technical Reports Server (NTRS)

    2004-01-01

    In this photo, the Gravity Probe B (GP-B) space vehicle is completed during the solar array installation. The GP-B is the relativity experiment developed at Stanford University to test two extraordinary predictions of Albert Einstein's general theory of relativity. The experiment will measure, very precisely, the expected tiny changes in the direction of the spin axes of four gyroscopes contained in an Earth-orbiting satellite at a 400-mile altitude. So free are the gyroscopes from disturbance that they will provide an almost perfect space-time reference system. They will measure how space and time are very slightly warped by the presence of the Earth, and, more profoundly, how the Earth's rotation very slightly drags space-time around with it. These effects, though small for the Earth, have far-reaching implications for the nature of matter and the structure of the Universe. GP-B is among the most thoroughly researched programs ever undertaken by NASA. This is the story of a scientific quest in which physicists and engineers have collaborated closely over many years. Inspired by their quest, they have invented a whole range of technologies that are already enlivening other branches of science and engineering. GP-B is scheduled for launch in April 2004 and managed for NASA by the Marshall Space Flight Center. Development of the GP-B is the responsibility of Stanford University along with major subcontractor Lockheed Martin Corporation. (Image credit to Russ Underwood, Lockheed Martin Corporation).

  11. Solar Observations with the Atacama Large Millimeter/submillimeter Array

    NASA Astrophysics Data System (ADS)

    Wedemeyer, Sven

    2015-08-01

    The interferometric Atacama Large Millimeter/submillimeter Array (ALMA) has already demonstrated its impressive capabilities by observing a large variety of targets ranging from protoplanetary disks to galactic nuclei. ALMA is also capable of observing the Sun and has been used for five solar test campaigns so far. The technically challenging solar observing modes are currently under development and regular observations are expected to begin in late 2016.ALMA consists of 66 antennas located in the Chilean Andes at an altitude of 5000 m and is a true leap forward in terms of spatial resolution at millimeter wavelengths. The resolution of reconstructed interferometric images of the Sun is anticipated to be close to what current optical solar telescopes can achieve. In combination with the high temporal and spectral resolution, these new capabilities open up new parameter spaces for solar millimeter observations.The solar radiation at wavelengths observed by ALMA originates from the chromosphere, where the height of the sampled layer increases with selected wavelength. The continuum intensity is linearly correlated to the local gas temperature in the probed layer, which makes ALMA essentially a linear thermometer. During flares, ALMA can detect additional non-thermal emission contributions. Measurements of the polarization state facilitate the valuable determination of the chromospheric magnetic field. In addition, spectrally resolved observations of radio recombination and molecular lines may yield great diagnostic potential, which has yet to be investigated and developed.Many different scientific applications for a large range of targets from quiet Sun to active regions and prominences are possible, ranging from ultra-high cadence wave studies to flare observations. ALMA, in particular in combination with other ground-based and space-borne instruments, will certainly lead to fascinating new findings, which will advance our understanding of the atmosphere of our Sun

  12. Space solar array reliability: A study and recommendations

    NASA Astrophysics Data System (ADS)

    Brandhorst, Henry W., Jr.; Rodiek, Julie A.

    2008-12-01

    Providing reliable power over the anticipated mission life is critical to all satellites; therefore solar arrays are one of the most vital links to satellite mission success. Furthermore, solar arrays are exposed to the harshest environment of virtually any satellite component. In the past 10 years 117 satellite solar array anomalies have been recorded with 12 resulting in total satellite failure. Through an in-depth analysis of satellite anomalies listed in the Airclaim's Ascend SpaceTrak database, it is clear that solar array reliability is a serious, industry-wide issue. Solar array reliability directly affects the cost of future satellites through increased insurance premiums and a lack of confidence by investors. Recommendations for improving reliability through careful ground testing, standardization of testing procedures such as the emerging AIAA standards, and data sharing across the industry will be discussed. The benefits of creating a certified module and array testing facility that would certify in-space reliability will also be briefly examined. Solar array reliability is an issue that must be addressed to both reduce costs and ensure continued viability of the commercial and government assets on orbit.

  13. Daytime Solar Heating of Photovoltaic Arrays in Low Density Plasmas

    NASA Technical Reports Server (NTRS)

    Galofaro, J.; Vayner, B.; Ferguson, D.

    2003-01-01

    The purpose of the current work is to determine the out-gassing rate of H2O molecules for a solar array placed under daytime solar heating (full sunlight) conditions typically encountered in a Low Earth Orbital (LEO) environment. Arc rates are established for individual arrays held at 14 C and are used as a baseline for future comparisons. Radiated thermal solar flux incident to the array is simulated by mounting a stainless steel panel equipped with resistive heating elements several centimeters behind the array. A thermal plot of the heater plate temperature and the array temperature as a function of heating time is then obtained. A mass spectrometer is used to record the levels of partial pressure of water vapor in the test chamber after each of the 5 heating/cooling cycles. Each of the heating cycles was set to time duration of 40 minutes to simulate the daytime solar heat flux to the array over a single orbit. Finally the array is cooled back to ambient temperature after 5 complete cycles and the arc rates of the solar arrays is retested. A comparison of the various data is presented with rather some unexpected results.

  14. Hydraulic Performance of a Multistage Array of Advanced Centrifugal Contactors

    SciTech Connect

    Hodges, M.E.

    2001-05-29

    The hydraulic characteristics of an advanced design centrifugal contactor array have been determined at the Savannah River Laboratory (SRL). The advanced design utilizes couette mixing (Taylor vortices) in the annulus between the rotating and stationary bowls. Excellent phase separation over a wide range of flow conditions was obtained. Interfaces within an entire eight-stage array were controlled with a single weir air pressure.

  15. Proceedings of the Flat-Plate Solar Array Project Research Forum on Photovoltaic Metallization Systems

    NASA Technical Reports Server (NTRS)

    1983-01-01

    A photovoltaic Metallization Research forum, under the sponsorship of the Flat-Plate Solar Array Project consisted of five sessions, covering: (1) the current status of metallization systems, (2) system design, (3) thick-film metallization, (4) advanced techniques, and (5) future metallization challenges.

  16. Parasitic current collection by PASP Plus solar arrays

    NASA Astrophysics Data System (ADS)

    Davis, Victoria Ann; Gardner, Barbara M.

    1995-10-01

    Solar cells at potentials positive with respect to a surrounding plasma collect electrons. Current is collected by the exposed high voltage surfaces: the interconnects and the sides of the solar cells. This current is a drain on the array power that can be significant for high-power arrays. In addition, this current influences the current balance that determines the floating potential of the spacecraft. One of the objectives of the Air Force (PL/GPS) PASP Plus (Photovoltaic Array Space Power Plus Diagnostics) experiment is an improved understanding fo parasitic current collection. We have done computer modeling of parasitic current collection and have examined current collection flight data from the first year of operations. Prior to the flight we did computer modeling to improve our understanding of the physical processes that control parasitic current collection. At high potentials, the current rapidly rises due to a phenomenon called snapover. Under snapover conditions, the equilibrium potential distribution across the dielectric surface is such that part of the area is at potentials greater than the first crossover of the secondary yield curve. Therefore, each incident electron generates more than one secondary electron. The net effect is that the high potential area and the collecting area increase. We did two-dimensional calculations for the various geometries to be flown. The calculations span the space of anticipated plasma conditions, applied potential, and material parameters. We used the calculations and early flight data to develop an analytic formula for the dependence of the current on the primary problem variables. The analytic formula was incorporated into the EPSAT computer code. EPSAT allows us to easily extend the results to other conditions. PASP Plus is the principal experiment integrated onto the Advanced Photovoltaic and Electronics Experiments (APEX) satellite bus. The experiment is testing twelve different solar array designs.

  17. Solar array deployment qualification for the LMX of buses

    NASA Astrophysics Data System (ADS)

    Lee, Kathy

    2005-07-01

    The solar array deployment system for the LMX line of buses deploys rigid Solar Array Wing Assemblies (SAWAs). Each SAWA has a set of Solar Array Deployment Mechanisms (SADM), which consists of two hinges, a strut, and two Hold Down Release Mechanisms (HDRMs). To qualify the SADM for flight, each mechanism component was qualified individually, then assembled to a qualification SAWA on Special Test Equipment (STE) and deployed in a thermal vacuum chamber at ambient, hot, and cold temperatures. These mechanisms were designed, built, and tested by the Power and Mechanisms part of the Power, Thermal, Structures & Mechanisms Product Center, which develops products for both internal and external customers. This paper will discuss the qualification effort for the LMX Solar Array deployment, including qualification hardware and STE. It will focus on unique challenges presented by each aspect of the qualification, and lessons learned from the hardware integration and the qualification testing.

  18. Locking Corners Speed Solar-Array Frame Assembly

    NASA Technical Reports Server (NTRS)

    Olah, S.; Sampson, W. J.

    1984-01-01

    Mitered corners of solar-array frames joined together by single angle brace and two springs. Locking corner braces and mating frame members pushed together by hand or assembled automatically. Fastening system used to assemble window screens and picture frames.

  19. Proceedings of the Low-Cost Solar Array Wafering Workshop

    NASA Technical Reports Server (NTRS)

    Morrison, A. D.

    1982-01-01

    The technology and economics of silicon ingot wafering for low cost solar arrays were discussed. Fixed and free abrasive sawing wire, ID, and multiblade sawing, materials, mechanisms, characterization, and innovative concepts were considered.

  20. Beam-Forming Concentrating Solar Thermal Array Power Systems

    NASA Technical Reports Server (NTRS)

    Cwik, Thomas A. (Inventor); Dimotakis, Paul E. (Inventor); Hoppe, Daniel J. (Inventor)

    2016-01-01

    The present invention relates to concentrating solar-power systems and, more particularly, beam-forming concentrating solar thermal array power systems. A solar thermal array power system is provided, including a plurality of solar concentrators arranged in pods. Each solar concentrator includes a solar collector, one or more beam-forming elements, and one or more beam-steering elements. The solar collector is dimensioned to collect and divert incoming rays of sunlight. The beam-forming elements intercept the diverted rays of sunlight, and are shaped to concentrate the rays of sunlight into a beam. The steering elements are shaped, dimensioned, positioned, and/or oriented to deflect the beam toward a beam output path. The beams from the concentrators are converted to heat at a receiver, and the heat may be temporarily stored or directly used to generate electricity.

  1. Maximum power transfer from a solar-cell array by sensing array temperature

    NASA Technical Reports Server (NTRS)

    Sussman, M.

    1972-01-01

    A technique is described in which a spacecraft solar-cell array is caused to operate at or near maximum power output over a wide range of environmental conditions. The output of an array temperature sensor is used to vary the duty cycle of a pulse-width-modulated impedance regulator so that the array operates at the voltage of maximum power. A resistance-type temperature sensor was found to be applicable for most spacecraft missions. However, a solar cell used as a temperature sensor has the advantage of negligible transient errors on lightweight arrays for orbiting spacecraft.

  2. Feasibility study of a 110 watt per kilogram lightweight solar array system

    NASA Technical Reports Server (NTRS)

    Shepard, N. F.; Stahle, C. V.; Hanson, K. L.; Schneider, A.; Blomstrom, L. E.; Hansen, W. T.; Kirpich, A.

    1973-01-01

    The feasibility of a 10,000 watt solar array panel which has a minimum power-to-mass ratio of 110 watt/kg is discussed. The application of this ultralightweight solar array to three possible missions was investigated. With the interplanetary mission as a baseline, the constraining requirements for a geosynchronous mission and for a manned space station mission are presented. A review of existing lightweight solar array system concepts revealed that changes in the system approach are necessary to achieve the specified 110 watt/kg goal. A comprehensive review of existing component technology is presented in the areas of thin solar cells, solar cell covers, welded interconnectors, substrates and deployable booms. Advances in the state-of-the-art of solar cell and deployable boom technology were investigated. System level trade studies required to select the optimum boom bending stiffness, system aspect ratio, bus voltage level, and solar cell circuit arrangement are reported. Design analysis tasks included the thermal analysis of the solar cell blanket, thermal stress analysis of the solar cell interconnectors/substrate, and the thermostructural loading of the deployed boom.

  3. Contaminated Solar Array Handrail Samples Retrieved From Mir Analyzed

    NASA Technical Reports Server (NTRS)

    deGroh, Kim K.; McCue, Terry R.

    2000-01-01

    In January 1998 during the shuttle STS 89 mission, an eight-section Russian solar array panel was retrieved after more than 10 years of exposure to the orbital space environment on Mir. The array was deployed June 16, 1987, and removed on November 3, 1997. It had been actively used as a source of electrical power for 8 years. This operational array had been located on the Mir core module, located directly above the Kvant-2 module. Its retrieval provided a unique opportunity to study the effects of the low-Earth-orbit environment on a functional solar array. The intact solar array underwent scientific inspections and preliminary tests by a joint team of U.S. and Russian investigators to evaluate the effects of long-term space exposure. Upon initial examination, significant contamination was observed over most components of the array. One panel, panel 8, was provided to the U.S. scientists for further evaluation. As part of the U.S. investigations, two solar array handrail samples from panel 8 were evaluated for contamination at the NASA Glenn Research Center at Lewis Field. One is a section of a rigid handrail, and the other is a section of woven fabric tape that was overwrapped around a flexible handhold. Both the flexible handhold woven fabric and the rigid handrail were significantly darkened after 10 years of space exposure. They were evaluated with optical microscopy, field emission scanning electron microscopy (FESEM), and energy-dispersive spectroscopy. Solar absorptance and room-temperature emittance values also were obtained. The returned contaminated solar array segment is very similar in design to the solar arrays being supplied by the Russians for the International Space Station. Therefore, it was desirable to determine what the contaminants on various surfaces are and what the sources of the contamination were.

  4. LSSA (Low-cost Silicon Solar Array) project

    NASA Technical Reports Server (NTRS)

    1976-01-01

    Methods are explored for economically generating electrical power to meet future requirements. The Low-Cost Silicon Solar Array Project (LSSA) was established to reduce the price of solar arrays by improving manufacturing technology, adapting mass production techniques, and promoting user acceptance. The new manufacturing technology includes the consideration of new silicon refinement processes, silicon sheet growth techniques, encapsulants, and automated assembly production being developed under contract by industries and universities.

  5. Thin-Film Solar Array Earth Orbit Mission Applicability Assessment

    NASA Technical Reports Server (NTRS)

    Hoffman, David J.; Kerslake, Thomas W.; Hepp, Aloysius F.; Raffaelle, Ryne P.

    2002-01-01

    This is a preliminary assessment of the applicability and spacecraft-level impact of using very lightweight thin-film solar arrays with relatively large deployed areas for representative Earth orbiting missions. The most and least attractive features of thin-film solar arrays are briefly discussed. A simple calculation is then presented illustrating that from a solar array alone mass perspective, larger arrays with less efficient but lighter thin-film solar cells can weigh less than smaller arrays with more efficient but heavier crystalline cells. However, a proper spacecraft-level systems assessment must take into account the additional mass associated with solar array deployed area: the propellant needed to desaturate the momentum accumulated from area-related disturbance torques and to perform aerodynamic drag makeup reboost. The results for such an assessment are presented for a representative low Earth orbit (LEO) mission, as a function of altitude and mission life, and a geostationary Earth orbit (GEO) mission. Discussion of the results includes a list of specific mission types most likely to benefit from using thin-film arrays. NASA Glenn's low-temperature approach to depositing thin-film cells on lightweight, flexible plastic substrates is also briefly discussed to provide a perspective on one approach to achieving this enabling technology. The paper concludes with a list of issues to be addressed prior to use of thin-film solar arrays in space and the observation that with their unique characteristics, very lightweight arrays using efficient, thin-film cells on flexible substrates may become the best array option for a subset of Earth orbiting missions.

  6. Dust Accumulation and Cleaning of the MER Opportunity Solar Array

    NASA Astrophysics Data System (ADS)

    Herman, J.

    2015-12-01

    The solar array of the NASA Mars Exploration Rover (MER) Opportunity was expected to accumulate a sufficient quantity of dust after ninety Martian days (sols) such that it could no longer provide enough energy to guarantee continued surface operations. Instead, due in part to low dust accumulation rates and numerous dust cleaning events, Opportunity continues to operate on the Martian surface for over 4000 sols (over six Mars years). During this time period, the rover experienced six Martian winters and several dust storms. Because the sources of solar energy loss are known, the solar array energy output offers a method to scientifically estimate the loading and aeolian removal of dust from the solar array each sol. We will discuss the accumulation of dust on the solar panels as a proxy for dust movement at Meridiani Planum over the course of the entire mission to date.

  7. Dust Accumulation and Cleaning of the MER Spirit Solar Array

    NASA Astrophysics Data System (ADS)

    Herman, J. A.; Lemmon, M. T.; Johnson, J. R.; Cantor, B. A.; Stella, P. M.; Chin, K. B.; Wood, E. G.

    2012-12-01

    The solar array of the NASA Mars Exploration Rover (MER) Spirit was expected to accumulate so much dust after ninety Martian days (sols) that it could no longer provide enough energy to guarantee continued surface operations. Instead, due in part to low dust accumulation rates and numerous dust cleaning events, Spirit carried out surface operations for over 2200 sols (over three Mars years). During this time period, the rover experienced four Martian winters and several dust storms. Because the sources of solar energy loss are known, the solar array energy output offers a tool to quantitatively estimate the loading and aeolian removal of dust from the solar array each sol. We will discuss the accumulation of dust on the solar panels as a proxy for dust movement at Gusev Crater over the course of the entire mission.

  8. Dust Accumulation and Cleaning of the MER Solar Arrays

    NASA Astrophysics Data System (ADS)

    Herman, J. A.; Lemmon, M. T.; Stella, P.; Chin, K. B.; Wood, E. G.

    2010-12-01

    The solar arrays of the two NASA Mars Exploration Rovers (MER), Spirit and Opportunity, were expected to accumulate so much dust after 90 Martian days (sols) that they could no longer provide enough energy to guarantee continued surface operations. Instead, due in part to low dust accumulation rates and numerous dust cleaning events, they have carried out surface operations for over 2200 sols each. During this time period, the rovers experienced four Martian winters and several dust storms. Because the sources of solar energy loss are known, the solar array energy output offers a tool to scientifically estimate the loading and aeolian removal of dust from the solar arrays each sol. We will discuss the accumulation of dust on the solar panels as a proxy for dust movement on the Martian surface over the last 6 years.

  9. Advances in solar radio astronomy

    NASA Technical Reports Server (NTRS)

    Kundu, M. R.

    1982-01-01

    The status of the observations and interpretations of the sun's radio emission covering the entire radio spectrum from millimeter wavelengths to hectometer and kilometer wavelengths is reviewed. Emphasis is given to the progress made in solar radio physics as a result of recent advances in plasma and radiation theory. It is noted that the capability now exists of observing the sun with a spatial resolution of approximately a second of arc and a temporal resolution of about a millisecond at centimeter wavelengths and of obtaining fast multifrequency two-dimensional pictures of the sun at meter and decameter wavelengths. A summary is given of the properties of nonflaring active regions at millimeter, centimeter, and meter-decameter wavelengths. The properties of centimeter wave bursts are discussed in connection with the high spatial resolution observations. The observations of the preflare build-up of an active region are reviewed. High spatial resolution observations (a few seconds of arc to approximately 1 arcsec) are discussed, with particular attention given to the one- and two-dimensional maps of centimeter-wavelength burst sources.

  10. Arrays of ultrathin silicon solar microcells

    SciTech Connect

    Rogers, John A.; Rockett, Angus A.; Nuzzo, Ralph; Yoon, Jongseung; Baca, Alfred

    2015-08-11

    Provided are solar cells, photovoltaics and related methods for making solar cells, wherein the solar cell is made of ultrathin solar grade or low quality silicon. In an aspect, the invention is a method of making a solar cell by providing a solar cell substrate having a receiving surface and assembling a printable semiconductor element on the receiving surface of the substrate via contact printing. The semiconductor element has a thickness that is less than or equal to 100 .mu.m and, for example, is made from low grade Si.

  11. Arrays of ultrathin silicon solar microcells

    DOEpatents

    Rogers, John A; Rockett, Angus A; Nuzzo, Ralph; Yoon, Jongseung; Baca, Alfred

    2014-03-25

    Provided are solar cells, photovoltaics and related methods for making solar cells, wherein the solar cell is made of ultrathin solar grade or low quality silicon. In an aspect, the invention is a method of making a solar cell by providing a solar cell substrate having a receiving surface and assembling a printable semiconductor element on the receiving surface of the substrate via contact printing. The semiconductor element has a thickness that is less than or equal to 100 .mu.m and, for example, is made from low grade Si.

  12. Laboratory 15 kV high voltage solar array facility

    NASA Technical Reports Server (NTRS)

    Kolecki, J. C.; Gooder, S. T.

    1976-01-01

    The laboratory high voltage solar array facility is a photoelectric power generating system. Consisting of nine modules with over 23,000 solar cells, the facility is capable of delivering more than a kilowatt of power. The physical and electrical characteristics of the facility are described.

  13. Space Station Freedom solar array panels plasma interaction test facility

    NASA Technical Reports Server (NTRS)

    Martin, Donald F.; Mellott, Kenneth D.

    1989-01-01

    The Space Station Freedom Power System will make extensive use of photovoltaic (PV) power generation. The phase 1 power system consists of two PV power modules each capable of delivering 37.5 KW of conditioned power to the user. Each PV module consists of two solar arrays. Each solar array is made up of two solar blankets. Each solar blanket contains 82 PV panels. The PV power modules provide a 160 V nominal operating voltage. Previous research has shown that there are electrical interactions between a plasma environment and a photovoltaic power source. The interactions take two forms: parasitic current loss (occurs when the currect produced by the PV panel leaves at a high potential point and travels through the plasma to a lower potential point, effectively shorting that portion of the PV panel); and arcing (occurs when the PV panel electrically discharges into the plasma). The PV solar array panel plasma interaction test was conceived to evaluate the effects of these interactions on the Space Station Freedom type PV panels as well as to conduct further research. The test article consists of two active solar array panels in series. Each panel consists of two hundred 8 cm x 8 cm silicon solar cells. The test requirements dictated specifications in the following areas: plasma environment/plasma sheath; outgassing; thermal requirements; solar simulation; and data collection requirements.

  14. Advanced X-Ray Timing Array (AXTAR) Animation

    NASA Technical Reports Server (NTRS)

    Hopkins, Randall C.; Thompson, Kevin S.

    2011-01-01

    The animation depicts NASA's concept for a next-generation Advanced X-ray Timing Mission. The models and their textures doe not necessarily represent the final iteration. Delivery specifications include launch with Taurus II or Falcon 9, mass of 2650 kg, with a circular low earth orbit at approximately 600 km. The inclination depends on the launch vehicle and spacecraft mass. AXTAR's prime instrument will probe the physics of neutron stars and black holes through X-ray timing and spectral measurements. The primary instrument will be the Large Area Timing Array (LATA). The Sky Monitor Clusters configuration consists of 27 Sky Monitor cameras th at are grouped in five clusters. This configuration will achieve approximately 85 percent all sky coverage. Spacecraft components include a science bus to house the LATA of supermodules; a spacecraft bus to house components such as propulsion tanks, avionics, and reaction wheels; solar arrays configured from space-qualified GaAs 3-junction cells; star trackers for attitude knowledge; a propulsion system of four pods, each containing one 100 lbf and two 5 lbf engines; a launch vehicle adaptor; and a radiation shield.

  15. Low-Concentration-Ratio Solar-Cell Arrays

    NASA Technical Reports Server (NTRS)

    Biss, M. S.; Reed, David A., Jr.

    1986-01-01

    Paper presents design concept for mass-producible arrays of solar electric batteries and concentrators tailored to individual requirements. Arrays intended primarily for space stations needing about 100 kW of power. However, modular, lightweight, compact, and relatively low-cost design also fulfill requirements of some terrestrial applications. Arrays built with currently available materials. Pultrusions, injectionmolded parts, and composite materials used extensively to keep weight low. For added flexibility in design and construction, silicon and gallium arsenide solar-cell panels interchangeable.

  16. Modeling and Flight Data Analysis of Spacecraft Dynamics with a Large Solar Array Paddle

    NASA Technical Reports Server (NTRS)

    Iwata, Takanori; Maeda, Ken; Hoshino, Hiroki

    2007-01-01

    The Advanced Land Observing Satellite (ALOS) was launched on January 24 2006 and has been operated successfully since then. This satellite has the attitude dynamics characterized by three large flexible structures, four large moving components, and stringent attitude/pointing stability requirements. In particular, it has one of the largest solar array paddles. Presented in this paper are flight data analyses and modeling of spacecraft attitude motion induced by the large solar array paddle. On orbit attitude dynamics was first characterized and summarized. These characteristic motions associated with the solar array paddle were identified and assessed. These motions are thermally induced motion, the pitch excitation by the paddle drive, and the role excitation. The thermally induced motion and the pitch excitation by the paddle drive were modeled and simulated to verify the mechanics of the motions. The control law updates implemented to mitigate the attitude vibrations are also reported.

  17. Photographic films for the Multi-Spectral Solar Telescope Array

    NASA Technical Reports Server (NTRS)

    Hoover, Richard B.; Walker, Arthur B. C., Jr.; Deforest, Craig E.; Allen, Maxwell J.; Lindblom, Joakim F.; Gilliam, Lou; November, Larry; Brown, Todd; Dewan, Clyde A.

    1992-01-01

    The rocketborne Multi-Spectral Solar Telescope Array (MSSTA) uses an array of Ritchey-Chretien, Cassegrain, and Herschelian telescopes to produce ultrahigh-resolution full-disk images of the sun within the soft X-ray, EUV, and FUV ranges. Such imaging of the solar disk and corona out to several solar radii placed great demands on the MSSTA's data storage capabilities; in addition, its photographic films required very low outgassing rates. Results are presented from calibration tests conducted on the MSSTA's emulsions, based on measurements at NIST's synchrotron facility.

  18. Solar Array and Auroral Charging Studies of DMSP Spacecraft

    NASA Technical Reports Server (NTRS)

    Matias, Kelwin

    2013-01-01

    The SSJ electrostatic analyzers and the SSIES plasma instruments on the DMSP spacecraft in low Earth polar orbit can be used to conduct case studies of auroral and solar array charging. We will use a program written in the Interactive Data Language (IDL) to evaluate questionable charging events in the SSJ records by comparing charging signatures in SSJ and SSIES data. In addition, we will assemble a number of case studies of solar array charging showing the signatures from the SSJ data and compare to the SSIES charging signatures. In addition we will use Satellite Tool Kit (STK) to propagate orbits, obtain solar intensity, and use to verify onset of charging with sunrise.

  19. Integrated Solar-Panel Antenna Array for CubeSats

    NASA Technical Reports Server (NTRS)

    Baktur, Reyhan

    2016-01-01

    The goal of the Integrated Solar-Panel Antenna Array for CubeSats (ISAAC) project is to design and demonstrate an effective and efficien toptically transparent, high-gain, lightweight, conformal X-band antenna array that is integrated with the solar panels of a CubeSat. The targeted demonstration is for a Near Earth Network (NEN)radio at X-band, but the design can be easilyscaled to other network radios for higher frequencies. ISAAC is a less expensive and more flexible design for communication systemscompared to a deployed dish antenna or the existing integrated solar panel antenna design.

  20. Quality assessment of solar UV irradiance measured with array spectroradiometers

    NASA Astrophysics Data System (ADS)

    Egli, L.; Gröbner, J.; Hülsen, G.; Bachmann, L.; Blumthaler, M.; Dubard, J.; Khazova, M.; Kift, R.; Hoogendijk, K.; Serrano, A.; Smedley, A. R. D.; Vilaplana, J.-M.

    2015-12-01

    The reliable quantification of ultraviolet (UV) radiation at the Earth's surface requires accurate measurements of spectral global solar UV irradiance in order to determine the UV exposure to human skin and to understand long-term trends in this parameter. Array spectroradiometers are small, light, robust and cost effective instruments and are increasingly used for spectral irradiance measurements. Within the European EMRP-ENV03 project "Solar UV", new devices, guidelines, and characterization methods have been developed to improve solar UV measurements with array spectroradiometers and support to the end-user community has been provided. In order to assess the quality of 14 end-user array spectroradiometers, a solar UV intercomparison was held on the measurement platform of the World Radiation Center (PMOD/WRC) in Davos, Switzerland, from 10 to 17 July 2014. The results of the intercomparison revealed that array spectroradiometers, currently used for solar UV measurements, show a large variation in the quality of their solar UV measurements. Most of the instruments overestimate the erythema weighted UV index - in particular at low solar zenith angles - due to stray light contribution in the UV-B range. The spectral analysis of global solar UV irradiance further supported the finding that the uncertainties in the UV-B range are very large due to stray light contribution in this wavelength range. In summary, the UV index may be detected by some commercially available array spectroradiometer within 5 % compared to the world reference spectroradiometer, if well characterized and calibrated, but only for a limited range or solar zenith angle. Generally, the tested instruments are not yet suitable for solar UV measurements for the entire range between 290 to 400 nm under all atmospheric conditions.

  1. Advanced solar energy conversion. [solar pumped gas lasers

    NASA Technical Reports Server (NTRS)

    Lee, J. H.

    1981-01-01

    An atomic iodine laser, a candidate for the direct solar pumped lasers, was successfully excited with a 4 kW beam from a xenon arc solar simulator, thus proving the feasibility of the concept. The experimental set up and the laser output as functions of operating conditions are presented. The preliminary results of the iodine laser amplifier pumped with the HCP array to which a Q switch for giant pulse production was coupled are included. Two invention disclosures - a laser driven magnetohydrodynamic generator for conversion of laser energy to electricity and solar pumped gas lasers - are also included.

  2. JPL Large Advanced Antenna Station Array Study

    NASA Technical Reports Server (NTRS)

    1978-01-01

    In accordance with study requirements, two antennas are described: a 30 meter standard antenna and a 34 meter modified antenna, along with a candidate array configuration for each. Modified antenna trade analyses are summarized, risks analyzed, costs presented, and a final antenna array configuration recommendation made.

  3. Space Station Freedom solar array containment box mechanisms

    NASA Astrophysics Data System (ADS)

    Johnson, Mark E.; Haugen, Bert; Anderson, Grant

    1994-05-01

    Space Station Freedom will feature six large solar arrays, called solar array wings, built by Lockheed Missiles & Space Company under contract to Rockwell International, Rocketdyne Division. Solar cells are mounted on flexible substrate panels which are hinged together to form a 'blanket.' Each wing is comprised of two blankets supported by a central mast, producing approximately 32 kW of power at beginning-of-life. During launch, the blankets are fan-folded and compressed to 1.5 percent of their deployed length into containment boxes. This paper describes the main containment box mechanisms designed to protect, deploy, and retract the solar array blankets: the latch, blanket restraint, tension, and guidewire mechanisms.

  4. Interconnnect and bonding technologies for large flexible solar arrays

    NASA Technical Reports Server (NTRS)

    1976-01-01

    Thermocompression bonding and conductive adhesive bonding are developed and evaluated as alternate methods of joining solar cells to their interconnect assemblies. Bonding materials and process controls applicable to fabrication of large, flexible substrate solar cell arrays are studied. The primary potential use of the techniques developed is on the solar array developed by NASA/MSFC and LMSC for solar electric propulsion (SEP) and shuttle payload applications. This array is made up of flexible panels approximately 0.7 by 3.4 meters. It is required to operate in space between 0.3 and 6 AU for 5 years with limited degradation. Materials selected must be capable of enduring this space environment, including outgassing and radiation.

  5. Space Station Freedom solar array containment box mechanisms

    NASA Technical Reports Server (NTRS)

    Johnson, Mark E.; Haugen, Bert; Anderson, Grant

    1994-01-01

    Space Station Freedom will feature six large solar arrays, called solar array wings, built by Lockheed Missiles & Space Company under contract to Rockwell International, Rocketdyne Division. Solar cells are mounted on flexible substrate panels which are hinged together to form a 'blanket.' Each wing is comprised of two blankets supported by a central mast, producing approximately 32 kW of power at beginning-of-life. During launch, the blankets are fan-folded and compressed to 1.5 percent of their deployed length into containment boxes. This paper describes the main containment box mechanisms designed to protect, deploy, and retract the solar array blankets: the latch, blanket restraint, tension, and guidewire mechanisms.

  6. Planetary and deep space requirements for photovoltaic solar arrays

    NASA Astrophysics Data System (ADS)

    Bankston, C. P.; Bennett, R. B.; Stella, P. M.

    1995-10-01

    In the past 25 years, the majority of interplanetary spacecraft have been powered by nuclear sources. However, as the emphasis on smaller, low cost missions gains momentum, the majority of missions now being planned will use photovoltaic solar arrays. This will present challenges to the solar array builders, inasmuch as planetary requirements usually differ from earth orbital requirements. In addition, these requirements often differ greatly, depending on the specific mission; for example, inner planets vs. outer planets, orbiters vs. flybys, spacecraft vs. landers, and so on. Also, the likelihood of electric propulsion missions will influence the requirements placed on solar array developers. The paper will discuss representative requirements for a range of planetary missions now in the planning stages. Insofar as inner planets are concerned, a Mercury orbiter is being studied with many special requirements. Solar arrays would be exposed to high temperatures and a potentially high radiation environment, and will need to be increasingly pointed off sun as the vehicle approaches Mercury. Identification and development of cell materials and arrays at high incidence angles will be critical to the design. Missions to the outer solar system that have been studied include a Galilean orbiter and a flight to the Kuiper belt. While onboard power requirements would be small (as low as 10 watts), the solar intensity will require relatively large array areas. As a result, such missions will demand extremely compact packaging and low mass structures to conform to launch vehicle constraints. In turn, the large are, low mass designs will impact allowable spacecraft loads. Inflatable array structures, with and without concentration, and multiband gap cells will be considered if available. In general, the highest efficiency cell technologies operable under low intensity, low temperature conditions are needed. Solar arrays will power missions requiring as little as approximately 100

  7. Planetary and deep space requirements for photovoltaic solar arrays

    NASA Technical Reports Server (NTRS)

    Bankston, C. P.; Bennett, R. B.; Stella, P. M.

    1995-01-01

    In the past 25 years, the majority of interplanetary spacecraft have been powered by nuclear sources. However, as the emphasis on smaller, low cost missions gains momentum, the majority of missions now being planned will use photovoltaic solar arrays. This will present challenges to the solar array builders, inasmuch as planetary requirements usually differ from earth orbital requirements. In addition, these requirements often differ greatly, depending on the specific mission; for example, inner planets vs. outer planets, orbiters vs. flybys, spacecraft vs. landers, and so on. Also, the likelihood of electric propulsion missions will influence the requirements placed on solar array developers. The paper will discuss representative requirements for a range of planetary missions now in the planning stages. Insofar as inner planets are concerned, a Mercury orbiter is being studied with many special requirements. Solar arrays would be exposed to high temperatures and a potentially high radiation environment, and will need to be increasingly pointed off sun as the vehicle approaches Mercury. Identification and development of cell materials and arrays at high incidence angles will be critical to the design. Missions to the outer solar system that have been studied include a Galilean orbiter and a flight to the Kuiper belt. While onboard power requirements would be small (as low as 10 watts), the solar intensity will require relatively large array areas. As a result, such missions will demand extremely compact packaging and low mass structures to conform to launch vehicle constraints. In turn, the large are, low mass designs will impact allowable spacecraft loads. Inflatable array structures, with and without concentration, and multiband gap cells will be considered if available. In general, the highest efficiency cell technologies operable under low intensity, low temperature conditions are needed. Solar arrays will power missions requiring as little as approximately 100

  8. Material considerations in the STEREO solar array design

    NASA Astrophysics Data System (ADS)

    Tanzman, Jennifer R.

    2008-12-01

    Solar TErrestrial RElations Observatory (STEREO), the third mission in NASA's Solar Terrestrial Probes program, launched aboard a single Delta II 7925 launch vehicle on October 25, 2006 from Cape Canaveral. This two-year mission employs two nearly-identical, space-based observatories, one ahead of the Earth in its orbit, and the other trailing behind, to provide the first stereoscopic measurements of the sun and its coronal mass ejections, or CMEs. The STEREO observatories utilize four sets of solar arrays, each of which experienced a two-stage deployment on-orbit. This paper illustrates material considerations in the solar array subsystem design. It first focuses on the solar array substrate, considering material coefficient of thermal expansion (CTE) concerns when choosing a substrate laminate to which the solar cells will adhere. It then explores a similar issue when choosing a substrate insert material. Next, the focus shifts to material considerations in the solar array hinge design. This design was driven not just by function, but by a host of different material considerations, ranging from mass savings to fabrication time and cost.

  9. Feasibility study of a 110 watt per kilogram lightweight solar array system

    NASA Technical Reports Server (NTRS)

    Shepard, N. F.; Stahle, C. V.; Schneider, A.; Hanson, K. L.

    1972-01-01

    An investigation of the feasibility of a solar array panel subsystem which will produce 10,000 watts of electrical output at 1 A.U. with an overall beginning-of-life power-to-weight ratio of at least 110 watt/kg is reported. A description of the current baseline configuration which meets these requirements is presented. A parametric analysis of the single boom, two blanket planar solar array system was performed to arrive at the optimum system aspect ratio. A novel concept for the stiffening of a lightweight solar array by canting the solar cell blankets at a small angle to take advantage of the inherent in-plane stiffness to increase the symmetric out-of-plane frequency is introduced along with a preliminary analysis of the stiffening effect. A comparison of welded and soldered solar cell interconnections leads to the conclusion that welding is required on this ultralightweight solar array. The use of a boron/aluminum composite material in a BI-STEM type deployable boom is investigated as a possible advancement in the state-of-the-art.

  10. Solar radiation on Mars: Stationary photovoltaic array

    NASA Technical Reports Server (NTRS)

    Appelbaum, J.; Sherman, I.; Landis, G. A.

    1993-01-01

    Solar energy is likely to be an important power source for surface-based operation on Mars. Photovoltaic cells offer many advantages. In this article we have presented analytical expressions and solar radiation data for stationary flat surfaces (horizontal and inclined) as a function of latitude, season and atmospheric dust load (optical depth). The diffuse component of the solar radiation on Mars can be significant, thus greatly affecting the optimal inclination angle of the photovoltaic surface.

  11. Thermal Cycling of Mir Cooperative Solar Array (MCSA) Test Panels

    NASA Technical Reports Server (NTRS)

    Hoffman, David J.; Scheiman, David A.

    1997-01-01

    The Mir Cooperative Solar Array (MCSA) project was a joint US/Russian effort to build a photovoltaic (PV) solar array and deliver it to the Russian space station Mir. The MCSA is currently being used to increase the electrical power on Mir and provide PV array performance data in support of Phase 1 of the International Space Station (ISS), which will use arrays based on the same solar cells used in the MCSA. The US supplied the photovoltaic power modules (PPMs) and provided technical and programmatic oversight while Russia provided the array support structures and deployment mechanism and built and tested the array. In order to ensure that there would be no problems with the interface between US and Russian hardware, an accelerated thermal life cycle test was performed at NASA Lewis Research Center on two representative samples of the MCSA. Over an eight-month period (August 1994 - March 1995), two 15-cell MCSA solar array 'mini' panel test articles were simultaneously put through 24,000 thermal cycles (+80 C to -100 C), equivalent to four years on-orbit. The test objectives, facility, procedure and results are described in this paper. Post-test inspection and evaluation revealed no significant degradation in the structural integrity of the test articles and no electrical degradation, not including one cell damaged early as an artifact of the test and removed from consideration. The interesting nature of the performance degradation caused by this one cell, which only occurred at elevated temperatures, is discussed. As a result of this test, changes were made to improve some aspects of the solar cell coupon-to-support frame interface on the flight unit. It was concluded from the results that the integration of the US solar cell modules with the Russian support structure would be able to withstand at least 24,000 thermal cycles (4 years on-orbit).

  12. Tucson Public Building Solar Arrays Final Report

    SciTech Connect

    Bruce Plenk

    2002-12-17

    The City of Tucson installed photovoltaic panels on parking structures at a library/police substation and developed a county-wide solar education program based in the public library system, including numerous new solar resources for the libraries and training for library staff.

  13. Radiation degradation of solar cell arrays

    NASA Technical Reports Server (NTRS)

    Hill, C. W.

    1975-01-01

    A method of incorporating a detailed solar cell radiation degradation model into a convenient computational scheme suitable for the solar electric propulsion system is outlined. The study shows that several existing codes may be applied in sequence to solve the problem.

  14. Thin solar cell and lightweight array

    NASA Technical Reports Server (NTRS)

    Brandhorst, Henry W., Jr. (Inventor); Weinberg, Irving (Inventor)

    1991-01-01

    A thin, lightweight solar cell that utilizes front contact metallization is presented. Both the front light receiving surface of the solar cell and the facing surface of the cover glass are recessed to accommodate this metallization. This enables the two surfaces to meet flush for an optimum seal.

  15. Hydraulic performance of a multistage array of advanced centrifugal contactors

    SciTech Connect

    Hodges, M.E.

    1984-01-01

    The hydraulic characteristics of an advanced design centrifugal contactor array have been determined at the Savannah River Laboratory (SRL). The advanced design utilizes couette mixing (Taylor vortices) in the annulus between the rotating and stationary bowls. Excellent phase separation over a wide range of flow conditions was obtained. Interfaces within an entire eight-stage array were controlled with a single weir air pressure. 2 references, 5 figures.

  16. Telescoping Solar Array Concept for Achieving High Packaging Efficiency

    NASA Technical Reports Server (NTRS)

    Mikulas, Martin; Pappa, Richard; Warren, Jay; Rose, Geoff

    2015-01-01

    Lightweight, high-efficiency solar arrays are required for future deep space missions using high-power Solar Electric Propulsion (SEP). Structural performance metrics for state-of-the art 30-50 kW flexible blanket arrays recently demonstrated in ground tests are approximately 40 kW/cu m packaging efficiency, 150 W/kg specific power, 0.1 Hz deployed stiffness, and 0.2 g deployed strength. Much larger arrays with up to a megawatt or more of power and improved packaging and specific power are of interest to mission planners for minimizing launch and life cycle costs of Mars exploration. A new concept referred to as the Compact Telescoping Array (CTA) with 60 kW/cu m packaging efficiency at 1 MW of power is described herein. Performance metrics as a function of array size and corresponding power level are derived analytically and validated by finite element analysis. Feasible CTA packaging and deployment approaches are also described. The CTA was developed, in part, to serve as a NASA reference solar array concept against which other proposed designs of 50-1000 kW arrays for future high-power SEP missions could be compared.

  17. Summary of flat-plate solar array project documentation. Abstracts of published documents, 1975 to June 1982

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Technologies that will enable the private sector to manufacture and widely use photovoltaic systems for the generation of electricity in residential, commercial, industrial, and government applications at a cost per watt that is competitive with other means is investigated. Silicon refinement processes, advanced silicon sheet growth techniques, solar cell development, encapsulation, automated fabrication process technology, advanced module/array design, and module/array test and evaluation techniques are developed.

  18. Solar array flight experiment/dynamic augmentation experiment

    NASA Technical Reports Server (NTRS)

    Young, Leighton E.; Pack, Homer C., Jr.

    1987-01-01

    This report presents the objectives, design, testing, and data analyses of the Solar Array Flight Experiment/Dynamic Augmentation Experiment (SAFE/DAE) that was tested aboard Shuttle in September 1984. The SAFE was a lightweight, flat-fold array that employed a thin polyimide film (Kapton) as a substrate for the solar cells. Extension/retraction, dynamics, electrical and thermal tests, were performed. Of particular interest is the dynamic behavior of such a large lightweight structure in space. Three techniques for measuring and analyzing this behavior were employed. The methodology for performing these tests, gathering data, and data analyses are presented. The report shows that the SAFE solar array technology is ready for application and that new methods are available to assess the dynamics of large structures in space.

  19. Wire Array Solar Cells: Fabrication and Photoelectrochemical Studies

    NASA Astrophysics Data System (ADS)

    Spurgeon, Joshua Michael

    Despite demand for clean energy to reduce our addiction to fossil fuels, the price of these technologies relative to oil and coal has prevented their widespread implementation. Solar energy has enormous potential as a carbon-free resource but is several times the cost of coal-produced electricity, largely because photovoltaics of practical efficiency require high-quality, pure semiconductor materials. To produce current in a planar junction solar cell, an electron or hole generated deep within the material must travel all the way to the junction without recombining. Radial junction, wire array solar cells, however, have the potential to decouple the directions of light absorption and charge-carrier collection so that a semiconductor with a minority-carrier diffusion length shorter than its absorption depth (i.e., a lower quality, potentially cheaper material) can effectively produce current. The axial dimension of the wires is long enough for sufficient optical absorption while the charge-carriers are collected along the shorter radial dimension in a massively parallel array. This thesis explores the wire array solar cell design by developing potentially low-cost fabrication methods and investigating the energy-conversion properties of the arrays in photoelectrochemical cells. The concept was initially investigated with Cd(Se, Te) rod arrays; however, Si was the primary focus of wire array research because its semiconductor properties make low-quality Si an ideal candidate for improvement in a radial geometry. Fabrication routes for Si wire arrays were explored, including the vapor-liquid-solid growth of wires using SiCl4. Uniform, vertically aligned Si wires were demonstrated in a process that permits control of the wire radius, length, and spacing. A technique was developed to transfer these wire arrays into a low-cost, flexible polymer film, and grow multiple subsequent arrays using a single Si(111) substrate. Photoelectrochemical measurements on Si wire array

  20. Voltage-current-power meter for photovoltaic solar arrays

    NASA Technical Reports Server (NTRS)

    Ross, Ronald G. (Inventor)

    1979-01-01

    A meter is disclosed for measuring the voltage, current, and power (VIP) parameters of a photovoltaic solar array, or array module, under sunlight operating conditions utilizing a variable load connected across the array and controlled by a voltage regulator which responds to the difference between the output voltage of the array and a programmed test voltage from a source which generates a single ramp voltage for measuring and recording current as a function of voltage, repeated ramp voltages at a high rate for peak output measurements or a DC voltage for VIP measurements at selected points on the I-V characteristic curve of the array. The voltage signal from a current sensing element, such as a shunt resistor in series with the variable load, is compared with the output current of a reference solar cell to provide a normalizing signal to be added to the signal from the current-sensing element in order to provide a record of array current as a function of array voltage, i.e., for all load conditions from short circuit to open circuit. As the normalized current is thus measured, an analog multiplier multiplies the array voltage and normalized current to provide a measurement of power. Switches are provided to selectively connect the power, P, current, I, or voltage, V, to a meter, directly or through a peak detector. At the same time any one of the parameters V, I and P may be recorded as a function of any other parameter.

  1. Solar array electrical performance assessment for Space Station Freedom

    NASA Technical Reports Server (NTRS)

    Smith, Bryan K.; Brisco, Holly

    1993-01-01

    Electrical power for Space Station Freedom will be generated by large photovoltaic arrays with a beginning of life power requirement of 30.8 kW per array. The solar arrays will operate in a Low Earth Orbit (LEO) over a design life of fifteen years. This paper provides an analysis of the predicted solar array electrical performance over the design life and presents a summary of supporting analysis and test data for the assigned model parameters and performance loss factors. Each model parameter and loss factor is assessed based upon program requirements, component analysis and test data to date. A description of the LMSC performance model future test plans and predicted performance ranges are also given.

  2. Solar array electrical performance assessment for Space Station Freedom

    NASA Technical Reports Server (NTRS)

    Smith, Bryan K.; Brisco, Holly

    1993-01-01

    Electrical power for Space Station Freedom will be generated by large Photovoltaic arrays with a beginning of life power requirement of 30.8 kW per array. The solar arrays will operate in a Low Earth Orbit (LEO) over a design life of fifteen years. This paper provides an analysis of the predicted solar array electrical performance over the design life and presents a summary of supporting analysis and test data for the assigned model parameters and performance loss factors. Each model parameter and loss factor is assessed based upon program requirements, component analysis, and test data to date. A description of the LMSC performance model, future test plans, and predicted performance ranges are also given.

  3. ACTS Battery and Solar Array Assembly On-Orbit Measured Performance

    NASA Technical Reports Server (NTRS)

    Hilderman, Don R.

    2005-01-01

    The Advanced Communications Technology Satellite (ACTS) is a NASA experimental communications satellite system designed to demonstrate on-orbit Ka-band communications and switching technologies that will be used by NASA and the commercial sector in the 21st century. The ACTS was launched on September 12, 1993, and has performed over 10 years of successful experimental operations. The purpose of this report is to describe the ACTS power subsystem and the ACTS solar array and battery assemblies located within the power subsystem and then to document on-orbit measured performance from launch to mission end on April 28, 2004. Solar array and battery performance data is presented, and respective conclusions are drawn. The total solar array power available to the spacecraft was measured each year at the same time, and battery voltage performance was measured twice per year at the same times during peak solar eclipse. At the highest spacecraft power demand, the ACTS uses approximately 1113 W of electrical power during the low-burstrate experiment to operate all six satellite subsystems. After 10 years of on-orbit operation, solar array available output power normal to the Sun measured 1508 W, which represents 395 W of excess margin. The ACTS batteries have successfully supported the ACTS experiment program for over 10 years and operated in excess of 900 charge and discharge cycles through 21 eclipse seasons.

  4. Solar cell array design handbook, volume 1

    NASA Technical Reports Server (NTRS)

    Rauschenbach, H. S.

    1976-01-01

    Twelve chapters discuss the following: historical developments, the environment and its effects, solar cells, solar cell filters and covers, solar cell and other electrical interconnections, blocking and shunt diodes, substrates and deployment mechanisms, material properties, design synthesis and optimization, design analysis, procurement, production and cost aspects, evaluation and test, orbital performance, and illustrative design examples. A comprehensive index permits rapid locating of desired topics. The handbook consists of two volumes: Volume 1 is of an expository nature while Volume 2 contains detailed design data in an appendix-like fashion. Volume 2 includes solar cell performance data, applicable unit conversion factors and physical constants, and mechanical, electrical, thermal optical, magnetic, and outgassing material properties. Extensive references are provided.

  5. High voltage solar cell power generating system for regulated solar array development

    NASA Technical Reports Server (NTRS)

    Levy, E., Jr.; Hoffman, A. C.

    1973-01-01

    A laboratory solar power system regulated by on-panel switches has been delivered for operating high power (3 kw), high voltage (15,000 volt) loads (communication tubes, ion thrusters). The modular system consists of 26 solar arrays, each with an integral light source and cooling system. A typical array contains 2560 series-connected cells. Each light source consists of twenty 500 watt tungsten iodide lamps providing plus or minus 5 per cent uniformity at one solar constant. An array temperature of less than 40 C is achieved using an infrared filter, a water cooled plate, a vacuum hold-down system, and air flushing.

  6. Experimental Study of Arcing on High-voltage Solar Arrays

    NASA Technical Reports Server (NTRS)

    Vayner, Boris; Galofaro, Joel; Ferguson, Dale

    2005-01-01

    The main obstacle to the implementation of a high-voltage solar array in space is arcing on the conductor-dielectric junctions exposed to the surrounding plasma. One obvious solution to this problem would be the installation of fully encapsulated solar arrays which were not having exposed conductors at all. However, there are many technological difficulties that must be overcome before the employment of fully encapsulated arrays will turn into reality. An alternative solution to raise arc threshold by modifications of conventionally designed solar arrays looks more appealing, at least in the nearest future. A comprehensive study of arc inception mechanism [1-4] suggests that such modifications can be done in the following directions: i) to insulate conductor-dielectric junction from a plasma environment (wrapthrough interconnects); ii) to change a coverglass geometry (overhang); iii) to increase a coverglass thickness; iiii) to outgas areas of conductor-dielectric junctions. The operation of high-voltage array in LEO produces also the parasitic current power drain on the electrical system. Moreover, the current collected from space plasma by solar arrays determines the spacecraft floating potential that is very important for the design of spacecraft and its scientific apparatus. In order to verify the validity of suggested modifications and to measure current collection five different solar array samples have been tested in large vacuum chamber. Each sample (36 silicon based cells) consists of three strings containing 12 cells connected in series. Thus, arc rate and current collection can be measured on every string independently, or on a whole sample when strings are connected in parallel. The heater installed in the chamber provides the possibility to test samples under temperature as high as 80 C that simulates the LEO operational temperature. The experimental setup is described below.

  7. Experimental Study of Arcing on High-Voltage Solar Arrays

    NASA Technical Reports Server (NTRS)

    Vayner, Boris; Galofaro, Joel; Ferguson, Dale

    2003-01-01

    The main obstacle to the implementation of a high-voltage solar array in space is arcing on the conductor-dielectric junctions exposed to the surrounding plasma. One obvious solution to this problem would be the installation of fully encapsulated solar arrays which were not having exposed conductors at all. However, there are many technological difficulties that must be overcome before the employment of fully encapsulated arrays will turn into reality. An alternative solution to raise arc threshold by modifications of conventionally designed solar arrays looks more appealing, at least in the nearest future. A comprehensive study of arc inception mechanism suggests that such modifications can be done in the following directions: 1) To insulate conductor-dielectric junction from a plasma environment (wrapthrough interconnects); 2) To change a coverglass geometry (overhang); 3) To increase a coverglass thickness; 4) To outgas areas of conductor-dielectric junctions. The operation of high-voltage array in LEO produces also the parasitic current power drain on the electrical system. Moreover, the current collected from space plasma by solar arrays determines the spacecraft floating potential that is very important for the design of spacecraft and its scientific apparatus. In order to verify the validity of suggested modifications and to measure current collection five different solar array samples have been tested in a large vacuum chamber. Each sample (36 silicon based cells) consists of three strings containing 12 cells connected in series. Thus, arc rate and current collection can be measured on every string independently, or on a whole sample when strings are connected in parallel. The heater installed in the chamber provides the possibility to test samples under temperature as high as 80 C that stimulates the LEO operational temperature. The experimental setup is described below.

  8. EarthScope's Transportable Array: Advancing Eastward

    NASA Astrophysics Data System (ADS)

    Busby, R. W.; Vernon, F.; Newman, R. L.; Astiz, L.

    2006-12-01

    EarthScope's Transportable Array has installed more than 200 high-quality broadband seismic stations over the last 3 years in the western US. These stations have a nominal spacing of 70 km and are part of an eventual 400 station array that migrates from west to east at a rate of 18 stations per month. The full 400 stations will be operating by September 2007. Stations have a residence time of about 2 years before being relocated to the next site. Throughout the continental US, 1623 sites are expected to be occupied. Standardized procedures and protocols have been developed to streamline all aspects of Transportable Array operations, from siting to site construction and installation to equipment purchasing and data archiving. Earned Value Management tools keep facility installation and operation on budget and schedule. A diverse, yet efficient, infrastructure installs and maintains the Transportable Array. Sensors, dataloggers, and other equipment are received and tested by the IRIS PASSCAL Instrument Center and shipped to regional storage facilities. To engage future geoscientists in the project, students are trained to conduct field and analytical reconnaissance to identify suitable seismic station sites. Contract personnel are used for site verification; vault construction; and installation of sensors, power, and communications systems. IRIS staff manages permitting, landowner communications, and station operations and maintenance. Seismic signal quality and metadata are quality-checked at the Array Network Facility at the University of California-San Diego and simultaneously archived at the IRIS Data Management Center in Seattle. Station equipment has been specifically designed for low power, remote, unattended operation and uses diverse two-way IP communications for real-time transmission. Digital cellular services, VSAT satellite, and commercial DSL, cable or wireless transport services are employed. Automatic monitoring of status, signal quality and

  9. Advances in Perovskite Solar Cells

    PubMed Central

    Zuo, Chuantian; Bolink, Henk J.; Han, Hongwei; Huang, Jinsong

    2016-01-01

    Organolead halide perovskite materials possess a combination of remarkable optoelectronic properties, such as steep optical absorption edge and high absorption coefficients, long charge carrier diffusion lengths and lifetimes. Taken together with the ability for low temperature preparation, also from solution, perovskite‐based devices, especially photovoltaic (PV) cells have been studied intensively, with remarkable progress in performance, over the past few years. The combination of high efficiency, low cost and additional (non‐PV) applications provides great potential for commercialization. Performance and applications of perovskite solar cells often correlate with their device structures. Many innovative device structures were developed, aiming at large‐scale fabrication, reducing fabrication cost, enhancing the power conversion efficiency and thus broadening potential future applications. This review summarizes typical structures of perovskite solar cells and comments on novel device structures. The applications of perovskite solar cells are discussed. PMID:27812475

  10. Parasitic current collection by solar arrays in LEO

    NASA Technical Reports Server (NTRS)

    Davis, Victoria A.; Gardner, Barbara M.

    1994-01-01

    Solar cells at potentials positive with respect to a surrounding plasma collect electrons. Current is collected by the exposed high voltage surfaces: the interconnects and the sides of the solar cells. This current is a drain on the array power that can be significant for high-voltage arrays. In addition, this current influences the current balance that determines the floating potential of the spacecraft. One of the objectives of the Air Force (PL/GPS) PASP Plus experiment is an improved understanding of parasitic current collection. As part of the PASP Plus program, we are using computer modeling to improve our understanding of the physical processes that control parasitic current collection.

  11. Solar Array Arcing in LEO How Much Charge is Discharged?

    NASA Technical Reports Server (NTRS)

    Ferguson, D. C.; Vayner, B. V.; Galofaro, J. T.

    2004-01-01

    It is often said that only the solar array or spacecraft surface that can be reached by an arc plume are discharged in a solar array arc in LEO (Low Earth Orbit). We present definitive results from ground test experiments done in the National Plasma Interactions (N-PI) facility at the NASA Glenn Research Center that this idea is mistaken. All structure surfaces in contact with the surrounding plasma and connected to spacecraft ground are discharged, whether the arc plasma can reach them or not. Implications from the strength and damaging effects of areas on LEO spacecraft are discussed, and mitigation techniques are proposed.

  12. Cylindrical array luminescent solar concentrators: performance boosts by geometric effects.

    PubMed

    Videira, Jose J H; Bilotti, Emiliano; Chatten, Amanda J

    2016-07-11

    This paper presents an investigation of the geometric effects within a cylindrical array luminescent solar concentrator (LSC). Photon concentration of a cylindrical LSC increases linearly with cylinder length up to 2 metres. Raytrace modelling on the shading effects of circles on their neighbours demonstrates effective incident light trapping in a cylindrical LSC array at angles of incidence between 60-70 degrees. Raytrace modelling with real-world lighting conditions shows optical efficiency boosts when the suns angle of incidence is within this angle range. On certain days, 2 separate times of peak optical efficiency can be attained over the course of sunrise-solar noon. PMID:27410904

  13. Active Control of Solar Array Dynamics During Spacecraft Maneuvers

    NASA Technical Reports Server (NTRS)

    Ross, Brant A.; Woo, Nelson; Kraft, Thomas G.; Blandino, Joseph R.

    2016-01-01

    Recent NASA mission plans require spacecraft to undergo potentially significant maneuvers (or dynamic loading events) with large solar arrays deployed. Therefore there is an increased need to understand and possibly control the nonlinear dynamics in the spacecraft system during such maneuvers. The development of a nonlinear controller is described. The utility of using a nonlinear controller to reduce forces and motion in a solar array wing during a loading event is demonstrated. The result is dramatic reductions in system forces and motion during a 10 second loading event. A motion curve derived from the simulation with the closed loop controller is used to obtain similar benefits with a simpler motion control approach.

  14. Development of an Electrostatically Clean Solar Array Panel

    NASA Technical Reports Server (NTRS)

    Stern, Theodore G.; Krumweide, Duane; Gaddy, Edward; Katz, Ira

    2000-01-01

    The results of design, analysis, and qualification of an Electrostatically Clean Solar Array (ECSA) panel are described. The objective of the ECSA design is to provide an electrostatic environment that does not interfere with sensitive instruments on scientific spacecraft. The ECSA design uses large, ITO-coated coverglasses that cover multiple solar cells, an aperture grid that covers the intercell areas, stress-relieved interconnects for connecting the aperture grid to the coverglasses, and edge clips to provides an electromagnetically shielded enclosure for the solar array active circuitry. Qualification coupons were fabricated and tested for photovoltaic response, conductivity, and survivability to launch acoustic and thermal cycling environments simulating LEO and GEO missions. The benefits of reducing solar panel interaction with the space environment are also discussed.

  15. Thin-Film Photovoltaic Solar Array Parametric Assessment

    NASA Technical Reports Server (NTRS)

    Hoffman, David J.; Kerslake, Thomas W.; Hepp, Aloysius F.; Jacobs, Mark K.; Ponnusamy, Deva

    2000-01-01

    This paper summarizes a study that had the objective to develop a model and parametrically determine the circumstances for which lightweight thin-film photovoltaic solar arrays would be more beneficial, in terms of mass and cost, than arrays using high-efficiency crystalline solar cells. Previous studies considering arrays with near-term thin-film technology for Earth orbiting applications are briefly reviewed. The present study uses a parametric approach that evaluated the performance of lightweight thin-film arrays with cell efficiencies ranging from 5 to 20 percent. The model developed for this study is described in some detail. Similar mass and cost trends for each array option were found across eight missions of various power levels in locations ranging from Venus to Jupiter. The results for one specific mission, a main belt asteroid tour, indicate that only moderate thin-film cell efficiency (approx. 12 percent) is necessary to match the mass of arrays using crystalline cells with much greater efficiency (35 percent multi-junction GaAs based and 20 percent thin-silicon). Regarding cost, a 12 percent efficient thin-film array is projected to cost about half is much as a 4-junction GaAs array. While efficiency improvements beyond 12 percent did not significantly further improve the mass and cost benefits for thin-film arrays, higher efficiency will be needed to mitigate the spacecraft-level impacts associated with large deployed array areas. A low-temperature approach to depositing thin-film cells on lightweight, flexible plastic substrates is briefly described. The paper concludes with the observation that with the characteristics assumed for this study, ultra-lightweight arrays using efficient, thin-film cells on flexible substrates may become a leading alternative for a wide variety of space missions.

  16. Mir Cooperative Solar Array Project Accelerated Life Thermal Cycling Test

    NASA Technical Reports Server (NTRS)

    Hoffman, David J.; Scheiman, David A.

    1996-01-01

    The Mir Cooperative Solar Array (MCSA) project was a joint U.S./Russian effort to build a photovoltaic (PV) solar array and deliver it to the Russian space station Mir. The MCSA will be used to increase the electrical power on Mir and provide PV array performance data in support of Phase 1 of the International Space Station. The MCSA was brought to Mir by space shuttle Atlantis in November 1995. This report describes an accelerated thermal life cycle test which was performed on two samples of the MCSA. In eight months time, two MCSA solar array 'mini' panel test articles were simultaneously put through 24,000 thermal cycles. There was no significant degradation in the structural integrity of the test articles and no electrical degradation, not including one cell damaged early and removed from consideration. The nature of the performance degradation caused by this one cell is briefly discussed. As a result of this test, changes were made to improve some aspects of the solar cell coupon-to-support frame interface on the flight unit. It was concluded from the results that the integration of the U.S. solar cell modules with the Russian support structure would be able to withstand at least 24,000 thermal cycles (4 years on-orbit). This was considered a successful development test.

  17. Design and Development of the Space Technology 5 (ST5) Solar Arrays

    NASA Technical Reports Server (NTRS)

    Lyons, John; Fatemi, Navid; Gamica, Robert; Sharma, Surya; Senft, Donna; Maybery, Clay

    2005-01-01

    The National Aeronautics and Space Administration's (NASA's) Space Technology 5 (ST5) is designed to flight-test the concept of miniaturized 'small size" satellites and innovative technologies in Earth's magnetosphere. Three satellites will map the intensity and direction of the magnetic fields within the inner magnetosphere. Due to the small area available for the solar arrays, and to meet the mission power requirements, very high-efficiency multijunction solar cells were selected to power the spacecraft built by NASA Goddard Space Flight Center (GSFC). This was done in partnership with the Air Force Research Lab (AFRL) through the Dual-Use Science and Technology (DUS&T) program. Emcore's InGaP/lnGaAs/Ge Advanced triple-junction (ATJ) solar cells, exhibiting an average air mass zero (AMO) efficiency of 28.0% (one-sun, 28 C), were used to populate the arrays. Each spacecraft employs 8 identical solar panels (total area of about 0.3 square meters), with 15 large-area solar cells per panel. The requirement for power is to support on-orbit average load of 13.5 W at 8.4 V, with plus or minus 5% off pointing. The details of the solar array design, development and qualification considerations, as well as ground electrical performance & shadowing analysis results are presented.

  18. Advanced solar concentrator: Executive summary

    NASA Technical Reports Server (NTRS)

    1981-01-01

    The preliminary design of a point-focusing solar concentrator, consisting of a steerable space frame structure supporting a paraboloidal mirror glass reflector, is described. A mass production, operation, and maintenance cost assessment is presented. A conceptual evaluation of a modified concentrator design is included. The detailed design of one of the lightweight, structurally efficient reflective elements comprising the paraboloidal reflective surface is given.

  19. Multi-100kW: Planar low cost solar array development

    NASA Technical Reports Server (NTRS)

    1984-01-01

    Seven low cost multi-100 kW planar solar array modules were fabricated and tested. Two different designs were used, demonstrating advanced solar array construction practices. Both module types utilized second generation gridded back cells featuring high efficiency and IR transparency. A silicon dioxide AR coating optimized for transmission at gamma = 1.7 microns was applied to the back surface. Two interconnect types, a single sheet printed circuit and a roll type, with alternate approaches to increasing transparency and reducing cost were designed and fabricated. Hinge stress and electrical power optimization were also examined. Two point designs were studied. The first design used a coilage longeron mast and is autonomously deployable. The second design used a Stac Beam for high natural frequency response and required astronaut assistance and assembly on orbit. It was conclusively demonstrated that planar arrays are the most cost effective design for use on the space station or other high power applications.

  20. Elastomer Encapsulant for Solar-Cell Arrays

    NASA Technical Reports Server (NTRS)

    Baum, B.; Willis, P. B.

    1985-01-01

    Butyl acrylate syrups useful potting compounds for encapsulating photovoltaic cells in modular arrays. Material pourable liquid pumped into module, then cured to rubbery consistency. Cured material is thermoset elastomer highly transparent, low cost, flexible and with good low-temperature properties.

  1. Advanced Solar Cell Testing and Characterization

    NASA Technical Reports Server (NTRS)

    Bailey, Sheila; Curtis, Henry; Piszczor, Michael

    2005-01-01

    The topic for this workshop stems from an ongoing effort by the photovoltaic community and U.S. government to address issues and recent problems associated with solar cells and arrays experienced by a number of different space systems. In April 2003, a workshop session was held at the Aerospace Space Power Workshop to discuss an effort by the Air Force to update and standardize solar cell and array qualification test procedures in an effort to ameliorate some of these problems. The organizers of that workshop session thought it was important to continue these discussions and present this information to the entire photovoltaic community. Thus, it was decided to include this topic as a workshop at the following SPRAT conference.

  2. Integrated Antenna/Solar Array Cell (IA/SAC) System for Flexible Access Communications

    NASA Technical Reports Server (NTRS)

    Lee, Ricard Q.; Clark, Eric B.; Pal, Anna Maria T.; Wilt, David M.; Mueller, Carl H.

    2004-01-01

    Present satellite communications systems normally use separate solar cells and antennas. Since solar cells generally account for the largest surface area of the spacecraft, co-locating the antenna and solar cells on the same substrate opens the possibility for a number of data-rate-enhancing communications link architecture that would have minimal impact on spacecraft weight and size. The idea of integrating printed planar antenna and solar array cells on the same surface has been reported in the literature. The early work merely attempted to demonstrate the feasibility by placing commercial solar cells besides a patch antenna. Recently, Integrating multiple antenna elements and solar cell arrays on the same surface was reported for both space and terrestrial applications. The application of photovoltaic solar cell in a planar antenna structure where the radiating patch antenna is replaced by a Si solar cell has been demonstrated in wireless communication systems (C. Bendel, J. Kirchhof and N. Henze, 3rd Would Photovotaic Congress, Osaka, Japan, May 2003). Based on a hybrid approach, a 6x1 slot array with circularly polarized crossdipole elements co-located on the same surface of the solar cells array has been demonstrated (S. Vaccaro, J. R. Mosig and P. de Maagt, IEEE Trans. Ant. and Propag., Vol. 5 1, No. 8, Aug. 2003). Amorphous silicon solar cells with about 5-10% efficiency were used in these demonstrations. This paper describes recent effort to integrate advanced solar cells with printed planar antennas. Compared to prior art, the proposed WSAC concept is unique in the following ways: 1) Active antenna element will be used to achieve dynamic beam steering; 2) High efficiency (30%) GaAs multi-junction solar cells will be used instead of Si, which has an efficiency of about 15%; 3) Antenna and solar cells are integrated on a common GaAs substrate; and 4) Higher data rate capability. The IA/SAC is designed to operate at X-band (8-12 GH) and higher frequencies

  3. Low-cost solar array structure development

    NASA Technical Reports Server (NTRS)

    Wilson, A. H.

    1981-01-01

    Early studies of flat-plate arrays have projected costs on the order of $50/square meter for installed array support structures. This report describes an optimized low-cost frame-truss structure that is estimated to cost below $25/square meter, including all markups, shipping an installation. The structure utilizes a planar frame made of members formed from light-gauge galvanized steel sheet and is supposed in the field by treated-wood trusses that are partially buried in trenches. The buried trusses use the overburden soil to carry uplift wind loads and thus to obviate reinforced-concrete foundations. Details of the concept, including design rationale, fabrication and assembly experience, structural testing and fabrication drawings are included.

  4. Solar Wind observations using the Mexican Array Radio Telescope (MEXART)

    NASA Astrophysics Data System (ADS)

    Romero-Hernandez, E.; Gonzalez-Esparza, A.; Villanueva, P.; Aguilar-Rodriguez, E.; Mejia-Ambriz, J. C.; Mexart

    2013-05-01

    The Mexican Array Radiotelescope (MEXART) is an instrument devoted to observations of radio sources to study large-scale structures in the solar wind employing the Interplanetary Scintillation (IPS) technique. We report recent IPS observations, from January to April of 2013, including an analysis of the scintillation index and the estimation of solar wind velocities for a set of radio sources. We track the first ICMEs registered by the MEXART. We are initiating a continuos operation for a complete monitoring of IPS radio sources that will complement solar wind studies based on in-situ observations.

  5. Assessment of High-Voltage Photovoltaic Technologies for the Design of a Direct Drive Hall Effect Thruster Solar Array

    NASA Technical Reports Server (NTRS)

    Mikellides, I. G.; Jongeward, G. A.; Schneider, T.; Carruth, M. R.; Peterson, T.; Kerslake, T. W.; Snyder, D.; Ferguson, D.; Hoskins, A.

    2004-01-01

    A three-year program to develop a Direct Drive Hall-Effect Thruster system (D2HET) begun in 2001 as part of the NASA Advanced Cross-Enterprise Technology Development initiative. The system, which is expected to reduce significantly the power processing, complexity, weight, and cost over conventional low-voltage systems, will employ solar arrays that operate at voltages higher than (or equal to) 300 V. The lessons learned from the development of the technology also promise to become a stepping-stone for the production of the next generation of power systems employing high voltage solar arrays. This paper summarizes the results from experiments conducted mainly at the NASA Marshal Space Flight Center with two main solar array technologies. The experiments focused on electron collection and arcing studies, when the solar cells operated at high voltages. The tests utilized small coupons representative of each solar array technology. A hollow cathode was used to emulate parts of the induced environment on the solar arrays, mostly the low-energy charge-exchange plasma (1012-1013 m-3 and 0.5-1 eV). Results and conclusions from modeling of electron collection are also summarized. The observations from the total effort are used to propose a preliminary, new solar array design for 2 kW and 30-40 kW class, deep space missions that may employ a single or a cluster of Hall- Effect thrusters.

  6. Proceedings of the flat-plate solar array project research forum on photovoltaic metallization systems

    SciTech Connect

    1983-11-15

    A Photovoltaic Metallization Research Forum, under the sponsorship of the Jet Propulsion Laboratory's Flat-Plate Solar Array Project and the US Department of Energy, was held March 16-18, 1983 at Pine Mountain, Georgia. The Forum consisted of five sessions, covering (1) the current status of metallization systems, (2) system design, (3) thick-film metallization, (4) advanced techniques and (5) future metallization challenges. Twenty-three papers were presented.

  7. Better Thermal Insulation in Solar-Array Laminators

    NASA Technical Reports Server (NTRS)

    Burger, D. R.; Knox, J. F.

    1984-01-01

    Glass marbles improve temperature control. Modified vacuum laminator for photovoltaic solar arrays includes thermal insulation made of conventional glass marbles. Marbles serve as insulation for temperature control of lamination process at cure temperatures as high as 350 degrees F. Used to replace original insulation made of asbestos cement.

  8. Astronaut Story Musgrave deploys HST solar array panel

    NASA Technical Reports Server (NTRS)

    1993-01-01

    Astronaut F. Story Musgrave, anchored to a foot restraint on the Space Shuttle Endeavour's Remote Manipulator System (RMS) arm, aids the deployment of one of the solar array panels on the Hubble Space Telescope (HST). The action came during the final of five STS-61 space walks.

  9. Integrated Solar Array and Reflectarray Antenna for High Bandwidth Cubesats

    NASA Technical Reports Server (NTRS)

    Lewis, Dorothy; Martinez, Andres; Petro, Andrew

    2015-01-01

    The Integrated Solar Array and Reflectarray Antenna (ISARA) mission will demonstrate a reflectarray antenna that increases downlink data rates for Cube- Sats from the existing baseline rate of 9.6 kilobits per second (kbps) to more than 100 megabits per second (Mbps). The ISARA spacecraft is slated for launch no earlier than Dec. 1, 2015.

  10. Supporting Structures for Flat Solar-Cell Arrays

    NASA Technical Reports Server (NTRS)

    Wilson, A. H.

    1986-01-01

    Strong supporting structures for flat solar photovoltaic arrays built with such commonly available materials as wood and galvanized steel sheet. Structures resist expected static loads from snow and ice as well as dynamic loads from winds and even Earthquake vibrations. Supporting structure uses inexpensive materials. Parts prefabricated to minimize assembly work in field.

  11. Array of titanium dioxide nanostructures for solar energy utilization

    DOEpatents

    Qiu, Xiaofeng; Parans Paranthaman, Mariappan; Chi, Miaofang; Ivanov, Ilia N; Zhang, Zhenyu

    2014-12-30

    An array of titanium dioxide nanostructures for solar energy utilization includes a plurality of nanotubes, each nanotube including an outer layer coaxial with an inner layer, where the inner layer comprises p-type titanium dioxide and the outer layer comprises n-type titanium dioxide. An interface between the inner layer and the outer layer defines a p-n junction.

  12. Early Observations with the Expanded Owens Valley Solar Array

    NASA Astrophysics Data System (ADS)

    Gary, Dale E.

    2016-05-01

    The Expanded Owens Valley Solar Array (EOVSA) is a newly expanded and upgraded, solar-dedicated radio array consisting of 13 antennas of 2.1 m diameter equipped with receivers designed to cover the 1-18 GHz frequency range. Two large (27-m diameter) dishes are being outfitted with He-cooled receivers for use in calibration of the small dishes. During 2015, the array obtained observations from dozens of flares in total power mode on 8 antennas. Since February 2016, it has begun taking solar data on all 13 small antennas with full interferometric correlations, as well as calibration observations with the first of the two large antennas equipped with its He-cooled receiver. The second He-cooled receiver is nearly complete, and will be available around the time of the meeting. We briefly review the commissioning activities leading up to full operations, including polarization and gain measurements and calibration methods, and resulting measures of array performance. We then present some early imaging observations with the array, emphasizing the remarkable temporal and spectral resolution of the instrument, together with joint RHESSI hard X-ray and SDO EUV observations.

  13. Electricity from photovoltaic solar cells. Flat-Plate Solar Array Project of the US Department of Energy's National Photovoltaics Program: 10 years of progress

    NASA Technical Reports Server (NTRS)

    Christensen, Elmer

    1985-01-01

    The objectives were to develop the flat-plate photovoltaic (PV) array technologies required for large-scale terrestrial use late in the 1980s and in the 1990s; advance crystalline silicon PV technologies; develop the technologies required to convert thin-film PV research results into viable module and array technology; and to stimulate transfer of knowledge of advanced PV materials, solar cells, modules, and arrays to the PV community. Progress reached on attaining these goals, along with future recommendations are discussed.

  14. Computer Modelling and Simulation of Solar PV Array Characteristics

    NASA Astrophysics Data System (ADS)

    Gautam, Nalin Kumar

    2003-02-01

    The main objective of my PhD research work was to study the behaviour of inter-connected solar photovoltaic (PV) arrays. The approach involved the construction of mathematical models to investigate different types of research problems related to the energy yield, fault tolerance, efficiency and optimal sizing of inter-connected solar PV array systems. My research work can be divided into four different types of research problems: 1. Modeling of inter-connected solar PV array systems to investigate their electrical behavior, 2. Modeling of different inter-connected solar PV array networks to predict their expected operational lifetimes, 3. Modeling solar radiation estimation and its variability, and 4. Modeling of a coupled system to estimate the size of PV array and battery-bank in the stand-alone inter-connected solar PV system where the solar PV system depends on a system providing solar radiant energy. The successful application of mathematics to the above-m entioned problems entailed three phases: 1. The formulation of the problem in a mathematical form using numerical, optimization, probabilistic and statistical methods / techniques, 2. The translation of mathematical models using C++ to simulate them on a computer, and 3. The interpretation of the results to see how closely they correlated with the real data. Array is the most cost-intensive component of the solar PV system. Since the electrical performances as well as life properties of an array are highly sensitive to field conditions, different characteristics of the arrays, such as energy yield, operational lifetime, collector orientation, and optimal sizing were investigated in order to improve their efficiency, fault-tolerance and reliability. Three solar cell interconnection configurations in the array - series-parallel, total-cross-tied, and bridge-linked, were considered. The electrical characteristics of these configurations were investigated to find out one that is comparatively less susceptible to

  15. Solar Array at Very High Temperatures: Ground Tests

    NASA Technical Reports Server (NTRS)

    Vayner, Boris

    2016-01-01

    Solar array design for any spacecraft is determined by the orbit parameters. For example, operational voltage for spacecraft in Low Earth Orbit (LEO) is limited by significant differential charging due to interactions with low temperature plasma. In order to avoid arcing in LEO, solar array is designed to generate electrical power at comparatively low voltages (below 100 volts) or to operate at higher voltages with encapsulation of all suspected discharge locations. In Geosynchronous Orbit (GEO) differential charging is caused by energetic electrons that produce differential potential between the coverglass and the conductive spacecraft body in a kilovolt range. In such a case, the weakly conductive layer over coverglass, indium tin oxide (ITO) is one of the possible measures to eliminate dangerous discharges on array surface. Temperature variations for solar arrays in both orbits are measured and documented within the range of minus150 degrees Centigrade to plus 1100 degrees Centigrade. This wide interval of operational temperatures is regularly reproduced in ground tests with radiative heating and cooling inside a shroud with flowing liquid nitrogen. The requirements to solar array design and tests turn out to be more complicated when planned trajectory crosses these two orbits and goes closer to the Sun. The conductive layer over coverglass causes a sharp increase in parasitic current collected from LEO plasma, high temperature may cause cracks in encapsulating (Room Temperature Vulcanizing (RTV) material; radiative heating of a coupon in vacuum chamber becomes practically impossible above 1500 degrees Centigrade; conductivities of glass and adhesive go up with temperature that decrease array efficiency; and mechanical stresses grow up to critical magnitudes. A few test arrangements and respective results are presented in current paper. Coupons were tested against arcing in simulated LEO and GEO environments under elevated temperatures up to 2000 degrees

  16. Solar Array at Very High Temperatures: Ground Tests

    NASA Technical Reports Server (NTRS)

    Vayner, Boris

    2016-01-01

    Solar array design for any spacecraft is determined by the orbit parameters. For example, operational voltage for spacecraft in Low Earth Orbit (LEO) is limited by significant differential charging due to interactions with low temperature plasma. In order to avoid arcing in LEO, solar array is designed to generate electrical power at comparatively low voltages (below 100 V) or to operate at higher voltages with encapsulated of all suspected discharge locations. In Geosynchronous Orbit (GEO) differential charging is caused by energetic electrons that produce differential potential between coverglass and conductive spacecraft body in a kilovolt range. In such a case, weakly conductive layer over coverglass (ITO) is one of possible measures to eliminate dangerous discharges on array surface. Temperature variations for solar arrays in both orbits are measured and documented within the range of -150 C +110 C. This wide interval of operational temperatures is regularly reproduced in ground tests with radiative heating and cooling inside shroud with flowing liquid nitrogen. The requirements to solar array design and tests turn out to be more complicated when planned trajectory crosses these two orbits and goes closer to Sun. Conductive layer over coverglass causes sharp increase in parasitic current collected from LEO plasma, high temperature may cause cracks in encapsulating material (RTV), radiative heating of coupon in vacuum chamber becomes practically impossible above 150 C, conductivities of glass and adhesive go up with temperature that decrease array efficiency, and mechanical stresses grow up to critical magnitudes. A few test arrangements and respective results are presented in current paper. Coupons were tested against arcing in simulated LEO and GEO environments under elevated temperatures up to 200 C. The dependence of leakage current on temperature was measured, and electrostatic cleanness was verified for coupons with antireflection (AR) coating over ITO

  17. Thermoelastic analysis of solar cell arrays and their material properties

    NASA Technical Reports Server (NTRS)

    Salama, M. A.; Rowe, W. M.; Yasui, R. K.

    1973-01-01

    A thermoelastic stress analysis procedure is reported for predicting the thermally induced stresses and failures in silicon solar cell arrays. A prerequisite for the analysis is the characterization of the temperature-dependent thermal and mechanical properties of the solar cell materials. Extensive material property testing was carried out in the temperature range -200 to +200 C for the filter glass, P- and N-type silicon, interconnector metals, solder, and several candidate silicone rubber adhesives. The analysis procedure is applied to several solar cell array design configurations. Results of the analysis indicate the optimum design configuration, with respect to compatible materials, effect of the solder coating, and effect of the interconnector geometry. Good agreement was found between results of the analysis and the test program.

  18. Solar Array and Auroral Charging Studies of DMSP Spacecraft

    NASA Technical Reports Server (NTRS)

    Matias, Kelwin

    2013-01-01

    The SSJ electrostatic analyzers and the SSIES plasma instruments on the DMSP spacecraft in low Earth polar orbit can be used to conduct case studies of auroral and solar array charging. We will use a program written in the Interactive Data Language (IDL) to evaluate questionable charging events in the SSJ records by comparing charging signatures in SSJ and SSIES data. In addition, we will assemble a number of case studies of solar array charging showing the signatures from the SSJ data and compare them to the SSIES charging signatures. In addition, we will use Satellite Tool Kit (STK) to propagate orbits, obtain solar intensity, and use to verify onset of charging with sunrise.

  19. Stray light correction of array spectroradiometers for solar UV measurements.

    PubMed

    Nevas, Saulius; Gröbner, Julian; Egli, Luca; Blumthaler, Mario

    2014-07-01

    An approach is presented to characterize and correct stray light in spectra measured with array spectroradiometers and caused by out-of-spectral range radiation. A prerequisite for out-of-range stray light correction is knowledge of the spectral irradiance not measured by the instrument itself. A way of solving this problem for solar UV measurements is shown. The effect of out-of-range stray light is especially important for solar UV spectroradiometers typically having a spectral range narrower than that of the silicon detectors in use. Two different types of instruments used for solar UV measurements were characterized and corrected for out-of-range and in-range stray light. As a hardware solution to the out-of-range stray light problem, a bandpass filter was fitted in one array spectroradiometer. Results of test measurements using this modified instrument are also shown.

  20. Advancements in the micromirror array projector technology

    NASA Astrophysics Data System (ADS)

    Beasley, David B.; Bender, Matt W.; Crosby, Jay; Messer, Tim; Saylor, Daniel A.

    2003-09-01

    The Micromirror Array Projector System (MAPS) is a state-of-the-art dynamic scene projector developed by Optical Sciences Corporation (OSC) for Hardware-In-the-Loop (HWIL) simulation and sensor test applications. Since the introduction of the first MAPS in 2001, OSC has continued to improve the technology and develop systems for new projection and test applications. The MAPS is based upon the Texas Instruments Digital Micromirror Device (DMD) which has been modified to project high resolution, realistic imagery suitable for testing sensors and seekers operating in the UV, visible, NIR, and IR wavebands. This paper reviews the basic design and describes recent developments and new applications of the MAPS technology. Recent developments for the MAPS include increasing the format of the micromirror array to 1024x768 and increasing the binary frame rate to 10KHz. The MAPS technology has also been applied to the design of a Mobile Extended Spectrum Electro-Optical Test Set (MESEOTS). This test set is designed for testing UV, visible, NIR and IR sensors as well as laser rangefinders, laser trackers, and laser designators. The design and performance of the improved MAPS and the MESEOTS are discussed in paper.

  1. Diode Arrays and QA of Advanced Techniques

    NASA Astrophysics Data System (ADS)

    Gutiérrez PhD, Alonso N.; Calvo Msc, Oscar

    2010-11-01

    Dosimetric verification of delivery for intensity-modulated radiotherapy (IMRT) treatment plans is critical to ensure accurate and safe patient treatments. Commonly, a point dose measurement using a calibrated ion chamber as well as a planar dose measurement using film was traditionally implemented for dosimetric quality assurance (QA) of treatment plans. However, new products have become commercially available in which both an absolute and coarse planar dose measurements can be acquired simultaneously by the use of an array of detectors—either ion chamber- or diode-based. Currently, two devices, MapCHECK and Delta4, utilize diode technology for planar dose measurements with Delta4 implementing an orthogonal biplanar arrangement versus the common singular plane. Both devices have been thoroughly clinically characterized with more published experience in the literature available for the MapCHECK due to the novelty of Delta4. In this review, an overview of basic diode dosimetry and both diode array systems is presented with an emphasis on our research and clinical experience of the Delta4.

  2. Advanced Solar Observatory (ASO) accommodations requirements study

    NASA Technical Reports Server (NTRS)

    1989-01-01

    Results of an accommodations analysis for the Advanced Solar Observatory on Space Station Freedom are reported. Concepts for the High Resolution Telescope Cluster, Pinhole/Occulter Facility, and High Energy Cluster were developed which can be accommodated on Space Station Freedom. It is shown that workable accommodations concepts are possible. Areas of emphasis for the next stage of engineering development are identified.

  3. Integral Glass Encapsulation for Solar Arrays

    NASA Technical Reports Server (NTRS)

    Younger, P. R.; Tobin, R. G.; Kreisman, W. S.

    1979-01-01

    Work reported was performed during the period from August 1977 to December 1978. The program objective was to continue the development of electrostatic bonding (ESB) as an encapsulation technique for terrestrial cells. Economic analyses shows that this process can be a cost-effective method of producing reliable, long lifetime solar modules. When considered in sufficient volume, both material and equipment costs are competitive with conventional encapsulation systems. In addition, the possibility of integrating cell fabrication into the encapsulation process, as in the case of the preformed cell contacts discussed in this report, offers the potential of significant overall systems cost reduction.

  4. Solar Concentrator Advanced Development Program, Task 1

    NASA Technical Reports Server (NTRS)

    1986-01-01

    Solar dynamic power generation has been selected by NASA to provide power for the space station. Solar dynamic concentrator technology has been demonstrated for terrestrial applications but has not been developed for space applications. The object of the Solar Concentrator Advanced Development program is to develop the technology of solar concentrators which would be used on the space station. The first task of this program was to develop conceptual concentrator designs and perform trade-off studies and to develop a materials data base and perform material selection. Three unique concentrator concepts; Truss Hex, Spline Radial Panel and Domed Fresnel, were developed and evaluated against weighted trade criteria. The Truss Hex concept was recommended for the space station. Materials data base development demonstrated that several material systems are capable of withstanding extended periods of atomic oxygen exposure without undesirable performance degradation. Descriptions of the conceptual designs and materials test data are included.

  5. Advanced reflector materials for solar concentrators

    SciTech Connect

    Jorgensen, G; Williams, T; Wendelin, T

    1994-10-01

    This paper describes the research and development program at the U.S. National Renewable Energy Laboratory (NREL) in advanced reflector materials for solar concentrators. NREL's research thrust is to develop solar reflector materials that maintain high specular reflectance for extended lifetimes under outdoor service conditions and whose cost is significantly lower than existing products. Much of this work has been in collaboration with private-sector companies that have extensive expertise in vacuum-coating and polymer-film technologies. Significant progress and other promising developments will be discussed. These are expected to lead to additional improvements needed to commercialize solar thermal concentration systems and make them economically attractive to the solar manufacturing industry. To explicitly demonstrate the optical durability of candidate reflector materials in real-world service conditions, a network of instrumented outdoor exposure sites has been activated.

  6. Space satellite power system. [conversion of solar energy by photovoltaic solar cell arrays

    NASA Technical Reports Server (NTRS)

    Glaser, P. E.

    1974-01-01

    The concept of a satellite solar power station was studied. It is shown that it offers the potential to meet a significant portion of future energy needs, is pollution free, and is sparing of irreplaceable earth resources. Solar energy is converted by photovoltaic solar cell arrays to dc energy which in turn is converted into microwave energy in a large active phased array. The microwave energy is beamed to earth with little attenuation and is converted back to dc energy on the earth. Economic factors are considered.

  7. Flat-plate solar array project. Volume 3: Silicon sheet: Wafers and ribbons

    NASA Technical Reports Server (NTRS)

    Briglio, A.; Dumas, K.; Leipold, M.; Morrison, A.

    1986-01-01

    The primary objective of the Silicon Sheet Task of the Flat-Plate Solar Array (FSA) Project was the development of one or more low cost technologies for producing silicon sheet suitable for processing into cost-competitive solar cells. Silicon sheet refers to high purity crystalline silicon of size and thickness for fabrication into solar cells. Areas covered in the project were ingot growth and casting, wafering, ribbon growth, and other sheet technologies. The task made and fostered significant improvements in silicon sheet including processing of both ingot and ribbon technologies. An additional important outcome was the vastly improved understanding of the characteristics associated with high quality sheet, and the control of the parameters required for higher efficiency solar cells. Although significant sheet cost reductions were made, the technology advancements required to meet the task cost goals were not achieved.

  8. Expanded Owens Valley Solar Array (EOVSA) Testbed and Prototype

    NASA Astrophysics Data System (ADS)

    Gary, Dale E.; Nita, G. M.; Sane, N.

    2012-05-01

    NJIT is engaged in constructing a new solar-dedicated radio array, the Expanded Owens Valley Solar Array (EOVSA), which is slated for completion in late 2013. An initial 3-antenna array, the EOVSA Subsystem Testbed (EST), is now in operation from 1-9 GHz based on three of the old OVSA antennas, to test certain design elements of the new array. We describe this instrument and show some results from recent solar flares observed with it. We also describe plans for an upcoming prototype of EOVSA, which will use three antennas of the new design over the full 1-18 GHz signal chain of the entirely new system. The EOVSA prototype will be in operation by late 2012. Highlights of the new design are ability to cover the entire 1-18 GHz in less than 1 s, simultaneous dual polarization, and improved sensitivity and stability. We discuss what can be expected from the prototype, and how it will compare with the full 13-antenna EOVSA. This work was supported by NSF grants AGS-0961867 and AST-0908344, and NASA grant NNX11AB49G to New Jersey Institute of Technology.

  9. Thermal design of spacecraft solar arrays using a polyimide foam

    NASA Astrophysics Data System (ADS)

    Bianco, N.; Iasiello, M.; Naso, V.

    2015-11-01

    The design of the Thermal Control System (TCS) of spacecraft solar arrays plays a fundamental role. Indeed, the spacecraft components must operate within a certain range of temperature. If this doesn't occur, their performance is reduced and they may even break. Solar arrays, which are employed to recharge batteries, are directly exposed to the solar heat flux, and they need to be insulated from the earth's surface irradiation. Insulation is currently provided either with a white paint coating or with a Multi Layer Insulation (MLI) system [1]. A configuration based on an open-cell polyimide foam has also been recently proposed [2]. Using polyimide foams in TCSs looks very attractive in terms of costs, weight and assembling. An innovative thermal analysis of the above cited TCS configurations is carried out in this paper, by solving the porous media energy equation, under the assumption of Local Thermal Equilibrium (LTE) between the two phases. Radiation effects through the solar array are also considered by using the Rosseland approximation. Under a stationary daylight condition, temperature profiles are obtained by means of the finite-element based code COMSOL Multiphysics®. Finally, since the weight plays an important role in aerospace applications, weights of the three TCS configurations are compared.

  10. The Damper Spring Unit of the Sentinel 1 Solar Array

    NASA Technical Reports Server (NTRS)

    Doejaaren, Frans; Ellenbroek, Marcel

    2012-01-01

    The Damper Spring Unit (DSU, see Figure 1) has been designed to provide the damping required to control the deployment speed of the spring driven solar array deployment in an ARA Mk3 or FRED based Solar Array in situations where the standard application of a damper at the root-hinge is not feasible. The unit consists of four major parts: a main bracket, an eddy current damper, a spring unit, an actuation pulley which is coupled via Kevlar cables to a synchro-pulley of a hinge. The damper slows down the deployment speed and prevents deployment shocks at deployment completion. The spring unit includes 4 springs which overcome the resistances of the damper and the specific DSU control cable loop. This means it can be added to any spring driven deployment system without major modifications of that system. Engineering models of the Sentinel 1 solar array wing have been built to identify the deployment behavior, and to help to determine the optimal pulley ratios of the solar array and to finalize the DSU design. During the functional tests, the behavior proved to be very sensitive for the alignment of the DSU. This was therefore monitored carefully during the qualification program, especially prior to the TV cold testing. During TV "Cold" testing the measured retarding torque exceeded the max. required value: 284 N-mm versus the required 247 N-mm. Although this requirement was not met, the torque balance analysis shows that the 284 N-mm can be accepted, because the spring unit can provide 1.5 times more torque than required. Some functional tests of the DSU have been performed without the eddy current damper attached. It provided input data for the ADAMS solar array wing model. Simulation of the Sentinel-1 deployment (including DSU) in ADAMS allowed the actual wing deployment tests to be limited in both complexity and number of tests. The DSU for the Sentinel-1 solar array was successfully qualified and the flight models are in production.

  11. Research of control system stability in solar array simulator with continuous power amplifier of parallel type

    NASA Astrophysics Data System (ADS)

    Mizrah, E. A.; Tkachev, S. B.; Shtabel, N. V.

    2015-10-01

    Solar array simulators are nonlinear control systems designed to reproduce static and dynamic characteristics of solar array. Solar array characteristics depend on illumination, temperature, space environment and other causes. During on-earth testing of spacecraft power systems there is a problem reaching stable work of simulator with different impedance loads in wide range load regulation. In the article authors propose a research method for absolute process stability in solar array simulators and present results of absolute stability research for solar array simulator with continuous parallel type power amplifier.

  12. Energy requirement for the production of silicon solar arrays

    NASA Technical Reports Server (NTRS)

    Lindmayer, J.; Wihl, M.; Scheinine, A.; Rosenfield, T.; Wrigley, C. Y.; Morrison, A.; Anderson, J.; Clifford, A.; Lafky, W.

    1977-01-01

    The results of a study to investigate the feasibility of manufacturing photovoltaic solar array modules by the use of energy obtained from similar or identical photovoltaic sources are presented. The primary objective of this investigation was the characterization of the energy requirements of current and developing technologies which comprise the photovoltaic field. For cross-checking the energies of prevailing technologies data were also used and the wide-range assessment of alternative technologies included different refinement methods, various ways of producing light sheets, semicrystalline cells, etc. Energy data are utilized to model the behavior of a future solar breeder plant under various operational conditions.

  13. Development of a Solar Array Drive Assembly for CubeSat

    NASA Technical Reports Server (NTRS)

    Passaretti, Mike; Hayes, Ron

    2010-01-01

    Small satellites and in particular CubeSats, have increasingly become more viable as platforms for payloads typically requiring much larger bus structures. As advances in technology make payloads and instruments for space missions smaller, lighter and more power efficient, a niche market is emerging from the university community to perform rapidly developed, low-cost missions on very small spacecraft - micro, nano, and picosatellites. In just the last few years, imaging, biological and new technology demonstration missions have been either proposed or have flown using variations of the CubeSat structure as a basis. As these missions have become more complex, and the CubeSat standard has increased in both size (number of cubes) and mass, available power has become an issue. Body-mounted solar cells provide a minimal amount of power; deployable arrays improve on that baseline but are still limited. To truly achieve maximum power, deployed tracked arrays are necessary. To this end, Honeybee Robotics Spacecraft Mechanisms Corporation, along with MMA of Nederland Colorado, has developed a solar array drive assembly (SADA) and deployable solar arrays specifically for CubeSat missions. In this paper, we discuss the development of the SADA.

  14. Integrated Seismic Event Detection and Location by Advanced Array Processing

    SciTech Connect

    Kvaerna, T; Gibbons, S J; Ringdal, F; Harris, D B

    2007-02-09

    The principal objective of this two-year study is to develop and test a new advanced, automatic approach to seismic detection/location using array processing. We address a strategy to obtain significantly improved precision in the location of low-magnitude events compared with current fully-automatic approaches, combined with a low false alarm rate. We have developed and evaluated a prototype automatic system which uses as a basis regional array processing with fixed, carefully calibrated, site-specific parameters in conjuction with improved automatic phase onset time estimation. We have in parallel developed tools for Matched Field Processing for optimized detection and source-region identification of seismic signals. This narrow-band procedure aims to mitigate some of the causes of difficulty encountered using the standard array processing system, specifically complicated source-time histories of seismic events and shortcomings in the plane-wave approximation for seismic phase arrivals at regional arrays.

  15. Hubble gets new ESA-supplied solar arrays

    NASA Astrophysics Data System (ADS)

    1993-12-01

    Derek Eaton, ESA project manager, was overjoyed with the success of the day's spacewalk. "To build two such massive arrays some years apart to such tight tolerances and have one replace the other with so few problems is a tribute to the design and manufacturing skills of ESA and British Aerospace, the prime contractor for the arrays", he said. "The skill of Kathy and Tom contributed greatly to this success". The astronauts began their spacewalk at 09h30 p.m. CST (04h30 a.m. CET, Monday). Their first task was to jettison the troublesome solar array that failed to retract yesterday. Perched on the end of the shuttle's robot arm, 7.5 metres above the cargo bay, Thornton carefully released the array. ESA astronaut Claude Nicollier then pulled the arm away from the free-floating panel and mission commander Dick Covey fired the shuttle's thrusters to back away. Endeavour and the discarded array are moving apart at a rate of 18.5 kilometres each 90-minute orbit of the Earth. The array is expected to burn up in the Earth's atmosphere harmlessly within a year or so. The astronauts had no problems installing the new arrays and stowing the left-hand wing in the cargo bay for the return to Earth. The new arrays will remain rolled-up against the side of the telescope until the fifth spacewalk on Wednesday/Thursday. The telescope itself will be deployed on Saturday. The telescope's first set of arrays flexed in orbit because of the sudden swing in temperature as the craft moved in and out of sunlight. The movement, or "jitter", affected the telescope's pointing system and disrupted observations at times. The Space Telescope Operations Control Centre largely compensated for the problem with special software but this occupied a large amount of computer memory. The new arrays incorporate three major changes to eliminate the problem. The metal bi-stem booms, which support the solar blankets, is protected from extreme temperature changes by a concertina-style sleeve made up of one

  16. Quality assessment of solar UV irradiance measured with array spectroradiometers

    NASA Astrophysics Data System (ADS)

    Egli, Luca; Gröbner, Julian; Hülsen, Gregor; Bachmann, Luciano; Blumthaler, Mario; Dubard, Jimmy; Khazova, Marina; Kift, Richard; Hoogendijk, Kees; Serrano, Antonio; Smedley, Andrew; Vilaplana, José-Manuel

    2016-04-01

    The reliable quantification of ultraviolet (UV) radiation at the earth's surface requires accurate measurements of spectral global solar UV irradiance in order to determine the UV exposure to human skin and to understand long-term trends in this parameter. Array spectroradiometers (ASRMs) are small, light, robust and cost-effective instruments, and are increasingly used for spectral irradiance measurements. Within the European EMRP ENV03 project "Solar UV", new devices, guidelines and characterization methods have been developed to improve solar UV measurements with ASRMs, and support to the end user community has been provided. In order to assess the quality of 14 end user ASRMs, a solar UV intercomparison was held on the measurement platform of the World Radiation Center (PMOD/WRC) in Davos, Switzerland, from 10 to 17 July 2014. The results of the blind intercomparison revealed that ASRMs, currently used for solar UV measurements, show a large variation in the quality of their solar UV measurements. Most of the instruments overestimate the erythema-weighted UV index - in particular at large solar zenith angles - due to stray light contribution in the UV-B range. The spectral analysis of global solar UV irradiance further supported the finding that the uncertainties in the UV-B range are very large due to stray light contribution in this wavelength range. In summary, the UV index may be detected by some commercially available ASRMs within 5 % compared to the world reference spectroradiometer, if well characterized and calibrated, but only for a limited range of solar zenith angles. Generally, the tested instruments are not yet suitable for solar UV measurements for the entire range between 290 and 400 nm under all atmospheric conditions.

  17. Efficient structures for geosynchronous spacecraft solar arrays, phase 4

    NASA Technical Reports Server (NTRS)

    Adams, L. R.

    1982-01-01

    Efficient structures for geosynchronous spacecraft solar arrays were investigated. The STACBEAM (stacking triangular articulated compact beam) concept was selected. The primary component, the solar array blanket, is stored in a folded configuration and is deployed by controlled linear extension. Blanket stiffness is attained by axially tensioning the blanket and by providing periodic lateral ribs and standoffs which attach the blanket to the beam at several places along its length. The STACBEAM deploys sequentially (one bay at a time) using a deployer of sufficient rigidity so that beam stiffness is not degraded during deployment. The beam does not rotate during deployment, thus making blanket beam attachment possible in the packaged condition. In addition to high bending stiffness, the STACBEAM possesses high torsional rigidity due to nonflexible diagonals. The concept is adaptable to various size and loading requirements by changing member diameter and baylength, thus affecting the ratio of packaged and deployed length.

  18. Low-cost solar array progress and plans

    NASA Technical Reports Server (NTRS)

    Callaghan, W. T.

    1982-01-01

    It is pointed out that significant redirection has occurred in the U.S. Department of Energy (DOE) Photovoltaics Program, and thus in the Flat-Plate Solar Array Project (FSA), since the 3rd European Communities Conference. The Silicon Materials Task has now the objective to sponsor theoretical and experimental research on silicon material refinement technology suitable for photovoltaic flat-plate solar arrays. With respect to the hydrochlorination reaction, a process proof of concept was completed through definition of reaction kinetics, catalyst, and reaction characteristics. In connection with the dichlorosilane chemical vapor desposition process, a preliminary design was completed of an experimental process system development unit with a capacity of 100 to 200 MT/yr of Si.Attention is also given to the silicon-sheet formation research area, environmental isolation research, the cell and module formation task, the engineering sciences area, and the module performance and failure analysis area.

  19. Proceedings of the Flat-Plate Solar Array Project Research Forum on the Design of Flat-Plate Photovoltaic Arrays for Central Stations

    NASA Technical Reports Server (NTRS)

    1983-01-01

    The Flat Plate Solar Array Project, focuses on advancing technologies relevant to the design and construction of megawatt level central station systems. Photovoltaic modules and arrays for flat plate central station or other large scale electric power production facilities require the establishment of a technical base that resolves design issues and results in practical and cost effective configurations. Design, qualification and maintenance issues related to central station arrays derived from the engineering and operating experiences of early applications and parallel laboratory reserch activities are investigated. Technical issues are examined from the viewpoint of the utility engineer, architect/engineer and laboratory researcher. Topics on optimum source circuit designs, module insulation design for high system voltages, array safety, structural interface design, measurements, and array operation and maintenance are discussed.

  20. Proceedings of the Flat-Plate Solar Array Project Research Forum on the Design of Flat-Plate Photovoltaic Arrays for Central Stations

    NASA Astrophysics Data System (ADS)

    The Flat Plate Solar Array Project, focuses on advancing technologies relevant to the design and construction of megawatt level central station systems. Photovoltaic modules and arrays for flat plate central station or other large scale electric power production facilities require the establishment of a technical base that resolves design issues and results in practical and cost effective configurations. Design, qualification and maintenance issues related to central station arrays derived from the engineering and operating experiences of early applications and parallel laboratory reserch activities are investigated. Technical issues are examined from the viewpoint of the utility engineer, architect/engineer and laboratory researcher. Topics on optimum source circuit designs, module insulation design for high system voltages, array safety, structural interface design, measurements, and array operation and maintenance are discussed.

  1. A Nitinol-Based Solar Array Deployment Mechanism

    NASA Technical Reports Server (NTRS)

    Choi, Shin John; Lu, Chia-Ao; Feland, John

    1996-01-01

    This document describes a simple, light weight, and scalable mechanism capable of deploying flexible or rigid substrate solar arrays that have been configured in an accordion-like folding scheme. This mechanism is unique in that it incorporates a Shape Memory Alloy (SMA) actuator made of Nitinol. This paper documents the design of the mechanism in full detail while offering to designers a foundation of knowledge by which they can develop future applications with SMA's.

  2. Test of concentrator solar array model for SEPS

    NASA Technical Reports Server (NTRS)

    Huie, H. H.

    1979-01-01

    The use of concentrators to improve the performance of solar arrays in deep space was tested in a simulated deep space environment. The results of these tests are presented and discussed. Areas of discussion include cell temperature performance in a low temperature, low illumination environment with and without concentration, concentration ratios, and theoretical analysis versus test results. Tests were conducted on a series/parallel configuration and individual cells.

  3. Solar cell array design handbook - The principles and technology of photovoltaic energy conversion

    NASA Technical Reports Server (NTRS)

    Rauschenbach, H. S.

    1980-01-01

    Photovoltaic solar cell array design and technology for ground-based and space applications are discussed from the user's point of view. Solar array systems are described, with attention given to array concepts, historical development, applications and performance, and the analysis of array characteristics, circuits, components, performance and reliability is examined. Aspects of solar cell array design considered include the design process, photovoltaic system and detailed array design, and the design of array thermal, radiation shielding and electromagnetic components. Attention is then given to the characteristics and design of the separate components of solar arrays, including the solar cells, optical elements and mechanical elements, and the fabrication, testing, environmental conditions and effects and material properties of arrays and their components are discussed.

  4. Thermally-induced structural motions of satellite solar arrays

    NASA Astrophysics Data System (ADS)

    Johnston, John Dennis

    1999-11-01

    Satellites have experienced attitude disturbances resulting from thermally. induced structural motions of flexible appendages since the early days of the space program. Thermally-induced structural motions are typically initiated during orbital eclipse transitions when a satellite exits from or enters into the Earth's shadow. The accompanying rapid changes in thermal loading may lead to time-varying temperature differences through the cross-section of appendages resulting in differential thermal expansion and corresponding structural deformations. Since the total angular momentum of the system must be conserved, motions of flexible appendages such as booms and solar arrays result in rigid body rotations of the entire satellite. These potentially large attitude disturbances may violate satellite pointing and jitter requirements. This research investigates thermally-induced structural motions of rigid panel solar arrays (solar panels) through analytical and experimental studies. Orbital eclipse transition heating and thermal analyses were completed to study solar panel thermal behavior and provide results for input to dynamics analyses. A hybrid coordinate dynamical model was utilized to study the planar dynamics of a simple satellite consisting of a rigid hub with a cantilevered flexible solar panel undergoing thermally-induced structural motions. Laboratory experimental studies were carried out to gain new insight into thermal-structural behavior and to validate analytical models. The experimental studies investigated the thermal-structural performance of honeycomb sandwich panels and satellite solar panel hardware subject to simulated eclipse transition heating. Results from the analytical and experimental studies illustrate the importance of the through-the-thickness temperature difference and its time derivatives as well as the ratio of the characteristic thermal and structural response times in solar panel thermally-induced structural motions. The thermal

  5. Analyses of Contaminated Solar Array Handrail Samples Retrieved from Mir

    NASA Technical Reports Server (NTRS)

    deGroh, Kim K.; McCue, Terry R.

    1999-01-01

    In January 1998 during, the STS-89 mission, an eight section Russian solar array panel was retrieved after more than ten years exposure to the orbital space environment on the Russian space station Mir. Two darkened handrail samples from the Russian solar array have been evaluated for contamination: a section of a white paint covered rigid handrail and a section of woven fabric over-wrapped around a flexible handhold. The handrail samples were evaluated using optical microscopy (OM), field emission scanning electron microscopy (FESEM) and energy dispersive spectroscopy (EDS). Optical properties were also obtained. Microscopy has shown the discolored areas to have thick layers of contaminant that has crazed and spalled off in regions. Energy dispersive spectroscopy revealed that the brown contaminant is composed of oxidized silicon. No silicon was present on the unexposed fabric over-wrap, and very small amounts were present in the white paint. Therefore, the contaminant layer on both samples is attributed to silicone contamination from other spacecraft materials that have been oxidized by atomic oxygen while in orbit. A significant source of the silicone contamination appears to be from the solar array itself.

  6. Studies of encapsulant materials for terrestrial solar-cell arrays

    NASA Technical Reports Server (NTRS)

    Carmichael, D. C. (Compiler)

    1975-01-01

    Study 1 of this contract is entitled ""Evaluation of World Experience and Properties of Materials for Encapsulation of Terrestrial Solar-Cell Arrays.'' The approach of this study is to review and analyze world experience and to compile data on properties of encapsulants for photovoltaic cells and for related applications. The objective of the effort is to recommend candidate materials and processes for encapsulating terrestrial photovoltaic arrays at low cost for a service life greater than 20 years. The objectives of Study 2, ""Definition of Encapsulant Service Environments and Test Conditions,'' are to develop the climatic/environmental data required to define the frequency and duration of detrimental environmental conditions in a 20-year array lifetime and to develop a corresponding test schedule for encapsulant systems.

  7. Solar array model corrections from Mars Pathfinder lander data

    SciTech Connect

    Ewell, R.C.; Burger, D.R.

    1997-12-31

    The MESUR solar array power model initially assumed values for input variables. After landing early surface variables such as array tilt and azimuth or early environmental variables such as array temperature can be corrected. Correction of later environmental variables such as tau versus time, spectral shift, dust deposition, and UV darkening is dependent upon time, on-board science instruments, and ability to separate effects of variables. Engineering estimates had to be made for additional shadow losses and Voc sensor temperature corrections. Some variations had not been expected such as tau versus time of day, and spectral shift versus time of day. Additions needed to the model are thermal mass of lander petal and correction between Voc sensor and temperature sensor. Conclusions are: the model works well; good battery predictions are difficult; inclusion of Isc and Voc sensors was valuable; and the IMP and MAE science experiments greatly assisted the data analysis and model correction.

  8. Brazilian Decimetre Array (Phase-1): Initial solar observations

    NASA Astrophysics Data System (ADS)

    Ramesh, R.; Sawant, H. S.; Cecatto, J. R.; Faria, C.; Fernandes, F. C. R.; Kathiravan, C.; Suryanarayana, G. S.

    An East-West one-dimensional radio interferometer array consisting of 5 parabolic dish antennas has been set-up at Cachoeira Paulista, Brazil (Longitude: 45°0'20″W, Latitude: 22°41'19″S) for observations of Sun and some of the strong sidereal sources by the Instituto Nacional de Pesquisas Espaciais (INPE), Brazil. This is Phase-1 of the proposed Brazilian Decimetre Array (BDA) and can be operated at any frequency in the range 1.2-1.7 GHz. The instrument is functional since November 2004 onwards at 1.6 GHz. The angular and temporal resolution at the above frequency range are ˜3' and 100 ms, respectively. We present here the initial solar observations carried out with this array.

  9. Glass for low-cost photovoltaic solar arrays

    NASA Technical Reports Server (NTRS)

    Bouquet, F. L.

    1980-01-01

    Various aspects of glass encapsulation that are important for the designer of photovoltaic systems are discussed. Candidate glasses and available information defining the state of the art of glass encapsulation materials and processes for automated, high volume production of terrestrial photovoltaic devices and related applications are presented. The criteria for consideration of the glass encapsulation systems were based on the low-cost solar array project goals for arrays: (1) a low degradation rate, (2) high reliability, (3) an efficiency greater than 10 percent, (4) a total array price less than $500/kW, and (5) a production capacity of 500,000 kW/yr. The glass design areas discussed include the types of glass, sources and costs, physical properties, and glass modifications, such as antireflection coatings.

  10. Flat-plate solar array project. Volume 1: Executive summary

    NASA Technical Reports Server (NTRS)

    Callaghan, W.; Mcdonald, R.

    1986-01-01

    In 1975, the U.S. Government contracted the Jet Propulsion Lab. to develop, by 1985, in conjunction with industry, the photovoltaics (PV) module and array technology required for widespread use of photovoltaics as a significant terrestrial energy source. As a result, a project that eventually became known as the Flat Plate Solar Array (FSA) Project was formed to manage an industry, university, and Government team to perform the necessary research and development. The original goals were to achieve widespread commercial use of PV modules and arrays through the development of technology that would allow them to be profitably sold for $1.07/peak watts (1985 dollars). A 10% module conversion efficiency and a 20 year lifetime were also goals. It is intended that the executive summary provide the means by which one can gain a perspective on 11 years of terrestrial photovoltaic research and development conducted by the FSA Project.

  11. Bepi Colombo Mercury Magnetospheric Orbiter Solar Array Development

    NASA Astrophysics Data System (ADS)

    Toyota, Hiroyuki; Shimada, Takanobu; Kukita, Akio; Hirose, Kazuyuki; Ogawa, Hiroyuki; Hayakawa, Hajime; Maejima, Hironori; Tajima, Michio; Imaizumi, Mitsuru; Watabe, Hirokazu; Nozaki, Yukishige; Okamoto, Akira; Hisamatsu, Tadashi; Shimada, Keiji; Nakamura, Kazuyo; Takamoto, Tatsuya

    2011-10-01

    This paper reports the development process of the solar array for the Mercury probe called the Mercury Magnetospheric Orbiter. Because the spacecraft is going be exposed to intense sunlight up to 11 suns, the temperature of the solar array is expected to reach as high as 230oC. We evaluated the degradation in the electrical output of the solar cells by using high intensity and high temperature (HIHT) tests, and found out that a decrease in the transmittance of the DC93-500 adhesive caused by UV irradiation at high temperature led to decreased current output. By using coverglasses, which effectively cut the UV light, we could successfully minimize the decrease in the electrical output. We subjected coupon panels to a thermal vacuum test. We found an unusually large number of solar cells detaching from the substrate, which would lead to increased temperature, and cracked cells. We assumed that this problem was caused by interconnects whose stress reliefs were buried in adhesive due to a requirement of the scientific instruments. We increased the gap between adjacent cells to allow the stress reliefs to work effectively. We also conducted a proton irradiation test at 180oC to evaluate radiation damage at high temperature. The damage was confirmed to be identical to that at room temperature.

  12. Solar Array Module Plasma Interaction Experiment (SAMPIE): Technical requirements document

    NASA Technical Reports Server (NTRS)

    Hillard, G. Barry; Ferguson, Dale C.

    1992-01-01

    The Solar Array Module Plasma Interactions Experiment (SAMPIE) is a NASA shuttle space flight experiment scheduled for launch in early 1994. The SAMPIE experiment will investigate plasma interactions of high voltage space power systems in low earth orbit. Solar cell modules, representing several technologies, will be biased to high voltages to characterize both arcing and plasma current collection. Other solar modules, specially modified in accordance with current theories of arcing and breakdown, will demonstrate the possibility of arc suppression. Finally, several test modules will be included to study the basic nature of these interactions. The science and technology goals for the project are defined in the Technical Requirements Document (TRD) which is presented here.

  13. Efficient Multiterminal Spectrum Splitting via a Nanowire Array Solar Cell

    PubMed Central

    2015-01-01

    Nanowire-based solar cells opened a new avenue for increasing conversion efficiency and rationalizing material use by growing different III–V materials on silicon substrates. Here, we propose a multiterminal nanowire solar cell design with a theoretical conversion efficiency of 48.3% utilizing an efficient lateral spectrum splitting between three different III–V material nanowire arrays grown on a flat silicon substrate. This allows choosing an ideal material combination to achieve the proper spectrum splitting as well as fabrication feasibility. The high efficiency is possible due to an enhanced absorption cross-section of standing nanowires and optimization of the geometric parameters. Furthermore, we propose a multiterminal contacting scheme that can be fabricated with a technology close to standard CMOS. As an alternative we also consider a single power source with a module level voltage matching. These new concepts open avenues for next-generation solar cells for terrestrial and space applications. PMID:26878027

  14. Bonding machine for forming a solar array strip

    NASA Technical Reports Server (NTRS)

    Costogue, E. N.; Downing, R. G.; Middleton, O.; Mueller, R. L.; Yasui, R. K.; Cairo, F. J.; Person, J. K. (Inventor)

    1979-01-01

    A machine is described for attaching solar cells to a flexable substrate on which printed circuitry has been deposited. The strip is fed through: (1) a station in which solar cells are elevated into engagement with solder pads for the printed circuitry and thereafter heated by an infrared lamp; (2) a station at which flux and solder residue is removed; (3) a station at which electrical performance of the soldered cells is determined; (4) a station at which an encapsulating resin is deposited on the cells; (5) a station at which the encapsulated solar cells are examined for electrical performance; and (6) a final station at which the resulting array is wound on a takeup drum.

  15. Advanced Technology Solar Telescope Construction: Progress Report

    NASA Astrophysics Data System (ADS)

    Rimmele, Thomas R.; McMullin, J.; Keil, S.; Goode, P.; Knoelker, M.; Kuhn, J.; Rosner, R.; ATST Team

    2012-05-01

    The 4m Advance Technology Solar Telescope (ATST) on Haleakala will be the most powerful solar telescope and the world’s leading ground-based resource for studying solar magnetism that controls the solar wind, flares, coronal mass ejections and variability in the Sun’s output. The ATST will provide high resolution and high sensitivity observations of the dynamic solar magnetic fields throughout the solar atmosphere, including the corona at infrared wavelengths. With its 4 m aperture, ATST will resolve magnetic features at their intrinsic scales. A high order adaptive optics system delivers a corrected beam to the initial set of five state-of-the-art, facility class instrumentation located in the coude laboratory facility. Photopheric and chromospheric magnetometry is part of the key mission of four of these instruments. Coronal magnetometry and spectroscopy will be performed by two of these instruments at infrared wavelengths. The ATST project has transitioned from design and development to its construction phase. Site construction is expected to begin in April 2012. The project has awarded design and fabrication contracts for major telescope subsystems. A robust instrument program has been established and all instruments have passed preliminary design reviews or critical design reviews. A brief overview of the science goals and observational requirements of the ATST will be given, followed by a summary of the project status of the telescope and discussion of the approach to integrating instruments into the facility. The National Science Foundation (NSF) through the National Solar Observatory (NSO) funds the ATST Project. The NSO is operated under a cooperative agreement between the Association of Universities for Research in Astronomy, Inc. (AURA) and NSF.

  16. Impact of Solar Array Position on ISS Vehicle Charging

    NASA Technical Reports Server (NTRS)

    Alred, John; Mikatarian, Ronald; Koontz, Steve

    2006-01-01

    The International Space Station (ISS), because of its large structure and high voltage solar arrays, has a complex plasma interaction with the ionosphere in low Earth orbit (LEO). This interaction of the ISS US Segment photovoltaic (PV) power system with the LEO ionospheric plasma produces floating potentials on conducting elements of the ISS structure relative to the local plasma environment. To control the ISS floating potentials, two Plasma Contactor Units (PCUs) are installed on the Z1 truss. Each PCU discharges accumulated electrons from the Space Station structure, thus reducing the potential difference between the ISS structure and the surrounding charged plasma environment. Operations of the PCUs were intended to keep the ISS floating potential to 40 Volts (Reference 1). Exposed dielectric surfaces overlying conducting structure on the Space Station will collect an opposite charge from the ionosphere as the ISS charges. In theory, when an Extravehicular Activity (EVA) crewmember is tethered to structure via the crew safety tether or when metallic surfaces of the Extravehicular Mobility Unit (EMU) come in contact with conducting metallic surfaces of the ISS, the EMU conducting components, including the perspiration-soaked crewmember inside, can become charged to the Space Station floating potential. The concern is the potential dielectric breakdown of anodized aluminum surfaces on the EMU producing an arc from the EMU to the ambient plasma, or nearby ISS structure. If the EMU arcs, an electrical current of an unknown magnitude and duration may conduct through the EVA crewmember, producing an unacceptable condition. This electrical current may be sufficient to startle or fatally shock the EVA crewmember (Reference 2). Hence, as currently defined by the EVA community, the ISS floating potential for all nominal and contingency EVA worksites and translation paths must have a magnitude less than 40 volts relative to the local ionosphere at all times during EVA

  17. Amorphous silicon cell array powered solar tracking apparatus

    DOEpatents

    Hanak, Joseph J.

    1985-01-01

    An array of an even number of amorphous silicon solar cells are serially connected between first and second terminals of opposite polarity. The terminals are connected to one input terminal of a DC motor whose other input terminal is connected to the mid-cell of the serial array. Vane elements are adjacent the end cells to selectively shadow one or the other of the end cells when the array is oriented from a desired attitude relative to the sun. The shadowing of one cell of a group of cells on one side of the mid-cell reduces the power of that group substantially so that full power from the group of cells on the other side of the mid-cell drives the motor to reorient the array to the desired attitude. The cell groups each have a full power output at the power rating of the motor. When the array is at the desired attitude the power output of the two groups of cells balances due to their opposite polarity so that the motor remains unpowered.

  18. Solar array shuttle flight experiment - hardware development and testing

    SciTech Connect

    Elms, R.V.; Hill, H.C.; Young, L.E.

    1982-09-01

    This paper reports on the fabrication and ground testing of a large area, light-weight, flexible substrate developmental solar array wing that has been built for NASA-MSFC (Contract NAS8-31352) and of the supporting structure and data acquisition system (DAS) which, with the wing will be flown in the shuttle as an experiment in 1984. The experiment will verify the dynamics, thermodynamic, and electrical performance predictions of the array wing and will demonstrate the structural capability of the array wing for Orbiter launch and re-entry environments. The accomodation of the Shuttle payload requirements has resulted in several array wing and operation modifications since the ground demonstration of the array wing in the technology development program. The experiment hardware verification program was designed to minimize costs and risk of experiment performance degradation while maintaining shuttle and crew safety. The previous full-scale wing hardware tests included an extension mast water table test and wing testing for random vibration, thermal vacuum, and acoustic environments. The results of these tests were used to define wing design modifications and to scope the test program for the experiment hardware. The experiment hardware acceptance test program will be completed in October 1982.

  19. The Solar Array Photovoltaic Assembly for the INSAT 4CR Spacecraft Design, Development and In-Orbit Performance

    NASA Astrophysics Data System (ADS)

    Thomas, Joseph; Sudhakar, M.; Agarwal, Anil; Sankaran, M.; Mudramachary, P.

    2008-09-01

    The INSAT 4CR spacecraft, the third in the INSAT 4 series of Indian Space Research Organization (ISRO)'s Communication satellite program, is a high power communication satellite in Geo- stationary Earth Orbit (GEO), configured using the ISRO I2K bus. The primary power is provided by two-wing sun tracking, deployable solar array and the eclipse load requirement is supported by two 70 Ah nickel hydrogen batteries. The power output of the solar array is regulated by Sequential Switching Shunt Regulators to 42V±0.5V. The salient feature of the solar array design is that it uses the new generation multi junction solar cells for all the four panels of size 2.54m x 1.525m to meet the higher power requirement with the available array area. The solar panel fabrication process with the Advanced Triple Junction (ATJ) solar cells from M/s. EMCORE, USA, has been demonstrated for the GEO life cycle through qualification coupon fabrication and testing.This paper describes the INSAT 4CR solar array photovoltaic assemblies design, layout optimization and realization of the Flight Model (FM) panels. It focuses on the power generation prediction, electrical performance measurement under Large Area Pulsed Sun Simulator (LAPSS) and verification of the ground level test results. The indigenously built Geostationary Launch Vehicle (GSLV F04) has successfully launched the INSAT 4CR spacecraft into the orbit on September 2nd, 2007. This paper also presents the analysis of telemetry data to validate the initial phase in-orbit performance of the solar array with prediction.

  20. Glass for low-cost photovoltaic solar arrays

    SciTech Connect

    Bouquet, F.L.

    1980-02-01

    In photovoltaic systems, the encapsulant material that protects the solar cells should be highly transparent and very durable. Glass satisfies these two criteria and is considered a primary candidate for low-cost, photovoltaic encapsulation systems. In this report, various aspects of glass encapsulation are treated that are important for the designer of photovoltaic systems. Candidate glasses and available information defining the state of the art of glass encapsulation materials and processes for automated, high volume production of terrestrial photovoltaic devices and related applications are presented. The criteria for consideration of the glass encapsulation systems were based on the LSA (Low-cost Solar Array) Project goals for arrays: (a) a low degradation rate, (b) high reliability, (c) an efficiency greater than 10 percent, (d) a total array price less than $500/kW, and (e) a production capacity of 5 x 10/sup 5/ kW/yr. The glass design areas treated herein include the types of glass, sources and costs, physical properties and glass modifications, such as antireflection coatings. 78 references.

  1. Study program for encapsulation materials interface for low-cost solar array

    NASA Technical Reports Server (NTRS)

    Kaelble, D. H.; Mansfeld, F. B.; Kendig, M.; Leung, C.

    1981-01-01

    The service integrity of the bonded interface in solar cell modules used in solar arrays is addressed. The development of AC impedance as a nondestructive evaluation (NDE) methodology for solar arrays is reported along with development of corrosion models and materials selection criteria for corrosion resistant interfaces.

  2. Advanced indium antimonide monolithic charge coupled infrared imaging arrays

    NASA Technical Reports Server (NTRS)

    Koch, T. L.; Merilainen, C. A.; Thom, R. D.

    1981-01-01

    The continued process development of SiO2 insulators for use in advanced InSb monolithic charge coupled infrared imaging arrays is described. Specific investigations into the use of plasma enhanced chemical vapor deposited (PECVD) SiO2 as a gate insulator for InSb charge coupled devices is discussed, as are investigations of other chemical vapor deposited SiO2 materials.

  3. Convective Array Cooling for a Solar Powered Aircraft

    NASA Technical Reports Server (NTRS)

    Colozza, Anthony J.; Dolce, James (Technical Monitor)

    2003-01-01

    A general characteristic of photovoltaics is that they increase in efficiency as their operating temperature decreases. Based on this principal, the ability to increase a solar aircraft's performance by cooling the solar cells was examined. The solar cells were cooled by channeling some air underneath the cells and providing a convective cooling path to the back side of the array. A full energy balance and flow analysis of the air within the cooling passage was performed. The analysis was first performed on a preliminary level to estimate the benefits of the cooling passage. This analysis established a clear benefit to the cooling passage. Based on these results a more detailed analysis was performed. From this cell temperatures were calculated and array output power throughout a day period were determined with and without the cooling passage. The results showed that if the flow through the cooling passage remained laminar then the benefit in increased output power more than offset the drag induced by the cooling passage.

  4. The Long Wavelength Array (LWA): A Large HF/VHF Array for Solar Physics, Ionospheric Science, and Solar Radar

    NASA Astrophysics Data System (ADS)

    Kassim, N.; White, S.; Rodriquez, P.; Hartman, J.; Hicks, B.; Lazio, J.; Stewart, K.; Craig, J.; Taylor, G.; Cormier, C.; Romero, V.; Jenet, F.

    2010-09-01

    The Long Wavelength Array (LWA), currently under construction in New Mexico, will be an imaging HF/VHF interferometer providing a new approach for studying the Sun-Earth environment from the surface of the sun to the Earth’s ionosphere. The LWA will be a powerful tool for solar physics and space weather investigations, through its ability to characterize a diverse range of low-frequency, solar-related emissions, thereby increasing our understanding of particle acceleration and shocks in the solar atmosphere along with their impact on the Sun-Earth environment. As a passive receiver the LWA will directly detect Coronal Mass Ejections (CMEs) in emission, and indirectly through the scattering of cosmic background sources as they propagate towards Earth. If coupled with a suitable transmitter, the LWA would be an excellent receiver for solar radar, potentially demonstrating accurate geomagnetic storm prediction from the Earth’s surface. Both radar and passive receiving techniques could monitor the Sun-Earth environment during daytime as a compliment to nighttime space weather remote sensing techniques. The LWA will also naturally provide a measure of small-scale spatial and temporal ionospheric structure, a pre-requisite for accurate calibration and imaging of solar and space weather phenomena. As a sensitive monitor of differences in total electron content (TEC) through the ionosphere, the LWA will provide an unprecedented characterization of ionospheric turbulence and waves, capable of testing predictions of global ionospheric models with an aim towards improving their accuracy through input to physics-based models. As a fully digital, multi-beaming instrument, the LWA can monitor the Sun daily with a dedicated solar beam, while simultaneously pursuing ionospheric and astrophysics science programs both day and night. In this paper we present an overview of the LWA, currently under construction in New Mexico, and discuss the scientific goals of the project in the

  5. An IBM PC-based math model for space station solar array simulation

    NASA Technical Reports Server (NTRS)

    Emanuel, E. M.

    1986-01-01

    This report discusses and documents the design, development, and verification of a microcomputer-based solar cell math model for simulating the Space Station's solar array Initial Operational Capability (IOC) reference configuration. The array model is developed utilizing a linear solar cell dc math model requiring only five input parameters: short circuit current, open circuit voltage, maximum power voltage, maximum power current, and orbit inclination. The accuracy of this model is investigated using actual solar array on orbit electrical data derived from the Solar Array Flight Experiment/Dynamic Augmentation Experiment (SAFE/DAE), conducted during the STS-41D mission. This simulator provides real-time simulated performance data during the steady state portion of the Space Station orbit (i.e., array fully exposed to sunlight). Eclipse to sunlight transients and shadowing effects are not included in the analysis, but are discussed briefly. Integrating the Solar Array Simulator (SAS) into the Power Management and Distribution (PMAD) subsystem is also discussed.

  6. Technology for Solar Array Production on the Moon

    NASA Technical Reports Server (NTRS)

    Landis, Geoffrey A.

    2002-01-01

    Silicon, aluminum, and glass are the primary raw materials that will be required for production of solar arrays on the moon. A process sequence is proposed for producing these materials from lunar regolith is proposed, consisting of separating the required materials from lunar rock with fluorine. Fluorosilane produced by this process is reduced to silicon; the fluorine salts are reduced to metals by reaction with metallic potassium. Fluorine is recovered from residual MgF and CaF2 by reaction with K2O. Aluminum, calcium oxide, and magnesium oxide are recovered to manufacture structural materials and glass.

  7. Radial microwire array solar cell with pyramidal structure

    NASA Astrophysics Data System (ADS)

    Priyadarshini, Bindu; Das, Mukul Kumar; Sen, Mrinal; Kumar, Subindu

    2016-10-01

    In this work, a theoretical model for radial p-n junction microwire array solar cell with pyramidal structures in the space between microwires has been developed. Incorporation of pyramidal structures results in reflection of light, which would otherwise be unused, and illuminates side walls of the microwires. This additional illumination enhances absorption and, hence, efficiency of the whole structure. Efficiency enhancement is analyzed by varying different device parameters e.g., radius and length of each microwire and packing fraction of the structure. Results show that the maximum fractional efficiency enhancement can be obtained as 30% by suitable choice of these parameters.

  8. A digital controlled solar array regulator employing the charge control

    SciTech Connect

    Cho, Y.J.; Cho, B.H.

    1997-12-31

    A microprocessor controlled SAR system is presented. The inner analog loops employing the charge current control scheme continuously regulate the solar array output power according to the reference value generated by the ECU. The ECU consists of the peak power tracking and the battery charge current regulation algorithm. Modeling, analysis and a design procedure of the inner loops and the system loop are presented taking into account of interaction between the inner analog loops and the outer digital loops. Utilizing the inherent characteristics of the inner voltage and current loop, the system dynamic performance and stability can be optimized up to the speed limit of the microprocessor.

  9. Charging of flexible solar array substrates in kilovolt electron beams

    NASA Technical Reports Server (NTRS)

    Staskus, J. V.; Narciso, S. J.

    1978-01-01

    A series of survey tests were conducted to evaluate samples of flexible solar arrays. The samples used woven carbon fibers and/or coatings to increase the surface conductivity of the KAPTON substrate and thereby reduce surface charging. Four different samples were evaluated by exposing them to monoenergetic electron beams of 2 to 20 KeV at a current density of 1 nA sq cm. Simulated eclipse tests were also conducted. The results were as expected; the more continuous the conductive pattern, the lower the surface charging.

  10. Early Mission Power Assessment of the Dawn Solar Array

    NASA Technical Reports Server (NTRS)

    Stella, Paul M.; DiStefano, Salvatore; Rayman, Marc D.; Ulloa-Severino, Antonio

    2009-01-01

    NASA's Discovery Mission Dawn was launched in September 2007. Dawn will be the first to orbit two asteroids on a single voyage. The solar array for the Dawn mission will provide power under greatly varying illumination and temperature conditions. Dawn's ion propulsion system (IPS) will provide the spacecraft with enough thrust to reach Vesta and Ceres and orbit both. The demanding mission would be impossible without ion propulsion -- a mission only to the asteroid Vesta (and not including Ceres) would require a much more massive spacecraft and, a much larger launch vehicle.

  11. Status of wraparound contact solar cells and arrays

    NASA Technical Reports Server (NTRS)

    Baraona, C. R.; Young, L. E.

    1978-01-01

    Solar cells with wraparound contacts provide the following advantages in array assembly: (1) eliminate the need for discretely formed, damage susceptible series tabs; (2) eliminate the n gap problem by allowing the use of uniform covers over the entire cell surface; (3) allow a higher packing factor by reducing the additional series spacing formly required for forming, and routing the series tab; and (4) allow the cell bonding to the interconnect system to be a single-side function wherein series contacts can be made at the same time parallel contracts are made.

  12. SAMICS: Input data preparation. [Solar Array Manufacturing Industry Costing Standards

    NASA Technical Reports Server (NTRS)

    Chamberlain, R. G.; Aster, R. W.

    1979-01-01

    The Solar Array Manufacturing Industry Costing Standards (SAMICS) provide standard formats, data, assumptions, and procedures for estimating the price that a manufacturer would have to charge for the product of a specified manufacturing process sequence. A line-by-line explanation is given of those standard formats which describe the economically important characteristics of the manufacturing processes and the technological structure of the companies and the industry. This revision provides an updated presentation of Format A Process Description, consistent with the October 1978 version of that form. A checklist of items which should be entered on Format A as direct expenses is included.

  13. Iron-copper metallization for flexible solar/cell arrays

    NASA Technical Reports Server (NTRS)

    Lavendel, H. W.

    1983-01-01

    The feasibility of a copper-base metallization for shallow-junction cells applied in flexible solar arrays in space is discussed. This type of metallization will reduce usage of precious metals (such as silver), increase case of bonding (by welding or by soldering) and eliminate heavy high Z interconnects (such as molybdenum). The main points of concern are stability against thermally induced diffusion of copper into silicon which causes degradation of shallow cell junctions, and low series resistance of the contact with semiconductor which promotes cell efficiency.

  14. Development of a ninety string solar array simulator

    NASA Technical Reports Server (NTRS)

    Vasek, Thomas E.; Birchenough, Arthur G.

    1991-01-01

    A power source was developed to support testing for the Space Station Freedom Power Management and Distribution (PMAD) DC Testbed. The intent was to simulate as closely as possible the steady-state and transient responses of a solar array. Several breadboards and one thermal prototype were built and tested. Responses were successfully verified and improved upon during successive breadboards. The completed 90-string simulator consists of four power MOSFETs, four 25-watt source resistors, and four 250-watt drain source bypass resistors per string, in addition to the control circuitry.

  15. Development of a ninety string solar array simulator

    NASA Technical Reports Server (NTRS)

    Vasek, Thomas E.; Birchenough, Arthur G.

    1991-01-01

    A power source was developed to support testing for the Space Station Freedom Power Management and Distribution (PMAD) DC Testbed. The intent was to simulate as closely as possible the steady-state and transient responses of a solar array. Several breadboards and one thermal prototype were built and tested. Responses were successfully verified and improved upon during successive breadboards. The completed 90-string simulator consists of four power MOSFETs, four 25 watt source resistors, and four 250 watt drain source bypass resistors per string, in addition to the control circuitry.

  16. Develop Silicone Encapsulation Systems for Terrestrial Silicon Solar Arrays

    NASA Technical Reports Server (NTRS)

    1979-01-01

    The results of a study for Task 3 of the Low Cost Solar Array Project, directed toward the development of a cost effective encapsulation system for photovoltaic modules using silicon based materials, are reported. Results of the following are discussed: (1) weather-ometer stressing vs. weathering history of silicon and silicon modified materials; (2) humidity/temperature cycling exposure; (3) exposure at high humidity/high temperature; (4) outdoor exposure stress; (5) thermal cycling stress; and (6) UV screening agents. The plans for the next quarter are outlined.

  17. Threshold voltage for arcing on negatively biased solar arrays

    NASA Technical Reports Server (NTRS)

    Hastings, Daniel E.; Weyl, Guy; Kaufman, Donald

    1990-01-01

    The arcing that has been found to occur when negatively biased high-voltage solar arrays in LEO lie at a critical voltage with respect to the plasma environment is presently proposed to be due to a breakdown of gas emitted under electron bombardment from the solar cells' cover-glass. The elements of the model for this phenomenon include an electron current flow from the interconnect to a neighboring cover-glass, which desorbs neutral molecules under the electron bombardment. The neutral molecules form a gas over the interconnect, and this gas breaks down when the voltage over the interconnect is sufficiently high. Specific scaling predictions are made on the basis of the geometric structure and gas in question.

  18. Flat-plate solar array project. Volume 5: Process development

    NASA Technical Reports Server (NTRS)

    Gallagher, B.; Alexander, P.; Burger, D.

    1986-01-01

    The goal of the Process Development Area, as part of the Flat-Plate Solar Array (FSA) Project, was to develop and demonstrate solar cell fabrication and module assembly process technologies required to meet the cost, lifetime, production capacity, and performance goals of the FSA Project. R&D efforts expended by Government, Industry, and Universities in developing processes capable of meeting the projects goals during volume production conditions are summarized. The cost goals allocated for processing were demonstrated by small volume quantities that were extrapolated by cost analysis to large volume production. To provide proper focus and coverage of the process development effort, four separate technology sections are discussed: surface preparation, junction formation, metallization, and module assembly.

  19. Development of a model of space station solar array

    NASA Technical Reports Server (NTRS)

    Bosela, Paul A.

    1990-01-01

    Space structures, such as the space station solar arrays, must be extremely lightweight, flexible structures. Accurate prediction of the natural frequencies and mode shapes is essential for determining the structural adequacy of components, and designing a control system. The tension preload in the blanket of photovoltaic solar collectors, and the free/free boundary conditions of a structure in space, causes serious reservations on the use of standard finite element techniques of solution. In particular, a phenomena known as grounding, or false stiffening, of the stiffness matrix occurs during rigid body rotation. The grounding phenomena is examined in detail. Numerous stiffness matrices developed by others are examined for rigid body rotation capability, and found lacking. Various techniques are used for developing new stiffness matrices from the rigorous solutions of the differential equations, including the solution of the directed force problem. A new directed force stiffness matrix developed by the author provides all the rigid body capabilities for the beam in space.

  20. Flat-plate solar array project. Volume 7: Module encapsulation

    NASA Technical Reports Server (NTRS)

    Cuddihy, E.; Coulbert, C.; Gupta, A.; Liang, R.

    1986-01-01

    The objective of the Encapsulation Task was to develop, demonstrate, and qualify photovoltaic (PV) module encapsulation systems that would provide 20 year (later decreased to 30 year) life expectancies in terrestrial environments, and which would be compatible with the cost and performance goals of the Flat-Plate Solar Array (FSA) Project. The scope of the Encapsulation Task included the identification, development, and evaluation of material systems and configurations required to support and protect the optically and electrically active solar cell circuit components in the PV module operating environment. Encapsulation material technologies summarized include the development of low cost ultraviolet protection techniques, stable low cost pottants, soiling resistant coatings, electrical isolation criteria, processes for optimum interface bonding, and analytical and experimental tools for evaluating the long term durability and structural adequacy of encapsulated modules. Field testing, accelerated stress testing, and design studies have demonstrated that encapsulation materials, processes, and configurations are available that meet the FSA cost and performance goals.

  1. The Multi-Spectral Solar Telescope Array (MSSTA)

    NASA Technical Reports Server (NTRS)

    Walker, A. B. C., Jr.; Barbee, Troy W., Jr.; Hoover, Richard B.

    1997-01-01

    In 1987, our consortium pioneered the application of normal incidence multilayer X-ray optics to solar physics by obtaining the first high resolution narrow band, "thermally differentiated" images of the corona', using the emissions of the Fe IX/Fe X complex at ((lambda)lambda) approx. 171 A to 175 A, and He II Lyman (beta) at 256 A. Subsequently, we developed a rocket borne solar observatory, the Multi Spectral Solar Telescope Array (MSSTA) that pioneered multi-thermal imaging of the solar atmosphere, using high resolution narrow band X-ray, EUV and FUV optical systems. Analysis of MSSTA observations has resulted in four significant insights into the structure of the solar atmosphere: (1) the diameter of coronal loops is essentially constant along their length; (2) models of the thermal and density structure of polar plumes based on MSSTA observations have been shown to be consistent with the thesis that they are the source of high speed solar wind streams; (3) the magnetic structure of the footpoints of polar plumes is monopolar, and their thermal structure is consistent with the thesis that the chromosphere at their footpoints is heated by conduction from above; (4) coronal bright points are small loops, typically 3,500 - 20,000 km long (5 sec - 30 sec); their footpoints are located at the poles of bipolar magnetic structures that are are distinguished from other network elements by having a brighter Lyman a signature. Loop models derived for 26 bright points are consistent with the thesis that the chromosphere at their footpoints is heated by conduction from the corona.

  2. An analytical comparison of the efficiency of solar thermal collector arrays with and without external manifolds

    NASA Technical Reports Server (NTRS)

    1981-01-01

    An analytical comparison of the efficiency of solar thermal collector arrays with and without external manifolds is reported. A FORTRAN computer program was written for the computation of the thermal performance of solar thermal collector arrays with and without external manifolds. Arrays constructed from two example solar thermal collectors are computated. Typical external manifold sizes and thermal insulations are presented graphically and are compared with the thermal performance of the collector alone.

  3. Study of solar array switching power management technology for space power system

    NASA Technical Reports Server (NTRS)

    Cassinelli, J. E.

    1982-01-01

    This report documents work performed on the Solar Array Switching Power Management Study. Mission characteristics for three missions were defined to the depth necessary to determine their power management requirements. Solar array switching concepts which could satisfy the mission requirements were identified. The switching concepts were compared with a conventional buck regulator system for cost, weight and volume, reliability, efficiency and thermal control. Solar array switching provided significant advantages in all areas of comparison for the reviewed missions.

  4. Lightweight, Space and Power Efficient Solar Array Drive Design Implemented within Remote Interface Unit

    NASA Astrophysics Data System (ADS)

    Kivikyto, Tatu; Laaksoen, Jyrki

    2014-08-01

    PATRIA has implemented highly educated Remote Interface Units in various ESA missions. For the Sentinel-2 and EarthCARE it was constructed also to include Solar Array Drive Electronics. The same control design as for Solar Array Drive function was also piggybacked in Magneto Torque control drives and other mission specific stepper motor drives. The purpose of this paper is to summarise and present the PATRIA Solar Array Drive Electronics design advantages.

  5. Development of the solar array deployment and drive system for the XTE spacecraft

    NASA Technical Reports Server (NTRS)

    Farley, Rodger; Ngo, Son

    1995-01-01

    The X-ray Timing Explorer (XTE) spacecraft is a NASA science low-earth orbit explorer-class satellite to be launched in 1995, and is an in-house Goddard Space Flight Center (GSFC) project. It has two deployable aluminum honeycomb solar array wings with each wing being articulated by a single axis solar array drive assembly. This paper will address the design, the qualification testing, and the development problems as they surfaced of the Solar Array Deployment and Drive System.

  6. Solar array maximum power tracking with closed-loop control of a 30-centimeter ion thruster

    NASA Technical Reports Server (NTRS)

    Gruber, R. P.

    1977-01-01

    A new solar array/ion thruster system control concept has been developed and demonstrated. An ion thruster beam load is used to automatically and continuously operate an unregulated solar array at its maximum power point independent of variations in solar array voltage and current. Preliminary tests were run which verified that this method of control can be implemented with a few, physically small, signal level components dissipating less than two watts.

  7. Close up View of the Damaged and Partially Deployed Solar Array

    NASA Technical Reports Server (NTRS)

    1973-01-01

    This close up view of the damaged and partially deployed solar array panel was taken from the Skylab 2 Command/Service Module during its initial fly around inspecction before docking. The aluminum hold down strap which failed to release, preventing the solar array panel from deploying properly, can be seen in place and intact. The strap was later cut during an early mission EVA allowing the solar array panel to be deployed.

  8. Charging of the International Space Station Due to Its High Voltage Solar Arrays

    NASA Technical Reports Server (NTRS)

    Ferguson, Dale C.

    2002-01-01

    The International Space Station (ISS) has the highest voltage solar arrays ever flown in Low Earth Orbit (LEO). The ISS power system (and structure) ground is at the negative end of the 160 V solar arrays. Due to plasma current collection balance that must be maintained in LEO, it is possible for a spacecraft to charge negative of the ambient plasma by up to its entire solar array voltage (-160 V for ISS).

  9. Study of solar array switching power management technology for space power system

    NASA Technical Reports Server (NTRS)

    Cassinelli, J. E.

    1982-01-01

    This report documents work performed on the Solar Array Switching Power Management Study. Mission characteristics for three missions were defined to the depth necessary to determine their power management requirements. Solar array switching concepts were identified that could safisfy the mission requirements. These switching concepts were compared with a conventional buck regulator system on the basis of cost, weight and volume, reliability, efficiency and thermal control. For the missions reviewed, solar array switching provided significant advantages in all areas of comparison.

  10. Solar thermoelectricity via advanced latent heat storage

    NASA Astrophysics Data System (ADS)

    Olsen, M. L.; Rea, J.; Glatzmaier, G. C.; Hardin, C.; Oshman, C.; Vaughn, J.; Roark, T.; Raade, J. W.; Bradshaw, R. W.; Sharp, J.; Avery, A. D.; Bobela, D.; Bonner, R.; Weigand, R.; Campo, D.; Parilla, P. A.; Siegel, N. P.; Toberer, E. S.; Ginley, D. S.

    2016-05-01

    We report on a new modular, dispatchable, and cost-effective solar electricity-generating technology. Solar ThermoElectricity via Advanced Latent heat Storage (STEALS) integrates several state-of-the-art technologies to provide electricity on demand. In the envisioned STEALS system, concentrated sunlight is converted to heat at a solar absorber. The heat is then delivered to either a thermoelectric (TE) module for direct electricity generation, or to charge a phase change material for thermal energy storage, enabling subsequent generation during off-sun hours, or both for simultaneous electricity production and energy storage. The key to making STEALS a dispatchable technology lies in the development of a "thermal valve," which controls when heat is allowed to flow through the TE module, thus controlling when electricity is generated. The current project addresses each of the three major subcomponents, (i) the TE module, (ii) the thermal energy storage system, and (iii) the thermal valve. The project also includes system-level and techno- economic modeling of the envisioned integrated system and will culminate in the demonstration of a laboratory-scale STEALS prototype capable of generating 3kWe.

  11. Feasibility study of a 200 watt per kilogram lightweight solar array system. [for interplanetary spacecraft

    NASA Technical Reports Server (NTRS)

    Stanhouse, R.; Cokonis, J.; Rayl, G.

    1976-01-01

    Progress in an investigation of the feasibility of designing a lightweight solar array with a power-to-weight ratio of 200 watts per kilogram is described. This solar array will produce 10,000 watts of electrical power at 1 A.U. at its beginning of life (BOL), and degrade less than 20% over a three year period in interplanetary flight. A review of existing lightweight solar array system concepts is presented along with discussion pertaining to their applicable technology as it relates to a 200 watt/kilogram array. Also presented is a discussion of the candidate development solar cells being considered, and various deployable boom concepts under investigation.

  12. Solar array orientations for a space station in low earth orbit

    NASA Technical Reports Server (NTRS)

    Landis, Geoffrey A.; Lu, Cheng-Yi

    1991-01-01

    A large portion of the drag of a space station in LEO is generated by its solar array; for a baseline 25-kW solar array in 334-km orbit, 1800 kg of reboost propellant/year is needed to counteract solar array drag. A study is conducted of the drag reduction potential of three possible solar array orientations: sun-pointing, sun-pointing during illumination/edge-on during eclipse, and edge-on during entire orbit. An 18.5-percent drag-makeup propellant reduction is found to be obtainable with the sun-pointing/edge-on eclipse orientation technique.

  13. Design of a 7kW power transfer solar array drive mechanism

    NASA Technical Reports Server (NTRS)

    Sheppard, J. G.

    1982-01-01

    With the availability of the Shuttle and the European launcher, Ariane, there will be a continuing trend towards large payload satellite missions requiring high-power, high-inertia, flexible solar arrays. The need arises for a solar array drive with a large power transfer capability which can rotate these solar arrays without disturbing the satellite body pointing. The modular design of such a Solar Array Drive Mechanism (SADM) which is capable of transferring 7kW of power or more is described. Total design flexibility has been achieved, enabling different spacecraft power requirements to be accommodated within the SADM design.

  14. Inverted Silicon Nanopencil Array Solar Cells with Enhanced Contact Structures

    NASA Astrophysics Data System (ADS)

    Liang, Xiaoguang; Shu, Lei; Lin, Hao; Fang, Ming; Zhang, Heng; Dong, Guofa; Yip, Senpo; Xiu, Fei; Ho, Johnny C.

    2016-09-01

    Although three-dimensional nanostructured solar cells have attracted extensive research attention due to their superior broadband and omnidirectional light-harvesting properties, majority of them are still suffered from complicated fabrication processes as well as disappointed photovoltaic performances. Here, we employed our newly-developed, low-cost and simple wet anisotropic etching to fabricate hierarchical silicon nanostructured arrays with different solar cell contact design, followed by systematic investigations of their photovoltaic characteristics. Specifically, nano-arrays with the tapered tips (e.g. inverted nanopencils) are found to enable the more conformal top electrode deposition directly onto the nanostructures for better series and shunt conductance, but its insufficient film coverage at the basal plane would still restrict the charge carrier collection. In contrast, the low-platform contact design facilitates a substantial photovoltaic device performance enhancement of ~24%, as compared to the one of conventional top electrode design, due to the shortened current path and improved lateral conductance for the minimized carrier recombination and series resistance. This enhanced contact structure can not only maintain excellent photon-trapping behaviors of nanostructures, but also help to eliminate adverse impacts of these tapered nano-morphological features on the contact resistance, providing further insight into design consideration in optimizing the contact geometry for high-performance nanostructured photovoltaic devices.

  15. Inverted Silicon Nanopencil Array Solar Cells with Enhanced Contact Structures

    PubMed Central

    Liang, Xiaoguang; Shu, Lei; Lin, Hao; Fang, Ming; Zhang, Heng; Dong, Guofa; Yip, SenPo; Xiu, Fei; Ho, Johnny C.

    2016-01-01

    Although three-dimensional nanostructured solar cells have attracted extensive research attention due to their superior broadband and omnidirectional light-harvesting properties, majority of them are still suffered from complicated fabrication processes as well as disappointed photovoltaic performances. Here, we employed our newly-developed, low-cost and simple wet anisotropic etching to fabricate hierarchical silicon nanostructured arrays with different solar cell contact design, followed by systematic investigations of their photovoltaic characteristics. Specifically, nano-arrays with the tapered tips (e.g. inverted nanopencils) are found to enable the more conformal top electrode deposition directly onto the nanostructures for better series and shunt conductance, but its insufficient film coverage at the basal plane would still restrict the charge carrier collection. In contrast, the low-platform contact design facilitates a substantial photovoltaic device performance enhancement of ~24%, as compared to the one of conventional top electrode design, due to the shortened current path and improved lateral conductance for the minimized carrier recombination and series resistance. This enhanced contact structure can not only maintain excellent photon-trapping behaviors of nanostructures, but also help to eliminate adverse impacts of these tapered nano-morphological features on the contact resistance, providing further insight into design consideration in optimizing the contact geometry for high-performance nanostructured photovoltaic devices. PMID:27671709

  16. The effect of plasma on solar cell array arc characteristics

    NASA Technical Reports Server (NTRS)

    Snyder, D. B.; Tyree, E.

    1985-01-01

    The influence from the ambient plasma on the arc characteristics of a negatively biased solar cell array was investigated. The arc characteristics examined were the peak current during an arc, the decay time as the arc terminates, and the charge lost during the arc. These arc characteristics were examined in a nitrogen plasma with charge densities ranging from 15,000 to 45,000 cu cm. Background gas pressures ranged from 8x1,000,000 to 6x100,000 torr. Over these ranges of parameters no significant effect on the arc characteristics were seen. Arc characteristics were also examined for three gas species: helium, nitrogen and argon. The helium arcs have higher peak currents and shorter decay times than nitrogen and argon arcs. There are slight differences in the arc characteristics between nitrogen and argon. These differences may be caused by the differences in mass of the respective species. Also, evidence is presented for an electron emission mechanism appearing as a precursor to solar array arcs. Occasionally the plasma generator could be turned off, and currents could still be detected in the vacuum system. When these currents are presented, arcs may occur.

  17. The effect of plasma on solar cell array arc characteristics

    NASA Technical Reports Server (NTRS)

    Snyder, D. B.; Tyree, E.

    1984-01-01

    The influence from the ambient plasma on the arc characteristics of a negatively biased solar cell array was investigated. The arc characteristics examined were the peak current during an arc, the decay time as the arc terminates, and the charge lost during the arc. These arc characteristics were examined in a nitrogen plasma with charge densities ranging from 15,000 to 45,000 cu cm. Background gas pressures ranged from 8x1,000,000 to 6x100,000 torr. Over these ranges of parameters no significant effect on the arc characteristics were seen. Arc characteristics were also examined for three gas species: helium, nitrogen and argon. The helium arcs have higher peak currents and shorter decay times than nitrogen and argon arcs. There are slight differences in the arc characteristics between nitrogen and argon. These differences may be caused by the differences in mass of the respective species. Also, evidence is presented for an electron emission mechanism appearing as a precursor to solar array arcs. Occassionally the plasma generator could be turned off, and currents could still be detected in the vacuum system. When these currents are presented, arcs may occur.

  18. The Bepi Colombo Mercury Transfer Module And Mercury Planetary Orbiter Solar Array Design And Development

    NASA Astrophysics Data System (ADS)

    Petry, D.; Grunwald, C.; Lohberg, A.; Brandi, A.; Oxynos-Lauschke, C.; Andreev, T.; Van Der Ven, R.; Schuhmacher, U.; Fugger, S.; Caon, A.; Fiebrich, H. K.

    2011-10-01

    The Bepi Colombo Mercury Transfer Module (MTM) and Mercury Planetary Orbiter (MPO) solar arrays are being designedto guaranteethe operational requirements in a very severe environment, mainly characterized by high temperatures (up to 215°C including qualification margin) and high light intensity (up to 11 solar constants). Furthermore, the qualification of the MPO solar array requires 5000 thermal cycles between -165°C and 215°C. The final configurations of the solar arrays are the result of a very complex system analysis aiming at reducing the solar array operative temperatures. The outcome of these specific developments performed on the photovoltaic assembly and panel substrate materials are essential drivers of the solar array design activity. The MTM solar array is composed by two wings of five solar panels and provides a peak power of about 13000W during the 6-years cruise phase to Mercury. The MPO solar generator is composed of one wing of three panels and provides an average power up to about 1600W during the nominal 1 earth year mission around Mercury. The photovoltaic assembly of both solar arrays is based on newly designed GaAs triple-junction solar cells. New carbon fibre reinforced Cyanate structures are applied as substrates.

  19. The Automated Array Assembly Task of the Low-cost Silicon Solar Array Project, Phase 2

    NASA Technical Reports Server (NTRS)

    Coleman, M. G.; Grenon, L.; Pastirik, E. M.; Pryor, R. A.; Sparks, T. G.

    1978-01-01

    An advanced process sequence for manufacturing high efficiency solar cells and modules in a cost-effective manner is discussed. Emphasis is on process simplicity and minimizing consumed materials. The process sequence incorporates texture etching, plasma processes for damage removal and patterning, ion implantation, low pressure silicon nitride deposition, and plated metal. A reliable module design is presented. Specific process step developments are given. A detailed cost analysis was performed to indicate future areas of fruitful cost reduction effort. Recommendations for advanced investigations are included.

  20. A guide to measuring solar UV spectra using array spectroradiometers

    NASA Astrophysics Data System (ADS)

    Blumthaler, Mario; Gröbner, Julian; Egli, Luca; Nevas, Saulius

    2013-05-01

    Array spectroradiometers are cost-effective instruments allowing fast measurement sequences to monitor the high variability of solar radiation. From the spectra any desired biologically weighted doses within their operational spectral range can be derived by post-processing. Therefore, array spectroradiometers have the potential to replace filter radiometers currently used in UV monitoring networks. However, they suffer significantly from stray light. Thus for routine operation it is important to follow strict procedures for characterisation, operation and data post-processing, which are suggested in these guidelines. The most important characteristics of array spectroradiometers are wavelength calibration, slit function, stray light properties, spectral structure of the dark signal, linearity, noise equivalent irradiance and spectral responsivity. For routine operation, temperature stabilization is absolutely necessary as well as automated dark signal measurements. Integration time and number of repetitions control the noise level and they have to be defined according to the measurement requirements. Data post-processing includes consideration of nonlinearity, dark signal with its spectral structure, integration time, stray light correction, spectral response function and weighting function.

  1. Neural Network for Positioning Space Station Solar Arrays

    NASA Technical Reports Server (NTRS)

    Graham, Ronald E.; Lin, Paul P.

    1994-01-01

    As a shuttle approaches the Space Station Freedom for a rendezvous, the shuttle's reaction control jet firings pose a risk of excessive plume impingement loads on Freedom solar arrays. The current solution to this problem, in which the arrays are locked in a feathered position prior to the approach, may be neither accurate nor robust, and is also expensive. An alternative solution is proposed here: the active control of Freedom's beta gimbals during the approach, positioning the arrays dynamically in such a way that they remain feathered relative to the shuttle jet most likely to cause an impingement load. An artificial neural network is proposed as a means of determining the gimbal angles that would drive plume angle of attack to zero. Such a network would be both accurate and robust, and could be less expensive to implement than the current solution. A network was trained via backpropagation, and results, which compare favorably to the current solution as well as to some other alternatives, are presented. Other training options are currently being evaluated.

  2. Bypass Diode Temperature Tests of a Solar Array Coupon Under Space Thermal Environment Conditions

    NASA Technical Reports Server (NTRS)

    Wright, Kenneth H., Jr.; Schneider, Todd A.; Vaughn, Jason A.; Hoang, Bao; Wong, Frankie; Wu, Gordon

    2016-01-01

    Tests were performed on a 56-cell Advanced Triple Junction solar array coupon whose purpose was to determine margin available for bypass diodes integrated with new, large multi-junction solar cells that are manufactured from a 4-inch wafer. The tests were performed under high vacuum with coupon back side thermal conditions of both cold and ambient. The bypass diodes were subjected to a sequence of increasing discrete current steps from 0 Amp to 2.0 Amp in steps of 0.25 Amp. At each current step, a temperature measurement was obtained via remote viewing by an infrared camera. This paper discusses the experimental methodology, experiment results, and the thermal model.

  3. By-Pass Diode Temperature Tests of a Solar Array Coupon Under Space Thermal Environment Conditions

    NASA Technical Reports Server (NTRS)

    Wright, Kenneth H., Jr.; Schneider, Todd A.; Vaughn, Jason A.; Hoang, Bao; Wong, Frankie

    2016-01-01

    Tests were performed on a 56-cell Advanced Triple Junction solar array coupon whose purpose was to determine margin available for bypass diodes integrated with new, large multi-junction solar cells that are manufactured from a 4-inch wafer. The tests were performed under high vacuum with cold and ambient coupon back-side. The bypass diodes were subjected to a sequence of increasing discrete current steps from 0 Amp to 2.0 Amp in steps of 0.25 Amp. At each current step, a temperature measurement was obtained via remote viewing by an infrared camera. This paper discusses the experimental methodology, including the calibration of the thermal imaging system, and the results.

  4. Final Technical Report, City of Brockton Solar Brightfield: Deploying a Solar Array on a Brockton Brownfield

    SciTech Connect

    Ribeiro, Lori

    2007-08-23

    The City of Brockton, Massachusetts sought to install New England’s largest solar array at a remediated brownfield site on Grove Street. The 425-kilowatt solar photovoltaic array – or “Brightfield” – was installed in an urban park setting along with interpretive displays to maximize the educational opportunities. The “Brightfield” project included 1,395 310-Watt solar panels connected in “strings” that span the otherwise unusable 3.7-acre site. The project demonstrated that it is both technically and economically feasible to install utility scale solar photovoltaics on a capped landfill site. The US Department of Energy conceived the Brightfields program in 2000, and Brockton’s Brightfield is the largest such installation nationwide. Brockton’s project demonstrated that while it was both technically and economically feasible to perform such a project, the implementation was extremely challenging due to the state policy barriers, difficulty obtaining grant funding, and level of sophistication required to perform the financing and secure required state approvals. This demonstration project can be used as a model for other communities that wish to implement “Brownfields to Brightfields” projects; 2) implementing utility scale solar creates economies of scale that can help to decrease costs of photovoltaics; 3) the project is an aesthetic, environmental, educational and economic asset for the City of Brockton.

  5. Flat-plate solar array project. Volume 2: Silicon material

    NASA Technical Reports Server (NTRS)

    Lutwack, R.

    1986-01-01

    The goal of the Silicon Material Task, a part of the Flat Plate Solar Array (FSA) Project, was to develop and demonstate the technology for the low cost production of silicon of suitable purity to be used as the basic material for the manufacture of terrestrial photovoltaic solar cells. Summarized are 11 different processes for the production of silicon that were investigated and developed to varying extent by industrial, university, and Government researchers. The silane production section of the Union Carbide Corp. (UCC) silane process was developed completely in this program. Coupled with Siemens-type chemical vapor deposition reactors, the process was carried through the pilot stage. The overall UCC process involves the conversion of metallurgical-grade silicon to silane followed by decomposition of the silane to purified silicon. The other process developments are described to varying extents. Studies are reported on the effects of impurities in silicon on both silicon-material properties and on solar cell performance. These studies on the effects of impurities yielded extensive information and models for relating specific elemental concentrations to levels of deleterious effects.

  6. Solar Array Panels With Dust-Removal Capability

    NASA Technical Reports Server (NTRS)

    Dawson, Stephen; Mardesich, Nick; Spence, Brian; White, Steve

    2004-01-01

    It has been proposed to incorporate piezoelectric vibrational actuators into the structural supports of solar photovoltaic panels, for the purpose of occasionally inducing vibrations in the panels in order to loosen accumulated dust. Provided that the panels were tilted, the loosened dust would slide off under its own weight. Originally aimed at preventing obscuration of photovoltaic cells by dust accumulating in the Martian environment, the proposal may also offer an option for the design of solar photovoltaic panels for unattended operation at remote locations on Earth. The figure depicts a typical lightweight solar photovoltaic panel comprising a backside grid of structural spars that support a thin face sheet that, in turn, supports an array of photovoltaic cells on the front side. The backside structure includes node points where several spars intersect. According to the proposal, piezoelectric buzzers would be attached to the node points. The process of designing the panel would be an iterative one that would include computational simulation of the vibrations by use of finite- element analysis to guide the selection of the vibrational frequency of the actuators and the cross sections of the spars to maximize the agitation of dust.

  7. Solar Opacity Calculations Using the Super-transition-array Method

    NASA Astrophysics Data System (ADS)

    Krief, M.; Feigel, A.; Gazit, D.

    2016-04-01

    A new opacity model has been developed based on the Super-Transition-Array (STA) method for the calculation of monochromatic opacities of plasmas in local thermodynamic equilibrium. The atomic code, named STAR (STA-Revised), is described and used to calculate spectral opacities for a solar model implementing the recent AGSS09 composition. Calculations are carried out throughout the solar radiative zone. The relative contributions of different chemical elements and atomic processes to the total Rosseland mean opacity are analyzed in detail. Monochromatic opacities and charge-state distributions are compared with the widely used Opacity Project (OP) code, for several elements near the radiation-convection interface. STAR Rosseland opacities for the solar mixture show a very good agreement with OP and the OPAL opacity code throughout the radiation zone. Finally, an explicit STA calculation was performed of the full AGSS09 photospheric mixture, including all heavy metals. It was shown that, due to their extremely low abundance, and despite being very good photon absorbers, the heavy elements do not affect the Rosseland opacity.

  8. Approaches to Future Generation Photovoltaics and Solar Fuels: Quantum Dots, Arrays, and Quantum Dot Solar Cells

    SciTech Connect

    Semonin, O.; Luther, J.; Beard, M.; Johnson, J.; Gao, J.; Nozik, A.

    2012-01-01

    One potential, long-term approach to more efficient and lower cost future generation solar cells for solar electricity and solar fuels is to utilize the unique properties of quantum dots (QDs) to control the relaxation pathways of excited states to enhance multiple exciton generation (MEG). We have studied MEG in close-packed PbSe QD arrays where the QDs are electronically coupled in the films and thus exhibit good transport while still maintaining quantization and MEG. We have developed simple, all-inorganic solution-processable QD solar cells that produce large short-circuit photocurrents and power conversion efficiencies above 5% via nanocrystalline p-n junctions. These solar cells show QYs for photocurrent that exceed 100% in the photon energy regions where MEG is possible; the photocurrent MEG QYs as a function of photon energy match those determined via time-resolved spectroscopy Recent analyses of the major effect of MEG combined with solar concentration on the conversion efficiency of solar cells will also be discussed.

  9. Ultra-low-mass flexible planar solar arrays using 50-micron-thick solar cells

    NASA Technical Reports Server (NTRS)

    Costogue, E. N.; Rayl, G.

    1978-01-01

    A conceptual design study has been completed which has shown the feasibility of ultra-low-mass planar solar arrays with specific power of 200 watts/kilogram. The beginning of life (BOL) power output of the array designs would be 10 kW at 1 astronomical unit (AU) and a 55C deg operating temperature. Two designs were studied: a retractable rollout design and a non-retractable fold-out. The designs employed a flexible low-mass blanket and low-mass structures. The blanket utilized 2 x 2 cm high-efficiency (13.5% at 28C deg AM0), ultra-thin (50 micron), silicon solar cells protected by thin (75 micron) plastic encapsulants. The structural design utilized the 'V'-stiffened approach which allows a lower mass boom to be used. In conjunction with the conceptual design, modules using the thin cells and plastic encapsulant were designed and fabricated.

  10. The Advanced Technology Solar Telescope enclosure

    NASA Astrophysics Data System (ADS)

    Phelps, L.; Barr, J.; Dalrymple, N.; Fraser, M.; Hubbard, R.; Wagner, J.; Warner, M.

    2006-06-01

    Telescope enclosure design is based on an increasingly standard set of criteria. Enclosures must provide failsafe protection in a harsh environment for an irreplaceable piece of equipment; must allow effective air flushing to minimize local seeing while still attenuating wind-induced vibration of the telescope; must reliably operate so that the dome is never the reason for observatory down time; must provide access to utilities, lifting devices and support facilities; and they must be affordable within the overall project budget. The enclosure for the Advanced Technology Solar Telescope (ATST) has to satisfy all these challenging requirements plus one more. To eliminate so-called external dome seeing, the exterior surfaces of the enclosure must be maintained at or just below ambient air temperature while being subjected to the full solar loading of an observing day. Further complicating the design of the ATST enclosure and support facilities are the environmental sensitivities and high construction costs at the selected site - the summit of Haleakala on the island of Maui, Hawaii. Previous development work has determined an appropriate enclosure shape to minimize solar exposure while allowing effective interior flushing, and has demonstrated the feasibility of controlling the exterior skin temperature with an active cooling system. This paper presents the evolution of the design since site selection and how the enclosure and associated thermal systems have been tailored to the particular climatic and terrain conditions of the site. Also discussed are load-reduction strategies that have been identified through thermal modeling, CFD modeling, and other analyses to refine and economize the thermal control systems.

  11. The Long Wavelength Array: Imaging Solar Bursts and CMEs

    NASA Astrophysics Data System (ADS)

    Gopalswamy, N.; Lazio, T. J. W.; Kassim, N. E.; Erickson, W. C.

    1999-05-01

    Almost all of the transient disturbances in the Sun-Earth connected space are amenable to probing by metric and decametric radio wavelengths (150 MHz down to ionospheric cut-off at 15 MHz). The long wavelength radio imaging with polarization capability is virtually the only way of measuring magnetic fields in the outer corona and hence an important tool in the study of long-term evolution of the Sun as it sheds its magnetic field through coronal mass ejections (CMEs). Shocks generated during the CMEs are detected as type II radio bursts; some of the energetic electrons are detected as type III bursts; ejected plasmoids are observed as type IV bursts. Ionospheric effects used to pose a major problem for long wavelength imaging. We now know that most of the shortcomings due to ionospheric effects can be virtually eliminated, thanks to the development in image restoration such as self-calibration (Kassim and Erickson, 1998). Low frequency technologies are relatively cheap and well proven. A synergistic combination of a ground based Long Wavelength Array (LWA) and the space-borne coronagraphs such as on board the STEREO mission could prove to be an extremely powerful tool to understand the interplanetary propagation of solar disturbances. Passive imaging of solar emissions can also be combined with radar imaging to increase the scientific return of the LWA (see poster by Lazio et al). The low frequency regime has also the advantage of combining solar physics with non-solar radio astronomy: Sun in the day time and the rest of the universe at night (see poster by Kassim et al). NG is an NAS/NRC Senior Research Associate at NASA/GSFC on leave from the Catholic University. Basic research in radio astronomy at the Naval Research Laboratory is supported by the Office of Naval Research.

  12. Atomic Oxygen Durability Testing of an International Space Station Solar Array Validation Coupon

    NASA Technical Reports Server (NTRS)

    Forkapa, Mark J.; Stidham, Curtis; Banks, Bruce A.; Rutledge, Sharon K.; Ma, David H.; Sechkar, Edward A.

    1996-01-01

    An International Space Station solar array validation coupon was exposed in a directed atomic oxygen beam for space environment durability testing at the NASA Lewis Research Center. Exposure to atomic oxygen and intermittent tensioning of the solar array were conducted to verify the solar array#s durability to low Earth orbital atomic oxygen and to the docking threat of plume loading both of which are anticipated over its expected mission life of fifteen years. The validation coupon was mounted on a specially designed rotisserie. The rotisserie mounting enabled the solar and anti-solar facing side of the array to be exposed to directed atomic oxygen in a sweeping arrival process replicating space exposure. The rotisserie mounting also enabled tensioning, in order to examine the durability of the array and its hinge to simulated plume loads. Flash testing to verify electrical performance of the solar array was performed with a solar simulator before and after the exposure to atomic oxygen and tensile loading. Results of the flash testing indicated little or no degradation in the solar array#s performance. Photographs were also taken of the array before and after the durability testing and are included along with comparisons and discussions in this report. The amount of atomic oxygen damage appeared minor with the exception of a very few isolated defects. There were also no indications that the simulated plume loadings had weakened or damaged the array, even though there was some erosion of Kapton due to atomic oxygen attack. Based on the results of this testing, it is apparent that the International Space Station#s solar arrays should survive the low Earth orbital atomic oxygen environment and docking threats which are anticipated over its expected mission life.

  13. Advances in thin-film solar cells for lightweight space photovoltaic power

    NASA Technical Reports Server (NTRS)

    Landis, Geoffrey A.; Bailey, Sheila G.; Flood, Dennis J.

    1989-01-01

    The present stature and current research directions of photovoltaic arrays as primary power systems for space are reviewed. There have recently been great advances in the technology of thin-film solar cells for terrestrial applications. In a thin-film solar cell the thickness of the active element is only a few microns; transfer of this technology to space arrays could result in ultralow-weight solar arrays with potentially large gains in specific power. Recent advances in thin-film solar cells are reviewed, including polycrystalline copper-indium selenide (CuInSe2) and related I-III-VI2 compounds, polycrystalline cadmium telluride and related II-VI compounds, and amorphous silicon:hydrogen and alloys. The best experimental efficiency on thin-film solar cells to date is 12 percent AMO for CuIn Se2. This efficiency is likely to be increased in the next few years. The radiation tolerance of thin-film materials is far greater than that of single-crystal materials. CuIn Se2 shows no degradation when exposed to 1 MeV electrons. Experimental evidence also suggests that most of all of the radiation damage on thin-films can be removed by a low temperature anneal. The possibility of thin-film multibandgap cascade solar cells is discussed, including the tradeoffs between monolithic and mechanically stacked cells. The best current efficiency for a cascade is 12.5 percent AMO for an amorphous silicon on CuInSe2 multibandgap combination. Higher efficiencies are expected in the future. For several missions, including solar-electric propulsion, a manned Mars mission, and lunar exploration and manufacturing, thin-film photovolatic arrays may be a mission-enabling technology.

  14. Summary of flat-plate solar array project documentation: Abstracts of published documents, 1975-1986, revision 1

    NASA Astrophysics Data System (ADS)

    Phillips, M. J.

    1986-09-01

    s of final reports, or the latest quarterly or annual, of the Flat-Plate Solar Array (FSA) Project Contractor of Jet Propulsion Laboratory (JPL) in-house activities are presented. Also presented is a list of proceedings and publications, by author, of work connected with the project. The aim of the program has been to stimulate the development of technology that will enable the private sector to manufacture and widely use photovoltaic systems for the generation of electricity in residential, commercial, industrial, and Government applications at a cost per watt that is competitive with utility generated power. FSA Project activities have included the sponsoring of research and development efforts in silicon refinement processes, advanced silicon sheet growth techniques, higher efficiency solar cells, solar cell/module fabrication processes, encapsulation, module/array engineering and reliability, and economic analyses.

  15. Summary of flat-plate solar array project documentation: Abstracts of published documents, 1975-1986, revision 1

    NASA Technical Reports Server (NTRS)

    Phillips, M. J.

    1986-01-01

    Abstracts of final reports, or the latest quarterly or annual, of the Flat-Plate Solar Array (FSA) Project Contractor of Jet Propulsion Laboratory (JPL) in-house activities are presented. Also presented is a list of proceedings and publications, by author, of work connected with the project. The aim of the program has been to stimulate the development of technology that will enable the private sector to manufacture and widely use photovoltaic systems for the generation of electricity in residential, commercial, industrial, and Government applications at a cost per watt that is competitive with utility generated power. FSA Project activities have included the sponsoring of research and development efforts in silicon refinement processes, advanced silicon sheet growth techniques, higher efficiency solar cells, solar cell/module fabrication processes, encapsulation, module/array engineering and reliability, and economic analyses.

  16. Spoked wheels to deploy large surfaces in space-weight estimates for solar arrays

    NASA Technical Reports Server (NTRS)

    Crawford, R. F.; Hedgepeth, J. M.; Preiswerk, P. R.

    1975-01-01

    Extensible booms were used to deploy and support solar cell arrays of varying areas. Solar cell array systems were built with one or two booms to deploy and tension a blanket with attached cells and bussing. A segmented and hinged rim supported by spokes joined to a common hub is described. This structure can be compactly packaged and deployed.

  17. A Parametric Assessment of the Mission Applicability of Thin-film Solar Arrays

    NASA Technical Reports Server (NTRS)

    Hoffman, David J.

    2002-01-01

    Results are presented from a parametric assessment of the applicability and spacecraft-level impacts of very lightweight thin-film solar arrays with relatively large deployed areas for representative space missions. The most and least attractive features of thin-film solar arrays are briefly discussed. A calculation is then presented illustrating that from a solar array alone mass perspective, larger arrays with less efficient but lighter thin-film solar cells can weigh less than smaller arrays with more efficient but heavier crystalline cells. However, a spacecraft-level systems assessment must take into account the additional mass associated with solar array deployed area: the propellant needed to desaturate the momentum accumulated from area-related disturbance torques and to perform aerodynamic drag makeup reboost. The results for such an assessment are presented for a representative low Earth orbit (LEO) mission, as a function of altitude and mission life, and a geostationary Earth orbit (GEO) mission. Discussion of the results includes a list of specific mission types most likely to benefit from using thin-film arrays. The presentation concludes with a list of issues to be addressed prior to use of thin-film solar arrays in space and the observation that with their unique characteristics, very lightweight arrays using efficient, thin film cells on flexible substrates may become the best array option for a subset of Earth orbiting and deep space missions.

  18. Advanced Antenna-Coupled Superconducting Detector Arrays for CMB Polarimetry

    NASA Astrophysics Data System (ADS)

    Bock, James

    2014-01-01

    We are developing high-sensitivity millimeter-wave detector arrays for measuring the polarization of the cosmic microwave background (CMB). This development is directed to advance the technology readiness of the Inflation Probe mission in NASA's Physics of the Cosmos program. The Inflation Probe is a fourth-generation CMB satellite that will measure the polarization of the CMB to astrophysical limits, characterizing the inflationary polarization signal, mapping large-scale structure based on polarization induced by gravitational lensing, and mapping Galactic magnetic fields through measurements of polarized dust emission. The inflationary polarization signal is produced by a background of gravitational waves from the epoch of inflation, an exponential expansion of space-time in the early universe, with an amplitude that depends on the physical mechanism producing inflation. The inflationary polarization signal may be distinguished by its unique 'B-mode' vector properties from polarization from the density variations that predominantly source CMB temperature anisotropy. Mission concepts for the Inflation Probe are being developed in the US, Europe and Japan. The arrays are based on planar antennas that provide integral beam collimation, polarization analysis, and spectral band definition in a compact lithographed format that eliminates discrete fore-optics such as lenses and feedhorns. The antennas are coupled to transition-edge superconducting bolometers, read out with multiplexed SQUID current amplifiers. The superconducting sensors and readouts developed in this program share common technologies with NASA X-ray and FIR detector applications. Our program targets developments required for space observations, and we discuss our technical progress over the past two years and plans for future development. We are incorporating arrays into active sub-orbital and ground-based experiments, which advance technology readiness while producing state of the art CMB

  19. Interaction of a solar array with an ion thruster due to the charge-exchange plasma

    NASA Technical Reports Server (NTRS)

    Kaufman, H. R.

    1976-01-01

    The generation of a charge exchange plasma by a thruster, the transport of this plasma to the solar array, and the interaction of the solar array with the plasma after it arrives are all described. The generation of this plasma is described accurately from thruster geometry and operating conditions. The transport of the charge exchange plasma was studied experimentally with a 15 cm thruster. A model was developed for simple thruster array configurations. A variety of experiments were surveyed for the interaction of the plasma at the solar array.

  20. Artificial light-harvesting arrays for solar energy conversion.

    PubMed

    Harriman, Anthony

    2015-07-28

    Solar fuel production, the process whereby an energy-rich substance is produced using electrons provided by water under exposure to sunlight, requires the cooperative accumulation of multiple numbers of photons. Identifying the optimum reagents is a difficult challenge, even without imposing the restriction that these same materials must function as both sensitiser and catalyst. The blockade caused by an inadequate supply of photons at the catalytic sites might be resolved by making use of an artificial light-harvesting array whose sole purpose is to funnel photons of appropriate frequency to the active catalyst, which can now be a dark reagent. Here we consider several types of artificial photon collectors built from fluorescent modules interconnected via electronic energy transfer. Emphasis is placed on the materials aspects and on establishing the basic operating principles.

  1. Solar Array Sails: Possible Space Plasma Environmental Effects

    NASA Technical Reports Server (NTRS)

    Mackey, Willie R.

    2005-01-01

    An examination of the interactions between proposed "solar sail" propulsion systems with photovoltaic energy generation capabilities and the space plasma environments. Major areas of interactions ere: Acting from high voltage arrays, ram and wake effects, V and B current loops and EMI. Preliminary analysis indicates that arcing will be a major risk factor for voltages greater than 300V. Electron temperature enhancement in the wake will be produce noise that can be transmitted via the wake echo process. In addition, V and B induced potential will generate sheath voltages with potential tether like breakage effects in the thin film sails. Advocacy of further attention to these processes is emphasized so that plasma environmental mitigation will be instituted in photovoltaic sail design.

  2. Electronic system for high power load control. [solar arrays

    NASA Technical Reports Server (NTRS)

    Miller, E. L. (Inventor)

    1980-01-01

    Parallel current paths are divided into two groups, with control devices in the current paths of one group each having a current limiting resistor, and the control devices in the other group each having no limiting resistor, so that when the control devices of the second group are turned fully on, a short circuit is achieved by the arrangement of parallel current paths. Separate but coordinated control signals are provided to turn on the control devices of the first group and increase their conduction toward saturation as a function of control input, and when fully on, or shortly before, to turn on the control devices of the second group and increase their conduction toward saturation as a function of the control input as that input continues to increase. Electronic means may be used to generate signals. The system may be used for 1-V characteristic measurements of solar arrays as well as for other load control purposes.

  3. Materials Refining for Solar Array Production on the Moon

    NASA Technical Reports Server (NTRS)

    Landis, Geoffrey A.

    2005-01-01

    Silicon, aluminum, and glass are the primary raw materials that will be required for production of solar arrays on the moon. A process sequence is proposed for producing these materials from lunar regolith, consisting of separating the required materials from lunar rock with fluorine. The fluorine is brought to the moon in the form of potassium fluoride, and is liberated from the salt by electrolysis in a eutectic salt melt. Tetrafluorosilane produced by this process is reduced to silicon by a plasma reduction stage; the fluorine salts are reduced to metals by reaction with metallic potassium. Fluorine is recovered from residual MgF and CaF2 by reaction with K2O.

  4. Develop Silicone Encapsulation Systems for Terrestrial Silicon Solar Arrays

    NASA Technical Reports Server (NTRS)

    1979-01-01

    The results for Task 3 of the Low Cost Solar Array Project are presented. Task 3 is directed toward the development of a cost effective encapsulating system for photovoltaic modules using silicon based materials. The technical approach of the contract effort is divided into four special tasks: (1) technology review; (2) generation of concepts for screening and processing silicon encapsulation systems; (3) assessment of encapsulation concepts; and (4) evaluation of encapsulation concepts. The candidate silicon materials are reviewed. The silicon and modified silicon resins were chosen on the basis of similarity to materials with known weatherability, cost, initial tangential modulus, accelerated dirt pick-up test results and the ratio of the content of organic phenyl substitution of methyl substitution on the backbone of the silicon resin.

  5. High efficiency micro solar cells integrated with lens array

    NASA Astrophysics Data System (ADS)

    Fidaner, Onur; Suarez, Ferran A.; Wiemer, Michael; Sabnis, Vijit A.; Asano, Tetsuya; Itou, Akihiro; Inoue, Daijiro; Hayashi, Nobuhiko; Arase, Hidekazu; Matsushita, Akio; Nakagawa, Tohru

    2014-03-01

    We demonstrate high efficiency triple junction solar cells with submillimeter dimensions in an all-back-contact architecture. 550 × 550 μm2 cells flash at 41.3% efficiency under the air mass 1.5 direct normal spectrum at 50 W/cm2 at 25 °C. Compared to standard size production cells, the micro cells have reduced performance at 1-sun due to perimeter recombination, but the performance gap closes at higher concentrations. Micro cells integrated with lens arrays were tested on-sun with an efficiency of 34.7%. All-back-contact architecture and submillimeter dimensions are advantageous for module integration and heat dissipation, allowing for high-performance, compact, lightweight, and cost-effective concentrated photovoltaic modules.

  6. Options Studied for Managing Space Station Solar Array Electrical Hazards for Sequential Shunt Unit Replacement

    NASA Technical Reports Server (NTRS)

    Delleur, Ann M.; Kerslake, Thomas W.; Levy, Robert K.

    2004-01-01

    The U.S. solar array strings on the International Space Station are connected to a sequential shunt unit (SSU). The job of the SSU is to shunt, or short, the excess current from the solar array, such that just enough current is provided downstream to maintain the 160-V bus voltage while meeting the power load demand and recharging the batteries. Should an SSU fail on-orbit, it would be removed and replaced with the on-orbit spare during an astronaut space walk or extravehicular activity (EVA) (see the photograph). However, removing an SSU during an orbit Sun period with input solar array power connectors fully energized could result in substantial hardware damage and/or safety risk to the EVA astronaut. The open-circuit voltage of cold solar-array strings can exceed 320 V, and warm solar-array strings could feed a short circuit with a total current level exceeding 240 A.

  7. Deployment dynamics and control of large-scale flexible solar array system with deployable mast

    NASA Astrophysics Data System (ADS)

    Li, Hai-Quan; Liu, Xiao-Feng; Guo, Shao-Jing; Cai, Guo-Ping

    2016-10-01

    In this paper, deployment dynamics and control of large-scale flexible solar array system with deployable mast are investigated. The adopted solar array system is introduced firstly, including system configuration, deployable mast and solar arrays with several mechanisms. Then dynamic equation of the solar array system is established by the Jourdain velocity variation principle and a method for dynamics with topology changes is introduced. In addition, a PD controller with disturbance estimation is designed to eliminate the drift of spacecraft mainbody. Finally the validity of the dynamic model is verified through a comparison with ADAMS software and the deployment process and dynamic behavior of the system are studied in detail. Simulation results indicate that the proposed model is effective to describe the deployment dynamics of the large-scale flexible solar arrays and the proposed controller is practical to eliminate the drift of spacecraft mainbody.

  8. SAVANT: Solar Array Verification and Analysis Tool Demonstrated

    NASA Technical Reports Server (NTRS)

    Chock, Ricaurte

    2000-01-01

    The photovoltaics (PV) industry is now being held to strict specifications, such as end-oflife power requirements, that force them to overengineer their products to avoid contractual penalties. Such overengineering has been the only reliable way to meet such specifications. Unfortunately, it also results in a more costly process than is probably necessary. In our conversations with the PV industry, the issue of cost has been raised again and again. Consequently, the Photovoltaics and Space Environment Effects branch at the NASA Glenn Research Center at Lewis Field has been developing a software tool to address this problem. SAVANT, Glenn's tool for solar array verification and analysis is in the technology demonstration phase. Ongoing work has proven that more efficient and less costly PV designs should be possible by using SAVANT to predict the on-orbit life-cycle performance. The ultimate goal of the SAVANT project is to provide a user-friendly computer tool to predict PV on-orbit life-cycle performance. This should greatly simplify the tasks of scaling and designing the PV power component of any given flight or mission. By being able to predict how a particular PV article will perform, designers will be able to balance mission power requirements (both beginning-of-life and end-of-life) with survivability concerns such as power degradation due to radiation and/or contamination. Recent comparisons with actual flight data from the Photovoltaic Array Space Power Plus Diagnostics (PASP Plus) mission validate this approach.

  9. Effect of wind speed on performance of a solar-pv array

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Thousands of solar photovoltaic (PV) arrays have been installed over the past few years, but the effect of wind speed on the predicted performance of PV arrays is not usually considered by installers. An increase in wind speed will cool the PV array, and the electrical power of the PV modules will ...

  10. Concept for a high voltage solar array with integral power conditioning.

    NASA Technical Reports Server (NTRS)

    Wiener, P.; Rasmussen, R.

    1972-01-01

    Description of a general case solution that synthesizes a high voltage solar array system from a switchable building block concept which makes possible system optimization for specific load requirements. A specific optimized solution is demonstrated, with performance estimates relating array area, weight, and power. Significant technology problems peculiar to a high-voltage switchable solar array design are discussed, along with special requirements anticipated during a hardware development effort.

  11. Alignment and Initial Operation of an Advanced Solar Simulator

    NASA Technical Reports Server (NTRS)

    Jaworske, Donald A.; Jefferies, Kent S.; Mason, Lee S.

    1996-01-01

    A solar simulator utilizing nine 30-kW xenon arc lamps was built to provide radiant power for testing a solar dynamic space power system in a thermal vacuum environment. The advanced solar simulator achieved the following values specific to the solar dynamic system: (1) a subtense angle of 1 deg; (2) the ability to vary solar simulator intensity up to 1.7 kW/sq m; (3) a beam diameter of 4.8 m; and (4) uniformity of illumination on the order of +/-10%. The flexibility of the solar simulator design allows for other potential uses of the facility.

  12. Solar concentrator constructed with a circular prism array.

    PubMed

    Huang, Jia-hong; Fei, Wun-Ciang; Hsu, Wei-Chi; Tsai, Jui-che

    2010-08-10

    We present a novel idea to construct a solar concentrator with a circular prism array. FRED ray tracing software is used to evaluate our proposed structure in which the incident light rays are deflected by total internal reflection and the optical energy is concentrated and collected at the center. The light rays to be collected travel within the disk once they enter the module, saving the space that is reserved for ray propagation in other concentrators. Simulations for both single-wavelength and broadband light are performed. Our device can be used alone or serve as a secondary concentrator when combined with another solar-energy focusing module. For the proposed concentrator, an optical efficiency of 90% (single wavelength, 0.87 microm) is achieved under normal incidence and with antireflection coating, and a high geometric concentration ratio of 93 is reached. When combined with a Fresnel lens, which is used as a primary concentrator, the overall efficiency and concentration ratio can reach 92% (single wavelength, 0.87 microm) and 837, respectively.

  13. TAB interconnects for space concentrator solar cell arrays

    NASA Technical Reports Server (NTRS)

    Avery, J.; Bauman, J. S.; Gallagher, P.; Yerkes, J. W.

    1993-01-01

    The Boeing Company has evaluated the use of Tape Automated Bonding (TAB) and Surface Mount Technology (SMT) for a highly reliable, low cost interconnect for concentrator solar cell arrays. TAB and SMT are currently used in the electronics industry for chip interconnects and printed circuit board assembly. TAB tape consists of sixty-four 3-mil/1-oz tin-plated copper leads on 8-mil centers. The leads are thermocompression gang bonded to GaAs concentrator solar cell with silver contacts. This bond, known as an Inner Lead Bond (ILB), allows for pretesting and sorting capability via nondestruct wire bond pull and flash testing. Destructive wire pull tests resulted in preferred mid-span failures. Improvements in fill factor were attributed to decreased contact resistance on TAB bonded cells. Preliminary thermal cycling and aging tests were shown excellent bond strength and metallurgical results. Auger scans of bond sites reveals an Ag-Cu-Tin composition. Improper bonds are identified through flash testing as a performance degradation. On going testing of cells are underway at Lewis Research Center. SMT techniques are utilized to excise and form TAB leads post ILB. The formed leads' shape isolates thermal mismatches between the cells and the flex circuit they are mounted on. TABed cells are picked and placed with a gantry x-y-z positioning system with pattern recognition. Adhesives are selected to avoid thermal expansion mismatch and promote thermal transfer to the flex circuit. TAB outer lead bonds are parallel gap welded (PGW) to the flex circuit to finish the concentrator solar cell subassembly.

  14. Automated Array Assembly, Phase 2. Low-cost Solar Array Project, Task 4

    NASA Technical Reports Server (NTRS)

    Lopez, M.

    1978-01-01

    Work was done to verify the technological readiness of a select process sequence with respect to satisfying the Low Cost Solar Array Project objectives of meeting the designated goals of $.50 per peak watt in 1986 (1975 dollars). The sequence examined consisted of: (1) 3 inches diameter as-sawn Czochralski grown 1:0:0 silicon, (2) texture etching, (3) ion implanting, (4) laser annealing, (5) screen printing of ohmic contacts and (6) sprayed anti-reflective coatings. High volume production projections were made on the selected process sequence. Automated processing and movement of hardware at high rates were conceptualized to satisfy the PROJECT's 500 MW/yr capability. A production plan was formulated with flow diagrams integrating the various processes in the cell fabrication sequence.

  15. Flat-plate solar array project. Volume 4: High-efficiency solar cells

    NASA Technical Reports Server (NTRS)

    Leipold, M.; Cheng, L.; Daud, T.; Mokashi, A.; Burger, D.; Christensen, E. (Editor); Murry, J. (Editor); Bengelsdorf, I. (Editor)

    1986-01-01

    The High Efficiency Solar Cell Task was assigned the objective of understanding and developing high efficiency solar cell devices that would meet the cost and performance goals of the Flat Plate Solar Array (FSA) Project. The need for research dealing with high efficiency devices was considered important because of the role efficiency plays in reducing price per watt of generated energy. The R&D efforts conducted during the 1982 to 1986 period are summarized to provide understanding and control of energy conversion losses associated with crystalline silicon solar cells. New levels of conversion efficiency were demonstrated. Major contributions were made both to the understanding and reduction of bulk and surface losses in solar cells. For example, oxides, nitrides, and polysilicon were all shown to be potentially useful surface passivants. Improvements in measurement techniques were made and Auger coefficients and spectral absorption data were obtained for unique types of silicon sheets. New modelling software was developed including a program to optimize a device design based on input characteristics of a cell.

  16. Parametric study of two planar high power flexible solar array concepts

    NASA Technical Reports Server (NTRS)

    Garba, J. A.; Kudija, D. A.; Zeldin, B.; Costogue, E. N.

    1978-01-01

    The design parameters examined were: frequency, aspect ratio, packaging constraints, and array blanket flatness. Specific power-to-mass ratios for both solar arrays as a function of array frequency and array width were developed and plotted. Summaries of the baseline design data, developed equations, the computer program operation, plots of the parameters, and the process for using the information as a design manual are presented.

  17. Lightweight Inflatable Solar Array: Providing a Flexible, Efficient Solution to Space Power Systems for Small Spacecraft

    NASA Technical Reports Server (NTRS)

    Johnson, Les; Fabisinski, Leo; Justice, Stefanie

    2014-01-01

    Affordable and convenient access to electrical power is critical to consumers, spacecraft, military and other applications alike. In the aerospace industry, an increased emphasis on small satellite flights and a move toward CubeSat and NanoSat technologies, the need for systems that could package into a small stowage volume while still being able to power robust space missions has become more critical. As a result, the Marshall Space Flight Center's Advanced Concepts Office identified a need for more efficient, affordable, and smaller space power systems to trade in performing design and feasibility studies. The Lightweight Inflatable Solar Array (LISA), a concept designed, prototyped, and tested at the NASA Marshall Space Flight Center (MSFC) in Huntsville, Alabama provides an affordable, lightweight, scalable, and easily manufactured approach for power generation in space or on Earth. This flexible technology has many wide-ranging applications from serving small satellites to soldiers in the field. By using very thin, ultraflexible solar arrays adhered to an inflatable structure, a large area (and thus large amount of power) can be folded and packaged into a relatively small volume (shown in artist rendering in Figure 1 below). The proposed presentation will provide an overview of the progress to date on the LISA project as well as a look at its potential, with continued development, to revolutionize small spacecraft and portable terrestrial power systems.

  18. Thermal cycle testing of Space Station Freedom solar array blanket coupons

    NASA Technical Reports Server (NTRS)

    Scheiman, David A.; Schieman, David A.

    1991-01-01

    Lewis Research Center is presently conducting thermal cycle testing of solar array blanket coupons that represent the baseline design for Space Station Freedom. Four coupons were fabricated as part of the Photovoltaic Array Environment Protection (PAEP) Program, NAS 3-25079, at Lockheed Missile and Space Company. The objective of the testing is to demonstrate the durability or operational lifetime of the solar array welded interconnect design within the durability or operational lifetime of the solar array welded interconnect design within a low earth orbit (LEO) thermal cycling environment. Secondary objectives include the observation and identification of potential failure modes and effects that may occur within the solar array blanket coupons as a result of thermal cycling. The objectives, test articles, test chamber, performance evaluation, test requirements, and test results are presented for the successful completion of 60,000 thermal cycles.

  19. Photogrammetric Assessment of the Hubble Space Telescope Solar Arrays During the Second Servicing Mission

    NASA Technical Reports Server (NTRS)

    Sapp, C. A.; Dragg, J. L.; Snyder, M. W.; Gaunce, M. T.; Decker, J. E.

    1998-01-01

    This report documents the photogrammetric assessment of the Hubble Space Telescope (HST) solar arrays conducted by the NASA c Center Image Science and Analysis Group during Second Servicing Mission 2 (SM-2) on STS-82 in February 1997. Two type solar array analyses were conducted during the mission using Space Shuttle payload bay video: (1) measurement of solar array motion due to induced loads, and (2) measurement of the solar array static or geometric twist caused by the cumulative array loading. The report describes pre-mission planning and analysis technique development activities conducted to acquire and analyze solar array imagery data during SM-2. This includes analysis of array motion obtained during SM-1 as a proof-of-concept of the SM-2 measurement techniques. The report documents the results of real-time analysis conducted during the mission and subsequent analysis conducted post-flight. This report also provides a summary of lessons learned on solar array imagery analysis from SM-2 and recommendations for future on-orbit measurements applicable to HST SM-3 and to the International Space Station. This work was performed under the direction of the Goddard Space Flight Center HST Flight Systems and Servicing Project.

  20. Mir Cooperative Solar Array Flight Performance Data and Computational Analysis

    NASA Technical Reports Server (NTRS)

    Kerslake, Thomas W.; Hoffman, David J.

    1997-01-01

    The Mir Cooperative Solar Array (MCSA) was developed jointly by the United States (US) and Russia to provide approximately 6 kW of photovoltaic power to the Russian space station Mir. The MCSA was launched to Mir in November 1995 and installed on the Kvant-1 module in May 1996. Since the MCSA photovoltaic panel modules (PPMs) are nearly identical to those of the International Space Station (ISS) photovoltaic arrays, MCSA operation offered an opportunity to gather multi-year performance data on this technology prior to its implementation on ISS. Two specially designed test sequences were executed in June and December 1996 to measure MCSA performance. Each test period encompassed 3 orbital revolutions whereby the current produced by the MCSA channels was measured. The temperature of MCSA PPMs was also measured. To better interpret the MCSA flight data, a dedicated FORTRAN computer code was developed to predict the detailed thermal-electrical performance of the MCSA. Flight data compared very favorably with computational performance predictions. This indicated that the MCSA electrical performance was fully meeting pre-flight expectations. There were no measurable indications of unexpected or precipitous MCSA performance degradation due to contamination or other causes after 7 months of operation on orbit. Power delivered to the Mir bus was lower than desired as a consequence of the retrofitted power distribution cabling. The strong correlation of experimental and computational results further bolsters the confidence level of performance codes used in critical ISS electric power forecasting. In this paper, MCSA flight performance tests are described as well as the computational modeling behind the performance predictions.

  1. Research opportunities to advance solar energy utilization.

    PubMed

    Lewis, Nathan S

    2016-01-22

    Major developments, as well as remaining challenges and the associated research opportunities, are evaluated for three technologically distinct approaches to solar energy utilization: solar electricity, solar thermal, and solar fuels technologies. Much progress has been made, but research opportunities are still present for all approaches. Both evolutionary and revolutionary technology development, involving foundational research, applied research, learning by doing, demonstration projects, and deployment at scale will be needed to continue this technology-innovation ecosystem. Most of the approaches still offer the potential to provide much higher efficiencies, much lower costs, improved scalability, and new functionality, relative to the embodiments of solar energy-conversion systems that have been developed to date.

  2. Relaxing USOS Solar Array Constraints for Russian Vehicle Undocking

    NASA Technical Reports Server (NTRS)

    Menkin, Evgeny; Schrock, Mariusz; Schrock, Rita; Zaczek, Mariusz; Gomez, Susan; Lee, Roscoe; Bennet, George

    2011-01-01

    With the retirement of Space Shuttle cargo delivery capability and the ten year life extension of the International Space Station (ISS) more emphasis is being put on preservation of the service life of ISS critical components. Current restrictions on the United States Orbital Segment (USOS) Solar Array (SA) positioning during Russian Vehicle (RV) departure from ISS nadir and zenith ports cause SA to be positioned in the plume field of Service Module thrusters and lead to degradation of SAs as well as potential damage to Sun tracking Beta Gimbal Assemblies (BGA). These restrictions are imposed because of the single fault tolerant RV Motion Control System (MCS), which does not meet ISS Safety requirements for catastrophic hazards and dictates 16 degree Solar Array Rotary Joint position, which ensures that ISS and RV relative motion post separation, does lead to collision. The purpose of this paper is to describe a methodology and the analysis that was performed to determine relative motion trajectories of the ISS and separating RV for nominal and contingency cases. Analysis was performed in three phases that included ISS free drift prior to Visiting Vehicle separation, ISS and Visiting Vehicle relative motion analysis and clearance analysis. First, the ISS free drift analysis determined the worst case attitude and attitude rate excursions prior to RV separation based on a series of different configurations and mass properties. Next, the relative motion analysis calculated the separation trajectories while varying the initial conditions, such as docking mechanism performance, Visiting Vehicle MCS failure, departure port location, ISS attitude and attitude rates at the time of separation, etc. The analysis employed both orbital mechanics and rigid body rotation calculations while accounting for various atmospheric conditions and gravity gradient effects. The resulting relative motion trajectories were then used to determine the worst case separation envelopes during

  3. On Possible Arc Inception on Low Voltage Solar Array

    NASA Technical Reports Server (NTRS)

    Vayner, Boris

    2015-01-01

    Recent analysis of spacecraft failures during the period of 1990-2013 demonstrated clearly that electrostatic discharges caused more than 8 percent of all registered failures and anomalies, and comprised the most costly losses (25 percent) for operating companies and agencies. The electrostatic discharges on spacecraft surfaces are the results of differential charging above some critical (threshold) voltages. The mechanisms of differential charging are well known, and various methods have been developed to prevent a generation of significant electric fields in areas of triple junctions. For example, low bus voltages in Low Earth Orbit plasma environment and slightly conducting layer over cover-glass (ITO) in Geosynchronous Orbit surroundings are believed to be quite reliable measures to prevent discharges on respective surfaces. In most cases, the vulnerable elements of spacecraft (solar arrays, diode boards, etc.) go through comprehensive ground tests in vacuum chambers. However, tests articles contain the miniscule fragments of spacecraft components such as 10-30 solar cells of many thousands deployed on spacecraft in orbit. This is one reason why manufacturing defects may not be revealed in ground tests but expose themselves in arcing on array surface in space. The other reason for ineffectiveness of discharge preventive measures is aging of all materials in harsh orbital environments. The expected life time of modern spacecraft varies within the range of five-fifteen years, and thermal cycling, radiation damages, and mechanical stresses can result in surface erosion on conductive layers and microscopic cracks in cover-glass sheets and adhesive films. These possible damages may cause significant increases in local electric field strengths and subsequent discharges. The primary discharges may or may not be detrimental to spacecraft operation, but they can produce the necessary conditions for sustained arcs initiation. Multiple measures were developed to prevent

  4. On Possible Arc Inception on Low Voltage Solar Array

    NASA Technical Reports Server (NTRS)

    Vayner, Boris

    2015-01-01

    Recent analysis of spacecraft failures during the period of 1990-2013 demonstrated clearly that electrostatic discharges caused more than 8 of all registered failures and anomalies, and comprised the most costly losses (25) for operating companies and agencies. The electrostatic discharges on spacecraft surfaces are the results of differential charging above some critical (threshold) voltages. The mechanisms of differential charging are well known, and various methods have been developed to prevent a generation of significant electric fields in areas of triple junctions. For example, low bus voltages in Low Earth Orbit plasma environment and slightly conducting layer over coverglass (ITO) in Geosynchronous Orbit surroundings are believed to be quite reliable measures to prevent discharges on respective surfaces. In most cases, the vulnerable elements of spacecraft (solar arrays, diode boards, etc.) go through comprehensive ground tests in vacuum chambers. However, tests articles contain the miniscule fragments of spacecraft components such as 10-30 solar cells of many thousands deployed on spacecraft in orbit. This is one reason why manufacturing defects may not be revealed in ground tests but expose themselves in arcing on array surface in space. The other reason for ineffectiveness of discharge preventive measures is aging of all materials in harsh orbital environments. The expected life time of modern spacecraft varies within the range of five-fifteen years, and thermal cycling, radiation damages, and mechanical stresses can result in surface erosion on conductive layers and microscopic cracks in coverglass sheets and adhesive films. These possible damages may cause significant increases in local electric field strengths and subsequent discharges. The primary discharges may or may not be detrimental to spacecraft operation, but they can produce the necessary conditions for sustained arcs initiation. Multiple measures were developed to prevent sustained

  5. Simultaneous Solar Maximum Mission (SMM) and very large array observations of solar active regions

    NASA Technical Reports Server (NTRS)

    Lang, K. R.

    1986-01-01

    The research deals mainly with Very Large Array and Solar Maximum Mission observations of the ubiquitous coronal loops that dominate the structure of the low corona. As illustrated, the observations of thermal cyclotron lines at microwave wavelengths provide a powerful new method of accurately specifying the coronal magnetic field strength. Processes are delineated that trigger solar eruptions from coronal loops, including preburst heating and the magnetic interaction of coronal loops. Evidence for coherent burst mechanisms is provided for both the Sun and nearby stars, while other observations suggest the presence of currents that may amplify the coronal magnetic field to unexpectedly high levels. The existence is reported of a new class of compact, variable moving sources in regions of apparently weak photospheric field.

  6. Telescience operations with the solar array module plasma interaction experiment

    NASA Technical Reports Server (NTRS)

    Wald, Lawrence W.; Bibyk, Irene K.

    1995-01-01

    The Solar Array Module Plasma Interactions Experiment (SAMPIE) is a flight experiment that flew on the Space Shuttle Columbia (STS-62) in March 1994, as part of the OAST-2 mission. The overall objective of SAMPIE was to determine the adverse environmental interactions within the space plasma of low earth orbit (LEO) on modern solar cells and space power system materials which are artificially biased to high positive and negative direct current (DC) voltages. The two environmental interactions of interest included high voltage arcing from the samples to the space plasma and parasitic current losses. High voltage arcing can cause physical damage to power system materials and shorten expected hardware life. parasitic current losses can reduce power system efficiency because electric currents generated in a power system drain into the surrounding plasma via parasitic resistance. The flight electronics included two programmable high voltage DC power supplies to bias the experiment samples, instruments to measure the surrounding plasma environment in the STS cargo bay, and the on-board data acquisition system (DAS). The DAS provided in-flight experiment control, data storage, and communications through the Goddard Space Flight Center (GSFC) Hitchhiker flight avionics to the GSFC Payload Operations Control Center (POCC). The DAS and the SAMPIE POCC computer systems were designed for telescience operations; this paper will focus on the experiences of the SAMPIE team regarding telescience development and operations from the GSFC POCC during STS-62. The SAMPIE conceptual development, hardware design, and system verification testing were accomplished at the NASA Lewis Research Center (LeRC). SAMPIE was developed under the In-Space Technology Experiment Program (IN-STEP), which sponsors NASA, industry, and university flight experiments designed to enable and enhance space flight technology. The IN-STEP Program is sponsored by the Office of Space Access and Technology (OSAT).

  7. Standard for Solar Array Arc-Prevention in LEO - NASA 4005

    NASA Technical Reports Server (NTRS)

    Ferguson, Dale C.

    2006-01-01

    Spacecraft charging in Low Earth Orbit (LEO) is commonly caused by the high voltage (>55 V) solar array power system. Conversely, arcing on the solar arrays is an undesirable consequence of the spacecraft charging. The new NASA Low Earth Orbit Spacecraft Charging Design Standard and Information Handbook (NASA-4005) presents a standard and all the necessary background information to understand how to eliminate solar array arcing on LEO spacecraft in the design stage, before the spacecraft is built, and before costly retrofits are needed.

  8. Feasibility Study of Solar Dome Encapsulation of Photovoltaic Arrays

    NASA Technical Reports Server (NTRS)

    1978-01-01

    The technical and economic advantages of using air-supported plastic enclosures to protect flat plate photovoltaic arrays are described. Conceptual designs for a fixed, latitude-tilt array and a fully tracking array were defined. Detailed wind loads and strength analyses were performed for the fixed array. Detailed thermal and power output analyses provided array performance for typical seasonal and extreme temperature conditions. Costs of each design as used in a 200 MWe central power station were defined from manufacturing and material cost estimates. The capital cost and cost of energy for the enclosed fixed-tilt array were lower than for the enclosed tracking array. The enclosed fixed-tilt array capital investment was 38% less, and the levelized bus bar energy cost was 26% less than costs for a conventional, glass-encapsulated array design. The predicted energy cost for the enclosed fixed array was 79 mills/kW-h for direct current delivered to the power conditioning units.

  9. Commerical (terrestrial) and modified solar array design studies for low cost, low power space applications

    NASA Technical Reports Server (NTRS)

    Kolecki, J. C.; Riley, T. J.

    1980-01-01

    The suitability of commercial (terrestrial) solar arrays for use in low Earth orbit is examined. It is shown that commercial solar arrays degrade under thermal cycling because of material flexure, and that certain types of silicones used in the construction of these arrays outgas severely. Based on the results, modifications were made. The modified array retains the essential features of typical commercial arrays and can be easily built by commercial fabrication techniques at low cost. The modified array uses a metal tray for containment, but eliminates the high outgassing potting materials and glass cover sheets. Cells are individually mounted with an adhesive and individually covered with glass cover slips, or clear plastic tape. The modified array is found to withstand severe thermal cycling for long intervals of time.

  10. Solar energy harnessing in hexagonally arranged Si nanowire arrays and effects of array symmetry on optical characteristics.

    PubMed

    Li, Junshuai; Yu, HongYu; Li, Yali

    2012-05-17

    Investigation of solar energy harvesting in hexagonally arranged Si nanowire (NW) arrays is performed through optimizing the structural parameters, such as array periodicity (P), Si NW diameter (D) and length (L). The results demonstrate that there exist wide P and D/P 'windows' for the Si NW arrays, locating around 600 nm and 0.833 (i.e., D=500 nm), respectively, for achieving enhanced light absorption compared to their thin film counterparts with the same thickness, but with much less materials consumption. Calculation of the ultimate efficiency (UE) indicates that the light trapping capability is not monotonically increased with L, and that UE vibration is found when L is >1000 nm. Comparison of the light absorption spectra for hexagonally and squarely arranged Si NW arrays demonstrates that these two most widely employed array symmetries in practice have little impact on the light trapping capability.

  11. Process Technology and Advanced Concepts: Organic Solar Cells (Fact Sheet)

    SciTech Connect

    Not Available

    2011-06-01

    Capabilities fact sheet for the National Center for Photovoltaics: Process Technology and Advanced Concepts: Organic Solar Cell that includes scope, core competencies and capabilities, and contact/web information.

  12. Proceedings of the Flat-Plate Solar Array Project Research Forum on the design of flat-plate photovoltaic arrays for central stations

    SciTech Connect

    1983-01-01

    The Flat-Plate Solar Array Project, managed by the Jet Propulsion Laboratory for the US Department of Energy, has focused on advancing technologies relevant to the design and construction of megawatt-level central-station systems. Photovoltaic modules and arrays for flat-plate central-station or other large-scale electric power production facilities require the establishment of a technical base that resolves design issues and results in practical and cost-effective configurations. The Central Station Research Forum addressed design, qualification and maintenance issues related to central-station arrays derived from the engineering and operating experiences of early applications and parallel laboratory research activities. Technical issues were examined from the viewpoint of the utility engineer, architect-engineer and laboratory researcher. The forum included presentations on optimum source-circuit designs, module insulation design for high system voltages, array safety, structural interface design, measurements and array operation and maintenance. The Research Forum focused on current capabilities as well as design difficulties requiring additional technological thrusts and/or continued research emphasis. Session topic summaries highlighting major points during group discussions, identifying promising technical approaches or areas of future research, are presented.

  13. Integrated Phase Array Antenna/Solar Cell System for Flexible Access Communication (IA/SAC)

    NASA Technical Reports Server (NTRS)

    Clark, E. B.; Lee, R. Q.; Pal, A. T.; Wilt, D. M.; McElroy, B. D.; Mueller, C. H.

    2005-01-01

    This paper describes recent efforts to integrate advanced solar cells with printed planar antennas. Several previous attempts have been reported in the literature, but this effort is unique in several ways. It uses Gallium Arsenide (GaAs) multi-junction solar cell technology. The solar cells and antennas will be integrated onto a common GaAs substrate. When fully implemented, IA/SAC will be capable of dynamic beam steering. In addition, this program targets the X-band (8 - 12 GHz) and higher frequencies, as compared to the 2.2 - 2.9 GHz arrays targeted by other organizations. These higher operating frequencies enable a greater bandwidth and thus higher data transfer rates. The first phase of the effort involves the development of 2 x 2 cm GaAs Monolithically Integrated Modules (MIM) with integrated patch antennas on the opposite side of the substrate. Subsequent work will involve the design and development of devices having the GaAs MIMs and the antennas on the same side of the substrate. Results from the phase one efforts will be presented.

  14. Input Shaping to Reduce Solar Array Structural Vibrations

    NASA Technical Reports Server (NTRS)

    Doherty, Michael J.; Tolson, Robert J.

    1998-01-01

    Structural vibrations induced by actuators can be minimized using input shaping. Input shaping is a feedforward method in which actuator commands are convolved with shaping functions to yield a shaped set of commands. These commands are designed to perform the maneuver while minimizing the residual structural vibration. In this report, input shaping is extended to stepper motor actuators. As a demonstration, an input-shaping technique based on pole-zero cancellation was used to modify the Solar Array Drive Assembly (SADA) actuator commands for the Lewis satellite. A series of impulses were calculated as the ideal SADA output for vibration control. These impulses were then discretized for use by the SADA stepper motor actuator and simulated actuator outputs were used to calculate the structural response. The effectiveness of input shaping is limited by the accuracy of the knowledge of the modal frequencies. Assuming perfect knowledge resulted in significant vibration reduction. Errors of 10% in the modal frequencies caused notably higher levels of vibration. Controller robustness was improved by incorporating additional zeros in the shaping function. The additional zeros did not require increased performance from the actuator. Despite the identification errors, the resulting feedforward controller reduced residual vibrations to the level of the exactly modeled input shaper and well below the baseline cases. These results could be easily applied to many other vibration-sensitive applications involving stepper motor actuators.

  15. Static stability of the Space Station solar array FASTMast structure

    NASA Technical Reports Server (NTRS)

    Shaker, John F.; Acquaviva, Thomas H.

    1995-01-01

    The combined loads test of the 3-Bay FASTMast marks the end of the Lewis Research Center (LeRC) effort to characterize the behavior of the principal Space Station solar array support structure. The primary objective of this test and analysis effort was to develop a method to predict structural stability failure modes under flight-like applied loads. Included at the beginning of this report is a brief historical perspective of the hardware design development and FASTMast structural stability problem evolution. Once an understanding of the solution process has been established, test and analysis details are presented and related to the postulated failure theories. The combined load test series subjected the structure to a combination of transverse, moment, and torsion loads similar to that expected in the service environment. Nonlinear finite element (FE) models were developed and large displacement analyses were performed to support the test effort and failure mode predictions. Details of the test configuration as well as test and analysis results are presented. The results were then critiqued to establish valid and successful support of the failure mode assessments. Finally, study conclusions are drawn and recommendations for safe operation of the FASTMast structure are presented for consideration.

  16. Flat-plate solar array progress and plans

    NASA Technical Reports Server (NTRS)

    Callaghan, W. T.; Henry, P. K.

    1984-01-01

    The Flat-Plate Solar Array Project (FSA), sponsored by the U.S. Department of Energy (DOE) and managed by the Jet Propulsion Laboratory (JPL), has achieved progress in a broad range of technical activities since that reported at the Fourth European Communities Conference. A particularly important analysis has been completed recently which confirms the adoption into practice by the U.S. Photovoltaic (PV Industry, of all the low-cost module technology elements proposed at the 16th Project Integration Meeting for a $2.80/Wp (1980 U.S. Dollars) design approach in the fall of 1980. This work presents along with a projection, using the same techniques, for what is believed to be a very credible ribbon-based module design for less that $0.55/Wp (1980 U.S. Dollars). Other areas to be reported upon include low-cost Si feedstock refinement; ribbon growth; process sequence development for cells; environmental isolation; engineering science investigations; and module testing progress.

  17. The automated array assembly task of the low-cost silicon solar array project, phase 2

    NASA Technical Reports Server (NTRS)

    Coleman, M. G.; Pryor, R. A.; Sparks, T. G.; Legge, R.; Saltzman, D. L.

    1980-01-01

    Several specific processing steps as part of a total process sequence for manufacturing silicon solar cells were studied. Ion implantation was identified as the preferred process step for impurity doping. Unanalyzed beam ion implantation was shown to have major cost advantages over analyzed beam implantation. Further, high quality cells were fabricated using a high current unanalyzed beam. Mechanically masked plasma patterning of silicon nitride was shown to be capable of forming fine lines on silicon surfaces with spacings between mask and substrate as great as 250 micrometers. Extensive work was performed on advances in plated metallization. The need for the thick electroless palladium layer was eliminated. Further, copper was successfully utilized as a conductor layer utilizing nickel as a barrier to copper diffusion into the silicon. Plasma etching of silicon for texturing and saw damage removal was shown technically feasible but not cost effective compared to wet chemical etching techniques.

  18. The arcing rate for a High Voltage Solar Array - Theory, experiment and predictions

    NASA Technical Reports Server (NTRS)

    Hastings, Daniel E.; Cho, Mengu; Kuninaka, Hitoshi

    1992-01-01

    All solar arrays have biased surfaces which can be exposed to the space environment. It has been observed that when the array bias is less than a few hundred volts negative then the exposed conductive surfaces may undergo arcing in the space plasma. A theory for arcing is developed on these high voltage solar arrays which ascribes the arcing to electric field runaway at the interface of the plasma, conductor and solar cell dielectric. Experiments were conducted in the laboratory for the High Voltage Solar Array (HVSA) experiment which will fly on the Japanese Space Flyer Unit (SFU) in 1994. The theory was compared in detail to the experiment and shown to give a reasonable explanation for the data. The combined theory and ground experiments were then used to develop predictions for the SFU flight.

  19. Arcing rates for High Voltage Solar Arrays - Theory, experiment, and predictions

    NASA Technical Reports Server (NTRS)

    Hastings, Daniel E.; Cho, Mengu; Kuninaka, Hitoshi

    1992-01-01

    All solar arrays have biased surfaces that can be exposed to the space environment. It has been observed that when the array bias is less than a few hundred volts negative, then the exposed conductive surfaces may undergo arcing in the space plasma. A theory for arcing is developed on these high voltage solar arrays that ascribes the arcing to electric field runaway at the interface of the plasma, conductor, and solar cell dielectric. Experiments were conducted in the laboratory for the High Voltage Solar Array experiment that will fly on the Japanese Space Flyer Unit (SFU) in 1994. The theory was compared in detail with the experiment and shown to give a reasonable explanation for the data. The combined theory and ground experiments were then used to develop predictions for the SFU flight.

  20. Method of making silicon solar cell array. [and mounting on flexible substrate

    NASA Technical Reports Server (NTRS)

    Forestieri, A. F.; Broder, J. D.; Bernatowicz, D. T. (Inventor)

    1973-01-01

    A heat sealable transparent plastic film, such as a flourinated ethylene propylene copolymer, is used both as a cover material and as an adhesive for mounting a solar cell array to a flexible substrate.

  1. Advances in Solar Radiometry and Metrology

    SciTech Connect

    Myers, D.; Andreas, A.; Reda, I.; Gotseff, P.; Wilcox, S.; Stoffel, T.; Anderberg, M.

    2005-01-01

    The Solar Radiometry and Metrology task at the National Renewable Energy Laboratory (NREL) provides traceable optical radiometric calibrations and measurements to photovoltaic (PV) researchers and the PV industry. Traceability of NREL solar radiometer calibrations to the World Radiometric Reference (WRR) was accomplished during the NREL Pyrheliometer Comparison in October 2003. The task has calibrated 10 spectral and more than 180 broadband radiometers for solar measurements. Other accomplishments include characterization of pyranometer thermal offset errors with laboratory and spectral modeling tools; developing a simple scheme to correct pyranometer data for known responsivity variations; and measuring detailed spectral distributions of the NREL High Intensity Pulsed Solar Simulator (HIPSS) as a function of lamp voltage and time. The optical metrology functions support the NREL Measurement and Characterization Task effort for ISO 17025 accreditation of NREL Solar Reference Cell Calibrations. Optical metrology functions have been integrated into the NREL quality system and audited for ISO17025 compliance.

  2. Technical evaluation of Solar Cells, Inc., CdTe module and array at NREL

    SciTech Connect

    Kroposki, B.; Strand, T.; Hansen, R.; Powell, R.; Sasala, R.

    1996-05-01

    The Engineering and Technology Validation Team at the National Renewable Energy Laboratory (NREL) conducts in-situ technical evaluations of polycrystalline thin-film photovoltaic (PV) modules and arrays. This paper focuses on the technical evaluation of Solar Cells, Inc., (SCI) cadmium telluride (CdTe) module and array performance by attempting to correlate individual module and array performance. This is done by examining the performance and stability of the modules and array over a period of more than one year. Temperature coefficients for module and array parameters (P{sub max}, V{sub oc}, V{sub max}, I{sub sc}, I{sub max}) are also calculated.

  3. Classical and adaptive control algorithms for the solar array pointing system of the Space Station Freedom

    NASA Technical Reports Server (NTRS)

    Ianculescu, G. D.; Klop, J. J.

    1992-01-01

    Classical and adaptive control algorithms for the solar array pointing system of the Space Station Freedom are designed using a continuous rigid body model of the solar array gimbal assembly containing both linear and nonlinear dynamics due to various friction components. The robustness of the design solution is examined by performing a series of sensitivity analysis studies. Adaptive control strategies are examined in order to compensate for the unfavorable effect of static nonlinearities, such as dead-zone uncertainties.

  4. HSPICE modelling of a solar array circuit controlled by a fet switch

    NASA Technical Reports Server (NTRS)

    Cox, Deanna D.; Natarajan, T.; Day, John

    1987-01-01

    This paper presents a method of modeling a solar array circuit controlled by a hexfet switch on HSPICE. HSPICE models are developed for the solar array current voltage (IV) characteristic and the IRF150 hexfet. Computer simulations are made to verify rate of current change at the load. The equivalent LC circuit for the same current control is modeled to show savings in weight and power in choosing the fet switch over an LC circuit.

  5. Prediction of gear wear for the estimation of solar array drive dynamic behavior

    NASA Astrophysics Data System (ADS)

    Shatikhin, V. Ye.; Semenov, L. P.; Khoroshilov, V. S.; Popel', V. M.; Kostenko, G. A.

    We describe the dynamic behavior of the solar array gears installed on the long-life spacecraft. Impact of the time-dependant deterioration of gearing accuracy caused by the operational wear on the driver's dynamic performance is analysed. The necessity of taking into account the time-dependant deterioration of the gearing accuracy for the estimation of the solar array drive dynamic performance is justified.

  6. Optimal Space Station solar array gimbal angle determination via radial basis function neural networks

    NASA Technical Reports Server (NTRS)

    Clancy, Daniel J.; Oezguener, Uemit; Graham, Ronald E.

    1994-01-01

    The potential for excessive plume impingement loads on Space Station Freedom solar arrays, caused by jet firings from an approaching Space Shuttle, is addressed. An artificial neural network is designed to determine commanded solar array beta gimbal angle for minimum plume loads. The commanded angle would be determined dynamically. The network design proposed involves radial basis functions as activation functions. Design, development, and simulation of this network design are discussed.

  7. Plasma Interactions with High Voltage Solar Arrays for a Direct Drive Hall Effect Thruster System

    NASA Technical Reports Server (NTRS)

    Schneider, T.; Horvater, M. A.; Vaughn, J.; Carruth, M. R.; Jongeward, G. A.; Mikellides, I. G.

    2003-01-01

    The Environmental Effects Group of NASA s Marshall Space Flight Center (MSFC) is conducting research into the effects of plasma interaction with high voltage solar arrays. These high voltage solar arrays are being developed for a direct drive Hall Effect Thruster propulsion system. A direct drive system configuration will reduce power system mass by eliminating a conventional power-processing unit. The Environmental Effects Group has configured two large vacuum chambers to test different high-voltage array concepts in a plasma environment. Three types of solar arrays have so far been tested, an International Space Station (ISS) planar array, a Tecstar planar array, and a Tecstar solar concentrator array. The plasma environment was generated using a hollow cathode plasma source, which yielded densities between 10(exp 6) - 10(exp 7) per cubic centimeter and electron temperatures of 0.5-1 eV. Each array was positioned in this plasma and biased in the -500 to + 500 volt range. The current collection was monitored continuously. In addition, the characteristics of arcing, snap over, and other features, were recorded. Analysis of the array performance indicates a time dependence associated with the current collection as well as a tendency for "conditioning" over a large number of runs. Mitigation strategies, to reduce parasitic current collection, as well as arcing, include changing cover-glass geometry and layout as well as shielding the solar cell edges. High voltage performance data for each of the solar array types tested will be presented. In addition, data will be provided to indicate the effectiveness of the mitigation techniques.

  8. Electromagnetic resonances of solar-selective absorbers with nanoparticle arrays embedded in a dielectric layer

    NASA Astrophysics Data System (ADS)

    Sakurai, Atsushi; Kawamata, Tomoaki

    2016-11-01

    We numerically investigate a solar-selective absorber with tungsten core-shell nanoparticle arrays embedded in an SiO2 layer. The 3D full-wave finite-difference time-domain (FDTD) simulations are performed to investigate the geometric effects of different types of solar-selective absorbers. Consequently, broadband light absorption was achieved with either a tungsten nanoparticle array or a tungsten core-shell nanoparticle array because of the strong electric field enhancement in the gap between the core nanoparticles. The solar performance of the proposed structure is shown for high-efficiency solar light absorption. This study enhances understanding of the light absorption mechanism of metallic nanoparticle/dielectric composite and facilitates the design of high-efficiency solar-selective absorbers.

  9. Simultaneous Solar Maximum Mission (SMM) and Very Large Array (VLA) observations of solar active regions

    NASA Technical Reports Server (NTRS)

    Willson, Robert F.

    1991-01-01

    Very Large Array observations at 20 cm wavelength can detect the hot coronal plasma previously observed at soft x ray wavelengths. Thermal cyclotron line emission was detected at the apex of coronal loops where the magnetic field strength is relatively constant. Detailed comparison of simultaneous Solar Maximum Mission (SMM) Satellite and VLA data indicate that physical parameters such as electron temperature, electron density, and magnetic field strength can be obtained, but that some coronal loops remain invisible in either spectral domain. The unprecedent spatial resolution of the VLA at 20 cm wavelength showed that the precursor, impulsive, and post-flare components of solar bursts originate in nearby, but separate loops or systems of loops.. In some cases preburst heating and magnetic changes are observed from loops tens of minutes prior to the impulsive phase. Comparisons with soft x ray images and spectra and with hard x ray data specify the magnetic field strength and emission mechanism of flaring coronal loops. At the longer 91 cm wavelength, the VLA detected extensive emission interpreted as a hot 10(exp 5) K interface between cool, dense H alpha filaments and the surrounding hotter, rarefield corona. Observations at 91 cm also provide evidence for time-correlated bursts in active regions on opposite sides of the solar equator; they are attributed to flare triggering by relativistic particles that move along large-scale, otherwise-invisible, magnetic conduits that link active regions in opposite hemispheres of the Sun.

  10. Advanced research in solar-energy storage

    SciTech Connect

    Luft, W.

    1983-01-01

    The Solar Energy Storage Program at the Solar Energy Research Institute is reviewed. The program provides research, systems analyses, and economic assessments of thermal and thermochemical energy storage and transport. Current activities include experimental research into very high temperature (above 800/sup 0/C) thermal energy storage and assessment of novel thermochemical energy storage and transport systems. The applications for such high-temperature storage are thermochemical processes, solar thermal-electric power generation, cogeneration of heat and electricity, industrial process heat, and thermally regenerative electrochemical systems. The research results for five high-temperature thermal energy storage technologies and two thermochemical systems are described.

  11. Assessment of SEPS solar array technology for orbital service module application

    NASA Technical Reports Server (NTRS)

    1978-01-01

    Work performed in the following assessment areas on the SEPS solar array is reported: (1) requirements definition, (2) electrical design evaluation, (3) mechanical design evaluation, and (4) design modification analysis. General overall assessment conclusions are summarized. There are no known serious design limitations involved in the implementation of the recommended design modifications. A section of orbiter and array engineering drawings is included.

  12. Validation Report for the EO-1 Lightweight Flexible Solar Array Experiment

    NASA Technical Reports Server (NTRS)

    Carpenter, Bernie; Lyons, John; Day, John (Technical Monitor)

    2001-01-01

    The controlled deployment of the Lightweight Flexible Solar Array (LFSA) experiment using the shape memory alloy release and deployment system has been demonstrated. Work remains to be done in increasing the efficiency of Copper Indium Diselinide (CIS) terminations to the flexible harness that carries current from the array to the I-V measurement electronics.

  13. Microlens array induced light absorption enhancement in polymer solar cells

    SciTech Connect

    Chen, Yuqing; Elshobaki, Moneim; Ye, Zhuo; Park, Joong-Mok; Noack, Max A.; Ho, Kai-Ming; Chaudhary, Sumit

    2013-01-24

    Over the last decade, polymer solar cells (PSCs) have attracted a lot of attention and highest power conversion efficiencies (PCE) are now close to 10%. Here we employ an optical structure – the microlens array (MLA) – to increase light absorption inside the active layer, and PCE of PSCs increased even for optimized devices. Normal incident light rays are refracted at the MLA and travel longer optical paths inside the active layers. Two PSC systems – poly(3-hexylthiophene-2,5-diyl):(6,6)-phenyl C61 butyric acid methyl ester (P3HT:PCBM) and poly[[9-(1-octylnonyl)-9H-carbazole-2,7-diyl]-2,5-thiophenediyl-2,1,3-benzothiadiazole-4,7-diyl-2,5-thiophenediyl]:(6,6)-phenyl C71 butyric acid methyl ester (PCDTBT:PC70BM) – were investigated. In the P3HT:PCBM system, MLA increased the absorption, absolute external quantum efficiency, and the PCE of an optimized device by [similar]4.3%. In the PCDTBT:PC70BM system, MLA increased the absorption, absolute external quantum efficiency, and PCE by more than 10%. In addition, simulations incorporating optical parameters of all structural layers were performed and they support the enhancement of absorption in the active layer with the assistance of MLA. Our results show that utilizing MLA is an effective strategy to further increase light absorption in PSCs, in which optical losses account for [similar]40% of total losses. MLA also does not pose materials processing challenges to the active layers since it is on the other side of the transparent substrate.

  14. Microlens array induced light absorption enhancement in polymer solar cells.

    PubMed

    Chen, Yuqing; Elshobaki, Moneim; Ye, Zhuo; Park, Joong-Mok; Noack, Max A; Ho, Kai-Ming; Chaudhary, Sumit

    2013-03-28

    Over the last decade, polymer solar cells (PSCs) have attracted a lot of attention and highest power conversion efficiencies (PCE) are now close to 10%. Here we employ an optical structure - the microlens array (MLA) - to increase light absorption inside the active layer, and PCE of PSCs increased even for optimized devices. Normal incident light rays are refracted at the MLA and travel longer optical paths inside the active layers. Two PSC systems - poly(3-hexylthiophene-2,5-diyl):(6,6)-phenyl C61 butyric acid methyl ester (P3HT:PCBM) and poly[[9-(1-octylnonyl)-9H-carbazole-2,7-diyl]-2,5-thiophenediyl-2,1,3-benzothiadiazole-4,7-diyl-2,5-thiophenediyl]:(6,6)-phenyl C71 butyric acid methyl ester (PCDTBT:PC70BM) - were investigated. In the P3HT:PCBM system, MLA increased the absorption, absolute external quantum efficiency, and the PCE of an optimized device by ∼4.3%. In the PCDTBT:PC70BM system, MLA increased the absorption, absolute external quantum efficiency, and PCE by more than 10%. In addition, simulations incorporating optical parameters of all structural layers were performed and they support the enhancement of absorption in the active layer with the assistance of MLA. Our results show that utilizing MLA is an effective strategy to further increase light absorption in PSCs, in which optical losses account for ∼40% of total losses. MLA also does not pose materials processing challenges to the active layers since it is on the other side of the transparent substrate. PMID:23407762

  15. Design, performance investigation and delivery of a miniaturized Cassegrainian concentrator solar array

    NASA Technical Reports Server (NTRS)

    Patterson, R. E.

    1985-01-01

    A miniaturized Cassegrainian concentrator (MCC) solar array concept is being developed with the objective of significantly reducing the recurring cost of multikilowatt solar arrays. The desired cost reduction is obtained as a result of using very small high efficiency solar cells in conjunction with low-cost optics. In the MCC single element concept and panel concept, incident solar radiation is reflected from a primary parabolic reflector to a secondary hyperbolic reflector and finally to a 4-millimetr diameter solar cell. A light catcher cone is used to improve off-axis performance. An element is approximately 13-millimeters thick which permits efficient launch stowage of the concentrator system panels without complex optical component deployments or retractions. The MCC elements are packed in bays within graphite epoxy frames and are electrically connected into appropriate series-parallel circuits. A MCC single element with a 21 sq cm entrance aperture and a 20 percent efficient, 0.25 sq cm gallium arsenide solar cell has the same power output as 30-sq cm of 11-percent efficiency (at 68 C) silicon solar cells. The MCC concept provides the potential for a significant reduction in array cost due to a 99 percent reduction in required cell area and a 30 percent reduction in array area relative to planar array of equivalent power.

  16. Geospace Science from Ground-based Magnetometer Arrays: Advances in Sensors, Data Collection, and Data Integration

    NASA Astrophysics Data System (ADS)

    Mann, Ian; Chi, Peter

    2016-07-01

    Networks of ground-based magnetometers now provide the basis for the diagnosis of magnetic disturbances associated with solar wind-magnetosphere-ionosphere coupling on a truly global scale. Advances in sensor and digitisation technologies offer increases in sensitivity in fluxgate, induction coil, and new micro-sensor technologies - including the promise of hybrid sensors. Similarly, advances in remote connectivity provide the capacity for truly real-time monitoring of global dynamics at cadences sufficient for monitoring and in many cases resolving system level spatio-temporal ambiguities especially in combination with conjugate satellite measurements. A wide variety of the plasmaphysical processes active in driving geospace dynamics can be monitored based on the response of the electrical current system, including those associated with changes in global convection, magnetospheric substorms and nightside tail flows, as well as due to solar wind changes in both dynamic pressure and in response to rotations of the direction of the IMF. Significantly, any changes to the dynamical system must be communicated by the propagation of long-period Alfven and/or compressional waves. These wave populations hence provide diagnostics for not only the energy transport by the wave fields themselves, but also provide a mechanism for diagnosing the structure of the background plasma medium through which the waves propagate. Ultra-low frequency (ULF) waves are especially significant in offering a monitor for mass density profiles, often invisible to particle detectors because of their very low energy, through the application of a variety of magneto-seismology and cross-phase techniques. Renewed scientific interest in the plasma waves associated with near-Earth substorm dynamics, including magnetosphere-ionosphere coupling at substorm onset and their relation to magnetotail flows, as well the importance of global scale ultra-low frequency waves for the energisation, transport

  17. Observation and Modeling of the Solar Transition Region. 1; Multi-Spectral Solar Telescope Array Observations

    NASA Technical Reports Server (NTRS)

    Oluseyi, Hakeem M.; Walker, A. B. C., II; Porter, Jason; Hoover, Richard B.; Barbee, Troy W., Jr.

    1999-01-01

    We report on observations of the solar atmosphere in several extreme-ultraviolet and far-ultraviolet bandpasses obtained by the Multi-Spectral Solar Telescope Array, a rocket-borne spectroheliograph, on flights in 1987, 1991, and 1994, spanning the last solar maximum. Quiet-Sun emission observed in the 171-175 Angstrom bandpass, which includes lines of O v, O VI, Fe IX, and Fe X, has been analyzed to test models of the temperatures and geometries of the structures responsible for this emission. Analyses of intensity variations above the solar limb reveal scale heights consistent with a quiet-Sun plasma temperature of 500,000 less than or equal to T (sub e) less than or equal to 800,000 K. The structures responsible for the quiet-Sun EUV emission are modeled as small quasi-static loops. We submit our models to several tests. We compare the emission our models would produce in the bandpass of our telescope to the emission we have observed. We find that the emission predicted by loop models with maximum temperatures between 700,000 and 900,000 K are consistent with our observations. We also compare the absolute flux predicted by our models in a typical upper transition region line to the flux measured by previous observers. Finally, we present a preliminary comparison of the predictions of our models with diagnostic spectral line ratios from previous observers. Intensity modulations in the quiet Sun are observed to occur on a scale comparable to the supergranular scale. We discuss the implications that a distribution of loops of the type we model here would have for heating the local network at the loops' footpoints.

  18. Effect of parasitic plasma currents on solar-array power output

    NASA Technical Reports Server (NTRS)

    Domitz, S.; Kolecki, J. C.

    1979-01-01

    Solar-array voltage-current curves are calculated by assuming the existence of parasitic loads that consist of local currents of charged particles collected by the array. Three cases of interest are calculated to demonstrate how the distribution and magnitude of parasitic currents affect output. Solar array performance degradation became significant when the total parasitic current plus the load current exceeded the short-circuit current. Approximate graphical methods were useful for many applications. Power loss, which was calculated by summing the product of parasitic current and the local potential, underestimated the loss in maximum power.

  19. Surface voltage gradient role in high voltage solar array-plasma interaction: Center Director's discretionary fund

    NASA Technical Reports Server (NTRS)

    Carruth, M. R., Jr.

    1985-01-01

    A large amount of experimental and analytical effort has been directed toward understanding the plasma sheath growth and discharge phenomena which lead to high voltage solar array-space plasma interactions. An important question which has not been addressed is how the surface voltage gradient on such an array may affect these interactions. The results of this study indicate that under certain conditions, the voltage gradient should be taken into account when evaluating the effect on a solar array operating in a plasma environment.

  20. Terra Flexible Blanket Solar Array Deployment, On-Orbit Performance and Future Applications

    NASA Technical Reports Server (NTRS)

    Kurland, Richard; Schurig, Hans; Rosenfeld, Mark; Herriage, Michael; Gaddy, Edward; Keys, Denney; Faust, Carl; Andiario, William; Kurtz, Michelle; Moyer, Eric; Day, John H. (Technical Monitor)

    2000-01-01

    The Terra spacecraft (formerly identified as EOS AM1) is the flagship in a planned series of NASA/GSFC (Goddard Space Flight Center) Earth observing system satellites designed to provide information on the health of the Earth's land, oceans, air, ice, and life as a total ecological global system. It has been successfully performing its mission since a late-December 1999 launch into a 705 km polar orbit. The spacecraft is powered by a single wing, flexible blanket array using single junction (SJ) gallium arsenide/germanium (GaAs/Ge) solar cells sized to provide five year end-of-life (EOL) power of greater than 5000 watts at 127 volts. It is currently the highest voltage and power operational flexible blanket array with GaAs/Ge cells. This paper briefly describes the wing design as a basis for discussing the operation of the electronics and mechanisms used to achieve successful on-orbit deployment. Its orbital electrical performance to date will be presented and compared to analytical predictions based on ground qualification testing. The paper concludes with a brief section on future applications and performance trends using advanced multi-junction cells and weight-efficient mechanical components. A viewgraph presentation is attached that outlines the same information as the paper and includes more images of the Terra Spacecraft and its components.

  1. Terra Flexible Blanket Solar Array Deployment, On-Orbit Performance and Future Applications

    NASA Technical Reports Server (NTRS)

    Kurland, Richard; Schurig, Hans; Rosenfeld, Mark; Herriage, Michael; Gaddy, Edward; Keys, Denney; Faust, Carl; Andiario, William; Kurtz, Michelle; Moyer, Eric; Day, John H. (Technical Monitor)

    2000-01-01

    The Terra spacecraft (formerly identified as EOS AM1) is the flagship in a planned series of NASA/GSFC (Goddard Space Flight Center) Earth observing system satellites designed to provide information on the health of the Earth's land, oceans, air, ice, and life as a total ecological global system. It has been successfully performing its mission since a late-December 1999 launch into a 705 km polar orbit. The spacecraft is powered by a single wing, flexible blanket array using single junction (SJ) gallium arsenide/germanium (GaAs/Ge) solar cells sized to provide five year end-of-life (EOL) power of greater than 5000 watts at 127 volts. It is currently the highest voltage and power operational flexible blanket array with GaAs/Ge cells. This paper briefly describes the wing design as a basis for discussing the operation of the electronics and mechanisms used to achieve successful on-orbit deployment. Its orbital electrical performance to date will be presented and compared to analytical predictions based on ground qualification testing. The paper concludes with a brief section on future applications and performance trends using advanced multi-junction cells and weight-efficient mechanical components.

  2. High-performance deployable structures for the support of high-concentration ratio solar array modules

    NASA Technical Reports Server (NTRS)

    Mobrem, M.

    1985-01-01

    A study conducted on high-performance deployable structures for the support of high-concentration ratio solar array modules is discussed. Serious consideration is being given to the use of high-concentration ratio solar array modules or applications such as space stations. These concentrator solar array designs offer the potential of reduced cost, reduced electrical complexity, higher power per unit area, and improved survivability. Arrays of concentrators, such as the miniaturized Cassegrainian concentrator modules, present a serious challenge to the structural design because their mass per unit area (5.7 kg/square meters) is higher than that of flexible solar array blankets, and the requirement for accurate orientation towards the Sun (plus or minus 0.5 degree) requires structures with improved accuracy potentials. In addition, use on a space station requires relatively high structural natural frequencies to avoid deleterious interactions with control systems and other large structural components. The objective here is to identify and evaluate conceptual designs of structures suitable for deploying and accurately supporting high-concentration ratio solar array modules.

  3. Lightweight Integrated Solar Array and Transceiver. [Improving Electrical Power and Communication Capabilities in Small Spacecraft

    NASA Technical Reports Server (NTRS)

    Carr, John; Martinez, Andres; Petro, Andrew

    2015-01-01

    The Lightweight Integrated Solar Array and Transceiver (LISA-T) project will leverage several existing and on-going efforts at Marshall Space Flight Center (MSFC) for the design, development, fabrication, and test of a launch stowed, orbit deployed structure on which thin-film photovoltaics for power generation and antenna elements for communication, are embedded. Photovoltaics is a method for converting solar energy into electricity using semiconductor materials. The system will provide higher power generation with a lower mass, smaller stowage volume, and lower cost than the state of the art solar arrays, while simultaneously enabling deployable antenna concepts.

  4. Preliminary results from the flight of the Solar Array Module Plasma Interactions Experiment (SAMPIE)

    NASA Technical Reports Server (NTRS)

    Ferguson, Dale C.; Hillard, G. Barry

    1994-01-01

    SAMPIE, the Solar Array Module Plasma Interactions Experiment, flew in the Space Shuttle Columbia payload bay as part of the Office of Aeronautics and Space Technology-2 (OAST-2) mission on STS-62, March, 1994. SAMPIE biased samples of solar arrays and space power materials to varying potentials with respect to the surrounding space plasma, and recorded the plasma currents collected and the arcs which occurred, along with a set of plasma diagnostics data. A large set of high quality data was obtained on the behavior of solar arrays and space power materials in the space environment. This paper is the first report on the data SAMPIE telemetered to the ground during the mission. It will be seen that the flight data promise to help determine arcing thresholds, snapover potentials, and floating potentials for arrays and spacecraft in LEO.

  5. Preliminary Results from the Flight of the Solar Array Module Plasma Interactions Experiment (SAMPIE)

    NASA Technical Reports Server (NTRS)

    Ferguson, Dale C.; Hillard, G. Barry

    1994-01-01

    SAMPIE, the Solar Array Module Plasma Interactions Experiment, flew in the Space Shuttle Columbia payload bay as part of the OAST-2 mission on STS-62, March, 1994. SAMPIE biased samples of solar arrays and space power materials to varying potentials with respect to the surrounding space plasma, and recorded the plasma currents collected and the arcs which occurred, along with a set of plasma diagnostics data. A large set of high quality data was obtained on the behavior of solar arrays and space power materials in the space environment. This paper is the first report on the data SAMPIE telemetered to the ground during the mission. It will be seen that the flight data promise to help determine arcing thresholds, snapover potentials and floating potentials for arrays and spacecraft in LEO.

  6. Concept Definition Study for In-Space Structural Characterization of a Lightweight Solar Array

    NASA Technical Reports Server (NTRS)

    Woods-Vedeler, Jessica A.; Pappa, Richard S.; Jones, Thomas W.; Spellman, Regina; Scott, Willis; Mockensturm, Eric M.; Liddle, Donn; Oshel, Ed; Snyder, Michael

    2002-01-01

    A Concept Definition Study (CDS) was conducted to develop a proposed "Lightweight High-Voltage Stretched-Lens Concentrator Solar Array Experiment" under NASA's New Millennium Program Space Technology-6 (NMP ST-6) activity. As part of a multi-organizational team, NASA Langley Research Center's role in this proposed experiment was to lead Structural Characterization of the solar array during the flight experiment. In support of this role, NASA LaRC participated in the CDS to de.ne an experiment for static, dynamic, and deployment characterization of the array. In this study, NASA LaRC traded state-of-the-art measurement approaches appropriate for an in-space, STS-based flight experiment, provided initial analysis and testing of the lightweight solar array and lens elements, performed a lighting and photogrammetric simulation in conjunction with JSC, and produced an experiment concept definition to meet structural characterization requirements.

  7. Brayton cycle solarized advanced gas turbine

    NASA Technical Reports Server (NTRS)

    1986-01-01

    Described is the development of a Brayton Engine/Generator Set for solar thermal to electrical power conversion, authorized under DOE/NASA Contract DEN3-181. The objective was to design, fabricate, assemble, and test a small, hybrid, 20-kW Brayton-engine-powered generator set. The latter, called a power conversion assembly (PCA), is designed to operate with solar energy obtained from a parobolic dish concentrator, 11 meters in diameter, or with fossil energy supplied by burning fuels in a combustor, or by a combination of both (hybrid model). The CPA consists of the Brayton cycle engine, a solar collector, a belt-driven 20-kW generator, and the necessary control systems for automatic operation in solar-only, fuel-only, and hybrid modes to supply electrical power to a utility grid. The original configuration of the generator set used the GTEC Model GTP36-51 gas turbine engine for the PCA prime mover. However, subsequent development of the GTEC Model AGT101 led to its selection as the powersource for the PCA. Performance characteristics of the latter, thermally coupled to a solar collector for operation in the solar mode, are presented. The PCA was successfully demonstrated in the fuel-only mode at the GTEC Phoenix, Arizona, facilities prior to its shipment to Sandia National Laboratory in Albuquerque, New Mexico, for installation and testing on a test bed concentractor (parabolic dish). Considerations relative to Brayton-engine development using the all-ceramic AGT101 when it becomes available, which would satisfy the DOE heat engine efficiency goal of 35 to 41 percent, are also discussed in the report.

  8. LDEF (Prelaunch), AO171 : Solar-Array-Materials Passive LDEF Experiment, Tray A08

    NASA Technical Reports Server (NTRS)

    1984-01-01

    LDEF (Prelaunch), AO171 : Solar-Array-Materials Passive LDEF Experiment, Tray A08 EL-1994-00044 LDEF (Prelaunch), AO171 : Solar-Array-Materials Passive LDEF Experiment, Tray A08 The prelaunch photograph was taken in SAEF II at KSC prior to installation of the Solar Array Materials Passive LDEF Experiment (SAMPLE) on the LDEF. Six (6) plates of passive components, provided by various experiment organizations and designated plate I thru plate VI, are shown mounted in a three (3) inch deep LDEF peripheral tray. All six plates are aluminum and attach to the LDEF experiment tray with non-magnetic stainless steel fasteners. Plate I, located in the upper right corner, consist of a combination of solar cells with and without covers, solar cell modules and solar arrays assembled on the baseplate. Plate II in the upper center section, has twenty seven (27) composite samples, carbon fiber and glass fiber, mounted on the baseplate. Plate III, in the upper left corner, consist mostly of metallized and thin polymeric films (Kapton, Mylar, TEFLON® , white Tedlar,etc.). Plate IV located in the lower right corner consist of metals and coatings mounted in an aluminum baseplate and covered with a thin aluminum coverplate that partially mask the specimen. Plate V contained thermal plastics and structural film configured into tensile and shear specimen. Plate VI was populated with solar cells and associate components (covers, encapsulants,adhesives, etc.).

  9. Reverse bias protected solar array with integrated bypass battery

    NASA Technical Reports Server (NTRS)

    Landis, Geoffrey A (Inventor)

    2012-01-01

    A method for protecting the photovoltaic cells in a photovoltaic (PV) array from reverse bias damage by utilizing a rechargeable battery for bypassing current from a shaded photovoltaic cell or group of cells, avoiding the need for a bypass diode. Further, the method mitigates the voltage degradation of a PV array caused by shaded cells.

  10. Phase 1 of the automated array assembly task of the low cost silicon solar array project

    NASA Technical Reports Server (NTRS)

    Coleman, M. G.; Pryor, R. A.; Grenon, L. A.; Lesk, I. A.

    1977-01-01

    The state of technology readiness for the automated production of solar cells and modules is reviewed. Individual process steps and process sequences for making solar cells and modules were evaluated both technically and economically. High efficiency with a suggested cell goal of 15% was stressed. It is concluded that the technology exists to manufacture solar cells which will meet program goals.

  11. Recent technological advances in thin film solar cells

    SciTech Connect

    Ullal, H.S.; Zwelbel, K.; Surek, T.

    1990-03-01

    High-efficiency, low-cost thin film solar cells are an exciting photovoltaic technology option for generating cost-effective electricity in 1995 and beyond. This paper reviews the substantial advances made by several thin film solar cell technologies, namely, amorphous silicon, copper indium diselenide, cadmium telluride, and polycrystalline silicon. Recent examples of utility demonstration projects of these emerging materials are also discussed. 8 refs., 4 figs.

  12. Progress to Develop an Advanced Solar-Selective Coating

    SciTech Connect

    Kennedy, C. E.

    2008-03-01

    The progress to develop a durable advanced solar-selective coating will be described. Experimental work has focused on modeling high-temperature, solar-selective coatings; depositing the individual layers and modeled coatings; measuring the optical, thermal, morphology, and compositional properties and using the data to validate the modeled and deposited properties; re-optimizing the coating; and testing the coating performance and durability.

  13. Advances in passive imaging elements with micromirror array

    NASA Astrophysics Data System (ADS)

    Maekawa, Satoshi; Nitta, Kouichi; Matoba, Osamu

    2008-02-01

    We have proposed a new passive imaging optics which consists of a grid array of micro roof mirrors working as dihedral corner reflectors. Although this element forms mirror-like images at opposite side of objects, the images are real. Because the imaging principle of the proposed element is based on accumulation of rays, the design of each light path makes many kinds of devices possible. So, we propose two variations of such a device. One device consists of an array of micro retroreflectors and a half mirror, and it can also form real mirror-like images. The advantage of this device is wide range of view, because the displacement of each retororeflector is not limited on a plane unlike the roof mirror grid array. The other consists of an array of long dihedral corner reflectors. Although this structure has been already known as a roof mirror array, it can be used for imaging. This device forms two heterogeneous images. One is real at the same side of an object, and the other is virtual at the opposite side. This is a conjugate imaging optics of a slit mirror array whose mirror surface is perpendicular to the device surface. The advantage of a roor mirror array is that the real image has horizontal parallax and can be seen in air naturally.

  14. Recent Advances on Solar Global Magnetism and Variability

    NASA Astrophysics Data System (ADS)

    Brun, A. S.; Browning, M. K.; Dikpati, M.; Hotta, H.; Strugarek, A.

    2015-12-01

    We discuss recent observational, theoretical and numerical progress made in understanding the solar global magnetism and its short and long term variability. We discuss the physical process thought to be at the origin of the solar magnetic field and its 22-yr cycle, namely dynamo action, and the nonlinear interplay between convection, rotation, radiation and magnetic field, yielding modulations of the solar constant or of the large scale flows such as the torsional oscillations. We also discuss the role of the field parity and dynamo families in explaining the complex multipolar structure of the solar global magnetic field. We then present some key MHD processes acting in the deep radiative interior and discuss the probable topology of a primordial field there. Finally we summarize how helioseismology has contributed to these recent advances and how it could contribute to resolving current unsolved problems in solar global dynamics and magnetism.

  15. Large Absorption Enhancement in Ultrathin Solar Cells Patterned by Metallic Nanocavity Arrays

    NASA Astrophysics Data System (ADS)

    Wang, Wei; Zhang, Jiasen; Che, Xiaozhou; Qin, Guogang

    2016-10-01

    A new type of light trapping structure utilizing ring-shaped metallic nanocavity arrays is proposed for the absorption enhancement in ultrathin solar cells with few photonic waveguide modes. Dozens of times of broadband absorption enhancement in the spectral range of 700 to 1100 nm is demonstrated in an ultrathin Si3N4/c-Si/Ag prototype solar cell by means of finite-difference time-domain (FDTD) simulation, and this dramatic absorption enhancement can be attributed to the excitation of plasmonic cavity modes in these nanocavity arrays. The cavity modes optimally compensate for the lack of resonances in the longer wavelength range for ultrathin solar cells, and eventually a maximum Jsc enhancement factor of 2.15 is achieved under AM 1.5G solar illumination. This study opens a new perspective for light management in thin film solar cells and other optoelectronic devices.

  16. Large Absorption Enhancement in Ultrathin Solar Cells Patterned by Metallic Nanocavity Arrays

    PubMed Central

    Wang, Wei; Zhang, Jiasen; Che, Xiaozhou; Qin, Guogang

    2016-01-01

    A new type of light trapping structure utilizing ring-shaped metallic nanocavity arrays is proposed for the absorption enhancement in ultrathin solar cells with few photonic waveguide modes. Dozens of times of broadband absorption enhancement in the spectral range of 700 to 1100 nm is demonstrated in an ultrathin Si3N4/c-Si/Ag prototype solar cell by means of finite-difference time-domain (FDTD) simulation, and this dramatic absorption enhancement can be attributed to the excitation of plasmonic cavity modes in these nanocavity arrays. The cavity modes optimally compensate for the lack of resonances in the longer wavelength range for ultrathin solar cells, and eventually a maximum Jsc enhancement factor of 2.15 is achieved under AM 1.5G solar illumination. This study opens a new perspective for light management in thin film solar cells and other optoelectronic devices. PMID:27703176

  17. Recent advances in sensitized mesoscopic solar cells.

    PubMed

    Grätzel, Michael

    2009-11-17

    Perhaps the largest challenge for our global society is to find ways to replace the slowly but inevitably vanishing fossil fuel supplies by renewable resources and, at the same time, avoid negative effects from the current energy system on climate, environment, and health. The quality of human life to a large degree depends upon the availability of clean energy sources. The worldwide power consumption is expected to double in the next 3 decades because of the increase in world population and the rising demand of energy in the developing countries. This implies enhanced depletion of fossil fuel reserves, leading to further aggravation of the environmental pollution. As a consequence of dwindling resources, a huge power supply gap of 14 terawatts is expected to open up by year 2050 equaling today's entire consumption, thus threatening to create a planetary emergency of gigantic dimensions. Solar energy is expected to play a crucial role as a future energy source. The sun provides about 120,000 terawatts to the earth's surface, which amounts to 6000 times the present rate of the world's energy consumption. However, capturing solar energy and converting it to electricity or chemical fuels, such as hydrogen, at low cost and using abundantly available raw materials remains a huge challenge. Chemistry is expected to make pivotal contributions to identify environmentally friendly solutions to this energy problem. One area of great promise is that of solar converters generally referred to as "organic photovoltaic cells" (OPV) that employ organic constituents for light harvesting or charge carrier transport. While this field is still in its infancy, it is receiving enormous research attention, with the number of publications growing exponentially over the past decade. The advantage of this new generation of solar cells is that they can be produced at low cost, i.e., potentially less than 1 U.S. $/peak watt. Some but not all OPV embodiments can avoid the expensive and energy

  18. Analysis of costs of gallium arsenide and silicon solar arrays for space power applications

    NASA Technical Reports Server (NTRS)

    Jefferies, K. S.

    1981-01-01

    A parametric analysis was performed to compare the costs of silicon and gallium arsenide arrays for Earth orbital missions. The missions included electric power in low Earth orbit (LEO), electric power in geosynchronous Earth orbit (GEO), and power for electric propulsion of a LEO to GEO orbit transfer mission. Inputs to the analysis for all missions included launch and purchase costs of the array. For the orbit transfer mission, the launch and purchase costs of the electric propulsion system were added. Radiation flux as a function of altitude and rediation tolerance as a function of cell type were used to determine power degradation for each mission. Curves were generated that show the sensitivity of launch-array cost and total mission cost to a variety of input parameters for each mission. These parameters included mission duration, cover glass thickness, array specific cost, array specific mass, and solar cell efficiency. Solar concentration was considered and the sensitivities of cost to concentration ratio, concentrator costs, and concentrator mass were also evaluated. Results indicate that solar cell development should give a high priority to reducing array costs and that the development of low cost, lightweight, solar concentrators should be pursued.

  19. Electrostatic Discharge Test of Multi-Junction Solar Array Coupons After Combined Space Environmental Exposures

    NASA Technical Reports Server (NTRS)

    Wright, Kenneth H.; Schneider, Todd; Vaughn, Jason; Hoang, Bao; Funderburk, Victor V.; Wong, Frankie; Gardiner, George

    2010-01-01

    A set of multi-junction GaAs/Ge solar array test coupons were subjected to a sequence of 5-year increments of combined environmental exposure tests. The test coupons capture an integrated design intended for use in a geosynchronous (GEO) space environment. A key component of this test campaign is conducting electrostatic discharge (ESD) tests in the inverted gradient mode. The protocol of the ESD tests is based on the ISO/CD 11221, the ISO standard for ESD testing on solar array panels. This standard is currently in its final review with expected approval in 2010. The test schematic in the ISO reference has been modified with Space System/Loral designed circuitry to better simulate the on-orbit operational conditions of its solar array design. Part of the modified circuitry is to simulate a solar array panel coverglass flashover discharge. All solar array coupons used in the test campaign consist of 4 cells. The ESD tests are performed at the beginning of life (BOL) and at each 5-year environment exposure point. The environmental exposure sequence consists of UV radiation, electron/proton particle radiation, thermal cycling, and ion thruster plume. This paper discusses the coverglass flashover simulation, ESD test setup, and the importance of the electrical test design in simulating the on-orbit operational conditions. Results from 5th-year testing are compared to the baseline ESD characteristics determined at the BOL condition.

  20. Observations of Transient ISS Floating Potential Variations During High Voltage Solar Array Operations

    NASA Technical Reports Server (NTRS)

    Willis, Emily M.; Minow, Joseph I.; Parker, Linda N.; Pour, Maria Z. A.; Swenson, Charles; Nishikawa, Ken-ichi; Krause, Linda Habash

    2016-01-01

    The International Space Station (ISS) continues to be a world-class space research laboratory after over 15 years of operations, and it has proven to be a fantastic resource for observing spacecraft floating potential variations related to high voltage solar array operations in Low Earth Orbit (LEO). Measurements of the ionospheric electron density and temperature along the ISS orbit and variations in the ISS floating potential are obtained from the Floating Potential Measurement Unit (FPMU). In particular, rapid variations in ISS floating potential during solar array operations on time scales of tens of milliseconds can be recorded due to the 128 Hz sample rate of the Floating Potential Probe (FPP) pro- viding interesting insight into high voltage solar array interaction with the space plasma environment. Comparing the FPMU data with the ISS operations timeline and solar array data provides a means for correlating some of the more complex and interesting transient floating potential variations with mission operations. These complex variations are not reproduced by current models and require further study to understand the underlying physical processes. In this paper we present some of the floating potential transients observed over the past few years along with the relevant space environment parameters and solar array operations data.

  1. Dust Accumulation and Solar Panel Array Performance on the Mars Exploration Rover (MER) Project

    NASA Technical Reports Server (NTRS)

    Turgay, Eren H.

    2004-01-01

    One of the most fundamental design considerations for any space vehicle is its power supply system. Many options exist, including batteries, fuel cells, nuclear reactors, radioisotopic thermal generators (RTGs), and solar panel arrays. Solar arrays have many advantages over other types of power generation. They are lightweight and relatively inexpensive, allowing more mass and funding to be allocated for other important devices, such as scientific instruments. For Mars applications, solar power is an excellent option, especially for long missions. One might think that dust storms would be a problem; however, while dust blocks some solar energy, it also scatters it, making it diffuse rather than beamed. Solar cells are still able to capture this diffuse energy and convert it into substantial electrical power. For these reasons, solar power was chosen to be used on the 1997 Mars Pathfinder mission. The success of this mission set a precedent, as NASA engineers have selected solar power as the energy system of choice for all future Mars missions, including the Mars Exploration Rover (MER) Project. Solar sells have their drawbacks, however. They are difficult to manufacture and are relatively fragile. In addition, solar cells are highly sensitive to different parts of the solar spectrum, and finding the correct balance is crucial to the success of space missions. Another drawback is that the power generated is not a constant with respect to time, but rather changes with the relative angle to the sun. On Mars, dust accumulation also becomes a factor. Over time, dust settles out of the atmosphere and onto solar panels. This dust blocks and shifts the frequency of the incoming light, degrading solar cell performance. My goal is to analyze solar panel telemetry data from the two MERs (Spirit and Opportunity) in an effort to accurately model the effect of dust accumulation on solar panels. This is no easy process due to the large number of factors involved. Changing solar

  2. Absorption efficiency enhancement in inorganic and organic thin film solar cells via plasmonic honeycomb nanoantenna arrays.

    PubMed

    Tok, Rüştü Umut; Sendur, Kürşat

    2013-08-15

    We demonstrate theoretically that by embedding plasmonic honeycomb nanoantenna arrays into the active layers of inorganic (c-Si) and organic (P3HT:PCBM/PEDOT:PSS) thin film solar cells, absorption efficiency can be improved. To obtain the solar cell absorption spectrum that conforms to the solar radiation, spectral broadening is achieved by breaking the symmetry within the Wigner-Seitz unit cell on a uniform hexagonal grid. For optimized honeycomb designs, absorption efficiency enhancements of 106.2% and 20.8% are achieved for c-Si and P3HT:PCBM/PEDOT:PSS thin film solar cells, respectively. We have demonstrated that the transverse modes are responsible for the enhancement in c-Si solar cells, whereas both the longitudinal and transverse modes, albeit weaker, are the main enhancement mechanisms for P3HT:PCBM/PEDOT:PSS solar cells. For both inorganic and organic solar cells, the absorption enhancement is independent of polarization.

  3. Hubble Space telescope thermal cycle test report for large solar array samples with BSFR cells (Sample numbers 703 and 704)

    NASA Technical Reports Server (NTRS)

    Alexander, D. W.

    1992-01-01

    The Hubble space telescope (HST) solar array was designed to meet specific output power requirements after 2 years in low-Earth orbit, and to remain operational for 5 years. The array, therefore, had to withstand 30,000 thermal cycles between approximately +100 and -100 C. The ability of the array to meet this requirement was evaluated by thermal cycle testing, in vacuum, two 128-cell solar cell modules that exactly duplicated the flight HST solar array design. Also, the ability of the flight array to survive an emergency deployment during the dark (cold) portion of an orbit was evaluated by performing a cold-roll test using one module.

  4. Solar Array Reliability at GSFC and Possibilities for Improvement

    NASA Technical Reports Server (NTRS)

    Gaddy, Edward

    2005-01-01

    Contents include the following: GSFC recent missions. GSFC array failure rate. Industry concern.s. GSFC on orbit problems. GSFC test problems. Repeaters. A thought or two. Some improvements. A real challenge. Peace at last.

  5. Performance of High-Efficiency Advanced Triple-Junction Solar Panels for the LILT Mission Dawn

    NASA Technical Reports Server (NTRS)

    Fatemi, Navid S.; Sharma, Surya; Buitrago, Oscar; Sharps, Paul R.; Blok, Ron; Kroon, Martin; Jalink, Cees; Harris, Robin; Stella, Paul; Distefano, Sal

    2005-01-01

    NASA's Discovery Mission Dawn is designed to (LILT) conditions. operate within the solar system's Asteroid belt, where the large distance from the sun creates a low-intensity, low-temperature (LILT) condition. To meet the mission power requirements under LlLT conditions, very high-efficiency multi-junction solar cells were selected to power the spacecraft to be built by Orbital Sciences Corporation (OSC) under contract with JPL. Emcore's InGaP/InGaAs/Ge advanced triple-junction (ATJ) solar cells, exhibiting an average air mass zero (AMO) efficiency of greater than 27.6% (one-sun, 28 C), were used to populate the solar panels [1]. The two solar array wings, to be built by Dutch Space, with 5 large- area panels each (total area of 36.4 sq. meters) are projected to produce between 10.3 kWe and 1.3 kWe of end-of life (EOL) power in the 1.0 to 3.0 AU range, respectively. The details of the solar panel design, testing and power analysis are presented.

  6. Size Distribution of Genesis Solar Wind Array Collector Fragments Recovered

    NASA Technical Reports Server (NTRS)

    Allton, J. H.; Stansbery, E. K.; McNamara, K. M.

    2005-01-01

    Genesis launched in 2001 with 271 whole and 30 half hexagonally-shaped collectors mounted on 5 arrays, comprised of 9 materials described in [1]. The array collectors were damaged during re-entry impact in Utah in 2004 [2], breaking into many smaller pieces and dust. A compilation of the number and approximate size of the fragments recovered was compiled from notes made during the field packaging performed in the Class 10,000 cleanroom at Utah Test and Training Range [3].

  7. Non-linear phenomena in films of solar arrays

    NASA Technical Reports Server (NTRS)

    Zak, M.

    1979-01-01

    The paper assesses nonlinear effects in films which are associated with the instability of their shape as a result of contractions during longitudinal and transverse in-plane oscillations. The following problems are solved analytically: transverse in-plane oscillations, longitudinal oscillations in films of rotating solar sail, transverse in-plane oscillations in films of a rotating solar sail, and effect of damping in films of a rotating solar sail. The reason for damping lies in the loss of kinetic energy during absorption of the film particles by root wrinkles without reflection (absolutely inelastic shock).

  8. Solar array design based on shadow analysis for increasing net energy collection in a competition vehicle

    NASA Astrophysics Data System (ADS)

    Osorio-Gómez, Gilberto; Mejía-Gutiérrez, Ricardo; Suárez-Castañeda, Nicolás; Gil-Herrera, Ana; Barrera-Velásquez, Jorge

    2015-01-01

    Photovoltaic (PV) applications such as in the architectural, automotive, and aerospace industries face design contradictions because they are expected to produce a lot of energy but are constrained by available area, surface shape, incident irradiance, shadows, and other aspects that have a negative influence on the energy produced by the solar panel. Solar competition vehicles are some of these challenging PV applications. The design of such solar arrays needs to consider efficiency evaluation in order to optimize space; it is difficult not to install solar modules in areas impacted by shadows. A design procedure for a solar array configuration based on shadow analysis for competition vehicles is presented. The principle is that shadows in moving objects can be simulated, since the vehicle, the earth and the sun are are moving in semipredictable patterns, thus net energy collection can be forecast. The case study presented is the solar array design of a vehicle that participated in the World Solar Challenge 2013. The obtained results illustrate how the employment of the procedure gives insights on important aspects to consider and also delivers qualitative and quantitative information for decision making. In addition, the experience in competition highlights some issues to be considered, modified, or improved in further vehicle designs.

  9. Molecular Substrate Alteration by Solar Wind Radiation Documented on Flown Genesis Mission Array Materials

    NASA Technical Reports Server (NTRS)

    Calaway, Michael J.; Stansbery, Eileen K.

    2006-01-01

    The Genesis spacecraft sampling arrays were exposed to various regimes of solar wind during flight that included: 313.01 days of high-speed wind from coronal holes, 335.19 days of low-speed inter-stream wind, 191.79 days of coronal mass ejections, and 852.83 days of bulk solar wind at Lagrange 1 orbit. Ellipsometry measurements taken at NASA s Johnson Space Center show that all nine flown array materials from the four Genesis regimes have been altered by solar wind exposure during flight. These measurements show significant changes in the optical constant for all nine ultra-pure materials that flew on Genesis when compared with their non-flight material standard. This change in the optical constant (n and k) of the material suggests that the molecular structure of the all nine ultra-pure materials have been altered by solar radiation. In addition, 50 samples of float-zone and czochralski silicon bulk array ellipsometry results were modeled with an effective medium approximation layer (EMA substrate layer) revealing a solar radiation molecular damage zone depth below the SiO2 native oxide layer ranging from 392 to 613 . This bulk solar wind radiation penetration depth is comparable to the depth of solar wind implantation depth of Mg measured by SIMS and SARISA.

  10. Application of a silicon photodiode array for solar edge tracking in the Halogen Occultation Experiment

    NASA Technical Reports Server (NTRS)

    Mauldin, L. E., III; Moore, A. S.; Stump, C. S.; Mayo, L. S.

    1985-01-01

    The optical and electronic design of the Halogen Occultation Experiment (HALOE) elevation sunsensor is described. This system uses a Galilean telescope to form a solar image on a linear silicon photodiode array. The array is a self-scanned, monolithic charge coupled device. The addresses of both solar edges imaged on the array are used by the control/pointing system to scan the HALOE science instantaneous-field-of-view (IFOV) across the vertical solar diameter during instrument calibration, and then maintain the science IFOV four arcmin below the top edge during the science data occultation event. Vertical resolution of 16 arcsec and a radiometric dynamic range of 100 are achieved at the 0.7 micrometer operating wavelength. The design provides for loss of individual photodiode elements without loss of angular tracking capability. The HALOE instrument is a gas correlation radiometer that is now being developed by NASA Langley Research Center for the Upper Atmospheric Research Satellite.

  11. Design and development of a brushless, direct drive solar array reorientation system

    NASA Technical Reports Server (NTRS)

    Jessee, R. D.

    1972-01-01

    This report covers the design and development of the laboratory model, and is essentially a compilation of reports covering the system and its various parts. To enhance completeness, the final report of Phase 1 covering circuit development of the controller is also included. A controller was developed for a brushless, direct-drive, single axis solar array reorientation system for earth-pointed, passively-stabilized spacecraft. A control systems was designed and breadboard circuits were built and tested for performance. The controller is designed to take over automatic control of the array on command after the spacecraft is stabilized in orbit. The controller will orient the solar array to the sun vector and automatically track to maintain proper orientation. So long as the orbit is circular, orientation toward the sun is maintained even though the spacecraft goes into the shadow of the earth. Particular attention was given in the design to limit reaction between the array and the spacecraft.

  12. The solar array-induced disturbance of the Hubble Space Telescope pointing system

    NASA Technical Reports Server (NTRS)

    Foster, C. L.; Tinker, M. L.; Nurre, G. S.; Till, W. A.

    1995-01-01

    The investigation of the vibrational disturbances of the Hubble Space Telescope that were discovered soon after deployment in orbit is described in detail. It was found that the disturbances were particularly evident during orbital day-night crossings, and that the magnitudes of the disturbances were considerably larger than the design jitter requirements. This paper describes the process by which the vibrations were characterized and isolated to a particular mechanism. The analysis of the flight data and comparisons with computer simulation results showed that the source of the disturbances was the thermally driven deformation of the solar arrays in conjunction with frictional effects in the array mechanisms. The control system was successfully modified to attenuate the disturbances to tolerable levels pending mechanical and thermal redesign of the solar arrays. The new arrays were installed during the first space telescope servicing mission and, in combination with the enhanced control system algorithm, reduced the disturbances to satisfactory levels.

  13. Solar-Array-Induced Disturbance of the Hubble Space Telescope Pointing System

    NASA Technical Reports Server (NTRS)

    Foster, Carlton L.; Tinker, Michael L.; Nurre, Gerald S.; Till, William A.

    1995-01-01

    The investigation of the vibrational disturbances of the Hubble Space Telescope that were discovered soon after deployment in orbit is described in detail. It was found that the disturbances were particularly evident during orbital day-night crossings, and that the magnitude of the disturbances was considerably larger than the design jitter requirement. This paper describes the process by which the vibrations were characterized and isolated to a particular mechanism. The analysis of the flight data and comparisons with computer simulation results showed that the source of the disturbances was the thermally driven deformation of the solar arrays in conjunction with frictional effects in the array mechanisms. The control system was successfully modified to attenuate the disturbances to tolerable levels pending mechanical and thermal redesign of the solar arrays. The new arrays were installed during the first Space Telescope servicing mission, and in combination with the enhanced control system algorithm reduced the disturbances to satisfactory levels.

  14. Highly efficient ultrathin-film amorphous silicon solar cells on top of imprinted periodic nanodot arrays

    SciTech Connect

    Yan, Wensheng Gu, Min; Tao, Zhikuo; Ong, Thiam Min Brian

    2015-03-02

    The addressing of the light absorption and conversion efficiency is critical to the ultrathin-film hydrogenated amorphous silicon (a-Si:H) solar cells. We systematically investigate ultrathin a-Si:H solar cells with a 100 nm absorber on top of imprinted hexagonal nanodot arrays. Experimental evidences are demonstrated for not only notable silver nanodot arrays but also lower-cost ITO and Al:ZnO nanodot arrays. The measured external quantum efficiency is explained by the simulation results. The J{sub sc} values are 12.1, 13.0, and 14.3 mA/cm{sup 2} and efficiencies are 6.6%, 7.5%, and 8.3% for ITO, Al:ZnO, and silver nanodot arrays, respectively. Simulated optical absorption distribution shows high light trapping within amorphous silicon layer.

  15. Periodically Aligned Si Nanopillar Arrays as Efficient Antireflection Layers for Solar Cell Applications

    PubMed Central

    2010-01-01

    Periodically aligned Si nanopillar (PASiNP) arrays were fabricated on Si substrate via a silver-catalyzed chemical etching process using the diameter-reduced polystyrene spheres as mask. The typical sub-wavelength structure of PASiNP arrays had excellent antireflection property with a low reflection loss of 2.84% for incident light within the wavelength range of 200–1,000 nm. The solar cell incorporated with the PASiNP arrays exhibited a power conversion efficiency (PCE) of ~9.24% with a short circuit current density (JSC) of ~29.5 mA/cm2 without using any extra surface passivation technique. The high PCE of PASiNP array-based solar cell was attributed to the excellent antireflection property of the special periodical Si nanostructure. PMID:21124636

  16. Terrestrial solar cell module automated array assembly, task 4

    NASA Technical Reports Server (NTRS)

    1978-01-01

    A cost effective design and manufacturing process which would produce solar cell modules capable of meeting qualification test criteria was developed. Emphasis was placed on the development of an aluminum paste back contact process.

  17. Modeling, Simulation, and Control of a Solar Electric Propulsion Vehicle in Near-Earth Vicinity Including Solar Array Degradation

    NASA Technical Reports Server (NTRS)

    Witzberger, Kevin (Inventor); Hojnicki, Jeffery (Inventor); Manzella, David (Inventor)

    2016-01-01

    Modeling and control software that integrates the complexities of solar array models, a space environment, and an electric propulsion system into a rigid body vehicle simulation and control model is provided. A rigid body vehicle simulation of a solar electric propulsion (SEP) vehicle may be created using at least one solar array model, at least one model of a space environment, and at least one model of a SEP propulsion system. Power availability and thrust profiles may be determined based on the rigid body vehicle simulation as the SEP vehicle transitions from a low Earth orbit (LEO) to a higher orbit or trajectory. The power availability and thrust profiles may be displayed such that a user can use the displayed power availability and thrust profiles to determine design parameters for an SEP vehicle mission.

  18. High Voltage Solar Array Arc Testing for a Direct Drive Hall Effect Thruster System

    NASA Technical Reports Server (NTRS)

    Schneider, Todd; Carruth, M. R., Jr.; Vaughn, J. A.; Jongeward, G. A.; Mikellides, I. G.; Ferguson, D.; Kerslake, T. W.; Peterson, T.; Snyder, D.; Hoskins, A.

    2004-01-01

    The deleterious effects of spacecraft charging are well known, particularly when the charging leads to arc events. The damage that results from arcing can severely reduce system lifetime and even cause critical system failures. On a primary spacecraft system such as a solar array, there is very little tolerance for arcing. Motivated by these concerns, an experimental investigation was undertaken to determine arc thresholds for a high voltage (200-500 V) solar array in a plasma environment. The investigation was in support of a NASA program to develop a Direct Drive Hall-Effect Thruster (D2HET) system. By directly coupling the solar array to a Hall-effect thruster, the D2HET program seeks to reduce mass, cost and complexity commonly associated with the power processing in conventional power systems. In the investigation, multiple solar array technologies and configurations were tested. The cell samples were biased to a negative voltage, with an applied potential difference between them, to imitate possible scenarios in solar array strings that could lead to damaging arcs. The samples were tested in an environment that emulated a low-energy, HET-induced plasma. Short duration trigger arcs as well as long duration sustained arcs were generated. Typical current and voltage waveforms associated with the arc events are presented. Arc thresholds are also defined in terms of voltage, current and power. The data will be used to propose a new, high-voltage (greater than 300 V) solar array design for which the likelihood of damage from arcing is minimal.

  19. High Voltage Solar Array ARC Testing for a Direct Drive Hall Effect Thruster System

    NASA Technical Reports Server (NTRS)

    Schneider, T.; Vaughn, J.; Carruth, M. R.; Mikellides, I. G.; Jongeward, G. A.; Peterson, T.; Kerslake, T. W.; Snyder, D.; Ferguson, D.; Hoskins, A.

    2003-01-01

    The deleterious effects of spacecraft charging are well known, particularly when the charging leads to arc events. The damage that results from arcing can severely reduce system lifetime and even cause critical system failures. On a primary spacecraft system such as a solar array, there is very little tolerance for arcing. Motivated by these concerns, an experimental investigation was undertaken to determine arc thresholds for a high voltage (200-500 V) solar array in a plasma environment. The investigation was in support of a NASA program to develop a Direct Drive Hall-Effect Thruster (112HET) system. By directly coupling the solar array to a Hall-effect thruster, the D2HET program seeks to reduce mass, cost and complexity commonly associated with the power processing in conventional power systems. In the investigation, multiple solar array technologies and configurations were tested. The cell samples were biased to a negative voltage, with an applied potential difference between them, to imitate possible scenarios in solar array strings that could lead to damaging arcs. The samples were tested in an environment that emulated a low-energy, HET-induced plasma. Short duration "trigger" arcs as well as long duration "sustained" arcs were generated. Typical current and voltage waveforms associated with the arc events are presented. Arc thresholds are also defined in terms of vo!tage, (current and power. The data will be used to propose a new, high-voltage (>300 V) solar array design for which the likelihood of damage from arcing is minimal.

  20. Phase 1 of the automated array assembly task of the low cost silicon solar array project

    NASA Technical Reports Server (NTRS)

    Pryor, R. A.; Grenon, L. A.; Coleman, M. G.

    1978-01-01

    The results of a study of process variables and solar cell variables are presented. Interactions between variables and their effects upon control ranges of the variables are identified. The results of a cost analysis for manufacturing solar cells are discussed. The cost analysis includes a sensitivity analysis of a number of cost factors.

  1. An evaluation of spectrally selective reflectors (cold mirror membranes) for use with concentrator solar arrays

    NASA Astrophysics Data System (ADS)

    Beauchamp, W. T.; Rancourt, J. D.; Lott, D. R.

    1980-06-01

    Spectrally selective reflector (SSR) coatings on lightweight transparent membranes were evaluated as a method of concentrating light for achieving increased power without suffering severe temperature losses on solar arrays. Analysis and laboratory tests indicate that SSR concentrators are more effective than opaque reflectors with both silicon and GaAs cells for increasing array output. Large area SSR membranes can be produced in roll to roll coaters at cost that will be competitive with other reflecting membranes.

  2. Solar Arrays for Direct-Drive Electric Propulsion: Arcing at High Voltages

    NASA Technical Reports Server (NTRS)

    Schneider, Todd A.; Mikellides, I. G.; Jongeward, G. A.; Peterson, T.; Kerslake, T. W.; Snyder, D.; Ferguson, D.

    2004-01-01

    The results from an experimental investigation to assess arcing during operation of high voltage solar arrays in a plasma environment are presented. The experiments were part of an effort to develop systems that would allow safe operation of Hall-Effect Thrustefls) in direct-drive mode. Arc discharges are generated when the array is biased negative with respect to the plasma. If sustained for long periods of time between adjacent solar cells, arcs may severely damage a solar array, thus significantly shortening its lifetime. Most often sustained arcs are triggered by plasma produced during short-duration discharge arcs (approximately 20 microseconds). These trigger arcs are sparked between the semiconducting cell and the covering dielectric. Both trigger and sustained (greater than 1 millisecond) arcs have been captured during the tests. Current and voltage waveforms associated with the different arc events are presented. The test results have defined operational limits (thresholds) for the various array concepts studied that minimize the likelihood of damage from sustained arcs. Experimental trends regarding the effect of the solar array substrate on arc duration are also presented.

  3. Solar array experiments on the SPHINX satellite. [Space Plasma High voltage INteraction eXperiment satellite

    NASA Technical Reports Server (NTRS)

    Stevens, N. J.

    1974-01-01

    The Space Plasma, High Voltage Interaction Experiment (SPHINX) is the name given to an auxiliary payload satellite scheduled to be launched in January 1974. The principal experiments carried on this satellite are specifically designed to obtain the engineering data on the interaction of high voltage systems with the space plasma. The classes of experiments are solar array segments, insulators, insulators with pin holes and conductors. The satellite is also carrying experiments to obtain flight data on three new solar array configurations: the edge illuminated-multijunction cells, the teflon encased cells, and the violet cells.

  4. Zarya Energy Balance Analysis: The Effect of Spacecraft Shadowing on Solar Array Performance

    NASA Technical Reports Server (NTRS)

    Hoffman, David J.; Kolosov, Vladimir

    1999-01-01

    The first element of the International Space Station (ISS). Zarya, was funded by NASA and built by the Russian aerospace company Khrunichev State Research and Production Space Center (KhSC). NASA Glenn Research Center (GRC) and KhSC collaborated in performing analytical predictions of the on-orbit electrical performance of Zarya's solar arrays. GRC assessed the pointing characteristics of and shadow patterns on Zarya's solar arrays to determine the average solar energy incident on the arrays. KHSC used the incident energy results to determine Zarya's electrical power generation capability and orbit-average power balance. The power balance analysis was performed over a range of solar beta angles and vehicle operational conditions. This analysis enabled identification of problems that could impact the power balance for specific flights during ISS assembly and was also used as the primary means of verifying that Zarya complied with electrical power requirements. Analytical results are presented for select stages in the ISS assembly sequence along with a discussion of the impact of shadowing on the electrical performance of Zarya's solar arrays.

  5. Low cost, high concentration ratio solar cell array for space applications

    NASA Technical Reports Server (NTRS)

    Patterson, R. E.; Rauschenbach, H. S.; Cannady, M. D.; Whang, U. S.; Crabtree, W. L.

    1981-01-01

    A miniaturized Cassegrainian-type concentrator solar array concept for space applications is described. In-orbit cell operating temperatures near 80 C are achieved with purely passive cell cooling and a net concentration ratio of 100. A multiplicity of miniaturized, rigid solar cell concentrator subassemblies are electrically interconnected in conventional fashion and mounted into rigid frames to form concentrator solar panel assemblies approximately 14-mm thick. A plurality of such interconnected panels forms a stowable and deployable solar cell blanket. It is projected that for 20% efficient silicon cells an array of 500 kW beginning-of-life output capability, including orbiter cradle structures, can be transported by a single shuttle orbiter flight into low earth orbit. In-orbit array specific performance is calculated to be approximately 100 W/sq m and 20 W/kg, including all stowage, deployment and array figure control equipment designed for a 30-year orbital life. Higher efficiency gallium arsenide and multiple band gap solar cells will improve these performance factors correspondingly.

  6. Recent Advances in Solar Sail Propulsion at NASA

    NASA Technical Reports Server (NTRS)

    Johnson, Les; Young, Roy M.; Montgomery, Edward E., IV

    2006-01-01

    Supporting NASA's Science Mission Directorate, the In-Space Propulsion Technology Program is developing solar sail propulsion for use in robotic science and exploration of the solar system. Solar sail propulsion will provide longer on-station operation, increased scientific payload mass fraction, and access to previously inaccessible orbits for multiple potential science missions. Two different 20-meter solar sail systems were produced and successfully completed functional vacuum testing last year in NASA Glenn's Space Power Facility at Plum Brook Station, Ohio. The sails were designed and developed by ATK Space Systems and L'Garde, respectively. These sail systems consist of a central structure with four deployable booms that support the sails. This sail designs are robust enough for deployments in a one atmosphere, one gravity environment, and are scalable to much larger solar sails-perhaps as much as 150 meters on a side. In addition, computation modeling and analytical simulations have been performed to assess the scalability of the technology to the large sizes (>150 meters) required for first generation solar sails missions. Life and space environmental effects testing of sail and component materials are also nearly complete. This paper will summarize recent technology advancements in solar sails and their successful ambient and vacuum testing.

  7. Recent Advances in Solar Sail Propulsion Systems at NASA

    NASA Technical Reports Server (NTRS)

    Johnson, Les

    2006-01-01

    Supporting NASA's Science Mission Directorate, the In-Space Propulsion Technology Program is developing solar sail propulsion for use in robotic science and exploration of the solar system. Solar sail propulsion has the potential to provide longer on-station operation, increased scientific payload mass fraction, and access to previously inaccessible orbits for multiple potential science missions. Two different 20-meter solar sail systems were produced and successfully completed functional vacuum testing last year in NASA Glenn s Space Power Facility at Plum Brook Station Ohio. The sails were designed and developed by ATK Space Systems and L'Garde, respectively. The sail systems consist of a central structure with four deployable booms that support the sails. The sail designs are robust enough for deployments in a one atmosphere, one gravity environment and are scalable to much larger solar sails - perhaps as large as 150 meters on a side. In addition, computational modeling and analytical simulations have been performed to assess the scalability of the technology to the large sizes (150 meters) required to implement the first generation of missions using solar sails. Life and space environmental effects testing of sail and component materials are also nearly complete. This paper will summarize recent technology advancements in solar sails and their successful ambient and vacuum environment testing.

  8. Artist concept of astronaut attempting to free solar array on Skylab

    NASA Technical Reports Server (NTRS)

    1973-01-01

    An artist's concept showing astronaut Charles Conrad Jr., Skylab 2 commander, attempting to free the solar array system wing on the Orbital Workshop during extravehicular activity at the Skylab 1 and 2 space station cluster in earth orbit. The astronaut in the background is Joseph P. Kerwin, Skylab 2 science pilot. Here, Conrad is pushing up on the Beam Erection Tether (BET) to raise the stuck solar panel.

  9. Flexible Dye-Sensitized Solar Cell Based on Vertical ZnO Nanowire Arrays

    PubMed Central

    2011-01-01

    Flexible dye-sensitized solar cells are fabricated using vertically aligned ZnO nanowire arrays that are transferred onto ITO-coated poly(ethylene terephthalate) substrates using a simple peel-off process. The solar cells demonstrate an energy conversion efficiency of 0.44% with good bending tolerance. This technique paves a new route for building large-scale cost-effective flexible photovoltaic and optoelectronic devices. PMID:27502660

  10. Solar Powered Aircraft, Photovoltaic Array/Battery System Tabletop Demonstration: Design and Operation Manual

    NASA Technical Reports Server (NTRS)

    Colozza, Anthony J.; Scheiman, David A.; Bailey, Sheila (Technical Monitor)

    2000-01-01

    A system was constructed to demonstrate the power system operation of a solar powered aircraft. The system consists of a photovoltaic (PV) array, a charge controller, a battery, an electric motor and propeller. The system collects energy from the PV array and either utilizes this energy to operate an electric motor or stores it in a rechargeable battery for future use. The system has a control panel which displays the output of the array and battery as well as the total current going to the electric motor. The control panel also has a means for adjusting the output to the motor to control its speed. The entire system is regulated around 12 VDC.

  11. Chapter 1: Recent Advances in Solar Physics

    NASA Astrophysics Data System (ADS)

    Dwivedi, B. N.

    2008-10-01

    For millennia, the Sun (and the universe) has been viewed in the visual light. As the bestower of light and life, the ancients made God out of the Sun. With the Babylonians, or with the multiple origins with the Chinese, Egyptians and Indians, quoting the Rig Veda:"All that exists was born from Sūrya, the God of gods.", we have come a long way to understanding the Sun. In the early seventeenth century, however, Galileo showed that the Sun was not an immaculate object. Thus began our scientific interests in our nearest stellar neighbour, the Sun (cf., Figure 1.1.), with its sunspots and the related solar activity. The observations of the Sun and their interpretations are of universal importance for at least two reasons: First, the Sun is the source of energy for the entire planetary system and all aspects of our life have direct impact on what happens on the Sun; and second, the Sun's proximity makes it unique among the billions of stars in the sky of which we can resolve its surface features and study physical processes at work...

  12. Solar array conceptual design for the Halley's Comet ion drive mission, phase 2

    NASA Technical Reports Server (NTRS)

    Rayl, G. J.; Speight, K. M.; Stanhouse, R. W.

    1977-01-01

    Conceptual design studies were performed directed toward a high power, ultralightweight solar array, compatible with the requirements for the Halley's Comet Ion Drive Mission. A planar, rollup array design concept capable of producing 120 kW at 1 AU and 6 kW at 4.5 AU, and a concentrator, rollup array design concept capable of producing 60 kW at 1 AU and 15.5 kW at 4.5 AU evolved. Both arrays make maximum use of thin film, lightweight technology. The Halley's Comet spacecraft and mission requirements developed from preliminary definition to a more finalized and mature design. As solar array requirements were updated, conceptual design iterations were necessary to keep pace with the rapidly changing program objectives and goals. The Halley's Comet Mission program status and design approaches were reviewed and more realistic power requirements at 4.5 AU for the ion engines were established at the 12 to 16 kW range. This higher power necessitated a change from the planar array design to a concentrator array design in order to remain within suitable cost and weight objectives.

  13. Low Earth orbit durability evaluation of protected silicone for advanced refractive photovoltaic concentrator arrays

    NASA Technical Reports Server (NTRS)

    Degroh, Kim K.; Mccollum, Timothy A.

    1994-01-01

    The need for efficient, cost effective sources of electrical power in space has led to the development of photovoltaic power systems which make use of novel refractive solar concentrators. These concentrators have been conceived in both point-focus and linear-focus designs. Current concentrator lenses are fabricated from flexible silicones with Fresnel facets along their inside surface. To insure the efficient operation of these power systems, the concentrator lenses must be durable and the silicone material must remain specularly transmitting over a reasonable lifetime in low Earth orbit (LEO) and other space environments. Because of the vulnerability of silicones to atomic oxygen and ultraviolet radiation in LEO these lenses have been coated with a multi-layer metal oxide protective coating. The objective of this research was to evaluate the LEO durability of the multilayer coated silicone for advanced refractive photovoltaic concentrator arrays with respect to optical properties and microstructure. Flat metal oxide coated silicone samples were exposed to ground-laboratory and in-space atomic oxyqen for durability evaluation.

  14. Forest and grassland ecosystem studies using the advanced solid-state array spectroradiometer

    NASA Technical Reports Server (NTRS)

    Irons, James R.; Ranson, K. Jon; Williams, Darrel L.; Irish, Richard R.

    1989-01-01

    The advanced solid-state array spectroradiometer (ASAS) is an airborne, off-nadir pointing imaging spectroradiometer used to acquire bidirectional radiance data for terrestrial targets. As its platform aircraft flies over a target the sensor can image the target through a sequence of at least seven fore-to-aft view directions ranging up to 45 deg on either side of nadir. ASAS acquires data for 29 spectral bands in the visible and near-infrared portions of the spectrum with a resolution of 15 nm. ASAS data were recently acquired for a prairie ecosystem and a northern forest ecosystem. The data demonstrate the combined effects of reflectance anisotropy and increased atmospheric path length on off-nadir observations. One result of these effects is a variation in vegetation indices as a function of view direction. Normalized-difference-vegetation-indices for prairie grass, coniferous, and deciduous canopies varied up to 14 percent, 23 percent, and 6 percent, respectively, relative to nadir as a function of view zenith angle along the solar principal plane.

  15. Advancements in the micromirror array projector technology II

    NASA Astrophysics Data System (ADS)

    Beasley, D. B.; Bender, Matt; Crosby, Jay; McCall, Sean; Messer, Tim; Saylor, Daniel A.

    2005-05-01

    The Micromirror Array Projector System (MAPS) is a state-of-the-art dynamic scene projector developed by Optical Sciences Corporation (OSC) for Hardware-In-the-Loop (HWIL) simulation and sensor test applications. Since the introduction of the first MAPS in 2001, OSC has continued to improve the technology and develop systems for new projection and test applications. The MAPS is based upon the Texas Instruments Digital Micromirror Device (DMD) which has been modified to project high resolution, realistic imagery suitable for testing sensors and seekers operating in the UV, visible, NIR, and IR wavebands. This paper reviews the basic design and describes recent developments and new applications of the MAPS technology. Recent developments for the MAPS include increasing the format of the micromirror array to 1280x1024, increasing the video frame rate to >230 Hz, development of a DMD active cooling system, and development of a high-temperature illumination blackbody.

  16. Advanced materials based on carbon nanotube arrays, yarns and papers

    NASA Astrophysics Data System (ADS)

    Bradford, Phlip David

    Carbon nanotubes have hundreds of potential applications but require innovative processing techniques to manipulate the microscopic carbon dust into useful devices and products. This thesis describes efforts to process carbon nanotubes (CNTs) using novel methods with the goals of: (1) improving the properties of energy absorbing and composite carbon nanotube materials and (2) increasing understanding of fundamental structure-property relationships within these materials. Millimeter long CNTs, in the form of arrays, yarns and papers, were used to produce energy absorbing foams and high volume fraction CNT composites. Vertically aligned CNT arrays were grown on silicon substrates using chemical vapor deposition (CVD) of ethylene gas over iron nano-particles. The low density, millimeter thick arrays were tested under compression as energy absorbing foams. With additional CVD processing steps, it was possible to tune the compressive properties of the arrays. After the longest treatment, the compressive strength of the arrays was increased by a factor of 35 with a density increase of only six fold, while also imparting recovery from compression to the array. Microscopy revealed that the post-synthesis CVD treatment increased the number of CNT walls through an epitaxial type radial growth on the surface of the as-grown tubes. The increase in tube radius and mutual support between nanotubes explained the increases in compressive strength while an increase in nanotube roughness was proposed as the morphological change responsible for recovery in the array. Carbon nanotube yarns were used as the raw material for macroscopic textile preforms with a multi-level hierarchical carbon nanotube (CNT) structure: nanotubes, bundles, spun single yarns, plied yarns and 3-D braids. In prior tensile tests, composites produced from the 3-D braids exhibited unusual mechanical behavior effects. The proposed physical hypotheses explained those effects by molecular level interactions and

  17. Thermal Analysis and Correlation of the Mars Odyssey Spacecraft's Solar Array During Aerobraking Operations

    NASA Technical Reports Server (NTRS)

    Dec, John A.; Gasbarre, Joseph F.; George, Benjamin E.

    2002-01-01

    The Mars Odyssey spacecraft made use of multipass aerobraking to gradually reduce its orbit period from a highly elliptical insertion orbit to its final science orbit. Aerobraking operations provided an opportunity to apply advanced thermal analysis techniques to predict the temperature of the spacecraft's solar array for each drag pass. Odyssey telemetry data was used to correlate the thermal model. The thermal analysis was tightly coupled to the flight mechanics, aerodynamics, and atmospheric modeling efforts being performed during operations. Specifically, the thermal analysis predictions required a calculation of the spacecraft's velocity relative to the atmosphere, a prediction of the atmospheric density, and a prediction of the heat transfer coefficients due to aerodynamic heating. Temperature correlations were performed by comparing predicted temperatures of the thermocouples to the actual thermocouple readings from the spacecraft. Time histories of the spacecraft relative velocity, atmospheric density, and heat transfer coefficients, calculated using flight accelerometer and quaternion data, were used to calculate the aerodynamic heating. During aerobraking operations, the correlations were used to continually update the thermal model, thus increasing confidence in the predictions. This paper describes the thermal analysis that was performed and presents the correlations to the flight data.

  18. Advanced array techniques for unattended ground sensor applications

    NASA Astrophysics Data System (ADS)

    Followill, Fred E.; Wolford, James K.; Candy, James V.

    1997-07-01

    Sensor arrays offer opportunities to beamform, and time- frequency analyses offer additional insights to the wavefield data. Data collected while monitoring three different sources with unattended ground sensors in a 16- element, small-aperture (approximately 5 meters) geophone array are used as examples of model-based seismic signal processing on actual geophone array data. The three sources monitored were: (Source 01). A frequency-modulated chirp of an electromechanical shaker mounted on a floor of an underground bunker. Three 60-second time-windows corresponding to (a) 50 Hz to 55 Hz sweep, (b) 60 Hz to 70 Hz sweep, and (c) 80 Hz to 90 Hz sweep. (Source 02). A single transient impact of a hammer striking the floor of the bunker. Twenty seconds of data (with the transient event approximately mid-point in the time window). (Source 11). The transient event of a diesel generator turning on, including a few seconds before the `turn-on time' and a few seconds after the generator reaches `steady-state conditions'. The high-frequency seismic array was positioned at the surface of the ground at a distance of 150 meters (North) of the underground bunker. Four Y-shaped subarrays (each with 2-meter apertures) in a Y-shaped pattern (with a 6-meter aperture) using a total of 163-component, high- frequency geophones were deployed. These 48 channels of seismic data were recorded at 6000 and 12000 samples per second on 16-bit data loggers. Representative examples of the data and analyses illustrate the results of this experiment.

  19. Advanced array techniques for unattended ground sensor applications

    SciTech Connect

    Followill, F.E.; Wolford, J.K.; Candy, J.V.

    1997-05-06

    Sensor arrays offer opportunities to beam form, and time-frequency analyses offer additional insights to the wavefield data. Data collected while monitoring three different sources with unattended ground sensors in a 16-element, small-aperture (approximately 5 meters) geophone array are used as examples of model-based seismic signal processing on actual geophone array data. The three sources monitored were: (Source 01). A frequency-modulated chirp of an electromechanical shaker mounted on the floor of an underground bunker. Three 60-second time-windows corresponding to (a) 50 Hz to 55 Hz sweep, (b) 60 Hz to 70 Hz sweep, and (c) 80 Hz to 90 Hz sweep. (Source 02). A single transient impact of a hammer striking the floor of the bunker. Twenty seconds of data (with the transient event approximately mid-point in the time window.(Source 11)). The transient event of a diesel generator turning on, including a few seconds before the turn-on time and a few seconds after the generator reaches steady-state conditions. The high-frequency seismic array was positioned at the surface of the ground at a distance of 150 meters (North) of the underground bunker. Four Y-shaped subarrays (each with 2-meter apertures) in a Y-shaped pattern (with a 6-meter aperture) using a total of 16 3-component, high-frequency geophones were deployed. These 48 channels of seismic data were recorded at 6000 and 12000 samples per second on 16-bit data loggers. Representative examples of the data and analyses illustrate the results of this experiment.

  20. Development of High Efficiency (14%) Solar Cell Array Module

    NASA Technical Reports Server (NTRS)

    Iles, P. A.; Khemthong, S.; Olah, S.; Sampson, W. J.; Ling, K. S.

    1979-01-01

    High efficiency solar cells required for the low cost modules was developed. The production tooling for the manufacture of the cells and modules was designed. The tooling consisted of: (1) back contact soldering machine; (2) vacuum pickup; (3) antireflective coating tooling; and (4) test fixture.

  1. Energy requirement for the production of silicon solar arrays

    NASA Technical Reports Server (NTRS)

    Lindmayer, J.; Wihl, M.; Scheinine, A.; Morrison, A.

    1977-01-01

    An assessment of potential changes and alternative technologies which could impact the photovoltaic manufacturing process is presented. Topics discussed include: a multiple wire saw, ribbon growth techniques, silicon casting, and a computer model for a large-scale solar power plant. Emphasis is placed on reducing the energy demands of the manufacturing process.

  2. Solar-Array Substrate From Glass-Reinforced Concrete

    NASA Technical Reports Server (NTRS)

    Eirls, J. L.

    1985-01-01

    Design elminiates glass superstrate and associated metal framing. Panel has two trapezoidal stiffening ribs for structural support. Strategic placement of ribs with embedded support tubes (standard PVC tubing) minimizes bending moments and resulting stresses produced by installation and windloads. Glass-reinforced concrete panel has smooth flat surface suitable for solar substrate and includes structural bracing for rigidity and design adaptable to mass production.

  3. Advanced solar concentrator mass production, operation, and maintenance cost assessment

    NASA Technical Reports Server (NTRS)

    Niemeyer, W. A.; Bedard, R. J.; Bell, D. M.

    1981-01-01

    The object of this assessment was to estimate the costs of the preliminary design at: production rates of 100 to 1,000,000 concentrators per year; concentrators per aperture diameters of 5, 10, 11, and 15 meters; and various receiver/power conversion package weights. The design of the cellular glass substrate Advanced Solar Concentrator is presented. The concentrator is an 11 meter diameter, two axis tracking, parabolic dish solar concentrator. The reflective surface of this design consists of inner and outer groups of mirror glass/cellular glass gores.

  4. Polarization Calibration of the Advanced Technology Solar Telescope

    NASA Astrophysics Data System (ADS)

    Elmore, D. F.

    2014-10-01

    The Advanced Technology Solar Telescope (ATST) will be the World's largest solar polarimeter with a number of polarimetric instruments simultaneously sharing the ATST light beam. Polarization calibration requires determination of the polarization properties of the telescope optics that are shared by all instruments and the polarization response of each instrument. Hundreds of parameters are required to fully specify the telescope optics but by grouping successive optical elements separated at the Gregorian focus, the elevation rotation, and the Coudé - azimuth rotation and performing calibrations over the course of a day, it is possible to infer the polarization properties of each of the groups, and the instruments themselves with many fewer parameters.

  5. Solar Power Satellite Development: Advances in Modularity and Mechanical Systems

    NASA Technical Reports Server (NTRS)

    Belvin, W. Keith; Dorsey, John T.; Watson, Judith J.

    2010-01-01

    Space solar power satellites require innovative concepts in order to achieve economically and technically feasible designs. The mass and volume constraints of current and planned launch vehicles necessitate highly efficient structural systems be developed. In addition, modularity and in-space deployment will be enabling design attributes. This paper reviews the current challenges of launching and building very large space systems. A building block approach is proposed in order to achieve near-term solar power satellite risk reduction while promoting the necessary long-term technology advances. Promising mechanical systems technologies anticipated in the coming decades including modularity, material systems, structural concepts, and in-space operations are described

  6. solar thermal power systems advanced solar thermal technology project, advanced subsystems development

    NASA Technical Reports Server (NTRS)

    1979-01-01

    The preliminary design for a prototype small (20 kWe) solar thermal electric generating unit was completed, consisting of several subsystems. The concentrator and the receiver collect solar energy and a thermal buffer storage with a transport system is used to provide a partially smoothed heat input to the Stirling engine. A fossil-fuel combustor is included in the receiver designs to permit operation with partial or no solar insolation (hybrid). The engine converts the heat input into mechanical action that powers a generator. To obtain electric power on a large scale, multiple solar modules will be required to operate in parallel. The small solar electric power plant used as a baseline design will provide electricity at remote sites and small communities.

  7. Maximizing Solar Energy Capture Through Multi-Azimuth PV Arrays

    NASA Astrophysics Data System (ADS)

    Dahl, T. S.

    2013-12-01

    By orienting photovoltaic (PV) arrays in multiple directions, significantly greater energy capture can be realized in high latitude locations. Conventional wisdom dictates orienting PV panels south (in the northern hemisphere), but multi-azimuth arrays can confer several advantages during the summer months: - Nearly even power production over a large part of the day (20+ hours) - Reduced issues with power quality in grid interactive systems - Support higher loads in independent, off-grid systems - Reduced energy storage (battery) requirements in off-grid systems This poster will present two multi-azimuth systems, one a grid-interactive system deployed at Summit Station, Greenland; the second an independent, off-grid system supporting a science project near Toolik Field Station, Alaska.

  8. A summary report on the Flat-Plate Solar Array Project Workshop on Transparent Conducting Polymers

    NASA Technical Reports Server (NTRS)

    Kachare, R.; Moacanin, J.

    1985-01-01

    The proceedings and technical discussions of a workshop on Transparent Conducting Polymers (TCP) for solar cell applications are reported. This is in support of the Device Research Task of the Flat-Flate Solar Array Project. The workshop took place on January 11 and 12, 1985, in Santa Barbara, California. Participants included university and industry researchers. The discussions focused on the electronic and optical properties of TCP, and on experimental issues and problems that should be addressed for high-efficiency solar cell application.

  9. Advances in lenticular lens arrays for visual display

    NASA Astrophysics Data System (ADS)

    Johnson, R. Barry; Jacobsen, Gary A.

    2005-08-01

    Lenticular lens arrays are widely used in the printed display industry and in specialized applications of electronic displays. In general, lenticular arrays can create from interlaced printed images such visual effects as 3-D, animation, flips, morph, zoom, or various combinations. The use of these typically cylindrical lens arrays for this purpose began in the late 1920's. The lenses comprise a front surface having a spherical crosssection and a flat rear surface upon where the material to be displayed is proximately located. The principal limitation to the resultant image quality for current technology lenticular lenses is spherical aberration. This limitation causes the lenticular lens arrays to be generally thick (0.5 mm) and not easily wrapped around such items as cans or bottles. The objectives of this research effort were to develop a realistic analytical model, to significantly improve the image quality, to develop the tooling necessary to fabricate lenticular lens array extrusion cylinders, and to develop enhanced fabrication technology for the extrusion cylinder. It was determined that the most viable cross-sectional shape for the lenticular lenses is elliptical. This shape dramatically improves the image quality. The relationship between the lens radius, conic constant, material refractive index, and thickness will be discussed. A significant challenge was to fabricate a diamond-cutting tool having the proper elliptical shape. Both true elliptical and pseudo-elliptical diamond tools were designed and fabricated. The plastic sheets extruded can be quite thin (< 0.25 mm) and, consequently, can be wrapped around cans and the like. Fabrication of the lenticular engraved extrusion cylinder required remarkable development considering the large physical size and weight of the cylinder, and the tight mechanical tolerances associated with the lenticular lens molds cut into the cylinder's surface. The development of the cutting tool and the lenticular engraved

  10. Advanced Silicon Solar Cell Device Physics and Design

    NASA Astrophysics Data System (ADS)

    Deceglie, Michael Gardner

    A fundamental challenge in the development and deployment of solar photovoltaic technology is a reduction in cost enabling direct competition with fossil-fuel-based energy sources. A key driver in this cost reduction is optimized device efficiency, because increased energy output leverages all photovoltaic system costs, from raw materials and module manufacturing to installation and maintenance. To continue progress toward higher conversion efficiencies, solar cells are being fabricated with increasingly complex designs, including engineered nanostructures, heterojunctions, and novel contacting and passivation schemes. Such advanced designs require a comprehensive and unified understanding of the optical and electrical device physics at the microscopic scale. This thesis focuses on a microscopic understanding of solar cell optoelectronic performance and its impact on cell optimization. We consider this in three solar cell platforms: thin-film crystalline silicon, amorphous/crystalline silicon heterojunctions, and thin-film cells with nanophotonic light trapping. The work described in this thesis represents a powerful design paradigm, based on a detailed physical understanding of the mechanisms governing solar cell performance. Furthermore, we demonstrate the importance of understanding not just the individual mechanisms, but also their interactions. Such an approach to device optimization is critical for the efficiency and competitiveness of future generations of solar cells.

  11. Astronaut Story Musgrave during deployment of solar array panels on HST

    NASA Technical Reports Server (NTRS)

    1993-01-01

    Astronaut F. Story Musgrave moves about in the Space Shuttle Endeavour's cargo bay during the deployment of the solar array panels on the Hubble Space Telescope (HST) during the final of five STS-61 space walks. The left hand of Astronaut Jeffrey A. Hoffman appears at lower left corner.

  12. Flat Plate Solar Array Project: Proceedings of the 20th Project Integration Meeting

    NASA Technical Reports Server (NTRS)

    Mcdonald, R. R.

    1982-01-01

    Progress made by the Flat-Plate Solar Array Project during the period November 1981 to April 1982 is reported. Project analysis and integration, technology research in silicon material, large-area silicon sheet and environmental isolation, cell and module formation, engineering sciences, and module performance and failure analysis are covered.

  13. Low-cost solar array project and Proceedings of the 15th Project Integration Meeting

    NASA Technical Reports Server (NTRS)

    1980-01-01

    Progress made by the Low-Cost Solar Array Project during the period December 1979 to April 1980 is described. Project analysis and integration, technology development in silicon material, large area silicon sheet and encapsulation, production process and equipment development, engineering, and operation are included.

  14. Impact of LDEF photovoltaic experiment findings upon spacecraft solar array design and development requirements

    NASA Technical Reports Server (NTRS)

    Young, Leighton E.

    1993-01-01

    Photovoltaic cells (solar cells) and other solar array materials were flown in a variety of locations on the Long Duration Exposure Facility (LDEF). With respect to the predicted leading edge, solar array experiments were located at 0 degrees (row 9), 30 degrees (row 8) and 180 degrees (row 3). Postflight estimates of location of the experiments with respect to the velocity vector add 8.1 degrees to these values. Experiments were also located on the Earth end of the LDEF longitudinal axis. Types and magnitudes of detrimental effects differ between the locations with some commonality. Postflight evaluation of the solar array experiments reveal that some components/materials are very resistant to the environment to which they were exposed while others need protection, modification, or replacement. Interaction of materials with atomic oxygen (AO), as an area of major importance, was dramatically demonstrated by LDEF results. Information gained from the LDEF flight allows array developers to set new requirements for on-going and future technology and flight component development.

  15. Atomic Oxygen Exposure of Polyimide Foam for International Space Station Solar Array Wing Blanket Box

    NASA Technical Reports Server (NTRS)

    Finckenor, M. M.; Albyn, K. C.; Watts, E. W.

    2006-01-01

    Onorbit photos of the International Space Station (ISS) solar array blanket box foam pad assembly indicate degradation of the Kapton film covering the foam, leading to atomic oxygen (AO) exposure of the foam. The purpose of this test was to determine the magnitude of particulate generation caused by low-Earth orbital environment exposure of the foam and also by compression of the foam during solar array wing retraction. The polyimide foam used in the ISS solar array wing blanket box assembly is susceptible to significant AO erosion. The foam sample in this test lost one-third of its mass after exposure to the equivalent of 22 mo onorbit. Some particulate was generated by exposure to simulated orbital conditions and the simulated solar array retraction (compression test). However, onorbit, these particles would also be eroded by AO. The captured particles were generally <1 mm, and the particles shaken free of the sample had a maximum size of 4 mm. The foam sample maintained integrity after a compression load of 2.5 psi.

  16. Assessment of low-cost manufacturing process sequences. [photovoltaic solar arrays

    NASA Technical Reports Server (NTRS)

    Chamberlain, R. G.

    1979-01-01

    An extensive research and development activity to reduce the cost of manufacturing photovoltaic solar arrays by a factor of approximately one hundred is discussed. Proposed and actual manufacturing process descriptions were compared to manufacturing costs. An overview of this methodology is presented.

  17. Study of multi-kilowatt solar arrays for Earth orbit applications

    NASA Technical Reports Server (NTRS)

    Patterson, R. E.

    1983-01-01

    A miniaturized Cassegrainian concentrator (MCC) solar array concept is being developed with the objective of significantly reducing the recurring cost of multikilowatt solar arrays. The desired cost reduction is obtained as a result of using very small high efficiency solar cells in conjuction with low cost optics. The MCC single element concept incident slar radiation is reflected rom a primary parabolic reflector to a secondary hyperbolic reflector and finally to a 4 millimeter diameter solar cell. A light catcher cone is used to improve off axis performance. The solar cell is mounted to a heat fin. An element is approximately 13 millimeters thick which permits efficient launch stowage of the concentrator system panels without complex optical component deployments or retractions. The MCC elements are packed in bays within graphite epoxy frames and are electrically connected into appropriate series-parallel circuits. A MCC sngle element with a 21 sq cm entrance aperture and a 20 efficient, 0.25 sq cm gallium arsenide solar cell has the same power output as 30 sq cm of 11-percent efficiency (at 68 C) silicon solar cells.

  18. Circuit transients due to negative bias arcs on a high-voltage solar array in low Earth orbit

    NASA Technical Reports Server (NTRS)

    Metz, R. N.

    1985-01-01

    Arcing to negatively biased, exposed solar cell interconnects on solar arrays placed in plasma environments was established. Arcing, however, may cause damaging interference with the operation of electrical power systems in spacecraft planned to be driven with high-voltage solar arrays. An analytical model was developed to estimate the effects of netagive bias arcs on solar array power system performance. Solar cell characteristics, plasma interactions, and power system features are modeled by a linear, lumped element transient circuit, and the time domain equations are solved. Numerical results for solar array common mode and load voltage transients are calculated for typical conditions. Acceptable load transients are found for a range of arc current amplitudes and time constants.

  19. Chemical Vapor Deposition for Ultra-lightweight Thin-film Solar Arrays for Space

    NASA Technical Reports Server (NTRS)

    Hepp, Aloysius F.; Raffaelle, Ryne P.; Banger, Kulbinder K.; Jin, Michael H.; Lau, Janice E.; Harris, Jerry D.; Cowen, Jonathan E.; Duraj, Stan A.

    2002-01-01

    The development of thin-film solar cells on flexible, lightweight, space-qualified substrates provides an attractive cost solution to fabricating solar arrays with high specific power, (W/kg). The use of a polycrystalline chalcopyrite absorber layer for thin film solar cells is considered as the next generation photovoltaic devices. A key technical issues outlined in the 2001 U.S. Photovoltaic Roadmap, is the need to develop low cost, high throughput manufacturing for high-efficiency thin film solar cells. At NASA GRC we have focused on the development of new single-source-precursors (SSPs) and their utility to deposit the chalcopyrite semi-conducting layer (CIS) onto flexible substrates for solar cell fabrication. The syntheses and thermal modulation of SSPs via molecular engineering is described. Thin-film fabrication studies demonstrate the SSPs can be used in a spray CVD process, for depositing CIS at reduced temperatures, which display good electrical properties, suitable for PV devices.

  20. Inorganic/organic hybrid solar cells: optimal carrier transport in vertically aligned silicon nanowire arrays

    NASA Astrophysics Data System (ADS)

    Sato, Keisuke; Dutta, Mrinal; Fukata, Naoki

    2014-05-01

    Inorganic/organic hybrid radial heterojunction solar cells that combine vertically-aligned n-type silicon nanowires (SiNWs) with poly(3,4-ethylenedioxythiophene):poly(styrene-sulfonate) (PEDOT:PSS) have great potential for replacing commercial Si solar cells. The chief advantage of such solar cells is that they exhibit higher absorbance for a given thickness than commercial Si solar cells, due to incident light-trapping within the NW arrays, thus enabling lower-cost solar cell production. We report herein on the effects of NW length, annealing and surface electrode on the device performance of SiNW/PEDOT:PSS hybrid radial heterojunction solar cells. The power conversion efficiency (PCE) of the obtained SiNW/PEDOT:PSS hybrid solar cells can be optimized by tuning the thickness of the surface electrode, and the etching conditions during NW formation and post-annealing. The PCE of 9.3% is obtained by forming efficient transport pathways for photogenerated charge carriers to electrodes. Our approach is a significant contribution to design of high-performance and low-cost inorganic/organic hybrid heterojunction solar cells.Inorganic/organic hybrid radial heterojunction solar cells that combine vertically-aligned n-type silicon nanowires (SiNWs) with poly(3,4-ethylenedioxythiophene):poly(styrene-sulfonate) (PEDOT:PSS) have great potential for replacing commercial Si solar cells. The chief advantage of such solar cells is that they exhibit higher absorbance for a given thickness than commercial Si solar cells, due to incident light-trapping within the NW arrays, thus enabling lower-cost solar cell production. We report herein on the effects of NW length, annealing and surface electrode on the device performance of SiNW/PEDOT:PSS hybrid radial heterojunction solar cells. The power conversion efficiency (PCE) of the obtained SiNW/PEDOT:PSS hybrid solar cells can be optimized by tuning the thickness of the surface electrode, and the etching conditions during NW formation and