Transient analysis of an HTS DC power cable with an HVDC system
NASA Astrophysics Data System (ADS)
Dinh, Minh-Chau; Ju, Chang-Hyeon; Kim, Jin-Geun; Park, Minwon; Yu, In-Keun; Yang, Byeongmo
2013-11-01
The operational characteristics of a superconducting DC power cable connected to a highvoltage direct current (HVDC) system are mainly concerned with the HVDC control and protection system. To confirm how the cable operates with the HVDC system, verifications using simulation tools are needed. This paper presents a transient analysis of a high temperature superconducting (HTS) DC power cable in connection with an HVDC system. The study was conducted via the simulation of the HVDC system and a developed model of the HTS DC power cable using a real time digital simulator (RTDS). The simulation was performed with some cases of short circuits that may have caused system damage. The simulation results show that during the faults, the quench did not happen with the HTS DC power cable because the HVDC controller reduced some degree of the fault current. These results could provide useful data for the protection design of a practical HVDC and HTS DC power cable system.
NASA Astrophysics Data System (ADS)
Al-Taie, A.; Graber, L.; Pamidi, S. V.
2017-12-01
Opportunities for applications of high temperature superconducting (HTS) DC power cables for long distance power transmission in increasing the reliability of the electric power grid and to enable easier integration of distributed renewable sources into the grid are discussed. The gaps in the technology developments both in the superconducting cable designs and cryogenic systems as well as power electronic devices are identified. Various technology components in multi-terminal high voltage DC power transmission networks and the available options are discussed. The potential of ongoing efforts in the development of superconducting DC transmission systems is discussed.
NASA Astrophysics Data System (ADS)
Kumagai, Daisuke; Ohsaki, Hiroyuki; Tomita, Masaru
2016-12-01
A superconducting power cable has merits of a high power transmission capacity, transmission losses reduction, a compactness, etc., therefore, we have been studying the feasibility of applying superconducting power cables to DC electric railway feeding systems. However, a superconducting power cable is required to be cooled down and kept at a very low temperature, so it is important to reveal its thermal and cooling characteristics. In this study, electric circuit analysis models of the system and thermal analysis models of superconducting cables were constructed and the system behaviors were simulated. We analyzed the heat generation by a short circuit accident and transient temperature distribution of the cable to estimate the value of temperature rise and the time required from the accident. From these results, we discussed a feasibility of superconducting cables for DC electric railway feeding systems. The results showed that the short circuit accident had little impact on the thermal condition of a superconducting cable in the installed system.
The Development and Demonstration of a 360m/10 kA HTS DC Power Cable
NASA Astrophysics Data System (ADS)
Xiao, Liye
With the quick development of renewable energy, it is expected that the electric power from renewable energy would be the dominant one for the future power grid. Due to the specialty of the renewable energy, the HVDC power transmission would be very useful for the transmission of electric power from renewable energy. DC power cable made of High Tc Superconductor (HTS) would be a possible alternative for the construction of HVDC power transmission system. In this chapter, we report the development and demonstration of a 360 m/10 kA HTS DC power cable and the test results.
Application of Superconducting Power Cables to DC Electric Railway Systems
NASA Astrophysics Data System (ADS)
Ohsaki, Hiroyuki; Lv, Zhen; Sekino, Masaki; Tomita, Masaru
For novel design and efficient operation of next-generation DC electric railway systems, especially for their substantial energy saving, we have studied the feasibility of applying superconducting power cables to them. In this paper it is assumed that a superconducting power cable is applied to connect substations supplying electric power to trains. An analysis model line was described by an electric circuit, which was analyzed with MATLAB-Simulink. From the calculated voltages and currents of the circuit, the regenerative brake and the energy losses were estimated. In addition, assuming the heat loads of superconducting power cables and the cryogenic efficiency, the energy saving of the total system was evaluated. The results show that the introduction of superconducting power cables could achieve the improved use of regenerative brake, the loss reduction, the decreased number of substations, the reduced maintenance, etc.
NASA Astrophysics Data System (ADS)
Ohsaki, H.; Matsushita, N.; Koseki, T.; Tomita, M.
2014-05-01
The application of superconducting power cables to DC electric railway systems has been studied. It could leads to an effective use of regenerative brake, improved energy efficiency, effective load sharing among the substations, etc. In this study, an electric circuit model of a DC feeding system is built and numerical simulation is carried out using MATLAB-Simulink software. A modified electric circuit model with an AC power grid connection taken into account is also created to simulate the influence of the grid connection. The analyses have proved that a certain amount of energy can be conserved by introducing superconducting cables, and that electric load distribution and concentration among the substations depend on the substation output voltage distribution.
NASA Astrophysics Data System (ADS)
Tomita, Masaru
The development of a superconducting cable for railways has commenced, assuming that a DC transmission cable will be used for electric trains. The cable has been fabricated based on the results of current testing of a superconducting wire, and various evaluation tests have been performed to determine the characteristics of the cable. A superconducting transmission cable having zero electrical resistance and suitable for railway use is expected to enhance regeneration efficiency, reduce power losses, achieve load leveling and integration of sub-stations, and reduce rail potential.
NASA Astrophysics Data System (ADS)
Hwang, Jae-Sang; Seong, Jae-Kyu; Shin, Woo-Ju; Lee, Jong-Geon; Cho, Jeon-Wook; Ryoo, Hee-Suk; Lee, Bang-Wook
2013-11-01
High temperature superconducting (HTS) cable has been paid much attention due to its high efficiency and high current transportation capability, and it is also regarded as eco-friendly power cable for the next generation. Especially for DC HTS cable, it has more sustainable and stable properties compared to AC HTS cable due to the absence of AC loss in DC HTS cable. Recently, DC HTS cable has been investigated competitively all over the world, and one of the key components of DC HTS cable to be developed is a cable joint box considering HVDC environment. In order to achieve the optimum insulation design of the joint box, analysis of DC electric field distribution of the joint box is a fundamental process to develop DC HTS cable. Generally, AC electric field distribution depends on relative permittivity of dielectric materials but in case of DC, electrical conductivity of dielectric material is a dominant factor which determines electric field distribution. In this study, in order to evaluate DC electric field characteristics of the joint box for DC HTS cable, polypropylene laminated paper (PPLP) specimen has been prepared and its DC electric field distribution was analyzed based on the measurement of electrical conductivity of PPLP in liquid nitrogen (LN2). Electrical conductivity of PPLP in LN2 has not been reported yet but it should be measured for DC electric field analysis. The experimental works for measuring electrical conductivity of PPLP in LN2 were presented in this paper. Based on the experimental works, DC electric field distribution of PPLP specimen was fully analyzed considering the steady state and the transient state of DC. Consequently, it was possible to determine the electric field distribution characteristics considering different DC applying stages including DC switching on, DC switching off and polarity reversal conditions.
High-Voltage, Low-Power BNC Feedthrough Terminator
NASA Technical Reports Server (NTRS)
Bearden, Douglas
2012-01-01
This innovation is a high-voltage, lowpower BNC (Bayonet Neill-Concelman) feedthrough that enables the user to terminate an instrumentation cable properly while connected to a high voltage, without the use of a voltage divider. This feedthrough is low power, which will not load the source, and will properly terminate the instrumentation cable to the instrumentation, even if the cable impedance is not constant. The Space Shuttle Program had a requirement to measure voltage transients on the orbiter bus through the Ground Lightning Measurement System (GLMS). This measurement has a bandwidth requirement of 1 MHz. The GLMS voltage measurement is connected to the orbiter through a DC panel. The DC panel is connected to the bus through a nonuniform cable that is approximately 75 ft (approximately equal to 23 m) long. A 15-ft (approximately equal to 5-m), 50-ohm triaxial cable is connected between the DC panel and the digitizer. Based on calculations and simulations, cable resonances and reflections due to mismatched impedances of the cable connecting the orbiter bus and the digitizer causes the output not to reflect accurately what is on the bus. A voltage divider at the DC panel, and terminating the 50-ohm cable properly, would eliminate this issue. Due to implementation issues, an alternative design was needed to terminate the cable properly without the use of a voltage divider. Analysis shows how the cable resonances and reflections due to the mismatched impedances of the cable connecting the orbiter bus and the digitizer causes the output not to reflect accurately what is on the bus. After simulating a dampening circuit located at the digitizer, simulations were performed to show how the cable resonances were dampened and the accuracy was improved significantly. Test cables built to verify simulations were accurate. Since the dampening circuit is low power, it can be packaged in a BNC feedthrough.
Development of a single-phase 30 m HTS power cable
NASA Astrophysics Data System (ADS)
Cho, Jeonwook; Bae, Joon-Han; Kim, Hae-Jong; Sim, Ki-Deok; Kim, Seokho; Jang, Hyun-Man; Lee, Chang-Young; Kim, Dong-Wook
2006-05-01
HTS power transmission cables appear to be the replacement and retrofitting of underground cables in urban areas and HTS power transmission cable offers a number of technical and economic merits compared to the normal conductor cable system. A 30 m long, single-phase 22.9 kV class HTS power transmission cable system has been developed by Korea Electrotechnology Research Institute (KERI), LS Cable Ltd., and Korea Institute of Machinery and Materials (KIMM), which is one of the 21st century frontier project in Korea since 2001. The HTS power cable has been developed, cooled down and tested to obtain realistic thermal and electrical data on HTS power cable system. The evaluation results clarified such good performance of HTS cable that DC critical current of the HTS cable was 3.6 kA and AC loss was 0.98 W/m at 1260 Arms and shield current was 1000 Arms. These results proved the basic properties for 22.9 kV HTS power cable. As a next step, we have been developing a 30 m, three-phase 22.9 kV, 50 MV A HTS power cable system and long term evaluation is in progress now.
Investigation of the Feasibility of a Superconducting Self-Healing DC Grid on a LNG Carrier
2015-06-21
art in High Temperature Superconductor technology is reviewed and an analytical approach of Superconducting DC Power Distribution on a power... Superconductors . I. INTRODUCTION During recent years, the usage of electrical power on- board vessels has grown exponentially. This fact, led...grid. When carrying DC current superconductors are perfectly lossless regardless of the cable length and the power rating of the line [1]. Also
77 FR 25729 - Notice of Issuance of Final Determination Concerning Certain Agilent Oscilloscopes
Federal Register 2010, 2011, 2012, 2013, 2014
2012-05-01
.... LIT. 7. AC line filter PCA that acts as the power manager; 8. Power supply; 9. Fan; 10. Bucket..., consisting of the fan, the AC Line Filter PCA, power supply, AC and DC cables, and wiring, is installed into... power cable on the front deck subassembly is connected to the AC line filter PCA on the rear deck...
46 CFR 116.202 - Plans and information required.
Code of Federal Regulations, 2011 CFR
2011-10-01
... Safety Center, 2100 2nd St. SW., Stop 7102, Washington, DC 20593-7102, in a written or electronic format... cables, bus-tie cables, feeders, and branch circuit cables; (vi) Power, lighting, and interior communication panelboards with number of circuits and rating of energy consuming devices; (vii) Type and...
46 CFR 116.202 - Plans and information required.
Code of Federal Regulations, 2012 CFR
2012-10-01
... Safety Center, 2100 2nd St. SW., Stop 7102, Washington, DC 20593-7102, in a written or electronic format... cables, bus-tie cables, feeders, and branch circuit cables; (vi) Power, lighting, and interior communication panelboards with number of circuits and rating of energy consuming devices; (vii) Type and...
Photovoltaic Power System and Power Distribution Demonstration for the Desert RATS Program
NASA Technical Reports Server (NTRS)
Colozza, Anthony; Jakupca, Ian; Mintz, Toby; Herlacher, Mike; Hussey, Sam
2012-01-01
A stand alone, mobile photovoltaic power system along with a cable deployment system was designed and constructed to take part in the Desert Research And Technology Studies (RATS) lunar surface human interaction evaluation program at Cinder Lake, Arizona. The power system consisted of a photovoltaic array/battery system. It is capable of providing 1 kW of electrical power. The system outputs were 48 V DC, 110 V AC, and 220 V AC. A cable reel with 200 m of power cable was used to provide power from the trailer to a remote location. The cable reel was installed on a small trailer. The reel was powered to provide low to no tension deployment of the cable. The cable was connected to the 220 V AC output of the power system trailer. The power was then converted back to 110 V AC on the cable deployment trailer for use at the remote site. The Scout lunar rover demonstration vehicle was used to tow the cable trailer and deploy the power cable. This deployment was performed under a number of operational scenarios, manned operation, remote operation and tele-robotically. Once deployed, the cable was used to provide power, from the power system trailer, to run various operational tasks at the remote location.
On the mechanism of charge transport in low density polyethylene
NASA Astrophysics Data System (ADS)
Upadhyay, Avnish K.; Reddy, C. C.
2017-08-01
Polyethylene based polymeric insulators, are being increasingly used in the power industry for their inherent advantages over conventional insulation materials. Specifically, modern power cables are almost made with these materials, replacing the mass-impregnated oil-paper cable technology. However, for ultra-high dc voltage applications, the use of these polymeric cables is hindered by ununderstood charge transport and accumulation. The conventional conduction mechanisms (Pool-Frenkel, Schottky, etc.) fail to track high-field charge transport in low density polyethylene, which is semi-crystalline in nature. Until now, attention was devoted mainly to the amorphous region of the material. In this paper, authors propose a novel mechanism for conduction in low density polyethylene, which could successfully track experimental results. As an implication, a novel, substantial relationship is established for electrical conductivity that could be effectively used for understanding conduction and breakdown in polyethylene, which is vital for successful development of ultra-high voltage dc cables.
Lunar Surface-to-Surface Power Transfer
NASA Technical Reports Server (NTRS)
Kerslake, Thomas W.
2007-01-01
A human lunar outpost, under NASA study for construction in the 2020's, has potential requirements to transfer electric power up to 50-kW across the lunar surface from 0.1 to 10-km distances. This power would be used to operate surface payloads located remotely from the outpost and/or outpost primary power grid. This paper describes concept designs for state-of-the-art technology power transfer subsystems including AC or DC power via cables, beamed radio frequency power and beamed laser power. Power transfer subsystem mass and performance are calculated and compared for each option. A simplified qualitative assessment of option operations, hazards, costs and technology needs is also described. Based on these concept designs and performance analyses, a DC power cabling subsystem is recommended to minimize subsystem mass and to minimize mission and programmatic costs and risks. Avenues for additional power transfer subsystem studies are recommended.
Power supply and pulsing strategies for the future linear colliders
NASA Astrophysics Data System (ADS)
Brogna, A. S.; Göttlicher, P.; Weber, M.
2012-02-01
The concept of the power delivery systems of the future linear colliders exploits the pulsed bunch structure of the beam in order to minimize the average current in the cables and the electronics and thus to reduce the material budget and heat dissipation. Although modern integrated circuit technologies are already available to design a low-power system, the concepts on how to pulse the front-end electronics and further reduce the power are not yet well understood. We propose a possible implementation of a power pulsing system based on a DC/DC converter and we choose the Analog Hadron Calorimeter as a specific example. The model features large switching currents of electronic modules in short time intervals to stimulate the inductive components along the cables and interconnections.
Sun, Tianjia; Xie, Xiang; Li, Guolin; Gu, Yingke; Deng, Yangdong; Wang, Zhihua
2012-11-01
This paper presents a wireless power transfer system for a motion-free capsule endoscopy inspection. Conventionally, a wireless power transmitter in a specifically designed jacket has to be connected to a strong power source with a long cable. To avoid the power cable and allow patients to walk freely in a room, this paper proposes a two-hop wireless power transfer system. First, power is transferred from a floor to a power relay in the patient's jacket via strong coupling. Next, power is delivered from the power relay to the capsule via loose coupling. Besides making patients much more conformable, the proposed techniques eliminate the sources of reliability issues arisen from the moving cable and connectors. In the capsule, it is critical to enhance the power conversion efficiency. This paper develops a switch-mode rectifier (rectifying efficiency of 93.6%) and a power combination circuit (enhances combining efficiency by 18%). Thanks to the two-hop transfer mechanism and the novel circuit techniques, this system is able to transfer an average power of 24 mW and a peak power of 90 mW from the floor to a 13 mm × 27 mm capsule over a distance of 1 m with the maximum dc-to-dc power efficiency of 3.04%.
NASA Astrophysics Data System (ADS)
Dinh, Minh-Chau; Ju, Chang-Hyeon; Kim, Sung-Kyu; Kim, Jin-Geun; Park, Minwon; Yu, In-Keun
2013-01-01
The combination of a high temperature superconducting DC power cable and a voltage source converter based HVDC (VSC-HVDC) creates a new option for transmitting power with multiple collection and distribution points for long distance and bulk power transmissions. It offers some greater advantages compared with HVAC or conventional HVDC transmission systems, and it is well suited for the grid integration of renewable energy sources in existing distribution or transmission systems. For this reason, a superconducting DC transmission system based HVDC transmission technologies is planned to be set up in the Jeju power system, Korea. Before applying this system to a real power system on Jeju Island, system analysis should be performed through a real time test. In this paper, a model-sized superconducting VSC-HVDC system, which consists of a small model-sized VSC-HVDC connected to a 2 m YBCO HTS DC model cable, is implemented. The authors have performed the real-time simulation method that incorporates the model-sized superconducting VSC-HVDC system into the simulated Jeju power system using Real Time Digital Simulator (RTDS). The performance analysis of the superconducting VSC-HVDC systems has been verified by the proposed test platform and the results were discussed in detail.
NASA Astrophysics Data System (ADS)
Dinh, Minh-Chau; Ju, Chang-Hyeon; Kim, Sung-Kyu; Kim, Jin-Geun; Park, Minwon; Yu, In-Keun
2012-08-01
The combination of a high temperature superconducting DC power cable and a voltage source converter based HVDC (VSC-HVDC) creates a new option for transmitting power with multiple collection and distribution points for long distance and bulk power transmissions. It offers some greater advantages compared with HVAC or conventional HVDC transmission systems, and it is well suited for the grid integration of renewable energy sources in existing distribution or transmission systems. For this reason, a superconducting DC transmission system based HVDC transmission technologies is planned to be set up in the Jeju power system, Korea. Before applying this system to a real power system on Jeju Island, system analysis should be performed through a real time test. In this paper, a model-sized superconducting VSC-HVDC system, which consists of a small model-sized VSC-HVDC connected to a 2 m YBCO HTS DC model cable, is implemented. The authors have performed the real-time simulation method that incorporates the model-sized superconducting VSC-HVDC system into the simulated Jeju power system using Real Time Digital Simulator (RTDS). The performance analysis of the superconducting VSC-HVDC systems has been verified by the proposed test platform and the results were discussed in detail.
NASA Astrophysics Data System (ADS)
Seo, In-jin; Choi, Won; Seong, Jae-gyu; Lee, Bang-wook; Koo, Ja-yoon
2014-08-01
It has been reported that the insulation design under DC stress is considered as one of the critical factors in determining the performance of high-voltage direct current (HVDC) superconducting cable. Therefore, it is fundamentally necessary to investigate the DC breakdown characteristics of the composite insulation system consisting of liquid nitrogen (LN2)/polypropylene-laminated-paper (PPLP). In particular, the insulation characteristics under DC polarity reversal condition should be verified to understand the polarity effect of the DC voltage considering the unexpected incidents taking place at line-commutated-converters (LCC) under service at a DC power grid. In this study, to examine the variation of DC electric field strength, the step voltage and polarity reversal breakdown tests are performed under DC stress. Also, we investigate the electric field distributions in a butt gap of the LN2/PPLP condition considering the DC polarity reversal by using simulation software.
1981-10-01
Chesaneake Division, Naval Facilities Engineering Command, Washington, DC) 34. "Strait of Belle Isle Crossing HVDC Transmission - Submarine Cable...phenomena; such as wind storm generated wave action, bottom currents, bottom mudslides, or seismic activity; as well as human activity, such as...engaging a cable. Ship anchors are used to develop holding power on the seafloor for mooring a floating body permanently or temporary on site. The major
NASA Technical Reports Server (NTRS)
Moores, Greg; Heller, R. P.; Sutanto, Surja; Dugal-Whitehead, Norma R.
1992-01-01
Unexpected and undesirable arcing on dc power systems can produce hazardous situations aboard space flights. The potential for fire and shock might exist in a situation where there is a broken conductor, a loose power connection, or a break in the insulation of the power cable. Such arcing has been found to be reproducible in a laboratory environment. Arcing tests show that the phenomena can last for several seconds and yet be undetectable by present protection schemes used in classical power relaying and remote power controller applications. This paper characterizes the arcing phenomena and suggests future research that is needed.
NASA Astrophysics Data System (ADS)
Wyman, M. T.; Kavet, R.; Klimley, A. P.
2016-02-01
There is an increasingly strong interest on a global scale in offshore renewable energy production and transportation. However, there is concern that the electromagnetic fields (EMF) produced by these underwater cables may alter the behavior and physiology of marine species. Despite this concern, few studies have investigated these effects in free-living species. In 2009, a 85 km long high-voltage DC (HVDC) power cable was placed within the San Francisco Bay, running parallel, then perpendicular to, the migration route of anadromous species moving from the inland river system to the oceans. In this study, we assess the impacts of this HVDC cable on the migration behaviors of EMF-sensitive fish, including juvenile salmonids (Chinook salmon, Oncorhynchus tshawytscha, and steelhead trout, Oncorhynchus mykiss) and adult green sturgeon, Acipenser medirostris. Acoustic telemetry techniques were used to track fish migration movements through the San Francisco Bay both before and after the cable was activated; individuals implanted with acoustic transmitters were detected on cross-channel hydrophone arrays at key locations in the system. Magnetic fields were surveyed and mapped at these locations using a transverse gradiometer, and models of the cable's magnetic field were developed that closely matched the empirically measured values. Here, we present our analyses on the relationships between migration-related behavioral metrics (e.g., percent of successful migrations, duration of migration, time spent near vs. far from cable location, etc.) and environmental parameters, such as cable activation and load level, local magnetic field levels, depth, and currents.
Corrosion study on high power feeding of telecomunication copper cable in 5 wt.% CaSO4.2H2O solution
NASA Astrophysics Data System (ADS)
Shamsudin, Shaiful Rizam; Hashim, Nabihah; Ibrahim, Mohd Saiful Bahri; Rahman, Muhammad Sayuzi Abdul; Idrus, Muhammad Amin; Hassan, Mohd Rezadzudin; Abdullah, Wan Razli Wan
2016-07-01
The studies were carried out to find out the best powering scheme over the copper telephone line. It was expected that the application of the higher power feeding could increase the data transfer and capable of providing the customer's satisfaction. To realize the application of higher remote power feeding, the potential of corrosion problem on Cu cables was studied. The natural corrosion behaviour of copper cable in the 0.5% CaSO4.2H2O solution was studied in term of open circuit potential for 30 days. The corrosion behaviour of higher power feeding was studied by the immersion and the planned interval test to determine the corrosion rate as well as the effect of voltage magnitudes and the current scheme i.e. positive direct (DC+) and alternating current (AC) at about 0.40 ± 0.01 mA/ cm2 current density. In the immersion test, both DC+ and AC scheme showed the increasing of feeding voltage magnitude has increased the corrosion rate of Cu samples starting from 60 to 100 volts. It was then reduced at about 100 - 120 volts which may due to the passive and transpassive mechanism. The corrosion rate was slowly reduced further from 120 to 200 volts. Visually, the positively charged of Cu cable was seems susceptible to severe corrosion, while AC scheme exhibited a slight corrosion reaction on the surface. However, the planned interval test and XRD results showed the corrosion activity of the copper cable in the studied solution was a relatively slow process and considered not to be corroded as a partially protective scale of copper oxide formed on the surface.
Dynamic characteristics of a 20 kHz resonant power system - Fault identification and fault recovery
NASA Technical Reports Server (NTRS)
Wasynczuk, O.
1988-01-01
A detailed simulation of a dc inductor resonant driver and receiver is used to demonstrate the transient characteristics of a 20 kHz resonant power system during fault and overload conditions. The simulated system consists of a dc inductor resonant inverter (driver), a 50-meter transmission cable, and a dc inductor resonant receiver load. Of particular interest are the driver and receiver performance during fault and overload conditions and on the recovery characteristics following removal of the fault. The information gained from these studies sets the stage for further work in fault identification and autonomous power system control.
Hargrove, Douglas L.
2004-09-14
A portable, hand-held meter used to measure direct current (DC) attenuation in low impedance electrical signal cables and signal attenuators. A DC voltage is applied to the signal input of the cable and feedback to the control circuit through the signal cable and attenuators. The control circuit adjusts the applied voltage to the cable until the feedback voltage equals the reference voltage. The "units" of applied voltage required at the cable input is the system attenuation value of the cable and attenuators, which makes this meter unique. The meter may be used to calibrate data signal cables, attenuators, and cable-attenuator assemblies.
Feasibility study of a 270V dc flat cable aircraft electrical power distributed system
NASA Astrophysics Data System (ADS)
Musga, M. J.; Rinehart, R. J.
1982-01-01
This report documents the efforts of a one man-year feasibility study to evaluate the usage of flat conductors in place of conventional round wires for a 270 volt direct current aircraft power distribution system. This study consisted of designing electrically equivalent power distribution harnesses in flat conductor configurations for a currently operational military aircraft. Harness designs were established for installation in aircraft airframes which are: (1) All metal, or (2) All composite, or (3) a mixture of both. Flat cables have greater surface areas for heat transfer allowing higher current densities and therefore lighter weight conductors, than with round wires. Flat cables are less susceptible to electromagnetic effects. However, these positive factors are partially offset by installation and maintenance difficulties. This study concludes that the extent of these difficulties can be adequately limited with appropriate modification to present installation and maintenance practices. A comparative analysis of the flat and the round conductor power distribution harnesses was made for weight, cost, maintenance and reliability. The knowledge gained from the design and comparative analysis phases was used to generate design criteria for flat power cable harnesses and to identify and prioritize flat cable harness components and associated production tooling which require development.
High-Frequency ac Power-Distribution System
NASA Technical Reports Server (NTRS)
Hansen, Irving G.; Mildice, James
1987-01-01
Loads managed automatically under cycle-by-cycle control. 440-V rms, 20-kHz ac power system developed. System flexible, versatile, and "transparent" to user equipment, while maintaining high efficiency and low weight. Electrical source, from dc to 2,200-Hz ac converted to 440-V rms, 20-kHz, single-phase ac. Power distributed through low-inductance cables. Output power either dc or variable ac. Energy transferred per cycle reduced by factor of 50. Number of parts reduced by factor of about 5 and power loss reduced by two-thirds. Factors result in increased reliability and reduced costs. Used in any power-distribution system requiring high efficiency, high reliability, low weight, and flexibility to handle variety of sources and loads.
Very low noise AC/DC power supply systems for large detector arrays.
Arnaboldi, C; Baù, A; Carniti, P; Cassina, L; Giachero, A; Gotti, C; Maino, M; Passerini, A; Pessina, G
2015-12-01
In this work, we present the first part of the power supply system for the CUORE and LUCIFER arrays of bolometric detectors. For CUORE, it consists of AC/DC commercial power supplies (0-60 V output) followed by custom DC/DC modules (48 V input, ±5 V to ±13.5 V outputs). Each module has 3 floating and independently configurable output voltages. In LUCIFER, the AC/DC + DC/DC stages are combined into a commercial medium-power AC/DC source. At the outputs of both setups, we introduced filters with the aim of lowering the noise and to protect the following stages from high voltage spikes that can be generated by the energy stored in the cables after the release of accidental short circuits. Output noise is very low, as required: in the 100 MHz bandwidth the RMS level is about 37 μV(RMS) (CUORE setup) and 90 μV(RMS) (LUCIFER setup) at a load of 7 A, with a negligible dependence on the load current. Even more importantly, high frequency switching disturbances are almost completely suppressed. The efficiency of both systems is above 85%. Both systems are completely programmable and monitored via CAN bus (optically coupled).
49 CFR 232.603 - Design, interoperability, and configuration management requirements.
Code of Federal Regulations, 2010 CFR
2010-10-01
...: 1999; Revised 2002, 2007); (3) AAR S-4220, “ECP Cable-Based Brake DC Power Supply—Performance...; Revised: 2004); (7) AAR S-4260, “ECP Brake and Wire Distributed Power Interoperability Test Procedures...) Approval. A freight train or freight car equipped with an ECP brake system and equipment covered by the AAR...
2.45 GHz Rectenna Designed for Wireless Sensors Operating at 500 C
NASA Technical Reports Server (NTRS)
Ponchak, George E.; Schwartz, Zachary D.; Jordan, Jennifer L.; Downey, Alan N.; Neudeck, Philip G.
2004-01-01
High temperature wireless sensors that operate at 500 C are required for aircraft engine monitoring and performance improvement These sensors would replace currently used hard-wired sensors and lead to a substantial reduction in mass. However, even if the sensor output data is transmitted wirelessly to a receiver in the cooler part of the engine, and the associated cables are eliminated, DC power cables are still required to operate the sensors and power the wireless circuits. To solve this problem, NASA is developing a rectenna, a circuit that receives RF power and converts it to DC power. The rectenna would be integrated with the wireless sensor, and the RF transmitter that powers the rectenna would be located in the cooler part of the engine. In this way, no cables to or from the sensors are required. Rectennas haw been demonstrated at ambient room temperature, but to date, no high temperature rectennas haw been reported. In this paper, we report the first rectenna designed for 2.45 GHz operation at 500 C. The circuit consists of a microstrip dipole antenna, a stripline impedance matching circuit, and a stripline low pass filter to prevent transmission of higher harmonics created by the rectifying diode fabricated on an Alumina substrate. The rectifying diode is the gate to source junction of a 6H Sic MESFET and the capacitor and load resistor are chip elements that are each bonded to the Alumina substrate. Each element and the hybrid, rectenna circuit haw been characterized through 500 C.
The creation of high-temperature superconducting cables of megawatt range in Russia
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sytnikov, V. E., E-mail: vsytnikov@gmail.com; Bemert, S. E.; Krivetsky, I. V.
Urgent problems of the power industry in the 21st century require the creation of smart energy systems, providing a high effectiveness of generation, transmission, and consumption of electric power. Simultaneously, the requirements for controllability of power systems and ecological and resource-saving characteristics at all stages of production and distribution of electric power are increased. One of the decision methods of many problems of the power industry is the development of new high-efficiency electrical equipment for smart power systems based on superconducting technologies to ensure a qualitatively new level of functioning of the electric power industry. The intensive research and developmentmore » of new types of electrical devices based on superconductors are being carried out in many industrialized advanced countries. Interest in such developments has especially increased in recent years owing to the discovery of so-called high-temperature superconductors (HTS) that do not require complicated and expensive cooling devices. Such devices can operate at cooling by inexpensive and easily accessible liquid nitrogen. Taking into account the obvious advantages of superconducting cable lines for the transmission of large power flows through an electrical network, as compared with conventional cables, the Federal Grid Company of Unified Energy System (JSC FGC UES) initiated a research and development program including the creation of superconducting HTS AC and DC cable lines. Two cable lines for the transmitted power of 50 MVA/MW at 20 kV were manufactured and tested within the framework of the program.« less
The creation of high-temperature superconducting cables of megawatt range in Russia
NASA Astrophysics Data System (ADS)
Sytnikov, V. E.; Bemert, S. E.; Krivetsky, I. V.; Romashov, M. A.; Popov, D. A.; Fedotov, E. V.; Komandenko, O. V.
2015-12-01
Urgent problems of the power industry in the 21st century require the creation of smart energy systems, providing a high effectiveness of generation, transmission, and consumption of electric power. Simultaneously, the requirements for controllability of power systems and ecological and resource-saving characteristics at all stages of production and distribution of electric power are increased. One of the decision methods of many problems of the power industry is the development of new high-efficiency electrical equipment for smart power systems based on superconducting technologies to ensure a qualitatively new level of functioning of the electric power industry. The intensive research and development of new types of electrical devices based on superconductors are being carried out in many industrialized advanced countries. Interest in such developments has especially increased in recent years owing to the discovery of so-called high-temperature superconductors (HTS) that do not require complicated and expensive cooling devices. Such devices can operate at cooling by inexpensive and easily accessible liquid nitrogen. Taking into account the obvious advantages of superconducting cable lines for the transmission of large power flows through an electrical network, as compared with conventional cables, the Federal Grid Company of Unified Energy System (JSC FGC UES) initiated a research and development program including the creation of superconducting HTS AC and DC cable lines. Two cable lines for the transmitted power of 50 MVA/MW at 20 kV were manufactured and tested within the framework of the program.
Total Magnetic Field Signatures over Submarine HVDC Power Cables
NASA Astrophysics Data System (ADS)
Johnson, R. M.; Tchernychev, M.; Johnston, J. M.; Tryggestad, J.
2013-12-01
Mikhail Tchernychev, Geometrics, Inc. Ross Johnson, Geometrics, Inc. Jeff Johnston, Geometrics, Inc. High Voltage Direct Current (HVDC) technology is widely used to transmit electrical power over considerable distances using submarine cables. The most commonly known examples are the HVDC cable between Italy and Greece (160 km), Victoria-Tasmania (300 km), New Jersey - Long Island (82 km) and the Transbay cable (Pittsburg, California - San-Francisco). These cables are inspected periodically and their location and burial depth verified. This inspection applies to live and idle cables; in particular a survey company could be required to locate pieces of a dead cable for subsequent removal from the sea floor. Most HVDC cables produce a constant magnetic field; therefore one of the possible survey tools would be Marine Total Field Magnetometer. We present mathematical expressions of the expected magnetic fields and compare them with fields observed during actual surveys. We also compare these anomalies fields with magnetic fields produced by other long objects, such as submarine pipelines The data processing techniques are discussed. There include the use of Analytic Signal and direct modeling of Total Magnetic Field. The Analytic Signal analysis can be adapted using ground truth where available, but the total field allows better discrimination of the cable parameters, in particular to distinguish between live and idle cable. Use of a Transverse Gradiometer (TVG) allows for easy discrimination between cable and pipe line objects. Considerable magnetic gradient is present in the case of a pipeline whereas there is less gradient for the DC power cable. Thus the TVG is used to validate assumptions made during the data interpretation process. Data obtained during the TVG surveys suggest that the magnetic field of a live HVDC cable is described by an expression for two infinite long wires carrying current in opposite directions.
Detector Powering in the 21st Century Why stay stuck with the Good old 20th Century methods?
NASA Astrophysics Data System (ADS)
Dhawan, Satish; Sumner, Richard
Future Collider Physics Detectors are envisioned with large granularity but we have a power delivery problem unless we fill a large fraction of the detector volume with copper conductors. LHC detector electronics is powered by transporting direct current over distances of 30 to 150 meters. This is how Thomas Alva Edison powered his light bulb. For example, CMS ECAL uses 50 kiloamps at 2.5 volts, supplied over a cable set with a transmission efficiency of only 30%. The transmission loss becomes waste heat in the detector that has to be removed. We have been exploring methods to transmit the DC power at higher voltage (low current), reducing to the final low voltage (high current) using DC-DC converters. These converters must operate in high magnetic fields and high radiation levels. This requires rad hard components and non-magnetic (air core) inductors.
Multi-kw dc power distribution system study program
NASA Technical Reports Server (NTRS)
Berkery, E. A.; Krausz, A.
1974-01-01
The first phase of the Multi-kw dc Power Distribution Technology Program is reported and involves the test and evaluation of a technology breadboard in a specifically designed test facility according to design concepts developed in a previous study on space vehicle electrical power processing, distribution, and control. The static and dynamic performance, fault isolation, reliability, electromagnetic interference characterisitics, and operability factors of high distribution systems were studied in order to gain a technology base for the use of high voltage dc systems in future aerospace vehicles. Detailed technical descriptions are presented and include data for the following: (1) dynamic interactions due to operation of solid state and electromechanical switchgear; (2) multiplexed and computer controlled supervision and checkout methods; (3) pulse width modulator design; and (4) cable design factors.
NASA Astrophysics Data System (ADS)
Nolan, S.; Jones, C. E.; Munro, R.; Norman, P.; Galloway, S.; Venturumilli, S.; Sheng, J.; Yuan, W.
2017-12-01
Hybrid electric propulsion aircraft are proposed to improve overall aircraft efficiency, enabling future rising demands for air travel to be met. The development of appropriate electrical power systems to provide thrust for the aircraft is a significant challenge due to the much higher required power generation capacity levels and complexity of the aero-electrical power systems (AEPS). The efficiency and weight of the AEPS is critical to ensure that the benefits of hybrid propulsion are not mitigated by the electrical power train. Hence it is proposed that for larger aircraft (~200 passengers) superconducting power systems are used to meet target power densities. Central to the design of the hybrid propulsion AEPS is a robust and reliable electrical protection and fault management system. It is known from previous studies that the choice of protection system may have a significant impact on the overall efficiency of the AEPS. Hence an informed design process which considers the key trades between choice of cable and protection requirements is needed. To date the fault response of a voltage source converter interfaced DC link rail to rail fault in a superconducting power system has only been investigated using simulation models validated by theoretical values from the literature. This paper will present the experimentally obtained fault response for a variety of different types of superconducting tape for a rail to rail DC fault. The paper will then use these as a platform to identify key trades between protection requirements and cable design, providing guidelines to enable future informed decisions to optimise hybrid propulsion electrical power system and protection design.
Secured independent tools in peritoneoscopy.
Tsin, Daniel A; Davila, Fausto; Dominguez, Guillermo; Manolas, Panagiotis
2010-01-01
Secured independent tools are being introduced to aid in peritoneoscopy. We present a simple technique for anchoring instruments, powered lights, and micro machines through the abdominal wall. We used a laparoscopic trainer, micro alligator clips with one or two 2-0 nylon tails and cables for engines and lights. The above instruments were introduced via a 12-mm or 15-mm port. Clips were placed for traction, retraction and exposure, lights for illumination, and motors for potential work. A laparoscopy port closure or suture passer was introduced percutaneously to grab and extract the tails or cables outside of the simulated abdominal cavity. The engines and lights were powered by a direct electric current (DC) plugged into exteriorized cables. We used 2 to 3 clips for each, and engines performed well. This basic simulation adds independent instruments, lights, and engines. We replaced cannulas with threads or cables in an attempt to limit the number of ports. This technique further opens the door for innovations in wired machines in laparoscopy, single-port laparoscopy, or natural orifice surgery.
Modeling AC ripple currents in HTS coated conductors by integral equations
NASA Astrophysics Data System (ADS)
Grilli, Francesco; Xu, Zhihan
2016-12-01
In several HTS applications, the superconducting tapes experience the simultaneous presence of DC and AC excitations. For example in high-current DC cables, where the transport current is not perfectly constant, but it exhibits some ripples at different frequencies introduced by the rectification process (AC-DC conversion). These ripples give rise to dissipation, whose magnitude and possible influence on the device's cooling requirements need to be evaluated. Here we report a study of the AC losses in a HTS coated conductor subjected to DC currents and AC ripples simultaneously. The modeling approach is based on an integral equation method for thin superconductors: the superconducting tape is modeled as a 1-D object with a non-linear resistivity, which includes the dependence of the critical current density Jc on the magnetic field. The model, implemented in a commercial finite-element program, runs very fast (the simulation of one AC cycle typically takes a few seconds on standard desktop workstation): this allows simulating a large number of cycles and estimating when the AC ripple losses stabilize to a constant value. The model is used to study the influence of the flux creep power index n on the stabilization speed and on the AC loss values, as well as the effect of using a field-dependent Jc instead of a constant one. The simulations confirm that the dissipation level should not be a practical concern in HTS DC cables. At the same time, however, they reveal a strong dependence of the results upon the power index n and the form of Jc , which spurs the question whether the power-law is the most suitable description of the superconductor's electrical behavior for this kind of analysis.
Simulation and control of a 20 kHz spacecraft power system
NASA Technical Reports Server (NTRS)
Wasynczuk, O.; Krause, P. C.
1988-01-01
A detailed computer representation of four Mapham inverters connected in a series, parallel arrangement has been implemented. System performance is illustrated by computer traces for the four Mapham inverters connected to a Litz cable with parallel resistance and dc receiver loads at the receiving end of the transmission cable. Methods of voltage control and load sharing between the inverters are demonstrated. Also, the detailed computer representation is used to design and to demonstrate the advantages of a feed-forward voltage control strategy. It is illustrated that with a computer simulation of this type, the performance and control of spacecraft power systems may be investigated with relative ease and facility.
The protection of photovoltaic power systems from lightning
NASA Astrophysics Data System (ADS)
Rogers, C. B.
Lightning protection techniques at nine prototype photovoltaic power system sites with outputs from 18-225 kW are described. Noting that protection schemes are devised to fit isokeraunic data for specific sites, grounding is cited as a common feature for all systems. The grounds are, in separate instances, connected to junction boxes, frames of the solar cell panels, lead from the dc center, from the dc negative terminal, from the frames and equipment, at the array turntable, or from the building rebar frames. The dc power cables are protected by either metal conduit, metal conduit ground wire, direct burial, by rigid metal conduit, ground conductors, or by ground conductors at the ends of the conduit run. Costs run from 0.01-0.28$/W, with all the systems outfitted with bypass and blocking diodes. Direct stroke protection is viewed as less important than isokeraunic data.
The MSPICE simulation of a saturating transformer
NASA Astrophysics Data System (ADS)
Maclean, David N.
A transformer is simulated using a nonlinear saturating magnetic model. Hysteresis and gradual smooth reduction of core permeability are achieved with standard SPICE networks and functions. The equations that define the nonlinear inductance and the MSPICE circuits used to simulate them are derived. A hierarchy of circuit complexity that is based on the structured logic design subcircuit method is used. An example of a push-pull buck regulator being operated in an unbalanced condition is given. Noise ripple on the input power cable generates a dc offset current in the transformer. The example demonstrates how avionics power equipment can be evaluated for large-signal ac, dc, and transient behavior.
Performance evolution of 60 kA HTS cable prototypes in the EDIPO test facility
NASA Astrophysics Data System (ADS)
Bykovsky, N.; Uglietti, D.; Sedlak, K.; Stepanov, B.; Wesche, R.; Bruzzone, P.
2016-08-01
During the first test campaign of the 60 kA HTS cable prototypes in the EDIPO test facility, the feasibility of a novel HTS fusion cable concept proposed at the EPFL Swiss Plasma Center (SPC) was successfully demonstrated. While the measured DC performance of the prototypes at magnetic fields from 8 T to 12 T and for currents from 30 kA to 70 kA was close to the expected one, an initial electromagnetic cycling test (1000 cycles) revealed progressive degradation of the performance in both the SuperPower and SuperOx conductors. Aiming to understand the reasons for the degradation, additional cycling (1000 cycles) and warm up-cool down tests were performed during the second test campaign. I c performance degradation of the SuperOx conductor reached ∼20% after about 2000 cycles, which was reason to continue with a visual inspection of the conductor and further tests at 77 K. AC tests were carried out at 0 and 2 T background fields without transport current and at 10 T/50 kA operating conditions. Results obtained in DC and AC tests of the second test campaign are presented and compared with appropriate data published recently. Concluding the first iteration of the HTS cable development program at SPC, a summary and recommendations for the next activity within the HTS fusion cable project are also reported.
Optically Controlled Devices and Ultrafast Laser Sources for Signal Processing.
1987-06-30
A2 are input/output cavity coupling elements. C1 and C2 are coaxial cables. The resistance (R) and inductance L) provide isolation between the DC power ...the same power . 3. The continuously operating phosphate Nd:glass laser has been modelocked for the first time ever to generate 7 ps pulses. We have...media in a modelocked laser to understand the fundamental pulse generation mechanism. 2. Develop compact, high- power sources of short pulses using
A drive unit for the instrument pointing system
NASA Technical Reports Server (NTRS)
Birner, R.; Roth, M.
1981-01-01
The requirements, capabilities, and unique design features of the instrument pointing system drive units (DU) are presented. The DU's are identical for all three gimbal axes (elevation, cross elevation, and azimuth) and provide alternating rotation of shaft versus the housing of + or - 180 deg. The design features include: two ball bearing cartridges using cemented carbide balls coated with TiC a layer; redundant brushless torque motors and resolvers; a load by-pass mechanism driven by a dc torque motor to off-load the bearings during ascent/descent, ground transportation, and to provide an emergency breaking capability; and cabling over each gimbal axis by means of cable follow-up consisting of 13 signal and 15 power flat band cable loops. Test results of disturbance torque characteristics are presented.
Inverter communications using output signal
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chapman, Patrick L.
Technologies for communicating information from an inverter configured for the conversion of direct current (DC) power generated from an alternative source to alternating current (AC) power are disclosed. The technologies include determining information to be transmitted from the inverter over a power line cable connected to the inverter and controlling the operation of an output converter of the inverter as a function of the information to be transmitted to cause the output converter to generate an output waveform having the information modulated thereon.
DOE Office of Scientific and Technical Information (OSTI.GOV)
None
2012-01-09
GENI Project: General Atomics is developing a direct current (DC) circuit breaker that could protect the grid from faults 100 times faster than its alternating current (AC) counterparts. Circuit breakers are critical elements in any electrical system. At the grid level, their main function is to isolate parts of the grid where a fault has occurred—such as a downed power line or a transformer explosion—from the rest of the system. DC circuit breakers must interrupt the system during a fault much faster than AC circuit breakers to prevent possible damage to cables, converters and other grid-level components. General Atomics’ high-voltagemore » DC circuit breaker would react in less than 1/1,000th of a second to interrupt current during a fault, preventing potential hazards to people and equipment.« less
A Hybrid LCC-VSC HVDC Transmission System Supplying a Passive Load
NASA Astrophysics Data System (ADS)
Kotb, Omar
High Voltage Direct Current (HVDC) transmission systems continue to be an excellent asset in modern power systems, mainly for their ability to overcome the problems of AC transmission, such as the interconnection of asynchronous grids, stability of long transmission lines, and use of long cables for power transmission. In the past 20 years, Voltage Source Converter (VSC)-HVDC transmission systems were developed and installed in many projects, thereby adding more operational benefits to DC transmission option, such as high controllability, ability to supply weak networks, and reduced converter reactive power demand. Nevertheless, VSC-HVDC transmission suffers from the disadvantages of high losses and cost. In this research, a hybrid HVDC employing a Line Commutated Converter (LCC) as rectifier and a VSC as inverter is used to supply a passive network through a DC cable. The hybrid system is best suited for unidirectional power transmission scenarios, such as power transmission to islands and remote load centers, where the construction of new transmission lines is prohibitively expensive. Control modes for the rectifier and inverter are selected and implemented using Proportional Integral (PI) controllers. Special control schemes are developed for abnormal operating conditions such as starting at light load and recovering from AC network faults. The system performance under steady state and transient conditions is investigated by EMTP-RV simulations. The results show the feasibility of the hybrid system.
NASA Astrophysics Data System (ADS)
Lee, S.; Petrykin, V.; Molodyk, A.; Samoilenkov, S.; Kaul, A.; Vavilov, A.; Vysotsky, V.; Fetisov, S.
2014-04-01
The SuperOx and SuperOx Japan LLC companies were founded with the goal of developing a cost-effective technology for second generation HTS (2G HTS) tapes by utilizing a combination of the most advanced chemical and physical deposition techniques, together with implementing original tape architectures. In this paper we present a brief overview of our production and experimental facilities and recent results of 2G HTS tape fabrication, and describe the first tests of the tapes in model cables for AC and DC power application.
Effects of EMF emissions from undersea electric cables on coral reef fish.
Kilfoyle, Audie K; Jermain, Robert F; Dhanak, Manhar R; Huston, Joseph P; Spieler, Richard E
2018-01-01
The objective of this study was to determine if electromagnetic field (EMF) emissions from undersea power cables impacted local marine life, with an emphasis on coral reef fish. The work was done at the South Florida Ocean Measurement Facility of Naval Surface Warfare Center in Broward County, Florida, which has a range of active undersea detection and data transmission cables. EMF emissions from a selected cable were created during non-destructive visual fish surveys on SCUBA. During surveys, the transmission of either alternating current (AC), direct current (DC), or none (OFF) was randomly initiated by the facility at a specified time. Visual surveys were conducted using standardized transect and point-count methods to acquire reef fish abundances and species richness prior to and immediately after a change in transmission frequency. The divers were also tasked to note the reaction of the reef fish to the immediate change in EMF during a power transition. In general, analysis of the data did not find statistical differences among power states and any variables. However, this may be a Type II error as there are strong indications of a potential difference of a higher abundance of reef fish at the sites when the power was off, and further study is warranted. Bioelectromagnetics. 39:35-52, 2018. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.
NASA Technical Reports Server (NTRS)
Hammel, R. L. (Editor); Smith, A. G. (Editor)
1974-01-01
The design and application of a supplementary power and heat rejection kit for the Spacelab are discussed. Two subsystems of electric power and thermal control were analyzed to define the requirements for the power and heat rejection kit (PHRK). Twelve exemplary experiments were defined and power timelines were developed. From these timeline, the experiment requirements for sustained power, peak power, and energy were determined. The electrical power subsystem of the PHRK will consist of two fuel cells, oxygen and hydrogen reactant tank assemblies, water storage tanks, plumbing, cabling, and inverters to convert the nominal 28 volt dc fuel cell output to ac power.
NASA Astrophysics Data System (ADS)
Cardwell, D. A.; Amemiya, N.; Fair, R.
2012-01-01
This focus section of Superconductor Science and Technology looks at the properties, technology and applications of (RE)BCO and MgB2 based superconductors for power engineering systems. Both bulk and conductor forms of material are addressed, including elements of materials fabrication and processing, and the measurement of their applied properties for various levels of system application. The areas of research include ac losses in type II materials in power devices, cables and coated conductors, the development of high current dc cables and the application of superconductors in levitation devices, motors and fault current limiters. This focus section presents a broad cross-section of contemporary issues, that represent state-of-the-art for power applications of superconductors, and highlights the areas that require further development if commercial applications of these rapidly emerging materials are to be realised. It contains papers from some of the major groups in the field, including contributions from Europe, the USA and Japan, and describes devices that are relatively close to market.
NASA Ames Research Center 60 MW Power Supply Modernization
NASA Technical Reports Server (NTRS)
Choy, Yuen Ching; Ilinets, Boris V.; Miller, Ted; Nagel, Kirsten (Technical Monitor)
2001-01-01
The NASA Ames Research Center 60 MW DC Power Supply was built in 1974 to provide controlled DC power for the Thermophysics Facility Arc Jet Laboratory. The Power Supply has gradually losing reliability due to outdated technology and component life limitation. NASA has decided to upgrade the existing rectifier modules with contemporary high-power electronics and control equipment. NASA plans to complete this project in 2001. This project includes a complete replacement of obsolete thyristor stacks in all six rectifier modules and rectifier bridge control system. High power water-cooled thyristors and freewheeling diodes will be used. The rating of each of the six modules will be 4000 A at 5500 V. The control firing angle signal will be sent from the Facility Control System to six modules via fiberoptic cable. The Power Supply control and monitoring system will include a Master PLC in the Facility building and a Slave PLC in each rectifier module. This system will also monitor each thyristor level in each stack and the auxiliary equipment.
Kavet, Robert; Wyman, Megan T.; Klimley, A. Peter; ...
2016-02-25
Here, the Trans Bay Cable (TBC) is a ±200-kilovolt (kV), 400 MW 85-km long High Voltage Direct Current (DC) buried transmission line linking Pittsburg, CA with San Francisco, CA (SF) beneath the San Francisco Estuary. The TBC runs parallel to the migratory route of various marine species, including green sturgeon, Chinook salmon, and steelhead trout. In July and August 2014, an extensive series of magnetic field measurements were taken using a pair of submerged Geometrics magnetometers towed behind a survey vessel in four locations in the San Francisco estuary along profiles that cross the cable’s path; these included the Sanmore » Francisco-Oakland Bay Bridge (BB), the Richmond-San Rafael Bridge (RSR), the Benicia- Martinez Bridge (Ben) and an area in San Pablo Bay (SP) in which a bridge is not present. In this paper, we apply basic formulas that ideally describe the magnetic field from a DC cable summed vectorially with the background geomagnetic field (in the absence of other sources that would perturb the ambient field) to derive characteristics of the cable that are otherwise not immediately observable. Magnetic field profiles from measurements taken along 170 survey lines were inspected visually for evidence of a distinct pattern representing the presence of the cable. Many profiles were dominated by field distortions unrelated to the cable caused by bridge structures or other submerged objects, and the cable’s contribution to the field was not detectable. BB, with 40 of the survey lines, did not yield usable data for these reasons. The unrelated anomalies could be up to 100 times greater than those from the cable. In total, discernible magnetic field profiles measured from 76 survey lines were regressed against the equations, representing eight days of measurement. The modeled field anomalies due to the cable (the difference between the maximum and minimum field along the survey line at the cable crossing) were virtually identical to the measured values. The modeling yielded a pooled cable depth below the bay floor of 2.06 m (±1.46 std dev), and estimated the angle to the horizontal of the imaginary line connecting the crosssectional center of the cable’s two conductors (0.1143 m apart) as 178.9° ±61.9° (std dev) for Ben, 78.6°±37.0° (std dev) for RSR, and 139.9°±27.4° (std dev) for SP. The mean of the eight daily average currents derived from the regressions was 986 ±185 amperes (A) (std dev), as compared to 722 ±95 A (std dev) provided by Trans Bay Cable LLC. Overall, the regressions based on fundamental principles (Biot Savart law) and the vectorial summation of cable and geomagnetic fields provide estimates of cable characteristics consistent with plausible expectations.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kavet, Robert; Wyman, Megan T.; Klimley, A. Peter
Here, the Trans Bay Cable (TBC) is a ±200-kilovolt (kV), 400 MW 85-km long High Voltage Direct Current (DC) buried transmission line linking Pittsburg, CA with San Francisco, CA (SF) beneath the San Francisco Estuary. The TBC runs parallel to the migratory route of various marine species, including green sturgeon, Chinook salmon, and steelhead trout. In July and August 2014, an extensive series of magnetic field measurements were taken using a pair of submerged Geometrics magnetometers towed behind a survey vessel in four locations in the San Francisco estuary along profiles that cross the cable’s path; these included the Sanmore » Francisco-Oakland Bay Bridge (BB), the Richmond-San Rafael Bridge (RSR), the Benicia- Martinez Bridge (Ben) and an area in San Pablo Bay (SP) in which a bridge is not present. In this paper, we apply basic formulas that ideally describe the magnetic field from a DC cable summed vectorially with the background geomagnetic field (in the absence of other sources that would perturb the ambient field) to derive characteristics of the cable that are otherwise not immediately observable. Magnetic field profiles from measurements taken along 170 survey lines were inspected visually for evidence of a distinct pattern representing the presence of the cable. Many profiles were dominated by field distortions unrelated to the cable caused by bridge structures or other submerged objects, and the cable’s contribution to the field was not detectable. BB, with 40 of the survey lines, did not yield usable data for these reasons. The unrelated anomalies could be up to 100 times greater than those from the cable. In total, discernible magnetic field profiles measured from 76 survey lines were regressed against the equations, representing eight days of measurement. The modeled field anomalies due to the cable (the difference between the maximum and minimum field along the survey line at the cable crossing) were virtually identical to the measured values. The modeling yielded a pooled cable depth below the bay floor of 2.06 m (±1.46 std dev), and estimated the angle to the horizontal of the imaginary line connecting the crosssectional center of the cable’s two conductors (0.1143 m apart) as 178.9° ±61.9° (std dev) for Ben, 78.6°±37.0° (std dev) for RSR, and 139.9°±27.4° (std dev) for SP. The mean of the eight daily average currents derived from the regressions was 986 ±185 amperes (A) (std dev), as compared to 722 ±95 A (std dev) provided by Trans Bay Cable LLC. Overall, the regressions based on fundamental principles (Biot Savart law) and the vectorial summation of cable and geomagnetic fields provide estimates of cable characteristics consistent with plausible expectations.« less
Testing of a 1.25-m HTS Cable Made from YBCO Tapes
NASA Astrophysics Data System (ADS)
Gouge, M. J.; Lue, J. W.; Demko, J. A.; Duckworth, R. C.; Fisher, P. W.; Daumling, M.; Lindsay, D. T.; Roden, M. L.; Tolbert, J. C.
2004-06-01
Ultera and Oak Ridge National Laboratory (ORNL) have jointly designed, built, and tested a 1.25-m-long, prototype high-temperature superconducting (HTS) power cable made from 1-cm-wide, second-generation YBa2Cu3Ox (YBCO)-coated conductor tapes. Electrical tests of this cable were performed in boiling liquid nitrogen at 77 K. DC testing of the 1.25-m cable included determination of the V-I curve, with a critical current of 4200 A. This was consistent with the properties of the 24 individual YBCO tapes. AC testing of the cable was conducted at currents up to 2500 Arms. The ac losses were measured calorimetrically by measuring the response of a calibrated temperature sensor placed on the former and electrically by use of a Rogowski coil with a lock-in amplifier. AC losses of about 2 W/m were measured at a cable ac current of 2000 Arms. Overcurrent testing was conducted at peak current values up to 12 kA for pulse lengths of 0.1-0.2 s. The cable temperature increased to 105 K for a 12 kA, 0.2 s overcurrent pulse, and the cable showed no degradation after the sequence of overcurrent testing. This commercial-grade HTS cable demonstrated the feasibility of second-generation YBCO tapes in an ac cable application.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Klimley, A. P.; Wyman, M. T.; Kavet, Rob
The US Department of Energy and US Department of the Interior, Bureau of Ocean Energy Management commissioned this study to address the limited scientific data on the impacts of high voltage direct current cables on aquatic biota, in particular migratory species within the San Francisco Bay. Empirical evidence exists that marine animals perceive and orient to local distortions in the earth’s main geomagnetic field magnetic field. The electromagnetic fields (EMF) generated by the cables that carry electricity from hydrokinetic energy sources to shore-based power stations may produce similar local distortions in the earth’s main field. Concern exists that animals thatmore » migrate along the continental shelves might orient to the EMF from the cables, and move either inshore or offshore away from their normal path. The Trans Bay Cable (TBC) is a ±200-kilovolt (kV), 400 MW 85-km long High Voltage Direct Current (DC) buried transmission line linking Pittsburg, CA with San Francisco, CA (SF) through the San Francisco Bay. The study addresses the following specific questions based on measurements and projections of the EMF produced by an existing marine cable, the TBC, in San Francisco Bay. Specifically, does the presence of EMF from an operating power cable alter the behavior and path of bony fishes and sharks along a migratory corridor? Does the EMF from an operating power cable guide migratory movements or pose an obstacle to movement? To meet the main study objectives several activities needed to be carried out: 1) modeling of the magnetic fields produced by the TBC, 2) assessing the migratory impacts on Chinook salmon smolts (Oncorhynchus tshawytscha) and green sturgeon (Acipenser medirostris) as a result of local magnetic field distortions produced by bridge structures and 3) analyzing behavioral responses by migratory Chinook salmon and green sturgeon to a high-voltage power cable. To meet the first objective, magnetic field measurements were made using two submerged Geometrics magnetometers towed behind a survey vessel in four locations in the San Francisco estuary along profiles crossing the cable path. We applied basic formulas to describe magnetic field from a DC cable summed vectorially with the background geomagnetic field (in the absence of other sources that would perturb the ambient field) to derive characteristics of the cable not immediately or otherwise observable. The magnetic field profiles of 76 survey lines were regressed against the measured fields, representing eight days of measurement. Many profiles were dominated by field distortions caused by bridge structures or other submerged objects, and the cable contribution to the field was not detectable. The regressions based on fundamental principles (Biot Savart law) and the vectorial summation of cable and geomagnetic fields provide estimates of cable characteristics consistent with plausible expectations. For the second objective, detailed gradiometer survey were examined. Distortions in the earth’s main field produced by bridges across the estuary were much greater than those from the TBC. The former anomalies exceeded the latter by an order of magnitude or more. Significant numbers of tagged Chinook salmon smolts migrated past bridges, which produced strong magnetic anomalies, to the Golden Gate Bridge, where they were recorded by dual arrays of acoustic tag-detecting monitors moored in lines across the mouth of the bay. Adult green sturgeon successfully swam upstream and downstream through the estuary on the way to and from their spawning grounds. Hence, the large anomalies produced by the bridges that run perpendicular to these migration routes do not appear to present a strong barrier to the natural seasonal movement patterns of salmonid smolts and adult green sturgeon. Finally, to assess the behavioral responses by migratory Chinook salmon and green sturgeon to a high- voltage power cable - the potential impacts effect of the TBC on fishes migrating through the San Francisco Estuary were examined. These included late-fall run Chinook salmon smolts (Oncorhynchus tshawytscha) that migrate downstream through the San Francisco Estuary to the Pacific Ocean and adult green sturgeon (Acipenser medirostris), which migrate upstream from the ocean through the estuary to their spawning habitat in the upper Sacramento River and return to the ocean after spawning occurs. Our results indicate Chinook salmon smolts may be attracted to the cable after activation (more cable location crossings, more detections at Bay Bridge, high importance of distance to cable in predicting fish location), but are not impeded from successfully migrating through the San Francisco Bay (similar proportions of successful exits, faster transit rates). Cable activity had opposite effects on outbound and inbound green sturgeon migrations: outbound migrations had significantly longer transit times while inbound migrations had significantly shorter migration times. However, the proportion of green sturgeon that successfully migrated through the San Francisco Bay was not strongly impacted after cable activation for either migration type. Based on the work, we provide the following conclusions: 1) calculations of magnetic fields for assessment of marine life can be performed; however, local anomalies in the fields resulting from submerged structures require validation of such calculations through collection of ambient DC magnetic field data, 2) the large anomalies produced by the bridges that run perpendicular to these migration routes do not appear to present a strong barrier to the natural seasonal movement patterns of salmonid smolts and adult green sturgeon and 3) Chinook salmon smolts may be attracted to the activated cable based on analysis of cable crossing, misdirections, and first presence at the array data, however, the cable activation does not appear to change the proportion of smolts that successfully migrate through the San Francisco Bay. Cable activation impacts inbound and outbound migrating adult green sturgeon: travel time was increased for outbound migrations but decreased for inbound migrations. However, cable activation did not appear to impact the success of either migration type in this species.« less
Design and characterization of a powered elbow prosthesis.
Bennett, Daniel A; Mitchell, Jason; Goldfarb, Michael
2015-01-01
This paper describes the design of a powered elbow prosthesis, which incorporates a belt and cable drive transmission with a brushless DC motor to achieve an output torque of approximately 18.4 Nm, a backdrive torque of 1.5 Nm, and a speed of up to 360 deg/s while remaining within the anthropomorphic envelope with regard to mass and size. The measured torque and speed of the prosthesis is commensurate with nominal capability of the natural limb (for purposes of performing activities of daily living).
Lightning vulnerability of fiber-optic cables.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Martinez, Leonard E.; Caldwell, Michele
2008-06-01
One reason to use optical fibers to transmit data is for isolation from unintended electrical energy. Using fiber optics in an application where the fiber cable/system penetrates the aperture of a grounded enclosure serves two purposes: first, it allows for control signals to be transmitted where they are required, and second, the insulating properties of the fiber system help to electrically isolate the fiber terminations on the inside of the grounded enclosure. A fundamental question is whether fiber optic cables can allow electrical energy to pass through a grounded enclosure, with a lightning strike representing an extreme but very importantmore » case. A DC test bed capable of producing voltages up to 200 kV was used to characterize electrical properties of a variety of fiber optic cable samples. Leakage current in the samples were measured with a micro-Ammeter. In addition to the leakage current measurements, samples were also tested to DC voltage breakdown. After the fiber optic cables samples were tested with DC methods, they were tested under representative lightning conditions at the Sandia Lightning Simulator (SLS). Simulated lightning currents of 30 kA and 200 kA were selected for this test series. This paper documents measurement methods and test results for DC high voltage and simulated lightning tests performed at the Sandia Lightning Simulator on fiber optic cables. The tests performed at the SLS evaluated whether electrical energy can be conducted inside or along the surface of a fiber optic cable into a grounded enclosure under representative lightning conditions.« less
The LSLE echocardiograph - Commercial hardware aboard Spacelab. [Life Sciences Laboratory Equipment
NASA Technical Reports Server (NTRS)
Schwarz, R.
1983-01-01
The Life Sciences Laboratory Equipment Echocardiograph, a commercial 77020AC Ultrasound Imaging System modified to meet NASA's spacecraft standards, is described. The assembly consists of four models: display and control, scanner, scan converter, and physioamplifiers. Four separate processors communicate over an IEE-488 bus, and the system has more than 6000 individual components on 35 printed circuit cards. Three levels of self test are provided: a short test during power up, a basic test initiated by a front panel switch, and interactive tests for specific routines. Default mode operation further enhances reliability. Modifications of the original system include the replacement of ac power supplies with dc to dc converters, a slide-out keyboard (to prevent accidental operation), Teflon insulated wire, and additional shielding for the ultrasound transducer cable.
McClellan PV system installation provides key lessons
NASA Astrophysics Data System (ADS)
Kauffman, W. R.
Design features and lessons learned in the installation of a 40 kWp solar cell array to supply power to a market on an airbase are outlined. The fixed-position modules interface with an inverter, ac and dc switchgear, controls, instrumentation, and an energy management system. The power control unit has a peak power tracking feature to maximize output from the 1142 cell modules. The inverter has functioned at over 98 percent efficiency near the 25 kW design range of the array. Moisture sealing to prevent ground faults was found necessary during the installation of the underground cabling.
Artificial neural network application for space station power system fault diagnosis
NASA Technical Reports Server (NTRS)
Momoh, James A.; Oliver, Walter E.; Dias, Lakshman G.
1995-01-01
This study presents a methodology for fault diagnosis using a Two-Stage Artificial Neural Network Clustering Algorithm. Previously, SPICE models of a 5-bus DC power distribution system with assumed constant output power during contingencies from the DDCU were used to evaluate the ANN's fault diagnosis capabilities. This on-going study uses EMTP models of the components (distribution lines, SPDU, TPDU, loads) and power sources (DDCU) of Space Station Alpha's electrical Power Distribution System as a basis for the ANN fault diagnostic tool. The results from the two studies are contrasted. In the event of a major fault, ground controllers need the ability to identify the type of fault, isolate the fault to the orbital replaceable unit level and provide the necessary information for the power management expert system to optimally determine a degraded-mode load schedule. To accomplish these goals, the electrical power distribution system's architecture can be subdivided into three major classes: DC-DC converter to loads, DC Switching Unit (DCSU) to Main bus Switching Unit (MBSU), and Power Sources to DCSU. Each class which has its own electrical characteristics and operations, requires a unique fault analysis philosophy. This study identifies these philosophies as Riddles 1, 2 and 3 respectively. The results of the on-going study addresses Riddle-1. It is concluded in this study that the combination of the EMTP models of the DDCU, distribution cables and electrical loads yields a more accurate model of the behavior and in addition yielded more accurate fault diagnosis using ANN versus the results obtained with the SPICE models.
EVA Metro Sedan electric-propulsion system: test and evaluation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Reimers, E.
1979-09-01
The procedure and results of the performance evaluation of the EVA Metro Sedan (car No. 1) variable speed dc chopper motor drive and its three speed automatic transmission are presented. The propulsion system for a battery powered vehicle manufactured by Electric Vehicle Associates, Valley View, Ohio, was removed from the vehicle, mounted on the programmable electric dynamometer test facility and evaluated with the aid of a hp 3052A Data Acquisition System. Performance data for the automatic transmission, the solid state dc motor speed controller, and the dc motor in the continuous and pulsating dc power mode, as derived on themore » dynamometer test facility, as well as the entire propulsion system are given. This concept and the system's components were evaluated in terms of commercial applicability, maintainability, and energy utility to establish a design base for the further development of this system or similar propulsion drives. The propulsion system of the EVA Metro Sedan is powered by sixteen 6-volt traction batteries, Type EV 106 (Exide Battery Mfg. Co.). A thyristor controlled cable form Pulsomatic Mark 10 controller, actuated by a foot throttle, controls the voltage applied to a dc series field motor, rated at 10 hp at 3800 rpm (Baldor Electric Co.). Gear speed reduction to the wheel is accomplished by the original equipment three speed automatic transmission with torque converter (Renault 12 Sedan). The brake consists of a power-assisted, hydraulic braking system with front wheel disk and rear drum. An ability to recuperate electric energy with subsequent storage in the battery power supply is not provided.« less
Federal Register 2010, 2011, 2012, 2013, 2014
2010-08-06
... facilities authorized by Presidential Permit No. PP-22, as amended, include seven single conductor 132 kilovolt (kV) submarine cables and three single conductor 260 kV DC submarine cables. These cables do not...
NASA Technical Reports Server (NTRS)
Wasynczuk, O.; Krause, P. C.; Biess, J. J.; Kapustka, R.
1990-01-01
A detailed computer simulation was used to illustrate the steady-state and dynamic operating characteristics of a 20-kHz resonant spacecraft power system. The simulated system consists of a parallel-connected set of DC-inductor resonant inverters (drivers), a 440-V cable, a node transformer, a 220-V cable, and a transformer-rectifier-filter (TRF) AC-to-DC receiver load. Also included in the system are a 1-kW 0.8-pf RL load and a double-LC filter connected at the receiving end of the 20-kHz AC system. The detailed computer simulation was used to illustrate the normal steady-state operating characteristics and the dynamic system performance following, for example, TRF startup. It is shown that without any filtering the given system exhibits harmonic resonances due to an interaction between the switching of the source and/or load converters and the AC system. However, the double-LC filter at the receiving-end of the AC system and harmonic traps connected in series with each of the drivers significantly reduce the harmonic distortion of the 20-kHz bus voltage. Significant additional improvement in the waveform quality can be achieved by including a double-LC filter with each driver.
Centralized vs decentralized lunar power system study
NASA Astrophysics Data System (ADS)
Metcalf, Kenneth; Harty, Richard B.; Perronne, Gerald E.
1991-09-01
Three power-system options are considered with respect to utilization on a lunar base: the fully centralized option, the fully decentralized option, and a hybrid comprising features of the first two options. Power source, power conditioning, and power transmission are considered separately, and each architecture option is examined with ac and dc distribution, high and low voltage transmission, and buried and suspended cables. Assessments are made on the basis of mass, technological complexity, cost, reliability, and installation complexity, however, a preferred power-system architecture is not proposed. Preferred options include transmission based on ac, transmission voltages of 2000-7000 V with buried high-voltage lines and suspended low-voltage lines. Assessments of the total cost associated with the installations are required to determine the most suitable power system.
Portable Fan Assembly for the International Space Station
NASA Technical Reports Server (NTRS)
Jenkins, Arthur A.; Roman, Monsi C.
1999-01-01
NASA/ Marshall Space Flight Center (NASA/MSFC) is responsible for the design and fabrication of a Portable Fan Assembly (PFA) for the International Space Station (ISS). The PFA will be used to enhance ventilation inside the ISS modules as needed for crew comfort and for rack rotation. The PFA consists of the fan on-orbit replaceable unit (ORU) and two noise suppression packages (silencers). The fan ORU will have a mechanical interface with the Seat Track Equipment Anchor Assembly, in addition to the power supply module which includes a DC-DC converter, on/standby switch, speed control, power cable and connector. This paper provides a brief development history, including the criteria used for the fan, and a detailed description of the PFA operational configurations. Space Station requirements as well as fan performance characteristics are also discussed.
Determination of ac conductor and pipe loss in pipe-type cable systems. Final report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Silver, D.A.; Seman, G.W.
1982-02-01
The results are presented of investigations into the determination of the ac/dc resistance ratios of high and extra high voltage pipe-type cables with conventional and large size segmental conductors in carbon steel, stainless steel and aluminum pipes in three cable per pipe and single cable per pipe configurations. The measurements included 115 through 765 kV cables with copper, enamel coated copper, and aluminum conductors in sizes of 2000 kcmil (1015 mm/sup 2/), 3250 kcmil (1650 mm/sup 2/), and 3500 kcmil (1776 mm/sup 2/). Calculations using presently available techniques were employed to provide correlation between measured and calculated values in bothmore » magnetic and non-magnetic pipes. In addition, a number of new techniques in conductor construction, pipe material and pipe liners and cable wraps were investigated as means of decreasing the ac/dc resistance ratios of pipe-type cables. Finally, the various systems studied were compared on the basis of system MVA rating and by evaluation of installed and overall operating costs as compared to conventional three cable per pipe systems installed in carbon steel pipes.« less
30 CFR 77.605 - Breaking trailing cable and power cable connections.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Breaking trailing cable and power cable... OF UNDERGROUND COAL MINES Trailing Cables § 77.605 Breaking trailing cable and power cable connections. Trailing cable and power cable connections between cables and to power sources shall not be made...
30 CFR 77.605 - Breaking trailing cable and power cable connections.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Breaking trailing cable and power cable... OF UNDERGROUND COAL MINES Trailing Cables § 77.605 Breaking trailing cable and power cable connections. Trailing cable and power cable connections between cables and to power sources shall not be made...
30 CFR 77.605 - Breaking trailing cable and power cable connections.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Breaking trailing cable and power cable... OF UNDERGROUND COAL MINES Trailing Cables § 77.605 Breaking trailing cable and power cable connections. Trailing cable and power cable connections between cables and to power sources shall not be made...
30 CFR 77.605 - Breaking trailing cable and power cable connections.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Breaking trailing cable and power cable... OF UNDERGROUND COAL MINES Trailing Cables § 77.605 Breaking trailing cable and power cable connections. Trailing cable and power cable connections between cables and to power sources shall not be made...
30 CFR 77.605 - Breaking trailing cable and power cable connections.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Breaking trailing cable and power cable... OF UNDERGROUND COAL MINES Trailing Cables § 77.605 Breaking trailing cable and power cable connections. Trailing cable and power cable connections between cables and to power sources shall not be made...
NASA Astrophysics Data System (ADS)
Tian, Liang
This study investigated the processing-structure-properties relationships in an Al/Ca composites using both experiments and modeling/simulation. A particular focus of the project was understanding how the strength and electrical conductivity of the composite are related to its microstructure in the hope that a conducting material with light weight, high strength, and high electrical conductivity can be developed to produce overhead high-voltage power transmission cables. The current power transmission cables (e.g., Aluminum Conductor Steel Reinforced (ACSR)) have acceptable performance for high-voltage AC transmission, but are less well suited for high-voltage DC transmission due to the poorly conducting core materials that support the cable weight. This Al/Ca composite was produced by powder metallurgy and severe plastic deformation by extrusion and swaging. The fine Ca metal powders have been produced by centrifugal atomization with rotating liquid oil quench bath, and a detailed study about the atomization process and powder characteristics has been conducted. The microstructure of Al/Ca composite was characterized by electron microscopy. Microstructure changes at elevated temperature were characterized by thermal analysis and indirect resistivity tests. The strength and electrical conductivity were measured by tensile tests and four-point probe resistivity tests. Predicting the strength and electrical conductivity of the composite was done by micro-mechanics-based analytical modeling. Microstructure evolution was studied by mesoscale-thermodynamics-based phase field modeling and a preliminary atomistic molecular dynamics simulation. The application prospects of this composite was studied by an economic analysis. This study suggests that the Al/Ca (20 vol. %) composite shows promise for use as overhead power transmission cables. Further studies are needed to measure the corrosion resistance, fatigue properties and energized field performance of this composite.
On the use of doped polyethylene as an insulating material for HVDC cables
DOE Office of Scientific and Technical Information (OSTI.GOV)
Khalil, M.S.
1996-12-31
The merits of HVDC cables with polymeric insulation are well recognized. However, the development of such cables is still hampered due to the problems resulting from the complicated dependence of the electrical conductivity of the polymer on the temperature and the dc electric field and the effects of space charge accumulation in this material. Different methods have been suggested to solve these problems yet none of these methods seem to give a conclusive solution. The present report provides, firstly a critical review of the previous works reported in the literature concerning the development of HVDC cables with polymeric insulation. Differentmore » aspects of those works are examined and discussed. Secondly, an account is given on an investigation using low density polyethylene (LDPE) doped with an inorganic additive as a candidate insulating material for HVDC cables. Preliminary results from measurements of dc breakdown strength and insulation resistivity of both the undoped and the doped materials are presented. It is shown that the incorporation of an inorganic additive into LDPE has improved the performance of the doped material under polarity reversal dc conditions at room temperature. Moreover, the dependency of the insulation resistivity on temperature for the doped material appears to be beneficially modified.« less
NASA Astrophysics Data System (ADS)
Kumar, M. Ajay; Srikanth, N. V.
2015-01-01
The voltage source converter (VSC) based multiterminal high voltage direct current (MTDC) transmission system is an interesting technical option to integrate offshore wind farms with the onshore grid due to its unique performance characteristics and reduced power loss via extruded DC cables. In order to enhance the reliability and stability of the MTDC system, an adaptive neuro fuzzy inference system (ANFIS) based coordinated control design has been addressed in this paper. A four terminal VSC-MTDC system which consists of an offshore wind farm and oil platform is implemented in MATLAB/ SimPowerSystems software. The proposed model is tested under different fault scenarios along with the converter outage and simulation results show that the novel coordinated control design has great dynamic stabilities and also the VSC-MTDC system can supply AC voltage of good quality to offshore loads during the disturbances.
Effects of EMF Emissions from Cables and Junction Boxes on Marine Species
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dhanak, Manhar; Spieler, Richard; Kilfoyle, Kirk
Studies have shown that diverse aquatic species are electrosensitive. Many fishes, and marine mammals, can either detect, navigate by, or are affected by electromagnetic fields (EMF) with various sensitivities, and their behavior may be impacted by unnatural EMF emissions in the water column. Sharks, rays and skates are known to have the highest sensitivity to electric fields. Electric field emissions in the range 0.5–100 micro volt/m appear to attract them, and emissions over 100 micro volt/m to repulse them. A marine hydrokinetic MHK device will have multiple components and associated multiple submarine cables on the seafloor and running through themore » water column and would potentially increase the level of EMF emissions to which the marine species at the site may be exposed to. There are therefore concerns amongst stakeholders that EMF emissions associated with MHK devices and their components may act as barriers to species migration, cause disorientation, change community compositions and ecosystems, and that they may attract sharks, leading to a local increase in the risk of shark attacks. However, field data to validate and model potential relationships between observed responses and the EMF emissions in situ are sparse. A program of experimental field surveys were conducted off the coast of South Florida, USA to characterize the electromagnetic field (EMF) emissions in the water column from a submarine cable, and to monitor for responses of local aquatic species. The field surveys were conducted at the South Florida Ocean Measurement Facility (SFOMF) off Fort Lauderdale, which is a cabled offshore in-water navy range. It consists of multiple active submarine power cables and a number of junction boxes, with the capability to transmit AC/DC power at a range of strength and frequencies. The site includes significant marine life activities and community structure, including highly mobile species, such as sharks, stingrays, mammals and turtles. SFOMF therefore typifies a setting representative of an offshore location where a MHK device may be sited. Background electromagnetic field (EMF) levels and EMF emissions due to submarine cables were measured using a custom E-field sensor and a commercial magnetometer deployed from an autonomous underwater vehicle (AUV) at various fixed altitudes above the seafloor. EMF signatures detected from power cables and junction boxes are contrasted against ambient background levels and other EMF sources. The potential responses of local marine species were observed at selected representative locations using divers on SCUBA, complemented with fixed cameras on the sea bottom and by a set of video cameras mounted on the AUV. The objectives of the study were: 1) to characterize the EMF emission levels associated with submarine cables 2) to monitor potential responses of aquatic animals to the emissions and 3) to develop an associated database of field observations. As control, observations of EMF levels and in situ marine species were conducted with power in the cable turned off. Good quality measurements of EMF emissions were obtained using the mobile AUV platform and the data from the surveys were used to develop contour maps of the EMF levels in the water column above the live cable as well as to provide information about how the field decays away from the cable. The measurements show good agreement with theoretical models of the how EMF levels decay away from the cable in deep and shallow water environment. Electric fields in excess of 200µV/m were measured in the vicinity of the cable during the power on state. Quarterly surveys by SCUBA divers were conducted, using point and transect count methods, over a period of one year at three locations, one at a shallow site where the water depth is approximately 5m, and the other at the Barracuda Reef where the water depth is approximately 10m. The sampling results were analyzed to determine if the presence of an SFOMF generated EMF alters: (1) abundance, species richness, and assemblage structure of coral reef fishes, (2) the behavior of fishes including elasmobranchs, and (3) the distribution of marine turtles and mammals. Diver observations were also used in attempt to discern if there were any noticeable organismal responses during the transitional period between ambient OFF to energized AC or DC power states, and video footage was intended to augment the in-situ visual survey data and aid in interpretation of the results. Comparisons are provided between observation datasets between the three sites and between the point and transect count methods. Presence of several individual elasmobranch species, including sharks and stingrays, were recorded during the surveys. No apparent effect on richness could be discerned between the power on and off states. No apparent sudden animal movements were observed during transitions between power states.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mueller, Steffen; Weigel, Robert; Koelpin, Alexander
2015-07-01
Signal conditioning and transmission for sensor systems and networks within the containment of nuclear power plants (NPPs) still poses a challenge to engineers, particularly in the case of equipment upgrades for existing plants, temporary measurements, decommissioning of plants, but also for new builds. This paper presents an innovative method for efficient and cost-effective instrumentation within high dose rate areas inside the containment. A transmitter-receiver topology is proposed that allows simultaneous, unidirectional point-to-point transmission of multiple sensor signals by superimposing them on existing AC or DC power supply cables using power line communication (PLC) technology. Thereby the need for costly installationmore » of additional cables and containment penetrations is eliminated. Based on commercial off-the-shelf (COTS) electronic parts, a radiation hard transmitter is designed to operate in harsh environment within the containment during full plant operation. Hardware modularity of the transmitter allows application specific tradeoffs between redundancy and channel bandwidth. At receiver side in non-radiated areas, signals are extracted from the power line, demodulated, and provided either in analog or digital output format. Laboratory qualification tests and field test results within a boiling water reactor (BWR) are validating the proof of concept of the proposed system. (authors)« less
30 CFR 75.607 - Breaking trailing cable and power cable connections.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Breaking trailing cable and power cable....607 Breaking trailing cable and power cable connections. [Statutory Provisions] Trailing cable and power cable connections to junction boxes shall not be made or broken under load. ...
30 CFR 75.607 - Breaking trailing cable and power cable connections.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Breaking trailing cable and power cable....607 Breaking trailing cable and power cable connections. [Statutory Provisions] Trailing cable and power cable connections to junction boxes shall not be made or broken under load. ...
30 CFR 75.607 - Breaking trailing cable and power cable connections.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Breaking trailing cable and power cable....607 Breaking trailing cable and power cable connections. [Statutory Provisions] Trailing cable and power cable connections to junction boxes shall not be made or broken under load. ...
30 CFR 75.607 - Breaking trailing cable and power cable connections.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Breaking trailing cable and power cable....607 Breaking trailing cable and power cable connections. [Statutory Provisions] Trailing cable and power cable connections to junction boxes shall not be made or broken under load. ...
Soft-Fault Detection Technologies Developed for Electrical Power Systems
NASA Technical Reports Server (NTRS)
Button, Robert M.
2004-01-01
The NASA Glenn Research Center, partner universities, and defense contractors are working to develop intelligent power management and distribution (PMAD) technologies for future spacecraft and launch vehicles. The goals are to provide higher performance (efficiency, transient response, and stability), higher fault tolerance, and higher reliability through the application of digital control and communication technologies. It is also expected that these technologies will eventually reduce the design, development, manufacturing, and integration costs for large, electrical power systems for space vehicles. The main focus of this research has been to incorporate digital control, communications, and intelligent algorithms into power electronic devices such as direct-current to direct-current (dc-dc) converters and protective switchgear. These technologies, in turn, will enable revolutionary changes in the way electrical power systems are designed, developed, configured, and integrated in aerospace vehicles and satellites. Initial successes in integrating modern, digital controllers have proven that transient response performance can be improved using advanced nonlinear control algorithms. One technology being developed includes the detection of "soft faults," those not typically covered by current systems in use today. Soft faults include arcing faults, corona discharge faults, and undetected leakage currents. Using digital control and advanced signal analysis algorithms, we have shown that it is possible to reliably detect arcing faults in high-voltage dc power distribution systems (see the preceding photograph). Another research effort has shown that low-level leakage faults and cable degradation can be detected by analyzing power system parameters over time. This additional fault detection capability will result in higher reliability for long-lived power systems such as reusable launch vehicles and space exploration missions.
Integration of offshore wind farms through high voltage direct current networks
NASA Astrophysics Data System (ADS)
Livermore, Luke
The integration of offshore wind farms through Multi Terminal DC (MTDC) networks into the GB network was investigated. The ability of Voltage Source Converter (VSC) High Voltage Direct Current (HVDC) to damp Subsynchronous Resonance (SSR) and ride through onshore AC faults was studied. Due to increased levels of wind generation in Scotland, substantial onshore and offshore reinforcements to the GB transmission network are proposed. Possible inland reinforcements include the use of series compensation through fixed capacitors. This potentially can lead to SSR. Offshore reinforcements are proposed by two HVDC links. In addition to its primary functions of bulk power transmission, a HVDC link can be used to provide damping against SSR, and this function has been modelled. Simulation studies have been carried out in PSCAD. In addition, a real-time hardware-in-the-loop HVDC test rig has been used to implement and validate the proposed damping scheme on an experimental platform. When faults occur within AC onshore networks, offshore MTDC networks are vulnerable to DC overvoltages, potentially damaging the DC plant and cables. Power reduction and power dissipation control systems were investigated to ride through onshore AC faults. These methods do not require dedicated fast communication systems. Simulations and laboratory experiments are carried out to evaluate the control systems, with the results from the two platforms compared..
30 CFR 57.12014 - Handling energized power cables.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Handling energized power cables. 57.12014... Electricity Surface and Underground § 57.12014 Handling energized power cables. Power cables energized to.... This does not prohibit pulling or dragging of cable by the equipment it powers when the cable is...
30 CFR 57.12014 - Handling energized power cables.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Handling energized power cables. 57.12014... Electricity Surface and Underground § 57.12014 Handling energized power cables. Power cables energized to.... This does not prohibit pulling or dragging of cable by the equipment it powers when the cable is...
30 CFR 57.12014 - Handling energized power cables.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Handling energized power cables. 57.12014... Electricity Surface and Underground § 57.12014 Handling energized power cables. Power cables energized to.... This does not prohibit pulling or dragging of cable by the equipment it powers when the cable is...
30 CFR 57.12014 - Handling energized power cables.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Handling energized power cables. 57.12014... Electricity Surface and Underground § 57.12014 Handling energized power cables. Power cables energized to.... This does not prohibit pulling or dragging of cable by the equipment it powers when the cable is...
30 CFR 57.12014 - Handling energized power cables.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Handling energized power cables. 57.12014... Electricity Surface and Underground § 57.12014 Handling energized power cables. Power cables energized to.... This does not prohibit pulling or dragging of cable by the equipment it powers when the cable is...
30 CFR 75.607 - Breaking trailing cable and power cable connections.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Breaking trailing cable and power cable... LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Trailing Cables § 75.607 Breaking trailing cable and power cable connections. [Statutory Provisions] Trailing cable and...
The influence of winding direction of two-layer HTS DC cable on the critical current
NASA Astrophysics Data System (ADS)
Vyatkin, V. S.; Kashiwagi, K.; Ivanov, Y. V.; Otabe, E. S.; Yamaguchi, S.
2017-09-01
The design of twist pitch and direction of winding in multilayer HTS coaxial cable is important. For HTS AC transmitting cables, the main condition of twist pitch is the balance of inductances of each layer for providing the current balance between layers. In this work, the finite element method analysis for the coaxial cables with both same and opposite directions winding is used to calculate magnetic field distribution, and critical current of the cable is estimated. It was found that the critical current of the cable with same direction winding is about 10 percent higher than that in the case of the cable with the opposite direction winding.
Sail GTS ground system analysis: Avionics system engineering
NASA Technical Reports Server (NTRS)
Lawton, R. M.
1977-01-01
A comparison of two different concepts for the guidance, navigation and control test set signal ground system is presented. The first is a concept utilizing a ground plate to which crew station, avionics racks, electrical power distribution system, master electrical common connection assembly and marshall mated elements system grounds are connected by 4/0 welding cable. An alternate approach has an aluminum sheet interconnecting the signal ground reference points between the crew station and avionics racks. The comparison analysis quantifies the differences between the two concepts in terms of dc resistance, ac resistance and inductive reactance. These parameters are figures of merit for ground system conductors in that the system with the lowest impedance is the most effective in minimizing noise voltage. Although the welding cable system is probably adequate, the aluminum sheet system provides a higher probability of a successful system design.
NASA Astrophysics Data System (ADS)
Sosnowski, M.; Eager, G. S., Jr.
1983-06-01
Threshold voltage of oil-impregnated paper insulated cables are investigaed. Experimental work was done on model cables specially manufactured for this project. The cables were impregnated with mineral and with synthetic oils. Standard impulse breakdown voltage tests and impulse voltage breakdown tests with dc prestressing were performed at room temperature and at 1000C. The most important result is the finding of very high level of threshold voltage stress for oil-impregnated paper insulated cables. This threshold voltage is approximately 1.5 times higher than the threshold voltage or crosslinked polyethylene insulated cables.
Power system analysis of Hanlim superconducting HVDC system using real time digital simulator
NASA Astrophysics Data System (ADS)
Won, Y. J.; Kim, J. G.; Kim, A. R.; Kim, G. H.; Park, M.; Yu, I. K.; Sim, K. D.; Cho, J.; Lee, S.; Jeong, K. W.; Watanabe, K.
2011-11-01
Jeju island is located approximately 100 km south from the mainland of Korea, and had a peak load of about 553 MW in 2008. The demand increases 7.2% a year over the last 5 years. Since the wind profiles of Jeju island are more favorable than mainland of Korea, many companies have shown interest in the wind power business at the Jeju island. Moreover KEPCO has a plan for renewable energy test too whose power will be delivered by HVDC system. One kilometer length of total 8 km was designed as superconducting DC cable. Rest 7 km will be the conventional overhead line. In this paper, the authors have developed a simulation model of the power network around 8 km HVDC system using real time digital simulator (RTDS).
Power supply system for the superconducting outsert of the CHMFL hybrid magnet
NASA Astrophysics Data System (ADS)
Fang, Z.; Zhu, J.; Chen, W.; Jiang, D.; Huang, P.; Chen, Z.; Tan, Y.; Kuang, G.
2017-12-01
The construction of a new hybrid magnet, consisting of a 11 T superconducting outsert and a 34 T resistive insert magnet, has been finished at the Chinese High Magnetic Field Laboratory (CHMFL) in Hefei. With a room temperature bore of 800 mm in diameter, the hybrid magnet superconducting outsert is composed of four separate Nb3Sn-based Cable-in-Conduit Conductor (CICC) coils electrically connected in series and powered by a single power supply system. The power supply system for the superconducting outsert consists of a 16 kA DC power supply, a quench protection system, a pair of 16 kA High Temperature Superconducting (HTS) current leads, and two Low Temperature Superconducting bus-lines. The design and manufacturing of the power supply system have been completed at the CHMFL. This paper describes the design features of the power supply system as well as the current fabrication condition of its main components.
Very Low Frequency Breakdown Properties of Electrical Insulation Materials at Cryogenic Temperatures
NASA Astrophysics Data System (ADS)
Sauers, I.; Tuncer, E.; Polizos, G.; James, D. R.; Ellis, A. R.; Pace, M. O.
2010-04-01
For long cables or equipment with large capacitance it is not always possible to conduct high voltage withstand tests at 60 Hz due to limitations in charging currents of the power supply. Very low frequency (typically at a frequency of 0.1 Hz) has been used for conventional cables as a way of getting around the charging current limitation. For superconducting grid applications the same issues apply. However there is very little data at cryogenic temperatures on how materials perform at low frequency compared to 60 Hz and whether higher voltages should be applied when performing a high voltage acceptability test. Various materials including G10 (fiberglass reinforced plastic or FRP), Cryoflex™ (a tape insulation used in some high temperature superconducting cables), kapton (commonly used polyimide), polycarbonate, and polyetherimide, and in liquid nitrogen alone have been tested using a step method for frequencies of 60 Hz, 0.1 Hz, and dc. The dwell time at each step was chosen so that the aging factor would be the same in both the 60 Hz and 0.1 Hz tests. The data indicated that, while there is a small frequency dependence for liquid nitrogen, there are significant differences for the solid materials studied. Breakdown data for these materials and for model cables will be shown and discussed.
Telecommunications in Africa: A Survey
ERIC Educational Resources Information Center
Editor
1977-01-01
Discusses a survey of thirty-eight African countries which indicates that a combination of co-axial cables and radio-relay links is the system most suited to Available from: Cable Lines, Cablecommunications Resource Center, 2000 K Street N.W., Washington, D.C. 20036; Subscription Rates: 1 year, $5.00; 2 years, $10.00. (MH)
78 FR 64213 - Information Collection Being Reviewed by the Federal Communications Commission
Federal Register 2010, 2011, 2012, 2013, 2014
2013-10-28
....1621, Equipment Compatibility Offer; Section 76.1622, Consumer Education of Equipment Compatibility... Commission, Media Bureau, Washington, DC 20554, and should include the name of the cable operator to whom the... on encryption of the basic service tier. This rule change allows all- digital cable operators to...
76 FR 72672 - Publication of Depreciation Rates
Federal Register 2010, 2011, 2012, 2013, 2014
2011-11-25
... cable--metal 5.10 g. Buried cable--fiber 5.00 h. Conduit systems 3.50 i. Other 5.50 Dated: November 19... ending December 31, 2011. FOR FURTHER INFORMATION CONTACT: Jonathan P. Claffey, Deputy Assistant... Avenue SW., Washington, DC 20250-1590. Telephone: (202) 720-9556. SUPPLEMENTARY INFORMATION: In 7 CFR...
Thermal analysis of underground power cable system
NASA Astrophysics Data System (ADS)
Rerak, Monika; Ocłoń, Paweł
2017-10-01
The paper presents the application of Finite Element Method in thermal analysis of underground power cable system. The computations were performed for power cables buried in-line in the ground at a depth of 2 meters. The developed mathematical model allows determining the two-dimensional temperature distribution in the soil, thermal backfill and power cables. The simulations studied the effect of soil and cable backfill thermal conductivity on the maximum temperature of the cable conductor. Also, the effect of cable diameter on the temperature of cable core was studied. Numerical analyses were performed based on a program written in MATLAB.
NASA Technical Reports Server (NTRS)
Behar, Alberto; Carsey, Frank; Lane, Arthur; Engelhardt, Herman
2006-01-01
An instrumentation system has been developed for studying interactions between a glacier or ice sheet and the underlying rock and/or soil. Prior borehole imaging systems have been used in well-drilling and mineral-exploration applications and for studying relatively thin valley glaciers, but have not been used for studying thick ice sheets like those of Antarctica. The system includes a cylindrical imaging probe that is lowered into a hole that has been bored through the ice to the ice/bedrock interface by use of an established hot-water-jet technique. The images acquired by the cameras yield information on the movement of the ice relative to the bedrock and on visible features of the lower structure of the ice sheet, including ice layers formed at different times, bubbles, and mineralogical inclusions. At the time of reporting the information for this article, the system was just deployed in two boreholes on the Amery ice shelf in East Antarctica and after successful 2000 2001 deployments in 4 boreholes at Ice Stream C, West Antarctica, and in 2002 at Black Rapids Glacier, Alaska. The probe is designed to operate at temperatures from 40 to +40 C and to withstand the cold, wet, high-pressure [130-atm (13.20-MPa)] environment at the bottom of a water-filled borehole in ice as deep as 1.6 km. A current version is being outfitted to service 2.4-km-deep boreholes at the Rutford Ice Stream in West Antarctica. The probe (see figure) contains a sidelooking charge-coupled-device (CCD) camera that generates both a real-time analog video signal and a sequence of still-image data, and contains a digital videotape recorder. The probe also contains a downward-looking CCD analog video camera, plus halogen lamps to illuminate the fields of view of both cameras. The analog video outputs of the cameras are converted to optical signals that are transmitted to a surface station via optical fibers in a cable. Electric power is supplied to the probe through wires in the cable at a potential of 170 VDC. A DC-to-DC converter steps the supply down to 12 VDC for the lights, cameras, and image-data-transmission circuitry. Heat generated by dissipation of electric power in the probe is removed simply by conduction through the probe housing to the visible features of the lower structure of the ice sheet, including ice layers formed at different times, bubbles, and mineralogical inclusions. At the time of reporting the information for this article, the system was just deployed in two boreholes on the Amery ice shelf in East Antarctica and after successful 2000 2001 deployments in 4 boreholes at Ice Stream C, West Antarctica, and in 2002 at Black Rapids Glacier, Alaska. The probe is designed to operate at temperatures from 40 to +40 C and to withstand the cold, wet, high-pressure [130-atm (13.20-MPa)] environment at the bottom of a water-filled borehole in ice as deep as 1.6 km. A current version is being outfitted to service 2.4-km-deep boreholes at the Rutford Ice Stream in West Antarctica. The probe (see figure) contains a sidelooking charge-coupled-device (CCD) camera that generates both a real-time analog video signal and a sequence of still-image data, and contains a digital videotape recorder. The probe also contains a downward-looking CCD analog video camera, plus halogen lamps to illuminate the fields of view of both cameras. The analog video outputs of the cameras are converted to optical signals that are transmitted to a surface station via optical fibers in a cable. Electric power is supplied to the probe through wires in the cable at a potential of 170 VDC. A DC-to-DC converter steps the supply down to 12 VDC for the lights, cameras, and image-datatransmission circuitry. Heat generated by dissipation of electric power in the probe is removed simply by conduction through the probe housing to the visible features of the lower structure of the ice sheet, including ice layers formed at different times, bubbles, and mineralogical inclusions. At thime of reporting the information for this article, the system was just deployed in two boreholes on the Amery ice shelf in East Antarctica and after successful 2000 2001 deployments in 4 boreholes at Ice Stream C, West Antarctica, and in 2002 at Black Rapids Glacier, Alaska. The probe is designed to operate at temperatures from 40 to +40 C and to withstand the cold, wet, high-pressure [130-atm (13.20-MPa)] environment at the bottom of a water-filled borehole in ice as deep as 1.6 km. A current version is being outfitted to service 2.4-km-deep boreholes at the Rutford Ice Stream in West Antarctica. The probe (see figure) contains a sidelooking charge-coupled-device (CCD) camera that generates both a real-time analog video signal and a sequence of still-image data, and contains a digital videotape recorder. The probe also contains a downward-looking CCD analog video camera, plus halogen lamps to illuminate the fields of view of both cameras. The analog video outputs of the cameras are converted to optical signals that are transmitted to a surface station via optical fibers in a cable. Electric power is supplied to the probe through wires in the cable at a potential of 170 VDC. A DC-to-DC converter steps the supply down to 12 VDC for the lights, cameras, and image-datatransmission circuitry. Heat generated by dissipation of electric power in the probe is removed simply by conduction through the probe housing to the adjacent water and ice.
Hybrid AC-High Voltage DC Grid Stability and Controls
NASA Astrophysics Data System (ADS)
Yu, Jicheng
The growth of energy demands in recent years has been increasing faster than the expansion of transmission facility construction. This tendency cooperating with the continuous investing on the renewable energy resources drives the research, development, and construction of HVDC projects to create a more reliable, affordable, and environmentally friendly power grid. Constructing the hybrid AC-HVDC grid is a significant move in the development of the HVDC techniques; the form of dc system is evolving from the point-to-point stand-alone dc links to the embedded HVDC system and the multi-terminal HVDC (MTDC) system. The MTDC is a solution for the renewable energy interconnections, and the MTDC grids can improve the power system reliability, flexibility in economic dispatches, and converter/cable utilizing efficiencies. The dissertation reviews the HVDC technologies, discusses the stability issues regarding the ac and HVDC connections, proposes a novel power oscillation control strategy to improve system stability, and develops a nonlinear voltage droop control strategy for the MTDC grid. To verify the effectiveness the proposed power oscillation control strategy, a long distance paralleled AC-HVDC transmission test system is employed. Based on the PSCAD/EMTDC platform simulation results, the proposed power oscillation control strategy can improve the system dynamic performance and attenuate the power oscillations effectively. To validate the nonlinear voltage droop control strategy, three droop controls schemes are designed according to the proposed nonlinear voltage droop control design procedures. These control schemes are tested in a hybrid AC-MTDC system. The hybrid AC-MTDC system, which is first proposed in this dissertation, consists of two ac grids, two wind farms and a five-terminal HVDC grid connecting them. Simulation studies are performed in the PSCAD/EMTDC platform. According to the simulation results, all the three design schemes have their unique salient features.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mueller Steffen; Wibbing Sascha; Weigel Robert
2015-07-01
Signal acquisition and data transmission for innovative sensor systems and networks inside the containment of nuclear power plants (NPPs) is still a challenge with respect to safety, performance, reliability, availability, and costs. This especially applies to equipment upgrades for existing plants, special measurements, but also for new builds. This paper presents a novel method for efficient and cost-effective sensor signal acquisition and data transmission via power lines, in order to cope with the disadvantages of common system architectures that often suffer from poor signal integrity due to raw data transmissions via long cables, huge efforts and costs for installation, andmore » low flexibility with respect to maintenance and upgrades. A transmitter-receiver architecture is proposed that allows multiplexing of multiple sensor inputs for unidirectional point-to-point transmission by superimposing information signals on existing AC or DC supply lines, but also on active and inactive sensor wires, or spare cables, using power line communication (PLC) technology. Based on commercial off-the-shelf (COTS) electronic parts, a radiation hard transmitter hardware is designed to operate in harsh environment within the containment during full plant operation. The system's modular approach allows application specific trade-offs between redundancy and throughput regarding data transmission, as well as various sensor input front-ends which are compatible with state of the art systems. PLC technology eliminates the need for costly installation of additional cables and wall penetrations, while providing a complementary and diverse communication technology for upgrades of existing systems. At the receiver side in low dose areas, signals are extracted from the power line, demodulated, and de-multiplexed, in order to regain the original sensor signal information and provide it either in analog or digital output format. Successful laboratory qualification tests, field trails, and a demonstrator setup installation within a NPP verify the overall performance of the proposed system. (authors)« less
High power cable with internal water cooling 400 kV
NASA Astrophysics Data System (ADS)
Rasquin, W.; Harjes, B.
1982-08-01
Due to the concentration of electricity production in large power plants, the need of higher power transmissions, and the protection of environment, developement of a 400 kV water cooled cable in the power range of 1 to 5 GVA was undertaken. The fabrication and testing of equipment, engineering of cable components, fabrication of a test cable, development of cable terminal laboratory, testing of test cable, field testing of test cable, fabrication of industrial cable laboratory, testing of industrial cable, field testing of industrial cable, and system analysis for optimization were prepared. The field testing was impossible to realize. However, it is proved that a cable consisting of an internal stainless steel water cooled tube, covered by stranded copper profiles, insulated with heavy high quality paper, and protected by an aluminum cover can be produced, withstand tests accordingly to IEC/VDE recommendations, and is able to fulfill all exploitation conditions.
Photonic-powered cable assembly
Sanderson, Stephen N.; Appel, Titus James; Wrye, IV, Walter C.
2013-01-22
A photonic-cable assembly includes a power source cable connector ("PSCC") coupled to a power receive cable connector ("PRCC") via a fiber cable. The PSCC electrically connects to a first electronic device and houses a photonic power source and an optical data transmitter. The fiber cable includes an optical transmit data path coupled to the optical data transmitter, an optical power path coupled to the photonic power source, and an optical feedback path coupled to provide feedback control to the photonic power source. The PRCC electrically connects to a second electronic device and houses an optical data receiver coupled to the optical transmit data path, a feedback controller coupled to the optical feedback path to control the photonic power source, and a photonic power converter coupled to the optical power path to convert photonic energy received over the optical power path to electrical energy to power components of the PRCC.
Photonic-powered cable assembly
Sanderson, Stephen N; Appel, Titus James; Wrye, IV, Walter C
2014-06-24
A photonic-cable assembly includes a power source cable connector ("PSCC") coupled to a power receive cable connector ("PRCC") via a fiber cable. The PSCC electrically connects to a first electronic device and houses a photonic power source and an optical data transmitter. The fiber cable includes an optical transmit data path coupled to the optical data transmitter, an optical power path coupled to the photonic power source, and an optical feedback path coupled to provide feedback control to the photonic power source. The PRCC electrically connects to a second electronic device and houses an optical data receiver coupled to the optical transmit data path, a feedback controller coupled to the optical feedback path to control the photonic power source, and a photonic power converter coupled to the optical power path to convert photonic energy received over the optical power path to electrical energy to power components of the PRCC.
30 CFR 75.517 - Power wires and cables; insulation and protection.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Power wires and cables; insulation and...-General § 75.517 Power wires and cables; insulation and protection. [Statutory Provisions] Power wires and cables, except trolley wires, trolley feeder wires, and bare signal wires, shall be insulated adequately...
30 CFR 75.517 - Power wires and cables; insulation and protection.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Power wires and cables; insulation and...-General § 75.517 Power wires and cables; insulation and protection. [Statutory Provisions] Power wires and cables, except trolley wires, trolley feeder wires, and bare signal wires, shall be insulated adequately...
30 CFR 75.517 - Power wires and cables; insulation and protection.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Power wires and cables; insulation and...-General § 75.517 Power wires and cables; insulation and protection. [Statutory Provisions] Power wires and cables, except trolley wires, trolley feeder wires, and bare signal wires, shall be insulated adequately...
30 CFR 75.517 - Power wires and cables; insulation and protection.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Power wires and cables; insulation and...-General § 75.517 Power wires and cables; insulation and protection. [Statutory Provisions] Power wires and cables, except trolley wires, trolley feeder wires, and bare signal wires, shall be insulated adequately...
30 CFR 75.517 - Power wires and cables; insulation and protection.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Power wires and cables; insulation and...-General § 75.517 Power wires and cables; insulation and protection. [Statutory Provisions] Power wires and cables, except trolley wires, trolley feeder wires, and bare signal wires, shall be insulated adequately...
Flow-Induced Oscillations of OTEC Mooring and Anchoring Cables: State of the Art.
1982-05-27
general, including heat exchangers , overhead transmission lines, and marine structures and cables. A flowchart that describes the steps necessary to...34Crossflow-Induced Vibrations of Heat Exchanger Tube Banks," Nuc. Engrg. and Design, Vol. 47, 67-86, 1978. 22. O.M. Griffin and S.E. Ramberg, "On...AD-AIlS 462 NAVAL RESEARCH LAB WASHINGTON DC F/6 13/13 FLOW-INOUCED OSCILLATIONS OF OTEC MOORING AND ANCHORING CABLES --ETC(UI MAY 62 0 M GRIFFIN
Power inverter with optical isolation
Duncan, Paul G.; Schroeder, John Alan
2005-12-06
An optically isolated power electronic power conversion circuit that includes an input electrical power source, a heat pipe, a power electronic switch or plurality of interconnected power electronic switches, a mechanism for connecting the switch to the input power source, a mechanism for connecting comprising an interconnecting cable and/or bus bar or plurality of interconnecting cables and/or input bus bars, an optically isolated drive circuit connected to the switch, a heat sink assembly upon which the power electronic switch or switches is mounted, an output load, a mechanism for connecting the switch to the output load, the mechanism for connecting including an interconnecting cable and/or bus bar or plurality of interconnecting cables and/or output bus bars, at least one a fiber optic temperature sensor mounted on the heat sink assembly, at least one fiber optic current sensor mounted on the load interconnection cable and/or output bus bar, at least one fiber optic voltage sensor mounted on the load interconnection cable and/or output bus bar, at least one fiber optic current sensor mounted on the input power interconnection cable and/or input bus bar, and at least one fiber optic voltage sensor mounted on the input power interconnection cable and/or input bus bar.
30 CFR 57.12013 - Splices and repairs of power cables.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Splices and repairs of power cables. 57.12013... Electricity Surface and Underground § 57.12013 Splices and repairs of power cables. Permanent splices and repairs made in power cables, including the ground conductor where provided, shall be— (a) Mechanically...
30 CFR 57.12013 - Splices and repairs of power cables.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Splices and repairs of power cables. 57.12013... Electricity Surface and Underground § 57.12013 Splices and repairs of power cables. Permanent splices and repairs made in power cables, including the ground conductor where provided, shall be— (a) Mechanically...
30 CFR 56.12008 - Insulation and fittings for power wires and cables.
Code of Federal Regulations, 2014 CFR
2014-07-01
... MINES Electricity § 56.12008 Insulation and fittings for power wires and cables. Power wires and cables... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Insulation and fittings for power wires and cables. 56.12008 Section 56.12008 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF...
30 CFR 56.12008 - Insulation and fittings for power wires and cables.
Code of Federal Regulations, 2013 CFR
2013-07-01
... MINES Electricity § 56.12008 Insulation and fittings for power wires and cables. Power wires and cables... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Insulation and fittings for power wires and cables. 56.12008 Section 56.12008 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF...
30 CFR 56.12008 - Insulation and fittings for power wires and cables.
Code of Federal Regulations, 2012 CFR
2012-07-01
... MINES Electricity § 56.12008 Insulation and fittings for power wires and cables. Power wires and cables... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Insulation and fittings for power wires and cables. 56.12008 Section 56.12008 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF...
30 CFR 57.12013 - Splices and repairs of power cables.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Splices and repairs of power cables. 57.12013... Electricity Surface and Underground § 57.12013 Splices and repairs of power cables. Permanent splices and repairs made in power cables, including the ground conductor where provided, shall be— (a) Mechanically...
30 CFR 57.12013 - Splices and repairs of power cables.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Splices and repairs of power cables. 57.12013... Electricity Surface and Underground § 57.12013 Splices and repairs of power cables. Permanent splices and repairs made in power cables, including the ground conductor where provided, shall be— (a) Mechanically...
30 CFR 57.12013 - Splices and repairs of power cables.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Splices and repairs of power cables. 57.12013... Electricity Surface and Underground § 57.12013 Splices and repairs of power cables. Permanent splices and repairs made in power cables, including the ground conductor where provided, shall be— (a) Mechanically...
30 CFR 56.12008 - Insulation and fittings for power wires and cables.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Insulation and fittings for power wires and... MINES Electricity § 56.12008 Insulation and fittings for power wires and cables. Power wires and cables... insulated wires, other than cables, pass through metal frames, the holes shall be substantially bushed with...
30 CFR 56.12008 - Insulation and fittings for power wires and cables.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Insulation and fittings for power wires and... MINES Electricity § 56.12008 Insulation and fittings for power wires and cables. Power wires and cables... insulated wires, other than cables, pass through metal frames, the holes shall be substantially bushed with...
30 CFR 75.517-1 - Power wires and cables; insulation and protection.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Power wires and cables; insulation and protection. 75.517-1 Section 75.517-1 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF...-General § 75.517-1 Power wires and cables; insulation and protection. Power wires and cables installed on...
30 CFR 75.517-1 - Power wires and cables; insulation and protection.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Power wires and cables; insulation and protection. 75.517-1 Section 75.517-1 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF...-General § 75.517-1 Power wires and cables; insulation and protection. Power wires and cables installed on...
30 CFR 57.12083 - Support of power cables in shafts and boreholes.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Support of power cables in shafts and boreholes... NONMETAL MINES Electricity Underground Only § 57.12083 Support of power cables in shafts and boreholes. Power cables in shafts and boreholes shall be fastened securely in such a manner as to prevent undue...
30 CFR 57.12083 - Support of power cables in shafts and boreholes.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Support of power cables in shafts and boreholes... NONMETAL MINES Electricity Underground Only § 57.12083 Support of power cables in shafts and boreholes. Power cables in shafts and boreholes shall be fastened securely in such a manner as to prevent undue...
30 CFR 57.12083 - Support of power cables in shafts and boreholes.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Support of power cables in shafts and boreholes... NONMETAL MINES Electricity Underground Only § 57.12083 Support of power cables in shafts and boreholes. Power cables in shafts and boreholes shall be fastened securely in such a manner as to prevent undue...
30 CFR 57.12083 - Support of power cables in shafts and boreholes.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Support of power cables in shafts and boreholes... NONMETAL MINES Electricity Underground Only § 57.12083 Support of power cables in shafts and boreholes. Power cables in shafts and boreholes shall be fastened securely in such a manner as to prevent undue...
30 CFR 57.12083 - Support of power cables in shafts and boreholes.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Support of power cables in shafts and boreholes... NONMETAL MINES Electricity Underground Only § 57.12083 Support of power cables in shafts and boreholes. Power cables in shafts and boreholes shall be fastened securely in such a manner as to prevent undue...
30 CFR 75.517-1 - Power wires and cables; insulation and protection.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Power wires and cables; insulation and protection. 75.517-1 Section 75.517-1 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF...-General § 75.517-1 Power wires and cables; insulation and protection. Power wires and cables installed on...
30 CFR 75.517-1 - Power wires and cables; insulation and protection.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Power wires and cables; insulation and protection. 75.517-1 Section 75.517-1 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF...-General § 75.517-1 Power wires and cables; insulation and protection. Power wires and cables installed on...
30 CFR 75.517-1 - Power wires and cables; insulation and protection.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Power wires and cables; insulation and protection. 75.517-1 Section 75.517-1 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF...-General § 75.517-1 Power wires and cables; insulation and protection. Power wires and cables installed on...
A modified quadrupole mass spectrometer with custom RF link rods driver for remote operation
NASA Technical Reports Server (NTRS)
Tashbar, P. W.; Nisen, D. B.; Moore, W. W., Jr.
1973-01-01
A commercial quadrupole residual gas analyzer system has been upgraded for operation at extended cable lengths. Operation inside a vacuum chamber for the standard quadrupole nude head is limited to approximately 2 m from its externally located rf/dc generator because of the detuning of the rf oscillator circuits by the coaxial cable reactance. The advance of long distance remote operation inside a vacuum chamber for distances of 45 and 60 m was made possible without altering the quadrupole's rf/dc generator circuit by employing an rf link to drive the quadrupole rods. Applications of the system have been accomplished for in situ space simulation thermal/vacuum testing of sophisticated payloads.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Trailing cables supplying power to low-voltage... Alternating Current Circuits § 77.906 Trailing cables supplying power to low-voltage mobile equipment; ground wires and ground check wires. On and after September 30, 1971, all trailing cables supplying power to...
30 CFR 75.517-2 - Plans for insulation of existing bare power wires and cables.
Code of Federal Regulations, 2013 CFR
2013-07-01
... Equipment-General § 75.517-2 Plans for insulation of existing bare power wires and cables. (a) On or before December 31, 1970, plans for the insulation of existing bare power wires and cables installed prior to... officials; (2) Map or diagram indicating location of power wires and cables required to be insulated; (3...
30 CFR 75.517-2 - Plans for insulation of existing bare power wires and cables.
Code of Federal Regulations, 2014 CFR
2014-07-01
... Equipment-General § 75.517-2 Plans for insulation of existing bare power wires and cables. (a) On or before December 31, 1970, plans for the insulation of existing bare power wires and cables installed prior to... officials; (2) Map or diagram indicating location of power wires and cables required to be insulated; (3...
Code of Federal Regulations, 2012 CFR
2012-07-01
... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Trailing cables supplying power to low-voltage... Alternating Current Circuits § 77.906 Trailing cables supplying power to low-voltage mobile equipment; ground wires and ground check wires. On and after September 30, 1971, all trailing cables supplying power to...
30 CFR 75.517-2 - Plans for insulation of existing bare power wires and cables.
Code of Federal Regulations, 2012 CFR
2012-07-01
... Equipment-General § 75.517-2 Plans for insulation of existing bare power wires and cables. (a) On or before December 31, 1970, plans for the insulation of existing bare power wires and cables installed prior to... officials; (2) Map or diagram indicating location of power wires and cables required to be insulated; (3...
Code of Federal Regulations, 2014 CFR
2014-07-01
... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Trailing cables supplying power to low-voltage... Alternating Current Circuits § 77.906 Trailing cables supplying power to low-voltage mobile equipment; ground wires and ground check wires. On and after September 30, 1971, all trailing cables supplying power to...
Assessing potential impacts of energized submarine power cables on crab harvests
NASA Astrophysics Data System (ADS)
Love, Milton S.; Nishimoto, Mary M.; Clark, Scott; McCrea, Merit; Bull, Ann Scarborough
2017-12-01
Offshore renewable energy facilities transmit electricity to shore through submarine power cables. Electromagnetic field emissions (EMFs) are generated from the transmission of electricity through these cables, such as the AC inter-array (between unit) and AC export (to shore) cables often used in offshore energy production. The EMF has both an electric component and a magnetic component. While sheathing can block the direct electric field, the magnetic field is not blocked. A concern raised by fishermen on the Pacific Coast of North America is that commercially important Dungeness crab (Metacarcinus magister Dana, 1852)) might not cross over an energized submarine power cable to enter a baited crab trap, thus potentially reducing their catch. The presence of operating energized cables off southern California and in Puget Sound (cables that are comparable to those within the arrays of existing offshore wind energy devices) allowed us to conduct experiments on how energized power cables might affect the harvesting of both M. magister and another commercially important crab species, Cancer productus Randall, 1839. In this study we tested the questions: 1) Is the catchability of crabs reduced if these animals must traverse an energized power cable to enter a trap and 2) if crabs preferentially do not cross an energized cable, is it the cable structure or the EMF emitted from that cable that deters crabs from crossing? In field experiments off southern California and in Puget Sound, crabs were given a choice of walking over an energized power cable to a baited trap or walking directly away from that cable to a second baited trap. Based on our research we found no evidence that the EMF emitted by energized submarine power cables influenced the catchability of these two species of commercially important crabs. In addition, there was no difference in the crabs' responses to lightly buried versus unburied cables. We did observe that, regardless of the position of the cable, Cancer productus in southern California tended to move to the west and Metacarcinus magister tended to move to the east.
NASA Astrophysics Data System (ADS)
Yamaguchi, S.; Ivanov, Y.; Watanabe, H.; Chikumoto, N.; Koshiduka, H.; Hayashi, K.; Sawamura, T.
Ishikari project constructs two lines. The length of the Line 1 is 500 m, and connects the photovoltaic cell to the internet-data center. The other line is 1 km length, and it is a test facility and called Line 2. The structures of the cable systems are not same to test their performance. The construction was started from 2014 in the field, the Line 1 was completed in May 2015, and it was cooled down and do the current experiment, and warmed up. The Line 2 is almost complete in October 2015. It will be tested in November and December, 2015. In order to reduce the stress of the cable induced by the thermal expansion and contraction, we adopted the way of the helical deformation of the cable. The force of the cable is reduced to 1/3 of an usual cable test. Because the cryogenic pipes are welded in the field and we cannot use the baking of the vacuum chamber of the cryogenic pipe, a new vacuum pumping method was proposed and tested for the cryogenic pipe. Since the straight pipes are used to compose the cryogenic pipe, the pressure drop of the circulation would be 1/100 of the corrugated pipe in the present condition, and it is suitable for longer cable system. The heat leak of the cryogenic pipe is ∼1.4W/m including the cable pipe's and the return pipe's. The heat leak of the current lead is ∼30W/kA in the test bench. Finally the current of 6kA/3 sec and the current of 5kA/15 min were achieved in Line 1. The reduction of heat leak will be a major subject of the longer cable system. The cost of the construction will be almost twice higher than that of the copper and aluminum over-head line with the iron tower in the present Japan. The cost construction of the over-head line is an average value, and depends on the newspaper.
NASA Astrophysics Data System (ADS)
Kasinski, K.; Koczon, P.; Ayet, S.; Löchner, S.; Schmidt, C. J.
2017-03-01
New fixed target experiments using high intensity beams with energy up to 10 AGeV from the SIS100 synchrotron presently being constructed at FAIR/GSI are under preparation. Most of the readout electronics and power supplies are expected to be exposed to a very high flux of nuclear reaction products and have to be radiation tolerant up to 3 MRad (TID) and sustain up to 1014/cm2 of 1 MeV neutron equivalent in their life time. Moreover, the mostly minimum ionising particles under investigation leave very little signal in the sensors. Therefore very low noise level amplitude measurements are required by the front-end electronics for effective tracking. Sensor and interconnecting micro-cable capacitance and series resistance in conjunction with intrinsic noise of the charge sensitive amplifier are dominant noise sources in the system. However, the single-ended architecture of the amplifiers employed for the charge processing channels implies a potential problem with noise contributions from power supply sources. Strict system-level constraints leave very little freedom in selecting a power supply structure optimal with respect to: power efficiency, cooling capabilities and power density on modules, but also noise injection to the front-end via the power supply lines. Design of the power supply and distribution system of the Silicon Tracking System in the CBM experiment together with details on the front-end ASICs (STS -XYTER2) and measurement results of power supply and conditioning electronics (selected DC/DC converter and LDO regulators) are presented.
30 CFR 57.12008 - Insulation and fittings for power wires and cables.
Code of Federal Regulations, 2014 CFR
2014-07-01
... cables. Power wires and cables shall be insulated adequately where they pass into or out of electrical... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Insulation and fittings for power wires and cables. 57.12008 Section 57.12008 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF...
30 CFR 57.12008 - Insulation and fittings for power wires and cables.
Code of Federal Regulations, 2013 CFR
2013-07-01
... cables. Power wires and cables shall be insulated adequately where they pass into or out of electrical... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Insulation and fittings for power wires and cables. 57.12008 Section 57.12008 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF...
30 CFR 57.12008 - Insulation and fittings for power wires and cables.
Code of Federal Regulations, 2012 CFR
2012-07-01
... cables. Power wires and cables shall be insulated adequately where they pass into or out of electrical... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Insulation and fittings for power wires and cables. 57.12008 Section 57.12008 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF...
Ames Lab 101: Reinventing the Power Cable
Russell, Alan
2018-01-16
Ames Laboratory researchers are working to develop new electrical power cables that are stronger and lighter than the cables currently used in the nation's power grid. Nano Tube animation by Iain Goodyear
Design of power cable grounding wire anti-theft monitoring system
NASA Astrophysics Data System (ADS)
An, Xisheng; Lu, Peng; Wei, Niansheng; Hong, Gang
2018-01-01
In order to prevent the serious consequences of the power grid failure caused by the power cable grounding wire theft, this paper presents a GPRS based power cable grounding wire anti-theft monitoring device system, which includes a camera module, a sensor module, a micro processing system module, and a data monitoring center module, a mobile terminal module. Our design utilize two kinds of methods for detecting and reporting comprehensive image, it can effectively solve the problem of power and cable grounding wire box theft problem, timely follow-up grounded cable theft events, prevent the occurrence of electric field of high voltage transmission line fault, improve the reliability of the safe operation of power grid.
NASA Astrophysics Data System (ADS)
Bull, A. S.; Nishimoto, M.; Love, M.; Schroeder, D. M.
2016-02-01
A network of power cables is an important component of any offshore renewable energy generation facilities (e.g., wind and wave). The cables laid on the seafloor carry current that produces both electric and magnetic fields; the magnetic field, here called an electromagnetic field (EMF), is what is emitted from shielded cables. The cables, themselves, add hard, low-relief structure to what is typically soft-bottom habitat (mud or sand). Given that laboratory experiments show EMF can affect the behavior of some marine vertebrates and invertebrates, concern is raised over the potential ecological impacts of in situ power cables. Here we report an unusual comparative study of the effect of EMF emitted from in situ power cables on the fish and invertebrate communities of the deep coastal shelf environment. In the Santa Barbara Channel of southern California, subsea power cables, similar to those used in the offshore renewable energy industry, transmit electricity from shore to offshore oil and gas production platforms. A non-energized cable in the vicinity of energized cables afforded us the unusual opportunity to control for the effect of cable as hard, low relief habitat. We conducted three annual submersible surveys in October, 2012- 2014, at depths from 75 m to 210 m. We present results comparing observations along the energized and nonenergized cables and on the adjacent natural substrate.
47 CFR 15.213 - Cable locating equipment.
Code of Federal Regulations, 2012 CFR
2012-10-01
...: Within the frequency band 9 kHz, up to, but not including, 45 kHz, the peak output power from the cable... output power from the cable locating equipment shall not exceed one watt. If provisions are made for connection of the cable locating equipment to the AC power lines, the conducted limits in § 15.207 also apply...
47 CFR 15.213 - Cable locating equipment.
Code of Federal Regulations, 2013 CFR
2013-10-01
...: Within the frequency band 9 kHz, up to, but not including, 45 kHz, the peak output power from the cable... output power from the cable locating equipment shall not exceed one watt. If provisions are made for connection of the cable locating equipment to the AC power lines, the conducted limits in § 15.207 also apply...
47 CFR 15.213 - Cable locating equipment.
Code of Federal Regulations, 2014 CFR
2014-10-01
...: Within the frequency band 9 kHz, up to, but not including, 45 kHz, the peak output power from the cable... output power from the cable locating equipment shall not exceed one watt. If provisions are made for connection of the cable locating equipment to the AC power lines, the conducted limits in § 15.207 also apply...
47 CFR 15.213 - Cable locating equipment.
Code of Federal Regulations, 2011 CFR
2011-10-01
...: Within the frequency band 9 kHz, up to, but not including, 45 kHz, the peak output power from the cable... output power from the cable locating equipment shall not exceed one watt. If provisions are made for connection of the cable locating equipment to the AC power lines, the conducted limits in § 15.207 also apply...
Power superconducting power transmission cable
Ashworth, Stephen P.
2003-06-10
The present invention is for a compact superconducting power transmission cable operating at distribution level voltages. The superconducting cable is a conductor with a number of tapes assembled into a subconductor. These conductors are then mounted co-planarly in an elongated dielectric to produce a 3-phase cable. The arrangement increases the magnetic field parallel to the tapes thereby reducing ac losses.
Power superconducting power transmission cable
Ashworth, Stephen P.
2003-01-01
The present invention is for a compact superconducting power transmission cable operating at distribution level voltages. The superconducting cable is a conductor with a number of tapes assembled into a subconductor. These conductors are then mounted co-planarly in an elongated dielectric to produce a 3-phase cable. The arrangement increases the magnetic field parallel to the tapes thereby reducing ac losses.
Study on Safety Monitoring System for Submarine Power Cable on the Basis of AIS and Radar Technology
NASA Astrophysics Data System (ADS)
Jie, Wang; Yao-Tian, Fan
Through analyzing the risks of submarine power cable, the highest risk to damage the cable identified is from ship. Based on concept of Vessel Traffic Management Information Systems, the three core sub-systems of safety monitoring system for submarine power cable were studied and described, also some suggestions were given.
30 CFR Appendix I to Subpart D of... - Appendix I to Subpart D of Part 18
Code of Federal Regulations, 2012 CFR
2012-07-01
... LIST OF TABLES Table No. Title 1 Portable power cable ampacities—600 volts. 2 Portable cord ampacities—600 volts. 3 Portable power cable ampacities—601 to 5,000 volts. 4 Normal diameter of round cables... diameter of three-conductor portable power cables with tolerances in inches—601 to 5,000 volts. 8 Fuse...
30 CFR Appendix I to Subpart D of... - Appendix I to Subpart D of Part 18
Code of Federal Regulations, 2014 CFR
2014-07-01
... LIST OF TABLES Table No. Title 1 Portable power cable ampacities—600 volts. 2 Portable cord ampacities—600 volts. 3 Portable power cable ampacities—601 to 5,000 volts. 4 Normal diameter of round cables... diameter of three-conductor portable power cables with tolerances in inches—601 to 5,000 volts. 8 Fuse...
30 CFR 75.517-2 - Plans for insulation of existing bare power wires and cables.
Code of Federal Regulations, 2010 CFR
2010-07-01
... wires and cables. 75.517-2 Section 75.517-2 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION... Equipment-General § 75.517-2 Plans for insulation of existing bare power wires and cables. (a) On or before December 31, 1970, plans for the insulation of existing bare power wires and cables installed prior to...
30 CFR 75.517-2 - Plans for insulation of existing bare power wires and cables.
Code of Federal Regulations, 2011 CFR
2011-07-01
... wires and cables. 75.517-2 Section 75.517-2 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION... Equipment-General § 75.517-2 Plans for insulation of existing bare power wires and cables. (a) On or before December 31, 1970, plans for the insulation of existing bare power wires and cables installed prior to...
Nondestructive Examination for Nuclear Power Plant Cable Aging Management Programs
DOE Office of Scientific and Technical Information (OSTI.GOV)
Glass, Samuel W.; Fifield, Leonard S.
2016-01-01
Degradation of the cable jacket, electrical insulation, and other cable components of installed cables within nuclear power plants (NPPs) is known to occur as a function of age, temperature, radiation, and other environmental factors. System tests verify cable function under normal loads; however, the concern is over cable performance under exceptional loads associated with design-basis events (DBEs). The cable’s ability to perform safely over the initial 40 year planned and licensed life has generally been demonstrated and there have been very few age-related cable failures. With greater than 1000 km of power, control, instrumentation, and other cables typically found inmore » an NPP, replacing all the cables would be a severe cost burden. Justification for life extension to 60 and 80 years requires a cable aging management program (AMP) to justify cable performance under normal operation as well as accident conditions. This paper addresses various NDE technologies that constitute the essence of an acceptable aging management program.« less
52. View of sitdown cable car, cable way, and stream ...
52. View of sit-down cable car, cable way, and stream gaging station, looking southeast. Photo by Robin Lee Tedder, Puget Power, 1989. - Puget Sound Power & Light Company, White River Hydroelectric Project, 600 North River Avenue, Dieringer, Pierce County, WA
51. View of sitdown cable car and cable way for ...
51. View of sit-down cable car and cable way for stream gaging, looking west. Photo by Robin Lee Tedder, Puget Power, 1989. - Puget Sound Power & Light Company, White River Hydroelectric Project, 600 North River Avenue, Dieringer, Pierce County, WA
NASA Technical Reports Server (NTRS)
Sarma, Garimella R.; Barranger, John P.
1992-01-01
The analysis and prototype results of a dual-amplifier circuit for measuring blade-tip clearance in turbine engines are presented. The capacitance between the blade tip and mounted capacitance electrode within a guard ring of a probe forms one of the feedback elements of an operational amplifier (op amp). The differential equation governing the circuit taking into consideration the nonideal features of the op amp was formulated and solved for two types of inputs (ramp and dc) that are of interest for the application. Under certain time-dependent constraints, it is shown that (1) with a ramp input the circuit has an output voltage proportional to the static tip clearance capacitance, and (2) with a dc input, the output is proportional to the derivative of the clearance capacitance, and subsequent integration recovers the dynamic capacitance. The technique accommodates long cable lengths and environmentally induced changes in cable and probe parameters. System implementation for both static and dynamic measurements having the same high sensitivity is also presented.
NASA Astrophysics Data System (ADS)
Sarma, Garimella R.; Barranger, John P.
1992-10-01
The analysis and prototype results of a dual-amplifier circuit for measuring blade-tip clearance in turbine engines are presented. The capacitance between the blade tip and mounted capacitance electrode within a guard ring of a probe forms one of the feedback elements of an operational amplifier (op amp). The differential equation governing the circuit taking into consideration the nonideal features of the op amp was formulated and solved for two types of inputs (ramp and dc) that are of interest for the application. Under certain time-dependent constraints, it is shown that (1) with a ramp input the circuit has an output voltage proportional to the static tip clearance capacitance, and (2) with a dc input, the output is proportional to the derivative of the clearance capacitance, and subsequent integration recovers the dynamic capacitance. The technique accommodates long cable lengths and environmentally induced changes in cable and probe parameters. System implementation for both static and dynamic measurements having the same high sensitivity is also presented.
A Practical Study of the 66kV Fault Current Limiter (FCL) System with Rectifier
NASA Astrophysics Data System (ADS)
Tokuda, Noriaki; Matsubara, Yoshio; Yuguchi, Kyosuke; Ohkuma, Takeshi; Hobara, Natsuro; Takahashi, Yoshihisa
A fault current limiter (FCL) is extensively expected to suppress fault current, particularly required for trunk power systems heavily connected high-voltage transmission lines, such as 500kV class power system which constitutes the nucleus of the electric power system. By installing such FCL in the power system, the system interconnection is possible without the need to raise the capacity of the circuit breakers, and facilities can be configured for efficiency, among other benefits. For these reasons, fault current limiters based on various principles of operation have been developed both in Japan and abroad. In this paper, we have proposed a new type of FCL system, consisting of solid-state diodes, DC coil and bypass AC coil, and described the specification of distribution power system and 66kV model at the island power system and the superconducting cable power system. Also we have made a practical study of 66kV class, which is the testing items and the future subjects of the rectifier type FCL system.
Fluid flow rate control device
NASA Technical Reports Server (NTRS)
Reinicke, Robert H. (Inventor); Mohtar, Rafic (Inventor); Nelson, Richard O. (Inventor)
1991-01-01
A poppet is modulated between closed and full open positions by a brushless DC motor operating magnetically through a housing to drive a permanent magnet rotor which carries the poppet. The rotor is supported on several parallel cables which are stationarily fixed at one end and attached to the rotor at the other end, whereby rotation of the rotor twists the cables, causing axial foreshortening and axial translation of rotor and poppet. Axial translation is enhanced by placing a spacer between the cables, intermediate their ends. A permanent magnet ring is disposed around the valve seat directly axially attracting the rotor to a valve closed position.
Strain relief for power-cable connectors
NASA Technical Reports Server (NTRS)
Dean, W. T., III
1980-01-01
Easily fabricated grommet composed of polytetrafluoroethylene cylinder, containing U-shaped channels equally spaced around periphery, is used in power cable connectors to relieve strain on cables. Utilization of grommets provides more ease in cable insertion and removal. Potential applications include wiring in large residential and commercial buildings.
30 CFR 75.1905-1 - Diesel fuel piping systems.
Code of Federal Regulations, 2013 CFR
2013-07-01
... entry as electric cables or power lines. Where it is necessary for piping systems to cross electric cables or power lines, guarding must be provided to prevent severed electrical cables or power lines near... storage facility. (h) The diesel fuel piping system must not be located in a borehole with electric power...
30 CFR 75.1905-1 - Diesel fuel piping systems.
Code of Federal Regulations, 2014 CFR
2014-07-01
... entry as electric cables or power lines. Where it is necessary for piping systems to cross electric cables or power lines, guarding must be provided to prevent severed electrical cables or power lines near... storage facility. (h) The diesel fuel piping system must not be located in a borehole with electric power...
30 CFR 57.12008 - Insulation and fittings for power wires and cables.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Insulation and fittings for power wires and... NONMETAL MINES Electricity Surface and Underground § 57.12008 Insulation and fittings for power wires and cables. Power wires and cables shall be insulated adequately where they pass into or out of electrical...
30 CFR 57.12008 - Insulation and fittings for power wires and cables.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Insulation and fittings for power wires and... NONMETAL MINES Electricity Surface and Underground § 57.12008 Insulation and fittings for power wires and cables. Power wires and cables shall be insulated adequately where they pass into or out of electrical...
77 FR 24228 - Condition Monitoring Techniques for Electric Cables Used in Nuclear Power Plants
Federal Register 2010, 2011, 2012, 2013, 2014
2012-04-23
... Used in Nuclear Power Plants AGENCY: Nuclear Regulatory Commission. ACTION: Regulatory guide; issuance... guide, (RG) 1.218, ``Condition Monitoring Techniques for Electric Cables Used in Nuclear Power Plants... of electric cables for nuclear power plants. RG 1.218 is not intended to be prescriptive, instead it...
WASTE HANDLING BUILDING ELECTRICAL SYSTEM DESCRIPTION DOCUMENT
DOE Office of Scientific and Technical Information (OSTI.GOV)
S.C. Khamamkar
2000-06-23
The Waste Handling Building Electrical System performs the function of receiving, distributing, transforming, monitoring, and controlling AC and DC power to all waste handling building electrical loads. The system distributes normal electrical power to support all loads that are within the Waste Handling Building (WHB). The system also generates and distributes emergency power to support designated emergency loads within the WHB within specified time limits. The system provides the capability to transfer between normal and emergency power. The system provides emergency power via independent and physically separated distribution feeds from the normal supply. The designated emergency electrical equipment will bemore » designed to operate during and after design basis events (DBEs). The system also provides lighting, grounding, and lightning protection for the Waste Handling Building. The system is located in the Waste Handling Building System. The system consists of a diesel generator, power distribution cables, transformers, switch gear, motor controllers, power panel boards, lighting panel boards, lighting equipment, lightning protection equipment, control cabling, and grounding system. Emergency power is generated with a diesel generator located in a QL-2 structure and connected to the QL-2 bus. The Waste Handling Building Electrical System distributes and controls primary power to acceptable industry standards, and with a dependability compatible with waste handling building reliability objectives for non-safety electrical loads. It also generates and distributes emergency power to the designated emergency loads. The Waste Handling Building Electrical System receives power from the Site Electrical Power System. The primary material handling power interfaces include the Carrier/Cask Handling System, Canister Transfer System, Assembly Transfer System, Waste Package Remediation System, and Disposal Container Handling Systems. The system interfaces with the MGR Operations Monitoring and Control System for supervisory monitoring and control signals. The system interfaces with all facility support loads such as heating, ventilation, and air conditioning, office, fire protection, monitoring and control, safeguards and security, and communications subsystems.« less
JPS heater and sensor lightning qualification
NASA Technical Reports Server (NTRS)
Cook, M.
1989-01-01
Simulated lightning strike testing of the Redesigned Solid Rocket Motor (RSRM) field joint protection system heater assembly was performed at Thiokol Corp., Wendover Lightning Facility. Testing consisted of subjecting the lightning evaluation test article to simulated lightning strikes and evaluating the effects of heater cable transients on cables within the systems tunnel. The maximum short circuit current coupled onto a United Space Boosters, Inc. operational flight cable within the systems tunnel, induced by transients from all cables external to the systems tunnel, was 92 amperes. The maximum open-circuit voltage coupled was 316 volts. The maximum short circuit current coupled onto a United Space Boosters, Inc. operational flight cable within the systems tunnel, induced by heater power cable transients only, was 2.7 amperes; the maximum open-circuit voltage coupled was 39 volts. All heater power cable induced coupling was due to simulated lightning discharges only, no heater operating power was applied during the test. The results showed that, for a worst-case lightning discharge, the heater power cable is responsible for a 3.9 decibel increase in voltage coupling to operational flight cables within the systems tunnel. Testing also showed that current and voltage levels coupled onto cables within the systems tunnel are partially dependant on the relative locations of the cables within the systems tunnel.
Reducing Magnetic Fields Around Power Cables
NASA Technical Reports Server (NTRS)
Sargent, Noel B.; Gitelman, Florida; Pongracz-Bartha, Edward; Spalding, John
1993-01-01
Four power conductors arranged symmetrically about fifth grounded conductor. Four current-carrying wires arranged symmetrically around central grounded wire that nominally carries no current. In comparison with other cable configurations, this one results in smaller magnetic fields around cable. Technique for use when size of wires in cable makes twisting impractical.
Wyman, Megan T.; Kavet, Robert
2017-01-01
Empirical evidence exists that some marine animals perceive and orient to local distortions in the earth’s main static geomagnetic field. The magnetic fields produced by undersea electric power cables that carry electricity from hydrokinetic energy sources to shore-based power stations may produce similar local distortions in the earth’s main field. Concerns exist that animals migrating along the continental shelves might orient to the magnetic field from the cables, and move either inshore or offshore away from their normal path. We have studied the effect of the Trans Bay Cable (TBC), an 85-km long, high voltage, direct current (DC) transmission line leading underwater from Pittsburg, CA to San Francisco, CA, on fishes migrating through the San Francisco Estuary. These included Chinook salmon smolts (Oncorhynchus tshawytscha) that migrate downstream through the San Francisco Estuary to the Pacific Ocean and adult green sturgeon (Acipenser medirostris), which migrate upstream from the ocean through the estuary to their spawning habitat in the upper Sacramento River and return to the ocean after spawning occurs. Based on a detailed gradiometer survey, we found that the distortions in the earth’s main field produced by bridges across the estuary were much greater than those from the Trans Bay Cable. The former anomalies exceeded the latter by an order of magnitude or more. Significant numbers of tagged Chinook salmon smolts migrated past bridges, which produced strong magnetic anomalies, to the Golden Gate Bridge, where they were recorded by dual arrays of acoustic tag-detecting monitors moored in lines across the mouth of the bay. In addition, adult green sturgeon successfully swam upstream and downstream through the estuary on the way to and from their spawning grounds. Hence, the large anomalies produced by the bridges do not appear to present a strong barrier to the natural seasonal movement patterns of salmonid smolts and adult green sturgeon. PMID:28575021
Klimley, A Peter; Wyman, Megan T; Kavet, Robert
2017-01-01
Empirical evidence exists that some marine animals perceive and orient to local distortions in the earth's main static geomagnetic field. The magnetic fields produced by undersea electric power cables that carry electricity from hydrokinetic energy sources to shore-based power stations may produce similar local distortions in the earth's main field. Concerns exist that animals migrating along the continental shelves might orient to the magnetic field from the cables, and move either inshore or offshore away from their normal path. We have studied the effect of the Trans Bay Cable (TBC), an 85-km long, high voltage, direct current (DC) transmission line leading underwater from Pittsburg, CA to San Francisco, CA, on fishes migrating through the San Francisco Estuary. These included Chinook salmon smolts (Oncorhynchus tshawytscha) that migrate downstream through the San Francisco Estuary to the Pacific Ocean and adult green sturgeon (Acipenser medirostris), which migrate upstream from the ocean through the estuary to their spawning habitat in the upper Sacramento River and return to the ocean after spawning occurs. Based on a detailed gradiometer survey, we found that the distortions in the earth's main field produced by bridges across the estuary were much greater than those from the Trans Bay Cable. The former anomalies exceeded the latter by an order of magnitude or more. Significant numbers of tagged Chinook salmon smolts migrated past bridges, which produced strong magnetic anomalies, to the Golden Gate Bridge, where they were recorded by dual arrays of acoustic tag-detecting monitors moored in lines across the mouth of the bay. In addition, adult green sturgeon successfully swam upstream and downstream through the estuary on the way to and from their spawning grounds. Hence, the large anomalies produced by the bridges do not appear to present a strong barrier to the natural seasonal movement patterns of salmonid smolts and adult green sturgeon.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Klimley, A. Peter; Wyman, Megan T.; Kavet, Robert
Empirical evidence exists that some marine animals perceive and orient to local distortions in the earth's main static geomagnetic field. The magnetic fields produced by undersea electric power cables that carry electricity from hydrokinetic energy sources to shore-based power stations may produce similar local distortions in the earth's main field. Concerns exist that animals migrating along the continental shelves might orient to the magnetic field from the cables, and move either inshore or offshore away from their normal path. We studied the effect of the Trans Bay Cable (TBC), an 85-km long, high voltage, direct current (DC) transmission line leadingmore » underwater from Pittsburg, CA to San Francisco, CA, on fishes migrating through the San Francisco Estuary. These included Chinook salmon smolts (Oncorhynchus tshawytscha) that migrate downstream through the San Francisco Estuary to the Pacific Ocean and adult green sturgeon (Acipenser medirostris), which migrate upstream from the ocean through the estuary to their spawning habitat in the upper Sacramento River and return to the ocean after spawning occurs. And based on a detailed gradiometer survey, we found that the distortions in the earth's main field produced by bridges across the estuary were much greater than those from the Trans Bay Cable. The former anomalies exceeded the latter by an order of magnitude or more. Significant numbers of tagged Chinook salmon smolts migrated past bridges, which produced strong magnetic anomalies, to the Golden Gate Bridge, where they were recorded by dual arrays of acoustic tag-detecting monitors moored in lines across the mouth of the bay. Additionally, adult green sturgeon successfully swam upstream and downstream through the estuary on the way to and from their spawning grounds. Hence, the large anomalies produced by the bridges do not appear to present a strong barrier to the natural seasonal movement patterns of salmonid smolts and adult green sturgeon.« less
Klimley, A. Peter; Wyman, Megan T.; Kavet, Robert; ...
2017-06-02
Empirical evidence exists that some marine animals perceive and orient to local distortions in the earth's main static geomagnetic field. The magnetic fields produced by undersea electric power cables that carry electricity from hydrokinetic energy sources to shore-based power stations may produce similar local distortions in the earth's main field. Concerns exist that animals migrating along the continental shelves might orient to the magnetic field from the cables, and move either inshore or offshore away from their normal path. We studied the effect of the Trans Bay Cable (TBC), an 85-km long, high voltage, direct current (DC) transmission line leadingmore » underwater from Pittsburg, CA to San Francisco, CA, on fishes migrating through the San Francisco Estuary. These included Chinook salmon smolts (Oncorhynchus tshawytscha) that migrate downstream through the San Francisco Estuary to the Pacific Ocean and adult green sturgeon (Acipenser medirostris), which migrate upstream from the ocean through the estuary to their spawning habitat in the upper Sacramento River and return to the ocean after spawning occurs. And based on a detailed gradiometer survey, we found that the distortions in the earth's main field produced by bridges across the estuary were much greater than those from the Trans Bay Cable. The former anomalies exceeded the latter by an order of magnitude or more. Significant numbers of tagged Chinook salmon smolts migrated past bridges, which produced strong magnetic anomalies, to the Golden Gate Bridge, where they were recorded by dual arrays of acoustic tag-detecting monitors moored in lines across the mouth of the bay. Additionally, adult green sturgeon successfully swam upstream and downstream through the estuary on the way to and from their spawning grounds. Hence, the large anomalies produced by the bridges do not appear to present a strong barrier to the natural seasonal movement patterns of salmonid smolts and adult green sturgeon.« less
NASA Astrophysics Data System (ADS)
Niu, Jie; Li, Jinliang; Zou, Dehua; Yang, Qi; Li, Xu; Yan, Yu; Li, Tang
2017-05-01
Non-blackout working of agricultural power supply network is significant to shorten the outage time, decrease the outage loss, and improve the supply reliability and safety. It is impossible to hang the wire rope first and then suspend the cable because of the poor bearing ability of the pole in agricultural power supply network. A kind of new cable arrangement way, its matching tools and the flexible cable that can bear the tension by itself are needed to be put forward and developed. It is necessary to calculate the electric field intensity of the flexible cable to verify that the electric field intensity meets the insulation demand. In this new design, the fiber layer is added into the flexible cable and its maximum tension force is measured to reach to 4000 N. Based on the features of live working in the agricultural power supply network, the new layout way of the cable is proposed; the matching tools and the new flexible cable that can bear the tension by itself are developed as well in this paper. All of the research achievements can give references for the live working of the agricultural power supply network.
NASA Astrophysics Data System (ADS)
Dobra, R.; Pasculescu, D.; Risteiu, M.; Buica, G.; Jevremović, V.
2017-06-01
This paper describe some possibilities to minimize voltages switching-off risks from the mining power networks, in case of insulated resistance faults by using a predictive diagnose method. The cables from the neutral insulated power networks (underground mining) are designed to provide a flexible electrical connection between portable or mobile equipment and a point of supply, including main feeder cable for continuous miners, pump cable, and power supply cable. An electronic protection for insulated resistance of mining power cables can be made using this predictive strategy. The main role of electronic relays for insulation resistance degradation of the electrical power cables, from neutral insulated power networks, is to provide a permanent measurement of the insulated resistance between phases and ground, in order to switch-off voltage when the resistance value is below a standard value. The automat system of protection is able to signalize the failure and the human operator will be early informed about the switch-off power and will have time to take proper measures to fix the failure. This logic for fast and automat switch-off voltage without aprioristic announcement is suitable for the electrical installations, realizing so a protection against fires and explosion. It is presented an algorithm and an anticipative relay for insulated resistance control from three-phase low voltage installations with insulated neutral connection.
30 CFR 75.1002 - Installation of electric equipment and conductors; permissibility.
Code of Federal Regulations, 2012 CFR
2012-07-01
... faces must be— (1) Shielded high-voltage cables supplying power to permissible longwall equipment; (2... intrinsically safe circuits; and (4) Cables and conductors supplying power to low- and medium-voltage permissible equipment. (5) Shielded high-voltage cables supplying power to permissible continuous mining...
30 CFR 75.1002 - Installation of electric equipment and conductors; permissibility.
Code of Federal Regulations, 2013 CFR
2013-07-01
... faces must be— (1) Shielded high-voltage cables supplying power to permissible longwall equipment; (2... intrinsically safe circuits; and (4) Cables and conductors supplying power to low- and medium-voltage permissible equipment. (5) Shielded high-voltage cables supplying power to permissible continuous mining...
30 CFR 75.1002 - Installation of electric equipment and conductors; permissibility.
Code of Federal Regulations, 2014 CFR
2014-07-01
... faces must be— (1) Shielded high-voltage cables supplying power to permissible longwall equipment; (2... intrinsically safe circuits; and (4) Cables and conductors supplying power to low- and medium-voltage permissible equipment. (5) Shielded high-voltage cables supplying power to permissible continuous mining...
Detection of High-impedance Arcing Faults in Radial Distribution DC Systems
NASA Technical Reports Server (NTRS)
Gonzalez, Marcelo C.; Button, Robert M.
2003-01-01
High voltage, low current arcing faults in DC power systems have been researched at the NASA Glenn Research Center in order to develop a method for detecting these 'hidden faults', in-situ, before damage to cables and components from localized heating can occur. A simple arc generator was built and high-speed and low-speed monitoring of the voltage and current waveforms, respectively, has shown that these high impedance faults produce a significant increase in high frequency content in the DC bus voltage and low frequency content in the DC system current. Based on these observations, an algorithm was developed using a high-speed data acquisition system that was able to accurately detect high impedance arcing events induced in a single-line system based on the frequency content of the DC bus voltage or the system current. Next, a multi-line, radial distribution system was researched to see if the arc location could be determined through the voltage information when multiple 'detectors' are present in the system. It was shown that a small, passive LC filter was sufficient to reliably isolate the fault to a single line in a multi-line distribution system. Of course, no modification is necessary if only the current information is used to locate the arc. However, data shows that it might be necessary to monitor both the system current and bus voltage to improve the chances of detecting and locating high impedance arcing faults
30 CFR 75.831 - Electrical work; troubleshooting and testing.
Code of Federal Regulations, 2014 CFR
2014-07-01
...) or (2): (1) If a trailing cable disconnecting switch is provided: (i) Open and ground the power... power receptacle. (b) Troubleshooting and testing the trailing cable. During troubleshooting and testing, the de-energized high-voltage cable may be disconnected from the power center only for that period of...
30 CFR 75.831 - Electrical work; troubleshooting and testing.
Code of Federal Regulations, 2012 CFR
2012-07-01
...) or (2): (1) If a trailing cable disconnecting switch is provided: (i) Open and ground the power... power receptacle. (b) Troubleshooting and testing the trailing cable. During troubleshooting and testing, the de-energized high-voltage cable may be disconnected from the power center only for that period of...
30 CFR 75.831 - Electrical work; troubleshooting and testing.
Code of Federal Regulations, 2013 CFR
2013-07-01
...) or (2): (1) If a trailing cable disconnecting switch is provided: (i) Open and ground the power... power receptacle. (b) Troubleshooting and testing the trailing cable. During troubleshooting and testing, the de-energized high-voltage cable may be disconnected from the power center only for that period of...
30 CFR 75.831 - Electrical work; troubleshooting and testing.
Code of Federal Regulations, 2011 CFR
2011-07-01
...) or (2): (1) If a trailing cable disconnecting switch is provided: (i) Open and ground the power... power receptacle. (b) Troubleshooting and testing the trailing cable. During troubleshooting and testing, the de-energized high-voltage cable may be disconnected from the power center only for that period of...
77 FR 35306 - Airworthiness Directives; Bell Helicopter Textron, Inc. Helicopters
Federal Register 2010, 2011, 2012, 2013, 2014
2012-06-13
... assemblies (power cable assemblies). This proposed AD is prompted by the determination that the power cable assembly connector (connector) can deteriorate, causing a short in the connector that may lead to a fire. This AD would require replacing the power cable assemblies and their associated parts, and performing...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nikiforov, E. P.
2009-07-15
Damage by lightning discharges to lightning arrester cables for 110-175 kV aerial transmission lines is analyzed using data from power systems on incidents with aerial transmission lines over a ten year operating period (1997-2006). It is found that failures of lightning arrester cables occur when a tensile force acts on a cable heated to the melting point by a lightning current. The lightning currents required to heat a cable to this extent are greater for larger cable cross sections. The probability that a lightning discharge will develop decreases as the amplitude of the lightning current increases, which greatly reduces themore » number of lightning discharges which damage TK-70 cables compared to TK-50 cables. In order to increase the reliability of lightning arrester cables for 110 kV aerial transmission lines, TK-70 cables should be used in place of TK-50 cables. The number of lightning discharges per year which damage lightning arrester cables is lowered when the density of aerial transmission lines is reduced within the territory of electrical power systems. An approximate relationship between these two parameters is obtained.« less
Effects on Freshwater Organisms of Magnetic Fields Associated with Hydrokinetic Turbines
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cada, Glenn F; Bevelhimer, Mark S; Riemer, Kristina P
2011-07-01
Underwater cables will be used to transmit electricity between turbines in an array (interturbine cables), between the array and a submerged step-up transformer (if part of the design), and from the transformer or array to shore. All types of electrical transmitting cables (as well as the generator itself) will emit EMF into the surrounding water. The electric current will induce magnetic fields in the immediate vicinity, which may affect the behavior or viability of animals. Because direct electrical field emissions can be prevented by shielding and armoring, we focused our studies on the magnetic fields that are unavoidably induced bymore » electric current moving through a generator or transmission cable. These initial experiments were carried out to evaluate whether a static magnetic field, such as would be produced by a direct current (DC) transmitting cable, would affect the behavior of common freshwater fish and invertebrates.« less
NASA Technical Reports Server (NTRS)
Cason, R. L.; Mcstay, J. J.; Heymann, A. P., Sr.
1979-01-01
Inexpensive system automatically indicates location of short-circuited section of power cable. Monitor does not require that cable be disconnected from its power source or that test signals be applied. Instead, ground-current sensors are installed in manholes or at other selected locations along cable run. When fault occurs, sensors transmit information about fault location to control center. Repair crew can be sent to location and cable can be returned to service with minimum of downtime.
A Marriage Proposal: Cable Television and Local Public Power.
ERIC Educational Resources Information Center
Schwartz, Louis; Woods, Robert A.
Two articles reprinted from "Public Power" discuss the present state of cable television (TV), its future prospects, and the opportunities offered municipal utilities by cable TV. The proposal is that local publicly-owned electric utilities meet the requirements of the Federal Communications Commission (FCC) for cable TV ownership and have the…
Development of Integrated Assessment System for Underground Power Cable Performance: A Case Study
NASA Astrophysics Data System (ADS)
Turan, Faiz Mohd; Johan, Kartina; Soliha Sahimi, Nur; Nor, Nik Hisyamudin Muhd
2017-08-01
The basic operation of any electrical machines that is catered to serve needs of civilization involves electrical power which is the main source to trigger the internal mechanism in the machines then transfer the power to other form of energy such as mechanical, light, sound and etc. The supplies of electrical does not happen just by providing the source itself, it has load carrying agent which in many cases, user would refer to it as cable. Specifically, it is the power cable which its ampacity depends significantly on the operation temperature and load stress on it. Apart from having to focus on providing improvement on improving efficiency on the source itself, power cable plays and important role because without it, current ranging from low to high could not be transmitted and hence a failure of the power system generally. Studies have conducted to discuss whether which factor contributes relatively more to the causes of power cable failure or breakdown. Such factors can be narrowed down to the three major causes which are over temperature, over voltage and stress caused by over current. Over current is one of the factor which is depends on the usage of the power system itself. The higher the usage of the power system, higher the chances of over current to take place. This will then produce load stress on the cable which eventually destroy the insulator of the cable and slowly reach the core of the cable. It is believed that an assessment method should be implemented in order to predict the performance and failure rate of the power cable and use this prediction as reference rather than just letting power failure to happen anytime unpredictable which cause huge inconvenience to users and industries. Not only do a method should be implemented, it should be as easy to be used and understood by large range of users and integrated by a graphical user interface to be used. Therefore, this research will further narrow down on the approaches to do so and the location of studies involve Company M which is an agriculture industries which has higher usage on their own underground power cable. Moreover, in the past history the company experienced electrical power failure and this studies and findings will definitely come in hand to provide them necessary help and benefits.
NASA Astrophysics Data System (ADS)
Liu, Hongfei; Pan, Gaofeng; Lin, Zhong; Liu, Cheng; Zhu, Wenbai; Nan, Rendong; Li, Chunsheng; Gao, Guanjun; Luo, Wenyong; Jin, Chengjin; Song, Jinyou
2017-11-01
The construction of FAST telescope was completed in Guizhou province of China in September 2016, and a kind of novel high-stability 48-core bendable and movable optical cable was developed and applied in analog data optical transmission system of FAST. Novel structure and selective material of this optical cable ensure high stability of optical power in the process of cables round-trip motion when telescope is tracking a radio source. The 105 times bend and stretch accelerated experiment for this optical cable was implemented, and real-time optical and RF signal power fluctuation were measured. The physical structure of optical cables after 105 times round-trip motion is in good condition; the real-time optical power attenuation fluctuation is smaller than 0.044 dB; the real-time RF power fluctuation is smaller than 0.12 dB. The optical cable developed in this letter meets the requirement of FAST and has been applied in FAST telescope.
High Voltage Power Transmission for Wind Energy
NASA Astrophysics Data System (ADS)
Kim, Young il
The high wind speeds and wide available area at sea have recently increased the interests on offshore wind farms in the U.S.A. As offshore wind farms become larger and are placed further from the shore, the power transmission to the onshore grid becomes a key feature. Power transmission of the offshore wind farm, in which good wind conditions and a larger installation area than an onshore site are available, requires the use of submarine cable systems. Therefore, an underground power cable system requires unique design and installation challenges not found in the overhead power cable environment. This paper presents analysis about the benefit and drawbacks of three different transmission solutions: HVAC, LCC/VSC HVDC in the grid connecting offshore wind farms and also analyzed the electrical characteristics of underground cables. In particular, loss of HV (High Voltage) subsea power of the transmission cables was evaluated by the Brakelmann's theory, taking into account the distributions of current and temperature.
Frequency domain reflectometry NDE for aging cables in nuclear power plants
NASA Astrophysics Data System (ADS)
Glass, S. W.; Jones, A. M.; Fifield, L. S.; Hartman, T. S.
2017-02-01
Degradation of the cable jacket, electrical insulation, and other cable components of installed cables within nuclear power plants (NPPs) is known to occur as a function of age, temperature, radiation, and other environmental factors. Although system tests verify cable function under normal loads, demonstration of some cable's ability to perform under exceptional loads associated with design-basis events is essential to assuring plant integrity. The cable's ability to perform safely over the initial 40-year planned and licensed life has generally been demonstrated and there have been very few age-related cable failures. With greater than 1000 km of power, control, instrumentation, and other cables typically found in an NPP, replacing all the cables would be a severe cost burden. Justification for life extension to 60 and 80 years requires a cable aging management program that includes condition monitoring to justify cable performance under normal operation as well as accident conditions. A variety of tests are available to assess various aspects of electrical and mechanical cable performance, but none are suitable for all cable configurations nor does any single test confirm all features of interest. One particularly promising test that is beginning to be used more and more by utilities is frequency domain reflectometry (FDR). FDR is a nondestructive electrical inspection technique used to detect and localize faults in power and communication system conductors along the length of a cable from a single connection point. FDR detects discontinuities in the electrical impedance that arise due to cable splices or similar changes along the path of the conductor pair. In addition, FDR has the potential to provide sensitivity to insulation degradation by detecting small changes in impedance between the cable conductors being examined. The technique is also sensitive to cable bends, the particular lay of the cable in tray, proximity to other cable, and other factors that bear consideration when interpreting the test results. This paper examines various influences on the FDR approach and compares results of three different instruments to assess accelerated aging damage among several NPP representative cables.
Small, Optically-Driven Power Source
NASA Technical Reports Server (NTRS)
Cockrum, Richard H.; Wang, Ke-Li J.
1988-01-01
Power transmitted along fiber-optic cables. Transmitted as infrared light along fiber-optic cable, converted to electricity to supply small electronic circuit. Power source and circuit remains electrically isolated from each other for safety or reduces electromagnetic interference. Array of diodes made by standard integrated-circuit techniques and packaged for mounting at end of fiber-optic cable.
Reliability and Characterization of High Voltage Power Capacitors
2014-03-01
Cable The HVPS cable is a specialized coaxial cable that utilizes a high voltage bayonet connector. The cable itself has a voltage rating in excess...the( LabVIEW(program( GPIB( CABLE ( HVPS( HVPS( COAXIAL ( CABLE ( BNC( COAXIAL ( CABLE ( BNC( COAXIAL ( CABLE ( CAPACITOR(‘C’(DATA( CAPACITOR(‘A’(DATA( Circuit...16 F. CABLES AND CONNECTORS ...................................................................16
Design and Development of a Single Channel RSNS Direction Finder
2009-03-01
CH2 12VDC 2.5A, and CH3 -12VDC 0.2A Cable 19 Pasternek Cable RG-306 Variable Attenuator 1 Telonic Altair Attenuation Model 8140S Demodulator Board...information is estimated to average 1 hour per response, including the time for reviewing instruction, searching existing data sources, gathering and...Reduction Project (0704-0188) Washington DC 20503. 1 . AGENCY USE ONLY (Leave blank) 2. REPORT DATE March 2009 3. REPORT TYPE AND DATES COVERED
NASA Astrophysics Data System (ADS)
Wang, Jing; Qi, Zhaohui; Wang, Gang
2017-10-01
The dynamic analysis of cable-pulley systems is investigated in this paper, where the time-varying length characteristic of the cable as well as the coupling motion between the cable and the pulleys are considered. The dynamic model for cable-pulley systems are presented based on the principle of virtual power. Firstly, the cubic spline interpolation is adopted for modeling the flexible cable elements and the virtual 1powers of tensile strain, inertia and gravity forces on the cable are formulated. Then, the coupled motions between the cable and the movable or fixed pulley are described by the input and output contact points, based on the no-slip assumption and the spatial description. The virtual powers of inertia, gravity and applied forces on the contact segment of the cable, the movable and fixed pulleys are formulated. In particular, the internal node degrees of freedom of spline cable elements are reduced, which results in that only the independent description parameters of the nodes connected to the pulleys are included in the final governing dynamic equations. At last, two cable-pulley lifting mechanisms are considered as demonstrative application examples where the vibration of the lifting process is investigated. The comparison with ADAMS models is given to prove the validity of the proposed method.
Properties of plastic tapes for cryogenic power cable insulation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Muller, A C
1978-01-01
A superconducting ac power transmission cable is under development at Brookhaven National Laboratory (BNL). This project was undertaken in 1972 in response to growing national power requirements. The goal of this program is to develop an underground power transmission system suitable for transferring bulk quantities of electricity over distances of 16 to 160 km. Both the capital investment and operating costs must be low enough to make the system attractive to the electric utilities. The superconducting cable shares the advantages with conventional underground cables of needing only a few feet of right-of-way width rather than the large tracts of increasinglymore » expensive land required for conventional aerial transmission. Recent cost analysis studies show that superconducting cables, although more expensive than aerial transmission, will probably be competitive with other methods of underground transmission at loads greater than 2000 MVA. Initial design studies showed that a flexible, forced-cooled cable offered the best combination of technical and economic features. A helium cooled cable with Nb/sub 3/Sn superconductor was chosen as the BNL design. The present goal of the BNL program is the construction of a 100 meter outdoor three-phase ac cable rated at 138 kV and 1000 MVA. The refrigerator and the 100 m-long dewar are already installed. Terminations and cables are under design, and it is planned to begin installation of the first single phase cable in 1979. If the results on this model show promise for eventual commercial use, cables of higher voltage and power rating will be developed. One fundamental phase of this project; the development of the required insulating materials, is described.« less
16,000-rpm Interior Permanent Magnet Reluctance Machine with Brushless Field Excitation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hsu, J.S.; Burress, T.A.; Lee, S.T.
2007-10-31
The reluctance interior permanent magnet (RIPM) motor is currently used by many leading auto manufacturers for hybrid vehicles. The power density for this type of motor is high compared with that of induction motors and switched reluctance motors. The primary drawback of the RIPM motor is the permanent magnet (PM) because during high-speed operation, the fixed PM produces a huge back electromotive force (emf) that must be reduced before the current will pass through the stator windings. This reduction in back-emf is accomplished with a significant direct-axis (d-axis) demagnetization current, which opposes the PM's flux to reduce the flux seenmore » by the stator wires. This may lower the power factor and efficiency of the motor and raise the requirement on the alternate current (ac) power supply; consequently, bigger inverter switching components, thicker motor winding conductors, and heavier cables are required. The direct current (dc) link capacitor is also affected when it must accommodate heavier harmonic currents. It is commonly agreed that, for synchronous machines, the power factor can be optimized by varying the field excitation to minimize the current. The field produced by the PM is fixed and cannot be adjusted. What can be adjusted is reactive current to the d-axis of the stator winding, which consumes reactive power but does not always help to improve the power factor. The objective of this project is to avoid the primary drawbacks of the RIPM motor by introducing brushless field excitation (BFE). This offers both high torque per ampere (A) per core length at low speed by using flux, which is enhanced by increasing current to a fixed excitation coil, and flux, which is weakened at high speed by reducing current to the excitation coil. If field weakening is used, the dc/dc boost converter used in a conventional RIPM motor may be eliminated to reduce system costs. However, BFE supports a drive system with a dc/dc boost converter, because it can further extend the constant power speed range of the drive system and adjust the field for power factor and efficiency gains. Lower core losses at low torque regions, especially at high speeds, are attained by reducing the field excitation. Safety and reliability are increased by weakening the field when a winding short-circuit fault occurs, preventing damage to the motor. For a high-speed motor operating at 16,000-revolutions per minute (rpm), mechanical stress is a challenge. Bridges that link the rotor punching segments together must be thickened for mechanical integrity; consequently, increased rotor flux leakage significantly lowers motor performance. This barrier can be overcome by BFE to ensure sufficient rotor flux when needed.« less
Assessment of 69 kV Underground Cable Thermal Ratings using Distributed Temperature Sensing
NASA Astrophysics Data System (ADS)
Stowers, Travis
Underground transmission cables in power systems are less likely to experience electrical faults, however, resulting outage times are much greater in the event that a failure does occur. Unlike overhead lines, underground cables are not self-healing from flashover events. The faulted section must be located and repaired before the line can be put back into service. Since this will often require excavation of the underground duct bank, the procedure to repair the faulted section is both costly and time consuming. These added complications are the prime motivators for developing accurate and reliable ratings for underground cable circuits. This work will review the methods by which power ratings, or ampacity, for underground cables are determined and then evaluate those ratings by making comparison with measured data taken from an underground 69 kV cable, which is part of the Salt River Project (SRP) power subtransmission system. The process of acquiring, installing, and commissioning the temperature monitoring system is covered in detail as well. The collected data are also used to evaluate typical assumptions made when determining underground cable ratings such as cable hot-spot location and ambient temperatures. Analysis results show that the commonly made assumption that the deepest portion of an underground power cable installation will be the hot-spot location does not always hold true. It is shown that distributed cable temperature measurements can be used to locate the proper line segment to be used for cable ampacity calculations.
Assessment of NDE for key indicators of aging cables in nuclear power plants - Interim status
NASA Astrophysics Data System (ADS)
Glass, S. W.; Ramuhalli, P.; Fifield, L. S.; Prowant, M. S.; Dib, G.; Tedeschi, J. R.; Suter, J. D.; Jones, A. M.; Good, M. S.; Pardini, A. F.; Hartman, T. S.
2016-02-01
Degradation of the cable jacket, electrical insulation, and other cable components of installed cables within nuclear power plants (NPPs) is known to occur as a function of age, temperature, radiation, and other environmental factors. System tests verify cable function under normal loads; however, the concern is over cable performance under exceptional loads associated with design-basis events (DBEs). The cable's ability to perform safely over the initial 40-year planned and licensed life has generally been demonstrated and there have been very few age-related cable failures. With greater than 1000 km of power, control, instrumentation, and other cables typically found in an NPP, replacing all the cables would be a severe cost burden. Justification for life extension to 60 and 80 years requires a cable aging management program to justify cable performance under normal operation as well as accident conditions. Currently the gold standard for determining cable insulation degradation is the elongation-at-break (EAB). This, however, is an ex-situ measurement and requires removal of a sample for laboratory investigation. A reliable nondestructive examination (NDE) in-situ approach is desirable to objectively determine the suitability of the cable for service. A variety of tests are available to assess various aspects of electrical and mechanical cable performance, but none of these tests are suitable for all cable configurations nor does any single test confirm all features of interest. Nevertheless, the complete collection of test possibilities offers a powerful range of tools to assure the integrity of critical cables. Licensees and regulators have settled on a practical program to justify continued operation based on condition monitoring of a lead sample set of cables where test data is tracked in a database and the required test data are continually adjusted based on plant and fleet-wide experience. As part of the Light Water Reactor Sustainability program sponsored by the U.S. Nuclear Regulatory Commission, the U.S. Department of Energy, and industry (represented by the Electric Power Research Institute), an assessment of cable NDE methods was commissioned. Technologies include both bulk electrical measurements (Tan δ, time domain reflectometry, frequency domain reflectometry (FDR), partial discharge, and other techniques) and local insulation measurement (indenter, dynamic mechanical analysis interdigital capacitance, infrared spectral measurement, etc.). This aging cable NDE program update reviews the full range of techniques but focuses on the most interesting test approaches that have a chance to be deployed in-situ, particularly including Tan δ, FDR, and ultrasound methods that have been reviewed most completely in this progress period.
Operating experience with the southwire 30-meter high-temperature superconducting power cable
NASA Astrophysics Data System (ADS)
Stovall, J. P.; Lue, J. W.; Demko, J. A.; Fisher, P. W.; Gouge, M. J.; Hawsey, R. A.; Armstrong, J. W.; Hughey, R. L.; Lindsay, D. T.; Roden, M. L.; Sinha, U. K.; Tolbert, J. C.
2002-05-01
Southwire Company is operating a high-temperature superconducting (HTS) cable system at its corporate headquarters. The 30-m long, 3-phase cable system is powering three Southwire manufacturing plants and is rated at 12.4-kV, 1250-A, 60-Hz. Cooling is provided by a pressurized liquid nitrogen system operating at 70-80 K. The cables were energized on January 5, 2000 for on-line testing and operation and in April 2000 were placed into extended service. As of June 1, 2001, the HTS cables have provided 100% of the customer load for 8000 hours. The cryogenic system has been in continuous operation since November 1999. The HTS cable system has not been the cause of any power outages to the average 20 MW industrial load served by the cable. The cable has been exposed to short-circuit currents caused by load-side faults without damage. Based upon field measurements described herein, the cable critical current-a key performance parameter-remains the same and has not been affected by the hours of real-world operation, further proving the viability of this promising technology.
Internet of "printed" Things: low-cost fabrication of autonomous sensing nodes by inkjet printing
NASA Astrophysics Data System (ADS)
Kawahara, Yoshihiro
2014-11-01
"What if electronics devices are printed using an inkjet printer even at home?" "What if those devices no longer need a battery?" I will introduce two enabling technologies for the Internet of Things concept. 1. Instant Inkjet Circuits: A low cost, fast and accessible technology to support the rapid prototyping of electronic devices. We demonstrated that "sintering-free" silver nano particle ink with a commodity inkjet printer can be used to fabricate printed circuit board and high-frequency applications such as antennas and sensors. The technology is now commercialized by AgIC, Inc. 2. Wireless Power: Although large amounts of data can be exchanged over a wireless communication link, mobile devices are still tethered by power cables. We are trying to solve this problem by two different approaches: energy harvesting. A simple circuitry comprised of diodes and capacitor can convert ambient radio signals into DC current. Our research revealed the signals from TV tower located 6.5km apart could be used to feed 100 microwatts to power microcontrollers.
Environmental testing and laser transmission results for ruggedized high power IR fiber cables
NASA Astrophysics Data System (ADS)
Busse, Lynda; Kung, Frederic; Florea, Catalin; Shaw, Brandon; Aggarwal, Ishwar; Sanghera, Jas
2013-03-01
We present successful results of high mid-IR laser power transmission as well as MIL-SPEC environmental testing (thermal cycling and vibration testing) of ruggedized, IR-transmitting chalcogenide glass fiber cables. The cables tested included chalcogenide fiber cables with endfaces imprinted with anti-reflective "moth eye" surfaces, whereby the reflection loss is reduced from about 17% per end to less than 3%. The cables with these moth eye surfaces also show excellent laser damage resistance.
Flat conductor cable commercialization project
NASA Technical Reports Server (NTRS)
Hogarth, P.; Wadsworth, E.
1977-01-01
An undercarpet flat conductor cable and a baseboard flat conductor cable system were studied for commercialization. The undercarpet system is designed for use in office and commercial buildings. It employs a flat power cable, protected by a grounded metal shield, that terminates in receptacles mounted on the floor. It is designed to interface with a flat conductor cable telephone system. The baseboard system consists of a flat power cable mounted in a plastic raceway; both the raceway and the receptacles are mounted on the surface of the baseboard. It is designed primarily for use in residential buildings, particularly for renovation and concrete and masonry construction.
Transient analysis for alternating over-current characteristics of HTSC power transmission cable
NASA Astrophysics Data System (ADS)
Lim, S. H.; Hwang, S. D.
2006-10-01
In this paper, the transient analysis for the alternating over-current distribution in case that the over-current was applied for a high-TC superconducting (HTSC) power transmission cable was performed. The transient analysis for the alternating over-current characteristics of HTSC power transmission cable with multi-layer is required to estimate the redistribution of the over-current between its conducting layers and to protect the cable system from the over-current in case that the quench in one or two layers of the HTSC power cable happens. For its transient analysis, the resistance generation of the conducting layers for the alternating over-current was reflected on its equivalent circuit, based on the resistance equation obtained by applying discrete Fourier transform (DFT) for the voltage and the current waveforms of the HTSC tape, which comprises each layer of the HTSC power transmission cable. It was confirmed through the numerical analysis on its equivalent circuit that after the current redistribution from the outermost layer into the inner layers first happened, the fast current redistribution between the inner layers developed as the amplitude of the alternating over-current increased.
Thermal Insulation Performance of Flexible Piping for Use in HTS Power Cables
NASA Technical Reports Server (NTRS)
Fesmire, James E.; Augustynowicz, S. D.; Demko, J. A.; Thompson, Karen (Technical Monitor)
2001-01-01
High-temperature superconducting (HTS) cables that typically operate at temperatures below 80 K are being developed for power transmission. The practical application of HTS power cables will require the use of flexible piping to contain the cable and the liquid nitrogen coolant. A study of thermal performance of multilayer insulation (MLI) was conducted in geometries representing both rigid and flexible piping. This experimental study performed at the Cryogenics Test Laboratory of NASA Kennedy Space Center provides a framework for the development of cost-effective, efficient thermal insulation systems that will support these long-distance flexible lines containing HTS power cables. The overall thermal performance of the insulation system for a rigid configuration and for a flexible configuration, simulating a flexible HTS power cable, was determined by the steady-state liquid nitrogen boiloff method under the full range of vacuum levels. Two different cylindrically rolled material systems were tested: a standard MLI and a layered composite insulation (LCI). Comparisons of ideal MLI, MLI on rigid piping, and MLI between flexible piping are presented.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Trailing cables supplying power to low-voltage mobile equipment; ground wires and ground check wires. 77.906 Section 77.906 Mineral Resources MINE... wires and ground check wires. On and after September 30, 1971, all trailing cables supplying power to...
Code of Federal Regulations, 2010 CFR
2010-07-01
... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Trailing cables supplying power to low-voltage mobile equipment; ground wires and ground check wires. 77.906 Section 77.906 Mineral Resources MINE... wires and ground check wires. On and after September 30, 1971, all trailing cables supplying power to...
DC to DC power converters and methods of controlling the same
Steigerwald, Robert Louis; Elasser, Ahmed; Sabate, Juan Antonio; Todorovic, Maja Harfman; Agamy, Mohammed
2012-12-11
A power generation system configured to provide direct current (DC) power to a DC link is described. The system includes a first power generation unit configured to output DC power. The system also includes a first DC to DC converter comprising an input section and an output section. The output section of the first DC to DC converter is coupled in series with the first power generation unit. The first DC to DC converter is configured to process a first portion of the DC power output by the first power generation unit and to provide an unprocessed second portion of the DC power output of the first power generation unit to the output section.
Development of a Digital Tracking Array with Single- Channel RSNS and Monopulse Digital Beamforming
2010-12-01
Watt CH1 5.05 VDC 4 A, CH2 12 VDC 2.5 A, and CH3 12 VDC 0.2 A Cable 19 Pasternek Cable RG-306 Variable Attenuator 1 Telonic Altair Attenuation Model...for this collection of information is estimated to average 1 hour per response, including the time for reviewing instruction, searching existing data...Management and Budget, Paperwork Reduction Project (0704-0188) Washington DC 20503. 1 . AGENCY USE ONLY (Leave blank) 2. REPORT DATE December 2010 3
NASA Astrophysics Data System (ADS)
Jaros, Jakub; Liner, Andrej; Papes, Martin; Vasinek, Vladimir; Mach, Veleslav; Hruby, David; Kajnar, Tomas; Perecar, Frantisek
2015-01-01
Nowadays, the power cables are manufactured to fulfill the following condition - the highest allowable temperature of the cable during normal operation and the maximum allowable temperature at short circuit conditions cannot exceed the condition of the maximum allowable internal temperature. The distribution of the electric current through the conductor leads to the increase of the amplitude of electrons in the crystal lattice of the cables material. The consequence of this phenomenon is the increase of friction and the increase of collisions between particles inside the material, which causes the temperature increase of the carrying elements. The temperature increase is unwanted phenomena, because it is causing losses. In extreme cases, the long-term overload leads to the cable damaging or fire. This paper deals with the temperature distribution measurement inside the power cables using distributed temperature system. With cooperation with Kabex company, the tube containing optical fibers was installed into the center of power cables. These fibers, except telecommunications purposes, can be also used as sensors in measurements carrying out with distributed temperature system. These systems use the optical fiber as a sensor and allow the continual measurement of the temperature along the whole cable in real time with spatial resolution 1 m. DTS systems are successfully deployed in temperature measurement applications in industry areas yet. These areas include construction, drainage, hot water etc. Their advantages are low cost, resistance to electromagnetic radiation and the possibility of real time monitoring at the distance of 8 km. The location of the optical fiber in the center of the power cable allows the measurement of internal distribution of the temperature during overloading the cable. This measurement method can be also used for prediction of short-circuit and its exact location.
NASA Astrophysics Data System (ADS)
Lohmeyer, Whitney; Carlton, Ashley; Wong, Frankie; Bodeau, Michael; Kennedy, Andrew; Cahoy, Kerri
2015-05-01
The key components in communications satellite payloads are the high-power amplifiers that amplify the received signal so that it can be accurately transmitted to the intended end user. In this study, we examine 26 amplifier anomalies and quantify the high-energy electron environment for periods of time prior to the anomalies. Building on the work of Lohmeyer and Cahoy (2013), we find that anomalies occur at a rate higher than just by chance when the >2 MeV electron fluence accumulated over 14 and 21 days is elevated. To try to understand "why," we model the amplifier subsystem to assess whether the dielectric material in the radio frequency (RF) coaxial cables, which are the most exposed part of the system, is liable to experience electrical breakdown due to internal charging. We find that the accumulated electric field over the 14 and 21 days leading up to the anomalies is high enough to cause the dielectric material in the coax to breakdown. We also find that the accumulated voltages reached are high enough to compromise components in the amplifier system, for example, the direct current (DC) blocking capacitor. An electron beam test using a representative coaxial cable terminated in a blocking capacitor showed that discharges could occur with peak voltages and energies sufficient to damage active RF semiconductor devices.
LONG TERM OPERATION ISSUES FOR ELECTRICAL CABLE SYSTEMS IN NUCLEAR POWER PLANTS
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fifield, Dr Leonard S; Duckworth, Robert C; Glass III, Dr. Samuel W.
Nuclear power plants contain hundreds of kilometers of electrical cables including cables used for power, for instrumentation, and for control. It is essential that safety-related cable systems continue to perform following a design-basis event. Wholesale replacement of electrical cables in existing plants facing licensing period renewal is both impractical and cost-prohibitive. It is therefore important to understand the long term aging of cable materials to have confidence that aged cables will perform when needed. It is equally important in support of cable aging management to develop methods to evaluate the health of installed cables and inform selective cable replacement decisions.more » The most common insulation materials for electrical cables in nuclear power plants are cross-linked polyethylene and ethylene-propylene rubber. The mechanical properties of these materials degrade over time in the presence of environmental stresses including heat, gamma irradiation, and moisture. Mechanical degradation of cable insulation beyond a certain threshold is unacceptable because it can lead to insulation cracking, exposure of energized conductors, arcing and burning or loss of the ability of the cable system to function during a design-basis accident. While thermal-, radiation-, and moisture-related degradation of polymer insulation materials has been extensively studied over the last few decades, questions remain regarding the long-term performance of cable materials in nuclear plant-specific environments. Identified knowledge gaps include an understanding of the temperature-dependence of activation energies for thermal damage and an understanding of the synergistic effects of radiation and thermal stress on polymer degradation. Many of the outstanding questions in the aging behavior of cable materials relate to the necessity of predicting long-term field degradation using accelerated aging results from the laboratory. Materials degrade faster under more extreme conditions, but extension of behavior to long term degradation under more mild conditions, such as those experienced by most installed cables in nuclear power plants, is complicated by the fact that different degradation mechanisms may be involved in extreme and mild scenarios. The discrepancy in predicted results from short term, more extreme exposure and actual results from longer term, more mild exposures can be counter intuitive. For instance, due to the attenuation of oxidation penetration in material samples rapidly aged through exposure to high temperatures, the bulk of the samples may be artificially protected from thermal aging. In another example, simultaneous exposure of cable insulation material to heat and radiation may actually lead to less damage at higher temperatures than may be observed at lower temperatures. The Light Water Reactor Sustainability program of the United States (US) Department of Energy Office (DOE) of Nuclear Energy is funding research to increase the predictive understanding of electrical cable material aging and degradation in existing nuclear power plants in support of continued safe operation of plants beyond their initial license periods. This research includes the evaluation and development of methods to assess installed cable condition.« less
Space Station Freedom primary power wiring requirements
NASA Technical Reports Server (NTRS)
Hill, Thomas J.
1994-01-01
The Space Station Freedom (SSF) Program requirements are a 30 year reliable service life in low Earth orbit in hard vacuum or pressurized module service without detrimental degradation. Specific requirements are outlined in this presentation for SSF primary power and cable insulation. The primary power cable status and the WP-4 planned cable test program are also reviewed along with Rocketdyne-WP04 prime insulation candidates.
NASA Astrophysics Data System (ADS)
Hatwar, R.; Kvitkovic, J.; Herman, C.; Pamidi, S.
2015-12-01
High Temperature Superconducting (HTS) materials have been demonstrated to be suitable for applications in shielding of both DC and AC magnetic fields. Magnetic shielding is required for protecting sensitive instrumentation from external magnetic fields and for preventing the stray magnetic fields produced by high power density equipment from affecting neighbouring devices. HTS shields have high current densities at relatively high operating temperatures (40-77 K) and can be easily fabricated using commercial HTS conductor. High current densities in HTS materials allow design and fabrication of magnetic shields that are lighter and can be incorporated into the body and skin of high power density devices. HTS shields are particularly attractive for HTS devices because a single cryogenic system can be used for cooling the device and the associated shield. Typical power devices need penetrations for power and signal cabling and the penetrations create discontinuities in HTS shields. Hence it is important to assess the effect of the necessary discontinuities on the efficacy of the shields and the design modifications necessary to accommodate the penetrations.
The cable catapult - Putting it there and keeping it there
NASA Technical Reports Server (NTRS)
Forward, Robert L.; Conley, Buford R.; Stanek, Clay; Ramsey, William
1992-01-01
The cable catapult is the previously proposed method of using long space tethers for high speed interplanetary transport. A long conductive multistrand cable would be connected to a power supply and pointed in the desired direction. A linear motor would pull itself along the powered cable strands and launch a payload capsule toward a distant planet, where it would be caught and decelerated by another cable catapult positioned there. In this paper it is shown how cable catapults can be used to transport themselves to a distant planet and keep themselves in position near the planet despite the tendency of the payload capsule momentum transfer to push them apart.
The cable catapult - Putting it there and keeping it there
NASA Astrophysics Data System (ADS)
Forward, Robert L.; Conley, Buford R.; Stanek, Clay; Ramsey, William
1992-07-01
The cable catapult is the previously proposed method of using long space tethers for high speed interplanetary transport. A long conductive multistrand cable would be connected to a power supply and pointed in the desired direction. A linear motor would pull itself along the powered cable strands and launch a payload capsule toward a distant planet, where it would be caught and decelerated by another cable catapult positioned there. In this paper it is shown how cable catapults can be used to transport themselves to a distant planet and keep themselves in position near the planet despite the tendency of the payload capsule momentum transfer to push them apart.
46 CFR 177.202 - Plans and information required.
Code of Federal Regulations, 2010 CFR
2010-10-01
... materials; (iv) Type and size of generators and prime movers; (v) Type and size of generator cables, bus-tie... 7102, Washington, DC 20593-7102. Three copies of all documents are required to be submitted for Marine...
Electronics and Software Engineer for Robotics Project Intern
NASA Technical Reports Server (NTRS)
Teijeiro, Antonio
2017-01-01
I was assigned to mentor high school students for the 2017 First Robotics Competition. Using a team based approach, I worked with the students to program the robot and applied my electrical background to build the robot from start to finish. I worked with students who had an interest in electrical engineering to teach them about voltage, current, pulse width modulation, solenoids, electromagnets, relays, DC motors, DC motor controllers, crimping and soldering electrical components, Java programming, and robotic simulation. For the simulation, we worked together to generate graphics files, write simulator description format code, operate Linux, and operate SOLIDWORKS. Upon completion of the FRC season, I transitioned over to providing full time support for the LCS hardware team. During this phase of my internship I helped my co-intern write test steps for two networking hardware DVTs , as well as run cables and update cable running lists.
Fiber optic sensors for nuclear power plant applications
NASA Astrophysics Data System (ADS)
Kasinathan, Murugesan; Sosamma, Samuel; BabuRao, Chelamchala; Murali, Nagarajan; Jayakumar, Tammana
2012-05-01
Studies have been carried out for application of Raman Distributed Temperature Sensor (RDTS) in Nuclear Power Plants (NPP). The high temperature monitoring in sodium circuits of Fast Breeder Reactor (FBR) is important. It is demonstrated that RDTS can be usefully employed in monitoring sodium circuits and in tracking the percolating sodium in the surrounding insulation in case of any leak. Aluminum Conductor Steel Reinforced (ACSR) cable is commonly used as overhead power transmission cable in power grid. The suitability of RDTS for detecting defects in ACSR overhead power cable, is also demonstrated.
Noise propagation effects in power supply distribution systems for high-energy physics experiments
NASA Astrophysics Data System (ADS)
Arteche, F.; Rivetta, C.; Iglesias, M.; Echeverria, I.; Pradas, A.; Arcega, F. J.
2017-12-01
High-energy physics experiments are supplied by thousands of power supply units placed in distant areas from the front-end electronics. The power supply units and the front-end electronics are connected through long power cables that propagate the output noise from the power supplies to the detector. This paper addresses the effect of long cables on the noise propagation and the impact that those cables have on the conducted emission levels required for the power supplies and the selection of EMI filters for the front-end electronic low-voltage input. This analysis is part of the electromagnetic compatibility based design focused on functional safety to define the type of cable, shield connections, EMI filters and power supply specifications required to ensure the successful integration of the detector and, specifically, to achieve the designed performance of the front-end electronics.
Noise propagation effects in power supply distribution systems for high-energy physics experiments
Arteche, F.; Rivetta, C.; Iglesias, M.; ...
2017-12-05
High-energy physics experiments are supplied by thousands of power supply units placed in distant areas from the front-end electronics. The power supply units and the front-end electronics are connected through long power cables that propagate the output noise from the power supplies to the detector. Here, this paper addresses the effect of long cables on the noise propagation and the impact that those cables have on the conducted emission levels required for the power supplies and the selection of EMI filters for the front-end electronic low-voltage input. Lastly, this analysis is part of the electromagnetic compatibility based design focused onmore » functional safety to define the type of cable, shield connections, EMI filters and power supply specifications required to ensure the successful integration of the detector and, specifically, to achieve the designed performance of the front-end electronics.« less
Noise propagation effects in power supply distribution systems for high-energy physics experiments
DOE Office of Scientific and Technical Information (OSTI.GOV)
Arteche, F.; Rivetta, C.; Iglesias, M.
High-energy physics experiments are supplied by thousands of power supply units placed in distant areas from the front-end electronics. The power supply units and the front-end electronics are connected through long power cables that propagate the output noise from the power supplies to the detector. Here, this paper addresses the effect of long cables on the noise propagation and the impact that those cables have on the conducted emission levels required for the power supplies and the selection of EMI filters for the front-end electronic low-voltage input. Lastly, this analysis is part of the electromagnetic compatibility based design focused onmore » functional safety to define the type of cable, shield connections, EMI filters and power supply specifications required to ensure the successful integration of the detector and, specifically, to achieve the designed performance of the front-end electronics.« less
Noise propagation issues in Belle II pixel detector power cable
NASA Astrophysics Data System (ADS)
Iglesias, M.; Arteche, F.; Echeverria, I.; Pradas, A.; Rivetta, C.; Moser, H.-G.; Kiesling, C.; Rummel, S.; Arcega, F. J.
2018-04-01
The vertex detector used in the upgrade of High-Energy physics experiment Belle II includes DEPFET pixel detector (PXD) technology. In this complex topology the power supply units and the front-end electronics are connected through a PXD power cable bundle which may propagate the output noise from the power supplies to the vertex area. This paper presents a study of the propagation of noise caused by power converters in the PXD cable bundle based on Multi-conductor Transmission Line (MTL) theory. The work exposes the effect of the complex cable topology and shield connections on the noise propagation, which has an impact on the requirements of the power supplies. This analysis is part of the electromagnetic compatibility based design focused on functional safety to define the shield connections and power supply specifications required to ensure the successful integration of the detector and, specifically, to achieve the designed performance of the front-end electronics.
Code of Federal Regulations, 2010 CFR
2010-10-01
... requirements: (a) A shore power connection box or receptacle and a cable connecting this box or receptacle to... power cable must be provided with a disconnect means located on or near the main distribution panel...
77 FR 34876 - Airworthiness Directives; The Boeing Company
Federal Register 2010, 2011, 2012, 2013, 2014
2012-06-12
... (a flammable fluid leakage zone) or heat damage to the APU power feeder cable, insulation blankets... heat damage to the APU power feeder cable, insulation blankets, or pressure bulkhead. Relevant Service... feeder cable and heat damage of the insulation blanket adjacent to the clamp, a detailed inspection for...
Elastic guided wave propagation in electrical cables.
Mateo, Carlos; Talavera, Juan A; Muñoz, Antonio
2007-07-01
This article analyzes the propagation modes of ultrasound waves inside an electrical cable in order to assess its behavior as an acoustic transmission channel. A theoretical model for propagation of elastic waves in electric power cables is presented. The power cables are represented as viscoelastic-layered cylindrical structures with a copper core and a dielectric cover. The model equations then have been applied and numerically resolved for this and other known structures such as solid and hollow cylinders. The results are compared with available data from other models. Several experimental measures were carried out and were compared with results from the numerical simulations. Experimental and simulated results showed a significant difference between elastic wave attenuation inside standard versus bare, low-voltage power cables.
Distributed condition monitoring techniques of optical fiber composite power cable in smart grid
NASA Astrophysics Data System (ADS)
Sun, Zhihui; Liu, Yuan; Wang, Chang; Liu, Tongyu
2011-11-01
Optical fiber composite power cable such as optical phase conductor (OPPC) is significant for the development of smart grid. This paper discusses the distributed cable condition monitoring techniques of the OPPC, which adopts embedded single-mode fiber as the sensing medium. By applying optical time domain reflection and laser Raman scattering, high-resolution spatial positioning and high-precision distributed temperature measurement is executed. And the OPPC cable condition parameters including temperature and its location, current carrying capacity, and location of fracture and loss can be monitored online. OPPC cable distributed condition monitoring experimental system is set up, and the main parts including pulsed fiber laser, weak Raman signal reception, high speed acquisition and cumulative average processing, temperature demodulation and current carrying capacity analysis are introduced. The distributed cable condition monitoring techniques of the OPPC is significant for power transmission management and security.
Improving Legacy Aircraft Systems Through Condition-Based Maintenance: An H-60 Case Study
2014-09-01
level functions. These decompositions are equivalent to a detailed design effort in systems engineering. NAMPSOPs have a common architectural structure...Assembly Power Available Spindle Cables No.1 Engine Load Demand Spindle Control Cables Engine Pneumatic Starters Auxiliary Power Unit IRCM FLIR Mission...Analysis Fuel System Main Rotor Head Main Module Main Gear Box Radiator Engine Output Shaft Auxiliary Power Unit Flight Control Cables Tail Landing
Agamy, Mohammed; Elasser, Ahmed; Sabate, Juan Antonio; Galbraith, Anthony William; Harfman Todorovic, Maja
2014-09-09
A distributed photovoltaic (PV) power plant includes a plurality of distributed dc-dc converters. The dc-dc converters are configured to switch in coordination with one another such that at least one dc-dc converter transfers power to a common dc-bus based upon the total system power available from one or more corresponding strings of PV modules. Due to the coordinated switching of the dc-dc converters, each dc-dc converter transferring power to the common dc-bus continues to operate within its optimal efficiency range as well as to optimize the maximum power point tracking in order to increase the energy yield of the PV power plant.
Potential Impact of Submarine Power Cables on Crab Harvest
NASA Astrophysics Data System (ADS)
Bull, A. S.; Nishimoto, M.
2016-02-01
Offshore renewable energy installations convert wave or wind energy to electricity and transfer the power to shore through transmission cables laid on or buried beneath the seafloor. West coast commercial fishermen, who harvest the highly prized Dungeness crab (Metacarcinus magister) and the rock crab (Cancer spp.), are concerned that the interface of crabs and electromagnetic fields (EMF) from these cables will present an electrified fence on the seafloor that their target resource will not cross. Combined with the assistance of professional fishermen, submarine transmission cables that electrify island communities and offshore oil platforms in the eastern Pacific provide an opportunity to test the harvest of crab species across power transmission cables. In situ field techniques give commercial crab species a choice to decide if they will cross fully energized, EMF emitting, power transmission cables, in response to baited traps. Each independent trial is either one of two possible responses: the crab crosses the cable to enter a trap (1) or the crab does not cross the cable to enter a trap (0). Conditions vary among sample units by the following categorical, fixed factors (i.e., covariates) of cable structure (buried or unburied); direction of cable from crab position (west or east, north or south); time and season. A generalized linear model is fit to the data to determine whether any of these factors affect the probability of crabs crossing an energized cable to enter baited traps. Additionally, the experimental design, aside from the number of runs (set of sample trials) and the dates of the runs, is the same in the Santa Barbara Channel for rock crab and Puget Sound for Dungeness crab, and allows us to compare the capture rates of the two species in the two areas. We present preliminary results from field testing in 2015.
Technical feasibility of an ROV with on-board power
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sayer, P.; Bo, L.
1994-12-31
An ROI`s electric power, control and communication signals are supplied from a surface ship or platform through an umbilical cable. Though cable design has evolved steadily, there are still severe limitations such as heavy weight and cost. It is well known that the drag imposed by the cable limits the operational range of the ROV in deep water. On the other hand, a cable-free AUV presents problems in control, communication and transmission of data. Therefore, an ROV with on-board and small-diameter cable could offer both a large operating range (footprint) and real-time control. This paper considers the feasibility of suchmore » an ROV with on-board power, namely a Self-Powered ROV (SPROV). The selection of possible power sources is first discussed before comparing the operational performance of an SPROV against a conventional ROV. It is demonstrated how an SPROV with a 5mm diameter tether offers a promising way forward, with on-board power of up to 40 kW over 24 hours. In water depths greater than 50m the reduced drag of the SPROV tether is very advantageous.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Glass, Samuel W.; Fifield, Leonard S.; Jones, Anthony M.
Cable insulation polymers are among the more susceptible materials to age-related degradation within a nuclear power plant. This is recognized by both regulators and utilities, so all plants have developed cable aging management programs to detect damage before critical component failure in compliance with regulatory guidelines. Although a wide range of tools are available to evaluate cables and cable systems, cable aging management programs vary in how condition monitoring and NDE is conducted as utilities search for the most reliable and cost-effective ways to assess cable system condition. Frequency domain reflectometry (FDR) is emerging as one valuable tool to locatemore » and assess damaged portions of a cable system with minimal cost and only requires access in most cases to one of the cable terminal ends. This work examines a physics-based model of a cable system and relates it to FDR measurements for a better understanding of specific damage influences on defect detectability.« less
29 CFR 1918.64 - Powered conveyors.
Code of Federal Regulations, 2010 CFR
2010-07-01
... the brakes cannot be released until power is applied and the brakes are automatically engaged if the... provided for use in an emergency. Whenever the operation of any power conveyor requires personnel to work... the trimmer. (e) Grain trimmer power cable. Power cables between the deck control box and the grain...
Interstrand contact resistances of Bi-2212 Rutherford cables for SMES
NASA Astrophysics Data System (ADS)
Kawagoe, A.; Kawabata, Y.; Sumiyoshi, F.; Nagaya, S.; Hirano, N.
2006-10-01
Interstrand contact resistances of Bi-2212 Rutherford cables for SMES coils were evaluated from a comparison between measured data and 2D-FEM analyses on interstrand coupling losses in these cables. The cables were composed of 30 non-twisted Bi-2212 strands with a diameter of 0.81 mm and a cable twist pitch of 90 mm. Three samples were measured; one of them had NiCr cores and the others had no cores. One of the latter two samples repeatedly experienced bending. The interstrand coupling losses were measured in liquid helium for the straight samples under transverse ac ripple magnetic fields superposed on dc bias magnetic fields. The transverse magnetic field was applied to the samples in directions both perpendicular and parallel to the flat face of the cable. The effect of the bending on the interstrand coupling losses could be neglected for the non-cored samples. The interstrand coupling losses of NiCr cored sample decreased by about 30% compared with the non-cored samples, in case the direction of the transverse magnetic fields applied to the cable is perpendicular to the flat face of the cable. Using these results and 2D-FEM analyses, taking into account that interstrand contact conditions vary from the center to the edge in the cross-section of cables, gave us the conclusion that the between side-by-side strands contact with metallurgical bond only in both edges of the cables.
System and method for sub-sea cable termination
Chen, Qin; Yin, Weijun; Zhang, Lili
2016-04-05
An electrical connector includes a first cable termination chamber configured to receive a first power cable having at least a first conductor sheathed at least in part by a first insulating layer and a first insulation screen layer. Also, the electrical connector includes a first non-linear resistive layer configured to be coupled to a portion of the first conductor unsheathed by at least the first insulation screen layer and configured to control a direct current electric field generated in the first cable termination chamber. In addition, the electrical connector includes a first deflector configured to be coupled to the first power cable and control an alternating current electric field generated in the first cable termination chamber.
46 CFR 28.370 - Wiring methods and materials.
Code of Federal Regulations, 2014 CFR
2014-10-01
... that affects one cable does not affect the other. (d) Cable and wire for power and lighting circuits... Operate With More Than 16 Individuals on Board § 28.370 Wiring methods and materials. (a) All cable and... circuit. (b) Each conductor must be No. 22 AWG or larger. Conductors in power and lighting circuits must...
46 CFR 28.370 - Wiring methods and materials.
Code of Federal Regulations, 2012 CFR
2012-10-01
... that affects one cable does not affect the other. (d) Cable and wire for power and lighting circuits... Operate With More Than 16 Individuals on Board § 28.370 Wiring methods and materials. (a) All cable and... circuit. (b) Each conductor must be No. 22 AWG or larger. Conductors in power and lighting circuits must...
46 CFR 28.370 - Wiring methods and materials.
Code of Federal Regulations, 2013 CFR
2013-10-01
... that affects one cable does not affect the other. (d) Cable and wire for power and lighting circuits... Operate With More Than 16 Individuals on Board § 28.370 Wiring methods and materials. (a) All cable and... circuit. (b) Each conductor must be No. 22 AWG or larger. Conductors in power and lighting circuits must...
Code of Federal Regulations, 2012 CFR
2012-07-01
... wires not insulated from one another, suitable for carrying an electric current. Electric Cable. An assembly of one or more insulated conductors of electric current under a common or integral jacket. A cable... the primary electric current or power is transmitted. Signaling Cable. A fiber optic cable, or a cable...
Code of Federal Regulations, 2014 CFR
2014-07-01
... wires not insulated from one another, suitable for carrying an electric current. Electric Cable. An assembly of one or more insulated conductors of electric current under a common or integral jacket. A cable... the primary electric current or power is transmitted. Signaling Cable. A fiber optic cable, or a cable...
Code of Federal Regulations, 2013 CFR
2013-07-01
... wires not insulated from one another, suitable for carrying an electric current. Electric Cable. An assembly of one or more insulated conductors of electric current under a common or integral jacket. A cable... the primary electric current or power is transmitted. Signaling Cable. A fiber optic cable, or a cable...
47 CFR 76.611 - Cable television basic signal leakage performance criteria.
Code of Federal Regulations, 2014 CFR
2014-10-01
... average power level of the strongest cable television carrier on the system. (c) In paragraph (a)(1) and... 47 Telecommunication 4 2014-10-01 2014-10-01 false Cable television basic signal leakage...) BROADCAST RADIO SERVICES MULTICHANNEL VIDEO AND CABLE TELEVISION SERVICE Technical Standards § 76.611 Cable...
30 CFR 77.600 - Trailing cables; short-circuit protection; disconnecting devices.
Code of Federal Regulations, 2014 CFR
2014-07-01
... capacity in each ungrounded conductor. Disconnecting devices used to disconnect power from trailing cables... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Trailing cables; short-circuit protection... AREAS OF UNDERGROUND COAL MINES Trailing Cables § 77.600 Trailing cables; short-circuit protection...
30 CFR 77.600 - Trailing cables; short-circuit protection; disconnecting devices.
Code of Federal Regulations, 2013 CFR
2013-07-01
... capacity in each ungrounded conductor. Disconnecting devices used to disconnect power from trailing cables... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Trailing cables; short-circuit protection... AREAS OF UNDERGROUND COAL MINES Trailing Cables § 77.600 Trailing cables; short-circuit protection...
47 CFR 76.611 - Cable television basic signal leakage performance criteria.
Code of Federal Regulations, 2013 CFR
2013-10-01
... average power level of the strongest cable television carrier on the system. (c) In paragraph (a)(1) and... 47 Telecommunication 4 2013-10-01 2013-10-01 false Cable television basic signal leakage...) BROADCAST RADIO SERVICES MULTICHANNEL VIDEO AND CABLE TELEVISION SERVICE Technical Standards § 76.611 Cable...
30 CFR 77.600 - Trailing cables; short-circuit protection; disconnecting devices.
Code of Federal Regulations, 2012 CFR
2012-07-01
... capacity in each ungrounded conductor. Disconnecting devices used to disconnect power from trailing cables... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Trailing cables; short-circuit protection... AREAS OF UNDERGROUND COAL MINES Trailing Cables § 77.600 Trailing cables; short-circuit protection...
47 CFR 76.611 - Cable television basic signal leakage performance criteria.
Code of Federal Regulations, 2012 CFR
2012-10-01
... average power level of the strongest cable television carrier on the system. (c) In paragraph (a)(1) and... 47 Telecommunication 4 2012-10-01 2012-10-01 false Cable television basic signal leakage...) BROADCAST RADIO SERVICES MULTICHANNEL VIDEO AND CABLE TELEVISION SERVICE Technical Standards § 76.611 Cable...
30 CFR 77.600 - Trailing cables; short-circuit protection; disconnecting devices.
Code of Federal Regulations, 2011 CFR
2011-07-01
... capacity in each ungrounded conductor. Disconnecting devices used to disconnect power from trailing cables... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Trailing cables; short-circuit protection... AREAS OF UNDERGROUND COAL MINES Trailing Cables § 77.600 Trailing cables; short-circuit protection...
Cable Television, Market Power and Regulation.
ERIC Educational Resources Information Center
Thorpe, Kenneth E.
The goals of this dissertation are to provide an empirical examination of the impact of competing technologies on cable television firms and to document existing pricing behavior in the cable and pay programming industry. The introduction provides a brief overview of the cable television industry, including the impact of cable on federal policy…
30 CFR 75.516 - Power wires; support.
Code of Federal Regulations, 2014 CFR
2014-07-01
... MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Electrical Equipment-General § 75.516 Power wires; support. [Statutory Provision] All power wires (except trailing cables on mobile equipment, specially designed cables... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Power wires; support. 75.516 Section 75.516...
30 CFR 75.516 - Power wires; support.
Code of Federal Regulations, 2012 CFR
2012-07-01
... MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Electrical Equipment-General § 75.516 Power wires; support. [Statutory Provision] All power wires (except trailing cables on mobile equipment, specially designed cables... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Power wires; support. 75.516 Section 75.516...
30 CFR 75.516 - Power wires; support.
Code of Federal Regulations, 2013 CFR
2013-07-01
... MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Electrical Equipment-General § 75.516 Power wires; support. [Statutory Provision] All power wires (except trailing cables on mobile equipment, specially designed cables... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Power wires; support. 75.516 Section 75.516...
30 CFR 75.516 - Power wires; support.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Power wires; support. 75.516 Section 75.516... MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Electrical Equipment-General § 75.516 Power wires; support. [Statutory Provision] All power wires (except trailing cables on mobile equipment, specially designed cables...
30 CFR 75.516 - Power wires; support.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Power wires; support. 75.516 Section 75.516... MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Electrical Equipment-General § 75.516 Power wires; support. [Statutory Provision] All power wires (except trailing cables on mobile equipment, specially designed cables...
85. INCLINED PLANE 7 EAST. FLUME AND STONE POWER HOUSE ...
85. INCLINED PLANE 7 EAST. FLUME AND STONE POWER HOUSE ARE ON RIGHT SIDE OF PHOTOGRAPH. NOTE THE CABLE LEAVING THE POWER HOUSE. THIS CABLE IS ATTATCHED TO A DRUM ON THE INSIDE THE POWER HOUSE WHICH IS TURNED BY MEANS OF A WATER POWERED TURBINE. - Morris Canal, Phillipsburg, Warren County, NJ
Visible to Near-infrared Spectral Reflectance, NGEE-Arctic Tram, Barrow, Alaska, 2015-2017
DOE Office of Scientific and Technical Information (OSTI.GOV)
Meng, Ran; McMahon, Andrew; Rogers, Alistair
Canopy spectral reflectance collected from the NGEE-Arctic automated tram platform using a PP-Systems UniSpec-DC spectrometer. Downwelling radiance was measured using a 2 meter fiber optic cable connected to a cosine diffuser. Upwelling (i.e. reflected) radiance was measured using a 2 meter cable connected to a 12 degree field-of-view (FOV) lens. Canopy reflectance was calculated using the ratio of upwelling to downwelling radiance measured over a 99.99% reflectance Spectralon standard measured at the start of each measurement set.
Visible-Near Infrared (VNIR) and Shortwave Infrared (SWIR) Spectral Variability of Urban Materials
2013-03-01
extension). FieldSpec 4 spectrometer unit is contained in the backpack. The fiber optic cable and power cable for the contact probe are seen...spectroradiometer foreoptic (lens) is typically between 1 degree and 25 degrees when using natural lighting (or artificially lit in lab) but a bare fiber ... fiber optic cable and power cable for the contact probe are seen. In operation, the spectrometer is allowed to warm up prior to use for at least 30
30 CFR 7.407 - Test for flame resistance of electric cables and cable splices.
Code of Federal Regulations, 2011 CFR
2011-07-01
... midpoint of the splice. The specimen shall be free from external air currents during testing. (5) Adjust... persistence of yellow coloration. (6) Connect all power conductors of the test specimen to the current source. The connections shall be secure and compatible with the size of the cable's power conductors in order...
30 CFR 7.407 - Test for flame resistance of electric cables and cable splices.
Code of Federal Regulations, 2010 CFR
2010-07-01
... midpoint of the splice. The specimen shall be free from external air currents during testing. (5) Adjust... persistence of yellow coloration. (6) Connect all power conductors of the test specimen to the current source. The connections shall be secure and compatible with the size of the cable's power conductors in order...
Noise propagation issues in Belle II pixel detector power cable
Iglesias, M.; Arteche, F.; Echeverria, I.; ...
2018-04-26
The vertex detector used in the upgrade of High-Energy physics experiment Belle II includes DEPFET pixel detector (PXD) technology. In this complex topology the power supply units and the front-end electronics are connected through a PXD power cable bundle which may propagate the output noise from the power supplies to the vertex area. This article presents a study of the propagation of noise caused by power converters in the PXD cable bundle based on Multi-conductor Transmission Line (MTL) theory. The work exposes the effect of the complex cable topology and shield connections on the noise propagation, which has an impactmore » on the requirements of the power supplies. This analysis is part of the electromagnetic compatibility based design focused on functional safety to define the shield connections and power supply specifications required to ensure the successful integration of the detector and, specifically, to achieve the designed performance of the front-end electronics.« less
Noise propagation issues in Belle II pixel detector power cable
DOE Office of Scientific and Technical Information (OSTI.GOV)
Iglesias, M.; Arteche, F.; Echeverria, I.
The vertex detector used in the upgrade of High-Energy physics experiment Belle II includes DEPFET pixel detector (PXD) technology. In this complex topology the power supply units and the front-end electronics are connected through a PXD power cable bundle which may propagate the output noise from the power supplies to the vertex area. This article presents a study of the propagation of noise caused by power converters in the PXD cable bundle based on Multi-conductor Transmission Line (MTL) theory. The work exposes the effect of the complex cable topology and shield connections on the noise propagation, which has an impactmore » on the requirements of the power supplies. This analysis is part of the electromagnetic compatibility based design focused on functional safety to define the shield connections and power supply specifications required to ensure the successful integration of the detector and, specifically, to achieve the designed performance of the front-end electronics.« less
A wireless smart sensor network for automated monitoring of cable tension
NASA Astrophysics Data System (ADS)
Sim, Sung-Han; Li, Jian; Jo, Hongki; Park, Jong-Woong; Cho, Soojin; Spencer, Billie F., Jr.; Jung, Hyung-Jo
2014-02-01
As cables are primary load carrying members in cable-stayed bridges, monitoring the tension forces of the cables provides valuable information regarding structural soundness. Incorporating wireless smart sensors with vibration-based tension estimation methods provides an efficient means of autonomous long-term monitoring of cable tensions. This study develops a wireless cable tension monitoring system using MEMSIC’s Imote2 smart sensors. The monitoring system features autonomous operation, sustainable energy harvesting and power consumption, and remote access using the internet. To obtain the tension force, an in-network data processing strategy associated with the vibration-based tension estimation method is implemented on the Imote2-based sensor network, significantly reducing the wireless data transmission and the power consumption. The proposed monitoring system has been deployed and validated on the Jindo Bridge, a cable-stayed bridge located in South Korea.
1980-08-01
knots Figure 14. Current profile. 84 6; * .4. 0 E U U U -~ U U (.4 U @0 85 I UECfLI ?E)r eAtE NjKC 7 frCAd I o .,01 U.I 75o* ANL I U,) I000. 0.) AKC 3 U...NAVSCOLCECOFF C35 Port Hueneme, CA NAVSEASYSCOM Code SEA OOC Washington. DC NAVSEC Code 6034 (Library), Washington DC NAVSHIPREPFAC Library. Guam NAVSHIPYD Code
30 CFR 57.12088 - Splicing trailing cables.
Code of Federal Regulations, 2014 CFR
2014-07-01
... cable reel or other power feed cable payout-retrieval system. However, a temporary splice may be made to... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Splicing trailing cables. 57.12088 Section 57... Underground Only § 57.12088 Splicing trailing cables. No splice, except a vulcanized splice or its equivalent...
30 CFR 57.12088 - Splicing trailing cables.
Code of Federal Regulations, 2011 CFR
2011-07-01
... cable reel or other power feed cable payout-retrieval system. However, a temporary splice may be made to... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Splicing trailing cables. 57.12088 Section 57... Underground Only § 57.12088 Splicing trailing cables. No splice, except a vulcanized splice or its equivalent...
30 CFR 57.12088 - Splicing trailing cables.
Code of Federal Regulations, 2013 CFR
2013-07-01
... cable reel or other power feed cable payout-retrieval system. However, a temporary splice may be made to... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Splicing trailing cables. 57.12088 Section 57... Underground Only § 57.12088 Splicing trailing cables. No splice, except a vulcanized splice or its equivalent...
30 CFR 57.12088 - Splicing trailing cables.
Code of Federal Regulations, 2012 CFR
2012-07-01
... cable reel or other power feed cable payout-retrieval system. However, a temporary splice may be made to... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Splicing trailing cables. 57.12088 Section 57... Underground Only § 57.12088 Splicing trailing cables. No splice, except a vulcanized splice or its equivalent...
Probabilistic models to estimate fire-induced cable damage at nuclear power plants
NASA Astrophysics Data System (ADS)
Valbuena, Genebelin R.
Even though numerous PRAs have shown that fire can be a major contributor to nuclear power plant risk, there are some specific areas of knowledge related to this issue, such as the prediction of fire-induced damage to electrical cables and circuits, and their potential effects in the safety of the nuclear power plant, that still constitute a practical enigma, particularly for the lack of approaches/models to perform consistent and objective assessments. This report contains a discussion of three different models to estimate fire-induced cable damage likelihood given a specified fire profile: the kinetic, the heat transfer and the IR "K Factor" model. These models not only are based on statistical analysis of data available in the open literature, but to the greatest extent possible they use physics based principles to describe the underlying mechanism of failures that take place among the electrical cables upon heating due to external fires. The characterization of cable damage, and consequently the loss of functionality of electrical cables in fire is a complex phenomenon that depends on a variety of intrinsic factors such as cable materials and dimensions, and extrinsic factors such as electrical and mechanical loads on the cables, heat flux severity, and exposure time. Some of these factors are difficult to estimate even in a well-characterized fire, not only for the variability related to the unknown material composition and physical arrangements, but also for the lack of objective frameworks and theoretical models to study the behavior of polymeric wire cable insulation under dynamic external thermal insults. The results of this research will (1) help to develop a consistent framework to predict fire-induced cable failure modes likelihood, and (2) develop some guidance to evaluate and/or reduce the risk associated with these failure modes in existing and new power plant facilities. Among the models evaluated, the physics-based heat transfer model takes into account the properties and characteristics of the cables and cable materials, and the characteristics of the thermal insult. This model can be used to estimate the probability of cable damage under different thermal conditions.
Power transmission cable development for the Space Station Freedom electrical power system
NASA Technical Reports Server (NTRS)
Schmitz, Gregory V.; Biess, John J.
1989-01-01
Power transmission cable is presently being evaluated under a NASA Lewis Research Center advanced development contract for application in the Space Station Freedom (SSF) electrical power system (EPS). Evaluation testing has been performed by TRW and NASA Lewis Research Center. The results of this development contract are presented. The primary cable design goals are to provide (1) a low characteristic inductance to minimize line voltage drop at 20 kHz, (2) electromagnetic compatibility control of the 20-kHz ac power current, (3) a physical configuration that minimizes ac resistance and (4) release of trapped air for corona-free operation.
High temperature superconductors as a technological discontinuity in the power cable industry
DOE Office of Scientific and Technical Information (OSTI.GOV)
Beales, T.P.; McCormack, J.S.
1994-12-31
The advent of superconductivity above 77 K represents to the power cable industry a technological discontinuity analogous to that seen in the copper telecommunications industry by the arrival of optical fibres. This phenomenon is discussed along with technical criteria and performance targets needed for high temperature superconducting wire to have an economic impact in transmission cables.
High temperature superconductors as a technological discontinuity in the power cable industry
NASA Technical Reports Server (NTRS)
Beales, T. P.; Mccormack, J. S.
1995-01-01
The advent of superconductivity above 77 K represents to the power cable industry a technological discontinuity analogous to that seen in the copper telecommunications industry by the arrival of optical fibers. This phenomenon is discussed along with technical criteria and performance targets needed for high temperature superconducting wire to have an economic impact in transmission cables.
Code of Federal Regulations, 2014 CFR
2014-10-01
... requirements: (a) A shore power connection box or receptacle and a cable connecting this box or receptacle to... power cable must be provided with a disconnect means located on or near the main distribution panel... 46 Shipping 7 2014-10-01 2014-10-01 false Shore power. 169.686 Section 169.686 Shipping COAST...
Code of Federal Regulations, 2012 CFR
2012-10-01
... requirements: (a) A shore power connection box or receptacle and a cable connecting this box or receptacle to... power cable must be provided with a disconnect means located on or near the main distribution panel... 46 Shipping 7 2012-10-01 2012-10-01 false Shore power. 169.686 Section 169.686 Shipping COAST...
Code of Federal Regulations, 2013 CFR
2013-10-01
... requirements: (a) A shore power connection box or receptacle and a cable connecting this box or receptacle to... power cable must be provided with a disconnect means located on or near the main distribution panel... 46 Shipping 7 2013-10-01 2013-10-01 false Shore power. 169.686 Section 169.686 Shipping COAST...
46 CFR 111.60-4 - Minimum cable conductor size.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 46 Shipping 4 2010-10-01 2010-10-01 false Minimum cable conductor size. 111.60-4 Section 111.60-4...-GENERAL REQUIREMENTS Wiring Materials and Methods § 111.60-4 Minimum cable conductor size. Each cable conductor must be #18 AWG (0.82 mm2) or larger except— (a) Each power and lighting cable conductor must be...
46 CFR 111.60-4 - Minimum cable conductor size.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 46 Shipping 4 2011-10-01 2011-10-01 false Minimum cable conductor size. 111.60-4 Section 111.60-4...-GENERAL REQUIREMENTS Wiring Materials and Methods § 111.60-4 Minimum cable conductor size. Each cable conductor must be #18 AWG (0.82 mm2) or larger except— (a) Each power and lighting cable conductor must be...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hartlein, Rick; Hampton, Nigel; Perkel, Josh
2016-02-01
The Cable Diagnostic Focused Initiative (CDFI) played a significant and powerful role in clarifying the concerns and understanding the benefits of performing diagnostic tests on underground power cable systems. This project focused on the medium and high voltage cable systems used in utility transmission and distribution (T&D) systems. While many of the analysis techniques and interpretations are applicable to diagnostics and cable systems outside of T&D, areas such as generating stations (nuclear, coal, wind, etc.) and other industrial environments were not the focus. Many large utilities in North America now deploy diagnostics or have changed their diagnostic testing approach asmore » a result of this project. Previous to the CDFI, different diagnostic technology providers individually promoted their approach as the “the best” or “the only” means of detecting cable system defects.« less
NASA Astrophysics Data System (ADS)
Taylor, Gabriel James
The failure of electrical cables exposed to severe thermal fire conditions are a safety concern for operating commercial nuclear power plants (NPPs). The Nuclear Regulatory Commission (NRC) has promoted the use of risk-informed and performance-based methods for fire protection which resulted in a need to develop realistic methods to quantify the risk of fire to NPP safety. Recent electrical cable testing has been conducted to provide empirical data on the failure modes and likelihood of fire-induced damage. This thesis evaluated numerous aspects of the data. Circuit characteristics affecting fire-induced electrical cable failure modes have been evaluated. In addition, thermal failure temperatures corresponding to cable functional failures have been evaluated to develop realistic single point thermal failure thresholds and probability distributions for specific cable insulation types. Finally, the data was used to evaluate the prediction capabilities of a one-dimension conductive heat transfer model used to predict cable failure.
Mobile Uninterruptible Power Supply
NASA Technical Reports Server (NTRS)
Mears, Robert L.
1990-01-01
Proposed mobile unit provides 20 kVA of uninterruptible power. Used with mobile secondary power-distribution centers to provide power to test equipment with minimal cabling, hazards, and obstacles. Wheeled close to test equipment and system being tested so only short cable connections needed. Quickly moved and set up in new location. Uninterruptible power supply intended for tests which data lost or equipment damaged during even transient power failure.
Safety research of insulating materials of cable for nuclear power generating station
NASA Technical Reports Server (NTRS)
Lee, C. K.; Choi, J. H.; Kong, Y. K.; Chang, H. S.
1988-01-01
The polymers PE, EPR, PVC, Neoprene, CSP, CLPE, EP and other similar substances are frequently used as insulation and protective covering for cables used in nuclear power generating stations. In order to test these materials for flame retardation, environmental resistance, and cable specifications, they were given the cable normal test, flame test, chemical tests, and subjected to design analysis and loss of coolant accident tests. Material was collected on spark tests and actual experience standards were established through these contributions and technology was accumulated.
NASA Astrophysics Data System (ADS)
Tuckerman, David B.; Hamilton, Michael C.; Reilly, David J.; Bai, Rujun; Hernandez, George A.; Hornibrook, John M.; Sellers, John A.; Ellis, Charles D.
2016-08-01
We describe progress and initial results achieved towards the goal of developing integrated multi-conductor arrays of shielded controlled-impedance flexible superconducting transmission lines with ultra-miniature cross sections and wide bandwidths (dc to >10 GHz) over meter-scale lengths. Intended primarily for use in future scaled-up quantum computing systems, such flexible thin-film niobium/polyimide ribbon cables could provide a physically compact and ultra-low thermal conductance alternative to the rapidly increasing number of discrete coaxial cables that are currently used by quantum computing experimentalists to transmit signals between the several low-temperature stages (from ˜4 K down to ˜20 mK) of a dilution refrigerator. We have concluded that these structures are technically feasible to fabricate, and so far they have exhibited acceptable thermo-mechanical reliability. S-parameter results are presented for individual 2-metal layer Nb microstrip structures having 50 Ω characteristic impedance; lengths ranging from 50 to 550 mm were successfully fabricated. Solderable pads at the end terminations allowed testing using conventional rf connectors. Weakly coupled open-circuit microstrip resonators provided a sensitive measure of the overall transmission line loss as a function of frequency, temperature, and power. Two common microelectronic-grade polyimide dielectrics, one conventional and the other photo-definable (PI-2611 and HD-4100, respectively) were compared. Our most striking result, not previously reported to our knowledge, was that the dielectric loss tangents of both polyimides, over frequencies from 1 to 20 GHz, are remarkably low at deep cryogenic temperatures, typically 100× smaller than corresponding room temperature values. This enables fairly long-distance (meter-scale) transmission of microwave signals without excessive attenuation, and also permits usefully high rf power levels to be transmitted without creating excessive dielectric heating. We observed loss tangents as low as 2.2 × 10-5 at 20 mK, although losses increased somewhat at very low rf power levels, similar to the well-known behavior of amorphous inorganic dielectrics such as SiO2. Our fabrication techniques could be extended to more complex structures such as multiconductor cables, embedded microstrip, 3-metal layer stripline or rectangular coax, and integrated attenuators and thermalization structures.
Isolated and soft-switched power converter
Peng, Fang Zheng; Adams, Donald Joe
2002-01-01
An isolated and soft-switched power converter is used for DC/DC and DC/DC/AC power conversion. The power converter includes two resonant tank circuits coupled back-to-back through an isolation transformer. Each resonant tank circuit includes a pair of resonant capacitors connected in series as a resonant leg, a pair of tank capacitors connected in series as a tank leg, and a pair of switching devices with anti-parallel clamping diodes coupled in series as resonant switches and clamping devices for the resonant leg. The power converter is well suited for DC/DC and DC/DC/AC power conversion applications in which high-voltage isolation, DC to DC voltage boost, bidirectional power flow, and a minimal number of conventional switching components are important design objectives. For example, the power converter is especially well suited to electric vehicle applications and load-side electric generation and storage systems, and other applications in which these objectives are important. The power converter may be used for many different applications, including electric vehicles, hybrid combustion/electric vehicles, fuel-cell powered vehicles with low-voltage starting, remote power sources utilizing low-voltage DC power sources, such as photovoltaics and others, electric power backup systems, and load-side electric storage and generation systems.
Sassi, C G; Cameli, M; Dokollari, A; Diciolla, F; Scolletta, S; Ricci, C; Lucatelli, P; Mondillo, S; Maccherini, M
2017-05-01
There are limited clinical reports concerning internal power cable fixing in left ventricular assist device (L-VAD) patients. Actually there are no reports in the literature about Jarvik 2000 internal cable repair. We show the first description of a technique for surgical reparation of such a fatal complication. The patient was a 62-year-old woman who had L-VAD implantation (Jarvik 2000) with outflow graft apposition in descending thoracic aorta through left thoracotomy access, in 2009. She arrived urgently on January 25, 2014 for Jarvik 2000 dysfunction correlated with head movements. The neck X-rays revealed the rupture of one of the nine power cables located inside the neck and the damaging of two more cables nearby to be ruptured. On the same day she got pump failure due to the final interruption of the remaining two cables, we were obliged to install femoro-femoral extracorporeal membrane oxygenation (ECMO) assistance, to repair the power cables, approaching them through a pacemaker extension cable. The L-VAD outflow was occluded with vascular ball occluder inserted via right axillary artery under fluoroscopy before ECMO installation. At the end the ECMO assistance was interrupted and the Jarvik 2000 was turned back on. The patient was dismissed from the hospital 12 days after the procedure. At the moment the international literature is poor regarding this issue. This case provides evidence that in emergency conditions ECMO assistance is mandatory and a hybrid surgical and radiological approach could help to repair the damage in safe conditions. Copyright © 2017 Elsevier Inc. All rights reserved.
Study on AC loss measurements of HTS power cable for standardizing
NASA Astrophysics Data System (ADS)
Mukoyama, Shinichi; Amemiya, Naoyuki; Watanabe, Kazuo; Iijima, Yasuhiro; Mido, Nobuhiro; Masuda, Takao; Morimura, Toshiya; Oya, Masayoshi; Nakano, Tetsutaro; Yamamoto, Kiyoshi
2017-09-01
High-temperature superconducting power cables (HTS cables) have been developed for more than 20 years. In addition of the cable developments, the test methods of the HTS cables have been discussed and proposed in many laboratories and companies. Recently the test methods of the HTS cables is required to standardize and to common in the world. CIGRE made the working group (B1-31) for the discussion of the test methods of the HTS cables as a power cable, and published the recommendation of the test method. Additionally, IEC TC20 submitted the New Work Item Proposal (NP) based on the recommendation of CIGRE this year, IEC TC20 and IEC TC90 started the standardization work on Testing of HTS AC cables. However, the individual test method that used to measure a performance of HTS cables hasn’t been established as world’s common methods. The AC loss is one of the most important properties to disseminate low loss and economical efficient HTS cables in the world. We regard to establish the method of the AC loss measurements in rational and in high accuracy. Japan is at a leading position in the AC loss study, because Japanese researchers have studied on the AC loss technically and scientifically, and also developed the effective technologies for the AC loss reduction. The JP domestic commission of TC90 made a working team to discussion the methods of the AC loss measurements for aiming an international standard finally. This paper reports about the AC loss measurement of two type of the HTS conductors, such as a HTS conductor without a HTS shield and a HTS conductor with a HTS shield. The AC loss measurement method is suggested by the electrical method..
National Maglev initiative: California line electric utility power system requirements
NASA Technical Reports Server (NTRS)
Save, Phil
1994-01-01
The electrical utility power system requirements were determined for a Maglev line from San Diego to San Francisco and Sacramento with a maximum capacity of 12,000 passengers an hour in each direction at a speed of 300 miles per hour, or one train every 30 seconds in each direction. Basically the Maglev line requires one 50-MVA substation every 12.5 miles. The need for new power lines to serve these substations and their voltage levels are based not only on equipment loading criteria but also on limitations due to voltage flicker and harmonics created by the Maglev system. The resulting power system requirements and their costs depend mostly on the geographical area, urban or suburban with 'strong' power systems, or mountains and rural areas with 'weak' power systems. A reliability evaluation indicated that emergency power sources, such as a 10-MW battery at each substation, were not justified if sufficient redundancy is provided in the design of the substations and the power lines serving them. With a cost of $5.6 M per mile, the power system requirements, including the 12-kV DC cables and the inverters along the Maglev line, were found to be the second largest cost component of the Maglev system, after the cost of the guideway system ($9.1 M per mile), out of a total cost of $23 M per mile.
Description of a 20 kilohertz power distribution system
NASA Technical Reports Server (NTRS)
Hansen, I. G.
1986-01-01
A single phase, 440 VRMS, 20 kHz power distribution system with a regulated sinusoidal wave form is discussed. A single phase power system minimizes the wiring, sensing, and control complexities required in a multi-sourced redundantly distributed power system. The single phase addresses only the distribution links multiphase lower frequency inputs and outputs accommodation techniques are described. While the 440 V operating potential was initially selected for aircraft operating below 50,000 ft, this potential also appears suitable for space power systems. This voltage choice recognizes a reasonable upper limit for semiconductor ratings, yet will direct synthesis of 220 V, 3 power. A 20 kHz operating frequency was selected to be above the range of audibility, minimize the weight of reactive components, yet allow the construction of single power stages of 25 to 30 kW. The regulated sinusoidal distribution system has several advantages. With a regulated voltage, most ac/dc conversions involve rather simple transformer rectifier applications. A sinusoidal distribution system, when used in conjunction with zero crossing switching, represents a minimal source of EMI. The present state of 20 kHz power technology includes computer controls of voltage and/or frequency, low inductance cable, current limiting circuit protection, bi-directional power flow, and motor/generator operating using standard induction machines. A status update and description of each of these items and their significance is presented.
Description of a 20 Kilohertz power distribution system
NASA Technical Reports Server (NTRS)
Hansen, I. G.
1986-01-01
A single phase, 440 VRMS, 20 kHz power distribution system with a regulated sinusoidal wave form is discussed. A single phase power system minimizes the wiring, sensing, and control complexities required in a multi-sourced redundantly distributed power system. The single phase addresses only the distribution link; mulitphase lower frequency inputs and outputs accommodation techniques are described. While the 440 V operating potential was initially selected for aircraft operating below 50,000 ft, this potential also appears suitable for space power systems. This voltage choice recognizes a reasonable upper limit for semiconductor ratings, yet will direct synthesis of 220 V, 3 power. A 20 kHz operating frequency was selected to be above the range of audibility, minimize the weight of reactive components, yet allow the construction of single power stages of 25 to 30 kW. The regulated sinusoidal distribution system has several advantages. With a regulated voltage, most ac/dc conversions involve rather simple transformer rectifier applications. A sinusoidal distribution system, when used in conjunction with zero crossing switching, represents a minimal source of EMI. The present state of 20 kHz power technology includes computer controls of voltage and/or frequency, low inductance cable, current limiting circuit protection, bi-directional power flow, and motor/generator operating using standard induction machines. A status update and description of each of these items and their significance is presented.
30 CFR 75.804 - Underground high-voltage cables.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Underground high-voltage cables. 75.804 Section... § 75.804 Underground high-voltage cables. (a) Underground high-voltage cables used in resistance grounded systems shall be equipped with metallic shields around each power conductor with one or more...
30 CFR 75.804 - Underground high-voltage cables.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Underground high-voltage cables. 75.804 Section... § 75.804 Underground high-voltage cables. (a) Underground high-voltage cables used in resistance grounded systems shall be equipped with metallic shields around each power conductor with one or more...
30 CFR 75.601 - Short circuit protection of trailing cables.
Code of Federal Regulations, 2012 CFR
2012-07-01
... to disconnect power from trailing cables shall be plainly marked and identified and such devices... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Short circuit protection of trailing cables. 75... MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Trailing Cables § 75.601 Short...
30 CFR 75.601 - Short circuit protection of trailing cables.
Code of Federal Regulations, 2011 CFR
2011-07-01
... to disconnect power from trailing cables shall be plainly marked and identified and such devices... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Short circuit protection of trailing cables. 75... MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Trailing Cables § 75.601 Short...
30 CFR 75.601 - Short circuit protection of trailing cables.
Code of Federal Regulations, 2014 CFR
2014-07-01
... to disconnect power from trailing cables shall be plainly marked and identified and such devices... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Short circuit protection of trailing cables. 75... MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Trailing Cables § 75.601 Short...
30 CFR 75.601 - Short circuit protection of trailing cables.
Code of Federal Regulations, 2013 CFR
2013-07-01
... to disconnect power from trailing cables shall be plainly marked and identified and such devices... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Short circuit protection of trailing cables. 75... MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Trailing Cables § 75.601 Short...
30 CFR 75.804 - Underground high-voltage cables.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Underground high-voltage cables. 75.804 Section... § 75.804 Underground high-voltage cables. (a) Underground high-voltage cables used in resistance grounded systems shall be equipped with metallic shields around each power conductor with one or more...
46 CFR 129.340 - Cable and wiring.
Code of Federal Regulations, 2011 CFR
2011-10-01
... buildup of condensation. (b) Each cable and wire must— (1) Have stranded copper conductors with sufficient... Power Sources and Distribution Systems § 129.340 Cable and wiring. (a) If individual wires, rather than cables, are used in systems operating at a potential of greater than 50 volts, the wire and associated...
46 CFR 129.340 - Cable and wiring.
Code of Federal Regulations, 2013 CFR
2013-10-01
... buildup of condensation. (b) Each cable and wire must— (1) Have stranded copper conductors with sufficient... Power Sources and Distribution Systems § 129.340 Cable and wiring. (a) If individual wires, rather than cables, are used in systems operating at a potential of greater than 50 volts, the wire and associated...
46 CFR 129.340 - Cable and wiring.
Code of Federal Regulations, 2014 CFR
2014-10-01
... buildup of condensation. (b) Each cable and wire must— (1) Have stranded copper conductors with sufficient... Power Sources and Distribution Systems § 129.340 Cable and wiring. (a) If individual wires, rather than cables, are used in systems operating at a potential of greater than 50 volts, the wire and associated...
46 CFR 129.340 - Cable and wiring.
Code of Federal Regulations, 2012 CFR
2012-10-01
... buildup of condensation. (b) Each cable and wire must— (1) Have stranded copper conductors with sufficient... Power Sources and Distribution Systems § 129.340 Cable and wiring. (a) If individual wires, rather than cables, are used in systems operating at a potential of greater than 50 volts, the wire and associated...
Medical devices utilizing optical fibers for simultaneous power, communications and control
Fitch, Joseph P.; Matthews, Dennis L.; Hagans, Karla G.; Lee, Abraham P.; Krulevitch, Peter; Benett, William J.; Clough, Robert E.; DaSilva, Luiz B.; Celliers, Peter M.
2003-06-10
A medical device is constructed in the basic form of a catheter having a distal end for insertion into and manipulation within a body and a proximal end providing for a user to control the manipulation of the distal end within the body. A fiberoptic cable is disposed within the catheter and having a distal end proximate to the distal end of the catheter and a proximal end for external coupling of laser light energy. A laser-light-to-mechanical-power converter is connected to receive light from the distal end of the fiber optic cable and may include a photo-voltaic cell and an electromechanical motor or a heat-sensitive photo-thermal material. An electronic sensor is connected to receive electrical power from said distal end of the fiberoptic cable and is connected to provide signal information about a particular physical environment and communicated externally through the fiberoptic cable to the proximal end thereof. A mechanical sensor is attached to the distal end of the fiberoptic cable and connected to provide light signal information about a particular physical environment and communicated externally through the fiberoptic cable.
HTS Transmission Cable System for installation in the Long Island Power Grid
DOE Office of Scientific and Technical Information (OSTI.GOV)
Schmidt, Frank; Durand, Fabien; Maguire, James
2015-10-05
Department of Energy (DOE) Award DE-FC26-07NT43240 was issued on October 1, 2007. Referred to as LIPA2, the principal objectives of the project were to develop key components required to deploy and demonstrate second-generation (2G) high temperature superconductor (HTS) cables in a 600 meter (2000 feet) underground segment of a 138kV three-phase transmission circuit of the Long Island Power Authority (LIPA) power grid. A previous effort under DOE Award DE-FC36-03GO13032 (referred to as LIPA1) resulted in installation (and subsequent successful operation) of first-generation (1G) HTS cables at the LIPA site. As with LIPA1, American Superconductor (AMSC) led the effort for LIPA2more » and was responsible for overall management of the project and producing sufficient 2G wire to fabricate the required cable. Nexans' tasks included design/manufacture/installation of the cable, joint (splice), cable terminations and field repairable cryostat; while work by Air Liquide involved engineering and installation support for the refrigeration system modifications.« less
Cabling design of booster and storage ring construction progress of TPS
NASA Astrophysics Data System (ADS)
Wong, Y.-S.; Liu, K.-B.; Liu, C.-Y.; Wang, b.-S.
2017-06-01
The 2012 Taiwan Photon Source (TPS) cable construction project started after 10 months to complete the cable laying and installation of power supply. The circumference of the booster ring (BR) is 496.8 m, whereas that of the storage ring (SR) is 518.4 m. Beam current is set to 500 mA at 3.3 GeV. The paper on grounding systems discusses the design of the ground wire (< 0.2 Ω) with low impedance, power supply of the accelerator and cabling tray. The flow and size of the ground current are carefully evaluated to avoid grounded current from flowing everywhere, which causes interference problems. In the design of the TPS, special shielding will be established to isolate the effects of electromagnetic interference on the magnet and ground current. Booster ring dipoles are connected by a series of 54-magnet bending dipole; the cable size of its stranded wire measures 250 mm2, with a total length of 5000 m. Booster ring and storage ring quadrupoles have 150 magnets; the cable size of their stranded wire is 250 mm2, with a total length of 17000 m. Storage ring dipole consists of 48 magnets; the cable size of its stranded wire is 325 mm2, with a total length of 6000 m. This study discusses the power supply cabling design of the storage ring and booster ring construction progress of TPS. The sections of this paper are divided into discussions of the construction of the control and instrument area, cabling layout of booster ring and storage ring, as well as the installation and commission machine. This study also discusses the use of a high-impedance meter to determine the effect of cabling insulation and TPS power supply machine on energy transfer to ensure the use of safe and correct magnet.
[Computation of the cross-sectional area of the cable in the power circuit of the X-ray machine].
Meng, Xin-min; Feng, Da-yu
2007-01-01
The source impedance of the power circuit in the x-ray machine is analyzed in the paper and based on the voltage drop generated by the impedance, the cross-sectional area of the cable is calculated. In the end, the cross-sectional areas of the cables, corresponding to their respective distances between the transformers and the switchboards are given.
78 FR 7642 - Airworthiness Directives; Piper Aircraft, Inc.
Federal Register 2010, 2011, 2012, 2013, 2014
2013-02-04
...., Washington, DC 20590. FOR FURTHER INFORMATION CONTACT: Hector Hernandez, Aerospace Engineer, FAA, Atlanta.... Conclusion We reviewed the relevant data, considered the comments received, and determined that air safety... work-hours x $85 per hour = $608 $1,458 system--per set of cables. $850. Authority for This Rulemaking...
77 FR 18869 - Cable Statutory License: Specialty Station List
Federal Register 2010, 2011, 2012, 2013, 2014
2012-03-28
.... Sandros, Deputy General Counsel, Copyright GC/I&R, P.O. Box 70400, Southwest Station, Washington, DC 20024... television broadcast station that generally carries foreign-language, religious, and/or automated programming... Office attesting to the fact that the station's programming comports with the 1981 FCC definition, and...
Repairing Damaged Power-Cable Insulation
NASA Technical Reports Server (NTRS)
Baker, G. E.
1984-01-01
Simple method saves time, money, and material. In new method cable remains in place while new insulation is applied to damaged portion. Method results in new terminations with safety factor equal to that of any portion of cable.
Time-delayed directional beam phased array antenna
Fund, Douglas Eugene; Cable, John William; Cecil, Tony Myron
2004-10-19
An antenna comprising a phased array of quadrifilar helix or other multifilar antenna elements and a time-delaying feed network adapted to feed the elements. The feed network can employ a plurality of coaxial cables that physically bridge a microstrip feed circuitry to feed power signals to the elements. The cables provide an incremental time delay which is related to their physical lengths, such that replacing cables having a first set of lengths with cables having a second set of lengths functions to change the time delay and shift or steer the antenna's main beam. Alternatively, the coaxial cables may be replaced with a programmable signal processor unit adapted to introduce the time delay using signal processing techniques applied to the power signals.
4He sample probe for combined microwave and dc transport measurements
NASA Astrophysics Data System (ADS)
Dobrovolskiy, Oleksandr V.; Franke, Jörg; Huth, Michael
2015-03-01
Combined microwave and dc electrical transport measurements at low temperatures represent a valuable experimental method in many research areas. In particular, when samples are conventional superconductors, a typical experiment requires a combination of helium temperatures, a wide range of magnetic fields, and the utilization of coaxial lines along with the usual dc wiring. We report on the general design features and the microwave performance of a custom-made low-temperature sample probe, with a measurement bandwidth tested from dc to 20 GHz. Equipped with six coaxial cables, a heater, Hall and temperature sensors, the probe fits into a ⊘32 mm shaft. We present our setup, analyze its microwave performance, and describe two representative experiments enabled by this system. The proposed setup will be essential for a systematic study of the dc and ac response of the vortex dynamics in nanopatterned superconductors subject to combined dc and microwave stimuli. Besides, it will be valuable for the investigation of a broad class of nonlinear stochastic systems where a combination of dc and high-frequency ac driving in a wide temperature range is necessary.
NASA Astrophysics Data System (ADS)
Schmidt, F.
1980-11-01
The components of a superconducting 110 kV ac cable for power ratings or = 2000 MVA were developed. The cable design is of the semiflexible type, with a rigid cryogenic envelope containing a flexible hollow coaxial cable core. The cable core consists of spirally wound Nb-A1 composite wires electrically insulated by high pressure polyethylene tape wrappings. A 35 m long single phase test cable with full load terminals rated at 110 kV and 10 kA was constructed and successfully tested. The results obtained prove the technical feasibility and capability of this cable design.
Portable Power And Digital-Communication Units
NASA Technical Reports Server (NTRS)
Levin, Richard R.; Henry, Paul K.; Rosenberg, Leigh S.
1992-01-01
Conceptual network of electronic-equipment modules provides electrical power and digital radio communications at multiple sites not served by cables. System includes central communication unit and portable units powered by solar photovoltaic arrays. Useful to serve equipment that must be set up quickly at remote sites or buildings that cannot be modified to provide cable connections.
33 CFR 80.707 - Cape Romain, SC to Sullivans Island, SC.
Code of Federal Regulations, 2013 CFR
2013-07-01
... the easternmost extremity of Capers Island. (d) A line formed by the overhead power cable from Capers Island to Dewees Island. (e) A line formed by the overhead power cable from Dewees Island to Isle of...
47. BASE OF UMBILICAL MAST, WITH ELECTRICAL POWER CABLES ON ...
47. BASE OF UMBILICAL MAST, WITH ELECTRICAL POWER CABLES ON LEFT; AIR-CONDITIONER DUCTS ON RIGHT - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA
33 CFR 80.707 - Cape Romain, SC to Sullivans Island, SC.
Code of Federal Regulations, 2014 CFR
2014-07-01
... the easternmost extremity of Capers Island. (d) A line formed by the overhead power cable from Capers Island to Dewees Island. (e) A line formed by the overhead power cable from Dewees Island to Isle of...
30 CFR 57.22311 - Electrical cables (II-A mines).
Code of Federal Regulations, 2013 CFR
2013-07-01
... Standards for Methane in Metal and Nonmetal Mines Equipment § 57.22311 Electrical cables (II-A mines). Only jacketed electrical cables accepted or approved by MSHA as flame resistant shall be used to supply power to... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Electrical cables (II-A mines). 57.22311...
30 CFR 57.22311 - Electrical cables (II-A mines).
Code of Federal Regulations, 2012 CFR
2012-07-01
... Standards for Methane in Metal and Nonmetal Mines Equipment § 57.22311 Electrical cables (II-A mines). Only jacketed electrical cables accepted or approved by MSHA as flame resistant shall be used to supply power to... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Electrical cables (II-A mines). 57.22311...
30 CFR 57.22311 - Electrical cables (II-A mines).
Code of Federal Regulations, 2010 CFR
2010-07-01
... Standards for Methane in Metal and Nonmetal Mines Equipment § 57.22311 Electrical cables (II-A mines). Only jacketed electrical cables accepted or approved by MSHA as flame resistant shall be used to supply power to... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Electrical cables (II-A mines). 57.22311...
30 CFR 57.22311 - Electrical cables (II-A mines).
Code of Federal Regulations, 2011 CFR
2011-07-01
... Standards for Methane in Metal and Nonmetal Mines Equipment § 57.22311 Electrical cables (II-A mines). Only jacketed electrical cables accepted or approved by MSHA as flame resistant shall be used to supply power to... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Electrical cables (II-A mines). 57.22311...
30 CFR 57.22311 - Electrical cables (II-A mines).
Code of Federal Regulations, 2014 CFR
2014-07-01
... Standards for Methane in Metal and Nonmetal Mines Equipment § 57.22311 Electrical cables (II-A mines). Only jacketed electrical cables accepted or approved by MSHA as flame resistant shall be used to supply power to... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Electrical cables (II-A mines). 57.22311...
High-performance, lightweight coaxial cable from carbon nanotube conductors.
Jarosz, Paul R; Shaukat, Aalyia; Schauerman, Christopher M; Cress, Cory D; Kladitis, Paul E; Ridgley, Richard D; Landi, Brian J
2012-02-01
Coaxial cables have been constructed with carbon nanotube (CNT) materials serving as both the inner and outer conductors. Treatment of the CNT outer and inner conductors with KAuBr(4) was found to significantly reduce the attenuation of these cables, which demonstrates that chemical agents can be used to improve power transmission through CNT networks at high frequencies (150 kHz-3 GHz). For cables constructed with a KAuBr(4)-treated CNT outer conductor, power attenuation per length approaches parity with cables constructed from metallic conductors at significantly lower weight per length (i.e., 7.1 g/m for CNT designs compared to 38.8 g/m for an RG-58 design). A relationship between the thickness of the CNT outer conductor and the cable attenuation was observed and used to estimate the effective skin depth at high frequency. These results establish reliable, reproducible methods for the construction of coaxial cables from CNT materials that can facilitate further investigation of their performance in high-frequency transmission structures, and highlight a specific opportunity for significant reduction in coaxial cable mass.
Assessment of the insulation degradation of cables used in nuclear power plants
NASA Astrophysics Data System (ADS)
Bartoníc̆ek, B.; Hnát, V.; Plac̆ek, V.
1999-05-01
Cable insulating materials are usually, during their operational lifetime, exposed to a high number of various deteriorative enviromental effects resulting in their degradation. In the case of cables used in the nuclear power plant (NPP) hermetic zone these factors consist predominantly of long-term irradiation (at rather low dose rates, in the presence of oxygen) and enhanced temperature. Hence, all cables assigned for use in NPP have to be qualified for use under such severe conditions. However, not only the initial qualification but also monitoring of the actual state of the installed cables in regular intervals is now recommended. Monitoring of the actual state of the cable insulation and the prediction of their residual service life (i.e., the on-going qualification) consist of the measurement of the properties that are directly proportional to the functionality of the cables (usually the elongation at break is used as the critical parameter). For the cables installed in the NPP hermetic zone a method based on the measurement of the thermo-oxidative stability by the differential scanning calorimetry has been developed.
Detection of incipient defects in cables by partial discharge signal analysis
NASA Astrophysics Data System (ADS)
Martzloff, F. D.; Simmon, E.; Steiner, J. P.; Vanbrunt, R. J.
1992-07-01
As one of the objectives of a program aimed at assessing test methods for in-situ detection of incipient defects in cables due to aging, a laboratory test system was implemented to demonstrate that the partial discharge analysis method can be successfully applied to low-voltage cables. Previous investigations generally involved cables rated 5 kV or higher, while the objective of the program focused on the lower voltages associated with the safety systems of nuclear power plants. The defect detection system implemented for the project was based on commercially available signal analysis hardware and software packages, customized for the specific purposes of the project. The test specimens included several cables of the type found in nuclear power plants, including artificial defects introduced at various points of the cable. The results indicate that indeed, partial discharge analysis is capable of detecting incipient defects in low-voltage cables. There are, however, some limitations of technical and non-technical nature that need further exploration before this method can be accepted in the industry.
Reusable Hot-Wire Cable Cutter
NASA Technical Reports Server (NTRS)
Pauken, Michael T.; Steinkraus, Joel M.
2010-01-01
During the early development stage of balloon deployment systems for missions, nichrome wire cable cutters were often used in place of pyro-actuated cutters. Typically, a nichrome wire is wrapped around a bundle of polymer cables with a low melting point and connected to a relay-actuated electric circuit. The heat from the nichrome reduces the strength of the cable bundle, which quickly breaks under a mechanical load and can thus be used as a release mechanism for a deployment system. However, the use of hand-made heated nichrome wire for cutters is not very reliable. Often, the wrapped nichrome wire does not cut through the cable because it either pulls away from its power source or does not stay in contact with the cable being cut. Because nichrome is not readily soldered to copper wire, unreliable mechanical crimps are often made to connect the nichrome to an electric circuit. A self-contained device that is reusable and reliable was developed to sever cables for device release or deployment. The nichrome wire in this new device is housed within an enclosure to prevent it from being damaged by handling. The electric power leads are internally connected within the unit to the nichrome wire using a screw terminal connection. A bayonet plug, a quick and secure method of connecting the cutter to the power source, is used to connect the cutter to the power leads similar to those used in pyro-cutter devices. A small ceramic tube [0.25-in. wide 0.5-in. long (.6.4-mm wide 13-mm long)] houses a spiraled nichrome wire that is heated when a cable release action is required. The wire is formed into a spiral coil by wrapping it around a mandrel. It is then laid inside the ceramic tube so that it fits closely to the inner surface of the tube. The ceramic tube provides some thermal and electrical insulation so that most of the heat generated by the wire is directed toward the cable bundle in the center of the spiral. The ceramic tube is cemented into an aluminum block, which holds it in position. The leads of the nichrome wire are attached to screw terminals that connect them to power leads. A bayonet plug mounted at the bottom of the rectangular block connects the power leads to a relay circuit. A thin aluminum shell encloses the entire structure, leaving access points to attach to the bayonet plug and to feed a cable into the cylinder. The access holes for the deployment cable are a smaller diameter than the nichrome coil to prevent the cable from coming in direct contact with the nichrome when loaded. It uses the same general method of severing a cable with a heated wire as was used previously, but implements it in such a way that it is more reliable and less prone to failure. It creates a mechanism to create repeatability that was nonexistent in the previous method.
Stochastic Modelling of Wireless Energy Transfer
NASA Technical Reports Server (NTRS)
Veilleux, Shaun; Almaghasilah, Ahmed; Abedi, Ali; Wilkerson, DeLisa
2017-01-01
This study investigates the efficiency of a new method of powering remote sensors by the means of wireless energy transfer. The increased use of sensors for data collection comes with the inherent cost of supplying power from sources such as power cables or batteries. Wireless energy transfer technology eliminates the need for power cables or periodic battery replacement. The time and cost of setting up or expanding a sensor network will be reduced while allowing sensors to be placed in areas where running power cables or battery replacement is not feasible. This paper models wireless channels for power and data separately. Smart scheduling for the data channel is proposed to avoid transmitting data on a noisy channel where the probability of data loss is high to improve power efficiency. Analytical models have been developed and verified using simulations.
Power systems for ocean regional cabled observatories
NASA Technical Reports Server (NTRS)
Kojima, Junichi; Asakawa, Kenichi; Howe, Bruce M.; Kirkham, Harold
2004-01-01
Development of power systems is the most challenging technical issue in the design of ocean regional cabled observatories. ARENA and NEPTUNE are two ocean regional cabled observatory networks with aims that are at least broadly similar. Yet the two designs are quite different in detail. This paper outlines the both systems and explores the reasons for the divergence of design, and shows that it arose because of differences in the priority of requirements.
Superconducting power transmission system development. Cable insulation development
NASA Astrophysics Data System (ADS)
1983-09-01
The development of an underground superconducting power transmission system which is economical and technically attractive to the utility industry is discussed. Suitable superconductors and dielectric insulation were developed. Cables several hundred feet long are tested under realistic conditions. Three operating runs of about 2 weeks duration each were accomplished. The 60 Hz steady state performance of the cables under rated conditions was explored. Over voltage endurance tests and emergency level current tests were performed.
A Novel Concept for the Rapid Deployment of Electric Power Cables. Phase 1.
1987-04-30
cable toward the tactical position that requires power. The approach effectively neutralisasl both man-made and naturally occurring deployment...guided system with a reputation for extreme accuracy, it is anticipated that the cable can be delivered to a user located within a 1000 foot range...thus readily available, because it is an effective and reliable weapon system. The system has been up-graded several times which indicates that its
CNN Newsroom Classroom Guides, October 1-31, 1996.
ERIC Educational Resources Information Center
Cable News Network, Atlanta, GA.
These classroom guides, designed to accompany the daily CNN (Cable News Network) Newsroom broadcasts for the month of October, provide program rundowns, suggestions for class activities and discussion, student handouts, and a list of related news terms. Topics include: the Middle East peace summit in Washington, DC, Israel's Netanyahu and…
78 FR 21082 - Airworthiness Directives; GROB-WERKE Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2013-04-09
... of proposed rulemaking (NPRM). SUMMARY: We propose to adopt a new airworthiness directive (AD) for... cable routing causing electrical shorting behind the left-hand (LH) cockpit instrument panel. We are... Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE., Washington, DC 20590...
NEMA wire and cable standards development programs
NASA Astrophysics Data System (ADS)
Baird, Robert W.
1994-01-01
The National Electrical Manufacturers Association (NEMA) is the nation's largest trade association for manufacturers of electrical equipment. Its member companies produce components, end-use equipment and systems for the generation, transmission, distribution, control and use of electricity. The wire and cable division is presented in 6 sections: building wire and cable, fabricated conductors, flexible cords, high performance wire and cable, magnet wire, and power and control cable. Participating companies are listed.
Response of Nuclear Power Plant Instrumentation Cables Exposed to Fire Conditions.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Muna, Alice Baca; LaFleur, Chris Bensdotter; Brooks, Dusty Marie
This report presents the results of instrumentation cable tests sponsored by the US Nuclear Regulatory Commission (NRC) Office of Nuclear Regulatory Research and performed at Sandia National Laboratories (SNL). The goal of the tests was to assess thermal and electrical response behavior under fire-exposure conditions for instrumentation cables and circuits. The test objective was to assess how severe radiant heating conditions surrounding an instrumentation cable affect current or voltage signals in an instrumentation circuit. A total of thirty-nine small-scale tests were conducted. Ten different instrumentation cables were tested, ranging from one conductor to eight-twisted pairs. Because the focus of themore » tests was thermoset (TS) cables, only two of the ten cables had thermoplastic (TP) insulation and jacket material and the remaining eight cables were one of three different TS insulation and jacket material. Two instrumentation cables from previous cable fire testing were included, one TS and one TP. Three test circuits were used to simulate instrumentation circuits present in nuclear power plants: a 4–20 mA current loop, a 10–50 mA current loop and a 1–5 VDC voltage loop. A regression analysis was conducted to determine key variables affecting signal leakage time.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Simmons, Kevin L.; Ramuhalli, Pradeep; Brenchley, David L.
2012-09-14
The purpose of the non-destructive evaluation (NDE) R&D Roadmap for Cables is to support the Materials Aging and Degradation (MAaD) R&D pathway. The focus of the workshop was to identify the technical gaps in detecting aging cables and predicting their remaining life expectancy. The workshop was held in Knoxville, Tennessee, on July 30, 2012, at Analysis and Measurement Services Corporation (AMS) headquarters. The workshop was attended by 30 experts in materials, electrical engineering, U.S. Nuclear Regulatory Commission (NRC), U.S. Department of Energy (DOE) National Laboratories (Oak Ridge National Laboratory, Pacific Northwest National Laboratory, Argonne National Laboratory, and Idaho National Engineeringmore » Laboratory), NDE instrumentation development, universities, commercial NDE services and cable manufacturers, and Electric Power Research Institute (EPRI). The motivation for the R&D roadmap comes from the need to address the aging management of in-containment cables at nuclear power plants (NPPs).« less
AC HTS Transmission Cable for Integration into the Future EHV Grid of the Netherlands
NASA Astrophysics Data System (ADS)
Zuijderduin, R.; Chevtchenko, O.; Smit, J. J.; Aanhaanen, G.; Melnik, I.; Geschiere, A.
Due to increasing power demand, the electricity grid of the Netherlands is changing. The future grid must be capable to transmit all the connected power. Power generation will be more decentralized like for instance wind parks connected to the grid. Furthermore, future large scale production units are expected to be installed near coastal regions. This creates some potential grid issues, such as: large power amounts to be transmitted to consumers from west to east and grid stability. High temperature superconductors (HTS) can help solving these grid problems. Advantages to integrate HTS components at Extra High Voltage (EHV) and High Voltage (HV) levels are numerous: more power with less losses and less emissions, intrinsic fault current limiting capability, better control of power flow, reduced footprint, etc. Today's main obstacle is the relatively high price of HTS. Nevertheless, as the price goes down, initial market penetration for several HTS components is expected by year 2015 (e.g.: cables, fault current limiters). In this paper we present a design of intrinsically compensated EHV HTS cable for future grid integration. Discussed are the parameters of such cable providing an optimal power transmission in the future network.
OTEC riser cable model and prototype testing
NASA Astrophysics Data System (ADS)
Kurt, J. P.; Schultz, J. A.; Roblee, L. H. S.
1981-12-01
Two different OTEC riser cables have been developed to span the distance between a floating OTEC power plant and the ocean floor. The major design concerns for a riser cable in the dynamic OTEC environment are fatigue, corrosion, and electrical/mechanical aging of the cable components. The basic properties of the cable materials were studied through tests on model cables and on samples of cable materials. Full-scale prototype cables were manufactured and were tested to measure their electrical and mechanical properties and performance. The full-scale testing was culminated by the electrical/mechanical fatigue test, which exposes full-scale cables to simultaneous tension, bending and electrical loads, all in a natural seawater environment.
King, Robert Dean; DeDoncker, Rik Wivina Anna Adelson
1998-01-01
A method and apparatus for load leveling of a battery in an electrical power system includes a power regulator coupled to transfer power between a load and a DC link, a battery coupled to the DC link through a first DC-to-DC converter and an auxiliary passive energy storage device coupled to the DC link through a second DC-to-DC converter. The battery is coupled to the passive energy storage device through a unidirectional conducting device whereby the battery can supply power to the DC link through each of the first and second converters when battery voltage exceeds voltage on the passive storage device. When the load comprises a motor capable of operating in a regenerative mode, the converters are adapted for transferring power to the battery and passive storage device. In this form, resistance can be coupled in circuit with the second DC-to-DC converter to dissipate excess regenerative power.
King, R.D.; DeDoncker, R.W.A.A.
1998-01-20
A method and apparatus for load leveling of a battery in an electrical power system includes a power regulator coupled to transfer power between a load and a DC link, a battery coupled to the DC link through a first DC-to-DC converter and an auxiliary passive energy storage device coupled to the DC link through a second DC-to-DC converter. The battery is coupled to the passive energy storage device through a unidirectional conducting device whereby the battery can supply power to the DC link through each of the first and second converters when battery voltage exceeds voltage on the passive storage device. When the load comprises a motor capable of operating in a regenerative mode, the converters are adapted for transferring power to the battery and passive storage device. In this form, resistance can be coupled in circuit with the second DC-to-DC converter to dissipate excess regenerative power. 8 figs.
NASA Astrophysics Data System (ADS)
Dobra, R.; Pasculescu, D.; Marc, G.; Risteiu, M.; Antonov, A.
2017-06-01
Insulation resistance measurement is one of the most important tests required by standards and regulations in terms of electrical safety. Why these tests are is to prevent possible accidents caused by electric shock, damage to equipment or outbreak of fire in normal operating conditions of electrical cables. The insulation resistance experiment refers to the testing of electrical cable insulation, which has a measured resistance that must be below the imposed regulations. Using a microcontroller system data regarding the insulation resistance of the power cables is acquired and with SCADA software the test results are displayed.
Development of a DC-DC conversion powering scheme for the CMS Phase-1 pixel upgrade
NASA Astrophysics Data System (ADS)
Feld, L.; Fimmers, C.; Karpinski, W.; Klein, K.; Lipinski, M.; Preuten, M.; Rauch, M.; Rittich, D.; Sammet, J.; Wlochal, M.
2014-01-01
A novel powering scheme based on the DC-DC conversion technique will be exploited to power the CMS Phase-1 pixel detector. DC-DC buck converters for the CMS pixel project have been developed, based on the AMIS5 ASIC designed by CERN. The powering system of the Phase-1 pixel detector is described and the performance of the converter prototypes is detailed, including power efficiency, stability of the output voltage, shielding, and thermal management. Results from a test of the magnetic field tolerance of the DC-DC converters are reported. System tests with pixel modules using many components of the future pixel barrel system are summarized. Finally first impressions from a pre-series of 200 DC-DC converters are presented.
Modelling ac ripple currents in HTS coated conductors
NASA Astrophysics Data System (ADS)
Xu, Zhihan; Grilli, Francesco
2015-10-01
Dc transmission using high temperature superconducting (HTS) coated conductors (CCs) offers a promising solution to the globally growing demand for effective, reliable and economic transmission of green energy up to the gigawatt level over very long distances. The credible estimation of the losses and thereby the heat dissipation involved, where ac ripples (introduced in rectification/ac-dc conversion) are viewed as a potential source of notable contribution, is highly essential for the rational design of practical HTS dc transmission cables and corresponding cryogenic systems to fulfil this demand. Here we report a targeted modelling study into the ac losses in a HTS CC subject to dc and ac ripple currents simultaneously, by solving Maxwell’s equations using the finite element method (FEM) in the commercial software package COMSOL. It is observed that the instantaneous loss exhibits only one peak per cycle in the HTS CC subject to sinusoidal ripples, given that the amplitude of the ac ripples is smaller than approximately 20% of that of the dc current. This is a distinct contrast to the usual observation of two peaks per cycle in a HTS CC subject to ac currents only. The unique mechanism is also revealed, which is directly associated with the finding that, around any local minima of the applied ac ripples, the critical state of -J c is never reached at the edges of the HTS CC, as it should be according to the Bean model. When running further into the longer term, it is discovered that the ac ripple loss of the HTS CC in full-wave rectification decays monotonically, at a speed which is found to be insensitive to the frequency of the applied ripples within our targeted situations, to a relatively low level of approximately 1.38 × 10-4 W m-1 in around 1.7 s. Comparison between this level and other typical loss contributions in a HTS dc cable implies that ac ripple currents in HTS CCs should only be considered as a minor source of dissipation in superconducting dc transmission.
NASA Astrophysics Data System (ADS)
Tian, Zhang; Yanfeng, Gong
2017-05-01
In order to solve the contradiction between demand and distribution range of primary energy resource, Ultra High Voltage (UHV) power grids should be developed rapidly to meet development of energy bases and accessing of large-scale renewable energy. This paper reviewed the latest research processes of AC/DC transmission technologies, summarized the characteristics of AC/DC power grids, concluded that China’s power grids certainly enter a new period of large -scale hybrid UHV AC/DC power grids and characteristics of “strong DC and weak AC” becomes increasingly pro minent; possible problems in operation of AC/DC power grids was discussed, and interaction or effect between AC/DC power grids was made an intensive study of; according to above problems in operation of power grids, preliminary scheme is summarized as fo llows: strengthening backbone structures, enhancing AC/DC transmission technologies, promoting protection measures of clean energ y accessing grids, and taking actions to solve stability problems of voltage and frequency etc. It’s valuable for making hybrid UHV AC/DC power grids adapt to operating mode of large power grids, thus guaranteeing security and stability of power system.
High-temperature flat-conductor cable
NASA Technical Reports Server (NTRS)
Rigling, W. S.
1976-01-01
Temperature limit of 25-conductor signal cable and 3-conductor power cable, fabricated using woven and roll laminated technique, increased from 200 C to 350 C when polyimide/fluorinated ethylene propylene or polytetrafluoroethylene insulation films and fluorinated ethylene propylene as adhesive medium is applied.
Electromagnetic-Pulse Handbook for Electric Power Systems
1975-02-04
penetratlor.s such as communications cables, antenna leads, etc.). (6) Avoid connecting the power neutral and external cable shields to the same point on the...prepared primarily for the power, communications , and systems engineer who must be concerned with the offects of the nuclear electromagnetic pulse on...INTRODUCTION Until a few years ago, the nuclear EMP community gave little attention to commer- cial power systems other than to recommend surge arrestors
Instrumentation Cables Test Plan
DOE Office of Scientific and Technical Information (OSTI.GOV)
Muna, Alice Baca; LaFleur, Chris Bensdotter
A fire at a nuclear power plant (NPP) has the potential to damage structures, systems, and components important to safety, if not promptly detected and suppressed. At Browns Ferry Nuclear Power Plant on March 22, 1975, a fire in the reactor building damaged electrical power and control systems. Damage to instrumentation cables impeded the function of both normal and standby reactor coolant systems, and degraded the operators’ plant monitoring capability. This event resulted in additional NRC involvement with utilities to ensure that NPPs are properly protected from fire as intended by the NRC principle design criteria (i.e., general design criteriamore » 3, Fire Protection). Current guidance and methods for both deterministic and performance based approaches typically make conservative (bounding) assumptions regarding the fire-induced failure modes of instrumentation cables and those failure modes effects on component and system response. Numerous fire testing programs have been conducted in the past to evaluate the failure modes and effects of electrical cables exposed to severe thermal conditions. However, that testing has primarily focused on control circuits with only a limited number of tests performed on instrumentation circuits. In 2001, the Nuclear Energy Institute (NEI) and the Electric Power Research Institute (EPRI) conducted a series of cable fire tests designed to address specific aspects of the cable failure and circuit fault issues of concern1. The NRC was invited to observe and participate in that program. The NRC sponsored Sandia National Laboratories to support this participation, whom among other things, added a 4-20 mA instrumentation circuit and instrumentation cabling to six of the tests. Although limited, one insight drawn from those instrumentation circuits tests was that the failure characteristics appeared to depend on the cable insulation material. The results showed that for thermoset insulated cables, the instrument reading tended to drift and fluctuate, while the thermoplastic insulated cables, the instrument reading fell off-scale rapidly. From an operational point of view, the latter failure characteristics would likely be identified as a failure from the effects of fire, while the former may result in inaccurate readings.« less
Hensman, C; Hanna, G B; Drew, T; Moseley, H; Cuschieri, A
1998-04-01
Skin burns and ignition of drapes have been reported with the use of cold light sources. The aim of the study was to document the temperature generated by cold light sources and to correlate this with the total radiated power and infrared output. The temperature, total radiated power, and infrared output were measured as a function of time at the end of the endoscope (which is inserted into the operative field) and the end of the fiber optic bundle of the light cable (which connects the cable to the light port of the endoscope) using halogen and xenon light sources. The highest temperature recorded at the end of the endoscope was 95 degrees C. The temperature measured at the optical fiber location of the endoscope was higher than at its lens surface (p < 0.0001). At the end of the fiber optic bundle of light cables, the temperature reached 225 degrees C within 15 s. The temperature recorded at the optical fiber location of all endoscopes and light cables studied rose significantly over a period of 10 min to reach its maximum (p <0.0001) and then leveled off for the duration of the study (30 min). The infrared output accounted only for 10% of the total radiated power. High temperatures are reached by 10 min at the end of fiber optic bundle of light cables and endoscopes with both halogen and xenon light sources. This heat generation is largely due to the radiated power in the visible light spectrum.
High power density dc/dc converter: Component selection and design
NASA Technical Reports Server (NTRS)
Divan, Deepakraj M.
1989-01-01
Further work pertaining to design considerations for the new high power, high frequency dc/dc converters is discussed. The goal of the project is the development of high power, high power density dc/dc converters at power levels in the multi-kilowatt to megawatt range for aerospace applications. The prototype converter is rated for 50 kW at a switching frequency of 50 kHz, with an input voltage of 200 Vdc and an output of 2000 Vdc. The overall power density must be in the vicinity of 0.2 to 0.3 kg/kW.
77 FR 19525 - Specification for 15 kV and 25 kV Primary Underground Power Cable
Federal Register 2010, 2011, 2012, 2013, 2014
2012-04-02
... has revised the final rule. Comment: Conductor Shield, NRECA T&D suggested adding (for discharge... be 3 through 18 pounds (1.36 through 8.16 kg) for EPR discharge free and TR-XLPE cables. Discharge....16 kg) for EPR discharge free and TR-XLPE cables. Discharge resistant cables shall have strip tension...
Dunham, A; Pegg, J R; Carolsfeld, W; Davies, S; Murfitt, I; Boutillier, J
2015-06-01
We examined the effects of submarine power transmission cable installation and operation on glass sponge reef condition and associated megafauna. Video and still imagery were collected using a Remotely Operated Vehicle twice a year for 4 years following cable installation. The effects of cables on glass sponges were assessed by comparing sponge cover along fixed transects and at marked index sites. Megafauna counts along transects were used to explore the effects on associated community. We found no evidence of cable movement across the sponge reef surface. Live sponge cover was found to be consistently lower along cable transects and at cable index sites compared to controls. Live sponge cover was the lowest (55 ± 1.1% decrease) at cable index sites 1.5 years after installation and recovered to 85 ± 30.6% of the original size over the following 2 years. Our data suggest 100% glass sponge mortality along the direct cable footprint and 15% mortality in the surrounding 1.5 m corridor 3.5 years after cable installation. Growth rate of a new glass sponge was 1 and 3 cm/year in first and second year, respectively, and appeared to be seasonal. We observed a diverse megafaunal community with representatives from 7 phyla and 14 classes. Total megafauna, spot prawn, and other Arthropoda abundances were slightly lower along cable transects although the effect of cable presence was not statistically significant. The following measures could be taken to reduce the amount of damage to glass sponge reefs and associated fauna: routing the cable around reefs, whenever possible, minimizing cable movement across the surface of the reef at installation and routine operation, and assessing potential damage to glass sponges prior to decommissioning. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.
A solid state converter for measurement of aircraft noise and sonic boom
NASA Technical Reports Server (NTRS)
Zuckerwar, A. J.
1972-01-01
The problems inherent in present systems of instrumentation for measuring aircraft noise and sonic boom include limited frequency response, expensive connecting cables, sensitivity to cable length and type, high sensitivity to environmental conditions, and additional limitations of individual system components. Furthermore, differing requirements have resulted in the use of two different systems for aircraft noise and sonic boom measurements respectively. To alleviate these difficulties a unified system of instrumentation suitable for both types of measurements was developed. The system features a new solid state converter connected to a zero drive amplifier. The system was found insensitive to cable length and type up to at least 1000 ft and requires no impedance matching networks. The converter itself has flat frequency response from dc to 28 kHz (- 3 db), dynamic range of 72 db, and noise floor of 50 db in the band 22.4 Hz to 22.4 kHz.
Transient sheath overvoltages in armored power cables
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gustavsen, B.; Sletbak, J.
1996-07-01
This paper is concerned with methods of limiting the build-up of transient voltages between sheath and armor in long armored power cables. Calculations by a frequency dependent cable model demonstrate that this voltage can be efficiently limited to an acceptable level by introducing sheath-armor bondings at regular intervals, or by using a semiconductive sheath-armor interlayer. The paper investigates the required minimum length between bondings, as well as the required conductivity of the sheath-armor interlayer if the use of bondings is to be avoided.
Horizontal cryogenic bushing for the termination of a superconducting power-transmission line
Minati, K.F.; Morgan, G.H.; McNerney, A.J.; Schauer, F.
1982-07-29
A termination for a superconducting power transmission line is disclosed which is comprised of a standard air entrance insulated vertical bushing with an elbow, a horizontal cryogenic bushing linking the pressurized cryogenic cable environment to the ambient temperature bushing and a stress cone which terminated the cable outer shield and transforms the large radial voltage gradient in the cable dielectric into a much lower radial voltage gradient in the high density helium coolant at the cold end of the cryogenic bushing.
Termination for a superconducting power transmission line including a horizontal cryogenic bushing
Minati, Kurt F.; Morgan, Gerry H.; McNerney, Andrew J.; Schauer, Felix
1984-01-01
A termination for a superconducting power transmission line is disclosed which is comprised of a standard air entrance insulated vertical bushing with an elbow, a horizontal cryogenic bushing linking the pressurized cryogenic cable environment to the ambient temperature bushing and a stress cone which terminates the cable outer shield and transforms the large radial voltage gradient in the cable dielectric into a much lower radial voltage gradient in the high density helium coolant at the cold end of the cryogenic bushing.
FireFly: reconfigurable optical wireless networking data centers
NASA Astrophysics Data System (ADS)
Kavehrad, Mohsen; Deng, Peng; Gupta, H.; Longtin, J.; Das, S. R.; Sekar, V.
2017-01-01
We explore a novel, free-space optics based approach for building data center interconnects. Data centers (DCs) are a critical piece of today's networked applications in both private and public sectors. The key factors that have driven this trend are economies of scale, reduced management costs, better utilization of hardware via statistical multiplexing, and the ability to elastically scale applications in response to changing workload patterns. A robust DC network fabric is fundamental to the success of DCs and to ensure that the network does not become a bottleneck for high-performance applications. In this context, DC network design must satisfy several goals: high performance (e.g., high throughput and low latency), low equipment and management cost, robustness to dynamic traffic patterns, incremental expandability to add new servers or racks, and other practical concerns such as cabling complexity, and power and cooling costs. Current DC network architectures do not seem to provide a satisfactory solution, with respect to the above requirements. In particular, traditional static (wired) networks are either overprovisioned or oversubscribed. Recent works have tried to overcome the above limitations by augmenting a static (wired) "core" with some flexible links (RF-wireless or optical). These augmented architectures show promise, but offer only incremental improvement in performance. Specifically, RFwireless based augmented solutions also offer only limited performance improvement, due to inherent interference and range constraints of RF links. This paper explores an alternative design point—a fully flexible and all-wireless DC interrack network based on free-space optical (FSO) links. We call this FireFly as in; Free-space optical Inter-Rack nEtwork with high FLexibilitY. We will present our designs and tests using various configurations that can help the performance and reliability of the FSO links.
Design and development of 500 m long HTS cable system in the KEPCO power grid, Korea
NASA Astrophysics Data System (ADS)
Sohn, S. H.; Lim, J. H.; Yang, B. M.; Lee, S. K.; Jang, H. M.; Kim, Y. H.; Yang, H. S.; Kim, D. L.; Kim, H. R.; Yim, S. W.; Won, Y. J.; Hwang, S. D.
2010-11-01
In Korea, two long-term field demonstrations for high temperature superconducting (HTS) cable have been carried out for several years; Korea Electric Power Corporation (KEPCO) and LS Cable Ltd. (LSC) independently. Encouraged at the result of the projects performed in parallel, a new project targeting the real grid operation was launched in the fourth quarter of 2008 with the Korean government's financial support. KEPCO and LSC are jointly collaborating in the selection of substation, determination of cable specification, design of cryogenic system, and the scheme of protection coordination. A three phase 500 m long HTS cable at a distribution level voltage of 22.9 kV is to be built at 154/22.9 kV Icheon substation located in near Seoul. A hybrid cryogenic system reflecting the contingency plan is being designed including cryocoolers. The HTS cable system will be installed in the second quarter of 2010, being commissioned by the fall of 2010. This paper describes the objectives of the project and design issues of the cable and cryogenic system in detail.
76 FR 22733 - Cable Statutory License: Specialty Station List
Federal Register 2010, 2011, 2012, 2013, 2014
2011-04-22
... Counsel, Copyright GC/I&R, P.O. Box 70400, Southwest Station, Washington, DC 20024. Telephone: (202) 707... foreign- language, religious, and/or automated programming in one-third of the hours of an average... programming comports with the 1981 FCC definition, and hence, qualifies it as a specialty station. 55 FR 40021...
76 FR 69288 - Cable Statutory License: Specialty Station List
Federal Register 2010, 2011, 2012, 2013, 2014
2011-11-08
..., Copyright GC/I&R, P.O. Box 70400, Southwest Station, Washington, DC 20024. Telephone: (202) 707-8380... generally carries foreign-language, religious, and/or automated programming in one-third of the hours of an... the station to file an affidavit with the Office attesting to the fact that the station's programming...
Modular Seafloor and Water Column Systems for the Ocean Observatories Initiative Cabled Array
NASA Astrophysics Data System (ADS)
Delaney, J. R.; Manalang, D.; Harrington, M.; Tilley, J.; Dosher, J.; Cram, G.; Harkins, G.; McGuire, C.; Waite, P.; McRae, E.; McGinnis, T.; Kenney, M.; Siani, C.; Michel-Hart, N.; Denny, S.; Boget, E.; Kawka, O. E.; Daly, K. L.; Luther, D. S.; Kelley, D. S.; Milcic, M.
2016-02-01
Over the past decade, cabled ocean observatories have become an increasingly important way to collect continuous real-time data at remote subsea locations. This has led to the development of a class of subsea systems designed and built specifically to distribute power and bandwidth among sensing instrumentation on the seafloor and throughout the water column. Such systems are typically powered by shore-based infrastructure and involve networks of fiber optic and electrical cabling that provide real-time data access and control of remotely deployed instrumentation. Several subsea node types were developed and/or adapted for cabled use in order to complete the installation of the largest North American scientific cabled observatory in Oct, 2014. The Ocean Observatories Initiative (OOI) Cabled Array, funded by the US National Science Foundation, consists of a core infrastructure that includes 900 km of fiber optic/electrical cables, seven primary nodes, 18 seafloor junction boxes, three mooring-mounted winched profiling systems, and three wire-crawling profiler systems. In aggregate, the installed infrastructure has 200 dedicated scientific instrument ports (of which 120 are currently assigned), and is capable of further expansion. The installed system has a 25-year design life for reliable, sustained monitoring; and all nodes, profilers and instrument packages are ROV-serviceable. Now in it's second year of operation, the systems that comprise the Cabled Array are providing reliable, 24/7 real-time data collection from deployed instrumentation, and offer a modular and scalable class of subsea systems for ocean observing. This presentation will provide an overview of the observatory-class subsystems of the OOI Cabled Array, focusing on the junction boxes, moorings and profilers that power and communicate with deployed instrumentation.
LeBlanc, M
1990-01-01
Present body-powered upper-limb prostheses use a cable control system employing World War II aircraft technology to transmit force from the body to the prosthesis for operation. The cable and associated hardware are located outside the prosthesis. Because individuals with arm amputations want prostheses that are natural looking with a smooth, soft outer surface, a design and development project was undertaken to replace the cable system with hydraulics located inside the prosthesis. Three different hydraulic transmission systems were built for evaluation, and other possibilities were explored. Results indicate that a hydraulic force transmission system remains an unmet challenge as a practical replacement for the cable system. The author was unable to develop a hydraulic system that meets the necessary dynamic requirements and is acceptable in size and appearance.
Research on DC Micro-grid system of photovoltaic power generation
NASA Astrophysics Data System (ADS)
Zheng, Yiming; Wang, Xiaohui
2018-01-01
The use of energy has become a topic of concern, the demand of people for power grows in number or quantity with the development of economy. It is necessary to consider using new forms of power supply-microgrid system for distributed power supply. The power supply mode can not only effectively solve the problem of excessive line loss in the large power grid, but also can increase the reliability of the power supply, and is economical and environmental friendly. With the increasing of DC loads, in order to improve the utilization efficiency, the DC microgrid power supply problems are begin to be researched and integrated with the renewable energy sources. This paper researched the development of microgrid, compared AC microgrid with DC microgrid, summarized the distribution of DC bus voltage level, the DC microgrid network form, the control mode and the main power electronics elements of DC microgrid of photovoltaic power generation system. Today, the DC microgrid system is still in the development stage without uniform voltage level standard, however, it will come into service in the future.
30 CFR 56.12014 - Handling energized power cables.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Handling energized power cables. 56.12014 Section 56.12014 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity...
30 CFR 56.12014 - Handling energized power cables.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Handling energized power cables. 56.12014 Section 56.12014 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity...
30 CFR 56.12014 - Handling energized power cables.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Handling energized power cables. 56.12014 Section 56.12014 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity...
30 CFR 56.12014 - Handling energized power cables.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Handling energized power cables. 56.12014 Section 56.12014 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity...
30 CFR 56.12014 - Handling energized power cables.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Handling energized power cables. 56.12014 Section 56.12014 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity...
Simultaneous distribution of AC and DC power
Polese, Luigi Gentile
2015-09-15
A system and method for the transport and distribution of both AC (alternating current) power and DC (direct current) power over wiring infrastructure normally used for distributing AC power only, for example, residential and/or commercial buildings' electrical wires is disclosed and taught. The system and method permits the combining of AC and DC power sources and the simultaneous distribution of the resulting power over the same wiring. At the utilization site a complementary device permits the separation of the DC power from the AC power and their reconstruction, for use in conventional AC-only and DC-only devices.
An algorithm for power line detection and warning based on a millimeter-wave radar video.
Ma, Qirong; Goshi, Darren S; Shih, Yi-Chi; Sun, Ming-Ting
2011-12-01
Power-line-strike accident is a major safety threat for low-flying aircrafts such as helicopters, thus an automatic warning system to power lines is highly desirable. In this paper we propose an algorithm for detecting power lines from radar videos from an active millimeter-wave sensor. Hough Transform is employed to detect candidate lines. The major challenge is that the radar videos are very noisy due to ground return. The noise points could fall on the same line which results in signal peaks after Hough Transform similar to the actual cable lines. To differentiate the cable lines from the noise lines, we train a Support Vector Machine to perform the classification. We exploit the Bragg pattern, which is due to the diffraction of electromagnetic wave on the periodic surface of power lines. We propose a set of features to represent the Bragg pattern for the classifier. We also propose a slice-processing algorithm which supports parallel processing, and improves the detection of cables in a cluttered background. Lastly, an adaptive algorithm is proposed to integrate the detection results from individual frames into a reliable video detection decision, in which temporal correlation of the cable pattern across frames is used to make the detection more robust. Extensive experiments with real-world data validated the effectiveness of our cable detection algorithm. © 2011 IEEE
NASA Astrophysics Data System (ADS)
Baranov, M. I.; Rudakov, S. V.
2018-03-01
The authors have given results of investigations of the electrothermal action of aperiodic pulses of temporal shape 10/350 μs of the current of a short artificial-lightning stroke on test specimens of electric wires and cables with copper and aluminum cores and sheaths with polyvinylchloride and polyethylene insulations of power circuits of industrial electric power objects. It has been shown that the thermal stability of such wires and cables is determined by the action integral of the indicated current pulse. The authors have found the maximum permissible and critical densities of this pulse in copper and aluminum current-carrying parts of the wires and cables. High-current experiments conducted under high-voltage laboratory conditions on a unique generator of 10/350 μs pulses of an artificial-lightning current with amplitude-time parameters normalized according to the existing requirements of international and national standards and with tolerances on them have confirmed the reliability of the proposed calculated estimate for thermal lightning resistance of cabling and wiring products.
NASA Astrophysics Data System (ADS)
Baranov, M. I.; Rudakov, S. V.
2018-05-01
The authors have given results of investigations of the electrothermal action of aperiodic pulses of temporal shape 10/350 μs of the current of a short artificial-lightning stroke on test specimens of electric wires and cables with copper and aluminum cores and sheaths with polyvinylchloride and polyethylene insulations of power circuits of industrial electric power objects. It has been shown that the thermal stability of such wires and cables is determined by the action integral of the indicated current pulse. The authors have found the maximum permissible and critical densities of this pulse in copper and aluminum current-carrying parts of the wires and cables. High-current experiments conducted under high-voltage laboratory conditions on a unique generator of 10/350 μs pulses of an artificial-lightning current with amplitude-time parameters normalized according to the existing requirements of international and national standards and with tolerances on them have confirmed the reliability of the proposed calculated estimate for thermal lightning resistance of cabling and wiring products.
Electrical cable utilization for wave energy converters
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bull, Diana; Baca, Michael; Schenkman, Benjamin
Here, this paper investigates the suitability of sizing the electrical export cable based on the rating of the contributing WECs within a farm. These investigations have produced a new methodology to evaluate the probabilities associated with peak power values on an annual basis. It has been shown that the peaks in pneumatic power production will follow an exponential probability function for a linear model. A methodology to combine all the individual probability functions into an annual view has been demonstrated on pneumatic power production by a Backward Bent Duct Buoy (BBDB). These investigations have also resulted in a highly simplifiedmore » and perfunctory model of installed cable cost as a function of voltage and conductor cross-section. This work solidifies the need to determine electrical export cable rating based on expected energy delivery as opposed to device rating as small decreases in energy delivery can result in cost savings.« less
Electrical cable utilization for wave energy converters
Bull, Diana; Baca, Michael; Schenkman, Benjamin
2018-04-27
Here, this paper investigates the suitability of sizing the electrical export cable based on the rating of the contributing WECs within a farm. These investigations have produced a new methodology to evaluate the probabilities associated with peak power values on an annual basis. It has been shown that the peaks in pneumatic power production will follow an exponential probability function for a linear model. A methodology to combine all the individual probability functions into an annual view has been demonstrated on pneumatic power production by a Backward Bent Duct Buoy (BBDB). These investigations have also resulted in a highly simplifiedmore » and perfunctory model of installed cable cost as a function of voltage and conductor cross-section. This work solidifies the need to determine electrical export cable rating based on expected energy delivery as opposed to device rating as small decreases in energy delivery can result in cost savings.« less
New Opportunities for Cabled Ocean Observatories
NASA Astrophysics Data System (ADS)
Duennebier, F. K.; Butler, R.; Karl, D. M.; Roger, L. B.
2002-12-01
With the decommissioning of transoceanic telecommunications cables as they become obsolete or uneconomical, there is an opportunity to use these systems for ocean observatories. Two coaxial cables, TPC-1 and HAW-2 are currently in use for observatories, and another, ANZCAN, is scheduled to be used beginning in 2004 to provide a cabled observatory at Station ALOHA, north of Oahu. The ALOHA observatory will provide several Mb/s data rates and about 1 kW of power to experiments installed at Station ALOHA. Sensors can be installed either by wet mateable connection to a junction box on the ocean floor using an ROV, or by acoustic data link to the system. In either case real-time data will be provided to users over the Internet. A Small Experiment Module, to be first installed at the Hawaii-2 Observatory, and later at Station ALOHA, will provide relatively cheap and uncomplicated access to the observatories for relatively simple sensors. Within the next few years, the first electro-optical cables installed in the 1980's will be decommissioned and could be available for scientific use. These cables could provide long "extension cords" (thousands of km) with very high bandwidth and reasonable power to several observatories in remote locations in the ocean. While they could be used in-place, a more exciting scenario is to use cable ships to pick up sections of cable and move them to locations of higher scientific interest. While such moves would not be cheap, the costs would rival the cost of installation and maintenance of a buoyed observatory, with far more bandwidth and power available for science use.
Apparatus including a plurality of spaced transformers for locating short circuits in cables
NASA Technical Reports Server (NTRS)
Cason, R. L.; Mcstay, J. J. (Inventor)
1978-01-01
A cable fault locator is described for sensing faults such as short circuits in power cables. The apparatus includes a plurality of current transformers strategically located along a cable. Trigger circuits are connected to each of the current transformers for placing a resistor in series with a resistive element responsive to an abnormally high current flowing through that portion of the cable. By measuring the voltage drop across the resistive element, the location of the fault can be determined.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fifield, Leonard S.
Harvested cables from operating or decommissioned nuclear power plants present an important opportunity to validate models, understanding material aging behavior, and validate characterization techniques. Crystal River Unit 3 Nuclear Generating Plant is a pressurized water reactor that was licensed to operate from 1976 to 2013. Cable segments were harvested and made available to the Light Water Reactor Sustainability research program through the Electric Power Research Institute. Information on the locations and circuits within the reactor from whence the cable segments came, cable construction, sourcing and installation information, and photographs of the cable locations prior to harvesting were provided. The cablemore » variations provided represent six of the ten most common cable insulations in the nuclear industry and experienced service usage for periods from 15 to 42 years. Subsequently, these cables constitute a valuable asset for research to understand aging behavior and measurement of nuclear cables. Received cables harvested from Crystal River Unit 3 Nuclear Generating Plant consist of low voltage, insulated conductor surrounded by jackets in lengths from 24 to 100 feet each. Cable materials will primarily be used to investigate aging under simultaneous thermal and gamma radiation exposure. Each cable insulation and jacket material will be characterized in its as-received condition, including determination of the temperatures associated with endothermic transitions in the material using differential scanning calorimetry and dynamic mechanical analysis. Temperatures for additional thermal exposure aging will be selected following the thermal analysis to avoid transitions in accelerated laboratory aging that do not occur in field conditions. Aging temperatures above thermal transitions may also be targeted to investigate the potential for artifacts in lifetime prediction from rapid accelerated aging. Total gamma doses and dose rates targeted for each material will be determined based on filling gaps in prior work, known limits of material classes and resource constraints. Experimental plans will be developed in the context of existing data for the insulation and jacket materials available in published Department of Energy and Electric Power Research Institute reports toward addressing identified knowledge gaps.« less
30 CFR 56.12013 - Splices and repairs of power cables.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Splices and repairs of power cables. 56.12013 Section 56.12013 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity...
30 CFR 56.12013 - Splices and repairs of power cables.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Splices and repairs of power cables. 56.12013 Section 56.12013 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity...
30 CFR 56.12013 - Splices and repairs of power cables.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Splices and repairs of power cables. 56.12013 Section 56.12013 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity...
30 CFR 56.12013 - Splices and repairs of power cables.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Splices and repairs of power cables. 56.12013 Section 56.12013 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity...
30 CFR 56.12013 - Splices and repairs of power cables.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Splices and repairs of power cables. 56.12013 Section 56.12013 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity...
47 CFR 27.1202 - Cable/BRS cross-ownership.
Code of Federal Regulations, 2010 CFR
2010-10-01
... MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES Broadband Radio Service and Educational Broadband Service § 27... modifications, assignments or transfers of control by cable operators of BRS stations shall include a showing... who holds or shares the power to vote such stock, to any person who has the sole power to sell such...
77 FR 13191 - Airworthiness Directives; Bombardier, Inc. Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2012-03-06
... corrosion and inadequate silver-plating. This AD requires replacing ADG power feeder cables. We are issuing this AD to prevent galvanic corrosion on ADG power feeder cables, which could result in damage to the... damaged due to galvanic corrosion. It was subsequently determined that the silver- plating is inadequate...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sobral, S.T.; Barbosa, J.O.; Numes, J.V.C.
1988-10-01
This paper shows some special ground potential rise characteristics of substations fed by power cables. These characteristics were detected during the study of the interconnected ground system of 14 step-down urban substations fed by the 138 kV underground cable network serving the South Zone of Rio de Janeiro city in Brazil. As this type of system is very common in large cities, the subject can be of general interest for the industry. It was verified that when a fault occurs at a ''cable substation'' (a substation fed exclusively by power cables), almost no ground potential effects were detected at themore » faulted substation or at the other ''cable substations'' of the 138 kV network. However, high values of ground potential occurred at the ''transition substations'' (substations in which the power cables are connected to overhead 138 kV transmission lines, with steel groundwires). That ground potential was enough to produce shocks and equipment damage in certain ''transition substations''. It was verified that this problem has no relation with potential transfer. The paper shows also that the utilization of overhead lines with ACSR groundwires on the initial spans closer to the ''transition substation'' would be enough to avoid the problem. Even if the ACSR conductor is used only at the initial section of one of the lines, a reduction of the problem would be obtained. The paper shows also that the utilization of ACSR ground-wires near the ''transition substations'' contributes to reduce the amount of the copper necessary to control step, touch and mess potentials in these substations. Additional mitigation procedures are also examined in the paper.« less
NASA Technical Reports Server (NTRS)
Sander, W. A., III
1973-01-01
Dc to dc static power conditioning systems on unmanned spacecraft have as their inputs highly fluctuating dc voltages which they condition to regulated dc voltages. These input voltages may be less than or greater than the desired regulated voltages. The design of two circuits which address specific problems in the design of these power conditioning systems and a nonlinear analysis of one of the circuits are discussed. The first circuit design is for a nondissipative active ripple filter which uses an operational amplifier to amplify and cancel the sensed ripple voltage. A dc to dc converter operating at a switching frequency of 1 MHz is the second circuit discussed. A nonlinear analysis of the type of dc to dc converter utilized in designing the 1 MHz converter is included.
Cable Television and the University.
ERIC Educational Resources Information Center
Lyman, Richard
Universities contain powerful blocs of resistance to new educational technology, perhaps especially to television. University attitudes and structures as well as faculty ignorance, apathy, and resistance affect the development of cable television. No one seems to speak with great confidence and precision about the educational potential of cable.…
46 CFR 129.340 - Cable and wiring.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 46 Shipping 4 2010-10-01 2010-10-01 false Cable and wiring. 129.340 Section 129.340 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OFFSHORE SUPPLY VESSELS ELECTRICAL INSTALLATIONS Power Sources and Distribution Systems § 129.340 Cable and wiring. (a) If individual wires, rather than...
Early Oscillation Detection for DC/DC Converter Fault Diagnosis
NASA Technical Reports Server (NTRS)
Wang, Bright L.
2011-01-01
The electrical power system of a spacecraft plays a very critical role for space mission success. Such a modern power system may contain numerous hybrid DC/DC converters both inside the power system electronics (PSE) units and onboard most of the flight electronics modules. One of the faulty conditions for DC/DC converter that poses serious threats to mission safety is the random occurrence of oscillation related to inherent instability characteristics of the DC/DC converters and design deficiency of the power systems. To ensure the highest reliability of the power system, oscillations in any form shall be promptly detected during part level testing, system integration tests, flight health monitoring, and on-board fault diagnosis. The popular gain/phase margin analysis method is capable of predicting stability levels of DC/DC converters, but it is limited only to verification of designs and to part-level testing on some of the models. This method has to inject noise signals into the control loop circuitry as required, thus, interrupts the DC/DC converter's normal operation and increases risks of degrading and damaging the flight unit. A novel technique to detect oscillations at early stage for flight hybrid DC/DC converters was developed.
Performance of Power Converters at Cryogenic Temperatures
NASA Technical Reports Server (NTRS)
Elbuluk, Malik E.; Gerber, Scott; Hammoud, Ahmad; Patterson, Richard L.
2001-01-01
Power converters capable of operation at cryogenic temperatures are anticipated to play an important role in the power system architecture of future NASA deep space missions. Design of such converters to survive cryogenic temperatures will improve the power system performance and reduce development and launch costs. Aerospace power systems are mainly a DC distribution network. Therefore, DC/DC and DC/AC converters provide the outputs needed to different loads at various power levels. Recently, research efforts have been performed at the NASA Glenn Research Center (GRC) to design and evaluate DC/DC converters that are capable of operating at cryogenic temperatures. This paper presents a summary of the research performed to evaluate the low temperature performance of five DC/DC converters. Various parameters were investigated as a function of temperature in the range of 20 to -196 C. Data pertaining to the output voltage regulation and efficiency of the converters is presented and discussed.
Development of a PLC modem for data transmission over a PWM power supply
NASA Astrophysics Data System (ADS)
Batard, Christophe; Ginot, Nicolas; Mannah, Marc Anthony; Millet, Christophe; Poitiers, Frédéric
2014-04-01
In variable-speed electrical drive and online conditioning monitoring, a feedback loop is required in order to transmit the sensor information from the motor to the controller close to the inverter. Additional cabling is used for signalling. This extra cabling has a significant cost and data transmission may not be reliable. Thus, the use of power line communication (PLC) technology to transmit data in motor drive application is quite interesting. The use of a PLC modem dedicated to the home network in a three-phase inverter-fed motor power cable does not work. Therefore, specific coupling interfaces are developed to transmit data through a pulse-width modulated power supply. Laboratory tests have shown that the couplers are operating properly. They ensure reliable data transmission in a motor drive application.
Ferrite core coupled slapper detonator apparatus and method
Boberg, Ralph E.; Lee, Ronald S.; Weingart, Richard C.
1989-01-01
Method and apparatus are provided for coupling a temporally short electric power pulse from a thick flat-conductor power cable into a thin flat-conductor slapper detonator circuit. A first planar and generally circular loop is formed from an end portion of the power cable. A second planar and generally circular loop, of similar diameter, is formed from all or part of the slapper detonator circuit. The two loops are placed together, within a ferrite housing that provides a ferrite path that magnetically couples the two loops. Slapper detonator parts may be incorporated within the ferrite housing. The ferrite housing may be made vacuum and water-tight, with the addition of a hermetic ceramic seal, and provided with an enclosure for protecting the power cable and parts related thereto.
Ferrite core coupled slapper detonator apparatus and method
Boberg, R.E.; Lee, R.S.; Weingart, R.C.
1989-08-01
Method and apparatus are provided for coupling a temporally short electric power pulse from a thick flat-conductor power cable into a thin flat-conductor slapper detonator circuit. A first planar and generally circular loop is formed from an end portion of the power cable. A second planar and generally circular loop, of similar diameter, is formed from all or part of the slapper detonator circuit. The two loops are placed together, within a ferrite housing that provides a ferrite path that magnetically couples the two loops. Slapper detonator parts may be incorporated within the ferrite housing. The ferrite housing may be made vacuum and water-tight, with the addition of a hermetic ceramic seal, and provided with an enclosure for protecting the power cable and parts related thereto. 10 figs.
Triple voltage dc-to-dc converter and method
Su, Gui-Jia
2008-08-05
A circuit and method of providing three dc voltage buses and transforming power between a low voltage dc converter and a high voltage dc converter, by coupling a primary dc power circuit and a secondary dc power circuit through an isolation transformer; providing the gating signals to power semiconductor switches in the primary and secondary circuits to control power flow between the primary and secondary circuits and by controlling a phase shift between the primary voltage and the secondary voltage. The primary dc power circuit and the secondary dc power circuit each further comprising at least two tank capacitances arranged in series as a tank leg, at least two resonant switching devices arranged in series with each other and arranged in parallel with the tank leg, and at least one voltage source arranged in parallel with the tank leg and the resonant switching devices, said resonant switching devices including power semiconductor switches that are operated by gating signals. Additional embodiments having a center-tapped battery on the low voltage side and a plurality of modules on both the low voltage side and the high voltage side are also disclosed for the purpose of reducing ripple current and for reducing the size of the components.
Evaluation of Information Leakage from Cryptographic Hardware via Common-Mode Current
NASA Astrophysics Data System (ADS)
Hayashi, Yu-Ichi; Homma, Naofumi; Mizuki, Takaaki; Sugawara, Takeshi; Kayano, Yoshiki; Aoki, Takafumi; Minegishi, Shigeki; Satoh, Akashi; Sone, Hideaki; Inoue, Hiroshi
This paper presents a possibility of Electromagnetic (EM) analysis against cryptographic modules outside their security boundaries. The mechanism behind the information leakage is explained from the view point of Electromagnetic Compatibility: electric fluctuation released from cryptographic modules can conduct to peripheral circuits based on ground bounce, resulting in radiation. We demonstrate the consequence of the mechanism through experiments where the ISO/IEC standard block cipher AES (Advanced Encryption Standard) is implemented on an FPGA board and EM radiations from power and communication cables are measured. Correlation Electromagnetic Analysis (CEMA) is conducted in order to evaluate the information leakage. The experimental results show that secret keys are revealed even though there are various disturbing factors such as voltage regulators and AC/DC converters between the target module and the measurement points. We also discuss information-suppression techniques as electrical-level countermeasures against such CEMAs.
NASA Astrophysics Data System (ADS)
Lightstone, P. C.; Davidson, W. M.
1982-04-01
The military detection assessment laboratory houses an experimental field system which assesses different alarm indicators such as fence disturbance sensors, MILES cables, and microwave Racons. A speech synthesis board which could be interfaced, by means of a computer, to an alarm logger making verbal acknowledgement of alarms possible was purchased. Different products and different types of voice synthesis were analyzed before a linear predictive code device produced by Telesensory Speech Systems of Palo Alto, California was chosen. This device is called the Speech 1000 Board and has a dedicated 8085 processor. A multiplexer card was designed and the Sp 1000 interfaced through the card into a TMS 990/100M Texas Instrument microcomputer. It was also necessary to design the software with the capability of recognizing and flagging an alarm on any 1 of 32 possible lines. The experimental field system was then packaged with a dc power supply, LED indicators, speakers, and switches, and deployed in the field performing reliably.
Electrical aging markers for EPR-based low-voltage cable insulation wiring of nuclear power plants
NASA Astrophysics Data System (ADS)
Verardi, L.; Fabiani, D.; Montanari, G. C.
2014-01-01
This paper presents results of electrical property measurements on EPR-based insulations of low-voltage power cables used in nuclear power plants. The specimens underwent accelerated aging through the simultaneous application of high temperature and gamma-radiation. Mechanical properties and the dielectric response at different frequencies were investigated. Results showed significant variation of the electrical and mechanical properties of aged cables at low frequencies, i.e. lower than 10-2 Hz. In particular, the real and imaginary parts of permittivity increase with aging time, accumulated dose and stress levels applied showing good correlation with elongation at break, which decreases as a function of extent of insulation aging.
30 CFR 57.22310 - Electrical cables (I-C mines).
Code of Federal Regulations, 2013 CFR
2013-07-01
... Standards for Methane in Metal and Nonmetal Mines Equipment § 57.22310 Electrical cables (I-C mines). Electrical cables used to power submersible sump pumps shall be accepted or approved by MSHA as flame... be sealed to prevent entry of explosive gas or dust. [57 FR 61223, Dec. 23, 1992] ...
30 CFR 57.22310 - Electrical cables (I-C mines).
Code of Federal Regulations, 2014 CFR
2014-07-01
... Standards for Methane in Metal and Nonmetal Mines Equipment § 57.22310 Electrical cables (I-C mines). Electrical cables used to power submersible sump pumps shall be accepted or approved by MSHA as flame... be sealed to prevent entry of explosive gas or dust. [57 FR 61223, Dec. 23, 1992] ...
30 CFR 57.22310 - Electrical cables (I-C mines).
Code of Federal Regulations, 2012 CFR
2012-07-01
... Standards for Methane in Metal and Nonmetal Mines Equipment § 57.22310 Electrical cables (I-C mines). Electrical cables used to power submersible sump pumps shall be accepted or approved by MSHA as flame... be sealed to prevent entry of explosive gas or dust. [57 FR 61223, Dec. 23, 1992] ...
30 CFR 57.22310 - Electrical cables (I-C mines).
Code of Federal Regulations, 2011 CFR
2011-07-01
... Standards for Methane in Metal and Nonmetal Mines Equipment § 57.22310 Electrical cables (I-C mines). Electrical cables used to power submersible sump pumps shall be accepted or approved by MSHA as flame... be sealed to prevent entry of explosive gas or dust. [57 FR 61223, Dec. 23, 1992] ...
30 CFR 57.22310 - Electrical cables (I-C mines).
Code of Federal Regulations, 2010 CFR
2010-07-01
... Standards for Methane in Metal and Nonmetal Mines Equipment § 57.22310 Electrical cables (I-C mines). Electrical cables used to power submersible sump pumps shall be accepted or approved by MSHA as flame... be sealed to prevent entry of explosive gas or dust. [57 FR 61223, Dec. 23, 1992] ...
Code of Federal Regulations, 2010 CFR
2010-10-01
... TELEVISION SERVICE Cable Rate Regulation § 76.943 Fines. (a) A franchising authority may impose fines or... specifically at the cable operator, provided the franchising authority has such power under state or local laws. (b) If a cable operator willfully fails to comply with the terms of any franchising authority's order...
46 CFR 116.202 - Plans and information required.
Code of Federal Regulations, 2014 CFR
2014-10-01
... electronic format. Information for submitting the VSP electronically can be found at http://www.uscg.mil/HQ... movers; (v) Type and size of generator cables, bus-tie cables, feeders, and branch circuit cables; (vi) Power, lighting, and interior communication panelboards with number of circuits and rating of energy...
46 CFR 116.202 - Plans and information required.
Code of Federal Regulations, 2013 CFR
2013-10-01
... electronic format. Information for submitting the VSP electronically can be found at http://www.uscg.mil/HQ... movers; (v) Type and size of generator cables, bus-tie cables, feeders, and branch circuit cables; (vi) Power, lighting, and interior communication panelboards with number of circuits and rating of energy...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Liu, Shuaishuai; Fifield, Leonard S.; Bowler, Nicola
Cross-linked polyethylene (XLPE) cable insulation material undergoes simultaneous, accelerated thermal and gamma-radiation aging to simulate the long-term aging environment within nuclear power plants (NPPs). A variety of materials characterization tests, including scanning electron microscopy, thermo-gravimetric analysis, differential scanning calorimetry, oxidation induction time, gel-fraction and dielectric properties measurement, are conducted on pristine and differently aged XLPE samples. A preliminary model of one possible aging mechanism of XLPE cable insulation material under gamma radiation at elevated temperature of 115 °C is suggested.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Simmons, Kevin L.; Fifield, Leonard S.; Westman, Matthew P.
The goal of this project is to conceptually demonstrate techniques to repair cables that have degraded through subjection to long-term thermal and radiation exposure in nuclear power plants. In fiscal year 2014 (FY14) we focused on commercially available ethylene-propylene rubber (EPR) as the relevant test material, isolated a high surface area form of the EPR material to facilitate chemical treatment screening and charaterization, and measured chemical changes in the material due to aging and treatment using Fourier Transfrom Infrared (FTIR) spectroscopy.
Power Strategy in DC/DC Converters to Increase Efficiency of Electrical Stimulators.
Aqueveque, Pablo; Acuña, Vicente; Saavedra, Francisco; Debelle, Adrien; Lonys, Laurent; Julémont, Nicolas; Huberland, François; Godfraind, Carmen; Nonclercq, Antoine
2016-06-13
Power efficiency is critical for electrical stimulators. Battery life of wearable stimulators and wireless power transmission in implanted systems are common limiting factors. Boost DC/DC converters are typically needed to increase the supply voltage of the output stage. Traditionally, boost DC/DC converters are used with fast control to regulate the supply voltage of the output. However, since stimulators are acting as current sources, such voltage regulation is not needed. Banking on this, this paper presents a DC/DC conversion strategy aiming to increase power efficiency. It compares, in terms of efficiency, the traditional use of boost converters to two alternatives that could be implemented in future hardware designs.
Rotating Connection for Electrical Cables
NASA Technical Reports Server (NTRS)
Manges, D. R.
1986-01-01
Cable reel provides electrical connections between fixed structure and rotating one. Reel carries power and signal lines while allowing rotating structure to turn up to 360 degrees with respect to fixed structure. Reel replaces sliprings. Can be used to electrically connect arm of robot with body. Reel releases cable to rotating part as it turns and takes up cable as rotating part comes back to its starting position, without tangling, twisting, or kinking.
Design, development, fabrication and testing of high temperature Flat Conductor Cable (FCC)
NASA Technical Reports Server (NTRS)
Rigling, W. S.
1974-01-01
The results are presented of a development program for a flat, 25-conductor signal cable and a flat, 3-conductor power cable. Flat cables employ conductors made of strips or flattened round copper conductors insulated with polyimide films. It is shown that conductor thickness ranges from 0.003 to 0.010 inch, and begins to soften and loose mechanical strength at temperatures above 200 C.
Modified Perfect Harmonics Cancellation Control of a Grid Interfaced SPV Power Generation
NASA Astrophysics Data System (ADS)
Singh, B.; Shahani, D. T.; Verma, A. K.
2015-03-01
This paper deals with a grid interfaced solar photo voltaic (SPV) power generating system with modified perfect harmonic cancellation (MPHC) control for power quality improvement in terms of mitigation of the current harmonics, power factor correction, control of point of common coupling (PCC) voltage with reactive power compensation and load balancing in a three phase distribution system. The proposed grid interfaced SPV system consists of a SPV array, a dc-dc boost converter and a voltage source converter (VSC) used for the compensation of other connected linear and nonlinear loads at PCC. The reference grid currents are estimated using MPHC method and control signals are derived by using pulse width modulation (PWM) current controller of VSC. The SPV power is fed to the common dc bus of VSC and dc-dc boost converter using maximum power point tracking (MPPT). The dc link voltage of VSC is regulated by using dc voltage proportional integral (PI) controller. The analysis of the proposed SPV power generating system is carried out under dc/ac short circuit and severe SPV-SX and SPV-TX intrusion.
NASA Astrophysics Data System (ADS)
Afanasyev, A. P.; Bazhenov, R. I.; Luchaninov, D. V.
2018-05-01
The main purpose of the research is to develop techniques for defining the best technical and economic trajectories of cables in urban power systems. The proposed algorithms of calculation of the routes for laying cables take into consideration topological, technical and economic features of the cabling. The discrete option of an algorithm Fast marching method is applied as a calculating tool. It has certain advantages compared to other approaches. In particular, this algorithm is cost-effective to compute, therefore, it is not iterative. Trajectories of received laying cables are considered as optimal ones from the point of view of technical and economic criteria. They correspond to the present rules of modern urban development.
Type B investigation of electrical fault in 351 Substation, December 4, 1994
DOE Office of Scientific and Technical Information (OSTI.GOV)
Debban, H.L.; Shearer, C.A.; Boger, R.M.
1995-02-01
On December 4, 1994, at 2132:10 hours, an electrical failure of a cable-tapping splice resulted in a fire in the 300 Area of the DOE Hanford Site. The fire occurred in the yard of Substation 351 in electrical Vault R122V, where the cable-tapping splice was located. The fire incinerated all cables passing to and through the vault causing them to fail. The failure of the cables resulted in a power outage to twenty customers in the 300 Area. The vault was electrically isolated, and power was restored to the electrical distribution system at 2311 hours. This report contains the accidentmore » scenario, accident analysis, direct cause and root and contributing causes.« less
Effect of the surface roughness on interfacial breakdown between two dielectric surfaces
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fournier, D.
1996-12-31
Cable splices and accessories are the weak link in an underground power distribution system. Investigations of problems related to cable splices and accessories becomes quite intricate once the simpler causes of failures are dismissed to allow more complex phenomena to be examined. The interfacial breakdown between two internal dielectric surfaces represents one of the major causes of failure for power cable joints. In order to better understand this phenomenon, breakdown experiments were performed at interfaces found in cable splices. An experimental jig was designed to induce breakdown between dielectric surfaces longitudinally along their interface. Effects of surface roughness at EPDM/XLPEmore » and EPDM/EPDM interfaces as well as the presence of silicone grease are taken into account.« less
Emulating DC constant power load: a robust sliding mode control approach
NASA Astrophysics Data System (ADS)
Singh, Suresh; Fulwani, Deepak; Kumar, Vinod
2017-09-01
This article presents emulation of a programmable power electronic, constant power load (CPL) using a dc/dc step-up (boost) converter. The converter is controlled by a robust sliding mode controller (SMC). A novel switching surface is proposed to ensure a required power sunk by the converter. The proposed dc CPL is simple in design, has fast dynamic response and high accuracy, and offers an inexpensive alternative to study converters for cascaded dc distribution power system applications. Furthermore, the proposed CPL is sufficiently robust against the input voltage variations. A laboratory prototype of the proposed dc CPL has been developed and validated with SMC realised through OPAL-RT platform. The capability of the proposed dc CPL is confirmed via experimentations in varied scenarios.
NASA Astrophysics Data System (ADS)
Jou, H. L.; Wu, J. C.; Lin, J. H.; Su, W. N.; Wu, T. S.; Lin, Y. T.
2017-11-01
The operation strategy for a small-capacity grid-tied DC-coupling power converter interface (GDPCI) integrating wind energy, solar energy and battery energy storage is proposed. The GDPCI is composed of a wind generator, a solar module set a battery bank, a boost DC-DC power converter (DDPC), a bidirectional DDPC power converter, an AC-DC power converter (ADPC) and a five-level DC-AC inverter (DAI). A solar module set, a wind generator and a battery bank are coupled to the common DC bus through the boost DDPC, the ADPC and the bidirectional DDPC, respectively. For verifying the performance of the GDPCI under different operation modes, computer simulation is carried out by PSIM.
NASA Technical Reports Server (NTRS)
Jeffries, K. S.; Renz, D. D.
1984-01-01
A parametric analysis was performed of transmission cables for transmitting electrical power at high voltage (up to 1000 V) and high frequency (10 to 30 kHz) for high power (100 kW or more) space missions. Large diameter (5 to 30 mm) hollow conductors were considered in closely spaced coaxial configurations and in parallel lines. Formulas were derived to calculate inductance and resistance for these conductors. Curves of cable conductance, mass, inductance, capacitance, resistance, power loss, and temperature were plotted for various conductor diameters, conductor thickness, and alternating current frequencies. An example 5 mm diameter coaxial cable with 0.5 mm conductor thickness was calculated to transmit 100 kW at 1000 Vac, 50 m with a power loss of 1900 W, an inductance of 1.45 micron and a capacitance of 0.07 micron-F. The computer programs written for this analysis are listed in the appendix.
ERIC Educational Resources Information Center
Ohio State Univ., Columbus. National Center for Research in Vocational Education.
This curriculum outline, instructor's guide, and student's guide for a secondary-postsecondary-level course in construction electrician/power and communications cable splicing are one of a number of military-developed curriculum packages developed for adaptation to vocational instruction and curriculum development in a civilian setting. Purpose…
46 CFR 28.865 - Wiring methods and materials.
Code of Federal Regulations, 2014 CFR
2014-10-01
.... (e) Cable and wire for power and lighting circuits must: (1) For circuits of less than 50 volts, meet... FISHING INDUSTRY VESSELS Aleutian Trade Act Vessels § 28.865 Wiring methods and materials. (a) All cable... the circuit. (b) Each conductor must be No. 22 AWG or larger. Conductors in power and lighting...
46 CFR 28.865 - Wiring methods and materials.
Code of Federal Regulations, 2013 CFR
2013-10-01
.... (e) Cable and wire for power and lighting circuits must: (1) For circuits of less than 50 volts, meet... FISHING INDUSTRY VESSELS Aleutian Trade Act Vessels § 28.865 Wiring methods and materials. (a) All cable... the circuit. (b) Each conductor must be No. 22 AWG or larger. Conductors in power and lighting...
46 CFR 28.865 - Wiring methods and materials.
Code of Federal Regulations, 2012 CFR
2012-10-01
.... (e) Cable and wire for power and lighting circuits must: (1) For circuits of less than 50 volts, meet... FISHING INDUSTRY VESSELS Aleutian Trade Act Vessels § 28.865 Wiring methods and materials. (a) All cable... the circuit. (b) Each conductor must be No. 22 AWG or larger. Conductors in power and lighting...
46 CFR 28.865 - Wiring methods and materials.
Code of Federal Regulations, 2011 CFR
2011-10-01
.... (e) Cable and wire for power and lighting circuits must: (1) For circuits of less than 50 volts, meet... FISHING INDUSTRY VESSELS Aleutian Trade Act Vessels § 28.865 Wiring methods and materials. (a) All cable... the circuit. (b) Each conductor must be No. 22 AWG or larger. Conductors in power and lighting...
Detection of Local Temperature Change on HTS Cables via Time-Frequency Domain Reflectometry
NASA Astrophysics Data System (ADS)
Bang, Su Sik; Lee, Geon Seok; Kwon, Gu-Young; Lee, Yeong Ho; Ji, Gyeong Hwan; Sohn, Songho; Park, Kijun; Shin, Yong-June
2017-07-01
High temperature superconducting (HTS) cables are drawing attention as transmission and distribution cables in future grid, and related researches on HTS cables have been conducted actively. As HTS cables have come to the demonstration stage, failures of cooling systems inducing quench phenomenon of the HTS cables have become significant. Several diagnosis of the HTS cables have been developed but there are still some limitations of the experimental setup. In this paper, a non-destructive diagnostic technique for the detection of the local temperature change point is proposed. Also, a simulation model of HTS cables with a local temperature change point is suggested to verify the proposed diagnosis. The performance of the diagnosis is checked by comparative analysis between the proposed simulation results and experiment results of a real-world HTS cable. It is expected that the suggested simulation model and diagnosis will contribute to the commercialization of HTS cables in the power grid.
DC-DC power converter research for Orbiter/Station power exchange
NASA Technical Reports Server (NTRS)
Ehsani, M.
1993-01-01
This project was to produce innovative DC-DC power converter concepts which are appropriate for the power exchange between the Orbiter and the Space Station Freedom (SSF). The new converters must interface three regulated power buses on SSF, which are at different voltages, with three fuel cell power buses on the Orbiter which can be at different voltages and should be tracked independently. Power exchange is to be bi-directional between the SSF and the Orbiter. The new converters must satisfy the above operational requirements with better weight, volume, efficiency, and reliability than is available from the present conventional technology. Two families of zero current DC-DC converters were developed and successfully adapted to this application. Most of the converters developed are new and are presented.
Direct current uninterruptible power supply method and system
Sinha, Gautam
2003-12-02
A method and system are described for providing a direct current (DC) uninterruptible power supply with the method including, for example: continuously supplying fuel to a turbine; converting mechanical power from the turbine into alternating current (AC) electrical power; converting the AC electrical power to DC power within a predetermined voltage level range; supplying the DC power to a load; and maintaining a DC load voltage within the predetermined voltage level range by adjusting the amount of fuel supplied to the turbine.
Rotary high power transfer apparatus
NASA Technical Reports Server (NTRS)
Jacobson, Peter E. (Inventor); Porter, Ryan S. (Inventor)
1987-01-01
An apparatus for reducing terminal-to-terminal circuit resistance and enhancing heat transfer in a rotary power transfer apparatus of the roll ring type comprising a connecting thimble for attaching an external power cable to a cone shaped terminal which is attached to a tab integral to an outer ring. An inner ring having a spherical recess mates with the spherical end of a tie connector. A cone shaped terminal is fitted to a second connecting thimble for attaching a second external power cable.
Goertz, R.C.; Lindberg, J.F.
1962-01-30
A reeling device is designed for an electrical cable supplying power to the slave slde of a remote control manipulator mounted on a movable vehicle. As the vehicle carries the slave side about in a closed room, the device reels the cable in and out to maintain a variable length of the cable between the vehicle and a cable inlet in the wall of the room. The device also handles a fixed length of cable between the slave side and the vehicle, in spite of angular movement of the slave side with respect to the vehicle. (AEC)
Variable Frequency Operations of an Offshore Wind Power Plant with HVDC-VSC: Preprint
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gevorgian, V.; Singh, M.; Muljadi, E.
2011-12-01
In this paper, a constant Volt/Hz operation applied to the Type 1 wind turbine generator. Various control aspects of Type 1 generators at the plant level and at the turbine level will be investigated. Based on DOE study, wind power generation may reach 330 GW by 2030 at the level of penetration of 20% of the total energy production. From this amount of wind power, 54 GW of wind power will be generated at offshore wind power plants. The deployment of offshore wind power plants requires power transmission from the plant to the load center inland. Since this power transmissionmore » requires submarine cable, there is a need to use High-Voltage Direct Current (HVDC) transmission. Otherwise, if the power is transmitted via alternating current, the reactive power generated by the cable capacitance may cause an excessive over voltage in the middle of the transmission distance which requires unnecessary oversized cable voltage breakdown capability. The use of HVDC is usually required for transmission distance longer than 50 kilometers of submarine cables to be economical. The use of HVDC brings another advantage; it is capable of operating at variable frequency. The inland substation will be operated to 60 Hz synched with the grid, the offshore substation can be operated at variable frequency, thus allowing the wind power plant to be operated at constant Volt/Hz. In this paper, a constant Volt/Hz operation applied to the Type 1 wind turbine generator. Various control aspects of Type 1 generators at the plant level and at the turbine level will be investigated.« less
Frequency Domain Reflectometry NDE for Aging Cables in Nuclear Power Plants
DOE Office of Scientific and Technical Information (OSTI.GOV)
Glass, Samuel W.; Jones, Anthony M.; Fifield, Leonard S.
Cable insulation polymers are among the more susceptible materials to age-related degradation within a nuclear power plant. This is recognized by both regulators and utilities, so all plants have developed cable aging management programs to detect damage before critical component failure in compliance with regulatory guidelines. Although a wide range of tools are available to evaluate cables and cable systems, cable aging management programs vary in how condition monitoring and nondestructive examinations are conducted as utilities search for the most reliable and cost-effective ways to assess cable system condition. Frequency domain reflectometry (FDR) is emerging as one valuable tool tomore » locate and assess damaged portions of a cable system with minimal cost and only requires access in most cases to one of the cable terminal ends. Since laboratory studies to evaluate the use of FDR for inspection of aged cables can be expensive and data interpretation may be confounded by multiple factors which influence results, a model-based approach is desired to parametrically investigate the effect of insulation material damage in a controlled manner. This work describes development of a physics-based FDR model which uses finite element simulations of cable segments in conjunction with cascaded circuit element simulations to efficiently study a cable system. One or more segments of the cable system model have altered physical or electrical properties which represent the degree of damage and the location of the damage in the system. This circuit model is then subjected to a simulated FDR examination. The modeling approach is verified using several experimental cases and by comparing it to a commercial simulator suitable for simulation of some cable configurations. The model is used to examine a broad range of parameters including defect length, defect profile, degree of degradation, number and location of defects, FDR bandwidth, and addition of impedance-matched extensions to minimize the end-shadow effect.« less
Frequency domain reflectometry modeling for nondestructive evaluation of nuclear power plant cables
NASA Astrophysics Data System (ADS)
Glass, S. W.; Fifield, L. S.; Jones, A. M.; Hartman, T. S.
2018-04-01
Cable insulation polymers are among the more susceptible materials to age-related degradation within a nuclear power plant. This is recognized by both regulators and utilities, so all plants have developed cable aging management programs to detect damage before critical component failure in compliance with regulatory guidelines. Although a wide range of tools are available to evaluate cables and cable systems, cable aging management programs vary in how condition monitoring and nondestructive examinations are conducted as utilities search for the most reliable and cost-effective ways to assess cable system condition. Frequency domain reflectometry (FDR) is emerging as one valuable tool to locate and assess damaged portions of a cable system with minimal cost and only requires access in most cases to one of the cable terminal ends. Since laboratory studies to evaluate the use of FDR for inspection of aged cables can be expensive and data interpretation may be confounded by multiple factors which influence results, a model-based approach is desired to parametrically investigate the effect of insulation material damage in a controlled manner. This work describes development of a physics-based FDR model which uses finite element simulations of cable segments in conjunction with cascaded circuit element simulations to efficiently study a cable system. One or more segments of the cable system model have altered physical or electrical properties which represent the degree of damage and the location of the damage in the system. This circuit model is then subjected to a simulated FDR examination. The modeling approach is verified using several experimental cases and by comparing it to a commercial simulator suitable for simulation of some cable configurations. The model is used to examine a broad range of parameters including defect length, defect profile, degree of degradation, number and location of defects, FDR bandwidth, and addition of impedance-matched extensions to minimize the end-shadow effect.
New method for the detection and monitoring of subsea power cable
NASA Astrophysics Data System (ADS)
Held, Philipp; Schneider, Jens; Feldens, Peter; Wilken, Dennis
2016-04-01
Marine renewable energy farms, no matter what kind of, have in common that they need a connection with the onshore power grid. Thus, not only their offshore generation facilities could have impacts on the surrounding environment, but also associated submarine power cables. These cables have to be buried in the seabed - at least in coastal heavy shipping environments - for safety reasons. Cable laying disturbs the local seafloor and the sub-bottom. Refillment of dredged sediments are expected softer than the original material and could be washed away by currents. Therefore, buried cables have to be repeatedly monitored to ensure their burial depth. This study presents a new method for efficient cable detection. A parametric echosounder system using 15 kHz as secondary frequency was adapted to investigate the angular response of sub-bottom backscatter strength of layered mud and to introduce a new method for enhanced acoustic detection of buried targets. Adaptations to achieve both vertical (0°) and non-vertical inclination of incident sound on the seabed (1-15°, 30°, 45°, and 60°) comprise mechanical tilting of the acoustic transducer and electronic beam steering. A sample data set was acquired at a study site at 18 m water depth and a flat and muddy seafloor. At this site, a 0.1 m diameter power cable is buried 1-2 m below the sea floor. Surveying the cable with vertical incidence revealed that the buried cable can hardly be discriminated against the backscatter strength of the layered mud. However, the backscatter strength of layered mud was found to strongly decrease at >3±0.5° incidence and the layered mud echo pattern vanished beyond 5°. As a consequence the visual recognition of the cable echo in acoustic images improves for higher incidence angles of 15°, 30°, 45°, and 60°. Data analysis support this visual impression. The size of the cable echo pattern was found to linearly increase with incidence, whereas the signal-to-noise ratio peaks at about 40°. At the peak, the signal-to-noise ratio is up to 2.6 times higher than at normal incidence. The effects are attributed to reflection loss from layered mud at larger incidence and to the scattering of the 0.1 m diameter buried cable. Thus, the presented method is suitable for cable detection and monitoring and can also provide information of the surrounding sedimentological strati. One of its advantages is that it is based on small and mobile transducers and is therefore useable on reasonable small survey platforms. We foresee a large potential using the presented mechanic or electronic sound inclination approach for enhanced sub-bottom classification and to better detect shallow buried acoustic scatterers like cables, pipelines, stones, dumping material (mines, waste), submerged shipwrecks, archaeological settlement remains, manganese nodules and shallow gas.
Determination of appropriate DC voltage for switched mode power supply (SMPS) loads
NASA Astrophysics Data System (ADS)
Setiawan, Eko Adhi; Setiawan, Aiman; Purnomo, Andri; Djamal, Muchlishah Hadi
2017-03-01
Nowadays, most of modern and efficient household electronic devices operated based on Switched Mode Power Supply (SMPS) technology which convert AC voltage from the grid to DC voltage. Based on theory and experiment, SMPS loads could be supplied by DC voltage. However, the DC voltage rating to energize electronic home appliances is not standardized yet. This paper proposed certain method to determine appropriate DC voltage, and investigated comparison of SMPS power consumption which is supplied from AC and DC voltage. To determine the appropriate DC voltage, lux value of several lamps which have same specification energized by using AC voltage and the results is using as reference. Then, the lamps were supplied by various DC voltage to obtain the trends of the lux value to the applied DC voltage. After that, by using the trends and the reference lux value, the appropriate DC voltage can be determined. Furthermore, the power consumption on home appliances such as mobile phone, laptop and personal computer by using AC voltage and the appropriate DC voltage were conducted. The results show that the total power consumption of AC system is higher than DC system. The total power (apparent power) consumed by the lamp, mobile phone and personal computer which operated in 220 VAC were 6.93 VA, 34.31 VA and 105.85 VA respectively. On the other hand, under 277 VDC the load consumption were 5.83 W, 19.11 W and 74.46 W respectively.
AC/DC Smart Control And Power Sharing of DC Distribution Systems
2012-02-10
system losses will decrease since the semiconductor losses due to switching in converter are reduced. The use of DC power systems to supply...cells yield variable DC voltage. In stand-alone systems , in order to be able to make full use of the generated power and to feed the loads, a controlled...alternate sources connected to the DC Distribution System
30 CFR 77.805 - Cable couplers and connection boxes; minimum design requirements.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Cable couplers and connection boxes; minimum... connection boxes; minimum design requirements. (a)(1) Couplers that are used in medium- or high-voltage power... materials other than metal. (2) Cable couplers shall be adequate for the intended current and voltage. (3...
30 CFR 77.805 - Cable couplers and connection boxes; minimum design requirements.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Cable couplers and connection boxes; minimum... connection boxes; minimum design requirements. (a)(1) Couplers that are used in medium- or high-voltage power... materials other than metal. (2) Cable couplers shall be adequate for the intended current and voltage. (3...
46 CFR 111.60-4 - Minimum cable conductor size.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 46 Shipping 4 2012-10-01 2012-10-01 false Minimum cable conductor size. 111.60-4 Section 111.60-4 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS... conductor must be #18 AWG (0.82 mm2) or larger except— (a) Each power and lighting cable conductor must be...
46 CFR 111.60-4 - Minimum cable conductor size.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 46 Shipping 4 2013-10-01 2013-10-01 false Minimum cable conductor size. 111.60-4 Section 111.60-4 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS... conductor must be #18 AWG (0.82 mm2) or larger except— (a) Each power and lighting cable conductor must be...
46 CFR 111.60-4 - Minimum cable conductor size.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 46 Shipping 4 2014-10-01 2014-10-01 false Minimum cable conductor size. 111.60-4 Section 111.60-4 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS... conductor must be #18 AWG (0.82 mm2) or larger except— (a) Each power and lighting cable conductor must be...
30 CFR 77.805 - Cable couplers and connection boxes; minimum design requirements.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Cable couplers and connection boxes; minimum... WORK AREAS OF UNDERGROUND COAL MINES Surface High-Voltage Distribution § 77.805 Cable couplers and connection boxes; minimum design requirements. (a)(1) Couplers that are used in medium- or high-voltage power...
30 CFR 77.805 - Cable couplers and connection boxes; minimum design requirements.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Cable couplers and connection boxes; minimum... WORK AREAS OF UNDERGROUND COAL MINES Surface High-Voltage Distribution § 77.805 Cable couplers and connection boxes; minimum design requirements. (a)(1) Couplers that are used in medium- or high-voltage power...
30 CFR 77.805 - Cable couplers and connection boxes; minimum design requirements.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Cable couplers and connection boxes; minimum... WORK AREAS OF UNDERGROUND COAL MINES Surface High-Voltage Distribution § 77.805 Cable couplers and connection boxes; minimum design requirements. (a)(1) Couplers that are used in medium- or high-voltage power...
Simultaneous Thermal and Gamma Radiation Aging of Electrical Cable Polymers
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fifield, Leonard S.
The polymers used for insulation in nuclear power plant electrical cables are susceptible to aging during long term operation. Elevated temperature is the primary contributor to changes in polymer structure that result loss of mechanical and electrical properties, but gamma radiation is also a significant source of degradation for polymers used within relevant plant locations. Despite many years of polymer degradation research, the combined effects of simultaneous exposure to thermal and radiation stress are not well understood. As nuclear operators contemplate and prepare for extended operations beyond initial license periods, a predictive understanding of exposure-based cable material degradation is becomingmore » an increasingly important input to safety, licensing, operations and economic decisions. We are focusing on carefully-controlled simultaneous thermal and gamma radiation accelerating aging and characterization of the most common nuclear cable polymers to understand the relative contributions of temperature, time, dose and dose rate to changes in cable polymer material structure and properties. Improved understanding of cable performance in long term operation will help support continued sustainable nuclear power generation.« less
Bunch, K J; Swanson, J; Vincent, T J; Murphy, M F G
2015-09-01
Epidemiological evidence of increased risks for childhood leukaemia from magnetic fields has implicated, as one source of such fields, high-voltage overhead lines. Magnetic fields are not the only factor that varies in their vicinity, complicating interpretation of any associations. Underground cables (UGCs), however, produce magnetic fields but have no other discernible effects in their vicinity. We report here the largest ever epidemiological study of high voltage UGCs, based on 52,525 cases occurring from 1962-2008, with matched birth controls. We calculated the distance of the mother's address at child's birth to the closest 275 or 400 kV ac or high-voltage dc UGC in England and Wales and the resulting magnetic fields. Few people are exposed to magnetic fields from UGCs limiting the statistical power. We found no indications of an association of risk with distance or of trend in risk with increasing magnetic field for leukaemia, and no convincing pattern of risks for any other cancer. Trend estimates for leukaemia as shown by the odds ratio (and 95% confidence interval) per unit increase in exposure were: reciprocal of distance 0.99 (0.95-1.03), magnetic field 1.01 (0.76-1.33). The absence of risk detected in relation to UGCs tends to add to the argument that any risks from overhead lines may not be caused by magnetic fields.
The manufacture of flat conductor cable
NASA Technical Reports Server (NTRS)
Angele, W.
1974-01-01
The major techniques are described for fabricating flat conductor cable (FCC). Various types of FCC, including unshielded, shielded, power, and signal, in both existing and conceptual constructions, are covered.
Two new families of high-gain dc-dc power electronic converters for dc-microgrids
NASA Astrophysics Data System (ADS)
Prabhala, Venkata Anand Kishore
Distributing the electric power in dc form is an appealing solution in many applications such as telecommunications, data centers, commercial buildings, and microgrids. A high gain dc-dc power electronic converter can be used to individually link low-voltage elements such as solar panels, fuel cells, and batteries to the dc voltage bus which is usually 400 volts. This way, it is not required to put such elements in a series string to build up their voltages. Consequently, each element can function at it optimal operating point regardless of the other elements in the system. In this dissertation, first a comparative study of dc microgrid architectures and their advantages over their ac counterparts is presented. Voltage level selection of dc distribution systems is discussed from the cost, reliability, efficiency, and safety standpoints. Next, a new family of non-isolated high-voltage-gain dc-dc power electronic converters with unidirectional power flow is introduced. This family of converters benefits from a low voltage stress across its switches. The proposed topologies are versatile as they can be utilized as single-input or double-input power converters. In either case, they draw continuous currents from their sources. Lastly, a bidirectional high-voltage-gain dc-dc power electronic converter is proposed. This converter is comprised of a bidirectional boost converter which feeds a switched-capacitor architecture. The switched-capacitor stage suggested here has several advantages over the existing approaches. For example, it benefits from a higher voltage gain while it uses less number of capacitors. The proposed converters are highly efficient and modular. The operating modes, dc voltage gain, and design procedure for each converter are discussed in details. Hardware prototypes have been developed in the lab. The results obtained from the hardware agree with those of the simulation models.
Predictive aging results for cable materials in nuclear power plants
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gillen, K.T.; Clough, R.L.
1990-11-01
In this report, we provide a detailed discussion of methodology of predicting cable degradation versus dose rate, temperature, and exposure time and its application to data obtained on a number of additional nuclear power plant cable insulation (a hypalon, a silicon rubber and two ethylenetetrafluoroethylenes) and jacket (a hypalon) materials. We then show that the predicted, low-dose-rate results for our materials are in excellent agreement with long-term (7 to 9 years), low dose-rate results recently obtained for the same material types actually aged under nuclear power plant conditions. Based on a combination of the modelling and long-term results, we findmore » indications of reasonably similar degradation responses among several different commercial formulations for each of the following generic'' materials: hypalon, ethylenetetrafluoroethylene, silicone rubber and PVC. If such generic'' behavior can be further substantiated through modelling and long-term results on additional formulations, predictions of cable life for other commercial materials of the same generic types would be greatly facilitated. Finally, to aid utilities in their cable life extension decisions, we utilize our modelling results to generate lifetime prediction curves for the materials modelled to data. These curves plot expected material lifetime versus dose rate and temperature down to the levels of interest to nuclear power plant aging. 18 refs., 30 figs., 3 tabs.« less
Integrated arc suppression unit for defect reduction in PVD applications
NASA Astrophysics Data System (ADS)
Li, Jason; Narasimhan, Murali K.; Pavate, Vikram; Loo, David; Rosenblum, Steve; Trubell, Larry; Scholl, Richard; Seamons, Scott; Hagerty, Chris; Ramaswami, Sesh
1997-09-01
Arcing between the target and plasma during PVD deposition causes substantial damage to the target and splats and other contamination on the deposited films. Arc-related damages and defects are frequently encountered in microelectronics manufacturing and contributes largely to reduced wafer yields. Arcing is caused largely by the charge buildup at the contaminated sites on the target surface that contains either nonconducting inclusions or nodules. Arc suppression is a key issue for defect reduction, yield improvement and for reliable high quality metallization. An Integrated Arc Suppression Unit (IASU) has been designed for Endura HP PVDTM sputtering sources. The integrated design reduces cable length from unit to source and reduces electrical energy stored in the cable. Active arc handling mode, proactive arc prevention mode, and passive by-pass arc counting mode are incorporated into the same unit. The active mode is designed to quickly respond to chamber conditions, like a large chamber voltage drop, that signals a arc. The self run mode is designed to proactively prevent arc formation by pulsing and reversing target voltage at 50 kHz. The design of the IASU, also called mini small package arc repression circuit--low energy unit (mini Sparc-le), has been optimized for various DC magnetron sources, plasma stability, chamber impedance, power matching, CE MARK test, and power dissipation. Process characterization with Ti, TiN and Al sputtering indicates that the unit has little adverse impact on film properties. Mini Sparc-le unit has been shown here to significantly reduce splats occurrence in Al sputtering. Marathon test of the unit with Ti/TiN test demonstrated the unit's reliability and its ability to reduce sensitivity of defects to target characteristics.
Hirose, H
1997-01-01
This paper proposes a new treatment for electrical insulation degradation. Some types of insulation which have been used under various circumstances are considered to degrade at various rates in accordance with their stress circumstances. The cross-linked polyethylene (XLPE) insulated cables inspected by major Japanese electric companies clearly indicate such phenomena. By assuming that the inspected specimen is sampled from one of the clustered groups, a mixed degradation model can be constructed. Since the degradation of the insulation under common circumstances is considered to follow a Weibull distribution, a mixture model and a Weibull power law can be combined. This is called The mixture Weibull power law model. By using the maximum likelihood estimation for the newly proposed model to Japanese 22 and 33 kV insulation class cables, they are clustered into a certain number of groups by using the AIC and the generalized likelihood ratio test method. The reliability of the cables at specified years are assessed.
The dc power circuits: A compilation
NASA Technical Reports Server (NTRS)
1972-01-01
A compilation of reports concerning power circuits is presented for the dissemination of aerospace information to the general public as part of the NASA Technology Utilization Program. The descriptions for the electronic circuits are grouped as follows: dc power supplies, power converters, current-voltage power supply regulators, overload protection circuits, and dc constant current power supplies.
Multi-port power router and its impact on resilient power grid systems
NASA Astrophysics Data System (ADS)
Kado, Yuichi; Iwatsuki, Katsumi; Wada, Keiji
2016-02-01
We propose a Y-configuration power router as a unit cell to easily construct a power delivery system that can meet many types of user requirements. The Y-configuration power router controls the direction and magnitude of power flow among three ports regardless of DC and AC. We constructed a prototype three-way isolated DC/DC converter that is the core unit of the Y-configuration power router and tested the power flow control operation. Experimental results revealed that our methodology based on the governing equation was appropriate for the power flow control of the three-way DC/DC converter. In addition, the hexagonal distribution network composed of the power routers has the ability to easily interchange electric power between autonomous microgrid cells. We also explored the requirements for communication between energy routers to achieve dynamic adjustments of energy flow in a coordinated manner and its impact on resilient power grid systems.
Mobile Centers For Secondary Power Distribution
NASA Technical Reports Server (NTRS)
Mears, Robert L.
1990-01-01
Concept for distribution of 60-Hz ac power in large building devoted to assembly and testing of equipment improves safety, reduces number of outlets and lengthy cables, and readily accommodates frequent changes in operations and configuration. Power from floor recess fed via unobtrusive cable to portable power management center. A cart containing variety of outlets and circuit breakers, wheeled to convenient location near equipment to be assembled or tested. Power distribution system presents larger range of operational configurations than fixed location. Meets tighter standards to feed computers and delicate instruments. Industrial-grade power suitable for power tools and other hardware. Three-phase and single-phase outlets available from each.
Non-Rocket Missile Rope Launcher
NASA Technical Reports Server (NTRS)
Bolonkin, Alexander
2002-01-01
The method, installation, and estimation for delivering payload and missiles into outer space are presented. This method uses, in general, the engines and straight or closed-loop cables disposed on a planet surface. The installation consists of a space apparatus, power drive stations located along trajectory of the apparatus, the cables connected to the apparatus and to the power stations, a system for suspending the cable, and disconnected device. The drive stations accelerate the apparatus up to hypersonic speed. The estimations and computations show the possibility of making these projects a reality in a short period of time (see attached project: launcher for missiles and loads). The launch will be very cheap $1-$2 per LB. We need only light strong cable, which can be made from artificial fibers, whiskers, nanotubes, which exist in industry and scientific laboratories.
Dc-To-Dc Converter Uses Reverse Conduction Of MOSFET's
NASA Technical Reports Server (NTRS)
Gruber, Robert P.; Gott, Robert W.
1991-01-01
In modified high-power, phase-controlled, full-bridge, pulse-width-modulated dc-to-dc converters, switching devices power metal oxide/semiconductor field-effect transistors (MOSFET's). Decreases dissipation of power during switching by eliminating approximately 0.7-V forward voltage drop in anti-parallel diodes. Energy-conversion efficiency increased.
Static and dynamic parasitic magnetizations and their control in superconducting accelerator dipoles
NASA Astrophysics Data System (ADS)
Collings, E. W.; Sumption, M. D.
2001-05-01
Long dipole magnets guide the particle beams in synchrotron-type high energy accelerators. In principal Cu-wound DC-excited dipoles could be designed to deliver a very uniform transverse bore field, i.e. with small or negligible harmonic (multipolar) distortion. But if the Cu is replaced by (a) superconducting strand that is (b) wound into a Rutherford cable carrying a time-varying transport current, extra magnetizations present within the windings cause distortions of the otherwise uniform field. The static (persistent-current) strand magnetization can be reduced by reducing the filament diameter, and the residue compensated or corrected by strategically placed active or passive components. The cable’s interstrand coupling currents can be controlled by increasing the interstrand contact resistance by: adjusting the level of native oxidation of the strand, coating it, or by inserting a ribbon-like core into the cable itself. Methods of locally compensating the magnetization of NbTi and Nb 3Sn strand and cable are discussed, progress in coupling-current suppression through the use of coatings and cores is reviewed, and a method of simultaneously reducing both the static and dynamic magnetizations of a NbTi cable by means of a thin Ni core is suggested.
Material Selection for Cable Gland to Improved Reliability of the High-hazard Industries
NASA Astrophysics Data System (ADS)
Vashchuk, S. P.; Slobodyan, S. M.; Deeva, V. S.; Vashchuk, D. S.
2018-01-01
The sealed cable glands (SCG) are available to ensure safest connection sheathed single wire for the hazard production facility (nuclear power plant and others) the same as pilot cable, control cables, radio-frequency cables et al. In this paper, we investigate the specifics of the material selection of SCG with the express aim of hazardous man-made facility. We discuss the safe working conditions for cable glands. The research indicates the sintering powdered metals cables provide the reliability growth due to their properties. A number of studies have demonstrated the verification of material selection. On the face of it, we make findings indicating that double glazed sealed units could enhance reliability. We had evaluated sample reliability under fire conditions, seismic load, and pressure containment failure. We used the samples mineral insulated thermocouple cable.
ERIC Educational Resources Information Center
Public Service Satellite Consortium, Washington, DC.
This collection of papers delivered at the conference provides information on the current state of communications satellite applications and technology, the relationship of cable television and satellites, the role of satellites in public broadcasting, and the future of satellites in serving the needs of the public. Remarks and addresses by the…
Federal Register 2010, 2011, 2012, 2013, 2014
2011-06-13
... Michigan and creates an electric field in the water by pulsing low voltage DC current through steel cables... the U.S. Army Corps of Engineers' simultaneous operation of electric barriers IIA and IIB. Under 5 U.S... selected an electric barrier because it is a non-lethal deterrent with a proven history, which does not...
Determining Remaining Useful Life of Aging Cables in Nuclear Power Plants – Interim Study FY13
DOE Office of Scientific and Technical Information (OSTI.GOV)
Simmons, Kevin L.; Fifield, Leonard S.; Westman, Matthew P.
2013-09-27
The most important criterion for cable performance is its ability to withstand a design-basis accident. With nearly 1000 km of power, control, instrumentation, and other cables typically found in an NPP, it would be a significant undertaking to inspect all of the cables. Degradation of the cable jacket, electrical insulation, and other cable components is a key issue that is likely to affect the ability of the currently installed cables to operate safely and reliably for another 20 to 40 years beyond the initial operating life. The development of one or more nondestructive evaluation (NDE) techniques and supporting models thatmore » could assist in determining the remaining life expectancy of cables or their current degradation state would be of significant interest. The ability to nondestructively determine material and electrical properties of cable jackets and insulation without disturbing the cables or connections has been deemed essential. Currently, the only technique accepted by industry to measure cable elasticity (the gold standard for determining cable insulation degradation) is the indentation measurement. All other NDE techniques are used to find flaws in the cable and do not provide information to determine the current health or life expectancy. There is no single NDE technique that can satisfy all of the requirements needed for making a life-expectancy determination, but a wide range of methods have been evaluated for use in NPPs as part of a continuous evaluation program. The commonly used methods are indentation and visual inspection, but these are only suitable for easily accessible cables. Several NDE methodologies using electrical techniques are in use today for flaw detection but there are none that can predict the life of a cable. There are, however, several physical and chemical ptoperty changes in cable insulation as a result of thermal and radiation damage. In principle, these properties may be targets for advanced NDE methods to provide early warning of aging and degradation. Examples of such key indicators include changes in chemical structure, mechanical modulus, and dielectric permittivity. While some of these indicators are the basis of currently used technologies, there is a need to increase the volume of cable that may be inspected with a single measurement, and if possible, to develop techniques for in-situ inspection (i.e., while the cable is in operation). This is the focus of the present report.« less
47 CFR 11.55 - EAS operation during a State or Local Area emergency.
Code of Federal Regulations, 2010 CFR
2010-10-01
... leaks or liquid spills, widespread power failures, industrial explosions, and civil disorders. (1) DBS...); analog cable systems, digital cable systems, and wireless cable systems must comply with § 11.54(b)(6... programming should comply with § 11.54(b)(8). (5) Upon completion of the State or Local Area EAS transmission...
Development of a Modular, Provider Customized Airway Trainer
2015-11-25
Instructions for Airway Model with sensors and computer ( Raspberry PI ) ........................................ 31 Appendix B: Instructions for...Appendix A: Instructions for Airway Model with sensors and computer ( Raspberry PI ) RASPBERRY PI INSTRUCTIONS 1. Connect multicolor sensor...cable and two blue sensor cables (blue sensor cable orientation does not matter) 2. Plug in power to the screen and raspberry pi ( two separate
Onboard power line conditioning system for an electric or hybrid vehicle
Kajouke, Lateef A.; Perisic, Milun
2016-06-14
A power line quality conditioning system for a vehicle includes an onboard rechargeable direct current (DC) energy storage system and an onboard electrical system coupled to the energy storage system. The energy storage system provides DC energy to drive an electric traction motor of the vehicle. The electrical system operates in a charging mode such that alternating current (AC) energy from a power grid external to the vehicle is converted to DC energy to charge the DC energy storage system. The electrical system also operates in a vehicle-to-grid power conditioning mode such that DC energy from the DC energy storage system is converted to AC energy to condition an AC voltage of the power grid.
Head-mounted LED for optogenetic experiments of freely-behaving animal
NASA Astrophysics Data System (ADS)
Kwon, Ki Yong; Gnade, Andrew G.; Rush, Alexander D.; Patten, Craig D.
2016-03-01
Recent developments in optogenetics have demonstrated the ability to target specific types of neurons with sub-millisecond temporal precision via direct optical stimulation of genetically modified neurons in the brain. In most applications, the beam of a laser is coupled to an optical fiber, which guides and delivers the optical power to the region of interest. Light emitting diodes (LEDs) are an alternative light source for optogenetics and they provide many advantages over a laser based system including cost, size, illumination stability, and fast modulation. Their compact size and low power consumption make LEDs suitable light sources for a wireless optogenetic stimulation system. However, the coupling efficiency of an LED's output light into an optical fiber is lower than a laser due to its noncollimated output light. In typical chronic optogenetic experiment, the output of the light source is transmitted to the brain through a patch cable and a fiber stub implant, and this configuration requires two fiber-to-fiber couplings. Attenuation within the patch cable is potential source of optical power loss. In this study, we report and characterize a recently developed light delivery method for freely-behaving animal experiments. We have developed a head-mounted light source that maximizes the coupling efficiency of an LED light source by eliminating the need for a fiber optic cable. This miniaturized LED is designed to couple directly to the fiber stub implant. Depending on the desired optical power output, the head-mounted LED can be controlled by either a tethered (high power) or battery-powered wireless (moderate power) controller. In the tethered system, the LED is controlled through 40 gauge micro coaxial cable which is thinner, more flexible, and more durable than a fiber optic cable. The battery-powered wireless system uses either infrared or radio frequency transmission to achieve real-time control. Optical, electrical, mechanical, and thermal characteristics of the head-mounted LED were evaluated.
Thermal and vibration testing of ruggedized IR-transmitting fiber cables
NASA Astrophysics Data System (ADS)
Busse, Lynda; Kung, Fred; Florea, Catalin; Shaw, Brandon; Aggarwal, Ishwar; Sanghera, Jas
2013-05-01
We present successful results obtained for thermal/ vibration testing of ruggedized, IR-transmitting chalcogenide glass fiber cables using a government facility with state-of-the-art equipment capable of MIL-SPEC environmental testing. We will also present results of a direct imprinting process to create novel "moth eye" patterned surfaces on the IR fiber cable ends that significantly reduces endface reflection losses from 17% to less than 3%. The cables with these imprinted "moth eye" ends transmit much higher IR laser power without damage than was obtained for previous cables with traditional AR coatings.
DOE Office of Scientific and Technical Information (OSTI.GOV)
A. Ilic; E. Baker; R. Hatcher
The National Spherical Torus Experiment (NSTX) has been designed and installed in the existing facilities at Princeton Plasma Physic Laboratory (PPPL). Most of the hardware, plant facilities, auxiliary sub-systems, and power systems originally used for the Tokamak Fusion Test Reactor (TFTR) have been used with suitable modifications to reflect NSTX needs. The design of the NSTX electrical power system was tailored to suit the available infrastructure and electrical equipment on site. Components were analyzed to verify their suitability for use in NSTX. The total number of circuits and the location of the NSTX device drove the major changes in themore » Power system hardware. The NSTX has eleven (11) circuits to be fed as compared to the basic three power loops for TFTR. This required changes in cabling to insure that each cable tray system has the positive and negative leg of cables in the same tray. Also additional power cabling had to be installed to the new location. The hardware had to b e modified to address the need for eleven power loops. Power converters had to be reconnected and controlled in anti-parallel mode for the Ohmic heating and two of the Poloidal Field circuits. The circuit for the Coaxial Helicity Injection (CHI) System had to be carefully developed to meet this special application. Additional Protection devices were designed and installed for the magnet coils and the CHI. The thrust was to making the changes in the most cost-effective manner without compromising technical requirements. This paper describes the changes and addition to the Electrical Power System components for the NSTX magnet systems.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Simmons, K.L.; Ramuhali, P.; Brenchley, D.L.
2012-09-01
Executive Summary [partial] The purpose of the non-destructive evaluation (NDE) R&D Roadmap for Cables is to support the Materials Aging and Degradation (MAaD) R&D pathway. A workshop was held to gather subject matter experts to develop the NDE R&D Roadmap for Cables. The focus of the workshop was to identify the technical gaps in detecting aging cables and predicting their remaining life expectancy. The workshop was held in Knoxville, Tennessee, on July 30, 2012, at Analysis and Measurement Services Corporation (AMS) headquarters. The workshop was attended by 30 experts in materials, electrical engineering, and NDE instrumentation development from the U.S.more » Nuclear Regulatory Commission (NRC), U.S. Department of Energy (DOE) National Laboratories (Oak Ridge National Laboratory, Pacific Northwest National Laboratory, Argonne National Laboratory, and Idaho National Engineering Laboratory), universities, commercial NDE service vendors and cable manufacturers, and the Electric Power Research Institute (EPRI).« less
The impact of frequency on the performance of microwave ablation.
Sawicki, James F; Shea, Jacob D; Behdad, Nader; Hagness, Susan C
2017-02-01
The use of higher frequencies in percutaneous microwave ablation (MWA) may offer compelling interstitial antenna design advantages over the 915 MHz and 2.45 GHz frequencies typically employed in current systems. To evaluate the impact of higher frequencies on ablation performance, we conducted a comprehensive computational and experimental study of microwave absorption and tissue heating as a function of frequency. We performed electromagnetic and thermal simulations of MWA in ex vivo and in vivo porcine muscle at discrete frequencies in the 1.9-26 GHz range. Ex vivo ablation experiments were performed in the 1.9-18 GHz range. We tracked the size of the ablation zone across frequency for constant input power and ablation duration. Further, we conducted simulations to investigate antenna feed line heating as a function of frequency, input power, and cable diameter. As the frequency was increased from 1.9 to 26 GHz the resulting ablation zone dimensions decreased in the longitudinal direction while remaining relatively constant in the radial direction; thus at higher frequencies the overall ablation zone was more spherical. However, cable heating at higher frequencies became more problematic for smaller diameter cables at constant input power. Comparably sized ablation zones are achievable well above 1.9 GHz, despite increasingly localised power absorption. Specific absorption rate alone does not accurately predict ablation performance, particularly at higher frequencies where thermal diffusion plays an important role. Cable heating due to ohmic losses at higher frequencies may be controlled through judicious choices of input power and cable diameter.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Subudhi, M.
1996-04-01
This report summarizes the findings from a review of published documents dealing with research on the environmental qualification of safety-related electric cables used in nuclear power plants. Simulations of accelerated aging and accident conditions are important considerations in qualifying the cables. Significant research in these two areas has been performed in the US and abroad. The results from studies in France, Germany, and Japan are described in this report. In recent years, the development of methods to monitor the condition of cables has received special attention. Tests involving chemical and physical examination of cable`s insulation and jacket materials, and electricalmore » measurements of the insulation properties of cables are discussed. Although there have been significant advances in many areas, there is no single method which can provide the necessary information about the condition of a cable currently in service. However, it is possible that further research may identify a combination of several methods that can adequately characterize the cable`s condition.« less
NASA Astrophysics Data System (ADS)
Zhou, Ning; Yang, Jia; Cheng, Zheng; Chen, Bo; Su, Yong Chun; Shu, Zhan; Zou, Jin
2017-06-01
Solar photovoltaic power generation is the power generation using solar cell module converting sunlight into DC electric energy. In the paper an equivalent model of solar photovoltaic power generation system is built in RTDS. The main circuit structure of the two-stage PV grid-connected system consists of the DC-DC, DC-AC circuit. The MPPT (Maximum Power Point Tracking) control of the PV array is controlled by adjusting the duty ratio of the DC-DC circuit. The proposed control strategy of constant voltage/constant reactive power (V/Q) control is successfully implemented grid-connected control of the inverter when grid-connected operation. The closed-loop experiment of islanding protection device of photovoltaic power plant on RTDS, verifies the correctness of the simulation model, and the experimental verification can be applied to this type of device.
Design of an Input-Parallel Output-Parallel LLC Resonant DC-DC Converter System for DC Microgrids
NASA Astrophysics Data System (ADS)
Juan, Y. L.; Chen, T. R.; Chang, H. M.; Wei, S. E.
2017-11-01
Compared with the centralized power system, the distributed modularized power system is composed of several power modules with lower power capacity to provide a totally enough power capacity for the load demand. Therefore, the current stress of the power components in each module can then be reduced, and the flexibility of system setup is also enhanced. However, the parallel-connected power modules in the conventional system are usually controlled to equally share the power flow which would result in lower efficiency in low loading condition. In this study, a modular power conversion system for DC micro grid is developed with 48 V dc low voltage input and 380 V dc high voltage output. However, in the developed system control strategy, the numbers of power modules enabled to share the power flow is decided according to the output power at lower load demand. Finally, three 350 W power modules are constructed and parallel-connected to setup a modular power conversion system. From the experimental results, compared with the conventional system, the efficiency of the developed power system in the light loading condition is greatly improved. The modularized design of the power system can also decrease the power loss ratio to the system capacity.
Early Oscillation Detection Technique for Hybrid DC/DC Converters
NASA Technical Reports Server (NTRS)
Wang, Bright L.
2011-01-01
Oscillation or instability is a situation that must be avoided for reliable hybrid DC/DC converters. A real-time electronics measurement technique was developed to detect catastrophic oscillations at early stages for hybrid DC/DC converters. It is capable of identifying low-level oscillation and determining the degree of the oscillation at a unique frequency for every individual model of the converters without disturbing their normal operations. This technique is specially developed for space-used hybrid DC/DC converters, but it is also suitable for most of commercial and military switching-mode power supplies. This is a weak-electronic-signal detection technique to detect hybrid DC/DC converter oscillation presented as a specific noise signal at power input pins. It is based on principles of feedback control loop oscillation and RF signal modulations, and is realized by using signal power spectral analysis. On the power spectrum, a channel power amplitude at characteristic frequency (CPcf) and a channel power amplitude at switching frequency (CPsw) are chosen as oscillation level indicators. If the converter is stable, the CPcf is a very small pulse and the CPsw is a larger, clear, single pulse. At early stage of oscillation, the CPcf increases to a certain level and the CPsw shows a small pair of sideband pulses around it. If the converter oscillates, the CPcf reaches to a higher level and the CPsw shows more high-level sideband pulses. A comprehensive stability index (CSI) is adopted as a quantitative measure to accurately assign a degree of stability to a specific DC/DC converter. The CSI is a ratio of normal and abnormal power spectral density, and can be calculated using specified and measured CPcf and CPsw data. The novel and unique feature of this technique is the use of power channel amplitudes at characteristic frequency and switching frequency to evaluate stability and identify oscillations at an early stage without interfering with a DC/DC converter s normal operation. This technique eliminates the probing problem of a gain/phase margin method by connecting the power input to a spectral analyzer. Therefore, it is able to evaluate stability for all kinds of hybrid DC/DC converters with or without remote sense pins, and is suitable for real-time and in-circuit testing. This frequency-domain technique is more sensitive to detect oscillation at early stage than the time-domain method using an oscilloscope.
75 FR 5690 - Airworthiness Directives; PIAGGIO AERO INDUSTRIES S.p.A. Model P-180 Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2010-02-04
... operator reported a short circuit between a generator power cable and an anti-ice shutoff valve, which was... the damage. If left uncorrected, this situation could lead to short circuits with possible fire and/or... products. The MCAI states: An operator reported a short circuit between a generator power cable and an anti...
Life cycle assessment of overhead and underground primary power distribution.
Bumby, Sarah; Druzhinina, Ekaterina; Feraldi, Rebe; Werthmann, Danae; Geyer, Roland; Sahl, Jack
2010-07-15
Electrical power can be distributed in overhead or underground systems, both of which generate a variety of environmental impacts at all stages of their life cycles. While there is considerable literature discussing the trade-offs between both systems in terms of aesthetics, safety, cost, and reliability, environmental assessments are relatively rare and limited to power cable production and end-of-life management. This paper assesses environmental impacts from overhead and underground medium voltage power distribution systems as they are currently built and managed by Southern California Edison (SCE). It uses process-based life cycle assessment (LCA) according to ISO 14044 (2006) and SCE-specific primary data to the extent possible. Potential environmental impacts have been calculated using a wide range of midpoint indicators, and robustness of the results has been investigated through sensitivity analysis of the most uncertain and potentially significant parameters. The studied underground system has higher environmental impacts in all indicators and for all parameter values, mostly due to its higher material intensity. For both systems and all indicators the majority of impact occurs during cable production. Promising strategies for impact reduction are thus cable failure rate reduction for overhead and cable lifetime extension for underground systems.
NASA Astrophysics Data System (ADS)
Powell, James; Maise, George; Rather, John
2010-01-01
A new approach for the erection of rigid large scale structures in space-MIC (Magnetically Inflated Cable)-is described. MIC structures are launched as a compact payload of superconducting cables and attached tethers. After reaching orbit, the superconducting cables are energized with electrical current. The magnet force interactions between the cables cause them to expand outwards into the final large structure. Various structural shapes and applications are described. The MIC structure can be a simple flat disc with a superconducting outer ring that supports a tether network holding a solar cell array, or it can form a curved mirror surface that concentrates light and focuses it on a smaller region-for example, a high flux solar array that generates electric power, a high temperature receiver that heats H2 propellant for high Isp propulsion, and a giant primary reflector for a telescope for astronomy and Earth surveillance. Linear dipole and quadrupole MIC structures are also possible. The linear quadrupole structure can be used for magnetic shielding against cosmic radiation for astronauts, for example. MIC could use lightweight YBCO superconducting HTS (High Temperature Superconductor) cables, that can operate with liquid N2 coolant at engineering current densities of ~105 amp/cm2. A 1 kilometer length of MIC cable would weigh only 3 metric tons, including superconductor, thermal insulations, coolant circuits, and refrigerator, and fit within a 3 cubic meter compact package for launch. Four potential MIC applications are described: Solar-thermal propulsion using H2 propellant, space based solar power generation for beaming power to Earth, a large space telescope, and solar electric generation for a manned lunar base. The first 3 applications use large MIC solar concentrating mirrors, while the 4th application uses a surface based array of solar cells on a magnetically levitated MIC structure to follow the sun. MIC space based mirrors can be very large and light in weight. A 300 meter diameter MIC mirror in orbit for example, would weigh 20 metric tons and MIC structures can be easily developed and tested on Earth at small scale in existing evacuated chambers followed by larger scale tests in the atmosphere, using a vacuum tight enclosure on the small diameter superconducting cable to prevent air leakage into the evacuated thermal insulation around the superconducting cable.
Method and apparatus for electrical cable testing by pulse-arrested spark discharge
Barnum, John R.; Warne, Larry K.; Jorgenson, Roy E.; Schneider, Larry X.
2005-02-08
A method for electrical cable testing by Pulse-Arrested Spark Discharge (PASD) uses the cable response to a short-duration high-voltage incident pulse to determine the location of an electrical breakdown that occurs at a defect site in the cable. The apparatus for cable testing by PASD includes a pulser for generating the short-duration high-voltage incident pulse, at least one diagnostic sensor to detect the incident pulse and the breakdown-induced reflected and/or transmitted pulses propagating from the electrical breakdown at the defect site, and a transient recorder to record the cable response. The method and apparatus are particularly useful to determine the location of defect sites in critical but inaccessible electrical cabling systems in aging aircraft, ships, nuclear power plants, and industrial complexes.
14 CFR 25.1703 - Function and installation: EWIS.
Code of Federal Regulations, 2011 CFR
2011-01-01
... arc tracking phenomena. (c) The design and installation of the main power cables (including generator cables) in the fuselage must allow for a reasonable degree of deformation and stretching without failure...
14 CFR 25.1703 - Function and installation: EWIS.
Code of Federal Regulations, 2014 CFR
2014-01-01
... arc tracking phenomena. (c) The design and installation of the main power cables (including generator cables) in the fuselage must allow for a reasonable degree of deformation and stretching without failure...
14 CFR 25.1703 - Function and installation: EWIS.
Code of Federal Regulations, 2012 CFR
2012-01-01
... arc tracking phenomena. (c) The design and installation of the main power cables (including generator cables) in the fuselage must allow for a reasonable degree of deformation and stretching without failure...
14 CFR 25.1703 - Function and installation: EWIS.
Code of Federal Regulations, 2013 CFR
2013-01-01
... arc tracking phenomena. (c) The design and installation of the main power cables (including generator cables) in the fuselage must allow for a reasonable degree of deformation and stretching without failure...
Simultaneous Thermal and Gamma Radiation Aging of Cable Polymers
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fifield, Leonard S.; Liu, Shuaishuai; Bowler, Nicola
Polymers used in nuclear power plant electrical cable systems experience aging and degradation over time due to environmental stress including heat and gamma irradiation. Prediction of long-term cable performance has been based on results of short-term accelerated laboratory aging studies, but questions remain regarding the correlation of accelerated aging to long-term, in-plant aging. This work seeks to increase understanding of the combined effects of heat and radiation on cable polymer material aging toward addressing these questions.
External heating of electrical cables and auto-ignition investigation.
Courty, L; Garo, J P
2017-01-05
Electric cables are now extensively used for both residential and industrial applications. During more than twenty years, multi-scale approaches have been developed to study fire behavior of such cables that represents a serious challenge. Cables are rather complicated materials because they consist of an insulated part and jacket of polymeric materials. These polymeric materials can have various chemical structures, thicknesses and additives and generally have a char-forming tendency when exposed to heat source. In this work, two test methods are used for the characterization of cable pyrolysis and flammability. The first one permits the investigation of cable pyrolysis. A description of the cable mass loss is obtained, coupling an Arrhenius expression with a 1D thermal model of cables heating. Numerical results are successfully compared with experimental data obtained for two types of cable commonly used in French nuclear power plants. The second one is devoted to ignition investigations (spontaneous or piloted) of these cables. All these basic observations, measurements and modelling efforts are of major interest for a more comprehensive fire resistance evaluation of electric cables. Copyright © 2016 Elsevier B.V. All rights reserved.
Multiport power router and its impact on future smart grids
NASA Astrophysics Data System (ADS)
Kado, Yuichi; Shichijo, Daiki; Wada, Keiji; Iwatsuki, Katsumi
2016-07-01
We propose a Y configuration power router as a unit cell to easily construct a power delivery system that can meet many types of user requirements. The Y configuration power router controls the direction and magnitude of power flows between three ports regardless of DC or AC. We constructed a prototype three-way isolated DC/DC converter that is the core unit of the Y configuration power router. The electrical insulation between three ports assures safety and reliability for power network systems. We then tested the operation of power flow control. The experimental results revealed that our methodology based on a governing equation was appropriate to control the power flow of the three-way DC/DC converter. In addition, a distribution network composed of power routers had the ability to easily enable interchanges of electrical power between autonomous microgrid cells. We also explored the requirements for communication between energy routers to achieve dynamic adjustments of energy flows in a coordinated manner and their impact on resilient power grid systems.
Custom electronic subsystems for the laboratory telerobotic manipulator
NASA Technical Reports Server (NTRS)
Glassell, R. L.; Butler, P. L.; Rowe, J. C.; Zimmermann, S. D.
1990-01-01
The National Aeronautics and Space Administration (NASA) Space Station Program presents new opportunities for the application of telerobotic and robotic systems. The Laboratory Telerobotic Manipulator (LTM) is a highly advanced 7 degrees-of-freedom (DOF) telerobotic/robotic manipulator. It was developed and built for the Automation Technology Branch at NASA's Langley Research Center (LaRC) for work in research and to demonstrate ground-based telerobotic manipulator system hardware and software systems for future NASA applications in the hazardous environment of space. The LTM manipulator uses an embedded wiring design with all electronics, motor power, and control and communication cables passing through the pitch-yaw differential joints. This design requires the number of cables passing through the pitch/yaw joint to be kept to a minimum. To eliminate the cables needed to carry each pitch-yaw joint's sensor data to the VME control computers, a custom-embedded electronics package for each manipulator joint was developed. The electronics package collects and sends the joint's sensor data to the VME control computers over a fiber optic cable. The electronics package consist of five individual subsystems: the VME Link Processor, the Joint Processor and the Joint Processor power supply in the joint module, the fiber optics communications system, and the electronics and motor power cabling.
Evolution of low-profile and lightweight electrical connectors for soldier-worn applications
NASA Astrophysics Data System (ADS)
Gans, Eric; Lee, Kang; Jannson, Tomasz; Walter, Kevin
2011-06-01
In addition to military radios, modern warfighters carry cell phones, GPS devices, computers, and night-vision aids, all of which require electrical cables and connectors for data and power transmission. Currently each electrical device operates via independent cables using conventional cable and connector technology. Conventional cables are stiff and difficult to integrate into a soldier-worn garment. Conventional connectors are tall and heavy, as they were designed to ensure secure connections to bulkhead-type panels, and being tall, represent significant snag-hazards in soldier-worn applications. Physical Optics Corporation has designed a new, lightweight and low-profile electrical connector that is more suitable for body-worn applications and operates much like a standard garment snap. When these connectors are mated, the combined height is <0.3 in. - a significant reduction from the 2.5 in. average height of conventional connectors. Electrical connections can be made with one hand (gloved or bare) and blindly (without looking). Furthermore, POC's connectors are integrated into systems that distribute data or power from a central location on the soldier's vest, reducing the length and weight of the cables necessary to interconnect various mission-critical electronic systems. The result is a lightweight power/data distribution system offering significant advantages over conventional electrical connectors in soldier-worn applications.
Efficient Design in a DC to DC Converter Unit
NASA Technical Reports Server (NTRS)
Bruemmer, Joel E.; Williams, Fitch R.; Schmitz, Gregory V.
2002-01-01
Space Flight hardware requires high power conversion efficiencies due to limited power availability and weight penalties of cooling systems. The International Space Station (ISS) Electric Power System (EPS) DC-DC Converter Unit (DDCU) power converter is no exception. This paper explores the design methods and tradeoffs that were utilized to accomplish high efficiency in the DDCU. An isolating DC to DC converter was selected for the ISS power system because of requirements for separate primary and secondary grounds and for a well-regulated secondary output voltage derived from a widely varying input voltage. A flyback-current-fed push-pull topology or improved Weinberg circuit was chosen for this converter because of its potential for high efficiency and reliability. To enhance efficiency, a non-dissipative snubber circuit for the very-low-Rds-on Field Effect Transistors (FETs) was utilized, redistributing the energy that could be wasted during the switching cycle of the power FETs. A unique, low-impedance connection system was utilized to improve contact resistance over a bolted connection. For improved consistency in performance and to lower internal wiring inductance and losses a planar bus system is employed. All of these choices contributed to the design of a 6.25 KW regulated dc to dc converter that is 95 percent efficient. The methodology used in the design of this DC to DC Converter Unit may be directly applicable to other systems that require a conservative approach to efficient power conversion and distribution.
Federal Register 2010, 2011, 2012, 2013, 2014
2010-08-06
... Cable, LLC; Notice of Institution of Section 206 Investigation and Refund Effective Date July 30, 2010...-116-000, pursuant to section 206 of the Federal Power Act (FPA), 16 U.S.C. 824e, concerning the justness and reasonableness of rates proposed by Trans Bay Cable, LLC (Trans Bay) in [[Page 47589
47 CFR 76.610 - Operation in the frequency bands 108-137 and 225-400 MHz-scope of application.
Code of Federal Regulations, 2013 CFR
2013-10-01
... COMMISSION (CONTINUED) BROADCAST RADIO SERVICES MULTICHANNEL VIDEO AND CABLE TELEVISION SERVICE Technical... applicable to all MVPDs (cable and non-cable) transmitting carriers or other signal components carried at an average power level equal to or greater than 10−4 watts across a 25 kHz bandwidth in any 160 microsecond...
47 CFR 76.610 - Operation in the frequency bands 108-137 and 225-400 MHz-scope of application.
Code of Federal Regulations, 2010 CFR
2010-10-01
... COMMISSION (CONTINUED) BROADCAST RADIO SERVICES MULTICHANNEL VIDEO AND CABLE TELEVISION SERVICE Technical... applicable to all MVPDs (cable and non-cable) transmitting carriers or other signal components carried at an average power level equal to or greater than 10−4 watts across a 25 kHz bandwidth in any 160 microsecond...
47 CFR 76.610 - Operation in the frequency bands 108-137 and 225-400 MHz-scope of application.
Code of Federal Regulations, 2014 CFR
2014-10-01
... COMMISSION (CONTINUED) BROADCAST RADIO SERVICES MULTICHANNEL VIDEO AND CABLE TELEVISION SERVICE Technical... applicable to all MVPDs (cable and non-cable) transmitting carriers or other signal components carried at an average power level equal to or greater than 10−4 watts across a 25 kHz bandwidth in any 160 microsecond...
47 CFR 76.610 - Operation in the frequency bands 108-137 and 225-400 MHz-scope of application.
Code of Federal Regulations, 2012 CFR
2012-10-01
... COMMISSION (CONTINUED) BROADCAST RADIO SERVICES MULTICHANNEL VIDEO AND CABLE TELEVISION SERVICE Technical... applicable to all MVPDs (cable and non-cable) transmitting carriers or other signal components carried at an average power level equal to or greater than 10−4 watts across a 25 kHz bandwidth in any 160 microsecond...
NASA Technical Reports Server (NTRS)
Lebron, Ramon C.; Oliver, Angela C.; Bodi, Robert F.
1991-01-01
Power components hardware in support of the Space Station Freedom dc Electrical Power System were tested. One type of breadboard hardware tested is the dc Load Converter Unit, which constitutes the power interface between the electric power system and the actual load. These units are dc to dc converters that provide the final system regulation before power is delivered to the load. Three load converters were tested: a series resonant converter, a series inductor switchmode converter, and a switching full-bridge forward converter. The topology, operation principles, and tests results are described, in general. A comparative analysis of the three units is given with respect to efficiency, regulation, short circuit behavior (protection), and transient characteristics.
Space Station Freedom secondary power wiring requirements
NASA Technical Reports Server (NTRS)
Sawyer, C. R.
1994-01-01
Secondary power is produced by DDCU's (direct current to direct current converter units) and routed to and through secondary power distribution assemblies (SPDA's) to loads or tertiary distribution assemblies. This presentation outlines requirements of Space Station Freedom (SSF) EEE (electrical, electronic, and electromechanical) parts wire and the approved electrical wire and cable. The SSF PDRD (Program Definition and Requirements Document) language problems and resolution are reviewed. The cable routing to and from the SPDA's is presented as diagrams and the wire recommendations and characteristics are given.
Test Results of Selected Commercial DC/DC Converters under Cryogenic Temperatures - A Digest
NASA Technical Reports Server (NTRS)
Patterson, Richard; Hammoud, Ahmad
2010-01-01
DC/DC converters are widely used in space power systems in the areas of power management and distribution, signal conditioning, and motor control. Design of DC/DC converters to survive cryogenic temperatures will improve the power system performance, simplify design, and reduce development and launch costs. In this work, the performance of nine COTS modular, low-tomedium power DC/DC converters was investigated under cryogenic temperatures. The converters were evaluated in terms of their output regulation, efficiency, and input and output currents. At a given temperature, these properties were obtained at various input voltages and at different load levels. A summary on the performance of the tested converters was given. More comprehensive testing and in-depth analysis of performance under long-term exposure to extreme temperatures are deemed necessary to establish the suitability of these and other devices for use in the harsh environment of space exploration missions.
Integrated-Circuit Controller For Brushless dc Motor
NASA Technical Reports Server (NTRS)
Le, Dong Tuan
1994-01-01
Generic circuit performs commutation-logic and power-switching functions for control of brushless dc motor. Controller includes commutation-logic and associated control circuitry, power supply, and inverters containing power transistors. Major advantages of controller are size, weight, and power consumption can be made less than other brushless-dc-motor controllers.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Parise, G.; Rubino, G.
1995-12-31
The same basic principles, on which the methods of power cables protection against overloads are based, are summed up by different criteria and formulations within ANSI/IEEE and CENELEC/IEC publications. The studies carried out by the technical committees of these organizations have been examined and compared in order to point out not only their differences but also their complementary aspects. By arranging the two approaches, it has been possible to outline a third way to determine the admissible duration of overload currents and define intermediate criteria for the emergency ratings of cables and for the coordination of protective devices.
Integration of HTS Cables in the Future Grid of the Netherlands
NASA Astrophysics Data System (ADS)
Zuijderduin, R.; Chevtchenko, O.; Smit, J. J.; Aanhaanen, G.; Melnik, I.; Geschiere, A.
Due to increasing power demand, the electricity grid of the Netherlands is changing. The future transmission grid will obtain electrical power generated by decentralized renewable sources, together with large scale generation units located at the coastal region. In this way electrical power has to be distributed and transmitted over longer distances from generation to end user. Potential grid issues like: amount of distributed power, grid stability and electrical loss dissipation merit particular attention. High temperature superconductors (HTS) can play an important role in solving these grid problems. Advantages to integrate HTS components at transmission voltages are numerous: more transmittable power together with less emissions, intrinsic fault current limiting capability, lower ac loss, better control of power flow, reduced footprint, less magnetic field emissions, etc. The main obstacle at present is the relatively high price of HTS conductor. However as the price goes down, initial market penetration of several HTS components (e.g.: cables, fault current limiters) is expected by year 2015. In the full paper we present selected ways to integrate EHV AC HTS cables depending on a particular future grid scenario in the Netherlands.
NASA Astrophysics Data System (ADS)
Elangovan, D.; Archana, R.; Jayadeep, V. J.; Nithin, M.; Arunkumar, G.
2017-11-01
More than fifty percent Indian population do not have access to electricity in daily lives. The distance between the power generating stations and the distribution centers forms one of the main reasons for lack of electrification in rural and remote areas. Here lies the importance of decentralization of power generation through renewable energy resources. In the present world, electricity is predominantly powered by alternating current, but most day to day devices like LED lamps, computers and electrical vehicles, all run on DC power. By directly supplying DC to these loads, the number of power conversion stages was reduced, and overall system efficiency increases. Replacing existing AC network with DC is a humongous task, but with power electronic techniques, this project intends to implement DC grid at a household level in remote and rural areas. Proposed work was designed and simulated successfully for various loads amounting to 250 W through appropriate power electronic convertors. Maximum utilization of the renewable sources for domestic and commercial application was achieved with the proposed DC topology.
DC Microgrids Scoping Study. Estimate of Technical and Economic Benefits
DOE Office of Scientific and Technical Information (OSTI.GOV)
Backhaus, Scott N.; Swift, Gregory William; Chatzivasileiadis, Spyridon
Microgrid demonstrations and deployments are expanding in US power systems and around the world. Although goals are specific to each site, these microgrids have demonstrated the ability to provide higher reliability and higher power quality than utility power systems and improved energy utilization. The vast majority of these microgrids are based on AC power transfer because this has been the traditionally dominant power delivery scheme. Independently, manufacturers, power system designers and researchers are demonstrating and deploying DC power distribution systems for applications where the end-use loads are natively DC, e.g., computers, solid-state lighting, and building networks. These early DC applicationsmore » may provide higher efficiency, added flexibility, reduced capital costs over their AC counterparts. Further, when onsite renewable generation, electric vehicles and storage systems are present, DC-based microgrids may offer additional benefits. Early successes from these efforts raises a question - can a combination of microgrid concepts and DC distribution systems provide added benefits beyond what has been achieved individually?« less