WorldWideScience

Sample records for cell auxiliary power

  1. Solid Oxide Fuel Cell Auxiliary Power Unit

    International Nuclear Information System (INIS)

    Solid Oxide Fuel Cell (SOFC) is an attractive, efficient, clean source of power for transportation, military, and stationary applications. Delphi has pioneered its application as an auxiliary Power Unit (APU) for transportation. Delphi is also interested in marketing this technology for stationary applications. Its key advantages are high efficiency and compatibility with gasoline, natural gas and diesel fuel. It's consistent with mechanizations that support the trend to low emissions. Delphi is committed to working with customers and partners to bring this novel technology to market

  2. Development of a solid oxide fuel cell (SOFC) automotive auxiliary power unit (APU) fueled by gasoline

    International Nuclear Information System (INIS)

    This paper describes the design and the development progress of a 3 to 5 auxiliary power unit (APU) based on a gasoline fueled solid oxide fuel cell (SOFC). This fuel cell was supplied reformate gas (reactant) by a partial oxidation (POx) catalytic reformer utilizing liquid gasoline and designed by Delphi Automotive Systems. This reformate gas consists mainly of hydrogen, carbon monoxide and nitrogen and was fed directly in to the SOFC stack without any additional fuel reformer processing. The SOFC stack was developed by Global Thermoelectric and operates around 700oC. This automotive APU produces power to support future 42 volt vehicle electrical architectures and loads. The balance of the APU, designed by Delphi Automotive Systems, employs a packaging and insulation design to facilitate installation and operation on-board automobiles. (author)

  3. Auxiliary power unit based on a solid oxide fuel cell and fuelled with diesel

    Science.gov (United States)

    Lawrence, Jeremy; Boltze, Matthias

    An auxiliary power unit (APU) is presented that is fuelled with diesel, thermally self-sustaining, and based on a solid oxide fuel cell (SOFC). The APU is rated at 1 kW electrical, and can generate electrical power after a 3 h warm-up phase. System features include a "dry" catalytic partial oxidation (CPOX) diesel reformer, a 30 cell SOFC stack with an open cathode, and a porous-media afterburner. The APU does not require a supply of external water. The SOFC stack is an outcome of a development partnership with H.C. Starck GmbH and Fraunhofer IKTS, and is discussed in detail in an accompanying paper.

  4. PEMFC Optimization Strategy with Auxiliary Power Source in Fuel Cell Hybrid Vehicle

    Directory of Open Access Journals (Sweden)

    Tinton Dwi Atmaja

    2012-02-01

    Full Text Available Page HeaderOpen Journal SystemsJournal HelpUser You are logged in as...aulia My Journals My Profile Log Out Log Out as UserNotifications View (27 new ManageJournal Content SearchBrowse By Issue By Author By Title Other JournalsFont SizeMake font size smaller Make font size default Make font size largerInformation For Readers For Authors For LibrariansKeywords CBPNN Displacement FLC LQG/LTR Mixed PMA Ventilation bottom shear stress direct multiple shooting effective fuzzy logic geoelectrical method hourly irregular wave missile trajectory panoramic image predator-prey systems seawater intrusion segmentation structure development pattern terminal bunt manoeuvre Home About User Home Search Current Archives ##Editorial Board##Home > Vol 23, No 1 (2012 > AtmajaPEMFC Optimization Strategy with Auxiliary Power Source in Fuel Cell Hybrid VehicleTinton Dwi Atmaja, Amin AminAbstractone of the present-day implementation of fuel cell is acting as main power source in Fuel Cell Hybrid Vehicle (FCHV. This paper proposes some strategies to optimize the performance of Polymer Electrolyte Membrane Fuel Cell (PEMFC implanted with auxiliary power source to construct a proper FCHV hybridization. The strategies consist of the most updated optimization method determined from three point of view i.e. Energy Storage System (ESS, hybridization topology and control system analysis. The goal of these strategies is to achieve an optimum hybridization with long lifetime, low cost, high efficiency, and hydrogen consumption rate improvement. The energy storage system strategy considers battery, supercapacitor, and high-speed flywheel as the most promising alternative auxiliary power source. The hybridization topology strategy analyzes the using of multiple storage devices injected with electronic components to bear a higher fuel economy and cost saving. The control system strategy employs nonlinear control system to optimize the ripple factor of the voltage and the current

  5. Fuel Cell Auxiliary Power Study Volume 1: RASER Task Order 5

    Science.gov (United States)

    Mak, Audie; Meier, John

    2007-01-01

    This study evaluated the feasibility of a hybrid solid oxide fuel cell (SOFC) auxiliary power unit (APU) and the impact in a 90-passenger More-Electric Regional Jet application. The study established realistic hybrid SOFC APU system weight and system efficiencies, and evaluated the impact on the aircraft total weight, fuel burn, and emissions from the main engine and the APU during cruise, landing and take-off (LTO) cycle, and at the gate. Although the SOFC APU may be heavier than the current conventional APU, its weight disadvantage can be offset by fuel savings in the higher SOFC APU system efficiencies against the main engine bleed and extraction during cruise. The higher SOFC APU system efficiency compared to the conventional APU on the ground can also provide considerable fuel saving and emissions reduction, particularly at the gate, but is limited by the fuel cell stack thermal fatigue characteristic.

  6. The modeling of a standalone solid-oxide fuel cell auxiliary power unit

    Science.gov (United States)

    Lu, N.; Li, Q.; Sun, X.; Khaleel, M. A.

    In this research, a Simulink model of a standalone vehicular solid-oxide fuel cell (SOFC) auxiliary power unit (APU) is developed. The SOFC APU model consists of three major components: a controller model; a power electronics system model; and an SOFC plant model, including an SOFC stack module, two heat exchanger modules, and a combustor module. This paper discusses the development of the nonlinear dynamic models for the SOFC stacks, the heat exchangers and the combustors. When coupling with a controller model and a power electronic circuit model, the developed SOFC plant model is able to model the thermal dynamics and the electrochemical dynamics inside the SOFC APU components, as well as the transient responses to the electric loading changes. It has been shown that having such a model for the SOFC APU will help design engineers to adjust design parameters to optimize the performance. The modeling results of the SOFC APU heat-up stage and the output voltage response to a sudden load change are presented in this paper. The fuel flow regulation based on fuel utilization is also briefly discussed.

  7. Techno-economic analysis of fuel cell auxiliary power units as alternative to idling

    Science.gov (United States)

    Jain, Semant; Chen, Hsieh-Yeh; Schwank, Johannes

    This paper presents a techno-economic analysis of fuel-cell-based auxiliary power units (APUs), with emphasis on applications in the trucking industry and the military. The APU system is intended to reduce the need for discretionary idling of diesel engines or gas turbines. The analysis considers the options for on-board fuel processing of diesel and compares the two leading fuel cell contenders for automotive APU applications: proton exchange membrane fuel cell and solid oxide fuel cell. As options for on-board diesel reforming, partial oxidation and auto-thermal reforming are considered. Finally, using estimated and projected efficiency data, fuel consumption patterns, capital investment, and operating costs of fuel-cell APUs, an economic evaluation of diesel-based APUs is presented, with emphasis on break-even periods as a function of fuel cost, investment cost, idling time, and idling efficiency. The analysis shows that within the range of parameters studied, there are many conditions where deployment of an SOFC-based APU is economically viable. Our analysis indicates that at an APU system cost of 100 kW -1, the economic break-even period is within 1 year for almost the entire range of conditions. At 500 kW -1 investment cost, a 2-year break-even period is possible except for the lowest end of the fuel consumption range considered. However, if the APU investment cost is 3000 kW -1, break-even would only be possible at the highest fuel consumption scenarios. For Abram tanks, even at typical land delivered fuel costs, a 2-year break-even period is possible for APU investment costs as high as 1100 kW -1.

  8. Hovercraft auxiliary power units (APUs)

    Energy Technology Data Exchange (ETDEWEB)

    Russell, B.J.

    1983-08-01

    Auxiliary power units (APU) manufactured by British firms for use in hovercraft are characterized. Both diesel and gas-turbine APUs are found to be well suited to the demands of this application. The design features, dimensions, performance data, and installation requirements are discussed for the SS 90, SS 923, DA-1, BA-1, HM 5, and Gevaudan 9 APUs, as well as the TRS 18 gas-turbine smoke generator. The progress made in improving the fuel efficiency of gas turbines and reducing the weight of diesel engines is considered significant.

  9. A review of high-temperature polymer electrolyte membrane fuel-cell (HT-PEMFC)-based auxiliary power units for diesel-powered road vehicles

    Science.gov (United States)

    Liu, Yongfeng; Lehnert, Werner; Janßen, Holger; Samsun, Remzi Can; Stolten, Detlef

    2016-04-01

    This paper presents an extensive review of research on the development of auxiliary power units with enhanced reformate tolerance for high temperature polymer electrolyte membrane fuel cells (HT-PEMFCs). Developments in diesel reforming for fuel cells as auxiliary power units (APUs), single fuel cells and stacks and systems are outlined in detail and key findings are presented. Summaries of HT-PEMFC APU applications and start-up times for HT-PEMFC systems are then given. A summary of cooling HT-PEMFC stacks using a classic schematic diagram of a 24-cell HT-PEMFC stack, with a cooling plate for every third cell, is also presented as part of a stack analysis. Finally, a summary of CO tolerances for fuel cells is given, along with the effects of different CO volume fractions on polarization curves, the fraction of CO coverage, hydrogen coverage, anode overpotential and cell potential.

  10. Engineering aspects and hardware verification of a volume producable solid oxide fuel cell stack design for diesel auxiliary power units

    Science.gov (United States)

    Stelter, Michael; Reinert, Andreas; Mai, Björn Erik; Kuznecov, Mihail

    A solid oxide fuel cell (SOFC) stack module is presented that is designed for operation on diesel reformate in an auxiliary power unit (APU). The stack was designed using a top-down approach, based on a specification of an APU system that is installed on board of vehicles. The stack design is planar, modular and scalable with stamped sheet metal interconnectors. It features thin membrane electrode assemblies (MEAs), such as electrolyte supported cells (ESC) and operates at elevated temperatures around 800 °C. The stack has a low pressure drop in both the anode and the cathode to facilitate a simple system layout. An overview of the technical targets met so far is given. A stack power density of 0.2 kW l -1 has been demonstrated in a fully integrated, thermally self-sustaining APU prototype running with diesel and without an external water supply.

  11. Solid Oxide Fuel Cell Development for Auxiliary Power in Heavy Duty Vehicle Applications

    Energy Technology Data Exchange (ETDEWEB)

    Daniel T. Hennessy

    2010-06-15

    Changing economic and environmental needs of the trucking industry is driving the use of auxiliary power unit (APU) technology for over the road haul trucks. The trucking industry in the United States remains the key to the economy of the nation and one of the major changes affecting the trucking industry is the reduction of engine idling. Delphi Automotive Systems, LLC (Delphi) teamed with heavy-duty truck Original Equipment Manufacturers (OEMs) PACCAR Incorporated (PACCAR), and Volvo Trucks North America (VTNA) to define system level requirements and develop an SOFC based APU. The project defines system level requirements, and subsequently designs and implements an optimized system architecture using an SOFC APU to demonstrate and validate that the APU will meet system level goals. The primary focus is on APUs in the range of 3-5 kW for truck idling reduction. Fuels utilized were derived from low-sulfur diesel fuel. Key areas of study and development included sulfur remediation with reformer operation; stack sensitivity testing; testing of catalyst carbon plugging and combustion start plugging; system pre-combustion; and overall system and electrical integration. This development, once fully implemented and commercialized, has the potential to significantly reduce the fuel idling Class 7/8 trucks consume. In addition, the significant amounts of NOx, CO2 and PM that are produced under these engine idling conditions will be virtually eliminated, inclusive of the noise pollution. The environmental impact will be significant with the added benefit of fuel savings and payback for the vehicle operators / owners.

  12. Conceptual design and selection of a biodiesel fuel processor for a vehicle fuel cell auxiliary power unit

    Science.gov (United States)

    Specchia, S.; Tillemans, F. W. A.; van den Oosterkamp, P. F.; Saracco, G.

    Within the European project BIOFEAT (biodiesel fuel processor for a fuel cell auxiliary power unit for a vehicle), a complete modular 10 kW e biodiesel fuel processor capable of feeding a PEMFC will be developed, built and tested to generate electricity for a vehicle auxiliary power unit (APU). Tail pipe emissions reduction, increased use of renewable fuels, increase of hydrogen-fuel economy and efficient supply of present and future APU for road vehicles are the main project goals. Biodiesel is the chosen feedstock because it is a completely natural and thus renewable fuel. Three fuel processing options were taken into account at a conceptual design level and compared for hydrogen production: (i) autothermal reformer (ATR) with high and low temperature shift (HTS/LTS) reactors; (ii) autothermal reformer (ATR) with a single medium temperature shift (MTS) reactor; (iii) thermal cracker (TC) with high and low temperature shift (HTS/LTS) reactors. Based on a number of simulations (with the AspenPlus® software), the best operating conditions were determined (steam-to-carbon and O 2/C ratios, operating temperatures and pressures) for each process alternative. The selection of the preferential fuel processing option was consequently carried out, based on a number of criteria (efficiency, complexity, compactness, safety, controllability, emissions, etc.); the ATR with both HTS and LTS reactors shows the most promising results, with a net electrical efficiency of 29% (LHV).

  13. Auxiliary power unit for moving a vehicle

    Science.gov (United States)

    Akasam, Sivaprasad; Johnson, Kris W.; Johnson, Matthew D.; Slone, Larry M.; Welter, James Milton

    2009-02-03

    A power system is provided having at least one traction device and a primary power source configured to power the at least one traction device. In addition, the power system includes an auxiliary power source also configured to power the at least one traction device.

  14. Dynamic evaluation of low-temperature metal-supported solid oxide fuel cell oriented to auxiliary power units

    Science.gov (United States)

    Wang, Zhenwei; Berghaus, Jörg Oberste; Yick, Sing; Decès-Petit, Cyrille; Qu, Wei; Hui, Rob; Maric, Radenka; Ghosh, Dave

    A metal-supported solid oxide fuel cell (SOFC) composed of a Ni-Ce 0.8Sm 0.2O 2- δ (Ni-SDC) cermet anode and an SDC electrolyte was fabricated by suspension plasma spraying on a Hastelloy X substrate. The cathode, an Sm 0.5Sr 0.5CoO 3 (SSCo)-SDC composite, was screen-printed and fired in situ. The dynamic behaviour of the cell was measured while subjected to complete fuel shutoff and rapid start-up cycles, as typically encountered in auxiliary power units (APU) applications. A promising performance - with a maximum power density (MPD) of 0.176 W cm -2 at 600 °C - was achieved using humidified hydrogen as fuel and air as the oxidant. The cell also showed excellent resistance to oxidation at 600 °C during fuel shutoff, with only a slight drop in performance after reintroduction of the fuel. The Cr and Mn species in the Hastelloy X alloy appeared to be preferentially oxidized while the oxidation of nickel in the metallic substrate was temporarily alleviated. In rapid start-up cycles with a heating rate of 60 °C min -1, noticeable performance deterioration took place in the first two thermal cycles, and then continued at a much slower rate in subsequent cycles. A postmortem analysis of the cell suggested that the degradation was mainly due to the mismatch of the thermal expansion coefficient across the cathode/electrolyte interface.

  15. Study on Use of Fuel-Cell Auxiliary Power Units in Refrigerator Cars Employed for Delivery to Convenience Store

    Science.gov (United States)

    Katayama, Noboru; Kamiyama, Hideyuki; Kogoshi, Sumio; Kudo, Yusuke; Fukada, Takafumi; Ogawa, Makoto

    The use of fuel-cell auxiliary power units (FC-APU) in refrigerator cars employed delivery to for convenience store delivery has been studied. The delivery pattern is assumed to be a typical pattern that includes driving between convenience stores or between a delivery center and a convenience store, unloading, driver's lunch break. The M15 driving mode, which simulates the driving condition in urban areas, is used as the driving mode in the delivery pattern. The FC-APU system includes a proton-exchange membrane fuel cell (PEFC) module, an inverter, and DC/DC converter. Bench tests of the FC-APU are performed to determine the hydrogen fuel consumption rate and the energy efficiency; these values depend on the output power of the PEFC module. The calculated relationship between the output power and fuel consumption rate of a current used system, which consists of an alternator and a secondary battery, are used to estimate the energy efficiency of the current used system. On the basis of the measurement data in this study and the results for the model proposed by Brodric et al. [C. J. Brodrick et al., Trans. Res. D, vol 7, pp. 303 (2002)], the payback period is calculated. The results indicate that the payback period would be 2.1 years when the FC-APU operates at a load of 70%.

  16. Electrical start-up for diesel fuel processing in a fuel-cell-based auxiliary power unit

    Science.gov (United States)

    Samsun, Remzi Can; Krupp, Carsten; Tschauder, Andreas; Peters, Ralf; Stolten, Detlef

    2016-01-01

    As auxiliary power units in trucks and aircraft, fuel cell systems with a diesel and kerosene reforming capacity offer the dual benefit of reduced emissions and fuel consumption. In order to be commercially viable, these systems require a quick start-up time with low energy input. In pursuit of this end, this paper reports an electrical start-up strategy for diesel fuel processing. A transient computational fluid dynamics model is developed to optimize the start-up procedure of the fuel processor in the 28 kWth power class. The temperature trend observed in the experiments is reproducible to a high degree of accuracy using a dual-cell approach in ANSYS Fluent. Starting from a basic strategy, different options are considered for accelerating system start-up. The start-up time is reduced from 22 min in the basic case to 9.5 min, at an energy consumption of 0.4 kW h. Furthermore, an electrical wire is installed in the reformer to test the steam generation during start-up. The experimental results reveal that the generation of steam at 450 °C is possible within seconds after water addition to the reformer. As a result, the fuel processor can be started in autothermal reformer mode using the electrical concept developed in this work.

  17. A techno-economic comparison of fuel processors utilizing diesel for solid oxide fuel cell auxiliary power units

    Science.gov (United States)

    Nehter, Pedro; Hansen, John Bøgild; Larsen, Peter Koch

    Ultra-low sulphur diesel (ULSD) is the preferred fuel for mobile auxiliary power units (APU). The commercial available technologies in the kW-range are combustion engine based gensets, achieving system efficiencies about 20%. Solid oxide fuel cells (SOFC) promise improvements with respect to efficiency and emission, particularly for the low power range. Fuel processing methods i.e., catalytic partial oxidation, autothermal reforming and steam reforming have been demonstrated to operate on diesel with various sulphur contents. The choice of fuel processing method strongly affects the SOFC's system efficiency and power density. This paper investigates the impact of fuel processing methods on the economical potential in SOFC APUs, taking variable and capital cost into account. Autonomous concepts without any external water supply are compared with anode recycle configurations. The cost of electricity is very sensitive on the choice of the O/C ratio and the temperature conditions of the fuel processor. A sensitivity analysis is applied to identify the most cost effective concept for different economic boundary conditions. The favourite concepts are discussed with respect to technical challenges and requirements operating in the presence of sulphur.

  18. BIOFEAT: Biodiesel fuel processor for a vehicle fuel cell auxiliary power unit. Study of the feed system

    Science.gov (United States)

    Sgroi, M.; Bollito, G.; Saracco, G.; Specchia, S.

    An integrated auxiliary power unit (APU) based on a 10 kW e integrated biodiesel fuel processor has been designed and is being developed. Auto-thermal reforming (ATR) and thermal cracking (TC) were considered for converting the fuel into a hydrogen-rich gas suitable for PEM fuel cells. The fuel processor includes also a gas clean-up system that will reduce the carbon monoxide in the primary processor exit gas to below 10 ppm via a new heat-integrated CO clean-up unit, based on the assembly of catalytic heat exchange plates, so as to meet the operational requirements of a PEMFC stack. This article is devoted to the study and selection of the proper feed strategy for the primary fuel processor. Different pre-treatment and feed alternatives (e.g. based on nozzles or simple coils) were devised and tested for the ATR processors, which turned out to be the preferred primary processing route. A nozzle-based strategy was finally selected along with special recommendations about the constituent materials and the operating procedures to be adopted to avoid coking and nozzle corrosion as well as to allow a wide turn down ratio.

  19. Evaluation of Fuel Cell Auxiliary Power Units for Heavy-Duty Diesel Trucks

    OpenAIRE

    Brodrick, Christie-Joy; Lipman, Timothy; Farshchi, Mohammad; Lutsey, Nicholas; Dwyer, Harry; Sperling, Daniel; Gouse, S. William; King, Foy

    2002-01-01

    A large number of heavy-duty trucks idle a significant amount. Heavy-duty line-haul engines idle about 20-40% of the time the engine is running, depending on season and operation. Drivers idle engines to power climate control devices (e.g., heaters and air conditioners) and sleeper compartment accessories (e.g., refrigerators, microwave ovens, and televisions) and to avoid start-up problems in cold weather. Idling increases air pollution and energy use, as well as wear and tear on engines. Ef...

  20. Evaluation of Fuel Cell Auxiliary Power Units for Heavy-Duty Diesel Trucks

    OpenAIRE

    Brodrick, Christie-Joy; Lipman, Timothy; Farshchi, Mohammad; Lutsey, Nicholas P.; Dwyer, Harry A.; Sperling, Dan; Gouse, Bill; Harris, D Bruce; King, Foy G

    2002-01-01

    A large number of heavy-duty trucks idle a significant amount. Heavy-duty line-haul truck engines idle about 20-40% of the time the engine is running, depending on season and operation. Drivers idle engines to power climate control devices (e.g., heaters and air conditioners) and sleeper compartment accessories (e.g., refrigerators, microwave ovens, and televisions) and to avoid start-up problems in cold weather. Idling increases air pollution and energy use, as well as wear and tear on engin...

  1. Evaluation of Fuel Cell Auxiliary Power Units for Heavy-Duty Diesel Trucks

    OpenAIRE

    Brodrick, Christie-Joy; Lipman, Timothy; Farshchi, Mohammad; Lutsey, Nicholas; Dwyer, Harry; Sperling, Daniel; Gouse, S. William; King, Foy

    2002-01-01

    A large number of heavy-duty trucks idle a significant amount. Heavy-duty line-haul engines idle about 20-40% of the time the engine is running, depending on season and operation. Drivers idle engines to power climate control devices (e.g., heaters and air conditioners) and sleeper compartment accessories (e.g., refrigerators, microwave ovens, and televisions) and to avoid start-up problems in cold weather. Idling increases air pollution and energy use, as well as wear and tear on engines....

  2. Investigation of the Start-up Strategy for a Solid Oxide Fuel Cell Based Auxiliary Power Unit under Transient Conditions

    Directory of Open Access Journals (Sweden)

    Michael R. von Spakovsky

    2005-06-01

    Full Text Available

    A typical approach to the synthesis/design optimization of energy systems is to only use steady state operation and high efficiency (or low total life cycle cost at full load as the basis for the synthesis/design. Transient operation as reflected by changes in power demand, shut-down, and start-up are left as secondary tasks to be solved by system and control engineers once the synthesis/design is fixed. However, start-up and shut-down may be events that happen quite often and, thus, may be quite important in the creative process of developing the system. This is especially true for small power units used in transportation applications or for domestic energy supplies, where the load demand changes frequently and peaks in load of short duration are common. The duration of start-up is, of course, a major factor which must be considered since rapid system response is an important factor in determining the feasibility of solid oxide fuel cell (SOFC based auxiliary power units (APUs. Start-up and shut-down may also significantly affect the life span of the system due to thermal stresses on all system components. Therefore, a proper balance must be struck between a fast response and the costs of owning and operating the system so that start-up or any other transient process can be accomplished in as short a time as possible yet with a minimum in fuel consumption.

    In this research work we have been studying the effects of control laws and strategies and transients on system performance. The results presented in this paper are based on a set of transient models developed and implemented for the components of a 5 kWe net power SOFC based APU and for the high-fidelity system which results from their integration. The simulation results given below are for two different start-up approaches: one with steam recirculation and component pre-heating and the second without either. These start-up simulations were performed for fixed values of a number of

  3. Vacuum switchgear for power station auxiliary switchboards

    International Nuclear Information System (INIS)

    Sizewell B is the first UK power station in which vacuum switchgear is used for the auxiliary switchboards. Previously the 3.3kV, 6.6kV or 11kV switchgear has used air-break circuit breakers and fused air-break contactors, known as motor starting devices or fused switching devices (FSD). The use of vacuum interrupters is therefore a new technology in this application, although it has been established in the UK distribution network and in industrial installations from the mid 1970s. Vacuum switchgear was already in use in the USA for power station auxiliary switchgear at the time that it was proposed for Sizewell B. The Sizewell B high voltage auxiliary switchgear comprises eight Unit and Station Auxiliary Switchboards at 3.3kV and 11kV, and four 3.3kV Essential Switchboards for the essential safety related circuits, making a total of 65 circuit breakers plus FSD panels. (Author)

  4. Effects of auxiliary source connections in multichip power module

    DEFF Research Database (Denmark)

    Li, Helong; Munk-Nielsen, Stig; Beczkowski, Szymon;

    2016-01-01

    Auxiliary source bond wires and connections are widely used to in the power module with paralleled MOSFETs or IGBTs. This paper investigates the working mechanism and the effects of the auxiliary source connections in multichip power modules. It reveals that the auxiliary source connections cannot...

  5. 20--500 watt AMTEC auxiliary electric power system

    Energy Technology Data Exchange (ETDEWEB)

    Ivanenok, J.F. III; Sievers, R.K. [Advanced Modular Power Systems, Inc., Ann Arbor, MI (United States)

    1996-12-31

    Numerous design studies have been completed on Alkali Metal Thermal to Electric Converter (AMTEC) power systems for space applications demonstrating their substantial increase in performance. Recently design studies have been initiated to couple AMTEC power conversion with fossil fueled combustion systems. This paper describes the results of a Phase 1 SBIR effort to design an innovative, efficient, reliable, long life AMTEC Auxiliary Electric Power System (AEPS) for remote site applications (20--500 watts). The concept uses high voltage AMTEC cells, each containing 7 to 9 small electrolyte tubes, integrated with a combustor and recuperator. These multi-tube AMTEC cells are low cost, reliable, long life static converters. AMTEC technology is ideal for auxiliary electric power supplies that must operate reliably over a broad range of temperatures, fuel sources, power levels, and operational specifications. The simplicity, efficiency (20% systems) and modularity of this technology allow it to fill applications as varied as light-weight backpacks, remote site power supplies, and military base power. Phase 1 demonstrated the feasibility of a 20% system design, and showed that the development needs to focus on identifying long life AMTEC cell components, determining the AMTEC cell and system reliability, and demonstrating that a 20 watt AMTEC system is 3--5 times more efficient than existing systems for the same application.

  6. Dedicated auxiliary power units for Hybrid Electric Vehicles

    NARCIS (Netherlands)

    Mourad, S.; Weijer, C.J.T. van de

    1998-01-01

    The use of a dedicated auxiliary power unit is essential to utilize the potential that hybrid vehicles offer for efficient and ultra-clean transportation. An example of a hybrid project at the TNO Road-Vehicles Research Institute shows the development and the results of a dedicated auxiliary power u

  7. Orbiter Auxiliary Power Unit Flight Support Plan

    Science.gov (United States)

    Guirl, Robert; Munroe, James; Scott, Walter

    1990-01-01

    This paper discussed the development of an integrated Orbiter Auxiliary Power Unit (APU) and Improved APU (IAPU) Flight Suuport Plan. The plan identifies hardware requirements for continued support of flight activities for the Space Shuttle Orbiter fleet. Each Orbiter vehicle has three APUs that provide power to the hydraulic system for flight control surface actuation, engine gimbaling, landing gear deployment, braking, and steering. The APUs contain hardware that has been found over the course of development and flight history to have operating time and on-vehicle exposure time limits. These APUs will be replaced by IAPUs with enhanced operating lives on a vehicle-by-vehicle basis during scheduled Orbiter modification periods. This Flight Support Plan is used by program management, engineering, logistics, contracts, and procurement groups to establish optimum use of available hardware and replacement quantities and delivery requirements for APUs until vehicle modifications and incorporation of IAPUs. Changes to the flight manifest and program delays are evaluated relative to their impact on hardware availability.

  8. Indirect combustion noise of auxiliary power units

    Science.gov (United States)

    Tam, Christopher K. W.; Parrish, Sarah A.; Xu, Jun; Schuster, Bill

    2013-08-01

    Recent advances in noise suppression technology have significantly reduced jet and fan noise from commercial jet engines. This leads many investigators in the aeroacoustics community to suggest that core noise could well be the next aircraft noise barrier. Core noise consists of turbine noise and combustion noise. There is direct combustion noise generated by the combustion processes, and there is indirect combustion noise generated by the passage of combustion hot spots, or entropy waves, through constrictions in an engine. The present work focuses on indirect combustion noise. Indirect combustion noise has now been found in laboratory experiments. The primary objective of this work is to investigate whether indirect combustion noise is also generated in jet and other engines. In a jet engine, there are numerous noise sources. This makes the identification of indirect combustion noise a formidable task. Here, our effort concentrates exclusively on auxiliary power units (APUs). This choice is motivated by the fact that APUs are relatively simple engines with only a few noise sources. It is, therefore, expected that the chance of success is higher. Accordingly, a theoretical model study of the generation of indirect combustion noise in an Auxiliary Power Unit (APU) is carried out. The cross-sectional areas of an APU from the combustor to the turbine exit are scaled off to form an equivalent nozzle. A principal function of a turbine in an APU is to extract mechanical energy from the flow stream through the exertion of a resistive force. Therefore, the turbine is modeled by adding a negative body force to the momentum equation. This model is used to predict the ranges of frequencies over which there is a high probability for indirect combustion noise generation. Experimental spectra of internal pressure fluctuations and far-field noise of an RE220 APU are examined to identify anomalous peaks. These peaks are possible indirection combustion noise. In the case of the

  9. Auxiliary pattern for cell-based OPC

    Science.gov (United States)

    Kahng, Andrew B.; Park, Chul-Hong

    2006-10-01

    The runtime of model-based optical proximity correction (OPC) tools has grown unacceptably with each successive technology generation, and has emerged as one of the major bottlenecks for turnaround time (TAT) of IC data preparation and manufacturing. The cell-based OPC approach improves runtime by performing OPC once per cell definition as opposed to once per cell instantiation in the layout. However, cell-based OPC does not comprehend inter-cell optical interactions that affect feature printability in a layout context. In this work, we propose auxiliary pattern-enabled cell-based OPC which can minimize the CD differences between cell-based OPC and model-based OPC. To enable effective insertion of auxiliary pattern (AP) in the design, we also propose a post-placement optimization of a standard cell block with respect to detailed placement. By dynamic programming-based placement perturbation, we achieve 100% AP applicability in designs with placement utilizations of cell-based OPC with AP can match gate edge placement error (EPE) count of model-based OPC within 4%. This is an improvement of 90%, on average, over cell-based OPC without APs. The AP-based OPC approach can reduce OPC runtimes versus model-based OPC by up to 40X in our benchmark designs. We can also achieve reduction of GDSII file size and ORC runtimes due to hierarchy maintenance of cell-based OPC.

  10. Power consumption of the ASCV and auxiliary equipment

    DEFF Research Database (Denmark)

    Pedersen, Knud Ole Helgesen; Pedersen, Jørgen Kaas

    1998-01-01

    Operating an ASCV requires power - to cover the losses in the ASCV itself and to run auxiliary equipment. It is necessary to take this power consumption into account when considering the economical aspects of installing an ASCV.Field measurements of this consumption of the ASCV in Rejsby Hede are...

  11. Space Shuttle Orbiter auxiliary power unit status

    Science.gov (United States)

    Reck, M.; Loken, G.; Horton, J.; Lukens, W.; Scott, W.; Baughman, J.; Bauch, T.

    An overview of the United States Space Shuttle Orbiter APU, which provides power to the Orbiter vehicle hydraulic system, is presented. Three complete APU systems, each with its own separate fuel system, supply power to three dedicated hydraulic systems. These in turn provide power to all Orbiter vehicle critical flight functions including launch, orbit, reentry, and landing. The basic APU logic diagram is presented. The APU includes a hydrazine-powered turbine that drives a hydraulic pump and various accessories through a high-speed gearbox. The APU also features a sophisticated thermal management system designed to ensure safe and reliable operation in the various launch, orbit, reentry, and landing environments.

  12. 40 CFR 1033.510 - Auxiliary power units.

    Science.gov (United States)

    2010-07-01

    ... locomotive is equipped with an auxiliary power unit (APU) that operates during an idle shutdown mode, you must account for the APU's emissions rates as specified in this section, unless the APU is part of an... emission rate (g/hr) as specified in § 1033.530. Add the APU emission rate (g/hr) that you determine...

  13. Green Propulsion Auxiliary Power Unit Demonstration at MSFC

    Science.gov (United States)

    Robinson, Joel W.

    2014-01-01

    MSFC has embarked on use of green propellant replacement of hydrazine for a variety of applications. This paper focused on activities for auxiliary power unit but MSFC is actively investigating use of green propellants for thruster applications. MSFC is interested in partnership with the international community to address the infusion of green propellant into greater use.

  14. Compact propane fuel processor for auxiliary power unit application

    Science.gov (United States)

    Dokupil, M.; Spitta, C.; Mathiak, J.; Beckhaus, P.; Heinzel, A.

    With focus on mobile applications a fuel cell auxiliary power unit (APU) using liquefied petroleum gas (LPG) is currently being developed at the Centre for Fuel Cell Technology (Zentrum für BrennstoffzellenTechnik, ZBT gGmbH). The system is consisting of an integrated compact and lightweight fuel processor and a low temperature PEM fuel cell for an electric power output of 300 W. This article is presenting the current status of development of the fuel processor which is designed for a nominal hydrogen output of 1 k Wth,H2 within a load range from 50 to 120%. A modular setup was chosen defining a reformer/burner module and a CO-purification module. Based on the performance specifications, thermodynamic simulations, benchmarking and selection of catalysts the modules have been developed and characterised simultaneously and then assembled to the complete fuel processor. Automated operation results in a cold startup time of about 25 min for nominal load and carbon monoxide output concentrations below 50 ppm for steady state and dynamic operation. Also fast transient response of the fuel processor at load changes with low fluctuations of the reformate gas composition have been achieved. Beside the development of the main reactors the transfer of the fuel processor to an autonomous system is of major concern. Hence, concepts for packaging have been developed resulting in a volume of 7 l and a weight of 3 kg. Further a selection of peripheral components has been tested and evaluated regarding to the substitution of the laboratory equipment.

  15. 14 CFR 33.96 - Engine tests in auxiliary power unit (APU) mode.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Engine tests in auxiliary power unit (APU... Engine tests in auxiliary power unit (APU) mode. If the engine is designed with a propeller brake which... in operation, and remain stopped during operation of the engine as an auxiliary power unit (“APU...

  16. Auxiliary quasi-resonant dc tank electrical power converter

    Science.gov (United States)

    Peng, Fang Z.

    2006-10-24

    An auxiliary quasi-resonant dc tank (AQRDCT) power converter with fast current charging, voltage balancing (or charging), and voltage clamping circuits is provided for achieving soft-switched power conversion. The present invention is an improvement of the invention taught in U.S. Pat. No. 6,111,770, herein incorporated by reference. The present invention provides faster current charging to the resonant inductor, thus minimizing delay time of the pulse width modulation (PWM) due to the soft-switching process. The new AQRDCT converter includes three tank capacitors or power supplies to achieve the faster current charging and minimize the soft-switching time delay. The new AQRDCT converter further includes a voltage balancing circuit to charge and discharge the three tank capacitors so that additional isolated power supplies from the utility line are not needed. A voltage clamping circuit is also included for clamping voltage surge due to the reverse recovery of diodes.

  17. Comparative LCA of methanol-fuelled SOFCs as auxiliary power systems on-board ships

    International Nuclear Information System (INIS)

    Fuel cells own the potential for significant environmental improvements both in terms of air quality and climate protection. Through the use of renewable primary energies, local pollutant and greenhouse gas emissions can be significantly minimized over the full life cycle of the electricity generation process, so that marine industry accounts renewable energy as its future energy source. The aim of this paper is to evaluate the use of methanol in Solid Oxide Fuel Cells (SOFC), as auxiliary power systems for commercial vessels, through Life Cycle Assessment (LCA). The LCA methodology allows the assessment of the potential environmental impact along the whole life cycle of the process. The unit considered is a 20 kWel fuel cell system. In a first part of the study different fuel options have been compared (methanol, bio-methanol, natural gas, hydrogen from cracking, electrolysis and reforming), then the operation of the cell fed with methanol has been compared with the traditional auxiliary power system, i.e. a diesel engine. The environmental benefits of the use of fuel cells have been assessed considering different impact categories. The results of the analysis show that fuel production phase has a strong influence on the life cycle impacts and highlight that feeding with bio-methanol represents a highly attractive solution from a life cycle point of view. The comparison with the conventional auxiliary power system shows extremely lower impacts for SOFCs.

  18. Green Propulsion Auxiliary Power Unit Demonstration at MSFC

    Science.gov (United States)

    Robinson, Joel W.

    2014-01-01

    In 2012, the National Aeronautics & Space Administration (NASA) Space Technology Mission Directorate (STMD) began the process of building an integrated technology roadmap, including both technology pull and technology push strategies. Technology Area 1 (TA-01)1 for Launch Propulsion Systems is one of fourteen TAs that provide recommendations for the overall technology investment strategy and prioritization of NASA's space technology activities. Identified within TA-01 was the need for a green propulsion auxiliary power unit (APU) for hydraulic power by 2015. Engineers led by the author at the Marshall Space Flight Center (MSFC) have been evaluating green propellant alternatives and have begun the development of an APU test bed to demonstrate the feasibility of use. NASA has residual APU assets remaining from the retired Space Shuttle Program. Likewise, the F-16 Falcon fighter jet also uses an Emergency Power Unit (EPU) that has similar characteristics to the NASA hardware. Both EPU and APU components have been acquired for testing at MSFC. This paper will summarize the status of the testing efforts of green propellant from the Air Force Research Laboratory (AFRL) propellant AFM315E based on hydroxyl ammonium nitrate (HAN) with these test assets.

  19. Development and design of experiments optimization of a high temperature proton exchange membrane fuel cell auxiliary power unit with onboard fuel processor

    Science.gov (United States)

    Karstedt, Jörg; Ogrzewalla, Jürgen; Severin, Christopher; Pischinger, Stefan

    In this work, the concept development, system layout, component simulation and the overall DOE system optimization of a HT-PEM fuel cell APU with a net electric power output of 4.5 kW and an onboard methane fuel processor are presented. A highly integrated system layout has been developed that enables fast startup within 7.5 min, a closed system water balance and high fuel processor efficiencies of up to 85% due to the recuperation of the anode offgas burner heat. The integration of the system battery into the load management enhances the transient electric performance and the maximum electric power output of the APU system. Simulation models of the carbon monoxide influence on HT-PEM cell voltage, the concentration and temperature profiles within the autothermal reformer (ATR) and the CO conversion rates within the watergas shift stages (WGSs) have been developed. They enable the optimization of the CO concentration in the anode gas of the fuel cell in order to achieve maximum system efficiencies and an optimized dimensioning of the ATR and WGS reactors. Furthermore a DOE optimization of the global system parameters cathode stoichiometry, anode stoichiometry, air/fuel ratio and steam/carbon ratio of the fuel processing system has been performed in order to achieve maximum system efficiencies for all system operating points under given boundary conditions.

  20. Green Propulsion Auxiliary Power Unit Demonstration at MSFC

    Science.gov (United States)

    Robinson, Joel W.; Beckel, Steve

    2014-01-01

    In 2012, the National Aeronautics & Space Administration (NASA) Space Technology Mission Directorate (STMD) began the process of building an integrated technology roadmap, including both technology pull and technology push strategies. Technology Area 1 (TA-01) for Launch Propulsion Systems is one of fourteen TA's that provide recommendations for the overall technology investment strategy and prioritization of NASA's space technology activities. Identified within TA-01 was the need for a green propulsion auxiliary power unit (APU) for hydraulic power by 2015. Engineers led by the author at the Marshall Space Flight Center (MSFC) have been evaluating green propellant alternatives and have begun the development of an APU testbed to demonstrate the feasibility of use. NASA has residual APU assets remaining from the retired Space Shuttle Program. Likewise, the F-16 Falcon fighter jet also uses an Emergency Power Unit (EPU) that has similar characteristics to the NASA hardware. Both EPU's and APU components have been acquired for testing at MSFC. In concert with this effort, ATK has been developing green propellant technology based on the Swedish Space Corp ECAPS LMP-103S propellant. Propellant blending and test facilities have been established at ATK's Elkton MD facility with the intent to provide suitable propellant blends for application to green APU systems as well as thrusters. This paper will summarize the status of the testing efforts with ATK for use of the green propellant LMP-103S based on ammonium dinitramide and use of the Air Force Research Laboratory (AFRL) propellant AF-M315E based on hydroxyl ammonium nitrate with these test assets.

  1. Start-up of a power unit of a thermal power plant auxiliary system with supply from a hydropower plant

    OpenAIRE

    Zbigniew Lubośny; Krzysztof Dobrzyński; Jacek Klucznik

    2013-01-01

    This article discusses the issues related to a power unit of a thermal power plant start-up with the use of a hydropower plant. Hydropower plant can supply and will enable start-up of auxiliary equipment in a power unit of a thermal power plant. Due to high capacity of auxiliary drives, startup of auxiliaries in a thermal power plant after blackout (and boiler shutdown) is not possible from emergency energy sources in the power plant. In such a case an external electricity source with high ca...

  2. Start-up of a power unit of a thermal power plant auxiliary system with supply from a hydropower plant

    Directory of Open Access Journals (Sweden)

    Zbigniew Lubośny

    2013-09-01

    Full Text Available This article discusses the issues related to a power unit of a thermal power plant start-up with the use of a hydropower plant. Hydropower plant can supply and will enable start-up of auxiliary equipment in a power unit of a thermal power plant. Due to high capacity of auxiliary drives, startup of auxiliaries in a thermal power plant after blackout (and boiler shutdown is not possible from emergency energy sources in the power plant. In such a case an external electricity source with high capacity is required.

  3. Model-based prediction of suitable operating range of a SOFC for an Auxiliary Power Unit

    Science.gov (United States)

    Pfafferodt, Matthias; Heidebrecht, Peter; Stelter, Michael; Sundmacher, Kai

    This paper presents a one-dimensional steady state model of a solid oxide fuel cell (SOFC) to be used in an Auxiliary Power Unit (APU). The fuel cell is fed a prereformed gas from an external autothermic reformer. In addition to the three electrochemical reactions (reduction of oxygen at the cathode, oxidation of hydrogen and carbon monoxide at the anode) the water-gas shift reaction and the methane steam reforming reaction are taken into account in the anode channel. The model predicts concentrations and temperatures and uses an equivalent circuit approach to describe the current-voltage characteristics of the cell. The model equations are presented and their implementation into the commercial mathematical software FEMLAB is discussed. An application of this model is used to determine suitable operating parameters with respect to optimum performance and allowable temperature.

  4. Disturbance in the power system caused by auxiliary DC installation failure of switchyard

    Energy Technology Data Exchange (ETDEWEB)

    Mesic, M. [HEP Transmission System Operator, Zagreb (Croatia); Tesnjak, S.; Skok, S. [Zagreb Univ. (Croatia). Faculty of Electrical Engineering and Computing

    2008-07-01

    Auxiliary direct current (DC) installation failures can lead to outages in power plants and compromise the security of power systems. In this study, a simplified stationary model was used to simulate an auxiliary DC installation in a switchyard. The aim of the study was to evaluate new International Electrotechnical Commission (IEC) standards for auxiliary DC installation dimensioning and analysis. Criteria included the dimensioning and selection of batteries; the calculation of conductor heating; voltage drop calculations; conductor squares in relation to permanent currents; and the evaluation of protection elements. The new standards were compared with the previous auxiliary system installation methodology. Results of the study suggested that the new standard has introduced significant improvements in short circuit current calculation. Laboratory tests for the measurement of short circuits showed that the active network has less of an impact on the auxiliary system than previous measuring methods. Alterations to the IEC standard will be required as a result of limitations to the short circuit current and new rectifier technology. Results of the study will be used to develop a new model and scheme for dimensioning and analyzing auxiliary DC installations. 9 refs., 4 tabs., 5 figs.

  5. Using auxiliary gas power for CCS energy needs in retrofitted coal power plants

    OpenAIRE

    Bashadi, Sarah O.; Herzog, Howard J.

    2011-01-01

    Adding post-combustion capture technology to existing coal-fired power plants is being considered as a near-term option for mitigating CO[subscript 2] emissions. To supply the thermal energy needed for CO[subscript 2] capture, much of the literature proposes thermal integration of the existing coal plant’s steam cycle with the capture process’ stripper reboiler. This paper examines the option of using an auxiliary natural gas turbine plant to meet the energetic demands of carbon capture and c...

  6. ASCERTAINMENT OF ELECTRIC-SUPPLY SCHEMES RELIABILITY FOR THE ATOMIC POWER PLANT AUXILIARIES

    Directory of Open Access Journals (Sweden)

    A. L. Starzhinskij

    2015-01-01

    Full Text Available The paper completes ascertainment of electrical-supply scheme reliability for the auxiliaries of a nuclear power plant. Thereat the author considers the system behavior during the block normal operation, carrying out current maintenance, and capital repairs in combination with initiating events. The initiating events for reactors include complete blackout, i.e. the loss of outside power supply (normal and reserve; emergency switching one of the working turbogenerators; momentary dumping the normal rating to the level of auxiliaries with seating the cutout valve of one turbo-generator. The combination of any initiating event with the repairing mode in case of one of the system elements failure should not lead to blackout occurrence of more than one system of the reliable power supply. This requirement rests content with the help of the reliable power supply system self-dependence (electrical and functional and the emergency power-supply operational autonomy (diesel generator and accumulator batteries.The reliability indicators of the power supply system for the nuclear power plant auxiliaries are the conditional probabilities of conjoined blackout of one, two, and three sections of the reliable power supply conditional upon an initiating event emerging and the blackout of one, two, and three reliable power-supply sections under the normal operational mode. Furthermore, they also are the blackout periodicity of one and conjointly two, three, and four sections of normal operation under the block normal operational mode. It is established that the blackout of one bus section of normal operation and one section of reliable power-supply system of the auxiliaries that does not lead to complete blackout of the plant auxiliaries may occur once in three years. The probability of simultaneous power failure of two or three normal-operation sections and of two reliable power-supply sections during the power plant service life is unlikely.

  7. Multicriteria optimization of the investment in the auxiliary services of thermal power plants: A case study

    International Nuclear Information System (INIS)

    Highlights: • A multiobjective optimization model to improve the efficiency of auxiliary services. • Economic (investment and NPV) and energy saving criteria are considered. • Evolutionary multiobjective optimization is used for solving the problem with a DM. • A case study based on a real 1100 MW coal-fired power plant is considered. • Results show very profitable solutions from the economic and energy points of view. - Abstract: Thermal power plants have traditionally operated at rated power as base load, but nowadays they operate at partial loads because of the new situation of the electricity market. These plants have raised their auxiliary services consumption because, in most of the cases, the auxiliaries were not designed to efficiently operate at partial loads. This paper presents a multiple criteria study about the efficiency improvement of the auxiliary services. We consider the economic investment and the net present value, as economic criteria, together with the energy saving criterion. In the multiobjective model proposed, the energy model is validated using several measures taken in a 1100 megawatts coal power plant. Besides, the multiobjective problem associated to the case study considered is solved using evolutionary multiobjective optimization and considering preference information. The results obtained conclude that a significant efficiency improvement of the auxiliary services can be achieved by means of the improvement strategies considered. Indeed, the high net present values reached indicate that the investments required by the different solutions are really profitable from the economic perspective. Therefore, investing money in the efficiency improvement of the auxiliary services represents a very profitable option for improving the operation of power plants at partial loads

  8. Development and implementation of thermal signature testing protocol of auxiliary power unit (APU) and diesel tractor

    Science.gov (United States)

    Jenkins, Chelsea L.; Bourne, Stefanie M.; Rowley, Matthew J.; Miles, Jonathan J.

    2004-04-01

    Thermal signature may be one of the defining factors in determining the applicability of fuel cell auxiliary power unit (APU) technology in military applications. Thermal characterization is important for military applications given that identification and detection may be accomplished through observation of its thermal signature. The operating modes and power takeoff operations of a vehicle will likely determine the thermal profile. The objective of our study was to develop and implement a protocol for quantifying the thermal characteristics of a methanol fuel cell and an idling tractor engine under representative characteristic operations. APU thermal characteristics are a special case for which standardized testing procedures do not presently exist. A customized testing protocol was developed and applied that is specific to an APU-equipped vehicle. Initial testing was conducted on the methanol APU-equipped Freightliner tractor using a high-performance radiometric infrared system. The APU profile calls for a series of infrared images to be collected at three different viewing angles and two different elevations under various loads. The diesel engine was studied in a similar fashion using seven different viewing angles and two different elevations. Raw data collected according to the newly developed methodology provided the opportunity for computer analysis and thermal profiling of both the fuel cell and the diesel engine.

  9. Strategic analysis of a manufacturing company and the North American auxiliary power unit market

    OpenAIRE

    Fisher, Craig B.

    2005-01-01

    Power Systems has been the leader in the truck auxiliary power unit business since 2000 and has been making significant advancements in the price of the product as well as its reliability and robustness. Unfortunately the reliability and robustness requirement is increasing further and the profit margin is shrinking to the point that Power Systems needs to undertake a new product development program. The new product offering will result in zero increase in the price to the customer but provid...

  10. Performance of turbine auxiliaries and service systems at Rajasthan Atomic Power Station

    International Nuclear Information System (INIS)

    Performance of the turbine auxiliaries and service systems at the Rajasthan Atomic Power Station, India are described. Some of the specific problems encountered in connection with the feed water, turbine governing and common services like compressed air, chilled water, water treatment and chlorination systems are outlined. (K.B.)

  11. Analysis of design of auxiliary system of Booshehr Nuclear Power Plant

    International Nuclear Information System (INIS)

    Power plant's internal auxiliary system has an important role in its safety operation. Because of the decay heat and safety aspects in the nuclear power plants, this role is more important. In this thesis, operation of the nuclear power plant with PWR reactor is studied and deferent nuclear systems described. In the next section all electrical loads in the Booshehr Nuclear Power Plant identified and feeding methods of each load is determined. by use of the single line diagram of the internal auxiliary system, the nominal rating of all electrical devices as transformers, inverters, Ups, diesel generators and etc. is determined. In the following, short circuit calculations performed and by above conclusion, rating values of circuit breakers is determined. At last the starting problems of electrical motors is studied and the results of motor's behavior at starting moment is discussed

  12. A reliability centered maintenance model applied to the auxiliary feedwater system of a nuclear power plant

    International Nuclear Information System (INIS)

    The main objective of maintenance in a nuclear power plant is to assure that structures, systems and components will perform their design functions with reliability and availability in order to obtain a safety and economic electric power generation. Reliability Centered Maintenance (RCM) is a method of systematic review to develop or optimize Preventive Maintenance Programs. This study presents the objectives, concepts, organization and methods used in the development of RCM application to nuclear power plants. Some examples of this application are included, considering the Auxiliary Feedwater System of a generic two loops PWR nuclear power plant of Westinghouse design. (author)

  13. Power Conversion System Strategies for Fuel Cell Vehicles

    Institute of Scientific and Technical Information of China (English)

    Kaushik Rajashekara

    2005-01-01

    Power electronics is an enabling technology for the development of environmental friendly fuel cell vehicles, and to implement the various vehicle electrical architectures to obtain the best performance. In this paper, power conversion strategies for propulsion and auxiliary power unit applications are described. The power electronics strategies for the successful development of the fuel cell vehicles are presented. The fuel cell systems for propulsion and for auxiliary power unit applications are also discussed.

  14. Equipment Reliability Improvement for Koeberg Nuclear Power Plant Auxiliary Feedwater System

    International Nuclear Information System (INIS)

    This paper investigated how the performance of the Koeberg Auxiliary Feedwater System could be improved using the 'maintenance rule'. As a conclusion, this paper figured out AFWS pumps and the TDP control circuit need special attention in improving the reliability of the AFWS, this lead to an improved maintenance strategy for the system. The purpose of this study is to apply maintenance rule to enhance the Auxiliary Feedwater System (AFWS) maintenance strategy at Koeberg Nuclear Power Plant (KNPP). Currently, Koeberg AFWS health status is red, needing an improvement. This study seeks to use maintenance rule to identify components that enable AFWS to fulfill its essential functions so as to focus maintenance resources and have the greatest beneficial impact on improving reliability and availability of the system

  15. STS-31 Discovery, OV-103, auxiliary power unit 1 (APU-1) controller

    Science.gov (United States)

    1990-01-01

    The controller for Discovery's, Orbiter Vehicle (OV) 103's, auxiliary power unit 1 (APU-1) is documented before removal following the launch scrub on 04-10-90. The controller weighs about 15 pounds and controls the speed of the APU. It was flown to the vendor, Sundstrand Corp., Rockford, Illinois, for analysis and testing. Launch of OV-103 on mission STS-31 has been rescheduled for 04-24-90 following the successful replacement of the APU-1 and the recharging of the Hubble Space Telescope's (HST's) nickel-hydrogen batteries. View provided by the Kennedy Space Center (KSC) with alternate KSC number KSC-90PC-663.

  16. On the switching of NPP power unit transformers from auxiliary network

    International Nuclear Information System (INIS)

    In order to clarify the parameters of direct transformer connection the oscillography of a number of parameters of Zaporozhe NPP network and generators was performed, when switching the 1000 MW power unit transformer complex with 750 kV buses. The complex of transformers consisted of three single-phase 787/24 kV ORts-417000/750-77 type transformers and two auxiliary 24/6.3/6.3 kV of TRDNS-63000/35-72 type tramsformers connected to their 24 kV windings. It is shown that generator excitation forcing conditions arise for several seconds when applying voltage to a power unit step-up transformer through closure of the switch onto NPP high-voltage buses due to high jumps of magnetizing current. A technique of switching power unit transformer through application of voltage from 6 kV auxiliary section with subsequent connection to NPP high-voltage buses via a short-term mode of parallel operation, is mastered

  17. Diesel Fueled SOFC for Class 7/Class 8 On-Highway Truck Auxiliary Power

    Energy Technology Data Exchange (ETDEWEB)

    Vesely, Charles John-Paul [Cummins Power Generation; Fuchs, Benjamin S. [Cummins Power Generation; Booten, Chuck W. [Protonex Technology, LLC

    2010-03-31

    The following report documents the progress of the Cummins Power Generation (CPG) Diesel Fueled SOFC for Class 7/Class 8 On-Highway Truck Auxiliary Power (SOFC APU) development and final testing under the U.S. Department of Energy (DOE) Energy Efficiency and Renewable Energy (EERE) contract DE-FC36-04GO14318. This report overviews and summarizes CPG and partner development leading to successful demonstration of the SOFC APU objectives and significant progress towards SOFC commercialization. Significant SOFC APU Milestones: Demonstrated: Operation meeting SOFC APU requirements on commercial Ultra Low Sulfur Diesel (ULSD) fuel. SOFC systems operating on dry CPOX reformate. Successful start-up and shut-down of SOFC APU system without inert gas purge. Developed: Low cost balance of plant concepts and compatible systems designs. Identified low cost, high volume components for balance of plant systems. Demonstrated efficient SOFC output power conditioning. Demonstrated SOFC control strategies and tuning methods.

  18. Hydrogen environment embrittlement of turbine disk alloys. [for space shuttle auxiliary power unit

    Science.gov (United States)

    Gray, H. R.; Joyce, J. P.

    1976-01-01

    Astroloy and V-57, two candidate turbine disk alloys for the auxiliary power unit (APU) of the space shuttle propulsion and power system were tested for their resistance to embrittlement in hydrogen environments. Samples of both these nickel-base alloys were subjected to notch and smooth tensile testing and to creep testing in hydrogen. The high resistance exhibited by Astroloy forgings to embrittlement by hydrogen is attributed to the microstructure produced by forging and also to the special heat treatment schedule. V-57 turbine disks successfully completed short-time performance testing in the experimental APU. The use of the Astroloy, however, would permit increasing turbine inlet temperature and the rotational speed beyond those possible with V-57.

  19. Analysis of Heat Removal Capability of PAFS (Passive Auxiliary Feedwater System) in APR (Advanced Power Reactor Plus)

    International Nuclear Information System (INIS)

    As passive safety features for nuclear power plants receive increasing attention, South Korea has designed PAFS (Passive Auxiliary Feedwater System) for APR+ (Advanced Power Reactor Plus). Because the PAFS replaces a conventional active auxiliary feedwater system and plays a role in the ultimate heat sink for decay heat, it is necessary to evaluate the heat removal capability of PAFS under postulated accidents conditions. Therefore, the performance analysis is carried out for two accident cases: Loss of Condenser Vacuum (LOCV) and Feedwater Line Break (FLB) accidents. For the analysis, MARS-KS code is used and MARS-KS model is developed by adding PAFS model to the existing APR1400 model

  20. Analysis of Heat Removal Capability of PAFS (Passive Auxiliary Feedwater System) in APR (Advanced Power Reactor Plus)

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Y. J.; Kang, K. H.; Yun, B. J. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2012-03-15

    As passive safety features for nuclear power plants receive increasing attention, South Korea has designed PAFS (Passive Auxiliary Feedwater System) for APR+ (Advanced Power Reactor Plus). Because the PAFS replaces a conventional active auxiliary feedwater system and plays a role in the ultimate heat sink for decay heat, it is necessary to evaluate the heat removal capability of PAFS under postulated accidents conditions. Therefore, the performance analysis is carried out for two accident cases: Loss of Condenser Vacuum (LOCV) and Feedwater Line Break (FLB) accidents. For the analysis, MARS-KS code is used and MARS-KS model is developed by adding PAFS model to the existing APR1400 model.

  1. 75 FR 3622 - Revisions to Rules Authorizing the Operation of Low Power Auxiliary Stations in the 698-806 MHz...

    Science.gov (United States)

    2010-01-22

    .... The Commission will assist consumers, including those who have previously purchased wireless... Street, SW., Room CY-A257, Washington, DC 20554. It also may be purchased from the Commission's... option, notify any entity operating low power auxiliary stations of its intention to initiate...

  2. 75 FR 34347 - Airworthiness Directives; Honeywell International Inc. Auxiliary Power Unit Models GTCP36-150(R...

    Science.gov (United States)

    2010-06-17

    ... published the proposed AD in the Federal Register on December 23, 2009 (74 FR 68196). That action proposed... Policies and Procedures (44 FR 11034, February 26, 1979); and (3) Will not have a significant economic...) for Honeywell International Inc. auxiliary power unit (APU) models GTCP36- 150(R) and...

  3. Safety analysis and justification for modification of auxiliary feed-water system in Daya Bay Nuclear Power Plant

    International Nuclear Information System (INIS)

    The major feed-water line break accident is re-analyzed, which is based on Guangdong Daya Bay nuclear power station final safety analysis report, to justify the impacts of the decreasing of auxiliary feed-water flow rate on the safety margin in Daya Bay. The results showed that the accident analysis can meet the demands of acceptance criteria with the auxiliary feed-water flowrate decreasing from 45 m3/h to 41.8 m3/h, and enough safety margin is still retained

  4. Auxiliary power unit noise of Boeing B737 and B747 aircraft

    Science.gov (United States)

    Kwan, Jimmy S. W.; Yang, S. J. Eric

    Most modern civil aircraft have an Auxiliary Power Unit (APU) which provides compressed air for engine starting and the air-conditioning system on ground and electrical power for aircraft use both on-ground and in-fligth. It is basically a gas turbine engine and it consists of a compressor section, a turbine section, and an accessory drive section. For Boeing B737 and B747 aircraft, the APU is located inside a compartment in the tail section of the aircraft and is completely enclosed by a sound-reduction fire-proof titanium shroud. APU noise is one of the major noise sources at many airports and is extremely important for a densely populated city such as Hong Kong. The noise from APU can affect many people, including ground crew aircraft maintenance staff, and people living in the vicinity of the airport. However, there is very little information available in the literature about APU noise. This paper describes the noise measurement method and presents the measurement results for APUs of one B747 and two B737 aircraft under both 'loaded' and 'no-load' conditions.

  5. Optimization of Fuel Consumption and Emissions for Auxiliary Power Unit Based on Multi-Objective Optimization Model

    OpenAIRE

    Yongpeng Shen; Zhendong He; Dongqi Liu; Binjie Xu

    2016-01-01

    Auxiliary power units (APUs) are widely used for electric power generation in various types of electric vehicles, improvements in fuel economy and emissions of these vehicles directly depend on the operating point of the APUs. In order to balance the conflicting goals of fuel consumption and emissions reduction in the process of operating point choice, the APU operating point optimization problem is formulated as a constrained multi-objective optimization problem (CMOP) firstly. The four comp...

  6. Novel high power impulse magnetron sputtering enhanced by an auxiliary electrical field

    Science.gov (United States)

    Li, Chunwei; Tian, Xiubo

    2016-08-01

    The high power impulse magnetron sputtering (HIPIMS) technique is a novel highly ionized physical vapor deposition method with a high application potential. However, the electron utilization efficiency during sputtering is rather low and the metal particle ionization rate needs to be considerably improved to allow for a large-scale industrial application. Therefore, we enhanced the HIPIMS technique by simultaneously applying an electric field (EF-HIPIMS). The effect of the electric field on the discharge process was studied using a current sensor and an optical emission spectrometer. Furthermore, the spatial distribution of the electric potential and electric field during the EF-HIPIMS process was simulated using the ANSYS software. The results indicate that a higher electron utilization efficiency and a higher particle ionization rate could be achieved. The auxiliary anode obviously changed the distribution of the electric potential and the electric field in the discharge region, which increased the plasma density and enhanced the degree of ionization of the vanadium and argon gas. Vanadium films were deposited to further compare both techniques, and the morphology of the prepared films was investigated by scanning electron microscopy. The films showed a smaller crystal grain size and a denser growth structure when the electric field was applied during the discharge process.

  7. Novel high power impulse magnetron sputtering enhanced by an auxiliary electrical field.

    Science.gov (United States)

    Li, Chunwei; Tian, Xiubo

    2016-08-01

    The high power impulse magnetron sputtering (HIPIMS) technique is a novel highly ionized physical vapor deposition method with a high application potential. However, the electron utilization efficiency during sputtering is rather low and the metal particle ionization rate needs to be considerably improved to allow for a large-scale industrial application. Therefore, we enhanced the HIPIMS technique by simultaneously applying an electric field (EF-HIPIMS). The effect of the electric field on the discharge process was studied using a current sensor and an optical emission spectrometer. Furthermore, the spatial distribution of the electric potential and electric field during the EF-HIPIMS process was simulated using the ANSYS software. The results indicate that a higher electron utilization efficiency and a higher particle ionization rate could be achieved. The auxiliary anode obviously changed the distribution of the electric potential and the electric field in the discharge region, which increased the plasma density and enhanced the degree of ionization of the vanadium and argon gas. Vanadium films were deposited to further compare both techniques, and the morphology of the prepared films was investigated by scanning electron microscopy. The films showed a smaller crystal grain size and a denser growth structure when the electric field was applied during the discharge process. PMID:27587123

  8. A CAE package for design of auxiliary buildings in nuclear power plants

    International Nuclear Information System (INIS)

    Nuclear power plants have a large number of auxiliary buildings housing various services and control systems in addition to the main reactor building. These are usually of the framed construction of two or three floors falling under seismic class I or II. Class I structures have to be qualified for seismic forces of intensity as given by SSE (safe shutdown earthquake) for three orthogonal components acting simultaneously while class II structures need to be qualified for seismic forces of intensity as given by OBE (operating basis earthquake) for two component motion-one horizontal and one vertical acting simultaneously. The seismic analysis of these buildings is carried out using the BLOCK model. For the analysis of three component motion, USNRC R.G. 1.92 permits time history method of analysis and timewise combination of responses of the three components in the proper phases. However, such a method of analysis is uneconomical for the buildings in question, more so when the layouts of such buildings during the planning phases undergo quite a few revisions necessitating reanalysis. As such, the response spectrum method of analysis is adopted for each directional component and the responses to the three component excitation are combined by adopting the SRSS criteria

  9. Development of 8 MW Power Supply Based on Pulse Step Modulation Technique for Auxiliary Heating System on HL-2A

    Science.gov (United States)

    Xu, Weidong; Xuan, Weimin; Yao, Lieying; Wang, Yingqiao

    2012-03-01

    The high voltage power supply (HVPS) based on pulse step modulation (PSM) has already been developed for the auxiliary heating system on HL-2A. This power supply consists of many switch power supplies, and its output voltage can be obtained by modulating their delay time and pulse widths. The PSM topology and control principle are presented in this paper. The simple algorithms for the control system are explained clearly. The switch power supply (SPS) module has been built and the test results show it can meet the requirements of the auxiliary heating system. Now, 112 SPS modules and the whole system have already been developed. Its maximum output is about 72 kV/93 A. The protection time is less than 5 μs. The different outputs of this power supply are used for the electron cyclotron resonant heating (ECRH) system with different duty ratios. The experimental results of the entire system are presented. The results indicate that the whole system can meet the requirements of the auxiliary heating system on HL-2A.

  10. Fuel handling machine and auxiliary systems for a fuel handling cell

    International Nuclear Information System (INIS)

    This working report is an update for as well as a supplement to an earlier fuel handling machine design (Kukkola and Roennqvist 2006). A focus in the earlier design proposal was primarily on the selection of a mechanical structure and operating principle for the fuel handling machine. This report introduces not only a fuel handling machine design but also auxiliary fuel handling cell equipment and its operation. An objective of the design work was to verify the operating principles of and space allocations for fuel handling cell equipment. The fuel handling machine is a remote controlled apparatus capable of handling intensely radiating fuel assemblies in the fuel handling cell of an encapsulation plant. The fuel handling cell is air tight space radiation-shielded with massive concrete walls. The fuel handling machine is based on a bridge crane capable of traveling in the handling cell along wall tracks. The bridge crane has its carriage provided with a carousel type turntable having mounted thereon both fixed and telescopic masts. The fixed mast has a gripper movable on linear guides for the transfer of fuel assemblies. The telescopic mast has a manipulator arm capable of maneuvering equipment present in the fuel handling cell, as well as conducting necessary maintenance and cleaning operations or rectifying possible fault conditions. The auxiliary fuel handling cell systems consist of several subsystems. The subsystems include a service manipulator, a tool carrier for manipulators, a material hatch, assisting winches, a vacuum cleaner, as well as a hose reel. With the exception of the vacuum cleaner, the devices included in the fuel handling cell's auxiliary system are only used when the actual encapsulation process is not ongoing. The malfunctions of mechanisms or actuators responsible for the motion actions of a fuel handling machine preclude in a worst case scenario the bringing of the fuel handling cell and related systems to a condition appropriate for

  11. Seismic Back Calculation of an Auxiliary Building of the Nuclear Power Plant Muehleberg, Switzerland

    International Nuclear Information System (INIS)

    The auxiliary storage building of the Muehleberg nuclear power plant houses all the equipment for checking, intermediate storage and the treatment of all solid, liquid and gas products deriving from the operation of the plant, which may have been exposed to radiation. Due to the systems installed in the building it has to resist an earthquake of intensity level OBE (Operating Basis Earthquake). A corresponding verification was not carried out when the plant was constructed. To fulfil the requirements of the regulatory commission (HSK) the seismic safety of the storage facility had to undergo a detailed investigation. The following studies were made within the framework of this investigation: preparation of a concept; specifying the most important aspects and boundary conditions; calculation of the frequency-dependent impedance function of the ground with 3-D soil and foundation computational models for different depths of embedment; execution of the soil-structure interaction analysis with 3-D lumped mass models; preparation of a refined 3-D finite element model of the structure; verification of the model by checking the masses; execution of the modal analysis to determine the dynamic behaviour; execution of the static analysis with the operational loads; execution of the seismic analysis using the response spectrum method; superposition of stresses from the static and seismic analyses; execution of the geotechnical stability analyses; execution of the local stress and bearing capacity verifications; determination of the floor response spectra. The results are in agreement with observations from real earthquakes, which is a good indicator of the reliability of the methods employed and the computational models

  12. Characteristics of Ne-Xe microplasma in unit discharge cell of plasma display panel equipped with counter sustain electrodes and auxiliary electrodes

    International Nuclear Information System (INIS)

    The performance of a new structure plasma display panel (PDP) cell with counter sustain electrodes was diagnosed by optical emission and laser absorption spectroscopic measurements of the spatiotemporal behaviours of the microplasma. Two different types of panels were prepared: one with sustain electrodes only and the other with additional data and auxiliary electrodes on the rear and front plates. By using cells of the former type, the basic performance was measured as the dependences on the Xe concentration in Ne, the total pressure and the applied sustain voltage. It was seen that a higher Xe concentration was advantageous for the luminous efficiency although the required minimum sustain voltage became larger. By using the latter type of cell, the effects of driving schemes were investigated by varying the applied potentials onto the auxiliary and data electrodes. It was found that the role of the auxiliary electrode is remarkable; the discharge expands largely in the cell when the voltage and the width of the pulses applied to the auxiliary electrode are optimized to be 200 V and 0.3 μs, respectively, while the data electrode is grounded. The production efficiency of Xe atoms in the metastable (1s5) and resonance (1s4) states was derived from the measured absolute densities normalized by the input power per cell and the decay rates of those densities. The vacuum ultraviolet emission efficiency estimated from the results was compared between the tested conditions, and a noticeable improvement was recognized in the optimized condition, about 40% larger than a conventional driving condition without additional pulses. It was also seen that this cell structure is potentially superior in luminous efficiency to the conventional coplanar structure currently used in commercial PDPs

  13. Fuel Cell and Battery Powered Forklifts

    DEFF Research Database (Denmark)

    Zhang, Zhe; Mortensen, Henrik H.; Jensen, Jes Vestervang;

    2013-01-01

    propulsion similar to batteries. In this paper, the performance of a forklift powered by PEM fuel cells and lead acid batteries as auxiliary energy source is introduced and investigated. In this electromechanical propulsion system with hybrid energy/power sources, fuel cells will deliver average power......A hydrogen-powered materials handling vehicle with a fuel cell combines the advantages of diesel/LPG and battery powered vehicles. Hydrogen provides the same consistent power and fast refueling capability as diesel and LPG, whilst fuel cells provide energy efficient and zero emission Electric......, whilst batteries will handle all the load dynamics, such as acceleration, lifting, climbing and so on. The electrical part of the whole propulsion system for forklift has been investigated in details. The energy management strategy is explained and verified through simulation. Finally, experimental...

  14. Experimental simulation of a light aircraft crash on to a nuclear power plant auxiliary building roof

    International Nuclear Information System (INIS)

    The experiments described were conducted at a reduced scale with geometric dimensions of prototype structures of one-fifth full size. The target was based on the auxiliary buildings for the proposed Sizewell PWR. Descriptions of the simulated aircraft model and the test panels are given, together with the instrumentation. Details are given of the test programme and the results are summarized and discussed. Comparison is made of the model aircraft tests with an equivalent hard missile impact. (U.K.)

  15. Preliminary safety analysis report for the Auxiliary Hot Cell Facility, Sandia National Laboratories, Albuquerque, New Mexico

    Energy Technology Data Exchange (ETDEWEB)

    OSCAR,DEBBY S.; WALKER,SHARON ANN; HUNTER,REGINA LEE; WALKER,CHERYL A.

    1999-12-01

    The Auxiliary Hot Cell Facility (AHCF) at Sandia National Laboratories, New Mexico (SNL/NM) will be a Hazard Category 3 nuclear facility used to characterize, treat, and repackage radioactive and mixed material and waste for reuse, recycling, or ultimate disposal. A significant upgrade to a previous facility, the Temporary Hot Cell, will be implemented to perform this mission. The following major features will be added: a permanent shield wall; eight floor silos; new roof portals in the hot-cell roof; an upgraded ventilation system; and upgraded hot-cell jib crane; and video cameras to record operations and facilitate remote-handled operations. No safety-class systems, structures, and components will be present in the AHCF. There will be five safety-significant SSCs: hot cell structure, permanent shield wall, shield plugs, ventilation system, and HEPA filters. The type and quantity of radionuclides that could be located in the AHCF are defined primarily by SNL/NM's legacy materials, which include radioactive, transuranic, and mixed waste. The risk to the public or the environment presented by the AHCF is minor due to the inventory limitations of the Hazard Category 3 classification. Potential doses at the exclusion boundary are well below the evaluation guidelines of 25 rem. Potential for worker exposure is limited by the passive design features incorporated in the AHCF and by SNL's radiation protection program. There is no potential for exposure of the public to chemical hazards above the Emergency Response Protection Guidelines Level 2.

  16. Preliminary safety analysis report for the Auxiliary Hot Cell Facility, Sandia National Laboratories, Albuquerque, New Mexico

    International Nuclear Information System (INIS)

    The Auxiliary Hot Cell Facility (AHCF) at Sandia National Laboratories, New Mexico (SNL/NM) will be a Hazard Category 3 nuclear facility used to characterize, treat, and repackage radioactive and mixed material and waste for reuse, recycling, or ultimate disposal. A significant upgrade to a previous facility, the Temporary Hot Cell, will be implemented to perform this mission. The following major features will be added: a permanent shield wall; eight floor silos; new roof portals in the hot-cell roof; an upgraded ventilation system; and upgraded hot-cell jib crane; and video cameras to record operations and facilitate remote-handled operations. No safety-class systems, structures, and components will be present in the AHCF. There will be five safety-significant SSCs: hot cell structure, permanent shield wall, shield plugs, ventilation system, and HEPA filters. The type and quantity of radionuclides that could be located in the AHCF are defined primarily by SNL/NM's legacy materials, which include radioactive, transuranic, and mixed waste. The risk to the public or the environment presented by the AHCF is minor due to the inventory limitations of the Hazard Category 3 classification. Potential doses at the exclusion boundary are well below the evaluation guidelines of 25 rem. Potential for worker exposure is limited by the passive design features incorporated in the AHCF and by SNL's radiation protection program. There is no potential for exposure of the public to chemical hazards above the Emergency Response Protection Guidelines Level 2

  17. Holistic Modeling, Design & Analysis of Integrated Stirling and Auxiliary Clean Energy Systems for Combined Heat and Power Applications

    Science.gov (United States)

    Nayak, Amrit Om

    The research revolves around the development of a model to design and analyze Stirling systems. Lack of a standard approach to study Stirling systems and difficulty in generalizing existing approaches pose stiff challenges. A stable mathematical model (integrated second order adiabatic and dynamic model) is devised and validated for general use. The research attempts to design compact combined heat and power (CHP) system to run on multiple biomass fuels and solar energy. Analysis is also carried out regarding the design of suitable auxiliary systems like thermal energy storage system, biomass moisture removal system and Fresnel solar collector for the CHP Stirling system.

  18. Design of condensation heat exchanger for the PAFS (Passive Auxiliary Feedwater System) of APR+ (Advanced Power Reactor Plus)

    International Nuclear Information System (INIS)

    Highlights: ► Condensation heat exchanger for the PAFS (Passive Auxiliary Feedwater System) was designed. ► The requirement of the heat removal rate and the prevention of water hammer phenomena were considered. ► The proposed design of the heat exchanger satisfied the requirement of the passive heat removal system. - Abstract: The APR+ (Advanced Power Reactor Plus), a next generation nuclear power plant in Korea, has adopted the PAFS (Passive Auxiliary Feedwater System) on the secondary system of the steam generator (SG) as an advanced safety feature. It is intended to replace the conventional auxiliary feedwater system, which consists of active components for the SG in a passive way. It removes decay heat from the reactor core by cooling down the secondary system of the SG using a condensation heat exchanger installed in the PCCT (Passive Condensation Cooling Tank). The objective of this study is to design a condensation heat exchanger for the PAFS and to evaluate the cooling performance for the proposed design using the thermal hydraulic system analysis code, MARS (Multi-dimensional Analysis for Reactor Safety). Requirements such as the heat removal capacity and the prevention of water hammer were preferentially considered to determine the design parameters of the heat exchanger tube. The MARS code analysis result showed that the proposed design of the PAFS heat exchanger is able to cool down the required amount of decay heat. The distribution of a liquid volume fraction and flow regime predicted by the MARS code shows that the proposed design of the heat exchanger excludes the water hammer inside the tube. Estimation of a two-phase flow pressure drop indicates that the pressure drop inside the tube is negligible compared to the total pressure drop in the PAFS. From the MARS code analysis, it is concluded that the proposed design of the condensation heat exchanger in the PAFS satisfies the overall criteria for the performance of the passive heat removal

  19. Aging and service wear of auxiliary feedwater pumps for PWR nuclear power plants

    International Nuclear Information System (INIS)

    This paper describes investigations on auxiliary feedwater pumps being done under the Nuclear Plant Aging Research (NPAR) Program. Objectives of these studies are: to identify and evaluate practical, cost-effective methods for detecting, monitoring, and assessing the severity of time-dependent degradation (aging and service wear); recommend inspection and maintenance practices; establish acceptance criteria; and help facilitate use of the results. Emphasis is given to identifying and assessing methods for detecting failure in the incipient stage and to developing degradation trends to allow timely maintenance, repair or replacement actions. 3 refs

  20. Operation auxiliary system (SAO)

    International Nuclear Information System (INIS)

    This work presents an auxiliary system for nuclear power plants operation (SAO). The development purpose consisted in a computing supervision system to be installed at different sites of a reactor, mainly in the control room. The inclusion of this system to a nuclear power plant minimizes the possibility of human error for the facility operation. (Author)

  1. Auxiliary feedwater system risk-based inspection guide for the Point Beach nuclear power plant

    International Nuclear Information System (INIS)

    In a study sponsored by the US Nuclear Regulatory Commission (NRC), Pacific Northwest Laboratory has developed and applied a methodology for deriving plant-specific risk-based inspection guidance for the auxiliary feedwater (AFW) system at pressurized water reactors that have not undergone probabilistic risk assessment (PRA). This methodology uses existing PRA results and plant operating experience information. Existing PRA-based inspection guidance information recently developed for the NRC for various plants was used to identify generic component failure modes. This information was then combined with plant-specific and industry-wide component information and failure data to identify failure modes and failure mechanisms for the AFW system at the selected plants. Point Beach was selected as one of a series of plants for study. The product of this effort is a prioritized listing of AFW failures which have occurred at the plant and at other PWRS. This listing is intended for use by NRC inspectors in the preparation of inspection plans addressing AFW risk-important components at the Point Beach plant

  2. Auxiliary feedwater system risk-based inspection guide for the Virgil C. Summer Nuclear Power Plant

    International Nuclear Information System (INIS)

    In a study sponsored by the US Nuclear Regulatory Commission (NRC), Pacific Northwest Laboratory has developed and applied a methodology for deriving plant-specific risk-based inspection guidance for the emergency/auxiliary feedwater (EFW/AFW) system at press water reactors that have not undergone probabilistic risk assessment (PRA). This methodology uses costing PRA results and plant operating experience information. Existing PRA-based inspection guidance information recently developed for the NRC for various plants was used to identify genetic component failure modes. This information was then combined with plant-specific and industry-wide component information and failure data to identify failure modes and failure mechanisms for the AFW system at the selected plants. Virgil C. Summer plant was selected as one m a series of plants for study. The product of this effort is a priority listing of AFW failures which have occurred at the plant and at other PWRS. This listing is intended for use by NRC inspectors in the preparation of inspection plans addressing AFW risk-important components at Virgil C. Summer plant

  3. Auxiliary systems

    International Nuclear Information System (INIS)

    For a undisturbed reactor operation, the various Auxiliary and Ancillary Systems must function perfectly with the Reactor Coolant System together. While the Auxiliary Systems are directly connected to the Reactor Coolant System and therefore have contact with the Reactor Coolant, the Ancillary Systems perform tasks which do not directly influence reactor operation and in part are necessary exclusively for environment protection. The design criteria of the individual systems are a result of these tasks, especially in relation to availability, operational readiness and probability of failure. (orig.)

  4. Investigations in the modelling and control of a medium voltage hybrid inverter system that uses a low voltage /low power rated auxiliary current source inverter

    OpenAIRE

    Papadopoulos, Savvas; Rashed, Mohamed; Klumpner, Christian; Wheeler, Patrick

    2016-01-01

    Hybrid converters consist of a main inverter processing the bulk of the power with poor waveform performance and a fast and versatile auxiliary inverter to correct the distortion. In this paper, the main converter is a medium voltage NPC inverter and the auxiliary inverter is a low-voltage and low-current rated current source inverter (CSI), with series capacitor being used to minimize the CSI voltage stress. The result is a high output current quality which is obtained with a very low switch...

  5. Auxiliary building structures

    International Nuclear Information System (INIS)

    Five types of auxiliary structures are described such as were used during the construction of the Dukovany nuclear power plant, namely a portable staircase tower, a stable staircase tower, mobile tower scaffolding, mobile scaffolding on a crane track and a scaffold cradle. Basic technical data for all types of scaffolding are given. (Pu)

  6. CAREM-25. Auxiliary systems

    International Nuclear Information System (INIS)

    CAREM is an innovative PWR reactor whose prototype will be of small power generation capacity (100 M Wt, about 25 M We). CAREM design is based on light water integrated reactor with slightly enriched uranium. In this work, a summary of the functions and most relevant design characteristics of main auxiliary systems associated to the chain of heat removal and physicochemical - radiological treatment of the cooling fluids of the CAREM-25 prototype is presented. Even though these auxiliary systems of the reactor are not safety system, they fulfill functions related with the nuclear safety at different operative modes of the reactor. (author)

  7. CAREM-25. Auxiliary systems

    International Nuclear Information System (INIS)

    CAREM is an innovative PWR reactor whose prototype will be of small power generation capacity (100MWt, about 25MWe).CAREM design is based on light water integrated reactor with slightly enriched uranium.In this work, a summary of the functions and most relevant design characteristics of main auxiliary systems associated to the chain of heat removal and physicochemical - radiological treatment of the cooling fluids of the CAREM-25 prototype is presented.Even though these auxiliary systems of the reactor are not safety system, they fulfill functions related with the nuclear safety at different operative modes of the reactor

  8. Sensitivity of Power Station Auxiliary Network to the Possibility of Ferroresonance Occurrence

    Directory of Open Access Journals (Sweden)

    Józef Wiśniewski

    2014-12-01

    Full Text Available Implementation of the new class of 1000 MW power units to a power system creates new problems associated with the operation of its individual components and circuits. One such issue is the phenomenon of ferroresonance in the internal load network. This is not a new problem but it requires examination due to the higher level of supply voltage (10 kV. This paper examines the possibility of ferroresonance occurrence and its character depending on the extent of the network, voltage transformers’ load, the effect of grounding resistors in the star point of the power transformer and the presence of varistor surge arresters. The results are presented in the form of ferroresonance maps. They allow assessing the impact of various parameters on the phenomenon, explaining the reasons for possible failure and properly programming the network conditions in order to avoid the risk of ferroresonance.

  9. Optimization of Fuel Consumption and Emissions for Auxiliary Power Unit Based on Multi-Objective Optimization Model

    Directory of Open Access Journals (Sweden)

    Yongpeng Shen

    2016-02-01

    Full Text Available Auxiliary power units (APUs are widely used for electric power generation in various types of electric vehicles, improvements in fuel economy and emissions of these vehicles directly depend on the operating point of the APUs. In order to balance the conflicting goals of fuel consumption and emissions reduction in the process of operating point choice, the APU operating point optimization problem is formulated as a constrained multi-objective optimization problem (CMOP firstly. The four competing objectives of this CMOP are fuel-electricity conversion cost, hydrocarbon (HC emissions, carbon monoxide (CO emissions and nitric oxide (NO x emissions. Then, the multi-objective particle swarm optimization (MOPSO algorithm and weighted metric decision making method are employed to solve the APU operating point multi-objective optimization model. Finally, bench experiments under New European driving cycle (NEDC, Federal test procedure (FTP and high way fuel economy test (HWFET driving cycles show that, compared with the results of the traditional fuel consumption single-objective optimization approach, the proposed multi-objective optimization approach shows significant improvements in emissions performance, at the expense of a slight drop in fuel efficiency.

  10. Mechanical (turbines and auxiliary equipment)

    CERN Document Server

    Sherry, A; Cruddace, AE

    2013-01-01

    Modern Power Station Practice, Volume 3: Mechanical (Turbines and Auxiliary Equipment) focuses on the development of turbines and auxiliary equipment used in power stations in Great Britain. Topics covered include thermodynamics and steam turbine theory; turbine auxiliary systems such as lubrication systems, feed water heating systems, and the condenser and cooling water plants. Miscellaneous station services, and pipework in power plants are also described. This book is comprised of five chapters and begins with an overview of thermodynamics and steam turbine theory, paying particular attenti

  11. Energy Efficiency of Thermal Power Station Auxiliary Power Consumption and Cost Savings in Carbon Footprint in India

    OpenAIRE

    K. Thirumavalavan; Mathi Ramalingam; Jayalalitha Subbaiahan

    2014-01-01

    This study discusses about the energy conservation and carbon credits in Thermal Power Stations in India. Indian power scenario, accounts for 66.4% (1,36,436 MW) of Thermal Power Generation. The Thermal Power Stations have the problem of consuming 8.5% of power it produces. Also it has the drawback of emission factors which leaves the carbon footprint, which has to be controlled as per the Clean Development Mechanism (CDM). The United Nations Framework watches ...

  12. Design Considerations for a PEM Fuel Cell Powered Truck APU

    OpenAIRE

    Grupp, David J; Forrest, Matthew E.; Mader, Pippin G.; Brodrick, Christie-Joy; Miller, Marshall; Dwyer, Harry A.

    2004-01-01

    In recent years interest has been growing in using fuel cell powered auxiliary power units (APUs) to reduce idling in line-haul trucks. Demonstrations of this technology have been constructed at universities and within industry, each with its own advantages and disadvantages. Invariably, in every design, tradeoffs need to be made and this has resulted in a multitude of different APU solutions that address different aspects of the problem. This paper reviews some of the recent work re...

  13. Design Considerations for a PEM Fuel Cell Powered Truck APU

    OpenAIRE

    Grupp, David J; Forrest, Matthew E.; Mader, Pippin G.; Brodrick, Christie-Joy; Miller, Marshall; Dwyer, Harry A.

    2004-01-01

    In recent years interest has been growing in using fuel cell powered auxiliary power units (APUs) to reduce idling in line-haul trucks. Demonstrations of this technology have been constructed at universities and within industry, each with its own advantages and disadvantages. Invariably, in every design, tradeoffs need to be made and this has resulted in a multitude of different APU solutions that address different aspects of the problem. This paper reviews some of the recent work related to ...

  14. Lessons learned from full-scale vibration tests on nuclear power plant auxiliary structure in Switzerland

    International Nuclear Information System (INIS)

    The Beznau Nuclear Power Plant is located in northern Switzerland. The plant is owned and operated by the Nordostschweizerische Kraftwerke AG (NOK) in Baden, Switzerland. It is a twin unit plant (2 x 350 MWe) which was designed in the early 1960's and placed into commercial operation between 1969 and 1971. In connection with a major backfit project, which will improve the safety of the plant against external events, the free-standing boric water tanks had to be relocated and were replaced by two boric water tanks in a new building (the so called BOTA-building). It enabled to plan and perform full scale vibration tests.The scope of experimental investigation was to determine the eigenfrequencies and damping values for fundamental soil-structure interaction. The vibration tests allowed identification of the important modes of the soil-structure system in the range 3 to 15 Hz. The excitation was strung enough to generate accelerations in the structure comparable to those of a small earthquake. From the comparisons of computed and measured results it is concluded that the rocking frequency can be reasonably well predicted by either Finite Element or Lumped Parameter models with springs simulating the soil-foundation stiffness, provided in the case of the latter the embedment is taken into account. The prediction of the amplitude of structural response appears to be more difficult, as shown by the differences in the mode shapes. In the frequency range 8 to 10 Hz the agreement between computed and test results was less satisfactory. The actual structural behaviour turned out to be more complex than expected and needs further investigation with the aid of more refined models for the soil-structure system

  15. Performance Based Logistics (PBL) for the FA-18/S-3/P-3/C-2 auxiliary power unit (APU) at Honeywell: an applied analysis

    OpenAIRE

    Landreth, Clifford J.; Corporon, Laura L.; Wilhelm, Richard H.

    2005-01-01

    The purpose of this MBA project is to evaluate and assess the metrics, incentives and other terms and conditions of the Performance Based Logistics (PBL) contract between Naval Aviation Inventory Control Point (NAVICP) and Honeywell in support of FA-18/S-3/P-3/C-2 Auxiliary Power Unit (APU) to determine if the contractual terms and conditions established are effective in facilitating and encouraging the full potential of PBL savings and improved performance. PBL is an acquisition reform initi...

  16. Determination of the emissions from an aircraft auxiliary power unit (APU) during the Alternative Aviation Fuel Experiment (AAFEX).

    Science.gov (United States)

    Kinsey, John S; Timko, Michael T; Herndon, Scott C; Wood, Ezra C; Yu, Zhenhong; Miake-Lye, Richard C; Lobo, Prem; Whitefield, Philip; Hagen, Donald; Wey, Changlie; Anderson, Bruce E; Beyersdorf, Andreas J; Hudgins, Charles H; Thornhill, K Lee; Winstead, Edward; Howard, Robert; Bulzan, Dan I; Tacina, Kathleen B; Knighton, W Berk

    2012-04-01

    The emissions from a Garrett-AiResearch (now Honeywell) Model GTCP85-98CK auxiliary power unit (APU) were determined as part of the National Aeronautics and Space Administration's (NASA's) Alternative Aviation Fuel Experiment (AAFEX) using both JP-8 and a coal-derived Fischer Tropsch fuel (FT-2). Measurements were conducted by multiple research organizations for sulfur dioxide (SO2, total hydrocarbons (THC), carbon monoxide (CO), carbon dioxide (CO2), nitrogen oxides (NOx), speciated gas-phase emissions, particulate matter (PM) mass and number, black carbon, and speciated PM. In addition, particle size distribution (PSD), number-based geometric mean particle diameter (GMD), and smoke number were also determined from the data collected. The results of the research showed PM mass emission indices (EIs) in the range of 20 to 700 mg/kg fuel and PM number EIs ranging from 0.5 x 10(15) to 5 x 10(15) particles/kg fuel depending on engine load and fuel type. In addition, significant reductions in both the SO2 and PM EIs were observed for the use of the FT fuel. These reductions were on the order of approximately 90% for SO2 and particle mass EIs and approximately 60% for the particle number EI, with similar decreases observed for black carbon. Also, the size of the particles generated by JP-8 combustion are noticeably larger than those emitted by the APU burning the FT fuel with the geometric mean diameters ranging from 20 to 50 nm depending on engine load and fuel type. Finally, both particle-bound sulfate and organics were reduced during FT-2 combustion. The PM sulfate was reduced by nearly 100% due to lack of sulfur in the fuel, with the PM organics reduced by a factor of approximately 5 as compared with JP-8. PMID:22616284

  17. Determination of power and power descriptions at walking with auxiliary facilities of pushing (by sticks away from lower support

    Directory of Open Access Journals (Sweden)

    Adashevskiy V.M.

    2012-04-01

    Full Text Available A purpose of work is a design of motions in Nordic walking, and analysis of power and power descriptions of motion. The basic aspects of walking with sticks and their influence on quality of life of people of different age are considered. Directions of the use of physical exercises for the people of senior age are selected. Possibilities of the use of walking in the physical rehabilitation of patients and people with a hyposthenic health is shown. It is set that, walking extend the use of models of Nordic possibility of leadthrough of researches and theoretical ground for more deep study of features of such type of movements. It is marked that the model of motion is expedient to utillize in combination with cinegram walking and by the indexes of dynamometry. It is recommended at lowering to observe the rules of technique of motion and safety.

  18. Optimization of relay protection for a auxiliary power system%厂用电系统继电保护优化

    Institute of Scientific and Technical Information of China (English)

    李子峰

    2015-01-01

    基于对厂用电系统继电保护中存在的配置不完整、后备保护动作时间过长等问题的分析,提出了配置6 kV 母线专用主保护、在低压厂用电系统变压器高压侧增加限时电流速断保护装置、优化后备保护之间配合的方案,并以此对厂用电系统的继电保护配置进行了优化,以600 MW机组为例,进行了保护整定计算,结果表明,优化后的厂用电系统继电保护配置完整,保护范围合理,后备保护动作时间显著缩短。从而,提高了厂用电系统继电保护动作的快速性和厂用电系统运行安全性。%On the basis of analysis on some questions of relay protection in auxiliary power systems,like the imperfection in configuration and the actuation time is too long,a scheme was proposed for relay protection design,such as configuring a specialized main protection for 6 kV busbar,adding a time limited current fast-trip protection on the high-voltage side of low-voltage transformers in auxiliary power system,optimizing the cooperation of reserve protections and then designing the configuration of relay protection in auxiliary power system according to the optimizing rule.Taking a 600 MW unit as the example,settings calculation was carried out.The results proved that the configuration of relay protection in auxiliary power system is integrated perfectly due to the optimization,the coverage of protection is reasonable and the actuation time of reserve protection has been remarkably shortened.Thus,the actuation speed and security of the auxiliary power system are promoted.

  19. Infrared power cells for satellite power conversion

    Science.gov (United States)

    Summers, Christopher J.

    1991-01-01

    An analytical investigation is performed to assess the feasibility of long-wavelength power converters for the direct conversion of IR radiation onto electrical power. Because theses devices need to operate between 5 and 30 um the only material system possible for this application is the HgCdTe system which is currently being developed for IR detectors. Thus solar cell and IR detector theories and technologies are combined. The following subject areas are covered: electronic and optical properties of HgCdTe alloys; optimum device geometry; junction theory; model calculation for homojunction power cell efficiency; and calculation for HgCdTe power cell and power beaming.

  20. Vertical vibration test results of auxiliary building of the No. 1 Genkai nuclear power plant utilizing explosion test of excavating base rocks of the No. 2 plant

    International Nuclear Information System (INIS)

    The vertical vibration behavior of the auxiliary building of the No. 1 Genkai nuclear power plant was examined, utilizing the explosion test of excavation for the No. 2 plant, about 60 m apart from the auxiliary building. The explosive from 2.25 to 33.8 kg was used for simultaneous explosion and 13.4 to 47.4 kg for stepwise explosions, and the tests of ten explosions were conducted, divided into three cases. Concerning the test results, the wave forms were obtained at many points in the auxiliaty building within about one second after explosion. The first mode natural frequency was about 10 - 25 Hz, and the damping coefficient was 1 - 10%. The elastic behavior and about two times amplifying response at the top as compared to the basement were observed in the vibration of the building. The local frequency in the vertical vibration was different according to the individual points in the building, as the building has large area and several floors with complicated structures. The running spectra, Fourier spectra and power spectra were obtained experimentally. On the other hand, the numerical analysis was conducted using the particle system model, and compared to the experimental results, and the calculated values were about 1.5 - 2.0 times as large as the experimental values in the maximum responses. As for the experiment, the horizontal vibration behavior was also measured, which showed a little different vibrating characteristic curves. This experiment was effective to get the qualitative knowledge for the vertical vibration behavior of the auxiliary building in a nuclear power plant. (Nakai, Y.)

  1. Optimizationin Operational Analysis of Auxiliary Steam System in Thermal Power Plant%火力发电厂辅汽系统优化运行分析

    Institute of Scientific and Technical Information of China (English)

    王乃军; 白秀春; 王俊俊

    2015-01-01

    For choosing different steam source for the auxiliary steam system in Inner Mongolia Daihai Electric Power Generation Co.,Ltd., carry on the quantitative analysis to the influence of the unit efficiency, the result is the most economical when choosing No.4 extraction steam of second unit supplying, while slightly economical as using second unit cold reheater as first unit. According to the results of the analysis, it provides a theoretical basis and guidance for selecting the source of auxiliary steam in power plants, so as to achieve the purpose of saving energy and reducing consumption, improve the operation efficiency. At the same time, based on the actual operating mode, unit start-up and shutdown, accident conditions, combined with different seasons and temperature, auxiliary steam consumption, it proposes operation precautions.%对内蒙古岱海发电有限责任公司辅助蒸汽系统选择不同供汽汽源时,机组运行经济性受到的影响进行了定量分析,认为由二期机组四段抽汽供汽经济性最优,由二期机组冷段再热蒸汽供汽的经济性略优于由一期机组冷段再热蒸汽供汽。并结合机组实际运行方式、机组启停方式及机组发生事故时的运行情况等,根据不同季节环境温度及各辅汽用户用汽量情况,提出辅汽系统优化运行注意事项。

  2. 辅助动力装置建模及数值仿真%Model and numerical simulation of auxiliary power unit

    Institute of Scientific and Technical Information of China (English)

    常博博; 苏三买; 刘铁庚; 刘美凤

    2011-01-01

    In order to supporting auxiliary power unit(APU) design,the widely used APU with load compressor in structure was discussed and modeled.Firstly,the structural characteristics and regulation law are introduced and then how the load compressor works on APU was analyzed.Finally the mathematic model of APU was established based on components.Take a kind of APU as the object for numerical simulation and then compare with the actual test data.The results show that the dynamic simulation error is less than 5%.The mathematic model of APU is suitable for engineering usage.%为辅助APU(auxiliary power unit)的研发,以目前广泛应用的带负载压气机结构APU为研究对象,进行建模分析与研究.首先介绍了APU结构特点与调节规律,然后分析了负载压气机对APU共同工作的影响,最后采用部件法建立了该类型APU数学模型并设计仿真软件.以某型APU为对象,数值仿真与实际试车数据比较,结果表明所采用的建模方法是正确的,计算误差小于5%,所建立的模型能够满足工程需求.

  3. Turbine generator and its auxiliaries

    International Nuclear Information System (INIS)

    The turbine generator and its auxiliary systems in Tarapur Atomic Power Station (TAPS) have been performing well and further their performance and availability has increased due to timely assessment of the problems anticipated in the systems by a close co-ordination among the concerned staff. Continued efforts are on for further improvements. (author)

  4. Modeling, analysis and control of fuel cell hybrid power systems

    Science.gov (United States)

    Suh, Kyung Won

    Transient performance is a key characteristic of fuel cells, that is sometimes more critical than efficiency, due to the importance of accepting unpredictable electric loads. To fulfill the transient requirement in vehicle propulsion and portable fuel cell applications, a fuel cell stack is typically coupled with a battery through a DC/DC converter to form a hybrid power system. Although many power management strategies already exist, they all rely on low level controllers that realize the power split. In this dissertation we design controllers that realize various power split strategies by directly manipulating physical actuators (low level commands). We maintain the causality of the electric dynamics (voltage and current) and investigate how the electric architecture affects the hybridization level and the power management. We first establish the performance limitations associated with a stand-alone and power-autonomous fuel cell system that is not supplemented by an additional energy storage and powers all its auxiliary components by itself. Specifically, we examine the transient performance in fuel cell power delivery as it is limited by the air supplied by a compressor driven by the fuel cell itself. The performance limitations arise from the intrinsic coupling in the fluid and electrical domain between the compressor and the fuel cell stack. Feedforward and feedback control strategies are used to demonstrate these limitations analytically and with simulations. Experimental tests on a small commercial fuel cell auxiliary power unit (APU) confirm the dynamics and the identified limitations. The dynamics associated with the integration of a fuel cell system and a DC/DC converter is then investigated. Decentralized and fully centralized (using linear quadratic techniques) controllers are designed to regulate the power system voltage and to prevent fuel cell oxygen starvation. Regulating these two performance variables is a difficult task and requires a compromise

  5. Study of auxiliary power systemsfor offshore wind turbines : an extended analysis of a diesel gen-setsolution

    OpenAIRE

    Berggren, Joakim

    2013-01-01

    Until today the offshore wind power has grown in a steady pace and many new wind farms are being constructed around the globe. An important factor that is investigated today in the industry are the security of power supply to the equipment needed for controlling the offshore system during emergency situations. When a offshore wind farm is disconnected from the external grid and an emergency case occur the wind turbine generators lose their ability to transfer power and they are forced to be t...

  6. Auxiliary verbs in Dinka

    DEFF Research Database (Denmark)

    Andersen, Torben

    2007-01-01

    Dinka, a Western Nilotic language, has a class of auxiliary verbs which is remarkable in the following four respects: (i) It is unusually large, comprising some 20 members; (ii) it is grammatically homogeneous in terms of both morphology and syntax; (iii) most of the auxiliary verbs correspond to...

  7. The Subsection Control Strategy Used for the Auxiliary Power Unit Electrical Start%应用于APU电起动的分段式控制策略

    Institute of Scientific and Technical Information of China (English)

    袁海宵

    2013-01-01

    The auxiliary power unit ( APU) is an important system of the civil aircraft for the aircraft safety and comfort. Large current output for long time will cause disadvantage effect on battery usage life. Also the too long start time will damage APU. So when start the APU by using the battery as the input power, for the purpose of re-ducing the damage to battery and APU, it is needed to start the APU in a shorter time by a lower battery output cur-rent. The subsection of power-current control strategy can start the APU in shorter time with the lowest damage to the battery and APU. This is important for extending the use life of APU and battery.%民用飞机辅助动力装置( APU)是保证飞机安全和舒适性的重要系统。大电流长时放电对蓄电池的使用寿命有不利影响,同时起动时间过长对APU也有不利影响。在使用蓄电池作为起动APU的功率来源时,为了减小对蓄电池和APU的损害,需要使用较小的蓄电池输出电流在较短的时间内将APU起动。采用功率-电流分段式控制的起动方式可以在较短的时间内,以对蓄电池和APU损伤最小的方式实现APU的起动。对延长蓄电池和APU使用寿命具有重要意义。

  8. 30 CFR 57.8534 - Shutdown or failure of auxiliary fans.

    Science.gov (United States)

    2010-07-01

    ... auxiliary fan failure due to malfunction, accident, power failure, or other such unplanned or unscheduled... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Shutdown or failure of auxiliary fans. 57.8534... Ventilation Underground Only § 57.8534 Shutdown or failure of auxiliary fans. (a) Auxiliary fans installed...

  9. A reliability centered maintenance model applied to the auxiliary feedwater system of a nuclear power plant; Um modelo de manutencao centrada em confiabilidade aplicada ao sistema de agua de alimentacaco auxiliar de uma usina nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Araujo, Jefferson Borges

    1998-01-15

    The main objective of maintenance in a nuclear power plant is to assure that structures, systems and components will perform their design functions with reliability and availability in order to obtain a safety and economic electric power generation. Reliability Centered Maintenance (RCM) is a method of systematic review to develop or optimize Preventive Maintenance Programs. This study presents the objectives, concepts, organization and methods used in the development of RCM application to nuclear power plants. Some examples of this application are included, considering the Auxiliary Feedwater System of a generic two loops PWR nuclear power plant of Westinghouse design. (author)

  10. Fuel Cell Powered Lift Truck

    Energy Technology Data Exchange (ETDEWEB)

    Moulden, Steve [Sysco Food Service, Houston, TX (United States)

    2015-08-20

    This project, entitled “Recovery Act: Fuel Cell-Powered Lift Truck Sysco (Houston) Fleet Deployment”, was in response to DOE funding opportunity announcement DE-PS36-08GO98009, Topic 7B, which promotes the deployment of fuel cell powered material handling equipment in large, multi-shift distribution centers. This project promoted large-volume commercialdeployments and helped to create a market pull for material handling equipment (MHE) powered fuel cell systems. Specific outcomes and benefits involved the proliferation of fuel cell systems in 5-to 20-kW lift trucks at a high-profile, real-world site that demonstrated the benefits of fuel cell technology and served as a focal point for other nascent customers. The project allowed for the creation of expertise in providing service and support for MHE fuel cell powered systems, growth of existing product manufacturing expertise, and promoted existing fuel cell system and component companies. The project also stimulated other MHE fleet conversions helping to speed the adoption of fuel cell systems and hydrogen fueling technology. This document also contains the lessons learned during the project in order to communicate the successes and difficulties experienced, which could potentially assist others planning similar projects.

  11. Digital Control of a power conditioner for fuel cell/super-capacitor hybrid system

    DEFF Research Database (Denmark)

    Caballero, Juan C Trujillo; Gomis-Bellmunt, Oriol; Montesinos-Miracle, Daniel;

    2014-01-01

    This article proposes a digital control scheme to operate a proton exchange membrane fuel cell module of 1.2 kW and a super-capacitor through a DC/DC hybrid converter. A fuel cell has been proposed as a primary source of energy, and a super-capacitor has been proposed as an auxiliary source of...... energy. Experimental validation of the system implemented in the laboratory is provided. Several tests have been performed to verify that the system achieves excellent output voltage (V0) regulation and super-capacitor voltage (V SC) control under disturbances from fuel cell power (PFC) and output power...

  12. Resolution of concerns in auxiliary feedwater piping

    International Nuclear Information System (INIS)

    Auxiliary feedwater piping systems at pressurized water reactor (PWR) nuclear power plants have experienced unanticipated operating conditions during plant operation. These unanticipated conditions have included plant events involving backleakage through check valves, temperatures in portions of the auxiliary feedwater piping system that exceed design conditions, and the occurrence of unanticipated severe fluid transients. The impact of these events has had an adverse effect at some nuclear stations on plant operation, installed plant components and hardware, and design basis calculations. Beaver Valley Unit 2, a three loop pressurized water reactor nuclear plant, has observed anomalies with the auxiliary feedwater system since the unit went operational in 1987. The consequences of these anomalies and plant events have been addressed and resolved for Beaver Valley Unit 2 by performing engineering and construction activities. These activities included pipe stress, pipe support and pipe rupture analysis, the monitoring of auxiliary feedwater system temperature and pressure, and the modification to plant piping, supports, valves, structures and operating procedures

  13. Auxiliary Deep Generative Models

    DEFF Research Database (Denmark)

    Maaløe, Lars; Sønderby, Casper Kaae; Sønderby, Søren Kaae;

    2016-01-01

    Deep generative models parameterized by neural networks have recently achieved state-of-the-art performance in unsupervised and semi-supervised learning. We extend deep generative models with auxiliary variables which improves the variational approximation. The auxiliary variables leave the...... generative model unchanged but make the variational distribution more expressive. Inspired by the structure of the auxiliary variable we also propose a model with two stochastic layers and skip connections. Our findings suggest that more expressive and properly specified deep generative models converge...... faster with better results. We show state-of-the-art performance within semi-supervised learning on MNIST (0.96%), SVHN (16.61%) and NORB (9.40%) datasets....

  14. Clean, Efficient, and Reliable Heat and Power for the 21st Century, Fuel Cell Technologies Program (FCTP) (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)

    2010-05-01

    This overview of the U.S. Department of Energy's Fuel Cell Technologies Program describes the program's focus and goals, along with current fuel cell applications and future potential. The program focuses on research and development of fuel cell systems for diverse applications in the stationary power, portable power, and transportation sectors. It works to reduce costs and improve technologies to advance fuel cell uses in areas such as combined heat and power, auxiliary power units, portable power systems, and stationary and backup power. To help ensure that fuel cell advances are realized, the program rigorously analyzes energy efficiency, economic, and environmental benefits of fuel cells and seeks to optimize synergies among fuel cell applications and other renewable technologies.

  15. PS auxiliary magnet

    CERN Multimedia

    1974-01-01

    Units of the PS auxiliary magnet system. The picture shows how the new dipoles, used for vertical and horizontal high-energy beam manipulation, are split for installation and removal so that it is not necessary to break the accelerator vacuum. On the right, adjacent to the sector valve and the windings of the main magnet, is an octupole of the set.

  16. Dental Auxiliary Occupations. Interim Report.

    Science.gov (United States)

    Kingston, Richard D.

    As part of a dental auxiliaries project, a Dental Auxiliary National Technical Advisory Committee was established, and its major undertaking was to assist in the development of a functional inventory for each of the three dental auxiliary occupations (dental assisting, dental hygiene, and dental laboratory technology). The analysis consisted of…

  17. Transport in Auxiliary Heated NSTX Discharges

    International Nuclear Information System (INIS)

    The NSTX spherical torus (ST) provides a unique platform to investigate magnetic confinement in auxiliary-heated plasmas at low aspect ratio. Auxiliary power is routinely coupled to ohmically heated plasmas by deuterium neutral-beam injection (NBI) and by high-harmonic fast waves (HHFW) launch. While theory predicts both techniques to preferentially heat electrons, experiment reveals the electron temperature is greater than the ion temperature during HHFW, but the electron temperature is less than the ion temperature during NBI. In the following we present the experimental data and the results of transport analyses

  18. National Ignition Facility subsystem design requirements laser auxiliary subsystem SSDR 1.3.5

    International Nuclear Information System (INIS)

    This system design requirement document establishes the performance, design, development and test requirements for the NIF Laser Auxiliary Systems. The Laser Auxiliary Systems consist of: a. Gas Cooling System; b. Low conductivity cooling water system; C. Deionized cooling water system; d. Electrical power distribution system. The gas cooling system will be used for cooling the main laser amplifier flashlamps and some smaller quantities will be used for purging Pockels cells and for diode pumps in preamplifier. The low conductivity cooling water system will be used for cooling the capacitor banks. The deionized cooling water system will be used to cool the multi-pass amplifier in the OPG PAM. Electrical power will be required for the OPG systems, Pockels cells, power conditioning, and amplifier support equipment

  19. Low emission fuel cell ship. Environmental account of fuel cell powered ships

    International Nuclear Information System (INIS)

    Shipping is the dominant mode of global transport, accounting for total global anthropogenic NOx and SOx emissions of 10-14% and 4-6% respectively. Future environmental requirements signalled for shipping may exceed the possibilities within current conventional technology. The work presented document the environmental benefits of using fuel cells compared to diesel engines. The work describes the general principles for modelling emissions to air for ships. The model was calibrated by measurements onboard an offshore supply vessel and a car carrier. For the offshore vessel, the FC model includes 100% of onboard power delivered by FC's. For the car carrier, the FC replaces the auxiliary engines. FC type modelled was a high temperature FC running on natural gas. The work quantifies yearly reduction in atmospheric emissions of CO2, NOx, SOx and PM. Our results show that the installation of fuel cells in ships will improve the environmental performance significantly (e.g. global warming and acidification). (author)

  20. 机车辅助电源电快速瞬变脉冲群试验案例分析%Investigation on Locomotive Auxiliary Power in EFT Testing Cases

    Institute of Scientific and Technical Information of China (English)

    窦爱玉; 赵阳; 颜伟; 慈文彦; 王珏

    2014-01-01

    The mechanism of production and harassment to EFT is employed to investigate the EFT problems of the locomotive auxiliary power. This paper studies the processing method and puts forward the solution to EFT problems of power line and IGBT. The experimental results show that, the EFT level of locomotive auxiliary power is efficiently improved,conformable to GB/T17626. 4-2008.%针对机车辅助电源电快速瞬变脉冲群( EFT)抗扰度问题,分析了脉冲群产生和骚扰机理,研究了脉冲群的处理方法,提出了针对电源线EFT问题的解决方法.试验结果表明,所提方法可以有效提高机车辅助电源EFT抗扰度等级,达到GB/T 17626.4—2008标准要求.

  1. Hydrogen Fuel Cell Performance as Telecommunications Backup Power in the United States

    Energy Technology Data Exchange (ETDEWEB)

    Kurtz, Jennifer [National Renewable Energy Lab. (NREL), Golden, CO (United States); Saur, Genevieve [National Renewable Energy Lab. (NREL), Golden, CO (United States); Sprik, Sam [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2015-03-01

    Working in collaboration with the U.S. Department of Energy (DOE) and industry project partners, the National Renewable Energy Laboratory (NREL) acts as the central data repository for the data collected from real-world operation of fuel cell backup power systems. With American Recovery and Reinvestment Act of 2009 (ARRA) co-funding awarded through DOE's Fuel Cell Technologies Office, more than 1,300 fuel cell units were deployed over a three-plus-year period in stationary, material handling equipment, auxiliary power, and backup power applications. This surpassed a Fuel Cell Technologies Office ARRA objective to spur commercialization of an early market technology by installing 1,000 fuel cell units across several different applications, including backup power. By December 2013, 852 backup power units out of 1,330 fuel cell units deployed were providing backup service, mainly for telecommunications towers. For 136 of the fuel cell backup units, project participants provided detailed operational data to the National Fuel Cell Technology Evaluation Center for analysis by NREL's technology validation team. NREL analyzed operational data collected from these government co-funded demonstration projects to characterize key fuel cell backup power performance metrics, including reliability and operation trends, and to highlight the business case for using fuel cells in these early market applications. NREL's analyses include these critical metrics, along with deployment, U.S. grid outage statistics, and infrastructure operation.

  2. Water reactive hydrogen fuel cell power system

    Science.gov (United States)

    Wallace, Andrew P; Melack, John M; Lefenfeld, Michael

    2014-01-21

    A water reactive hydrogen fueled power system includes devices and methods to combine reactant fuel materials and aqueous solutions to generate hydrogen. The generated hydrogen is converted in a fuel cell to provide electricity. The water reactive hydrogen fueled power system includes a fuel cell, a water feed tray, and a fuel cartridge to generate power for portable power electronics. The removable fuel cartridge is encompassed by the water feed tray and fuel cell. The water feed tray is refillable with water by a user. The water is then transferred from the water feed tray into a fuel cartridge to generate hydrogen for the fuel cell which then produces power for the user.

  3. Progress on radio frequency auxiliary heating system designs in ITER

    International Nuclear Information System (INIS)

    ITER will require over 100 MW of auxiliary power for heating, on- and off-axis current drive, accessing the H-mode, and plasma shut-down. The Electron Cyclotron Range of Frequencies (ECRF) and Ion Cyclotron Range of Frequencies (ICRF) are two forms of Radio Frequency (RF) auxiliary power being developed for these applications. Design concepts for both the ECRF and ICRF systems are presented, key features and critical design issues are discussed, and projected performances outlined

  4. TDDFT screening auxiliary withdrawing group and design the novel D-A-π-A organic dyes based on indoline dye for highly efficient dye-sensitized solar cells.

    Science.gov (United States)

    Yang, Zhenqing; Liu, Yun; Liu, Chunmeng; Lin, Chundan; Shao, Changjin

    2016-10-01

    Based on the experimentally synthesized dye JZ145, we designed a series of novel D-A-π-A dyes SPL201-SPL211 with different π-conjugated bridges and a new auxiliary withdrawing group for highly efficient dye-sensitized solar cells (DSSCs) using density functional theory (DFT) and time-dependent DFT(TDDFT). The molecular structures, energy levels, absorption spectra, light-harvesting efficiency (LHE), driving force of injection(ΔGinj) and regeneration(ΔGreg), electron dipole moment (μnormal) and lifetime of the first excited state(τ) were all scrutinized in details. Results reveal that the additional withdrawing group A2 and the π-conjugated group di-η-hexyl-substituted cyclopentadithiophene (CPDT) are more promising functional groups for the organic dyes with D-A-π-A structure. We further designed SPL212 and SPL213 by employing indoline group as donor, the above screened functional groups as π-conjugated bridge and additional withdrawing group, biscarbodithiolic acid and dicyanovinyl sulfonic acid groups as acceptor group. We found that SPL212 exhibits not only a higher molar extinction coefficient with an increment of 30.8%, larger excited state lifetime and an obvious redshift of 201nm but also a broader absorption spectrum covering the entire visible range even up to near-IR of 1200nm compared to JZ145. So, SPL212 can be used as a promising candidate for DSSCs. In addition, the results also prove that biscarbodithiolic acid may be more favorable than dicyanovinylsulfonic acid as acceptor group in DSSCs. PMID:27269476

  5. Engine Auxiliary System Guideline: Cooling Systems

    OpenAIRE

    Kela, Suvi

    2015-01-01

    The thesis was done for Wärtsilä Technical Services organization. The assignment was to consolidate a guideline for cooling systems as an engine auxiliary system covering the Wärtsilä 4-stroke engines currently in production. The guideline was to include information considering both marine and power plants installations. The sources of information were internal documentation from Wärtsilä, literature review and discussions with Wärtsilä cooling system experts. The guideline includes informati...

  6. High power density carbonate fuel cell

    Energy Technology Data Exchange (ETDEWEB)

    Yuh, C.; Johnsen, R.; Doyon, J.; Allen, J. [Energy Research Corp., Danbury, CT (United States)

    1996-12-31

    Carbonate fuel cell is a highly efficient and environmentally clean source of power generation. Many organizations worldwide are actively pursuing the development of the technology. Field demonstration of multi-MW size power plant has been initiated in 1996, a step toward commercialization before the turn of the century, Energy Research Corporation (ERC) is planning to introduce a 2.85MW commercial fuel cell power plant with an efficiency of 58%, which is quite attractive for distributed power generation. However, to further expand competitive edge over alternative systems and to achieve wider market penetration, ERC is exploring advanced carbonate fuel cells having significantly higher power densities. A more compact power plant would also stimulate interest in new markets such as ships and submarines where space limitations exist. The activities focused on reducing cell polarization and internal resistance as well as on advanced thin cell components.

  7. Regulation of Power Conversion in Fuel Cells

    Institute of Scientific and Technical Information of China (English)

    SHEN Mu-zhong; ZHANG J.; K. Scott

    2004-01-01

    Here we report a regulation about power conversion in fuel cells. This regulation is expressed as that total power produced by fuel cells is always proportional to the square of the potential difference between the equilibrium potential and work potential. With this regulation we deduced fuel cell performance equation which can describe the potential vs. the current performance curves, namely, polarization curves of fuel cells with three power source parameters: equilibrium potential E0; internal resistance R; and power conversion coefficient K. The concept of the power conversion coefficient is a new criterion to evaluate and compare the characteristics and capacity of different fuel cells. The calculated values obtained with this equation agree with practical performance of different types of fuel cells.

  8. A Parallel Auxiliary Grid AMG Method for GPU

    OpenAIRE

    Wang, Lu; Hu, Xiaozhe; Cohen, Jonathan; Xu, Jinchao

    2012-01-01

    In this paper, we develop a new parallel auxiliary grid algebraic multigrid (AMG) method to leverage the power of graphic processing units (GPUs). In the construction of the hierarchical coarse grid, we use a simple and fixed coarsening procedure based on a region quadtree generated from an auxiliary grid. This allows us to explicitly control the sparsity patterns and operator complexities of the AMG solver. This feature provides (nearly) optimal load balancing and predictable communication p...

  9. SEPP-ZVS High Frequency Inverter Incorporating Auxiliary Switch

    Science.gov (United States)

    Ogiwara, Hiroyuki; Itoi, Misao; Nakaoka, Mutsuo

    This paper presents a novel circuit topology to attain ZVS operation of a high frequency inverter over a wide range output power regulation using a PWM control technique by connecting an auxiliary switch to the conventional single ended push-pull (SEPP) ZVS high frequency inverter. A switching current is injected into the main switches via the auxiliary switch only during the short period between its turn-on and off times to supply a current required for its ZVS operation.

  10. Micro space power system using MEMS fuel cell for nano-satellites

    Science.gov (United States)

    Lee, Jongkwang; Kim, Taegyu

    2014-08-01

    A micro space power system using micro fuel cell was developed for nano-satellites. The power system was fabricated using microelectromechanical system (MEMS) fabrication technologies. Polymer electrolyte membrane (PEM) fuel cell was selected in consideration of space environment. Sodium borohydride (NaBH4) was selected as a hydrogen source while hydrogen peroxide (H2O2) was selected as an oxygen source. The power system consists of a micro fuel cell, micro-reactor, micro-pump, and fuel cartridges. The micro fuel cell was fabricated on a light-weight and corrosion-resistant glass plates. The micro-reactor was used to generate hydrogen from NaBH4 alkaline solution via a catalytic hydrolysis reaction. All components such as micro-pump, fuel cartridges, and auxiliary battery were integrated for a complete power system. The storability of NaBH4 solution was evaluated at -25 °C and the performance of the micro power system was measured at various operating conditions. The power output of micro power system reasonably followed up the given electric load conditions.

  11. System Studies of Fuel Cell Power Plants

    OpenAIRE

    Kivisaari, Timo

    2001-01-01

    This thesis concerns system studies of power plants wheredifferent types of fuel cells accomplish most of the energyconversion. Ever since William Grove observed the fuel cell effect inthe late 1830s fuel cells have been the subject or more or lessintense research and development. Especially in the USA theseactivities intensified during the second part of the 1950s,resulting in the development of the fuel cells used in theApollo-program. Swedish fuel cell activities started in themid-1960s, w...

  12. System Study: Auxiliary Feedwater 1998–2013

    Energy Technology Data Exchange (ETDEWEB)

    Schroeder, John Alton [Idaho National Lab. (INL), Idaho Falls, ID (United States). Risk Assessment and Management Services Dept.

    2014-12-31

    This report presents an unreliability evaluation of the auxiliary feedwater (AFW) system at 69 U.S. commercial nuclear power plants. Demand, run hours, and failure data from fiscal year 1998 through 2013 for selected components were obtained from the Institute of Nuclear Power Operations (INPO) Consolidated Events Database (ICES). The unreliability results are trended for the most recent 10-year period while yearly estimates for system unreliability are provided for the entire active period. No statistically significant increasing or decreasing trends were identified in the AFW results.

  13. System Study: Auxiliary Feedwater 1998-2014

    Energy Technology Data Exchange (ETDEWEB)

    Schroeder, John Alton [Idaho National Lab. (INL), Idaho Falls, ID (United States). Risk Assessment and Management Services Dept.

    2015-12-01

    This report presents an unreliability evaluation of the auxiliary feedwater (AFW) system at 69 U.S. commercial nuclear power plants. Demand, run hours, and failure data from fiscal year 1998 through 2014 for selected components were obtained from the Institute of Nuclear Power Operations (INPO) Consolidated Events Database (ICES). The unreliability results are trended for the most recent 10 year period while yearly estimates for system unreliability are provided for the entire active period. No statistically significant increasing or decreasing trends were identified in the AFW results.

  14. Biofuel Cells – Alternative Power Sources

    International Nuclear Information System (INIS)

    Energy generation from renewable sources and effective waste treatment are two key challenges for the sustainable development. Microbiological (or Bio-) Fuel Cells provide an elegant solution by linking both tasks. Biofuel cells, which can directly generate electricity from biodegradable substances, have rapidly gained increasing research attention. Widely available fuel sources and moderate operational conditions make them promising in renewable energy generation, wastewater treatment, power sources for remote devices, etc. This paper reviews the use of microorganisms as biocatalysts in microbiological fuel cells. The principle of biofuel cells and their construction elements are discussed. Keywords: alternative power sources, biofuel cells, biocatalysts

  15. WMO Selected, Supplemenatary, Auxiliary Ships

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — World Meteorological Organization International List of Selected, Supplementary and Auxiliary Ships, recognized as Publication 47. 1973-1998 editions, gathered from...

  16. Design of Power Shift Auxiliary Gearbox in Transmission for Tractor%拖拉机负载增扭/梭行换挡副变速器设计

    Institute of Scientific and Technical Information of China (English)

    高翔; 王志晨

    2016-01-01

    动力换挡变速器换挡时动力不中断,且能够将复杂的换挡过程简化为按钮操作,在国外的拖拉机上已得到了广泛应用。为此,设计了一种新型的负载换挡行星齿轮副变速器,增加了原变速箱的挡位数,并实现了增扭负载换挡与梭行换挡。在分析了整体功能要求的基础上,确定了变速器的传动方案及结构,设计了副变速器液压控制系统,并对拖拉机各挡总传动比及理论车速进行了设计计算。同时,绘制了拖拉机牵引力和比油耗曲线,定义拖拉机牵引功率利用率和比油耗损失率用以评价拖拉机动力性和燃油经济性,并通过计算比较了改进前后拖拉机的动力性和燃油经济性情况。%With the advantage of uninterrupted output power in the process of gear shift, power shift transmission is wide-ly used on Tractor abroad.In this paper, a new type power shift auxiliary gearbox is developed.The new type auxiliary gearbox increases the number of gear positions and has the function of torque booster and shuttle shift.Based on the anal-ysis of function requirements, the general drive scheme and structural style is obtained.The hydraulic control system is designed, and gear ratios and theoretical travel speeds are calculated.The tractor traction and specific fuel consumption curves are drawn.The traction power utilization and specific fuel consumption loss rate is defined to evaluate the tractor dynamic and fuel economy performance .The tractor dynamic and fuel economy performance of original tractor and im-proved tractor is compared through calculation.

  17. Current State of Technology of Fuel Cell Power Systems for Autonomous Underwater Vehicles

    Directory of Open Access Journals (Sweden)

    Alejandro Mendez

    2014-07-01

    Full Text Available Autonomous Underwater Vehicles (AUVs are vehicles that are primarily used to accomplish oceanographic research data collection and auxiliary offshore tasks. At the present time, they are usually powered by lithium-ion secondary batteries, which have insufficient specific energies. In order for this technology to achieve a mature state, increased endurance is required. Fuel cell power systems have been identified as an effective means to achieve this endurance but no implementation in a commercial device has yet been realized. This paper summarizes the current state of development of the technology in this field of research. First, the most adequate type of fuel cell for this application is discussed. The prototypes and design concepts of AUVs powered by fuel cells which have been developed in the last few years are described. Possible commercial and experimental fuel cell stack options are analyzed, examining solutions adopted in the analogous aerial vehicle applications, as well as the underwater ones, to see if integration in an AUV is feasible. Current solutions in oxygen and hydrogen storage systems are overviewed and energy density is objectively compared between battery power systems and fuel cell power systems for AUVs. A couple of system configuration solutions are described including the necessary lithium-ion battery hybrid system. Finally, some closing remarks on the future of this technology are given.

  18. Research and Application of Auxiliary Optimization Technology of Power Grid Accident Processing Based on the Mode of Regulation and Control Integration

    Directory of Open Access Journals (Sweden)

    Cui Houzhen

    2015-01-01

    Full Text Available Accident processing is the most important link of the scheduling of daily monitoring. The improvement of intelligent level is of great significance for improving the efficiency of accident processing scheduling, shortening the time of accident processing and preventing further deterioration of accidents. According to features of accident processing scheduling, this paper puts forward an integrated framework of aid decision-making of online accident processing based on large power grid, and carries out a study from five aspects, namely integrated information support platform, risk perception in advance, online fault diagnosis, aid decision-making afterwards and visual display, so as to conduct real-time tracking on operating state of power grid, eliminate potential safety hazards of power grid and upgrade power grid from “manual analysis” scheduling to “intelligent analysis” scheduling.

  19. Scheduling of Power System Cells Integrating Stochastic Power Generation

    International Nuclear Information System (INIS)

    Energy supply and climate change are nowadays two of the most outstanding problems which societies have to cope with under a context of increasing energy needs. Public awareness of these problems is driving political willingness to take actions for tackling them in a swift and efficient manner. Such actions mainly focus in increasing energy efficiency, in decreasing dependence on fossil fuels, and in reducing greenhouse gas emissions. In this context, power systems are undergoing important changes in the way they are planned and managed. On the one hand, vertically integrated structures are being replaced by market structures in which power systems are un-bundled. On the other, power systems that once relied on large power generation facilities are witnessing the end of these facilities' life-cycle and, consequently, their decommissioning. The role of distributed energy resources such as wind and solar power generators is becoming increasingly important in this context. However, the large-scale integration of such type of generation presents many challenges due, for instance, to the uncertainty associated to the variability of their production. Nevertheless, advanced forecasting tools may be combined with more controllable elements such as energy storage devices, gas turbines, and controllable loads to form systems that aim to reduce the impacts that may be caused by these uncertainties. This thesis addresses the management under market conditions of these types of systems that act like independent societies and which are herewith named power system cells. From the available literature, a unified view of power system scheduling problems is also proposed as a first step for managing sets of power system cells in a multi-cell management framework. Then, methodologies for performing the optimal day-ahead scheduling of single power system cells are proposed, discussed and evaluated under both a deterministic and a stochastic framework that directly integrates the

  20. Air breathing lithium power cells

    Science.gov (United States)

    Farmer, Joseph C.

    2014-07-15

    A cell suitable for use in a battery according to one embodiment includes a catalytic oxygen cathode; a stabilized zirconia electrolyte for selective oxygen anion transport; a molten salt electrolyte; and a lithium-based anode. A cell suitable for use in a battery according to another embodiment includes a catalytic oxygen cathode; an electrolyte; a membrane selective to molecular oxygen; and a lithium-based anode.

  1. 基于年费用法的电站辅机投资项目经济评价研究%Economic Evaluation of Auxiliary Equipment Project in Power Plants Based on the Annualized Cost Method

    Institute of Scientific and Technical Information of China (English)

    陈晓霞

    2013-01-01

    The economic evaluation is an important part of feasibility study and project proposals. It also can help making decision. The thesis, in accordance with characteristics of the electric power project and the specific property of evaluation, analyzes the component elements, establishes evaluating indicator, and constructs economic assessment method of auxiliary equipment project in power plants. Through empirical analysis, scientific and practiced characters of index system and evaluating method have been validated.%  经济评价是电力项目可行性研究与项目建议书的重要组成部分,是项目决策科学化的据。论文从电站辅机项目的特点和评价独特性入手,分析和甄别构成要素、设置评价指标,构建了基年费用法的电站辅机设备的经济性评价方法,并通过实证分析,验证了指标体系和评价方法的科学性和实践可行性。

  2. A portable system powered with hydrogen and one single air-breathing PEM fuel cell

    International Nuclear Information System (INIS)

    Highlights: • A portable system based on hydrogen and single air breathing PEM fuel cell. • Control electronics designed for low single cell voltage (0.5–0.8 V). • Forced air convection and anode purging required to help water management. • Application consisting of a propeller able to display a luminous message. • Up to 20 h autonomy with continuous 1.1 W consumption, using 1 g H2. - Abstract: A portable system for power generation based on hydrogen and a single proton exchange membrane fuel cell (PEMFC) has been built and operated. The fuel cell is fed in the anode with hydrogen stored in a metal hydrides cartridge, and in the cathode with oxygen from quiescent ambient air (‘air breathing’). The control electronics of the system performs DC–DC conversion from the low voltage (0.5–0.8 V) and high current output (200–300 mA cm−2) of the single fuel cell, up to 3.3 V to power an electronic application. System components assist fuel cell operation, including an electronic valve for anode purging, a fan in front of the open cathode, two supercapacitors for auxiliary power requirements, four LED lights, and a display screen. The influence of the system components on fuel cell behaviour is analyzed. The cathode fan and anodic purging help excess water removal from the electrodes leading to steadier cell response at the expense of extra power consumption. The power system is able to provide above 1 W DC electricity to an external application during 20 h using 1 g of H2. An application consisting of a propeller able to display a luminous message is chosen to test system. It is shown that one single air breathing PEM fuel cell powered with hydrogen may provide high energy density and autonomy for portable applications

  3. Exoelectrogenic bacteria that power microbial fuel cells

    KAUST Repository

    Logan, Bruce E.

    2009-03-30

    There has been an increase in recent years in the number of reports of microorganisms that can generate electrical current in microbial fuel cells. Although many new strains have been identified, few strains individually produce power densities as high as strains from mixed communities. Enriched anodic biofilms have generated power densities as high as 6.9 W per m2 (projected anode area), and therefore are approaching theoretical limits. To understand bacterial versatility in mechanisms used for current generation, this Progress article explores the underlying reasons for exocellular electron transfer, including cellular respiration and possible cell-cell communication.

  4. Fuel-Cell-Powered Vehicle with Hybrid Power Management

    Science.gov (United States)

    Eichenberg, Dennis J.

    2010-01-01

    Figure 1 depicts a hybrid electric utility vehicle that is powered by hydrogenburning proton-exchange-membrane (PEM) fuel cells operating in conjunction with a metal hydride hydrogen-storage unit. Unlike conventional hybrid electric vehicles, this vehicle utilizes ultracapacitors, rather than batteries, for storing electric energy. This vehicle is a product of continuing efforts to develop the technological discipline known as hybrid power management (HPM), which is oriented toward integration of diverse electric energy-generating, energy-storing, and energy- consuming devices in optimal configurations. Instances of HPM were reported in five prior NASA Tech Briefs articles, though not explicitly labeled as HPM in the first three articles: "Ultracapacitors Store Energy in a Hybrid Electric Vehicle" (LEW-16876), Vol. 24, No. 4 (April 2000), page 63; "Photovoltaic Power Station With Ultracapacitors for Storage" (LEW- 17177), Vol. 27, No. 8 (August 2003), page 38; "Flasher Powered by Photovoltaic Cells and Ultracapacitors" (LEW-17246), Vol. 27, No. 10 (October 2003), page 37; "Hybrid Power Management" (LEW-17520), Vol. 29, No. 12 (December 2005), page 35; and "Ultracapacitor-Powered Cordless Drill" (LEW-18116-1), Vol. 31, No. 8 (August 2007), page 34. To recapitulate from the cited prior articles: The use of ultracapacitors as energy- storage devices lies at the heart of HPM. An ultracapacitor is an electrochemical energy-storage device, but unlike in a conventional rechargeable electrochemical cell or battery, chemical reactions do not take place during operation. Instead, energy is stored electrostatically at an electrode/electrolyte interface. The capacitance per unit volume of an ultracapacitor is much greater than that of a conventional capacitor because its electrodes have much greater surface area per unit volume and the separation between the electrodes is much smaller.

  5. Improving Energy Efficiency of Auxiliaries

    International Nuclear Information System (INIS)

    The summaries of this report are: Economics Ultimately Dictates Direction; Electric Auxiliaries Provide Solid Benefits. The Impact on Vehicle Architecture Will be Important; Integrated Generators With Combined With Turbo Generators Can Meet the Electrical Demands of Electric Auxiliaries; Implementation Will Follow Automotive 42V Transition; Availability of Low Cost Hardware Will Slow Implementation; Industry Leadership and Cooperation Needed; Standards and Safety Protocols Will be Important. Government Can Play an Important Role in Expediting: Funding Technical Development; Incentives for Improving Fuel Economy; Developing Standards, Allowing Economy of Scale; and Providing Safety Guidelines

  6. Portable power applications of fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Weston, M.; Matcham, J.

    2002-07-01

    This report describes the state-of-the-art of fuel cell technology for portable power applications. The study involved a comprehensive literature review. Proton exchange membrane fuel cells (PEMFCs) have attracted much more interest than either direct methanol fuel cells (DMFCs) or solid oxide fuel cells (SOFCs). However, issues relating to fuel choice and catalyst design remain with PEMFCs; DMFCs have excellent potential provided issues relating to the conducting membrane can be resolved but the current high temperature of operation and low power density currently makes SOFCs less applicable to portable applications. Available products are listed and the obstacles to market penetration are discussed. The main barriers are cost and the size/weight of fuel cells compared with batteries. Another key problem is the lack of a suitable fuel infrastructure.

  7. Use of super-capacitors in the motorization of fuel cell electric powered vehicles; Utilisation de supercondensateurs dans la motorisation de vehicules electriques a pile a combustible

    Energy Technology Data Exchange (ETDEWEB)

    Djerdir, A.; Gualous, H.; Berthon, A. [L2ES, IGE, 90 - Belfort (France); Bouquain, D. [CREEBEL, 90 - Belfort (France); Ayad, M.Y.; Rasoanarivo, I.; Rael, S.; Davat, B. [GREEN, 54 - Vandoeuvre les Nancy (France)

    2000-07-01

    The aim of this work is to integrate super-capacitors in a fuel cell vehicle as an auxiliary energy source able to provide and to recover an energy power. The super-capacitors elements are got together in series/parallel and inserted on-board of the vehicle. A tension level and an energy converter/packager have been chosen. (O.M.)

  8. POWERED LED LIGHTING SUPPLIED FROM PV CELLS

    Directory of Open Access Journals (Sweden)

    Tirshu M.

    2011-12-01

    Full Text Available The paper deals with practical realization of efficient lighting system based on LED’s of 80W total power mounted on corridor ceiling total length of which is 120m and substitutes existing traditional lighting system consisting of 29 lighting blocks with 4 fluorescent lamps each of them and summary power 2088W. Realized lighting system is supplied from two photovoltaic panels of power 170W. Generated energy by PV cells is accumulated in two accumulators of 75Ah capacity and from battery by means of specialized convertor is applied to lighting system. Additionally, paper present data measured by digital weather station (solar radiation and UV index, which is mounted near of PV cells and comparative analyze of solar energy with real energy generated by PV cells is done. Measured parameters by digital weather station are stored by computer in on-line mode.

  9. Experimental study of a fuel cell power train for road transport application

    Science.gov (United States)

    Corbo, P.; Corcione, F. E.; Migliardini, F.; Veneri, O.

    The development of fuel cell electric vehicles requires the on-board integration of fuel cell systems and electric energy storage devices, with an appropriate energy management system. The optimization of performance and efficiency needs an experimental analysis of the power train, which has to be effected in both stationary and transient conditions (including standard driving cycles). In this paper experimental results concerning the performance of a fuel cell power train are reported and discussed. In particular characterization results for a small sized fuel cell system (FCS), based on a 2.5 kW PEM stack, alone and coupled to an electric propulsion chain of 3.7 kW are presented and discussed. The control unit of the FCS allowed the main stack operative parameters (stoichiometric ratio, hydrogen and air pressure, temperature) to be varied and regulated in order to obtain optimized polarization and efficiency curves. Experimental runs effected on the power train during standard driving cycles have allowed the performance and efficiency of the individual components (fuel cell stack and auxiliaries, dc-dc converter, traction batteries, electric engine) to be evaluated, evidencing the role of output current and voltage of the dc-dc converter in directing the energy flows within the propulsion system.

  10. Direct FuelCell/Turbine Power Plant

    Energy Technology Data Exchange (ETDEWEB)

    Hossein Ghezel-Ayagh

    2008-09-30

    This report summarizes the progress made in development of Direct FuelCell/Turbine (DFC/T{reg_sign}) power plants for generation of clean power at very high efficiencies. The DFC/T system employs an indirectly heated Turbine Generator to supplement fuel cell generated power. The concept extends the high efficiency of the fuel cell by utilizing the fuel cell's byproduct heat in a Brayton cycle. Features of the DFC/T system include: electrical efficiencies of up to 75% on natural gas, minimal emissions, reduced carbon dioxide release to the environment, simplicity in design, direct reforming internal to the fuel cell, and potential cost competitiveness with existing combined cycle power plants. Proof-of-concept tests using a sub-MW-class DFC/T power plant at FuelCell Energy's (FCE) Danbury facility were conducted to validate the feasibility of the concept and to measure its potential for electric power production. A 400 kW-class power plant test facility was designed and retrofitted to conduct the tests. The initial series of tests involved integration of a full-size (250 kW) Direct FuelCell stack with a 30 kW Capstone microturbine. The operational aspects of the hybrid system in relation to the integration of the microturbine with the fuel cell, process flow and thermal balances, and control strategies for power cycling of the system, were investigated. A subsequent series of tests included operation of the sub-MW Direct FuelCell/Turbine power plant with a Capstone C60 microturbine. The C60 microturbine extended the range of operation of the hybrid power plant to higher current densities (higher power) than achieved in initial tests using the 30kW microturbine. The proof-of-concept test results confirmed the stability and controllability of operating a fullsize (250 kW) fuel cell stack in combination with a microturbine. Thermal management of the system was confirmed and power plant operation, using the microturbine as the only source of fresh air supply

  11. Hydraulic turbines and auxiliary equipment

    Energy Technology Data Exchange (ETDEWEB)

    Luo Gaorong [Organization of the United Nations, Beijing (China). International Centre of Small Hydroelectric Power Plants

    1995-07-01

    This document presents a general overview on hydraulic turbines and auxiliary equipment, emphasizing the turbine classification, in accordance with the different types of turbines, standard turbine series in China, turbine selection based on the basic data required for the preliminary design, general hill model curves, chart of turbine series and the arrangement of application for hydraulic turbines, hydraulic turbine testing, and speed regulating device.

  12. Heat transfer equipment performance diagnosis of auxiliary systems in electric power stations; Diagnostico de comportamiento de equipo de transferencia de calor de sistemas auxiliares de centrales termoelectricas

    Energy Technology Data Exchange (ETDEWEB)

    Ruiz Esparza Gutierrez, Rogelio [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1990-12-31

    In this article the methodology followed to diagnose the performance of the equipment where heat is transferred from the feed water, condensate and circulation water systems in fossil power plants (FPP). The data collection is made with the unit in normal operation, using local instrumentation without taking the equipment out of service for its installation. The equipment diagnosis is made through the analysis of the collected data in actual operation and the design data; for this purpose a thermal balance of the interested systems is performed to obtain all the conditions an operation data. Later on the performance indicative parameters (PIP) of actual operation and design are calculated and compared one against the other. Such a comparison reveals the performance deterioration and the possible equipment faults. The data obtained and the supplementary information are stored in a data base whose objective is that Comision Federal de Electricidad has on hand a prompt access to them in order to control the performance, compare them among similar units and power stations, and inclusively verify possible recurrent causes of low availability in the referred systems. [Espanol] En este articulo se presenta la metodologia seguida para diagnosticar el comportamiento de equipos en los que se transfiere calor de los sistemas de agua de alimentacion, condensado y circulacion de las centrales termoelectricas (CTE). La toma de datos se realiza con la unidad en operacion normal, utilizando instrumentacion local sin necesidad de sacar de servicio a los equipos para su instalacion, ya que se ocupan los mismos puntos para instrumentos con que cuentan por diseno. El diagnostico de los equipos se realiza mediante el analisis de los datos recopilados, tanto de operacion real como de diseno; para ello, se efectua un balance termico de los sistemas de interes para obtener todas las condiciones y los datos de operacion. Posteriormente, se calculan los parametros indicativos de

  13. POWERED LED LIGHTING SUPPLIED FROM PV CELLS

    OpenAIRE

    Tirshu M.; Uzun M; Speian A.; Spivac V.; Bogdan A.

    2011-01-01

    The paper deals with practical realization of efficient lighting system based on LED’s of 80W total power mounted on corridor ceiling total length of which is 120m and substitutes existing traditional lighting system consisting of 29 lighting blocks with 4 fluorescent lamps each of them and summary power 2088W. Realized lighting system is supplied from two photovoltaic panels of power 170W. Generated energy by PV cells is accumulated in two accumulators of 75Ah capacity and from battery by me...

  14. High Efficiency Reversible Fuel Cell Power Converter

    DEFF Research Database (Denmark)

    Pittini, Riccardo

    traditional unidirectional fuel cell, bidirectional fuel cells have increased operating voltage and current ranges. These characteristics increase the stresses on dc-dc and dc-ac converters in the electrical system, which require proper design and advanced optimization. This work is part of the PhD project......The large scale integration of renewable energy sources requires suitable energy storage systems to balance energy production and demand in the electrical grid. Bidirectional fuel cells are an attractive technology for energy storage systems due to the high energy density of fuel. Compared to...... entitled "High Efficiency Reversible Fuel Cell Power Converter" and it presents the design of a high efficiency dc-dc converter developed and optimized for bidirectional fuel cell applications. First, a brief overview of fuel cell and energy storage technologies is presented. Different system topologies as...

  15. Stationary power fuel cell commercialization status worldwide

    Energy Technology Data Exchange (ETDEWEB)

    Williams, M.C. [Dept. of Energy, Morgantown, WV (United States)

    1996-12-31

    Fuel cell technologies for stationary power are set to play a role in power generation applications worldwide. The worldwide fuel cell vision is to provide powerplants for the emerging distributed generation and on-site markets. Progress towards commercialization has occurred in all fuel cell development areas. Around 100 ONSI phosphoric acid fuel cell (PAFC) units have been sold, with significant foreign sales in Europe and Japan. Fuji has apparently overcome its PAFC decay problems. Industry-driven molten carbonate fuel cell (MCFC) programs in Japan and the U.S. are conducting megawatt (MW)-class demonstrations, which are bringing the MCFC to the verge of commercialization. Westinghouse Electric, the acknowledged world leader in tubular solid oxide fuel cell (SOFC) technology, continues to set performance records and has completed construction of a 4-MW/year manufacturing facility in the U.S. Fuel cells have also taken a major step forward with the conceptual development of ultra-high efficiency fuel cell/gas turbine plants. Many SOFC developers in Japan, Europe, and North America continue to make significant advances.

  16. A magnetorheological clutch for efficient automotive auxiliary device actuation

    OpenAIRE

    F. Bucchi; Forte, P; F. Frendo; R. Squarcini

    2013-01-01

    In this paper the results of a project funded by Regione Toscana aimed at reducing the power absorption of auxiliary devices in vehicles are presented. In particular the design, testing and application of a magnetorheological clutch (MR) is proposed, aimed at disengaging the vacuum pump, which draws in air from the power-brake booster chamber, in order to reduce the device power absorption. Several clutch preliminary studies done to choose the clutch geometry and the magnetic field supply are...

  17. Direct FuelCell/Turbine Power Plant

    Energy Technology Data Exchange (ETDEWEB)

    Hossein Ghezel-Ayagh

    2008-09-30

    This report summarizes the progress made in development of Direct FuelCell/Turbine (DFC/T{reg_sign}) power plants for generation of clean power at very high efficiencies. The DFC/T system employs an indirectly heated Turbine Generator to supplement fuel cell generated power. The concept extends the high efficiency of the fuel cell by utilizing the fuel cell's byproduct heat in a Brayton cycle. Features of the DFC/T system include: electrical efficiencies of up to 75% on natural gas, minimal emissions, reduced carbon dioxide release to the environment, simplicity in design, direct reforming internal to the fuel cell, and potential cost competitiveness with existing combined cycle power plants. Proof-of-concept tests using a sub-MW-class DFC/T power plant at FuelCell Energy's (FCE) Danbury facility were conducted to validate the feasibility of the concept and to measure its potential for electric power production. A 400 kW-class power plant test facility was designed and retrofitted to conduct the tests. The initial series of tests involved integration of a full-size (250 kW) Direct FuelCell stack with a 30 kW Capstone microturbine. The operational aspects of the hybrid system in relation to the integration of the microturbine with the fuel cell, process flow and thermal balances, and control strategies for power cycling of the system, were investigated. A subsequent series of tests included operation of the sub-MW Direct FuelCell/Turbine power plant with a Capstone C60 microturbine. The C60 microturbine extended the range of operation of the hybrid power plant to higher current densities (higher power) than achieved in initial tests using the 30kW microturbine. The proof-of-concept test results confirmed the stability and controllability of operating a fullsize (250 kW) fuel cell stack in combination with a microturbine. Thermal management of the system was confirmed and power plant operation, using the microturbine as the only source of fresh air supply

  18. 核电厂辅助给水系统控制方案设计研究%Study on Control System of Auxiliary Feedwater System of Nuclear Power Plant

    Institute of Scientific and Technical Information of China (English)

    鲁超

    2015-01-01

    Auxiliary water supply system is an important system in the design of safety facilities of nuclear power station. The common cause fault of software and the power plant station blackout are two key factors for control system of ASG. So in the design of the control system, in order to deal with the two failure factors, the control strategy of diversity and emergency power supply are respectively adopted. Through analysis diversity control strategy is an effect method to prevent the failure of the safety functions resulting from software common cause failure which meets single failure criterion. In the case of station blackout, it is necessary to provide emergency power supply for control system of the starting ASG, and ensure the system safety functions workable.%辅助给水系统(ASG)是核电厂专设安全设施中重要的系统。对于实现对ASG功能控制的安全级系统,软件共因故障和全厂失电是导致控制失效的两个关键因素。因此,在进行控制系统设计时,为应对这两大失效因素,分别采用了多样性和增加应急电源的控制策略。通过分析,采用多样性控制策略可以有效地防止软件共因故障导致安全功能丧失的风险,保证系统满足单一故障的要求。同时在全厂断电的情况下,增加应急供电电源,对启动ASG功能的控制系统进行紧急供电,保证系统安全功能可执行。

  19. 45 CFR 707.10 - Auxiliary aids.

    Science.gov (United States)

    2010-10-01

    ... 45 Public Welfare 3 2010-10-01 2010-10-01 false Auxiliary aids. 707.10 Section 707.10 Public Welfare Regulations Relating to Public Welfare (Continued) COMMISSION ON CIVIL RIGHTS ENFORCEMENT OF... § 707.10 Auxiliary aids. (a) The Agency shall furnish appropriate auxiliary aids where necessary...

  20. 7 CFR 15b.37 - Auxiliary aids.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 1 2010-01-01 2010-01-01 false Auxiliary aids. 15b.37 Section 15b.37 Agriculture... ACTIVITIES RECEIVING FEDERAL FINANCIAL ASSISTANCE Other Aid, Benefits, or Services § 15b.37 Auxiliary aids... appropriate auxiliary aids to persons with impaired sensory, manual, or speaking skills, where necessary...

  1. Solid oxide fuel cell power system development

    Energy Technology Data Exchange (ETDEWEB)

    Kerr, Rick [Delphi Automotive Systems, LLC., Troy, MI (United States); Wall, Mark [Independent Energy Partners Technology, LLC., Parker, CO (United States); Sullivan, Neal [Colorado School of Mines, Golden, CO (United States)

    2015-06-26

    This report summarizes the progress made during this contractual period in achieving the goal of developing the solid oxide fuel cell (SOFC) cell and stack technology to be suitable for use in highly-efficient, economically-competitive, commercially deployed electrical power systems. Progress was made in further understanding cell and stack degradation mechanisms in order to increase stack reliability toward achieving a 4+ year lifetime, in cost reduction developments to meet the SECA stack cost target of $175/kW (in 2007 dollars), and in operating the SOFC technology in a multi-stack system in a real-world environment to understand the requirements for reliably designing and operating a large, stationary power system.

  2. Performance analysis of a Passive Auxiliary Feedwater System in APR+

    International Nuclear Information System (INIS)

    The Advanced Power Reactor Plus (APR+), which is a GEN III+ reactor based on the APR1400, is being developed in Korea. In order to enhance the safety of the APR+, a passive auxiliary feedwater system (PAFS) has been adopted in the APR+. The PAFS replaces the conventional active auxiliary feedwater system (AFWS) by introducing a natural driving force mechanism while maintaining the system function of cooling the primary side and removing the decay heat. The purpose of this paper is to evaluate the performance of the PAFS under design basis events using best-estimated thermalhydraulic codes

  3. 田阳县那坡镇宝美村龙达屯水利配套工程隧洞设计%The Tunnel Design of Water & Power Auxiliary Project in Longda Village of Baomei Hamlet in Napo Town of Tianyang County

    Institute of Scientific and Technical Information of China (English)

    钟顺钠

    2013-01-01

    The paper introduces the tunnel condition of water&power auxiliary project in Longda village of Baomei hamlet in Napo town of Tianyang county, and explains the design description of the drainage tunnel.%  文章介绍了田阳县那坡镇宝美村龙达屯水利配套工程隧洞概况,并对其排涝隧洞进行设计说明。

  4. Intelligent Power Management of hybrid Wind/ Fuel Cell/ Energy Storage Power Generation System

    OpenAIRE

    A. Hajizadeh; Hassanzadeh, F.

    2013-01-01

    This paper presents an intelligent power management strategy for hybrid wind/ fuel cell/ energy storage power generation system. The dynamic models of wind turbine, fuel cell and energy storage have been used for simulation of hybrid power system. In order to design power flow control strategy, a fuzzy logic control has been implemented to manage the power between power sources. The optimal operation of the hybrid power system is a main goal of designing power management strategy. The hybrid ...

  5. Radio frequency auxiliary heating systems design in ITER

    International Nuclear Information System (INIS)

    A combination of radio frequency (RF) auxiliary heating systems will provide at least one half of the required 100 MW of auxiliary power in ITER. Five of the 20 equatorial ports are assigned to RF heating systems. Recent work has focused on developing an integrated equatorial port-plug design concept for all of the RF auxiliary heating systems as well as other equatorial port systems such as diagnostics. Common features of the design approach include the use of identical interfaces to services such as cooling water, vacuum, mechanical connection to the vessel, and maintenance. Based on the integrated port concept, a high level of design integration has been achieved for the RF heating systems. Implementation of the integrated design concept has been accomplished without significantly affecting the individual system performance and with limited impact on the torus layout. (author)

  6. The Marginalized Auxiliary Particle Filter

    OpenAIRE

    Fritsche, Carsten; Schön, Thomas; Klein, Anja

    2010-01-01

    In this paper we are concerned with nonlinear systems subject to a conditionally linear, Gaussian sub-structure. This structure is often exploited in high-dimensional state estimation problems using the marginalized (aka Rao-Blackwellized) particle filter. The main contribution in the present work is to show how an efficient filter can be derived by exploiting this structure within the auxiliary particle filter. Based on a multisensor aircraft tracking example, the superior performance of the...

  7. Fuel cells for electric power generation

    International Nuclear Information System (INIS)

    After having first briefly illustrated the basic design, construction and operating principles of fuel cells, this paper assesses the progress that has been achieved to date in the development of the phosphoric acid (PAFC), molten carbonate (MCFC) and solid oxide (SOFC) fuel cells. Special attention is given to the design, performance and cost characteristics of the phosphoric acid fuel cells. For example, the paper cites the IFC/Toshiba 4.8 and 11.0 MW models, which have attained efficiencies of 37.5 and 41.0% respectively, and points out that these fuel cells, with efficiencies comparable to those of conventional poly-fuelled and combined cycle power plants, offer the advantages of compact size and better environmental compatibility with respect to the latter. However, fuel cells cannot yet compete with the lower per kWh costs of fossil fuel power plants. The paper concludes with an assessment of Italian fuel cell commercialization efforts, especially those centered around the use of methane fuelled PAFC's, and reviews the status of coordinated international research programs involving Japan, the USA and Italy

  8. Fuel cell power trains for road traffic

    Science.gov (United States)

    Höhlein, Bernd; Biedermann, Peter; Grube, Thomas; Menzer, Reinhard

    Legal regulations, especially the low emission vehicle (LEV) laws in California, are the driving forces for more intensive technological developments with respect to a global automobile market. In the future, high efficient vehicles at very low emission levels will include low temperature fuel cell systems (e.g., polymer electrolyte fuel cell (PEFC)) as units of hydrogen-, methanol- or gasoline-based electric power trains. In the case of methanol or gasoline/diesel, hydrogen has to be produced on-board using heated steam or partial oxidation reformers as well as catalytic burners and gas cleaning units. Methanol could also be used for direct electricity generation inside the fuel cell (direct methanol fuel cell (DMFC)). The development potentials and the results achieved so far for these concepts differ extremely. Based on the experience gained so far, the goals for the next few years include cost and weight reductions as well as optimizations in terms of the energy management of power trains with PEFC systems. At the same time, questions of fuel specification, fuel cycle management, materials balances and environmental assessment will have to be discussed more intensively. On the basis of process engineering analyses for net electricity generation in PEFC-powered power trains as well as on assumptions for both electric power trains and vehicle configurations, overall balances have been carried out. They will lead not only to specific energy demand data and specific emission levels (CO 2, CO, VOC, NO x) for the vehicle but will also present data of its full fuel cycle (FFC) in comparison to those of FFCs including internal combustion engines (ICE) after the year 2005. Depending on the development status (today or in 2010) and the FFC benchmark results, the advantages of balances results of FFC with PEFC vehicles are small in terms of specific energy demand and CO 2 emissions, but very high with respect to local emission levels.

  9. Fuel processor for fuel cell power system

    Science.gov (United States)

    Vanderborgh, Nicholas E.; Springer, Thomas E.; Huff, James R.

    1987-01-01

    A catalytic organic fuel processing apparatus, which can be used in a fuel cell power system, contains within a housing a catalyst chamber, a variable speed fan, and a combustion chamber. Vaporized organic fuel is circulated by the fan past the combustion chamber with which it is in indirect heat exchange relationship. The heated vaporized organic fuel enters a catalyst bed where it is converted into a desired product such as hydrogen needed to power the fuel cell. During periods of high demand, air is injected upstream of the combustion chamber and organic fuel injection means to burn with some of the organic fuel on the outside of the combustion chamber, and thus be in direct heat exchange relation with the organic fuel going into the catalyst bed.

  10. Fuel-cell based power generating system having power conditioning apparatus

    Science.gov (United States)

    Mazumder, Sudip K.; Pradhan, Sanjaya K.

    2010-10-05

    A power conditioner includes power converters for supplying power to a load, a set of selection switches corresponding to the power converters for selectively connecting the fuel-cell stack to the power converters, and another set of selection switches corresponding to the power converters for selectively connecting the battery to the power converters. The power conveners output combined power that substantially optimally meets a present demand of the load.

  11. Dynamic analysis of reactor auxiliary buildings

    International Nuclear Information System (INIS)

    A review of structural methods of generalized use in the dynamic analysis of Auxiliary Buildings and similar structures of Nuclear Power Plants is presented. Emphasis is placed on the structural response to blast and seismic loading studied from a global view point. Alternative models for the representation of both element and global stiffnesses are discussed. The assumption of rigid floor behaviour for lateral force excitation is studied. Advantages of using multi-stick models are referred and illustrated. The occurrence of torsional motions on the response is examined. The study evidences the importance of the low aspect ratio of these structures and shows its influence on parameters currently used in design of conventional buildings. (Author)

  12. 湿性脂肪干细胞辅助自体颗粒脂肪移植五年临床回顾总结%The five-year review of autologous fat transplantation with stem cell auxiliary

    Institute of Scientific and Technical Information of China (English)

    刘乃军; 王艳

    2013-01-01

    Objective Retrospective summary of clinical experience of wet autologous fat particles grafting with the stromal vascular cells and adipose stem cell-assisted,autologous fat transplantation withwith fat stem cell auxiliary during January 2008~April2013.Methods In 549 cases,532 were completed by one stage of filling injection.In the other 17 cases,the second procedure had been done due to the bad fat survival.Almost of the cases got significantly improvements and achieved desired clinical effect.In 2 cases minor complications happened.Results Conclusion Follow-up of 1~5,this kind of fat autologous transplantation can improve the survival rate of transplanted fat.Conclusion Autologous fat transplantation with with fat stem cell auxiliary can significantly improve the survival rate of transplanted fat cells and get good long-term effect.%目的:回顾总结2008 ~ 2013年笔者行湿性脂肪干细胞辅助自体颗粒脂肪注射填充移植术五年的临床经验.方法:549例均采用湿性脂肪干细胞辅助自体颗粒脂肪移植术,单次注射填充移植完成532例(96.91%),17例(3.09%)脂肪存活率较低(30% ~ 40%)需二次注射填充移植完成.结果:本组仅2例(0.36%)出现轻微并发症,成活率和远期效果明显提高,取得预期临床效果.结论:随访1~5,采用规范的湿性肿胀技术和注射器吸脂法抽吸颗粒脂肪及湿性新鲜原代血管基质细胞和脂肪干细胞辅助自体颗粒脂肪移植注射填充移植技术效果明显持久,遵循其正确的临床操作原则和技术指南及标准操作流程,能明显提高移植脂肪成活率和良好远期效果,是一种切实、可行、有效的临床方法.

  13. Intelligent Power Management of hybrid Wind/ Fuel Cell/ Energy Storage Power Generation System

    Directory of Open Access Journals (Sweden)

    A. Hajizadeh

    2013-12-01

    Full Text Available This paper presents an intelligent power management strategy for hybrid wind/ fuel cell/ energy storage power generation system. The dynamic models of wind turbine, fuel cell and energy storage have been used for simulation of hybrid power system. In order to design power flow control strategy, a fuzzy logic control has been implemented to manage the power between power sources. The optimal operation of the hybrid power system is a main goal of designing power management strategy. The hybrid power system is simulated in MATLAB/ SIMIULINK environment and different operating conditions have been considered to evaluate the response of power management strategy.

  14. Neoclassical offset toroidal velocity and auxiliary ion heating in tokamaks

    Science.gov (United States)

    Lazzaro, E.

    2016-05-01

    In conditions of ideal axisymmetry, for a magnetized plasma in a generic bounded domain, necessarily toroidal, the uniform absorption of external energy (e.g., RF or any isotropic auxiliary heating) cannot give rise to net forces or torques. Experimental evidence on contemporary tokamaks shows that the near central absorption of RF heating power (ICH and ECH) and current drive in presence of MHD activity drives a bulk plasma rotation in the co- I p direction, opposite to the initial one. Also the appearance of classical or neoclassical tearing modes provides a nonlinear magnetic braking that tends to clamp the rotation profile at the q-rational surfaces. The physical origin of the torque associated with P RF absorption could be due the effects of asymmetry in the equilibrium configuration or in power deposition, but here we point out also an effect of the response of the so-called neoclassical offset velocity to the power dependent heat flow increment. The neoclassical toroidal viscosity due to internal magnetic kink or tearing modes tends to relax the plasma rotation to this asymptotic speed, which in absence of auxiliary heating is of the order of the ion diamagnetic velocity. It can be shown by kinetic and fluid calculations, that the absorption of auxiliary power by ions modifies this offset proportionally to the injected power thereby forcing the plasma rotation in a direction opposite to the initial, to large values. The problem is discussed in the frame of the theoretical models of neoclassical toroidal viscosity.

  15. Solar-auxiliary Coal-fired Power Generation System Thermal Economic Analysis%太阳能辅助燃煤发电系统经济性分析

    Institute of Scientific and Technical Information of China (English)

    葛晓霞; 邵娜; 邵成; 钱晨; 姜晨峰

    2015-01-01

    介绍了太阳能辅助锅炉受热面替代部分省煤器作用和太阳能辅助给水回热加热的两种发电系统。应用等效热降法对这两种太阳能辅助燃煤发电集成方案的热经济指标进行了计算与比较,选择了太阳能辅助给水回热加热为优化的集成方案。对槽式集热器的换热效率,光热电转换效率及投资节煤比3个技术经济性相关指标进行研究,在太阳能辅助给水回热加热的方案中,通过综合比较利用太阳能产生的汽替换各级抽汽的计算结果后,得出了替换第六级抽汽最为合理的结论。%Two power generation systems were introduced about solar assisted part replace of boiler economizer heating surface effects and the solar-assisted heating feed water regenerator .It was calculated and compared these two types of solar assisted heat economic indicators coal-fired integrated solutions by using of Equivalent Heat Drop .It was selected a solar-assisted water heating for the optimization of regenerative integrated solution ., Three related indicators of technical and economic were studied On heat transfer efficiency of trough collector and the light thermoelectric conversion efficiency as well as investment in coal saving ratio .In the solar thermal heating auxiliary feedwater back scheme , By comprehensive comparison of the use of solar energy to produce steam to replace the calculation of results at all levels extraction .It was obtained the most reasonable conclusion of replacing sixth stage extraction .

  16. The dynamic responses of the soil-auxiliary buildings structure interaction system

    International Nuclear Information System (INIS)

    The dynamic responses of the soil-auxiliary buildings structure interaction system in the nuclear power plant are concerned. The main distinguished feature of this study is that the extreme un-symmetry of the auxiliary buildings and reactor containment are considered. A Synthetical mechanical model for study is established. Finally, the analysis of the dynamic response of the Qinshan Nuclear Power Plant structure is taken as a simple example of applying this method and the numerical results are given

  17. Perfects, resultatives and auxiliaries in early English

    OpenAIRE

    McFadden, Thomas; Alexiadou, Artemis

    2008-01-01

    In this paper, we will argue for a novel analysis of the auxiliary alternation in Early English, its development and subsequent loss which has broader consequences for the way that auxiliary selection is looked at cross-linguistically. We will present evidence that the choice of auxiliaries accompanying past participles in Early English differed in several significant respects from that in the familiar modern European languages. Specifically, while the construction with have became a full-fle...

  18. High efficiency fuel cell/advanced turbine power cycles

    Energy Technology Data Exchange (ETDEWEB)

    Morehead, H. [Westinghouse Electric Corp., Orlando, FL (United States)

    1995-10-19

    An outline of the Westinghouse high-efficiency fuel cell/advanced turbine power cycle is presented. The following topics are discussed: The Westinghouse SOFC pilot manufacturing facility, cell scale-up plan, pressure effects on SOFC power and efficiency, sureCell versus conventional gas turbine plants, sureCell product line for distributed power applications, 20 MW pressurized-SOFC/gas turbine power plant, 10 MW SOFC/CT power plant, sureCell plant concept design requirements, and Westinghouse SOFC market entry.

  19. Auxiliary bearing design and rotor dynamics analysis of blower fan for HTR-10

    International Nuclear Information System (INIS)

    The electromagnetic bearing instead of ordinary mechanical bearing was chosen to support the rotor in the blower fan system with helium of 10 MW high temperature gas-cooled test reactor (HTR-10), and the auxiliary bearing was applied in the HTR-10 as the backup protector. When the electromagnetic bearing doesn't work suddenly for the power broken, the auxiliary bearing is used to support the falling rotor with high rotating speed. The rotor system will be protected by the auxiliary bearing. The design of auxiliary bearing is the ultimate safeguard for the system. This rotor is vertically mounted to hold the blower fan. The rotor's length is about 1.5 m, its weight is about 240 kg and the rotating speed is about 5400 r/min. Auxiliary bearing design and rotor dynamics analysis are very important for the design of blower fan to make success. The research status of the auxiliary bearing was summarized in the paper. A sort of auxiliary bearing scheme was proposed. MSC.Marc was selected to analyze the vibration mode and the natural frequency of the rotor. The scheme design of auxiliary bearing and analysis result of rotor dynamics offer the important theoretical base for the protector design and control system of electromagnetic bearing of the blower fan. (authors)

  20. Auxiliary feedwater system aging study

    International Nuclear Information System (INIS)

    This report documents the results of a Phase I follow-on study of the Auxiliary Feedwater (AFW) System that has been conducted for the US Regulatory Commission's Nuclear Plant Aging research Program. The Phase I study found a number of significant AFW System functions that are not being adequately tested by conventional test methods and some that are actually being degraded by conventional testing. Thus, it was decided that this follow-on study would focus on these testing omissions nd equipment degradation. The deficiencies in current monitoring and operating practice are categorized and evaluated. Areas of component degradation caused by current practice are discussed. Recommendations are made for improved diagnostic methods and test procedures

  1. 福清核电1、2号机组增大应急给水箱容积安全分析%Safety Analysis on the Volume Increase of Auxiliary Water Tank for Number One and Two Units of Fuqing Nuclear Power Plant

    Institute of Scientific and Technical Information of China (English)

    佟立丽; 邵舸; 顾健; 薛峻峰; 彭建平; 王志强

    2013-01-01

    When main feed water system or start-up feed water system is unavailable, auxiliary feed water system, as Engineered Safety Facility (ESF), provides water for Steam Generators (SG) to remove the stored and decay heat from the reactor core. In order to improve the safety of Nuclear Power Plants (NPPs) and increase operational flexibility, the water inventory of the auxiliary feed water tank is increased in the number one and two units of Fuqing NPP. The model of the NPP is built based on mechanical safety analytical code, and conservative assumptions are used in the calculation. Three typical accident sequences, such as loss of main feed water, loss of offsite power in category Ⅱ accident, and main feed water line break in category IV, are selected to analyze whether or not the inventory in auxiliary water tank after improvement satisfies the relevant requirements in RCC-R The results show that auxiliary water inventory of 713m3 is needed for loss of main feed water accident, auxiliary water inventory of 723m3 is needed for loss of offsite power accident, and auxiliary water inventory of 799m3 is needed for main feed water line break accident. The inventory in auxiliary water tank after improvement satisfies the requirements for category Ⅱ and Ⅳ accidents. The safety of NPP is improved due to the inventory redundancy and a time window is also provided for the operators to perform related accident procedures.%辅助给水系统(ASG)作为专设安全设施在主给水或启动给水不可用时向蒸汽发生器供水,以导出堆芯余热.为了提高电厂安全性,增加运行灵活性,福清核电1、2号机组对应急给水箱的有效容积进行了增加.本文采用机理性安全分析程序,建立核电厂分析模型,在计算过程中采用保守假设条件,选取Ⅱ类工况下正常给水丧失事故,厂外电丧失事故,Ⅳ类工况下主给水管道破裂事故3条典型事故序列,分析改进后的应急给水箱容量是否满足压水

  2. 47 CFR 73.1675 - Auxiliary antennas.

    Science.gov (United States)

    2010-10-01

    ... Class A TV licensees may request a decrease from the authorized facility's ERP in the license application. An FM, TV or Class A TV licensee may also increase the ERP of the auxiliary facility in a license... licensed main facility as an auxiliary facility with an ERP less than or equal to the ERP specified on...

  3. Load-following mode control of a standalone renewable/fuel cell hybrid power source

    International Nuclear Information System (INIS)

    Highlights: • A FC hybrid power source (HPS) fed by renewable energy sources (RESs) is proposed. • The fuel cell (FC) operates as a backup to RESs based on the load-following strategy. • The energy storage device (ESS) will operate in charge-sustaining mode during a load cycle. • The ESS optimal design considers the peaks of RESs power and the imposed SOC window. • The FC/RES/ESS HPS is ideal to be used for standalone plug-in charge station. - Abstract: A hybrid power source (HPS), fed by renewable energy sources (RESs) and fuel cell (FC) sources, with an energy storage device (ESS) to be suitable for distributed generation (DG) applications, is proposed herein. The RESs could be a combination of photovoltaic (PV) panels and wind turbines (WT) based on common DC-bus, which are used as the primary DC source. The FC operates as a backup, feeding only the insufficiency power from the RESs based on the load-following strategy. The battery/ultracapacitor hybrid ESS operates as an auxiliary source for supplying the power deficit based on dynamic power balance strategy (the transient power – mainly via the ultracapacitors stack, and the steady-state power – mainly via the FC and batteries stack). If the FC stack is designed and operates based on average load-following strategy, then the ESS will operate in charge-sustaining mode during a load cycle. This feature permits to optimize the batteries stack capacity and extend its life time as well. The ultracapacitors stack can be designed considering the peaks of RESs power on DC-bus and the imposed window for its state-of-charge (SOC). This FC/RES/ESS HPS is ideal to be used for standalone plug-in charge station (PCS) or as DG system grid connected. In the last case, which is not analyzed here, the energy management unit (EMU) that communicates with smart grid will establish the moments to match the HPS power demand with grid supply availability, stabilizing the grid. Using load and RES power profiles that have

  4. Novel power electronic interface for grid-connected fuel cell power generation system

    International Nuclear Information System (INIS)

    Highlights: • A fuel cell power generation system was composed of a DC–DC power converter and a DC–AC inverter. • A voltage doubler based topology was adopted to configure the DC–DC power converter. • A dual buck power converter and a full-bridge power converter were applied to the DC–AC inverter. • The DC–AC inverter outputs a five-level voltage. • The DC–AC inverter performs the functions of DC–AC power conversion and active power filter. - Abstract: A novel power electronic interface for the grid-connected fuel cell power generation system is proposed in this paper. This power electronic interface is composed of a DC–DC power converter and a DC–AC inverter. A voltage doubler based topology is adopted to configure the DC–DC power converter to perform high step-up gain for boosting the output voltage of the fuel cell to a higher voltage. Moreover, the input current ripple of the fuel cell is suppressed by controlling the DC–DC power converter. The DC–AC inverter is configured by a dual buck power converter and a full-bridge power converter to generate a five-level AC output voltage. The DC–AC inverter can perform the functions of DC–AC power conversion and active power filtration. A 1.2 kW hardware prototype is developed to verify the performance of the proposed power electronic interface for the grid-connected fuel cell power generation system. The experimental results show that the proposed power electronic interface for the grid-connected fuel cell power generation system has the expected performance

  5. AC power generation from microbial fuel cells

    Science.gov (United States)

    Lobo, Fernanda Leite; Wang, Heming; Forrestal, Casey; Ren, Zhiyong Jason

    2015-11-01

    Microbial fuel cells (MFCs) directly convert biodegradable substrates to electricity and carry good potential for energy-positive wastewater treatment. However, the low and direct current (DC) output from MFC is not usable for general electronics except small sensors, yet commercial DC-AC converters or inverters used in solar systems cannot be directly applied to MFCs. This study presents a new DC-AC converter system for MFCs that can generate alternating voltage in any desired frequency. Results show that AC power can be easily achieved in three different frequencies tested (1, 10, 60 Hz), and no energy storage layer such as capacitors was needed. The DC-AC converter efficiency was higher than 95% when powered by either individual MFCs or simple MFC stacks. Total harmonic distortion (THD) was used to investigate the quality of the energy, and it showed that the energy could be directly usable for linear electronic loads. This study shows that through electrical conversion MFCs can be potentially used in household electronics for decentralized off-grid communities.

  6. Airport electric vehicle powered by fuel cell

    Energy Technology Data Exchange (ETDEWEB)

    Fontela, Pablo [Hybrid Systems Area of R and D Unit, BESEL S.A., Av del mediterraneo 22, Parque Tecnologico de Leganes, Leganes (Spain); Soria, Antonio [Area of Hybrid Systems Area of R and D Unit, BESEL S.A. (Spain); Mielgo, Javier; Sierra, Jose Francisco; de Blas, Juan [R and D Unit, BESEL S.A. (Spain); Gauchia, Lucia [Electric engineering Department, Carlos III University, Universidad Carlos III, Av. Universidad 30, Leganes (Spain); Martinez, Juan M. [Electric engineering Department, Carlos III University (Spain)

    2007-06-10

    Nowadays, new technologies and breakthroughs in the field of energy efficiency, alternative fuels and added-value electronics are leading to bigger, more sustainable and green thinking applications. Within the Automotive Industry, there is a clear declaration of commitment with the environment and natural resources. The presence of passenger vehicles of hybrid architecture, public transport powered by cleaner fuels, non-aggressive utility vehicles and an encouraging social awareness, are bringing to light a new scenario where conventional and advanced solutions will be in force. This paper presents the evolution of an airport cargo vehicle from battery-based propulsion to a hybrid power unit based on fuel cell, cutting edge batteries and hydrogen as a fuel. Some years back, IBERIA (Major Airline operating in Spain) decided to initiate the replacement of its diesel fleet for battery ones, aiming at a reduction in terms of contamination and noise in the surrounding environment. Unfortunately, due to extreme operating conditions in airports (ambient temperature, intensive use, dirtiness,..), batteries suffered a very severe degradation, which took its toll in terms of autonomy. This reduction in terms of autonomy together with the long battery recharge time made the intensive use of this fleet impractical in everyday demanding conditions. (author)

  7. Fuel Cells: Power System Option for Space Research

    Science.gov (United States)

    Shaneeth, M.; Mohanty, Surajeet

    2012-07-01

    Fuel Cells are direct energy conversion devices and, thereby, they deliver electrical energy at very high efficiency levels. Hydrogen and Oxygen gases are electrochemically processed, producing clean electric power with water as the only by product. A typical, Fuel Cell based power system involve a Electrochemical power converter, gas storage and management systems, thermal management systems and relevant control units. While there exists different types of Fuel cells, Proton Exchange Membrane (PEM) Fuel Cells are considered as the most suitable one for portable applications. Generally, Fuel Cells are considered as the primary power system option in space missions requiring high power ( > 5kW) and long durations and also where water is a consumable, such as manned missions. This is primarily due to the advantage that fuel cell based power systems offer, in terms of specific energy. Fuel cells have the potential to attain specific energy > 500Wh/kg, specific power >500W/kg, energy density > 400Whr/L and also power density > 200 W/L. This apart, a fuel cell system operate totally independent of sun light, whereas as battery based system is fully dependent on the same. This uniqueness provides added flexibility and capabilities to the missions and modularity for power system. High power requiring missions involving reusable launch vehicles, manned missions etc are expected to be richly benefited from this. Another potential application of Fuel Cell would be interplanetary exploration. Unpredictable and dusty atmospheres of heavenly bodies limits sun light significantly and there fuel cells of different types, eg, Bio-Fuel Cells, PEMFC, DMFCs would be able to work effectively. Manned or unmanned lunar out post would require continuous power even during extra long lunar nights and high power levels are expected. Regenerative Fuel Cells, a combination of Fuel Cells and Electrolysers, are identified as strong candidate. While application of Fuel Cells in high power

  8. Auxiliary Heating Systems for the Ignitor Project

    Science.gov (United States)

    Sassi, M.; Mantovani, S.; Coppi, B.

    2013-10-01

    Auxiliary plasma heating systems directed at extending the range of plasma regimes that can be accessed by Ohmic heating only are important components of the Ignitor machine. In order to affect the entire plasma column an appropriate ICRH systemhas been designed and components of it have been tested. The adoption of a 280 GHz system affecting, by ECRH, the outer edge of the plasma column has been proposed in order to influence temperature and density profiles in this important region. The ICRH system will operate over the range 80-120 MHz, consistent with magnetic fields in the range 9-13 T. The maximum delivered power goes from 8 MW (at 80 MHz) to 6 MW (at 120 MHz) distributed over 4 ports. A full size prototype of the VTL between the port flange and the antenna straps, with the external support and precise guiding system has been constructed. The innovative quick latching system located at the end of the coaxial cable has been successfully tested, providing perfect interference with the spring Be-Cu electrical contacts. Vacuum levels of 10-6, compatible with the limit of material degassing, and electrical tests up to 12 kV without discharges have been obtained. Special attention was given to the finishing of the inox surfaces, and to the TIG welds. U.S. DOE sponsored.

  9. Progress and prospects for phosphoric acid fuel cell power plants

    Energy Technology Data Exchange (ETDEWEB)

    Bonville, L.J.; Scheffler, G.W.; Smith, M.J. [International Fuel Cells Corp., South Windsor, CT (United States)

    1996-12-31

    International Fuel Cells (IFC) has developed the fuel cell power plant as a new, on-site power generation source. IFC`s commercial fuel cell product is the 200-kW PC25{trademark} power plant. To date over 100 PC25 units have been manufactured. Fleet operating time is in excess of one million hours. Individual units of the initial power plant model, the PC25 A, have operated for more than 30,000 hours. The first model {open_quotes}C{close_quotes} power plant has over 10,000 hours of operation. The manufacturing, application and operation of this power plant fleet has established a firm base for design and technology development in terms of a clear understanding of the requirements for power plant reliability and durability. This fleet provides the benchmark against which power plant improvements must be measured.

  10. Fuel cells multi-stack power architectures and experimental validation of 1 kW parallel twin stack PEFC generator based on high frequency magnetic coupling dedicated to on board power unit

    International Nuclear Information System (INIS)

    This paper presents a study of a polymer electrolyte fuel cell (PEFC) multi-stack generator and its power electronic interface dedicated to an on board vehicle power unit. A parallel electric architecture has been designed and tested. First, a dynamic model of the PEFC stack, valid for high frequencies and compatible with power converter interactions, has been developed. This model is used for simulations of the global fuel cell and power converter behaviors. Second, an inventory of generic multi-stack fuel cells architectures is presented in order to couple electrically the fuel cell stacks to an on board DC bus (in series, parallel, through magnetic coupling..). This state of the art is completed by an overview of several candidate power converter topologies for fuel cells. Then, among all the possible technical solutions, an original power converter architecture using a high frequency planar transformer is proposed, which allows parallel and series magnetic couplings of two fuel cell stacks. Then, the study focuses on a first step, which is the association of two PEFC stacks. Such a structure, having good efficiency, is well adapted for testing and operation of fuel cells in normal and degraded working modes, which correspond to real constraints on board a vehicle. Finally, experimental validations on a 2 x 500 W twin stack PEFC with power converter interface demonstrate the technological feasibility for the embarked multi-stack fuel cells generator. The 1 kW power level chosen for the experimentation is close to that of a small on board PEFC auxiliary power unit (APU)

  11. Generating Selected Color using RGB, Auxiliary Lights, and Simplex Search

    Directory of Open Access Journals (Sweden)

    Kim HyungTae

    2015-01-01

    Full Text Available A mixed light source generates various colors, with the potential to adjust intensities of multiple LEDs, which makes it possible to generate arbitrary colors. Currently, PCs and OSs provide color selection windows that can obtain the RGB or HSL color coordinates of a user’s selection. Mixed light sources are usually composed of LEDs in the primary colors, with LEDs in auxiliary colors such as white and yellow used in a few cases. When using auxiliary color LEDs, the number of LED inputs, the dimming levels, is larger than the number of elements in the color coordinate, which causes an under-determined problem. This study proposed how to determine the dimming levels of LEDs based on the selected color. Commercial LEDs have di_erent optical power values and impure color coordinates, even if they are RGB. Hence, the characteristics of the LEDs were described using a linear model derived from the tri-stimulus values (an XYZ color coordinate model and dimming levels. Color mixing models were derived for the arbitrary number of auxiliary color LEDs. The under-determined problem was solved using a simplex search method without an inverse matrix operation. The proposed method can be applied to a machine vision system and an RGBW light mixer for semiconductor inspection. The dimming levels, obtained using the proposed method were better than derived using other methods.

  12. 46 CFR 58.01-35 - Main propulsion auxiliary machinery.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Main propulsion auxiliary machinery. 58.01-35 Section 58... AUXILIARY MACHINERY AND RELATED SYSTEMS General Requirements § 58.01-35 Main propulsion auxiliary machinery. Auxiliary machinery vital to the main propulsion system must be provided in duplicate unless the...

  13. Applying fuel cell experience to sustainable power products

    Science.gov (United States)

    King, Joseph M.; O'Day, Michael J.

    Fuel cell power plants have demonstrated high efficiency, environmental friendliness, excellent transient response, and superior reliability and durability in spacecraft and stationary applications. Broader application of fuel cell technology promises significant contribution to sustainable global economic growth, but requires improvement to size, cost, fuel flexibility and operating flexibility. International Fuel Cells (IFC) is applying lessons learned from delivery of more than 425 fuel cell power plants and 3 million h of operation to the development of product technology which captures that promise. Key findings at the fuel cell power plant level include: (1) ancillary components account for more than 40% of the weight and nearly all unscheduled outages of hydrocarbon-fuelled power plants; a higher level of integration and simplification is required to achieve reasonable characteristics, (2) hydrocarbon fuel cell power plant components are highly interactive; the fuel processing approach and power plant operating pressure are major determinants of overall efficiency, and (3) achieving the durability required for heavy duty vehicles and stationary applications requires simultaneous satisfaction of electrochemical, materials and mechanical considerations in the design of the cell stack and other power plant components. Practical designs must minimize application specific equipment. Related lessons for stationary fuel cell power plants include: (1) within fuel specification limits, natural gas varies widely in heating value, minor constituents such as oxygen and nitrogen content and trace compounds such as the odorant; (2) city water quality varies widely; recovery of product water for process use avoids costly, complicated and site-specific water treatment systems, but water treatment is required to eliminate impurities and (3) the embedded protection functions for reliable operation of fuel cell power conditioners meet or exceed those required for connection to

  14. Fuel cells make gains in power generation market

    International Nuclear Information System (INIS)

    The ultra-low emission, highly efficient natural gas-fueled fuel cell system is beginning to penetrate the electric power generation market in the US and abroad as the fuel cell industry lowers product costs. And, even as the current market continues to grow, fuel cell companies are developing new technology with even higher levels of energy efficiency. The paper discusses fuel cell efficiency, business opportunities, work to reduce costs, and evolving fuel cell technology

  15. Process modeling of fuel cell vehicle power system

    Institute of Scientific and Technical Information of China (English)

    CHEN LiMing; LIN ZhaoJia; MA ZiFeng

    2009-01-01

    Constructed here is a mathematic model of PEM Fuel Cell Vehicle Power System which is composed of fuel supply model, fuel cell stack model and water-heat management model. The model was developed by Matiab/Simulink to evaluate how the major operating variables affect the output performances. Itshows that the constructed model can represent characteristics of the power system closely by comparing modeling results with experimental data, and it can be used in the study and design of fuel cell vehicle power system.

  16. Load cell for thermionic converter tests

    Science.gov (United States)

    Breitwieser, R.; Manista, E. J.

    1970-01-01

    Stable, low duty cycle transistorized emitter follower load cell controls and absorbs large currents at low voltages. The use of energy storage in capacitors reduces auxiliary power source requirements. Low duty cycle pulse mode of operation reduces the average power handling requirement of all components.

  17. The Power and the Promise of Cell Reprogramming: Personalized Autologous Body Organ and Cell Transplantation

    OpenAIRE

    Ana Belen Alvarez Palomo; Michaela Lucas; Dilley, Rodney J.; Samuel McLenachan; Fred Kuanfu Chen; Jordi Requena; Marti Farrera Sal; Andrew Lucas; Inaki Alvarez; Dolores Jaraquemada; Michael J. Edel

    2014-01-01

    Reprogramming somatic cells to induced pluripotent stem cells (iPSCs) or direct reprogramming to desired cell types are powerful and new in vitro methods for the study of human disease, cell replacement therapy, and drug development. Both methods to reprogram cells are unconstrained by the ethical and social questions raised by embryonic stem cells. iPSC technology promises to enable personalized autologous cell therapy and has the potential to revolutionize cell replacement therapy and rege...

  18. Dynamic simulation of a direct carbonate fuel cell power plant

    Energy Technology Data Exchange (ETDEWEB)

    Ernest, J.B. [Fluor Daniel, Inc., Irvine, CA (United States); Ghezel-Ayagh, H.; Kush, A.K. [Fuel Cell Engineering, Danbury, CT (United States)

    1996-12-31

    Fuel Cell Engineering Corporation (FCE) is commercializing a 2.85 MW Direct carbonate Fuel Cell (DFC) power plant. The commercialization sequence has already progressed through construction and operation of the first commercial-scale DFC power plant on a U.S. electric utility, the 2 MW Santa Clara Demonstration Project (SCDP), and the completion of the early phases of a Commercial Plant design. A 400 kW fuel cell stack Test Facility is being built at Energy Research Corporation (ERC), FCE`s parent company, which will be capable of testing commercial-sized fuel cell stacks in an integrated plant configuration. Fluor Daniel, Inc. provided engineering, procurement, and construction services for SCDP and has jointly developed the Commercial Plant design with FCE, focusing on the balance-of-plant (BOP) equipment outside of the fuel cell modules. This paper provides a brief orientation to the dynamic simulation of a fuel cell power plant and the benefits offered.

  19. Integrated Solid Oxide Fuel Cell Power System Characteristics Prediction

    Directory of Open Access Journals (Sweden)

    Marian GAICEANU

    2009-07-01

    Full Text Available The main objective of this paper is to deduce the specific characteristics of the CHP 100kWe Solid Oxide Fuel Cell (SOFC Power System from the steady state experimental data. From the experimental data, the authors have been developed and validated the steady state mathematical model. From the control room the steady state experimental data of the SOFC power conditioning are available and using the developed steady state mathematical model, the authors have been obtained the characteristic curves of the system performed by Siemens-Westinghouse Power Corporation. As a methodology the backward and forward power flow analysis has been employed. The backward power flow makes possible to obtain the SOFC power system operating point at different load levels, resulting as the load characteristic. By knowing the fuel cell output characteristic, the forward power flow analysis is used to predict the power system efficiency in different operating points, to choose the adequate control decision in order to obtain the high efficiency operation of the SOFC power system at different load levels. The CHP 100kWe power system is located at Gas Turbine Technologies Company (a Siemens Subsidiary, TurboCare brand in Turin, Italy. The work was carried out through the Energia da Ossidi Solidi (EOS Project. The SOFC stack delivers constant power permanently in order to supply the electric and thermal power both to the TurboCare Company and to the national grid.

  20. Builtin vs. auxiliary detection of extrapolation risk.

    Energy Technology Data Exchange (ETDEWEB)

    Munson, Miles Arthur; Kegelmeyer, W. Philip,

    2013-02-01

    A key assumption in supervised machine learning is that future data will be similar to historical data. This assumption is often false in real world applications, and as a result, prediction models often return predictions that are extrapolations. We compare four approaches to estimating extrapolation risk for machine learning predictions. Two builtin methods use information available from the classification model to decide if the model would be extrapolating for an input data point. The other two build auxiliary models to supplement the classification model and explicitly model extrapolation risk. Experiments with synthetic and real data sets show that the auxiliary models are more reliable risk detectors. To best safeguard against extrapolating predictions, however, we recommend combining builtin and auxiliary diagnostics.

  1. MARS calculation of PAFS (passive auxiliary feedwater system) heat exchanger in APR+

    International Nuclear Information System (INIS)

    APR+ (Advanced Power Reactor Plus), the next generation nuclear power plant in Korea, adopts PAFS (Passive Auxiliary Feedwater System) as one of the advanced safety feature. To design the condensation heat exchanger in PAFS, the two-phase flow phenomena in horizontal U-tube and PCCT (Passive Condensate Cooling Tank) were investigated by MARS calculation. By benchmarking with NOKO experimental result, MARS code showed a reasonable capability to quantitatively predict the condensation in horizontal tube heat exchanger. And the design of PAFS heat exchanger was proved to sufficiently remove the decay heat by the condensation heat transfer without any active auxiliary feedwater system

  2. Evaluation of Effect of N2 Gas on the Cooling Capability of Passive Auxiliary Feedwater System

    International Nuclear Information System (INIS)

    Advanced Power Reactor Plus (APR+), a next generation nuclear power plant in Korea, adopts Passive Auxiliary Feedwater System (PAFS) to replace the conventional active auxiliary feedwater system. Because PAFS removes decay heat from the reactor core, it is required to verify the performance of PAFS in postulated accidents cases. In addition, an effect of non-condensable gas such as N2 gas on the heat removal capability of PAFS should be evaluated since the non-condensable gas may deteriorate a condensation heat transfer through the condensation heat exchanger in PAFS. In this study, MARS code is used to evaluate the effect of N2 gas

  3. MARS calculation of PAFS (passive auxiliary feedwater system) heat exchanger in APR+

    Energy Technology Data Exchange (ETDEWEB)

    Bae, Byoung Uhn; Yun, Byong Jo; Bae, Sung Won; Choi, Ki Yong; Song, Chul Hwa [KAERI, Daejeon (Korea, Republic of); Cheon, Jong [Korea Hydro and Nuclear Power Co., Daejeon (Korea, Republic of)

    2009-07-01

    APR+ (Advanced Power Reactor Plus), the next generation nuclear power plant in Korea, adopts PAFS (Passive Auxiliary Feedwater System) as one of the advanced safety feature. To design the condensation heat exchanger in PAFS, the two-phase flow phenomena in horizontal U-tube and PCCT (Passive Condensate Cooling Tank) were investigated by MARS calculation. By benchmarking with NOKO experimental result, MARS code showed a reasonable capability to quantitatively predict the condensation in horizontal tube heat exchanger. And the design of PAFS heat exchanger was proved to sufficiently remove the decay heat by the condensation heat transfer without any active auxiliary feedwater system.

  4. Nuclear reactors with auxiliary boiler circuit

    International Nuclear Information System (INIS)

    A gas-cooled nuclear reactor has a main circulatory system for the gaseous coolant incorporating one or more main energy converting units, such as gas turbines, and an auxiliary circulatory system for the gaseous coolant incorporating at least one steam generating boiler arranged to be heated by the coolant after its passage through the reactor core to provide steam for driving an auxiliary steam turbine, such an arrangement providing a simplified start-up procedure also providing emergency duties associated with long term heat removal on reactor shut down

  5. Synthesis on power electronics for large fuel cells: From power conditioning to potentiodynamic analysis technique

    International Nuclear Information System (INIS)

    Highlights: • Active load for fuel cell managing electrical drive constraints: frequency and current ripple can be adjusted independently. • Multi-port resonant soft-switched topology for power management of a thirty kilowatt segmented PEM fuel cell. • Splitting current control strategy for power segmented PEM fuel cell in case of a segment is under fault. • Reversible Buck topology for large fuel cell with control of the fuel cell potential linked to current density nonlinearity. - Abstract: The work addressed in this paper deals with a synthesis on power electronic converters used for fuel cells. The knowledge gap concerns conceptually different electronic converter architectures for PEM (Proton Exchange Membrane) fuel cells able to perform three types of functionalities: The first one is the capacity of emulating an active load representative of electrical drive constraints. In that case, frequency and fuel cell current ripple can be set independently to investigate the dynamic behavior of the fuel cell. The second one is power conditioning applied to large high power and segmented fuel cell systems (“Large” represents several tens of cells and multi-kilowatt stacks), which is a non trivial consideration regarding the topological choices to be made for improving efficiency, compactness and ensure operation under faulty condition. A multi-port resonant isolated boost topology is analyzed enabling soft switching over a large operating range for a thirty kilowatt segmented fuel cell. A splitting current control strategy in case of a segment is under fault is proposed. Each considered converter topologies meet specific constraints regarding fuel cell stack design and power level. The third functionality is the ability for the power electronics to perform analysis and diagnosis techniques, like the cyclic voltammetry on large PEM fuel cell assemblies. The latter technique is an uncommon process for large fuel cell stacks since it is rather performed on

  6. A Lemon Cell Battery for High-Power Applications

    Science.gov (United States)

    Muske, Kenneth R.; Nigh, Christopher W.; Weinstein, Randy D.

    2007-04-01

    This article discusses the development of a lemon cell battery for high-power applications. The target application is the power source of a dc electric motor for a model car constructed by first-year engineering students as part of their introductory course design project and competition. The battery is composed of a series of lemon juice cells made from UV vis cuvets that use a magnesium anode and copper cathode. Dilution of the lemon juice to reduce the rate of corrosion of the magnesium anode and the addition of table salt to reduce the internal resistance of the cell are examined. Although our specific interest is the use of this lemon cell battery to run an electric dc motor, high-power applications such as radios, portable cassette or CD players, and other battery-powered toys are equally appropriate for demonstration and laboratory purposes using this battery.

  7. Advanced Space Power Systems (ASPS): Regenerative Fuel Cells (RFC) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The objective of the regenerative fuel cell project element is to develop power and energy storage technologies that enable new capabilities for future human space...

  8. Modeling and Nonlinear Control of Electric Power Stage in Hybrid Electric Vehicle

    DEFF Research Database (Denmark)

    Tahri, A.; El Fadil, H.; Guerrero, Josep M.;

    2014-01-01

    This paper deals with the problem of modeling and controlling the electric power stage of hybrid electric vehicle. The controlled system consists of a fuel cell (FC) as a main source, a supercapacitor as an auxiliary source, two DC-DC power converters, an inverter and a traction induction motor...

  9. Fuel Cell Assisted PhotoVoltaic Power Systems

    OpenAIRE

    Tesfahunegn, Samson Gebre

    2012-01-01

    Distributed generation (DG) systems as local power sources have great potential to contribute toward energy sustainability, energy efficiency and supply reliability. This thesis deals with DGs that use solar as primary energy input, hydrogen energy storage and conversion technologies (fuel cells and water electrolyzers) as long term backup and energy storage batteries and supercapacitors as short term backup. Standalone power systems isolated from the grid such as those used to power remote a...

  10. Prospects for advanced coal-fuelled fuel cell power plants

    International Nuclear Information System (INIS)

    As part of ECN's in-house R and D programmes on clean energy conversion systems with high efficiencies and low emissions, system assessment studies have been carried out on coal gasification power plants integrated with high-temperature fuel cells (IGFC). The studies also included the potential to reduce CO2 emissions, and to find possible ways for CO2 extraction and sequestration. The development of this new type of clean coal technology for large-scale power generation is still far off. A significant market share is not envisaged before the year 2015. To assess the future market potential of coal-fuelled fuel cell power plants, the promise of this fuel cell technology was assessed against the performance and the development of current state-of-the-art large-scale power generation systems, namely the pulverized coal-fired power plants and the integrated coal gasification combined cycle (IGCC) power plants. With the anticipated progress in gas turbine and gas clean-up technology, coal-fuelled fuel cell power plants will have to face severe competition from advanced IGCC power plants, despite their higher efficiency. (orig.)

  11. Power overshoot in two-chambered microbial fuel cell (MFC).

    Science.gov (United States)

    Nien, Po-Chin; Lee, Chin-Yu; Ho, Kuo-Chuan; Adav, Sunil S; Liu, Lihong; Wang, Aijie; Ren, Nanqi; Lee, Duu-Jong

    2011-04-01

    A two-chamber microbial fuel cell was started using iron-reducing strains as inoculum and acetate as carbon sources. The tested microbial fuel cell had an open-circuit voltage of 0.67 V, and reached 1045 mA m(-2) and a power density of 486 mW m(-2) at 0.46 V before power overshoot occurred. Anodic reactions were identified as the rate-determining steps. Stirring the anolyte insignificantly increased cell performance, suggesting a minimal external mass transfer resistance from the anolyte to the anodic biofilm. Data regression analysis indicates that charge transfer resistance at the biofilm-anode junction was negligible. The order of magnitude estimation of electrical conductance indicates that electron transfer resistance had an insignificant effect on microbial fuel cell performance. Resistance in electrogens for substrate utilization is proposed to induce microbial fuel cell power overshoot. PMID:21295969

  12. Accelerating Acceptance of Fuel Cell Backup Power Systems - Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Petrecky, James; Ashley, Christopher

    2014-07-21

    Since 2001, Plug Power has installed more than 800 stationary fuel cell systems worldwide. Plug Power’s prime power systems have produced approximately 6.5 million kilowatt hours of electricity and have accumulated more than 2.5 million operating hours. Intermittent, or backup, power products have been deployed with telecommunications carriers and government and utility customers in North and South America, Europe, the United Kingdom, Japan and South Africa. Some of the largest material handling operations in North America are currently using the company’s motive power units in fuel cell-powered forklifts for their warehouses, distribution centers and manufacturing facilities. The low-temperature GenSys fuel cell system provides remote, off-grid and primary power where grid power is unreliable or nonexistent. Built reliable and designed rugged, low- temperature GenSys delivers continuous or backup power through even the most extreme conditions. Coupled with high-efficiency ratings, low-temperature GenSys reduces operating costs making it an economical solution for prime power requirements. Currently, field trials at telecommunication and industrial sites across the globe are proving the advantages of fuel cells—lower maintenance, fuel costs and emissions, as well as longer life—compared with traditional internal combustion engines.

  13. High power density yeast catalyzed microbial fuel cells

    Science.gov (United States)

    Ganguli, Rahul

    Microbial fuel cells leverage whole cell biocatalysis to convert the energy stored in energy-rich renewable biomolecules such as sugar, directly to electrical energy at high efficiencies. Advantages of the process include ambient temperature operation, operation in natural streams such as wastewater without the need to clean electrodes, minimal balance-of-plant requirements compared to conventional fuel cells, and environmentally friendly operation. These make the technology very attractive as portable power sources and waste-to-energy converters. The principal problem facing the technology is the low power densities compared to other conventional portable power sources such as batteries and traditional fuel cells. In this work we examined the yeast catalyzed microbial fuel cell and developed methods to increase the power density from such fuel cells. A combination of cyclic voltammetry and optical absorption measurements were used to establish significant adsorption of electron mediators by the microbes. Mediator adsorption was demonstrated to be an important limitation in achieving high power densities in yeast-catalyzed microbial fuel cells. Specifically, the power densities are low for the length of time mediator adsorption continues to occur. Once the mediator adsorption stops, the power densities increase. Rotating disk chronoamperometry was used to extract reaction rate information, and a simple kinetic expression was developed for the current observed in the anodic half-cell. Since the rate expression showed that the current was directly related to microbe concentration close to the electrode, methods to increase cell mass attached to the anode was investigated. Electrically biased electrodes were demonstrated to develop biofilm-like layers of the Baker's yeast with a high concentration of cells directly connected to the electrode. The increased cell mass did increase the power density 2 times compared to a non biofilm fuel cell, but the power density

  14. Curricular Guidelines for Dental Auxiliary Radiology.

    Science.gov (United States)

    Journal of Dental Education, 1981

    1981-01-01

    AADS curricular guidelines suggest objectives for these areas of dental auxiliary radiology: physical principles of X-radiation in dentistry, related radiobiological concepts, principles of radiologic health, radiographic technique, x-ray films and intensifying screens, factors contributing to film quality, darkroom, and normal variations in…

  15. Window-mounted auxiliary solar heater

    Science.gov (United States)

    Anthony, K. G.; Herndon, E. P.

    1977-01-01

    System uses hot-air collectors, no thermal storage, and fan with thermostat switches. At cost of heating efficiency, unit could be manufactured and sold at price allowing immediate entry to market as auxiliary heating system. Its simplicity allows homeowner installation, and maintenance is minimal.

  16. Power-cancellation of CW-complexes with few cells

    OpenAIRE

    Llerena, Irene

    1992-01-01

    In this paper, we use the fact that the rings of integer matrices have the power-substitution property in order to obtain a powercancellation property for homotopy types of CW-complexes with one cell in dimensions 0 and 4n and a finite number of cells in dimension 2n.

  17. Fuel cell and advanced turbine power cycle

    Energy Technology Data Exchange (ETDEWEB)

    White, D.J. [Solar Turbines, Inc., San Diego, CA (United States)

    1995-10-19

    Solar Turbines, Incorporated (Solar) has a vested interest in the integration of gas turbines and high temperature fuel cells and in particular, solid oxide fuel cells (SOFCs). Solar has identified a parallel path approach to the technology developments needed for future products. The primary approach is to move away from the simple cycle industrial machines of the past and develop as a first step more efficient recuperated engines. This move was prompted by the recognition that the simple cycle machines were rapidly approaching their efficiency limits. Improving the efficiency of simple cycle machines is and will become increasingly more costly. Each efficiency increment will be progressively more costly than the previous step.

  18. Power generation properties of Direct Flame Fuel Cell (DFFC)

    International Nuclear Information System (INIS)

    This paper investigated the effect of cell temperature and product species concentration induced by small-jet flame on the power generation performance of Direct Flame Fuel Cell (DFFC). The cell is placed above the small flame and heated product gas is impinged toward it and this system is the simplest and smallest unit of the power generation device to be developed. Equivalence ratio (φ) and the distance between the cell and the burner surface (d) are considered as main experimental parameters. It turns out that open circuit voltage (OCV) increases linearly with the increase of temperature in wide range of equivalence ratios. However, it increases drastically at which the equivalence ratio became small (φ ≤ 2.0) showing inner flame clearly. This result suggests that OCV depends on not only cell temperature but also the species concentration exposed to the cell. It is suggested that Nernst equation might work satisfactory to predict OCV of DFFC

  19. Smart Energy Management of Multiple Full Cell Powered Applications

    Energy Technology Data Exchange (ETDEWEB)

    Mohammad S. Alam

    2007-04-23

    In this research project the University of South Alabama research team has been investigating smart energy management and control of multiple fuel cell power sources when subjected to varying demands of electrical and thermal loads together with demands of hydrogen production. This research has focused on finding the optimal schedule of the multiple fuel cell power plants in terms of electric, thermal and hydrogen energy. The optimal schedule is expected to yield the lowest operating cost. Our team is also investigating the possibility of generating hydrogen using photoelectrochemical (PEC) solar cells through finding materials for efficient light harvesting photoanodes. The goal is to develop an efficient and cost effective PEC solar cell system for direct electrolysis of water. In addition, models for hydrogen production, purification, and storage will be developed. The results obtained and the data collected will be then used to develop a smart energy management algorithm whose function is to maximize energy conservation within a managed set of appliances, thereby lowering O/M costs of the Fuel Cell power plant (FCPP), and allowing more hydrogen generation opportunities. The Smart Energy Management and Control (SEMaC) software, developed earlier, controls electrical loads in an individual home to achieve load management objectives such that the total power consumption of a typical residential home remains below the available power generated from a fuel cell. In this project, the research team will leverage the SEMaC algorithm developed earlier to create a neighborhood level control system.

  20. Electrochemical power sources batteries, fuel cells, and supercapacitors

    CERN Document Server

    Bagotsky, Vladimir S; Volfkovich, Yurij M

    2015-01-01

    Electrochemical Power Sources (EPS) provides in a concise way theoperational features, major types, and applications of batteries,fuel cells, and supercapacitors Details the design, operational features, andapplications of batteries, fuel cells, and supercapacitors Covers improvements of existing EPSs and thedevelopment of new kinds of EPS as the results of intense R&Dwork Provides outlook for future trends in fuel cells andbatteries Covers the most typical battery types, fuel cells andsupercapacitors; such as zinc-carbon batteries, alkaline manganesedioxide batteries, mercury-zinc cells, lead

  1. Auxiliary-Arc Electrodes for MHD Systems

    International Nuclear Information System (INIS)

    The important role of electrode phenomena in the operation of magneto aerodynamic machines is well known. In particular, the voltage drops which occur in the boundary layer in the immediate neighbourhood of the electrode may reduce the output of the apparatus. These voltage drops are caused partly by the increased resistance presented by the boundary layer in the neighbourhood of the electrode when the latter is appreciably colder than the gas, and partly by the fact that the electrode is not at a temperature sufficient to be emissive. Auxiliary-arc electrodes that have been constructed and tested seem to provide a solution both of the cold boundary layer problem and of the cathode emissivity problem. For this purpose an arc is established between a refractory metal cathode placed behind and clear of the generator wall and an anode forming part of the wall. The arc column can be activated by a rotational movement under the effect of a magnetic field, which may be that of the machine itself. The mechanical arrangement of the electrodes is such that, with a weak flow of gas (argon for example), it is possible to maintain a protective atmosphere around the arc cathode, while the arc anode is strongly cooled by the wall. The gas flow also has the effect of forcing the arc column towards the stream, thus increasing the conductivity of the boundary layer. Furthermore, the arc column behaves as a virtual cathode, from which a sizeable electron current can be extracted. Electrodes constructed on this principle have been tested on gas streams composed of fuel-oil combustion products. By using them as cathodes it has been possible to extract a current of 5 A without the voltage drop between the electrode and the gas exceeding 10 V. Comparative tests have been carried out with cooled metal electrodes, in which case the voltage drop is of the order of 120 V. The arc electrodes tested have operated for several hours without any apparent damage. In spite of the energy which has

  2. Fuzzy Control of Polymer Fuel Cell for Attract Maximum Power

    Directory of Open Access Journals (Sweden)

    Zahra Nejati

    2014-01-01

    Full Text Available Polymer fuel cell is one of the most attractive of fuel cell from point of the design and operation and also in comparison with other types of fuel cell, for a weight and size, polymer fuel cell produces more power. But however, one of the problems to use of this system is its low efficiency .To overcome the low efficiency of the fuel cell polymer in this paper is tried to used from maximum power point tracking. According to the characteristic of the flow –power the fuel cell, which is a non-linear curve and has a maximum point and use of the fuzzy controller and the proper selection of input and output membership functions trying to the System always works at maximum power. For this purpose, a chopper is used between the fuel cell and the load and to adjust the duty cycle of the applied signal to it is applied the fuzzy-TSK type controller that Its inputs are stream slope and slope changes. The results show that this controller has a good performance and that is faster compared with the perturbation and observation method.

  3. Evaluation program for secondary spacecraft cells: Initial evaluation tests of Gulton Industries, Incorporated, 9.0 ampere-hour nickel-cadmium spacecraft cells with auxiliary electrodes for the small astronomy Satellite (SAS-C)

    Science.gov (United States)

    Harkness, J. D.

    1975-01-01

    An evaluation test program was conducted to insure that all cells put into the life cycle program are of high quality by the screening of cells found to have electrolyte leakage, internal shorts, low capacity, or inability of any cell to recover its open-circuit voltage above 1.150 volts during the internal short test. Tests and results are described.

  4. Single Glucose Biofuel Cells Implanted in Rats Power Electronic Devices

    Science.gov (United States)

    Zebda, A.; Cosnier, S.; Alcaraz, J.-P.; Holzinger, M.; Le Goff, A.; Gondran, C.; Boucher, F.; Giroud, F.; Gorgy, K.; Lamraoui, H.; Cinquin, P.

    2013-01-01

    We describe the first implanted glucose biofuel cell (GBFC) that is capable of generating sufficient power from a mammal's body fluids to act as the sole power source for electronic devices. This GBFC is based on carbon nanotube/enzyme electrodes, which utilize glucose oxidase for glucose oxidation and laccase for dioxygen reduction. The GBFC, implanted in the abdominal cavity of a rat, produces an average open-circuit voltage of 0.57 V. This implanted GBFC delivered a power output of 38.7 μW, which corresponded to a power density of 193.5 μW cm−2 and a volumetric power of 161 μW mL−1. We demonstrate that one single implanted enzymatic GBFC can power a light-emitting diode (LED), or a digital thermometer. In addition, no signs of rejection or inflammation were observed after 110 days implantation in the rat. PMID:23519113

  5. Auxiliary field formulation of supersymmetric nonlinear sigma models

    International Nuclear Information System (INIS)

    Two dimensional N=2 supersymmetric nonlinear sigma models on hermitian symmetric spaces are formulated in terms of the auxiliary superfields. If we eliminate auxiliary vector and chiral superfields, they give D- and F- term constraints to define the target manifolds. The integration over auxiliary vector superfields, which can be performed exactly, is equivalent to the elimination of the auxiliary fields by the use of the classical equations of motion. (author)

  6. Computer determination of event maps with application to auxiliary supply systems

    International Nuclear Information System (INIS)

    A method of evaluating the reliability of sequential operations in systems containing standby and alternate supply facilities is presented. The method is based upon the use of a digital computer for automatic development of event maps. The technique is illustrated by application to a nuclear power plant auxiliary supply system. (author)

  7. Soft switching DC/DC converter using controlled output rectifier with auxiliary circuit

    OpenAIRE

    Dudrik, Jaroslav; BODOR Marcel; TRIP Daniel Nistor

    2010-01-01

    Auxiliary circuit for DC/DC converter withcontrolled output rectifier is presented in this paper.Soft switching for power switches of the inverter isachieved by using controlled output rectifier and softswitching of the controlled rectifier by using losslessauxiliary circuit. The principle of converter operationis explained and analyzed and experimental results onthe laboratory model are presented.

  8. Opportunities and issues for hydrogen-powered PEM fuel cell stationary power systems

    Energy Technology Data Exchange (ETDEWEB)

    Richards, M. [Institute of Gas Technology, Des Plaines, IL (United States); Gyger, R. [Mosaic Energy, Marilleville, IN (United States)

    2000-05-01

    The future potential of the polymer electrolyte membrane (PEM) fuel cell for stationary power applications was reviewed in this power point presentation along with the potential market opportunities and issues. A company profile of the Institute of Gas Technology (IGT) and Mosaic Energy was also provided. IGT is a technology development organization involved in electrochemical technology, energy systems, combustion technology, bio-remediation technology and gas operations. Mosaic Energy is a joint venture company owned by IGT. Their goal is to commercial PEM fuel cell systems for both residential and commercial markets. Fuel cells could be used to provide electricity to buildings, communications power, industrial cogeneration, utility ancillary services, and portable and remote power applications. PEM fuel cells, however, will be limited to smaller applications such as building baseload power and uninterruptible power supply (UPS). A large number of hydrogen storage units would be needed for such purposes, creating an initial market for new storage technologies. It was also noted that the specific hydrogen opportunity is limited by supply and infrastructure cost. Hydrogen is more suitable for UPS markets but more refinement is still needed in hydrogen storage even in this domain. 2 tabs., 8 figs.

  9. Solar combisystems with forecast control to increase the solar fraction and lower the auxiliary energy cost

    DEFF Research Database (Denmark)

    Perers, Bengt; Furbo, Simon; Fan, Jianhua;

    2011-01-01

    Solar Combi systems still need quite a lot of auxiliary energy especially in small systems without seasonal storage possibilities. The control of the auxiliary energy input both in time and power is important to utilize as much as possible of the solar energy available from the collectors and also...... energy sources. It can be either direct electric heating elements or a heat pump upgrading ambient energy in the air, ground, solar collector or waste heat from the house. The paper describes system modeling and simulation results. Advanced laboratory experiments are also starting now with three...

  10. A portable power system using PEM fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Long, E. [Ball Aerospace and Technologies Corp., Boulder, CO (United States)

    1997-12-31

    Ball has developed a proof-of-concept, small, lightweight, portable power system. The power system uses a proton exchange membrane (PEM) fuel cell stack, stored hydrogen, and atmospheric oxygen as the oxidant to generate electrical power. Electronics monitor the system performance to control cooling air and oxidant flow, and automatically do corrective measures to maintain performance. With the controller monitoring the system health, the system can operate in an ambient environment from 0 C to +50 C. The paper describes system testing, including load testing, thermal and humidity testing, vibration and shock testing, field testing, destructive testing of high-pressure gas tanks, and test results on the fuel cell power system, metal hydride hydrogen storage, high-pressure hydrogen gas storage, and chemical hydride hydrogen storage.

  11. Thermionic Power Cell To Harness Heat Energies for Geothermal Applications

    Science.gov (United States)

    Manohara, Harish; Mojarradi, Mohammad; Greer, Harold F.

    2011-01-01

    A unit thermionic power cell (TPC) concept has been developed that converts natural heat found in high-temperature environments (460 to 700 C) into electrical power for in situ instruments and electronics. Thermionic emission of electrons occurs when an emitter filament is heated to gwhite hot h temperatures (>1,000 C) allowing electrons to overcome the potential barrier and emit into the vacuum. These electrons are then collected by an anode, and transported to the external circuit for energy storage.

  12. Thermoelectric cells cogeneration from biomass power plant: literature review

    OpenAIRE

    Bianchini, Augusto; Donini, Filippo; Pellegrini, Marco

    2015-01-01

    Thermoelectric cells convert directly heat into electricity but, due to the low conversion efficiency (up to 5%), most applications are in waste heat recovery. Another promising application is in biomass boiler. In this case, the installation of thermoelectric modules converts a biomass boiler into a cogeneration system, where the aim of the integration is not the electricity production for external power supply, but the realization of a stand-alone biomass power plant which could match the c...

  13. Modified Darboux transformations with foreign auxiliary equations

    International Nuclear Information System (INIS)

    We construct a new type of first-order Darboux transformations for the stationary Schroedinger equation. In contrast to the conventional case, our Darboux transformations support arbitrary (foreign) auxiliary equations. We show that among other applications, our formalism can be used to systematically construct Darboux transformations for Schroedinger equations with energy-dependent potentials, including a recent result (Lin et al., 2007) as a special case. -- Highlights: → We generalize the Darboux transformation for the Schroedinger equation. → By admitting arbitrary auxiliary functions, we provide a new tool for generating solutions. → As a special case we recover a recent result on energy-dependent potentials. → We extend the latter result to very general energy-dependence.

  14. An Intelligent Auxiliary Vacuum Brake System

    OpenAIRE

    Tong, Chia-Chang; Lin, Jhih-Yu; Li, Shih-Fan; Li, Jiun-Yi

    2009-01-01

    The purpose of this paper focuses on designing an intelligent, compact, reliable, and robust auxiliary vacuum brake system (VBS) with Kalman filter and self-diagnosis scheme. All of the circuit elements in the designed system are integrated into one programmable system-on-chip (PSoC) with entire computational algorithms implemented by software. In this system, three main goals are achieved: (a) Kalman filter and hysteresis controller algorithms are employed within PSoC chip by software to sur...

  15. Auxiliary facilities on nuclear ship 'MUTSU'

    International Nuclear Information System (INIS)

    The nuclear ship 'MUTSU' has been moored at SEKINEHAMA, MUTU City in AOMORI Prefecture and several tests and works are being carried out on the ship. The construction of the auxiliary facilities for these works on the ship was completed in safety in August 1988. After that the facilities have fulfilled their function. The outlines of design, fabrication and construction of the facilities are described in this paper. (author)

  16. New Massive Supergravity and Auxiliary Fields

    CERN Document Server

    Bergshoeff, Eric A; Parra, Lorena; Rosseel, Jan; Yin, Yihao; Zojer, Thomas

    2013-01-01

    We construct a supersymmetric formulation of linearized New Massive Gravity without introducing higher derivatives. Instead, we introduce supersymmetrically a set of bosonic and fermionic auxiliary fields which, upon elimination by their equations of motion, introduce fourth-order derivative terms for the metric and third-order derivative terms for the gravitino. Our construction requires an off-shell formulation of the three-dimensional supersymmetric massive Fierz--Pauli theory. We discuss the non-linear extension of our results.

  17. Auxiliary nRules of Quantum Mechanics

    OpenAIRE

    Mould, Richard A

    2005-01-01

    Standard quantum mechanics makes use of four auxiliary rules that allow the Schrodinger solutions to be related to laboratory experience, such as the Born rule that connects square modulus to probability. These rules (here called the sRules) lead to some unacceptable results. They do not allow the primary observer to be part of the system. They do not allow individual observations (as opposed to ensembles) to be part of the system. They make a fundamental distinction between microscopic and m...

  18. Auxiliary nRules of Quantum Mechanics

    CERN Document Server

    Mould, R A

    2005-01-01

    Standard quantum mechanics makes use of four auxiliary rules that allow the Schrodinger solutions to be related to laboratory experience, such as the Born rule that connects square modulus to probability. These rules (here called the sRules) lead to some unacceptable results. They do not allow the primary observer to be part of the system. They do not allow individual observations (as opposed to ensembles) to be part of the system. They make a fundamental distinction between microscopic and macroscopic things, and they are ambiguous in their description of secondary observers such as Schrodingers cat. The nRules are an alternative set of auxiliary rules that avoid the above difficulties. In this paper we look at a wide range of representative experiments showing that the nRules adequately relate the Schrodinger solutions to empirical experience. This suggests that the sRules should be abandoned in favor of the more satisfactory nRules, or a third auxiliary rule-set called the oRules. Keywords: brain states, c...

  19. Maximum power point tracking control of direct methanol fuel cells

    Science.gov (United States)

    Zhang, Mingbo; Yan, Ting; Gu, Jinguang

    2014-02-01

    The performance of a direct methanol fuel cell (DMFC) is closely related to its operating conditions, and there is a specific combination of operating conditions at which the DMFC produces maximum power. Working at the maximum power point (MPP) can lower the methanol crossover rate and ancillary power consumption, improving the global efficiency of the system. The fuzzy controller proposed in this paper provides a simple and robust way to keep the DMFC working at the MPP by adjusting the operating conditions followed by the variation of the driven load in real time. Simulation shows that the fuzzy control approach can yield satisfactory results.

  20. Single Glucose Biofuel Cells Implanted in Rats Power Electronic Devices

    OpenAIRE

    Zebda, A.; Cosnier, S.; J.-P. Alcaraz; Holzinger, M.; A. Le Goff; Gondran, C.; Boucher, F.; Giroud, F.; Gorgy, K.; Lamraoui, H.; Cinquin, P.

    2013-01-01

    We describe the first implanted glucose biofuel cell (GBFC) that is capable of generating sufficient power from a mammal's body fluids to act as the sole power source for electronic devices. This GBFC is based on carbon nanotube/enzyme electrodes, which utilize glucose oxidase for glucose oxidation and laccase for dioxygen reduction. The GBFC, implanted in the abdominal cavity of a rat, produces an average open-circuit voltage of 0.57 V. This implanted GBFC delivered a power output of 38.7 μW...

  1. Integrating fuel cell power systems into building physical plants

    Energy Technology Data Exchange (ETDEWEB)

    Carson, J. [KCI Technologies, Inc., Hunt Valley, MD (United States)

    1996-12-31

    This paper discusses the integration of fuel cell power plants and absorption chillers to cogenerate chilled water or hot water/steam for all weather air conditioning as one possible approach to building system applications. Absorption chillers utilize thermal energy in an absorption based cycle to chill water. It is feasible to use waste heat from fuel cells to provide hydronic heating and cooling. Performance regimes will vary as a function of the supply and quality of waste heat. Respective performance characteristics of fuel cells, absorption chillers and air conditioning systems will define relationships between thermal and electrical load capacities for the combined systems. Specifically, this paper develops thermodynamic relationships between bulk electrical power and cooling/heating capacities for combined fuel cell and absorption chiller system in building applications.

  2. Low power ultrasound inhibits cell proliferation and invasion of human cancer cells in vitro

    Directory of Open Access Journals (Sweden)

    Etienne Mfoumou

    2012-01-01

    Full Text Available Background: Applications of ultrasound in medicine for therapeutic purposes have been accepted, and they have several beneficial uses for many years. However, the outcome of low power ultrasound waves on cell proliferation, especially cell cycle progression and invasion as well as their associated genes on human breast and cervical cancer cells has not been investigated yet. Therefore, we examined the effect of low power ultrasound on BT20, BT20-E6/E7 and HeLa cell lines. Materials and Methods: BT20, BT20-E6/E7 and HeLa cell lines were used in this study. On the other hand, cell proliferation, cell cycle, and invasion assays were applied to study the effect of low ultrasound irradiation on these cell lines. Meanwhile, western blot was performed to study the expression patterns of some selected genes associated with this effect. Results: We found that low power ultrasound inhibits cell proliferation and provokes G0-G1 cell cycle arrest and reduction of S as well as an increase in the G2-M phase of HeLa cells in comparison with the untreated cells. This is accompanied by a down-regulation of Cdk-6 (cyclin dependent kinase which is a major control switch for the cell cycle. Moreover, low power ultrasound inhibits cell invasion and consequently down-regulates the expression of Id-1, caveolin, and EGF-R which are widely considered as main regulators of cell invasion and metastasis of human cancer. Conclusion: These results suggest that application of low power ultrasound on human breast and cervical cancer could be an effective method to reduce cell proliferation and invasion of these cancers.

  3. CMOS Low Power Cell Library for Digital Design

    Directory of Open Access Journals (Sweden)

    Kanika Kaur

    2013-06-01

    Full Text Available Historically, VLSI designers have focused on increasing the speed and reducing the area of digital systems. However, the evolution of portable systems and advanced Deep Sub-Micron fabrication technologies have brought power dissipation as another critical design factor. Low power design reduces cooling cost and increases reliability especially for high density systems. Moreover, it reduces the weight and size of portable devices. The power dissipation in CMOS circuits consists of static and dynamic components. Since dynamic power is proportional to V2 dd and static power is proportional to Vdd, lowering the supply voltage and device dimensions, the transistor threshold voltage also has to be scaled down to achieve the required performance. In case of static power, the power is consumed during the steady state condition i.e when there are no input/output transitions. Static power has two sources: DC power and Leakage power. Consecutively to facilitate voltage scaling without disturbing the performance, threshold voltage has to be minimized. Furthermore it leads to better noise margins and helps to avoid the hot carrier effects in short channel devices. In this paper we have been proposed the new CMOS library for the complex digital design using scaling the supply voltage and device dimensions and also suggest the methods to control the leakage current to obtain the minimum power dissipation at optimum value of supply voltage and transistor threshold. In this paper CMOS Cell library has been implemented using TSMC (0.18um and TSMC (90nm technology using HEP2 tool of IC designing from Mentor Graphics for various analysis and simulations.

  4. FUEL CELL OPERATION ON LANDFILL GAS AT PENROSE POWER STATION

    Science.gov (United States)

    This demonstration test successfully demonstrated operation of a commercial phosphoric acid fuel cell (FC) on landfill gas (LG) at the Penrose Power Station in Sun Valley, CA. Demonstration output included operation up to 137 kW; 37.1% efficiency at 120 kW; exceptionally low sec...

  5. PSA effect analysis of a design modification of the auxiliary feedwater system for a Westinghouse type plant

    International Nuclear Information System (INIS)

    The auxiliary feedwater system is an important system used to mitigate most accidents considered in probabilistic safety assessment (PSA). The reference plant has produced electric power for about thirty years. Due to age related deterioration and lack of parts, a turbine driven auxiliary feedwater pump (TD AFWP), some valves, and piping of the auxiliary feedwater system should be replaced. This change includes relocation of some valves, installation of valves for maintenance of the steam generator, and a new cross tie line. According to the design change, the Final Safety Analysis Report (FSAR) has been revised. Therefore, this design modification affects the PSA. It is thus necessary to assess the improvement of plant safety. In this paper, the impact of the design change of the auxiliary feedwater system on the PSA is assessed. The results demonstrate that this modification considering the plant safety decreased the total CDF

  6. WORKING PARK-FUEL CELL COMBINED HEAT AND POWER SYSTEM

    Energy Technology Data Exchange (ETDEWEB)

    Allan Jones

    2003-09-01

    This report covers the aims and objectives of the project which was to design, install and operate a fuel cell combined heat and power (CHP) system in Woking Park, the first fuel cell CHP system in the United Kingdom. The report also covers the benefits that were expected to accrue from the work in an understanding of the full technology procurement process (including planning, design, installation, operation and maintenance), the economic and environmental performance in comparison with both conventional UK fuel supply and conventional CHP and the commercial viability of fuel cell CHP energy supply in the new deregulated energy markets.

  7. Retinal ganglion cell distribution and spatial resolving power in elasmobranchs.

    Science.gov (United States)

    Lisney, Thomas J; Collin, Shaun P

    2008-01-01

    The total number, distribution and peak density of presumed retinal ganglion cells was assessed in 10 species of elasmobranch (nine species of shark and one species of batoid) using counts of Nissl-stained cells in retinal wholemounts. The species sampled include a number of active, predatory benthopelagic and pelagic sharks that are found in a variety of coastal and oceanic habitats and represent elasmobranch groups for which information of this nature is currently lacking. The topographic distribution of cells was heterogeneous in all species. Two benthic species, the shark Chiloscyllium punctatum and the batoid Taeniura lymma, have a dorsal or dorso-central horizontal streak of increased cell density, whereas the majority of the benthopelagic and pelagic sharks examined exhibit a more concentric pattern of increasing cell density, culminating in a central area centralis of higher cell density located close to the optic nerve head. The exception is the shark Alopias superciliosus, which possesses a ventral horizontal streak. Variation in retinal ganglion cell topography appears to be related to the visual demands of different habitats and lifestyles, as well as the positioning of the eyes in the head. The upper limits of spatial resolving power were calculated for all 10 species, using peak ganglion cell densities and estimates of focal length taken from cryo-sectioned eyes in combination with information from the literature. Spatial resolving power ranged from 2.02 to 10.56 cycles deg(-1), which is in accordance with previous studies. Species with a lower spatial resolving power tend to be benthic and/or coastal species that feed on benthic invertebrates and fishes. Active, benthopelagic and pelagic species from more oceanic habitats which feed on larger, more active prey, possess a higher resolving power. Additionally, ganglion cells in a juvenile of C. punctatum, were retrogradely-labeled from the optic nerve with biotinylated dextran amine (BDA). A comparison

  8. Microbial Reverse Electrodialysis Cells for Synergistically Enhanced Power Production

    KAUST Repository

    Kim, Younggy

    2011-07-01

    A new type of bioelectrochemical system for producing electrical power, called a microbial reverse-electrodialysis cell (MRC), was developed to increase voltages and power densities compared to those generated individually by microbial fuel cells (MFCs) or reverse electrodialysis (RED) systems. In RED systems, electrode overpotentials create significant energy losses due to thermodynamically unfavorable electrode reactions, and therefore a large number of stacked cells must be used to have significant energy recovery. This results in high capital costs for the large number of membranes, and increases energy losses from pumping water through a large number of cells. In an MRC, high overpotentials are avoided through oxidation of organic matter by exoelectrogenic bacteria on the anode and oxygen reduction on the cathode. An MRC containing only five pairs of RED cells, fed solutions typical of seawater (600 mM NaCl) and river water (12 mM NaCl) at 0.85 mL/min, produced up to 3.6 W/m2 (cathode surface area) and 1.2-1.3 V with acetate as a substrate. Pumping accounted for <2% of the produced power. A higher flow rate (1.55 mL/min) increased power densities up to 4.3 W/m2. COD removal was 98% with a Coulombic efficiency of 64%. Power production by the individual components was substantially lower with 0.7 W/m2 without salinity driven energy, and <0.015 W/m2 with reduced exoelectrogenic activity due to substrate depletion. These results show that the combination of an MFC and a RED stack synergistically increases performance relative to the individual systems, producing a new type of system that can be used to more efficiently capture salinity driven energy from seawater and river water. © 2011 American Chemical Society.

  9. PRESSURIZED SOLID OXIDE FUEL CELL/GAS TURBINE POWER SYSTEM

    Energy Technology Data Exchange (ETDEWEB)

    W.L. Lundberg; G.A. Israelson; R.R. Moritz(Rolls-Royce Allison); S.E. Veyo; R.A. Holmes; P.R. Zafred; J.E. King; R.E. Kothmann (Consultant)

    2000-02-01

    Power systems based on the simplest direct integration of a pressurized solid oxide fuel cell (SOFC) generator and a gas turbine (GT) are capable of converting natural gas fuel energy to electric power with efficiencies of approximately 60% (net AC/LHV), and more complex SOFC and gas turbine arrangements can be devised for achieving even higher efficiencies. The results of a project are discussed that focused on the development of a conceptual design for a pressurized SOFC/GT power system that was intended to generate 20 MWe with at least 70% efficiency. The power system operates baseloaded in a distributed-generation application. To achieve high efficiency, the system integrates an intercooled, recuperated, reheated gas turbine with two SOFC generator stages--one operating at high pressure, and generating power, as well as providing all heat needed by the high-pressure turbine, while the second SOFC generator operates at a lower pressure, generates power, and provides all heat for the low-pressure reheat turbine. The system cycle is described, major system components are sized, the system installed-cost is estimated, and the physical arrangement of system components is discussed. Estimates of system power output, efficiency, and emissions at the design point are also presented, and the system cost of electricity estimate is developed.

  10. Bistable energy harvesting enhancement with an auxiliary linear oscillator

    International Nuclear Information System (INIS)

    Recent work has indicated that linear vibrational energy harvesters with an appended degree-of-freedom (DOF) may be advantageous for introducing new dynamic forms to extend the operational bandwidth. Given the additional interest in bistable harvester designs, which exhibit a propitious snap through effect from one stable state to the other, it is a logical extension to explore the influence of an added DOF to a bistable system. However, bistable snap through is not a resonant phenomenon, which tempers the presumption that the dynamics induced by an additional DOF on bistable designs would inherently be beneficial as for linear systems. This paper presents two analytical formulations to assess the fundamental and superharmonic steady-state dynamics of an excited bistable energy harvester to which is attached an auxiliary linear oscillator. From an energy harvesting perspective, the model predicts that the additional linear DOF uniformly amplifies the bistable harvester response magnitude and generated power for excitation frequencies less than the attachment’s resonance while improved power density spans a bandwidth below this frequency. Analyses predict bandwidths having co-existent responses composed of a unique proportion of fundamental and superharmonic dynamics. Experiments validate key analytical predictions and observe the ability for the coupled system to develop an advantageous multi-harmonic interwell response when the initial conditions are insufficient for continuous high-energy orbit at the excitation frequency. Overall, the addition of an auxiliary linear oscillator to a bistable harvester is found to be an effective means of enhancing the energy harvesting performance and robustness. (paper)

  11. High efficiency carbonate fuel cell/turbine hybrid power cycles

    Energy Technology Data Exchange (ETDEWEB)

    Steinfeld, G. [Energy Research Corp., Danbury, CT (United States)

    1995-10-19

    Carbonate fuel cells developed by Energy Research Corporation, in commercial 2.85 MW size, have an efficiency of 57.9 percent. Studies of higher efficiency hybrid power cycles were conducted in cooperation with METC to identify an economically competitive system with an efficiency in excess of 65 percent. A hybrid power cycle was identified that includes a direct carbonate fuel cell, a gas turbine and a steam cycle, which generates power at a LHV efficiency in excess of 70 percent. This new system is called a Tandem Technology Cycle (TTC). In a TTC operating on natural gas fuel, 95 percent of the fuel is mixed with recycled fuel cell anode exhaust, providing water for the reforming of the fuel, and flows to a direct carbonate fuel cell system which generates 72 percent of the power. The portion of the fuel cell anode exhaust which is not recycled, is burned and heat is transferred to the compressed air from a gas turbine, raising its temperature to 1800{degrees}F. The stream is then heated to 2000{degrees}F in the gas turbine burner and expands through the turbine generating 13 percent of the power. Half the exhaust from the gas turbine flows to the anode exhaust burner, and the remainder flows to the fuel cell cathodes providing the O{sub 2} and CO{sub 2} needed in the electrochemical reaction. Exhaust from the fuel cells flows to a steam system which includes a heat recovery steam generator and stages steam turbine which generates 15 percent of the TTC system power. Studies of the TTC for 200-MW and 20-MW size plants quantified performance, emissions and cost-of-electricity, and compared the characteristics of the TTC to gas turbine combined cycles. A 200-MW TTC plant has an efficiency of 72.6 percent, and is relatively insensitive to ambient temperature, but requires a heat exchanger capable of 2000{degrees}F. The estimated cost of electricity is 45.8 mills/kWhr which is not competitive with a combined cycle in installations where fuel cost is under $5.8/MMBtu.

  12. [Hospital auxiliary staff, between polyvalence and invisibility].

    Science.gov (United States)

    Veissier, Pascale

    2016-01-01

    Often underestimated, hospital auxiliary staff carry out on a daily basis a professional activity that may be difficult to define and/or recognize. What does their work consist in and what are the boundaries of the scope of their activity? Faced with a growing rate of absenteeism among these members of staff in a nursing home for elderly people attached to a hospital, an issue emerges: does the content of their professional activity have an impact on the causes and evolution of this phenomenon? PMID:26976318

  13. Microbial fuel cells as power supply of a low-power temperature sensor

    Science.gov (United States)

    Khaled, Firas; Ondel, Olivier; Allard, Bruno

    2016-02-01

    Microbial fuel cells (MFCs) show great promise as a concomitant process for water treatment and as renewable energy sources for environmental sensors. The small energy produced by MFCs and the low output voltage limit the applications of MFCs. Specific converter topologies are required to step-up the output voltage of a MFC. A Power Management Unit (PMU) is proposed for operation at low input voltage and at very low power in a completely autonomous way to capture energy from MFCs with the highest possible efficiency. The application of sensors for monitoring systems in remote locations is an important approach. MFCs could be an alternative energy source in this case. Powering a sensor with MFCs may prove the fact that wastewater may be partly turned into renewable energy for realistic applications. The Power Management Unit is demonstrated for 3.6 V output voltage at 1 mW continuous power, based on a low-cost 0.7-L MFC. A temperature sensor may operate continuously on 2-MFCs in continuous flow mode. A flyback converter under discontinuous conduction mode is also tested to power the sensor. One continuously fed MFC was able to efficiently and continuously power the sensor.

  14. A magnetorheological clutch for efficient automotive auxiliary device actuation

    Directory of Open Access Journals (Sweden)

    F. Bucchi

    2013-01-01

    Full Text Available In this paper the results of a project funded by Regione Toscana aimed at reducing the power absorption of auxiliary devices in vehicles are presented. In particular the design, testing and application of a magnetorheological clutch (MR is proposed, aimed at disengaging the vacuum pump, which draws in air from the power-brake booster chamber, in order to reduce the device power absorption. Several clutch preliminary studies done to choose the clutch geometry and the magnetic field supply are illustrated. The final choice consisted in an MR clutch with permanent magnet, which satisfied size, torque and fail-safe specifications. The clutch characteristics, in terms of torque versus slip, were obtained experimentally for three different clutch prototypes on an ad-hoc developed test bench.As result of a preliminary simulation, a comparison between the power absorption of a current production vacuum pump, an innovative vacuum pump and both vacuum pumps coupled with the MR clutch is presented. The New European Driving Cycle is considered for simulating the vacuum pump operation both in urban and highway driving. Results show that the use of the innovative vacuum pump reduces the device consumption of about 35%, whereas the use of MR clutch coupled with the innovative vacuum pump reduces it up to about 44% in urban driving and 50% in highway driving.

  15. Reexamination of molecular integrals arising from the Dirac equation. Analytical evaluation of molecular auxiliary functions integrals

    CERN Document Server

    Bagci, A

    2016-01-01

    The author in his previous works were presented a numerical integration method, namely, global-adaptive with the Gauss-Kronrod numerical integration extension in order to accurate calculation of molecular auxiliary functions integrals involve power functions with non-integer exponents. They are constitute elements of molecular integrals arising in Dirac equation when Slater-type orbitals with non-integer principal quantum numbers are used. Binomial series representation of power functions method, so far, is used for analytical evaluation of the molecular auxiliary function integrals however, intervals of integration cover areas beyond the condition of convergence. In the present study, analytical evaluation of these integrals is re-examined. They are expressed via prolate spheroidal coordinates. An alternative analytical approximation are derived. Slowly convergent binomial series representation formulae for power functions is investigated through nonlinear sequence transformations for the acceleration of con...

  16. Inverters for interfacing of solar cells with the power grid

    Science.gov (United States)

    Karamanzanis, G. N.; Jackson, R. D.

    In this work, based on a research course in the Engineering Dep. Cambridge University, some non-classical inverter circuits are studied. They can be used for interfacing solar cells with the power grid at low voltage (230V) and at low power level. They are based on d.c. choppers which have a fast switching transistor. Their theoretical efficiency is 100 percent and they provide a satisfactory output current waveform in phase to the a.c. line voltage. The problems of control are also studied using a suitable mathematical model.

  17. Solid Oxide Fuel Cell Technology Stationary Power Application Project

    Energy Technology Data Exchange (ETDEWEB)

    Joseph Pierre

    2009-03-05

    The objectives of this program were to: (1) Develop a reliable, cost-effective, and production-friendly technique to apply the power-enhancing layer at the interface of the air electrode and electrolyte of the Siemens SOFC; (2) Design, build, install, and operate in the field two 5 kWe SOFC systems fabricated with the state-of-the-art cylindrical, tubular cell and bundle technology and incorporating advanced module design features. Siemens successfully demonstrated, first in a number of single cell tests and subsequently in a 48-cell bundle test, a significant power enhancement by employing a power-enhancing composite interlayer at the interface between the air electrode and electrolyte. While successful from a cell power enhancement perspective, the interlayer application process was not suitable for mass manufacturing. The application process was of inconsistent quality, labor intensive, and did not have an acceptable yield. This program evaluated the technical feasibility of four interlayer application techniques. The candidate techniques were selected based on their potential to achieve the technical requirements of the interlayer, to minimize costs (both labor and material), and suitably for large-scale manufacturing. Preliminary screening, utilizing lessons learned in manufacturing tubular cells, narrowed the candidate processes to two, ink-roller coating (IRC) and dip coating (DC). Prototype fixtures were successfully built and utilized to further evaluate the two candidate processes for applying the interlayer to the high power density Delta8 cell geometry. The electrical performance of interlayer cells manufactured via the candidate processes was validated. Dip coating was eventually selected as the application technique of choice for applying the interlayer to the high power Delta8 cell. The technical readiness of the DC process and product quality was successfully and repeatedly demonstrated, and its throughput and cost are amenable to large scale

  18. Electrical Power Distribution and Control Modeling and Analysis

    Science.gov (United States)

    Fu, Johnny S.; Liffring, Mark; Mehdi, Ishaque S.

    2001-01-01

    This slide presentation reviews the use of Electrical Power Distribution and Control (EPD&C) Modeling and how modeling can support analysis. The presentation discusses using the EASY5 model to simulate and analyze the Space Shuttle Electric Auxiliary Power Unit. Diagrams of the model schematics are included, as well as graphs of the battery cell impedance, hydraulic load dynamics, and EPD&C response to hydraulic load variations.

  19. High power nickel - cadmium cells with fiber electrodes (FNC)

    International Nuclear Information System (INIS)

    Nickel cadmium batteries differ greatly in their mechanical design and construction of the electrodes. Using available electrode constructions, batteries are designed which meet the requirements of specific applications and offer optimum performance. Pocket- and tubular cells are basically developed with the technology of the year 1895. Since then some improvements with todays technology have been made. The sintered cells use the technology of the 1930's and they are still limited to high power application. With this knowledge and the technology of today the fiber-structured nickel electrode (FNC) was developed at DAUG laboratory, a subsidiary company of Mercedes-Benz and Volkswagen. After ten years of experience in light weight prototype batteries for electric vehicles (1-2), the system was brought into production by a new company, DAUG-HOPPECKE. Characteristics of fiber electrodes: thickness and size can be easily changed; pure active materials are used; high conductor density; high elasticity of the structure; high porosity. Since 1983 NiCd-batteries with fiber-structured nickel electrodes (FNC) have been in production. Starting with the highly demanded cell-types for low, medium and high performance called L, M and H according to IEC 623 for low, medium and high performance applications, the program was recently completed with the X-type cell for very high power, as an alternative to sintered cells

  20. Fuel cells - a new contributor to stationary power

    Science.gov (United States)

    Dufour, Angelo U.

    Stationary power generation historically started as distributed generation near the user, with the configuration of a very open market, where a lot of small competing utilities were offering electricity to the customers. At a second time it became a `monopolistic' business because of technical reasons. Big steam turbines and electric generators, allowing better efficiencies, were more conveniently installed in very large power plants, necessarily located in sites far away from where the power was needed, and the transmission losses were bounded by AC high voltage technology. The Governments were, therefore, trying to balance the power of monopolies, that were limiting the economical development of the countries, by strengthening the concept of electrical energy price public control and, alternatively, by establishing rules to allow a free flow of electricity from one region to the other, or taking direct control through ownership of big and small utilities. The most effective way of making the electric energy system competitive has proved to be the opening of a partial competition in the generation field by forcing the utilities to compare the cost of their energy, produced with new centralised plants, to the price of the available energy, coming from combined heat and power dispersed generators. In fact, with reference to this cost, all the peculiar features of large central stations and dispersed generators were taken into account, like the widespread use of natural gas, the investment risk reduction with single smaller increments of capacity, the transmission and distribution siting difficulties and high costs, the improved system reliability, and, finally, the high quality electric power. Fuel Cells are a recently become available technology for distributed electrical energy production, because they share the main typical aspects, relevant for a distributed power system, like compatibility with other modular subsystem packages, fully automation possibility

  1. Efficiency measurement and uncertainty discussion of an electric engine powered by a "self-breathing" and "self-humidified" proton exchange membrane fuel cell.

    Science.gov (United States)

    Schiavetti, Pierluigi; Del Prete, Zaccaria

    2007-08-01

    The efficiency of an automotive engine based on a "self-breathing" and "self-humidified" proton exchange membrane fuel cell stack (PEM FC) connected to a dc brushless electrical motor was measured under variable power load conditions. Experiments have been carried out on a small scale 150 W engine model. After determining the fuel cell static polarization curve and the time response to power steps, the system was driven to copy on the test bench a "standard urban load cycle" and its instantaneous efficiencies were measured at an acquisition rate of 5 Hz. The integral system efficiency over the entire urban load cycle, comprising the losses of the unavoidable auxiliary components of the engine, was then calculated. The fuel cell stack was operated mainly in "partial" dead-end mode, with a periodic anode flow channel purging, and one test was carried out in "pure" dead-end mode, with no anode channel purging. An uncertainty analysis of the efficiencies was carried out, taking into account either type A and type B evaluation methods, strengthening the discussion about the outcomes obtained for a system based on this novel simplified FC type. For our small scale engine we measured over the standard urban cycle, on the basis of the H(2) high heating value (HHV), a tank-to-wheel integral efficiency of (18.2+/-0.8)%, when the fuel cell was operated with periodic flow channel purging, and of (21.5+/-1.3)% in complete dead-end operation mode. PMID:17764355

  2. Investigation of Solar Cells Power Degradation Due to Electrostatic Discharge

    Directory of Open Access Journals (Sweden)

    Hossein Fayazi

    2014-07-01

    Full Text Available Satellites are surrounded with protons, electrons and heavy charged particles. Space radiation impact on satellite sub-systems cause several anomalies which are important problem for satellite designers. Until recently, the majority of spacecraft primary power systems used solar arrays and rechargeable batteries to supply 28 V. For low-inclination spacecraft, 28 V systems have not been observed to arc. As the power requirements for spacecraft increased, however, high-voltage solar arrays were baselined to minimize total mass and increase power production efficiency. With the advent of 100 V systems in the late 1980s, arcing began to be observed on a number of spacecraft. The mechanism proposed in this paper, described electrical and physical degradation of solar cells due to electrostatic discharge anomalies on satellites. The cell was characterized again after arcing to determine the change in efficiency. This paper details the process for designing the circuit to create the arcing, and the different setups used to degrade the cells electrically and physically. It also describes the final setups to be used in space laboratory. This model is designed using Matlab and SPENVIS. Identification and simulation this mechanism is an important step in solar array design for space application

  3. Specification for dispersed fuel-cell generator

    Science.gov (United States)

    Handley, L. M.; Cohen, R.

    1981-11-01

    A general description and performance definition for a standard 11-mw fuel cell power plant designed for electric utility dispersed-generation applications are provided. Additional features available at the option of the purchaser are also described. The power plant can operate singly or grouped with other power plants to produce larger mutli-megawatt power stations. A 33-mw station is discussed as representative of multiple power plant installations. The power plant specification defines power rating, heat rate, fuels, operating modes, siting characteristics, and available options. A general description included in the attachments covers equipment, typical site arrangement, auxiliary subsystems, maintenance, fuel flexibility, and general fluid and electrical schematics.

  4. ERC product improvement activities for direct fuel cell power plants

    Energy Technology Data Exchange (ETDEWEB)

    Bentley, C.; Carlson, G.; Doyon, J. [and others

    1995-08-01

    This program is designed to advance the carbonate fuel cell technology from the current power plant demonstration status to the commercial design in an approximately five-year period. The specific objectives which will allow attainment of the overall program goal are: (1) Define market-responsive power plant requirements and specifications, (2) Establish the design for a multifuel, low-cost, modular, market-responsive power plant, (3) Resolve power plant manufacturing issues and define the design for the commercial manufacturing facility, (4) Define the stack and BOP equipment packaging arrangement and define module designs, (5) Acquire capability to support developmental testing of stacks and BOP equipment as required to prepare for commercial design, and (6) Resolve stack and BOP equipment technology issues and design, build, and field test a modular commercial prototype power plant to demonstrate readiness for commercial entry. A seven-task program, dedicated to attaining objective(s) in the areas noted above, was initiated in December 1994. Accomplishments of the first six months are discussed in this paper.

  5. Increased power density from a spiral wound microbial fuel cell.

    Science.gov (United States)

    Jia, Boyang; Hu, Dawei; Xie, Beizhen; Dong, Kun; Liu, Hong

    2013-03-15

    Using Microbial fuel cell (MFC) to convert organic and inorganic matter into electricity is of great interest for powering portable devices, which is now still limited by the output of MFC. In this study, a spiral wound MFC (SWMFC) with relatively large volume normalized surface area of separator (4.2 cm(2)/ml) was fabricated to enhance power generation. Compared with double-membrane MFC (DMMFC) and conventional double chamber MFC (DCMFC), the power density of SWMFC increased by 42% and 99% resulted from its lower internal resistance. Besides larger separator area, the better performance of SWMFC benefited from its structure sandwiching the cathodes between two separators. This point was proved again by a comparison of another DCMFC and a triple chamber MFC (TCMFC) as well as a simulation using finite element method. Moreover, the feature of SWMFC was more convenient and compact to scale up. Therefore, SWMFC provides a promising configuration for high power output as a portable power source. PMID:23116542

  6. Self-powered supercapacitive microbial fuel cell: The ultimate way of boosting and harvesting power.

    Science.gov (United States)

    Santoro, Carlo; Soavi, Francesca; Serov, Alexey; Arbizzani, Catia; Atanassov, Plamen

    2016-04-15

    In this work, for the first time, we demonstrate a supercapacitive microbial fuel cell which integrates the energy harvesting function of a microbial fuel cell (MFC) with the high-power operation of an internal supercapacitor. The pursued strategies are: (i) the increase of the cell voltage by the use of high potential cathodes like bilirubin oxidase (BOx) or iron-aminoantipyrine (Fe-AAPyr); (ii) the use of an additional capacitive electrode (additional electrode, AdE) which is short-circuited with the MFC cathode and coupled with the MFC anode (MFC-AdE). The high working potential of BOx cathode and the low impedances of the additional capacitive electrode and the MFC anode permitted to achieve up to 19 mW (84.4 Wm(-2), 152 Wm(-3)), the highest power value ever reported for MFCs. Exploiting the supercapacitive properties of the MFC electrodes allows the system to be simpler, cheaper and more efficient without additional electronics management added with respect to an MFC/external supercapacitor coupling. The use of the AdE makes it possible to decouple energy and power and to achieve recharge times in the order of few seconds making the system appealing for practical applications. PMID:26615513

  7. An Intelligent Power Controller for Hybrid DC Micro Grid Power System

    DEFF Research Database (Denmark)

    Hajizadeh, Amin; Norum, Lars; Hassanzadeh, Fattah;

    2016-01-01

    In this paper, an intelligent power management strategy is proposed for hybrid DC microgrid, including wind turbine, fuel cell and battery energy storage. The considered wind turbine has a permanent magnet synchronous generator (PMSG). In the considered structure, wind turbine operates as the main...... energy source while the fuel cell and battery bank are both auxiliary power sources. The main control objectives are to supply the load power continuously and all power sources generate power in normal conditions. Hence, the fuel cell and battery bank are managed such that the system will operate in...... normal condition and fuel cell will not generate any excessive power. The proposed control scheme is based on the fuzzy algorithm. All Simulations in variant operational modes are performed by MATLAB-Simulink and results show the effectiveness of the proposed control strategy....

  8. Evaluating the performance of microbial fuel cells powering electronic devices

    Energy Technology Data Exchange (ETDEWEB)

    Dewan, Alim; Beyenal, Haluk [Gene and Linda Voiland School of Chemical Engineering and Bioengineering, Center for Environmental, Sediment and Aquatic Research, Pullman, WA (United States); Donovan, Conrad; Heo, Deukhyoun [School of Electrical Engineering and Computer Science, Washington State University, Pullman, WA 99163-2710 (United States)

    2010-01-01

    A microbial fuel cell (MFC) is capable of powering an electronic device if we store the energy in an external storage device, such as a capacitor, and dispense that energy intermittently in bursts of high-power when needed. Therefore its performance needs to be evaluated using an energy-storing device such as a capacitor which can be charged and discharged rather than other evaluation techniques, such as continuous energy dissipation through a resistor. In this study, we develop a method of testing microbial fuel cell performance based on storing energy in a capacitor. When a capacitor is connected to a MFC it acts like a variable resistor and stores energy from the MFC at a variable rate. In practice the application of this method to testing microbial fuel cells is very challenging and time consuming; therefore we have custom-designed a microbial fuel cell tester (MFCT). The MFCT evaluates the performance of a MFC as a power source. It uses a capacitor as an energy storing device and waits until a desired amount of energy is stored then discharges the capacitor. The entire process is controlled using an analog-to-digital converter (ADC) board controlled by a custom-written computer program. The utility of our method and the MFCT is demonstrated using a laboratory microbial fuel cell (LMFC) and a sediment microbial fuel cell (SMFC). We determine (1) how frequently a MFC can charge a capacitor, (2) which electrode is current-limiting, (3) what capacitor value will allow the maximum harvested energy from a MFC, which is called the ''optimum charging capacitor value,'' and (4) what capacitor charging potential will harvest the maximum energy from a MFC, which is called the ''optimum charging potential.'' Using a LMFC we find that (1) the time needed to charge a 3-F capacitor from 0 to 500 mV is 108 min, (2) the optimum charging capacitor value is 3 F, and (3) the optimum charging potential is 300 mV. Using a SMFC we find that (1

  9. Cell heterogeneity problems in the analysis of zero power experiments

    International Nuclear Information System (INIS)

    Methods are described for treating plate and pin cell heterogeneity in the preparation of broad group cross-sections used in the analysis of zero power fast reactor experiments. Methods used at Karlsruhe and Winfrith are summarised and compared, with particular reference to the treatment of resonance shielding, the calculation of broad group spatial fine structure, the treatment of leakage and the calculation of anisotropic diffusion coefficients. The problems of cells near boundaries such as core-breeder interfaces and of singularities such as control rods are also considered briefly. Numerical studies carried out to investigate approximations in the methods are described. These include tests of the accuracy of one-dimensional cell modelling techniques, and the validation by Monte Carlo of methods for treating streaming in the calculation of diffusion coefficients. Comparisons are shown between the heterogeneity effects calculated by the Karlsruhe and Winfrith methods for typical pin and plate cells used in the BIZET experimental programme, and their effect in a whole reactor calculation is indicated. Comparisons are given with measurements which provide tests of the heterogeneity calculations. These include reaction rate scans within pin and plate cells, and reaction rate measurements across sectors of pin and plate fuel, where the flux tilt is determined by the relative reactivity of the pin and plate cells. Finally, the heterogeneity problems arising in the interpretation of reaction rate measurements are discussed. (author)

  10. Fission Yeast Germinal Center (GC) Kinase Ppk11 Interacts with Pmo25 and Plays an Auxiliary Role in Concert with the Morphogenesis Orb6 Network (MOR) in Cell Morphogenesis*

    OpenAIRE

    Goshima, Tetsuya; Kume, Kazunori; Koyano, Takayuki; Ohya, Yoshikazu; Toda, Takashi; Hirata, Dai

    2010-01-01

    How cell morphology and the cell cycle are coordinately regulated is a fundamental subject in cell biology. In fission yeast, 2 germinal center kinases (GCKs), Sid1 and Nak1, play an essential role in septation/cytokinesis and cell separation/cell polarity control, respectively, as components of the septation initiation network (SIN) and the morphogenesis Orb6 network (MOR). Here we show that a third GCK, Ppk11, is also required for efficient cell separation particularly, at a high temperatur...

  11. Minimal RED Cell Pairs Markedly Improve Electrode Kinetics and Power Production in Microbial Reverse Electrodialysis Cells

    KAUST Repository

    Cusick, Roland D.

    2013-12-17

    Power production from microbial reverse electrodialysis cell (MRC) electrodes is substantially improved compared to microbial fuel cells (MFCs) by using ammonium bicarbonate (AmB) solutions in multiple RED cell pair stacks and the cathode chamber. Reducing the number of RED membranes pairs while maintaining enhanced electrode performance could help to reduce capital costs. We show here that using only a single RED cell pair (CP), created by operating the cathode in concentrated AmB, dramatically increased power production normalized to cathode area from both acetate (Acetate: from 0.9 to 3.1 W/m 2-cat) and wastewater (WW: 0.3 to 1.7 W/m2), by reducing solution and charge transfer resistances at the cathode. A second RED cell pair increased RED stack potential and reduced anode charge transfer resistance, further increasing power production (Acetate: 4.2 W/m2; WW: 1.9 W/m2). By maintaining near optimal electrode power production with fewer membranes, power densities normalized to total membrane area for the 1-CP (Acetate: 3.1 W/m2-mem; WW: 1.7 W/m2) and 2-CP (Acetate: 1.3 W/m2-mem; WW: 0.6 W/m2) reactors were much higher than previous MRCs (0.3-0.5 W/m2-mem with acetate). While operating at peak power, the rate of wastewater COD removal, normalized to reactor volume, was 30-50 times higher in 1-CP and 2-CP MRCs than that in a single chamber MFC. These findings show that even a single cell pair AmB RED stack can significantly enhance electrical power production and wastewater treatment. © 2013 American Chemical Society.

  12. Brane worlds in gravity with auxiliary fields

    International Nuclear Information System (INIS)

    Recently, Pani et al. explored a new theory of gravity by adding nondynamical fields, i.e., gravity with auxiliary fields (Phys Rev D 88:121502, 2013). In this gravity theory, higher-order derivatives of matter fields generically appear in the field equations. In this paper we extend this theory to any dimensions and discuss the thick braneworld model in five dimensions. Domain wall solutions are obtained numerically. The stability of the brane system under tensor perturbations is analyzed. We find that the system is stable under tensor perturbations and the gravity zero mode is localized on the brane. Therefore, the four-dimensional Newtonian potential can be realized on the brane. (orig.)

  13. Brane worlds in gravity with auxiliary fields

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Bin; Liu, Yu-Xiao; Yang, Ke [Lanzhou University, Institute of Theoretical Physics, Lanzhou (China)

    2015-02-01

    Recently, Pani et al. explored a new theory of gravity by adding nondynamical fields, i.e., gravity with auxiliary fields (Phys Rev D 88:121502, 2013). In this gravity theory, higher-order derivatives of matter fields generically appear in the field equations. In this paper we extend this theory to any dimensions and discuss the thick braneworld model in five dimensions. Domain wall solutions are obtained numerically. The stability of the brane system under tensor perturbations is analyzed. We find that the system is stable under tensor perturbations and the gravity zero mode is localized on the brane. Therefore, the four-dimensional Newtonian potential can be realized on the brane. (orig.)

  14. Fuel cell - An alternative for power and heat generating

    International Nuclear Information System (INIS)

    One of the most promising energy generating technologies is the fuel cell (FC) because of its high efficiency and low emissions. There are even zero chemical emissions FC and cogeneration plants based on FC generate low heat emissions too. FC was invented 160 years ago but it was usually used only since 1960 in space missions. A FC farm tractor was tested 40 years ago. FC was again taken into account by power engineering since 1990 and it is now considered a credible alternative to power and heat generating. The thermal power engineers (and not only they) have two problems of cardinal importance for mankind to solve: - Energy saving (by increasing of energy generating efficiency) and - Environmental protection (by reducing chemical and heat emissions). The possibilities to use FC to generate power and heat are practically endless: on the earth, in the air and outer space, by and under water, in numberless areas of human activities. FC are now powering buses, cars, trains, boats, plains, scooters, highway road signs etc. There are already miniature FC for portable electronics. Homes, schools, hospitals, institutes, banks, police stations, etc are using FC to generate power and heat for their facilities. The methane gas produced by wastewater treatment plants and landfills is converted into electricity by using FC. Being less expensive than nuclear and solar source of energy, FC is now generally used in the space missions (in addition FC generates water). In this work an analysis of the possibilities to use FC especially for combined power and heat generating is presented. FC is favourite as energy source in space missions because it is less expensive than nuclear or solar sources. All major automobile companies have FC powered automobiles in testing stage. Mini FC for phone, laptop, and electronics are already on market. FC will be use to pagers, video recorders, small portable tools, miniature robots, special devices as hearing aid various devices, smoke detectors

  15. Cloud Instrument Powered by Solar Cell Sends Data to Pachube

    Directory of Open Access Journals (Sweden)

    Doru Ursutiu

    2010-11-01

    Full Text Available Despite the economic downturn, there have been quite a few new developments in the world of remote measurements lately. Tag4M (www.tag4m.com introduced the concept of cloud instrument where sensors connected to WiFi tags send data to off-the-shelf Access Points which are part of the WiFi infrastructure that exists in enterprises, retail outlets, factories, and warehouses. Access Points route the data to the Internet where specialized web applications receive the information for processing and display. One of these specialized web applications is Pachube, (http://www.pachube.com which bills itself as a “real-time data brokerage platform”. Pachube enables people to tag and share real time sensor data from objects, devices and spaces around the world. This article presents the pachube cloud instrument where sensors connected to Tag4M WiFi tags send digitized data to www.pachube.com for public display. The article contains very detailed analysis of the solar cell power source that is used to continuously power the Tag4M tag during this application. Cloud Instruments powered by solar cells enable people around the world to share real time sensor data using web pages on the Internet. This is a very interesting and exciting technology development that we want to bring to your attention.

  16. Assessment of Microbial Fuel Cell Configurations and Power Densities

    KAUST Repository

    Logan, Bruce E.

    2015-07-30

    Different microbial electrochemical technologies are being developed for a many diverse applications, including wastewater treatment, biofuel production, water desalination, remote power sources, and as biosensors. Current and energy densities will always be limited relative to batteries and chemical fuel cells, but these technologies have other advantages based on the self-sustaining nature of the microorganisms that can donate or accept electrons from an electrode, the range of fuels that can be used, and versatility in the chemicals that can be produced. The high cost of membranes will likely limit applications of microbial electrochemical technologies that might require a membrane. For microbial fuel cells, which do not need a membrane, questions remain on whether larger-scale systems can produce power densities similar to those obtained in laboratory-scale systems. It is shown here that configuration and fuel (pure chemicals in laboratory media versus actual wastewaters) remain the key factors in power production, rather than the scale of the application. Systems must be scaled up through careful consideration of electrode spacing and packing per unit volume of reactor.

  17. Safety Assessment of Auxiliary Power Unit (APU) System for Civil Aircraft Based on Dynamic Fault Tree Analysis (DFTA)%基于动态故障树分析的民用飞机辅助动力装置系统安全性评估

    Institute of Scientific and Technical Information of China (English)

    王栋

    2014-01-01

    Traditional fault tree analysis method is widely used for system safety assessment in civil aviation indus-try , but dynamic characteristics of systems/subsystems, including operational sequencing interpretation, spare and redundancy expression cannot be represented by traditional fault trees. On the other hand, civil aircraft auxiliary power unit ( APU) often operates as a redundant system and its behavior can be described by using dynamic fault tree appropriately. As a result, the interest of DFTA application is focused on APU system safety assessment. In this paper, two kinds of dynamic gates ( PAND and CSP) were introduced firstly. Their quantitative calculations were presented by applying Markov model. Then two typical cases with auxiliary power unit ( APU) system safety assess-ment were analyzed by traditional fault tree and dynamic fault tree respectively. Finally the comparison between two kinds of Fault Tree Analysis ( FTA ) was provided and the result indicates that Dynamic Fault Tree Analysis ( DFTA) method based on proper application reaches remarkable accuracy ,and the calculation cost is acceptable when second-order approximation of exponential distribution function is applied.%在民用航空工业领域,传统的故障树分析方法广泛运用于系统安全性评估。然而,包含系统/子系统运行的时序阐述以及备份、冗余表达在内的动态特性不能通过传统故障树呈现。另一方面,民用飞机辅助动力装置( APU)经常作为一个冗余系统运作,因而其行为可以通过运用动态故障树进行适当的描述。所以APU的这种特性激发了动态故障树分析在APU系统安全性评估上应用的关注。首先介绍了两种动态门(优先与门和冷备件门),其定量计算通过施用马尔可夫模型来呈现;然后分别通过传统故障树以及动态故障树分析了APU系统安全性评估的两个典型案例;最后进行了两种故障树分析( FTA )的比较,其

  18. Synthesis of passive lossless metasurfaces using auxiliary fields for reflectionless beam splitting and perfect reflection

    CERN Document Server

    Epstein, Ariel

    2016-01-01

    We introduce a paradigm for accurate design of metasurfaces for intricate beam manipulation, implementing functionalities previously considered impossible to achieve with passive lossless elements. The key concept involves self-generation of auxiliary evanescent fields which facilitate the required local power conservation, without interfering with the device performance in the far field. We demonstrate our scheme by presenting exact reactive solutions to the challenging problems of reflectionless beam splitting and perfect reflection, verified via full wave simulations.

  19. Ignition delay of a pulsed inductively coupled plasma (ICP) in tandem with an auxiliary ICP

    Science.gov (United States)

    Liu, Lei; Sridhar, Shyam; Donnelly, Vincent M.; Economou, Demetre J.

    2015-12-01

    Plasma ignition delays were observed in a ‘main’ inductively coupled plasma (ICP), in tandem with an ‘auxiliary’ ICP. The Faraday-shielded ICPs were separated by a grounded metal grid. Power (13.56 MHz) to the main ICP was pulsed with a frequency of 1 kHz, while the auxiliary ICP was operated in continuous wave (cw) mode. In chlorine plasmas, ignition delay was observed for duty cycles greater than 60% and, in contrast to expectation, the delay was longer with increasing duty cycle up to ~99.5%. The ignition delay could be varied by changing the auxiliary and/or main ICP power. Langmuir probe measurements provided the temporal evolution of electron temperature, and electron and positive ion densities. These measurements revealed that the plasma was ignited shortly after the decaying positive ion density (n +), in the afterglow of the main ICP, reached the density ({{n}+},\\text{aux} ) prevailing when only the auxiliary ICP was powered. At that time, production of electrons began to dominate their loss in the main ICP, due to hot electron injection from the auxiliary ICP. As a result, {{n}\\text{e}} increased from a value below {{n}\\text{e,\\text{aux}}} , improving inductive power coupling efficiency, further increasing plasma density leading to plasma ignition. Plasma ignition delay occurred when the afterglow of the pulsed plasma was not long enough for the ion density to reach {{n}+},\\text{aux} during the afterglow. Besides Cl2, plasma ignition delays were also observed in other electronegative gases (SF6, CF4/O2 and O2) but not in an electropositive gas (Ar).

  20. 47 CFR 80.290 - Auxiliary receiving antenna.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Auxiliary receiving antenna. 80.290 Section 80... antenna. An auxiliary receiving antenna must be provided when necessary to avoid unauthorized interruption or reduced efficiency of the required watch because the normal receiving antenna is not...

  1. The German and English Auxiliary Systems and Complex Predicates

    Science.gov (United States)

    McCormick, Terrence C.

    1976-01-01

    This paper explores the auxiliary systems of English and German and the use of the auxiliary verbs in various complex predicate structures in the two languages. It aims at alleviating two types of problems in learning German involving governing patterns and ordering problems in clauses. (CHK)

  2. Advanced coal gasifier-fuel cell power plant systems design

    Science.gov (United States)

    Heller, M. E.

    1983-01-01

    Two advanced, high efficiency coal-fired power plants were designed, one utilizing a phosphoric acid fuel cell and one utilizing a molten carbonate fuel cell. Both incorporate a TRW Catalytic Hydrogen Process gasifier and regenerator. Both plants operate without an oxygen plant and without requiring water feed; they, instead, require makeup dolomite. Neither plant requires a shift converter; neither plant has heat exchangers operating above 1250 F. Both plants have attractive efficiencies and costs. While the molten carbonate version has a higher (52%) efficiency than the phosphoric acid version (48%), it also has a higher ($0.078/kWh versus $0.072/kWh) ten-year levelized cost of electricity. The phosphoric acid fuel cell power plant is probably feasible to build in the near term: questions about the TRW process need to be answered experimentally, such as weather it can operate on caking coals, and how effective the catalyzed carbon-dioxide acceptor will be at pilot scale, both in removing carbon dioxide and in removing sulfur from the gasifier.

  3. Thermally regenerative hydrogen/oxygen fuel cell power cycles

    Science.gov (United States)

    Morehouse, J. H.

    1986-01-01

    Two innovative thermodynamic power cycles are analytically examined for future engineering feasibility. The power cycles use a hydrogen-oxygen fuel cell for electrical energy production and use the thermal dissociation of water for regeneration of the hydrogen and oxygen. The TDS (thermal dissociation system) uses a thermal energy input at over 2000 K to thermally dissociate the water. The other cycle, the HTE (high temperature electrolyzer) system, dissociates the water using an electrolyzer operating at high temperature (1300 K) which receives its electrical energy from the fuel cell. The primary advantages of these cycles is that they are basically a no moving parts system, thus having the potential for long life and high reliability, and they have the potential for high thermal efficiency. Both cycles are shown to be classical heat engines with ideal efficiency close to Carnot cycle efficiency. The feasibility of constructing actual cycles is investigated by examining process irreversibilities and device efficiencies for the two types of cycles. The results show that while the processes and devices of the 2000 K TDS exceed current technology limits, the high temperature electrolyzer system appears to be a state-of-the-art technology development. The requirements for very high electrolyzer and fuel cell efficiencies are seen as determining the feasbility of the HTE system, and these high efficiency devices are currently being developed. It is concluded that a proof-of-concept HTE system experiment can and should be conducted.

  4. Fuel economy and range estimates for fuel cell powered automobiles

    Energy Technology Data Exchange (ETDEWEB)

    Steinbugler, M.; Ogden, J. [Princeton Univ., NJ (United States)

    1996-12-31

    While a number of automotive fuel cell applications have been demonstrated, including a golf cart, buses, and a van, these systems and others that have been proposed have utilized differing configurations ranging from direct hydrogen fuel cell-only power plants to fuel cell/battery hybrids operating on reformed methanol. To date there is no clear consensus on which configuration, from among the possible combinations of fuel cell, peaking device, and fuel type, is the most likely to be successfully commercialized. System simplicity favors direct hydrogen fuel cell vehicles, but infrastructure is lacking. Infrastructure favors a system using a liquid fuel with a fuel processor, but system integration and performance issues remain. A number of studies have analyzed particular configurations on either a system or vehicle scale. The objective of this work is to estimate, within a consistent framework, fuel economies and ranges for a variety of configurations using flexible models with the goal of identifying the most promising configurations and the most important areas for further research and development.

  5. The Power and the Promise of Cell Reprogramming: Personalized Autologous Body Organ and Cell Transplantation

    Directory of Open Access Journals (Sweden)

    Ana Belen Alvarez Palomo

    2014-04-01

    Full Text Available Reprogramming somatic cells to induced pluripotent stem cells (iPSCs or direct reprogramming to desired cell types are powerful and new in vitro methods for the study of human disease, cell replacement therapy, and drug development. Both methods to reprogram cells are unconstrained by the ethical and social questions raised by embryonic stem cells. iPSC technology promises to enable personalized autologous cell therapy and has the potential to revolutionize cell replacement therapy and regenerative medicine. Potential applications of iPSC technology are rapidly increasing in ambition from discrete cell replacement applications to the iPSC assisted bioengineering of body organs for personalized autologous body organ transplant. Recent work has demonstrated that the generation of organs from iPSCs is a future possibility. The development of embryonic-like organ structures bioengineered from iPSCs has been achieved, such as an early brain structure (cerebral organoids, bone, optic vesicle-like structures (eye, cardiac muscle tissue (heart, primitive pancreas islet cells, a tooth-like structure (teeth, and functional liver buds (liver. Thus, iPSC technology offers, in the future, the powerful and unique possibility to make body organs for transplantation removing the need for organ donation and immune suppressing drugs. Whilst it is clear that iPSCs are rapidly becoming the lead cell type for research into cell replacement therapy and body organ transplantation strategies in humans, it is not known whether (1 such transplants will stimulate host immune responses; and (2 whether this technology will be capable of the bioengineering of a complete and fully functional human organ. This review will not focus on reprogramming to iPSCs, of which a plethora of reviews can be found, but instead focus on the latest developments in direct reprogramming of cells, the bioengineering of body organs from iPSCs, and an analysis of the immune response induced by i

  6. Analysis and Test of a Proton Exchange Membrane Fuel Cell Power System for Space Power Applications

    Science.gov (United States)

    Vasquez, Arturo; Varanauski, Donald; Clark, Robert, Jr.

    2000-01-01

    An effort is underway to develop a prototype Proton Exchange Membrane (PEM) Fuel Cell breadboard system for fuhlre space applications. This prototype will be used to develop a comprehensive design basis for a space-rated PEM fuel cell powerplant. The prototype system includes reactant pressure regulators, ejector-based reactant pumps, a 4-kW fuel cell stack and cooling system, and a passive, membranebased oxygen / water separator. A computer model is being developed concurrently to analytically predict fluid flow in the oxidant reactant system. Fuel cells have historically played an important role in human-rated spacecraft. The Gemini and Apollo spacecraft used fuel cells for vehicle electrical power. The Space Shuttle currently uses three Alkaline Fuel Cell Powerplants (AFCP) to generate all of the vehicle's 15-20kW electrical power. Engineers at the Johnson Space Center have leveraged off the development effort ongoing in the commercial arena to develop PEM fuel cel ls for terrestrial uses. The prototype design originated from efforts to develop a PEM fuel cell replacement for the current Space Shuttle AFCP' s. In order to improve on the life and an already excellent hi storical record of reliability and safety, three subsystems were focused on. These were the fuel cell stack itself, the reactant circulation devices, and reactant / product water separator. PEM fuel cell stack performance is already demonstrating the potential for greater than four times the useful life of the current Shuttle's AFCP. Reactant pumping for product water removal has historically been accomplished with mechanical pumps. Ejectors offer an effective means of reactant pumping as well as the potential for weight reduction, control simplification, and long life. Centrifugal water separation is used on the current AFCP. A passive, membrane-based water separator offers compatibility with the micro-gravity environment of space, and the potential for control simplification, elimination of

  7. Separate-effect Test for Cooling Performance of PAFS(Passive Auxiliary Feedwater System)

    International Nuclear Information System (INIS)

    APR+ (Advanced Power Reactor Plus) is a next generation nuclear power plant being developed in Korea. It adopts PAFS (Passive Auxiliary Feedwater System) for the steam generator (SG) instead of an active auxiliary feedwater system for the conventional nuclear power plant (NPP). It can replace the conventional active auxiliary feedwater system for the SG by a passive way. It is composed of a steam-supply line, a condensation heat exchanger, a return-water line, and a PCCT (Passive Condensate Cooling Tank). When the water level in the SG becomes lower than 25% of the wide range of the water level transmitter during an accident situation, the actuation valve at the return-water line is open and then the natural convection flow of the PAFS can be made. To validate a cooling performance of PAFS, separate effect test loop, which is named PASCAL (PAFS Condensing heat removal Assessment Loop) was constructed at KAERI (Korea Atomic Energy Research Institute) for investigating the cooling capability of the condensation heat exchanger and the characteristic of the natural convection. This study focuses on the experimental study of the separate effect test with PASCAL facility. From the experimental results, two-phase flow phenomena in the condensation heat exchanger and PCCT are investigated for the verification of the design of PAFS

  8. Separate-effect Test for Cooling Performance of PAFS(Passive Auxiliary Feedwater System)

    Energy Technology Data Exchange (ETDEWEB)

    Bae, Byoung Uhn; Kim, Seok; Kang, Kyung Ho; Yun, Byong Jo; Kim, Bok Duk [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2011-10-15

    APR+ (Advanced Power Reactor Plus) is a next generation nuclear power plant being developed in Korea. It adopts PAFS (Passive Auxiliary Feedwater System) for the steam generator (SG) instead of an active auxiliary feedwater system for the conventional nuclear power plant (NPP). It can replace the conventional active auxiliary feedwater system for the SG by a passive way. It is composed of a steam-supply line, a condensation heat exchanger, a return-water line, and a PCCT (Passive Condensate Cooling Tank). When the water level in the SG becomes lower than 25% of the wide range of the water level transmitter during an accident situation, the actuation valve at the return-water line is open and then the natural convection flow of the PAFS can be made. To validate a cooling performance of PAFS, separate effect test loop, which is named PASCAL (PAFS Condensing heat removal Assessment Loop) was constructed at KAERI (Korea Atomic Energy Research Institute) for investigating the cooling capability of the condensation heat exchanger and the characteristic of the natural convection. This study focuses on the experimental study of the separate effect test with PASCAL facility. From the experimental results, two-phase flow phenomena in the condensation heat exchanger and PCCT are investigated for the verification of the design of PAFS

  9. NSTS Orbiter auxiliary power unit turbine wheel cracking risk assessment

    Science.gov (United States)

    Cruse, T. A.; Mcclung, R. C.; Torng, T. Y.

    1992-01-01

    The present investigation of turbine-wheel cracking problems in the hydrazine-fueled APU turbine wheel of the Space Shuttle Orbiter's Main Engines has indicated the efficacy of systematic probabilistic risk assessment in flight certification and safety resolution. Nevertheless, real crack-initiation and propagation problems do not lend themselves to purely analytical studies. The high-cycle fatigue problem is noted to generally be unsuited to probabilistic modeling, due to its extremely high degree of intrinsic scatter. In the case treated, the cracks appear to trend toward crack arrest in a low cycle fatigue mode, due to a detuning of the resonance model.

  10. The power of glove: Soft microbial fuel cell for low-power electronics

    Science.gov (United States)

    Winfield, Jonathan; Chambers, Lily D.; Stinchcombe, Andrew; Rossiter, Jonathan; Ieropoulos, Ioannis

    2014-03-01

    A novel, soft microbial fuel cell (MFC) has been constructed using the finger-piece of a standard laboratory natural rubber latex glove. The natural rubber serves as structural and proton exchange material whilst untreated carbon veil is used for the anode. A soft, conductive, synthetic latex cathode is developed that coats the outside of the glove. This inexpensive, lightweight reactor can without any external power supply, start up and energise a power management system (PMS), which steps-up the MFC output (0.06-0.17 V) to practical levels for operating electronic devices (>3 V). The MFC is able to operate for up to 4 days on just 2 mL of feedstock (synthetic tryptone yeast extract) without any cathode hydration. The MFC responds immediately to changes in fuel-type when the introduction of urine accelerates the cycling times (35 vs. 50 min for charge/discharge) of the MFC and PMS. Following starvation periods of up to 60 h at 0 mV the MFC is able to cold start the PMS simply with the addition of 2 mL fresh feedstock. These findings demonstrate that cheap MFCs can be developed as sole power sources and in conjunction with advancements in ultra-low power electronics, can practically operate small electrical devices.

  11. Temperature and Humidity Sensor Powered by an Individual Microbial Fuel Cell in a Power Management System

    Directory of Open Access Journals (Sweden)

    Qi Zheng

    2015-09-01

    Full Text Available Microbial fuel cells (MFCs are of increasing interest as bioelectrochemical systems for decomposing organic materials and converting chemical energy into electricity. The main challenge for this technology is that the low power and voltage of the devices restricts the use of MFCs in practical applications. In this paper, a power management system (PMS is developed to store the energy and export an increased voltage. The designed PMS successfully increases the low voltage generated by an individual MFC to a high potential of 5 V, capable of driving a wireless temperature and humidity sensor based on nRF24L01 data transmission modules. With the PMS, MFCs can intermittently power the sensor for data transmission to a remote receiver. It is concluded that even an individual MFC can supply the energy required to power the sensor and telemetry system with the designed PMS. The presented PMS can be widely used for unmanned environmental monitoring such as wild rivers, lakes, and adjacent water areas, and offers promise for further advances in MFC technology.

  12. Fuel-Cell Power Source Based on Onboard Rocket Propellants

    Science.gov (United States)

    Ganapathi, Gani; Narayan, Sri

    2010-01-01

    The use of onboard rocket propellants (dense liquids at room temperature) in place of conventional cryogenic fuel-cell reactants (hydrogen and oxygen) eliminates the mass penalties associated with cryocooling and boil-off. The high energy content and density of the rocket propellants will also require no additional chemical processing. For a 30-day mission on the Moon that requires a continuous 100 watts of power, the reactant mass and volume would be reduced by 15 and 50 percent, respectively, even without accounting for boiloff losses. The savings increase further with increasing transit times. A high-temperature, solid oxide, electrolyte-based fuel-cell configuration, that can rapidly combine rocket propellants - both monopropellant system with hydrazine and bi-propellant systems such as monomethyl hydrazine/ unsymmetrical dimethyl hydrazine (MMH/UDMH) and nitrogen tetroxide (NTO) to produce electrical energy - overcomes the severe drawbacks of earlier attempts in 1963-1967 of using fuel reforming and aqueous media. The electrical energy available from such a fuel cell operating at 60-percent efficiency is estimated to be 1,500 Wh/kg of reactants. The proposed use of zirconia-based oxide electrolyte at 800-1,000 C will permit continuous operation, very high power densities, and substantially increased efficiency of conversion over any of the earlier attempts. The solid oxide fuel cell is also tolerant to a wide range of environmental temperatures. Such a system is built for easy refueling for exploration missions and for the ability to turn on after several years of transit. Specific examples of future missions are in-situ landers on Europa and Titan that will face extreme radiation and temperature environments, flyby missions to Saturn, and landed missions on the Moon with 14 day/night cycles.

  13. The Business Case for Fuel Cells 2012. America's Partner in Power

    Energy Technology Data Exchange (ETDEWEB)

    Curtin, Sandra [Fuel Cells 2000, Washington, DC (United States); Gangi, Jennifer [Fuel Cells 2000, Washington, DC (United States); Skukowski, Ryan [Fuel Cells 2000, Washington, DC (United States)

    2012-12-01

    This report, compiled by Fuel Cells 2000 with support from the Fuel Cell Technologies Program, profiles a select group of nationally recognizable companies and corporations that are deploying or demonstrating fuel cells. These businesses are taking advantage of a fuel cell's unique benefits, especially for powering lift trucks and providing combined heat and power to their stores and administrative offices.

  14. Energy management of fuel cell/solar cell/supercapacitor hybrid power source

    Energy Technology Data Exchange (ETDEWEB)

    Thounthong, Phatiphat; Sethakul, Panarit [Department of Teacher Training in Electrical Engineering, King Mongkut' s University of Technology North Bangkok, 1518, Piboolsongkram Road, Bangsue, Bangkok 10800 (Thailand); Chunkag, Viboon [Department of Electrical Engineering, King Mongkut' s University of Technology North Bangkok, 1518, Piboolsongkram Road, Bangsue, Bangkok 10800 (Thailand); Sikkabut, Suwat [Thai-French Innovation Institute, King Mongkut' s University of Technology North Bangkok, 1518, Piboolsongkram Road, Bangsue, Bangkok 10800 (Thailand); Pierfederici, Serge; Davat, Bernard [Groupe de Recherche en Electrotechnique et Electronique de Nancy (GREEN: UMR 7037), Nancy Universite, INPL-ENSEM, 2, Avenue de la Foret de Haye, Vandoeuvre-les-Nancy, Lorraine 54516 (France)

    2011-01-01

    This study presents an original control algorithm for a hybrid energy system with a renewable energy source, namely, a polymer electrolyte membrane fuel cell (PEMFC) and a photovoltaic (PV) array. A single storage device, i.e., a supercapacitor (ultracapacitor) module, is in the proposed structure. The main weak point of fuel cells (FCs) is slow dynamics because the power slope is limited to prevent fuel starvation problems, improve performance and increase lifetime. The very fast power response and high specific power of a supercapacitor complements the slower power output of the main source to produce the compatibility and performance characteristics needed in a load. The energy in the system is balanced by d.c.-bus energy regulation (or indirect voltage regulation). A supercapacitor module functions by supplying energy to regulate the d.c.-bus energy. The fuel cell, as a slow dynamic source in this system, supplies energy to the supercapacitor module in order to keep it charged. The photovoltaic array assists the fuel cell during daytime. To verify the proposed principle, a hardware system is realized with analog circuits for the fuel cell, solar cell and supercapacitor current control loops, and with numerical calculation (dSPACE) for the energy control loops. Experimental results with small-scale devices, namely, a PEMFC (1200 W, 46 A) manufactured by the Ballard Power System Company, a photovoltaic array (800 W, 31 A) manufactured by the Ekarat Solar Company and a supercapacitor module (100 F, 32 V) manufactured by the Maxwell Technologies Company, illustrate the excellent energy-management scheme during load cycles. (author)

  15. Nonlinear observer designs for fuel cell power systems

    Science.gov (United States)

    Gorgun, Haluk

    A fuel cell is an electrochemical device that combines hydrogen and oxygen, with the aid of electro-catalysts, to produce electricity. A fuel cell consists of a negatively charged anode, a positively charged cathode and an electrolyte, which transports protons or ions. A low temperature fuel cell has an electrical potential of about 0.7 Volt when generating a current density of 300--500 mA/cm2. Practical fuel cell power systems will require a combination of several cells in series (a stack) to satisfy the voltage requirements of specific applications. Fuel cells are suitable for a potentially wide variety of applications, from stationary power generation in the range of hundreds of megawatts to portable electronics in the range of a couple of watts. Efficient operation of a fuel cell system requires advanced feedback control designs. Reliable measurements from the system are necessary to implement such designs. However, most of the commercially available sensors do not operate properly in the reformate and humidified gas streams in fuel cell systems. Sensors working varying degrees of success are too big and costly, and sensors that are potentially low cost are not reliable or do not have the required life time [28]. Observer designs would eliminate sensor needs for measurements, and make feedback control implementable. Since the fuel cell system dynamics are highly nonlinear, observer design is not an easy task. In this study we aim to develop nonlinear observer design methods applicable to fuel cell systems. In part I of the thesis we design an observer to estimate the hydrogen partial pressure in the anode channel. We treat inlet partial pressure as an unknown slowly varying parameter and develop an adaptive observer that employs a nonlinear voltage injection term. However in this design Fuel Processing System (FPS) dynamics are not modelled, and their effect on the anode dynamics are treated as plant uncertainty. In part II of the thesis we study the FPS

  16. Exergetic and exergoeconomic evaluation of a solid-oxide fuel-cell-based combined heat and power generation system

    International Nuclear Information System (INIS)

    Highlights: • Exergy-based evaluations of a SOFC-based power generation system have been made. • The exergy of fuel and the exergy of product are rigorously defined. • Cost balance and auxiliary equations are formulated for the exergoeconomic analysis. • The cost structure of the overall system has been analyzed. • Suggestions are made for improving the cost effectiveness of the entire system. - Abstract: Exergetic and exergoeconomic evaluations have been carried out for a 100 kW-class solid-oxide fuel-cell-based combined heat and power generation system, to find out the measures that would improve its efficiency, and, more importantly, its cost effectiveness. The exergoeconomic analysis is an appropriate combination of an exergetic analysis and an economic analysis; through exergoeconomics, we obtain the real cost associated with each stream and with the inefficiencies within each component in a system. For the analyses, the exergies of fuel and the exergies of product for all components have been defined. Subsequently, the exergetic efficiency of each component has been evaluated. By combining the results obtained from an economic analysis with the results of the exergetic analysis, the cost structure of the overall system has been figured out. The components, showing higher exergoeconomic factors such as SOFC stack, fuel blower, heat recovery water pump, and inverter, need reduction of investment cost, even if the associated efficiency would decreased because of this cost reduction. For the components, exhibiting lower exergoeconomic factors such as integrated reformer, fuel/water pre-heater, and air pre-heater, the main focus should be on efficiency improvements, even if higher investment expenditures would be associated with such improvements

  17. Copper anode corrosion affects power generation in microbial fuel cells

    KAUST Repository

    Zhu, Xiuping

    2013-07-16

    Non-corrosive, carbon-based materials are usually used as anodes in microbial fuel cells (MFCs). In some cases, however, metals have been used that can corrode (e.g. copper) or that are corrosion resistant (e.g. stainless steel, SS). Corrosion could increase current through galvanic (abiotic) current production or by increasing exposed surface area, or decrease current due to generation of toxic products from corrosion. In order to directly examine the effects of using corrodible metal anodes, MFCs with Cu were compared with reactors using SS and carbon cloth anodes. MFCs with Cu anodes initially showed high current generation similar to abiotic controls, but subsequently they produced little power (2 mW m-2). Higher power was produced with microbes using SS (12 mW m-2) or carbon cloth (880 mW m-2) anodes, with no power generated by abiotic controls. These results demonstrate that copper is an unsuitable anode material, due to corrosion and likely copper toxicity to microorganisms. © 2013 Society of Chemical Industry.

  18. Aging assessment of auxiliary feedwater pumps

    International Nuclear Information System (INIS)

    ORNL is conducting aging assessments of auxiliary feedwater pumps to provide recommendations for monitoring and assessing the severity of time-dependent degradation as well as to recommend maintenance and replacement practices. Cornerstones of these activities are the identification of failure modes and causes and ranking of causes. Failure modes and causes of interest are those due to aging and service wear. Design details, functional requirements, and operating experience data were used to identify failure modes and causes and to rank the latter. Based on this input, potentially useful inspection, surveillance, and condition monitoring methods that are currently available for use or in the developmental stage were examined and recommendations made. The methods selected are listed and discussed in terms of use and information to be obtained. Relationships between inspection, surveillance, and monitoring and maintenance practices entered prominently into maintenance recommendations. These recommendations, therefore, embrace predictive as well as corrective and preventative maintenance practices. The recommendations are described, inspection details are discussed, and periodic inspection and maintenance interval guidelines are given. Surveillance testing at low-flow conditions is also discussed. It is shown that this type of testing can lead to accelerated aging

  19. Continual Energy Management System of Proton Exchange Membrane Fuel Cell Hybrid Power Electric Vehicles

    OpenAIRE

    Ren Yuan; Zhong Zhi Dan; Zhang Zhi Wen; Luo Tian Yu

    2016-01-01

    Current research status in energy management of Proton Exchange Membrane (PEM) fuel cell hybrid power electric vehicles are first described in this paper, and then build the PEMFC/ lithium-ion battery/ ultra-capacitor hybrid system model. The paper analysis the key factors of the continuous power available in PEM fuel cell hybrid power electric vehicle and hybrid power system working status under different driving modes. In the end this paper gives the working flow chart of the hybrid power s...

  20. NaBH4 (sodium borohydride) hydrogen generator with a volume-exchange fuel tank for small unmanned aerial vehicles powered by a PEM (proton exchange membrane) fuel cell

    International Nuclear Information System (INIS)

    A proton exchange membrane fuel cell system integrated with a NaBH4 (sodium borohydride) hydrogen generator was developed for small UAVs (unmanned aerial vehicles). The hydrogen generator was composed of a catalytic reactor, liquid pump and volume-exchange fuel tank, where the fuel and spent fuel exchange the volume within a single fuel tank. Co–B catalyst supported on a porous ceramic material was used to generate hydrogen from the NaBH4 solution. Considering the power consumption according to the mission profile of a UAV, the power output of the fuel cell and auxiliary battery was distributed passively as an electrical load. A blended wing-body was selected considering the fuel efficiency and carrying capability of fuel cell components. First, the fuel cell stack and hydrogen generator were evaluated under the operating conditions, and integrated into the airframe. The ground test of the complete fuel cell UAV was performed under a range of load conditions. Finally, the fuel cell powered flight test was made for 1 h. The volume-exchange fuel tank minimized the fuel sloshing and the change in center of gravity due to fuel consumption during the flight, so that much stable operation of the fuel cell system was validated at different flight modes. - Highlights: • PEMFC system with a NaBH4 hydrogen source was developed for small UAVs. • Volume-exchange fuel tank was used to reduce the size of the fuel cell system. • Passive power management was used for a stable power output during the flight. • BWB UAV was selected by taking the fuel cell integration into consideration. • Stable operation of the fuel cell system was verified from the flight test

  1. Efficient Cells Cut the Cost of Solar Power

    Science.gov (United States)

    2013-01-01

    If you visit Glenn Research Center, you might encounter a photovoltaic (PV) array that looks unlike anything you've ever seen. In fact, what one would normally identify as the panel is actually a series of curved mirrors called solar concentrators, engineered to reflect sunlight rather than absorb it. These concentrators gather, intensify, and focus sun beams upward, aiming at a fixture containing specialized silicon concentrated PV chips the actual solar cells. If you stay by the array for a while, you'll notice that the solar concentrators follow the path of the sun throughout the day, changing position to best capture and utilize the sunlight. The specialized chips that make the technology possible are the brainchild of Bernard Sater, an engineer who had worked at Glenn since the early 1960s before retiring to pursue his unique ideas for harnessing solar power. Sater contributed to multiple PV projects in the latter part of his career at the Center, including research and development on the International Space Station s solar arrays. In his spare time, he enjoyed tinkering with new approaches to solar power, experiments that resulted in the system installed at Glenn today. Sater s basic idea had two components. First, he wanted to create a silicon cell that was smaller, more efficient, and much lower cost than those available at the time. To ensure that the potential of such a chip could be realized, he also planned on pairing it with a system that could concentrate sunlight and focus it directly on the cell. When he retired from Glenn in 1994 to focus on researching and developing the technology full time, Sater found that NASA was interested in the concept and ready to provide funding, facilities, and expertise in order to assist in its development.

  2. Auxiliary signal processing system for a multiparameter radar

    Science.gov (United States)

    Chandrasekar, V.; Gray, G. R.; Caylor, I. J.

    1993-01-01

    The design of an auxiliary signal processor for a multiparameter radar is described with emphasis on low cost, quick development, and minimum disruption of radar operations. The processor is based around a low-cost digital signal processor card and personal computer controller. With the use of such a concept, an auxiliary processor was implemented for the NCAR CP-2 radar during a 1991 summer field campaign and allowed measurement of additional polarimetric parameters, namely, the differential phase and the copolar cross correlation. Sample data are presented from both the auxiliary and existing radar signal processors.

  3. Syntactic Analyses for Parallel Grammars Auxiliaries and Genitive NPs

    CERN Document Server

    Butt, M; Rohrer, C; Butt, Miriaam; Fortman, Christian; Rohrer, Christian

    1996-01-01

    This paper focuses on two disparate aspects of German syntax from the perspective of parallel grammar development. As part of a cooperative project, we present an innovative approach to auxiliaries and multiple genitive NPs in German. The LFG-based implementation presented here avoids unnessary structural complexity in the representation of auxiliaries by challenging the traditional analysis of auxiliaries as raising verbs. The approach developed for multiple genitive NPs provides a more abstract, language independent representation of genitives associated with nominalized verbs. Taken together, the two approaches represent a step towards providing uniformly applicable treatments for differing languages, thus lightening the burden for machine translation.

  4. A Low-Power and Low-Voltage Power Management Strategy for On-Chip Micro Solar Cells

    Directory of Open Access Journals (Sweden)

    Ismail Cevik

    2015-01-01

    Full Text Available Fundamental characteristics of on-chip micro solar cell (MSC structures were investigated in this study. Several MSC structures using different layers in three different CMOS processes were designed and fabricated. Effects of PN junction structure and process technology on solar cell performance were measured. Parameters for low-power and low-voltage implementation of power management strategy and boost converter based circuits utilizing fractional voltage maximum power point tracking (FVMPPT algorithm were determined. The FVMPPT algorithm works based on the fraction between the maximum power point operation voltage and the open circuit voltage of the solar cell structure. This ratio is typically between 0.72 and 0.78 for commercially available poly crystalline silicon solar cells that produce several watts of power under typical daylight illumination. Measurements showed that the fractional voltage ratio is much higher and fairly constant between 0.82 and 0.85 for on-chip mono crystalline silicon micro solar cell structures that produce micro watts of power. Mono crystalline silicon solar cell structures were observed to result in better power fill factor (PFF that is higher than 74% indicating a higher energy harvesting efficiency.

  5. Salient aspects on the choice of classs 3 system - the diesel generating sets - engine, auxiliaries (Paper No. 2.5)

    International Nuclear Information System (INIS)

    The class 3 system is a basic requirement in all nuclear installations. Selection of this major equipment and associated auxiliaries plays an important role in the overall performance and reliability of the whole system. This paper deals with various sub-systems of class 3 power like engine, alternator, auxiliaries. It deals with method of arriving at capacity of sets based on connected loads, starting requirement and choice of engine based on site conditions, fuel used, duty, speed, mean effective pressures, typical layout of set and auxiliaries with its various sub-systems. Various engine starting methods, advantages and disadvantages, area requirements, choice of foundation, general guidlines for installation, testing and commissioning of medium size plant will be discussed in reference to applicable codes and practices. (author). 3 refs., 1 fig

  6. The development of a passive auxiliary feedwater system in APR+

    International Nuclear Information System (INIS)

    The Advanced Power Reactor Plus (APR+) is being developed in Korea. APR+ is a GEN III+ reactor on the basis of the APR1400. To meet the requirements of GEN III+ reactors, the economics and the safety of the APR+ are further enhanced. One of the basic principles of APR+ safety systems is the adoption of hybrid safety systems. Passive safety systems replace the current active safety systems from an economic point of view. The passive aux. feedwater system (PAFS) is one of the passive safety features adopted in the APR+. The PAFS replaces the conventional active auxiliary feedwater system by introducing a natural driving force mechanism while maintaining the system's basic Junction of cooling down the primary side and removing the decay heat. In order to satisfy the single failure criterion, the PAFS is composed of two independent trains. Each train has one steam condensing heat exchanger of 100% capability and one PCCT (Passive Condensation Cooling water Tank) of 100% capability. Basic design is underway and separate effect tests and integral effect tests will be performed to demonstrate the performance of the PAFS. (authors)

  7. A Study of the Disturbance in Steam Power Unit Caused by Solar Auxiliary Heating System%太阳能辅助加热系统对蒸汽动力机组运行性能的扰动研究

    Institute of Scientific and Technical Information of China (English)

    安连锁; 徐玫; 陈海平; 冯蕾; 张衡

    2015-01-01

    It is common that variable conditions are considered in the process of solar-assisted coal-fired power system designing. Small disturbance theory tells us that when no obvious water distribution happens complex variable conditions calculation can be saved and the results which meet required precision can be achieved as well. A quantitative analysis was conducted for the impact of the solar auxiliary heating system on the thermal system. The results show that within a small range the impact caused by the solar auxiliary heating system can be regarded as a small disturbance, while in the usual range(30% to 100%) although it can not be regarded as a small disturbance the calculation of steam admission flow and power generation can be simplfied under the coal-saving and power-boosting operation mode. In addition, the calculation of thermal conversion rate, generating heat rate and coal consumption rate can be simplified when the percentage of replacing point 1 extraction steam is under 60%; the calculation of thermal conversion rate, generating heat rate, coal consumption rate in waste heat utilization can be simplified no matter how the percentage of replacing extraction steam changes; the calculation of collector field area and the initial investment can also be simplified when the percentage of replacing point 1 extraction steam is under 55%. That is, the error of the caculation for the above parameters meet the engineering accuracy requirement when small disturbance algorithm is used. The above conclusion provides a theoretical reference for the optimal design and analysis of the solar-aided coal-fired power system.%光煤互补热发电系统的设计过程中通常都要进行变工况计算,由小扰动理论可知,当系统变动不足以引起汽水重新分布时,省去繁杂的变工况计算也可得到精度合乎要求的结果。该文针对太阳能辅助加热系统对热力系统影响进行了定量分析,结果表明太阳能辅助加热系

  8. Environmental impact assessment of the incineration of municipal solid waste with auxiliary coal in China

    DEFF Research Database (Denmark)

    Zhao, Yan; Xing, Wei; Lu, Wenjing;

    2012-01-01

    mitigating global warming, whereas incineration with a mass of coal can avoid more impacts to acidification, photochemical ozone and nutrient enrichment because of increased electricity substitution and reduced emission from coal power plants. The “Emission standard of air pollutants for thermal power plants...... political reduction targets. Results indicate that heavy metal and acidic gas emissions should be given more attention in waste incineration. This study provides scientific support for the management of MSW systems dominated by incineration with auxiliary coal in China....

  9. Solid Oxide Fuel Cell/Turbine Hybrid Power System for Advanced Aero-propulsion and Power Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Solid oxide fuel cell (SOFC)/ gas turbine hybrid power systems (HPSs) have been recognized by federal agencies and other entities as having the potential to operate...

  10. Modeling and Nonlinear Control of Electric Power Stage in Hybrid Electric Vehicle

    OpenAIRE

    A. TAHRI; El Fadil, H.; Guerrero, Josep M.; Giri, F.; Chaoui, F. Z.

    2014-01-01

    This paper deals with the problem of modeling and controlling the electric power stage of hybrid electric vehicle. The controlled system consists of a fuel cell (FC) as a main source, a supercapacitor as an auxiliary source, two DC-DC power converters, an inverter and a traction induction motor. The proposed strategy involves a multi-loop nonlinear controller designed to meet the three main control objectives: (i) a tight speed regulation in spite of torque load variations. (ii) a good regula...

  11. 46 CFR 182.620 - Auxiliary means of steering.

    Science.gov (United States)

    2010-10-01

    ... TONS) MACHINERY INSTALLATION Steering Systems § 182.620 Auxiliary means of steering. (a) Except as... personnel hazards during normal or heavy weather operation. (b) A suitable hand tiller may be acceptable...

  12. Power generation from furfural using the microbial fuel cell

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Yong; Liu, Guangli; Zhang, Renduo; Zhang, Cuiping [School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou, Guangdong 510275 (China)

    2010-01-01

    Furfural is a typical inhibitor in the ethanol fermentation process using lignocellulosic hydrolysates as raw materials. In the literature, no report has shown that furfural can be utilized as the fuel to produce electricity in the microbial fuel cell (MFC), a device that uses microbes to convert organic compounds to generate electricity. In this study, we demonstrated that electricity was successfully generated using furfural as the sole fuel in both the ferricyanide-cathode MFC and the air-cathode MFC. In the ferricyanide-cathode MFC, the maximum power densities reached 45.4, 81.4, and 103 W m{sup -3}, respectively, when 1000 mg L{sup -1} glucose, a mixture of 200 mg L{sup -1} glucose and 5 mM furfural, and 6.68 mM furfural were used as the fuels in the anode solution. The corresponding Coulombic efficiencies (CE) were 4.0, 7.1, and 10.2% for the three treatments, respectively. For pure furfural as the fuel, the removal efficiency of furfural reached up to 95% within 12 h. In the air-cathode MFC using 6.68 mM furfural as the fuel, the maximum values of power density and CE were 361 mW m{sup -2} (18 W m{sup -3}) and 30.3%, respectively, and the COD removal was about 68% at the end of the experiment (about 30 h). Increase in furfural concentrations from 6.68 to 20 mM resulted in increase in the maximum power densities from 361 to 368 mW m{sup -2}, and decrease in CEs from 30.3 to 20.6%. These results indicated that some toxic and biorefractory organics such as furfural might still be suitable resources for electricity generation using the MFC technology. (author)

  13. Direct fuel cell power plants: the final steps to commercialization

    Science.gov (United States)

    Glenn, Donald R.

    Since the last paper presented at the Second Grove Fuel Cell Symposium, the Energy Research Corporation (ERC) has established two commercial subsidiaries, become a publically-held firm, expanded its facilities and has moved the direct fuel cell (DFC) technology and systems significantly closer to commercial readiness. The subsidiaries, the Fuel Cell Engineering Corporation (FCE) and Fuel Cell Manufacturing Corporation (FCMC) are perfecting their respective roles in the company's strategy to commercialize its DFC technology. FCE is the prime contractor for the Santa Clara Demonstration and is establishing the needed marketing, sales, engineering, and servicing functions. FCMC in addition to producing the stacks and stack modules for the Santa Clara demonstration plant is now upgrading its production capability and product yields, and retooling for the final stack scale-up for the commercial unit. ERC has built and operated the tallest and largest capacities-to-date carbonate fuel cell stacks as well as numerous short stacks. While most of these units were tested at ERC's Danbury, Connecticut (USA) R&D Center, others have been evaluated at other domestic and overseas facilities using a variety of fuels. ERC has supplied stacks to Elkraft and MTU for tests with natural gas, and RWE in Germany where coal-derived gas were used. Additional stack test activities have been performed by MELCO and Sanyo in Japan. Information from some of these activities is protected by ERC's license arrangements with these firms. However, permission for limited data releases will be requested to provide the Grove Conference with up-to-date results. Arguably the most dramatic demonstration of carbonate fuel cells in the utility-scale, 2 MW power plant demonstration unit, located in the City of Santa Clara, California. Construction of the unit's balance-of-plant (BOP) has been completed and the installed equipment has been operationally checked. Two of the four DFC stack sub-modules, each

  14. Bayesian auxiliary variable models for binary and multinomial regression

    OpenAIRE

    Holmes, C C; HELD, L.

    2006-01-01

    In this paper we discuss auxiliary variable approaches to Bayesian binary and multinomial regression. These approaches are ideally suited to automated Markov chain Monte Carlo simulation. In the first part we describe a simple technique using joint updating that improves the performance of the conventional probit regression algorithm. In the second part we discuss auxiliary variable methods for inference in Bayesian logistic regression, including covariate set uncertainty. Fina...

  15. Operating experiences and degradation detection for auxiliary feedwater systems

    International Nuclear Information System (INIS)

    A study of Pressurized Water Reactor Auxiliary Feedwater (AFW) Systems has been conducted by Oak Ridge National Laboratory (ORNL) under the auspices of the Nuclear Regulatory Commission's Nuclear Plant Aging Research Program. The results of the study are documented in NUREG/CR-5404, Vol. 1, Auxiliary Feedwater System Aging Study. The study reviewed historical failure experience and current monitoring practices for the AFW System. This paper provides an overview of the study approach and results

  16. New braneworld models in the presence of auxiliary fields

    CERN Document Server

    Bazeia, D; Menezes, R; Moreira, D C

    2014-01-01

    We study braneworld models in the presence of auxiliary fields. We use the first-order framework to investigate several distinct possibilities, where the standard braneworld scenario changes under the presence of the parameter that controls the auxiliary fields introduced to modify Einstein's equation. The results add to previous ones, to show that the minimal modification that we investigate contributes to change quantitatively the thick braneworld profile, although no new qualitative effect is capable of being induced by the minimal modification here considered.

  17. Alphabet Sizes of Auxiliary Variables in Canonical Inner Bounds

    OpenAIRE

    Jana, Soumya

    2008-01-01

    Alphabet size of auxiliary random variables in our canonical description is derived. Our analysis improves upon estimates known in special cases, and generalizes to an arbitrary multiterminal setup. The salient steps include decomposition of constituent rate polytopes into orthants, translation of a hyperplane till it becomes tangent to the achievable region at an extreme point, and derivation of minimum auxiliary alphabet sizes based on Caratheodory's theorem.

  18. Soft switching DC/DC converter using auxiliary circuits

    OpenAIRE

    Jaroslav Dudrik; Vladimír Ruščin

    2008-01-01

    A novel auxiliary circuit for full-bridge PWMDC/DC converter with controlled secondary side rectifieris presented in this paper. Zero-current turn-on for allpower switches of the inverter is achieved for full loadrange from no-load to short circuit by using controlledrectifier and auxiliary circuit on the secondary side.Modified phase shift PWM control strategy is used for theconverter. The principle of operation is explained andanalyzed and the simulation results are presented.

  19. Proton irradiation effects of amorphous silicon solar cell for solar power satellite

    Energy Technology Data Exchange (ETDEWEB)

    Morita, Yousuke; Oshima, Takeshi [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment; Sasaki, Susumu; Kuroda, Hideo; Ushirokawa, Akio

    1997-03-01

    Flexible amorphous silicon(fa-Si) solar cell module, a thin film type, is regarded as a realistic power generator for solar power satellite. The radiation resistance of fa-Si cells was investigated by the irradiations of 3,4 and 10 MeV protons. The hydrogen gas treatment of the irradiated fa-Si cells was also studied. The fa-Si cell shows high radiation resistance for proton irradiations, compared with a crystalline silicon solar cell. (author)

  20. Lithium Dinitramide as an Additive in Lithium Power Cells

    Science.gov (United States)

    Gorkovenko, Alexander A.

    2007-01-01

    Lithium dinitramide, LiN(NO2)2 has shown promise as an additive to nonaqueous electrolytes in rechargeable and non-rechargeable lithium-ion-based electrochemical power cells. Such non-aqueous electrolytes consist of lithium salts dissolved in mixtures of organic ethers, esters, carbonates, or acetals. The benefits of adding lithium dinitramide (which is also a lithium salt) include lower irreversible loss of capacity on the first charge/discharge cycle, higher cycle life, lower self-discharge, greater flexibility in selection of electrolyte solvents, and greater charge capacity. The need for a suitable electrolyte additive arises as follows: The metallic lithium in the anode of a lithium-ion-based power cell is so highly reactive that in addition to the desired main electrochemical reaction, it engages in side reactions that cause formation of resistive films and dendrites, which degrade performance as quantified in terms of charge capacity, cycle life, shelf life, first-cycle irreversible capacity loss, specific power, and specific energy. The incidence of side reactions can be reduced through the formation of a solid-electrolyte interface (SEI) a thin film that prevents direct contact between the lithium anode material and the electrolyte. Ideally, an SEI should chemically protect the anode and the electrolyte from each other while exhibiting high conductivity for lithium ions and little or no conductivity for electrons. A suitable additive can act as an SEI promoter. Heretofore, most SEI promotion was thought to derive from organic molecules in electrolyte solutions. In contrast, lithium dinitramide is inorganic. Dinitramide compounds are known as oxidizers in rocket-fuel chemistry and until now, were not known as SEI promoters in battery chemistry. Although the exact reason for the improvement afforded by the addition of lithium dinitramide is not clear, it has been hypothesized that lithium dinitramide competes with other electrolyte constituents to react with

  1. Placement of Combined Heat, Power and Hydrogen Production Fuel Cell Power Plants in a Distribution Network

    Directory of Open Access Journals (Sweden)

    Bahman Bahmanifirouzi

    2012-03-01

    Full Text Available This paper presents a new Fuzzy Adaptive Modified Particle Swarm Optimization algorithm (FAMPSO for the placement of Fuel Cell Power Plants (FCPPs in distribution systems. FCPPs, as Distributed Generation (DG units, can be considered as Combined sources of Heat, Power, and Hydrogen (CHPH. CHPH operation of FCPPs can improve overall system efficiency, as well as produce hydrogen which can be stored for the future use of FCPPs or can be sold for profit. The objective functions investigated are minimizing the operating costs of electrical energy generation of distribution substations and FCPPs, minimizing the voltage deviation and minimizing the total emission. In this regard, this paper just considers the placement of CHPH FCPPs while investment cost of devices is not considered. Considering the fact that the objectives are different, non-commensurable and nonlinear, it is difficult to solve the problem using conventional approaches that may optimize a single objective. Moreover, the placement of FCPPs in distribution systems is a mixed integer problem. Therefore, this paper uses the FAMPSO algorithm to overcome these problems. For solving the proposed multi-objective problem, this paper utilizes the Pareto Optimality idea to obtain a set of solution in the multi-objective problem instead of only one. Also, a fuzzy system is used to tune parameters of FAMPSO algorithm such as inertia weight. The efficacy of the proposed approach is validated on a 69-bus distribution system.

  2. External magnetic field effect on bifacial silicon solar cell''s electric power and conversion efficiencyExternal magnetic field effect on bifacial silicon solar cell''s electric power and conversion efficiency

    OpenAIRE

    ZERBO, ISSA; ZOUNGRANA, MARTIAL; SOURABIE, IDRISSA; Ouedraogo, Adama; ZOUMA, BERNARD; BATHIEBO, DIEUDONNE JOSEPH

    2015-01-01

    This article presents a modelling study of external magnetic field effect on a bifacial silicon solar cell's electric power and conversion efficiency. After the resolution of the magnetotransport equation and continuity equation of excess minority carriers, we calculate the photocurrent density and the photovoltage and then we deduce the solar cell's electric power before discussing the influence of the magnetic field on those electrical parameters. Using the electric power curves...

  3. Characterization of high performance silicon-based VMJ PV cells for laser power transmission applications

    Science.gov (United States)

    Perales, Mico; Yang, Mei-huan; Wu, Cheng-liang; Hsu, Chin-wei; Chao, Wei-sheng; Chen, Kun-hsien; Zahuranec, Terry

    2016-03-01

    Continuing improvements in the cost and power of laser diodes have been critical in launching the emerging fields of power over fiber (PoF), and laser power beaming. Laser power is transmitted either over fiber (for PoF), or through free space (power beaming), and is converted to electricity by photovoltaic cells designed to efficiently convert the laser light. MH GoPower's vertical multi-junction (VMJ) PV cell, designed for high intensity photovoltaic applications, is fueling the emergence of this market, by enabling unparalleled photovoltaic receiver flexibility in voltage, cell size, and power output. Our research examined the use of the VMJ PV cell for laser power transmission applications. We fully characterized the performance of the VMJ PV cell under various laser conditions, including multiple near IR wavelengths and light intensities up to tens of watts per cm2. Results indicated VMJ PV cell efficiency over 40% for 9xx nm wavelengths, at laser power densities near 30 W/cm2. We also investigated the impact of the physical dimensions (length, width, and height) of the VMJ PV cell on its performance, showing similarly high performance across a wide range of cell dimensions. We then evaluated the VMJ PV cell performance within the power over fiber application, examining the cell's effectiveness in receiver packages that deliver target voltage, intensity, and power levels. By designing and characterizing multiple receivers, we illustrated techniques for packaging the VMJ PV cell for achieving high performance (> 30%), high power (> 185 W), and target voltages for power over fiber applications.

  4. Conceptual design of the integral test loop (II) : Safety system and auxiliary system

    Energy Technology Data Exchange (ETDEWEB)

    Park, Choon Kyung; Song, Chul Hwa; Choi, Byeong Hae; Chung Moon Ki [Korea Atomic Energy Research Institute, Taejon (Korea)

    1999-10-01

    This report describes the results of the conceptual design work on the safety system and auxiliary system of the Integral Test Loop (ITL) which simulates overall thermal hydraulic phenomena of the primary system of a nuclear power plant during postulated accidents or transients. The design basis for the safety and auxiliary systems is the same as that applied to the primary and secondary systems of the ITL as follows ; Reference plant : Korean Standard Nuclear Plant (KSNP), Height ratio :1/1, Volume ration: 1/200, Temperature, Pressure : Real plant conditions, The safety system contains a safety depressurization system (SDS) and a safety injection system (SIS). And the auxiliary system comprises a containment system, a shutdown cooling system (SCS), a volume control system (VCS), a makeup water system and a component cooling water system (CCWS). This conceptual design report describes the configurations and operation of the systems of the reference plant, and also describes the design philosophy of the corresponding components and systems of the ITL. In addition, this report specifies the design criteria and technical specifications of each component and system of the ITL. 6 refs., 11 figs., 21 tabs. (Author)

  5. Trace analysis of auxiliary feedwater capacity for Maanshan PWR loss-of-normal-feedwater transient

    International Nuclear Information System (INIS)

    Maanshan nuclear power plant is a Westinghouse PWR of Taiwan Power Company (Taipower, TPC). A few years ago, TPC has made many assessments in order to uprate the power of Maanshan NPP. The assessments include NSSS (Nuclear Steam Supply System) parameters calculation, uncertainty acceptance, integrity of pressure vessel, reliability of auxiliary systems, and transient analyses, etc. Since the Fukushima Daiichi accident happened, it is necessary to consider transients with multiple-failure. Base on the analysis, we further study the auxiliary feedwater capability for Loss-of-Normal-Feedwater (LONF) transient. LONF is the limiting transient of non-turbine trip initiated event for ATWS (Anticipated Transient Without Scram) which results in a reduction in capability of the secondary system to remove the heat generated in the reactor core. If the turbine fails to trip immediately, the secondary water inventory will decrease significantly before the actuation of auxiliary feedwater (AFW) system. The heat removal from the primary side decreases, and this leads to increases of primary coolant temperature and pressure. The water level of pressurizer also increases subsequently. The heat removal through the relief valves and the auxiliary feedwater is not sufficient to fully cope with the heat generation from primary side. The pressurizer will be filled with water finally, and the RCS pressure might rise above the set point of relief valves for water discharge. RCS pressure depends on steam generator inventory, primary coolant temperature, negative reactivity feedback, and core power, etc. The RCS pressure may reach its peak after core power reduction. According to ASME Code Level C service limit criteria, the Reactor Coolant System (RCS) pressure must be under 22.06 MPa. The USNRC is developing an advanced thermal hydraulic code named TRACE for nuclear power plant safety analysis. The development of TRACE is based on TRAC and integrating with RELAP5 and other programs. SNAP

  6. A PPS Sampling Scheme Using Harmonic Mean of An Auxiliary Variable

    OpenAIRE

    L.N. Sahoo; Dalabehera, M.; A.K. Mangaraj

    2012-01-01

    We consider a probability proportional to size sampling scheme by using harmonic mean of an auxiliary variable, when the correlation between study variable and auxiliary variable is highly negative. This is achieved by considering inverse transformation of the auxiliary variable and then utilizing the transformed auxiliary variable values at the design stage of the survey operation in selecting a sample.

  7. A microprocessor-based fuzzy logic control strategy for fuel cell powered bicycle

    International Nuclear Information System (INIS)

    This research is aimed to develop a fuzzy logic control strategy for fuel cell powered bicycle. Advanced control strategy with low cost microprocessor is a crucial development step for future commercialization phase of fuel cell system applications. In this paper, a micro controller based fuzzy logic control strategy and system is developed to improve the running performance of the bicycle, as the fuel cell powered system has great uncertainty of power output. Through advanced control methods, significant improvement in the performance of fuel cell powered bicycle, the energy consumption, and the running speed can be achieved. (author)

  8. High-performance radial AMTEC cell design for ultra-high-power solar AMTEC systems

    Energy Technology Data Exchange (ETDEWEB)

    Hendricks, T.J.; Huang, C.

    1999-07-01

    Alkali Metal Thermal to Electric Conversion (AMTEC) technology is rapidly maturing for potential application in ultra-high-power solar AMTEC systems required by potential future US Air Force (USAF) spacecraft missions in medium-earth and geosynchronous orbits (MEO and GEO). Solar thermal AMTEC power systems potentially have several important advantages over current solar photovoltaic power systems in ultra-high-power spacecraft applications for USAF MEO and GEO missions. This work presents key aspects of radial AMTEC cell design to achieve high cell performance in solar AMTEC systems delivering larger than 50 kW(e) to support high power USAF missions. These missions typically require AMTEC cell conversion efficiency larger than 25%. A sophisticated design parameter methodology is described and demonstrated which establishes optimum design parameters in any radial cell design to satisfy high-power mission requirements. Specific relationships, which are distinct functions of cell temperatures and pressures, define critical dependencies between key cell design parameters, particularly the impact of parasitic thermal losses on Beta Alumina Solid Electrolyte (BASE) area requirements, voltage, number of BASE tubes, and system power production for both maximum power-per-BASE-area and optimum efficiency conditions. Finally, some high-level system tradeoffs are demonstrated using the design parameter methodology to establish high-power radial cell design requirements and philosophy. The discussion highlights how to incorporate this methodology with sophisticated SINDA/FLUINT AMTEC cell modeling capabilities to determine optimum radial AMTEC cell designs.

  9. Organization and scheduling of auxiliary components and large equipments erection and control

    International Nuclear Information System (INIS)

    The first part of this paper deals with the installation of auxiliary systems. FRAMATOME divides NSSS site construction activities into the following 3 packages: main primary system, electricity and instrumentation and control, and auxiliary systems. This paper presents an analysis of the organisation of auxiliary system installation with particular reference to piping. The term ''auxiliary systems'' covers all NSSS mechanical and electrical equipment with the exception of heavy Reactor Coolant System components (reactor, fuel, associated handling equipment and cooling loops). FRAMATOME, with the help of its associates working on the French nuclear programme, has been able to develop efficient methods of organisation as a result of the wide experience gained. The main field involved is that of piping, for which computerized task analysis, scheduling and follow-up methods have been developed. The second part deals with large components installation. The normal sequence of welding operations for the assembly of the reactor coolant loops of a PWR power plant begins with the simultaneous welding of hot and cold leg piping and is completed by the welding of the crossover leg between the steam generator and the reactor coolant pump, thus ''closing'' the loop. This is the traditional method. FRAMATOME has developed a different method whereby installation of the reactor coolant loops begins with the welding of the steam generator - reactor coolant pump connection. This is the ''crossover leg'' method. This report presents a description of both methods followed by the results of a comparative study of technical considerations and schedules; in conclusion, charts are presented to assist in pre-selection of the method which is best suited to the on-site delivery schedule of Reactor Coolant System components

  10. VLTI First Fringes with Two Auxiliary Telescopes at Paranal

    Science.gov (United States)

    2005-03-01

    ESO Video Newsreel 15, released on March 14, 2005. It provides an introduction to the VLT Interferometer (VLTI) and the two Auxiliary Telescopes (ATs) now installed at Paranal. ESO PR Photo 07a/05 shows the impressive ensemble at the summit of Paranal. From left to right, the enclosure of VLT Antu, Kueyen and Melipal, AT1, the VLT Survey Telescope (VST) in the background, AT2 and VLT Yepun. Located at the summit of the 2,600-m high Cerro Paranal in the Atacama Desert (Chile), ESO's Very Large Telescope (VLT) is at the forefront of astronomical technology and is one of the premier facilities in the world for optical and near-infrared observations. The VLT is composed of four 8.2-m Unit Telescope (Antu, Kueyen, Melipal and Yepun). They have been progressively put into service together with a vast suite of the most advanced astronomical instruments and are operated every night in the year. Contrary to other large astronomical telescopes, the VLT was designed from the beginning with the use of interferometry as a major goal. The href="/instruments/vlti">VLT Interferometer (VLTI) combines starlight captured by two 8.2- VLT Unit Telescopes, dramatically increasing the spatial resolution and showing fine details of a large variety of celestial objects. The VLTI is arguably the world's most advanced optical device of this type. It has already demonstrated its powerful capabilities by addressing several key scientific issues, such as determining the size and the shape of a variety of stars (ESO PR 22/02, PR 14/03 and PR 31/03), measuring distances to stars (ESO PR 25/04), probing the innermost regions of the proto-planetary discs around young stars (ESO PR 27/04) or making the first detection by infrared interferometry of an extragalactic object (ESO PR 17/03). "Little Brothers" ESO PR Photo 07b/05 ESO PR Photo 07b/05 [Preview - JPEG: 597 x 400 pix - 47k] [Normal - JPEG: 1193 x 800 pix - 330k] [HiRes - JPEG: 5000 x 3354 pix - 10.0M] ESO PR Photo 07c/05 ESO PR Photo 07c/05

  11. Fuel Cell-Powered Lift Truck Fleet Deployment Projects Final Technical Report May 2014

    Energy Technology Data Exchange (ETDEWEB)

    Klingler, James J [GENCO Infrastructure Solutions, Inc.

    2014-05-06

    The overall objectives of this project were to evaluate the performance, operability and safety of fork lift trucks powered by fuel cells in large distribution centers. This was accomplished by replacing the batteries in over 350 lift trucks with fuel cells at five distribution centers operated by GENCO. The annual cost savings of lift trucks powered by fuel cell power units was between $2,400 and $5,300 per truck compared to battery powered lift trucks, excluding DOE contributions. The greatest savings were in fueling labor costs where a fuel cell powered lift truck could be fueled in a few minutes per day compared to over an hour for battery powered lift trucks which required removal and replacement of batteries. Lift truck operators where generally very satisfied with the performance of the fuel cell power units, primarily because there was no reduction in power over the duration of a shift as experienced with battery powered lift trucks. The operators also appreciated the fast and easy fueling compared to the effort and potential risk of injury associated with switching heavy batteries in and out of lift trucks. There were no safety issues with the fueling or operation of the fuel cells. Although maintenance costs for the fuel cells were higher than for batteries, these costs are expected to decrease significantly in the next generation of fuel cells, making them even more cost effective.

  12. Auxiliary services offered to operator of transmissive system - the primary and secondary regulation of active capacity in ENO, o.z

    International Nuclear Information System (INIS)

    The change of outmoded analogue regulators of turbogenerators of Novaky Thermal Power Plant (TG ENO) B1 and B2 to new digital assigned the basic condition for fulfilment of strict rules for providing of auxiliary services - of primary and secondary regulation of active capacity and regulation of turns. The paper deals with technical and program sources for realisation of marked auxiliary services on the level of direct regulation of bloc, with fulfilment and evaluating of auxiliary services according to valid norm PNE 34-01/2002 in condensation and power take off operation of blocks after realisation of extraction of heat in hot water from ENO B. The paper argues, that regulation attributes of block - regulation zone of active capacity for primary and secondary regulation as like as the parameters of these regulations have been not changed by power take off operation. (author)

  13. Modeling of High Efficiency Solar Cells Under Laser Pulse for Power Beaming Applications

    Science.gov (United States)

    Jain, Raj K.; Landis, Geoffrey A.

    1994-01-01

    Solar cells may be used as receivers for laser power beaming. To understand the behavior of solar cells when illuminated by a pulsed laser, the time response of gallium arsenide and silicon solar cells to pulsed monochromatic input has been modeled using a finite element solar cell model.

  14. Accuracy of marker-assisted selection with auxiliary traits

    Indian Academy of Sciences (India)

    P Narain

    2003-09-01

    Genetic information on molecular markers is increasingly being used in plant and animal improvement programmes particularly as indirect means to improve a metric trait by selection either on an individual basis or on the basis of an index incorporating such information. This paper examines the utility of an index of selection that not only combines phenotypic and molecular information on the trait under improvement but also combines similar information on one or more auxiliary traits. The accuracy of such a selection procedure has been theoretically studied for sufficiently large populations so that the effects of detected quantitative trait loci can be perfectly estimated. The theory is illustrated numerically by considering one auxiliary trait. It is shown that the use of an auxiliary trait improves the selection accuracy; and, hence, the relative efficiency of index selection compared to individual selection which is based on the same intensity of selection. This is particularly so for higher magnitudes of residual genetic correlation and environmental correlation having opposite signs, lower values of the proportion of genetic variation in the main trait associated with the markers, negligible proportion of genetic variation in the auxiliary trait associated with the markers, and lower values of the heritability of the main trait but higher values of the heritability of the auxiliary trait.

  15. Environmental impact assessment of the incineration of municipal solid waste with auxiliary coal in China.

    Science.gov (United States)

    Zhao, Yan; Xing, Wei; Lu, Wenjing; Zhang, Xu; Christensen, Thomas H

    2012-10-01

    The environmental impacts of waste incineration with auxiliary coal were investigated using the life-cycle-based software, EASEWASTE, based on the municipal solid waste (MSW) management system in Shuozhou City. In the current system, MSW is collected, transported, and incinerated with 250 kg of coal per ton of waste. Based on observed environmental impacts of incineration, fossil CO(2) and heavy metals were primary contributors to global warming and ecotoxicity in soil, respectively. Compared with incinerators using excess coal, incineration with adequate coal presents significant benefits in mitigating global warming, whereas incineration with a mass of coal can avoid more impacts to acidification, photochemical ozone and nutrient enrichment because of increased electricity substitution and reduced emission from coal power plants. The "Emission standard of air pollutants for thermal power plants (GB13223-2011)" implemented in 2012 introduced stricter policies on controlling SO(2) and NO(x) emissions from coal power plants. Thus, increased use of auxiliary coal during incineration yields fewer avoided impacts on acidification and nutrient enrichment. When two-thirds of ash is source-separated and landfilled, the incineration of rest-waste presents better results on global warming, acidification, nutrient enrichment, and even ecotoxicity in soil. This process is considered a promising solution for MSW management in Shuozhou City. Weighted normalized environmental impacts were assessed based on Chinese political reduction targets. Results indicate that heavy metal and acidic gas emissions should be given more attention in waste incineration. This study provides scientific support for the management of MSW systems dominated by incineration with auxiliary coal in China. PMID:22683228

  16. Effects of the β1 auxiliary subunit on modification of Rat Na(v)1.6 sodium channels expressed in HEK293 cells by the pyrethroid insecticides tefluthrin and deltamethrin.

    Science.gov (United States)

    He, Bingjun; Soderlund, David M

    2016-01-15

    We expressed rat Nav1.6 sodium channels with or without the rat β1 subunit in human embryonic kidney (HEK293) cells and evaluated the effects of the pyrethroid insecticides tefluthrin and deltamethrin on whole-cell sodium currents. In assays with the Nav1.6 α subunit alone, both pyrethroids prolonged channel inactivation and deactivation and shifted the voltage dependence of channel activation and steady-state inactivation toward hyperpolarization. Maximal shifts in activation were ~18 mV for tefluthrin and ~24 mV for deltamethrin. These compounds also caused hyperpolarizing shifts of ~10-14 mV in the voltage dependence of steady-state inactivation and increased in the fraction of sodium current that was resistant to inactivation. The effects of pyrethroids on the voltage-dependent gating greatly increased the size of sodium window currents compared to unmodified channels; modified channels exhibited increased probability of spontaneous opening at membrane potentials more negative than the normal threshold for channel activation and incomplete channel inactivation. Coexpression of Nav1.6 with the β1 subunit had no effect on the kinetic behavior of pyrethroid-modified channels but had divergent effects on the voltage-dependent gating of tefluthrin- or deltamethrin-modified channels, increasing the size of tefluthrin-induced window currents but decreasing the size of corresponding deltamethrin-induced currents. Unexpectedly, the β1 subunit did not confer sensitivity to use-dependent channel modification by either tefluthrin or deltamethrin. We conclude from these results that functional reconstitution of channels in vitro requires careful attention to the subunit composition of channel complexes to ensure that channels in vitro are faithful functional and pharmacological models of channels in neurons. PMID:26708501

  17. Modelling of Auxiliary Devices for a Hardware-in-the-Loop Application

    OpenAIRE

    Olsén, Johan

    2005-01-01

    The engine torque is an important control signal. This signal is disturbed by the devices mounted on the belt. To better be able to estimate the torque signal, this work aims to model the auxiliary devices'influence on the crankshaft torque. Physical models have been developed for the air conditioning compressor, the alternator and the power steering pump. If these models are to be used in control unit function development and testing, they have to be fast enough to run on a hardware-in-the-l...

  18. Feasibility of AN Ecrh System for Jet:. Plant Layout, Auxiliaries and Services

    Science.gov (United States)

    Lennholm, M.; Bouquey, F.; Braune, H.; Farthing, J.; Garavaglia, S.; Giruzzi, G.; Granucci, G.; Jennison, M.; Parkin, A.

    2011-02-01

    A study conducted over the last year to asses the desirability and feasibility of installing an ECRH system on the JET tokamak has concluded that such a system is indeed both desirable and feasible. Details of physics studies, launcher and transmission line design, and power supplies are presented elsewhere in these proceedings. This paper concentrates on the logistical implications of installing this system at JET. The paper addresses issues such as port allocation and plant location. The study has concluded that a new building will be needed to house the ECRH plant. Building layout proposals are presented together with considerations regarding the required auxiliary equipment.

  19. Implementation of Electromagnetically Induced Transparency in a Metamaterial Controlled with Auxiliary Waves

    Science.gov (United States)

    Nakanishi, Toshihiro; Kitano, Masao

    2015-08-01

    We propose a metamaterial to realize true electromagnetically induced transparency (EIT), where the incidence of an auxiliary electromagnetic wave called the control wave induces transparency for a probe wave. The analogy to the original EIT effect in an atomic medium is shown through analytical and numerical calculations derived from a circuit model for the metamaterial. We perform experiments to demonstrate the EIT effect of the metamaterial in the microwave region. The width and position of the transparent region can be controlled by the power and frequency of the control wave. We also observe asymmetric transmission spectra unique to the Fano resonance.

  20. Implementation of electromagnetically induced transparency in a metamaterial controlled with auxiliary waves

    CERN Document Server

    Nakanishi, Toshihiro

    2015-01-01

    We propose a metamaterial to realize true electromagnetically induced transparency (EIT), where the incidence of an auxiliary electromagnetic wave called the control wave induces transparency for a probe wave. The analogy to the original EIT effect in an atomic medium is shown through analytical and numerical calculations derived from a circuit model for the metamaterial. We performed experiments to demonstrate the EIT effect of the metamaterial in the microwave region. The width and position of the transparent region can be controlled by the power and frequency of the control wave. We also observed asymmetric transmission spectra unique to the Fano resonance.

  1. Maintenance centered on reliability applied to a NPP auxiliary feedwater system

    International Nuclear Information System (INIS)

    The main objective of maintenance in a NPP is to assure that structures, systems and components will perform their design functions with reliability and/or availability in order to allow a safe and economic electric power generation. Reliability-Centered Maintenance (RCM) is a method of systematic review to either develop or optimize Preventive Maintenance Programs. This paper presents the objectives, concepts, organization and methods used in the application of RCM to NPP. Some application examples are include in this paper, considering some components of the Auxiliary Feedwater System of a generic Westinghouse designed two-loop PWR NPP. (author). 4 refs., 3 figs

  2. Fort St. Vrain helium circulator auxiliary systems: dynamic performance evaluation and acceptance tests

    International Nuclear Information System (INIS)

    The purpose of the tests described is to show that the dynamic performance of the Fort St. Vrain helium circulator auxiliary systems satisfies all the guidelines and criteria established and agreed to by Public Service Company of Colorado (PSC), Proto-Power, and General Atomic Company (GA). Specifically, it is shown that transfers to and from backup bearing water and helium purification system transients do not cause any circulator trips. Furthermore, at PSC's request, in an effort to resolve any NFSC questions concerning these systems, the satisfactory repeatability of their dynamic performance is shown beyond any doubt.

  3. Hyperspectral Polymer Solar Cells, Integrated Power for Microsystems

    Energy Technology Data Exchange (ETDEWEB)

    Stiebitz, Paul [Rochester Institute of Technology, NY(United States)

    2014-05-27

    The purpose of this research is to address a critical technology barrier to the deployment of next generation autonomous microsystems – the availability of efficient and reliable power sources. The vast majority of research on microsystems has been directed toward the development and miniaturization of sensors and other devices that enhance their intelligence, physical, and networking capabilities. However, the research into power generating and power storage technologies has not keep pace with this development. This research leveraged the capabilities of RIT’s NanoPower Research Laboratories (NPRL) in materials for advanced lithium ion batteries, nanostructured photovoltaics, and hybrid betavoltaics to develop reliable power sources for microsystems.

  4. Design Characteristics of the Passive Auxiliary Feedwater System in APR+

    International Nuclear Information System (INIS)

    The passive auxiliary feedwater system (PAFS) is a typical passive safety system implemented for the APR+. The auxiliary feedwater system (AFWS) in the APR1400, which is the reference plant of the APR+, consists of two motor driven pumps, two turbine driven pumps, two water storage tanks, and related pipes and valves. The AFWS feeds emergency water to steam generators to cool down the reactor coolant system when the main feedwater is lost. To enhance the safety, the PAFS replaces the AFWS with a passive condensation heat exchanger (PCHX), a passive condensation cooling tank (PCCT), and a few valves and pipes in the APR+ design. In this paper, we propose the design requirements and conceptual design of the PAFS in order to evaluate the operability of the PAFS, to develop the APR+'s general arrangements for the auxiliary building, and to identify the important parameters to be quantified by experiments

  5. Auxiliary bearing design considerations for gas cooled reactors

    International Nuclear Information System (INIS)

    The need to avoid contamination of the primary system, along with other perceived advantages, has led to the selection of electromagnetic bearings (EMBs) in most ongoing commercial-scale gas cooled reactor (GCR) designs. However, one implication of magnetic bearings is the requirement to provide backup support to mitigate the effects of failures or overload conditions. The demands on these auxiliary or 'catcher' bearings have been substantially escalated by the recent development of direct Brayton cycle GCR concepts. Conversely, there has been only limited directed research in the area of auxiliary bearings, particularly for vertically oriented turbomachines. This paper explores the current state-of-the-art for auxiliary bearings and the implications for current GCR designs. (author)

  6. Enhanced Power Stability for Proton Conducting Solid Oxides Fuel Cells

    Energy Technology Data Exchange (ETDEWEB)

    Boris Merinov; William A. Goddard III; Sossina Haile; Adri van Duin; Peter Babilo; Sang Soo Han

    2005-12-29

    , which both theory and experiment agree is the cause of the low conductivity of multi-granular systems. Our plan for a future project is to use the theory to optimize the additives and processing conditions and following this with experiment on the most promising systems. The experimental part of this project focused on improving the synthetic techniques for controlling the grain size and making measurements on the properties of these systems as a function of doping of impurities and of process conditions. A significant attention was paid to screening potential cathode materials (transition metal perovskites) and anode electrocatalysts (metals) for reactivity with Y-doped BaZrO{sub 3}, fabrication compatibility, and chemical stability in fuel cell environment. A robust method for fabricating crack-free thin membranes, as well as methods for sealing anode and cathode chambers, have been successfully developed. Our Pt|BYZ|Pt fuel cell, with a 100 {micro}m thick Y-doped BaZrO{sub 3} electrolyte layer, demonstrates the peak power density and short circuit current density of 28 mW/cm{sup 2} and 130mA/cm{sup 2}, respectively. These are the highest values of this type of fuel cell. All of these provide the basis for a future project in which theory and computation are combined to develop modified ceramic electrolytes capable of both high proton conductivity and excellent mechanical and chemical stability.

  7. Challenges for fuel cells as stationary power resource in the evolving energy enterprise

    Science.gov (United States)

    Rastler, Dan

    The primary market challenges for fuel cells as stationary power resources in evolving energy markets are reviewed. Fuel cell power systems have significant barriers to overcome in their anticipated role as decentralized energy power systems. Market segments for fuel cells include combined heat and power; low-cost energy, premium power; peak shaving; and load management and grid support. Understanding the role and fit of fuel cell systems in evolving energy markets and the highest value applications are a major challenge for developers and government funding organizations. The most likely adopters of fuel cell systems and the challenges facing each adopter in the target market segment are reviewed. Adopters include generation companies, utility distribution companies, retail energy service providers and end-users. Key challenges include: overcoming technology risk; achieving retail competitiveness; understanding high value markets and end-user needs; distribution and service channels; regulatory policy issues; and the integration of these decentralized resources within the electrical distribution system.

  8. Direct power generation from waste coffee grounds in a biomass fuel cell

    Science.gov (United States)

    Jang, Hansaem; Ocon, Joey D.; Lee, Seunghwa; Lee, Jae Kwang; Lee, Jaeyoung

    2015-11-01

    We demonstrate the possibility of direct power generation from waste coffee grounds (WCG) via high-temperature carbon fuel cell technology. At 900 °C, the WCG-powered fuel cell exhibits a maximum power density that is twice than carbon black. Our results suggest that the heteroatoms and hydrogen contained in WCG are crucial in providing good cell performance due to its in-situ gasification, without any need for pre-reforming. As a first report on the use of coffee as a carbon-neutral fuel, this study shows the potential of waste biomass (e.g. WCG) in sustainable electricity generation in fuel cells.

  9. Improving Semi-Supervised Learning with Auxiliary Deep Generative Models

    DEFF Research Database (Denmark)

    Maaløe, Lars; Sønderby, Casper Kaae; Sønderby, Søren Kaae;

    Deep generative models based upon continuous variational distributions parameterized by deep networks give state-of-the-art performance. In this paper we propose a framework for extending the latent representation with extra auxiliary variables in order to make the variational distribution more...... expressive for semi-supervised learning. By utilizing the stochasticity of the auxiliary variable we demonstrate how to train discriminative classifiers resulting in state-of-the-art performance within semi-supervised learning exemplified by an 0.96% error on MNIST using 100 labeled data points. Furthermore...

  10. Auxiliary tensor fields for Sp(2,R) self-duality

    CERN Document Server

    Ivanov, Evgeny A; Zupnik, Boris M

    2014-01-01

    The coset Sp(2,R)/U(1) is parametrized by two real scalar fields. We generalize the formalism of auxiliary tensor (bispinor) fields in U(1) self-dual nonlinear models of abelian gauge fields to the case of Sp(2,R) self-duality. In this new formulation, Sp(2,R) duality of the nonlinear scalar-gauge equations of motion is equivalent to an Sp(2,R) invariance of the auxiliary interaction. We derive this result in two different ways, aiming at its further application to supersymmetric theories. We also consider an extension to interactions with higher derivatives.

  11. Bispinor Auxiliary Fields in Duality-Invariant Electrodynamics Revisited

    OpenAIRE

    Ivanov, E. A.; Zupnik, B. M.

    2012-01-01

    Motivated by a recent progress in studying the duality-symmetric models of nonlinear electrodynamics, we revert to the auxiliary tensorial (bispinor) field formulation of the O(2) duality proposed by us in arXiv:hep-th/0110074, arXiv:hep-th/0303192. In this approach, the entire information about the given duality-symmetric system is encoded in the O(2) invariant interaction Lagrangian which is a function of the auxiliary fields V_{\\alpha\\beta}, \\bar V_{\\dot \\alpha\\dot \\beta}. We extend this s...

  12. TMI-2 auxiliary building elevator shaft and pit decontamination

    International Nuclear Information System (INIS)

    Decontamination of the elevator pit and shaft in the auxiliary building at Three Mile Island Unit 2 (TMI-2) was performed to remove high radiation and contamination levels which prevented personnel from utilizing the elevator. The radiation and contamination levels in the TMI-2 auxiliary building elevator shaft have been reduced to the point where plant personnel are again permitted to ride in the elevator without a radiation work permit, with the exception of access to the 281-ft (basement) level. Based on the declassification and expanded use of the elevator, the task goal has been met. The tax expended 16.16 man-rem and 621 man-hours

  13. Vanishing auxiliary variables in PPS sampling - with applications in microscopy

    DEFF Research Database (Denmark)

    Andersen, Ina Trolle; Hahn, Ute; Jensen, Eva B. Vedel

    auxiliary variables are a common phenomenon in microscopy and, accordingly, part of the population is not accessible, using PPS sampling. We propose a modification of the design, for which an optimal solution can be found, using a model assisted approach. The optimal design has independent interest in......Recently, non-uniform sampling has been suggested in microscopy to increase efficiency. More precisely, sampling proportional to size (PPS) has been introduced where the probability of sampling a unit in the population is proportional to the value of an auxiliary variable. Unfortunately, vanishing...

  14. Power system with an integrated lubrication circuit

    Science.gov (United States)

    Hoff, Brian D.; Akasam, Sivaprasad; Algrain, Marcelo C.; Johnson, Kris W.; Lane, William H.

    2009-11-10

    A power system includes an engine having a first lubrication circuit and at least one auxiliary power unit having a second lubrication circuit. The first lubrication circuit is in fluid communication with the second lubrication circuit.

  15. High-power biofuel cell textiles from woven biscrolled carbon nanotube yarns

    Science.gov (United States)

    Kwon, Cheong Hoon; Lee, Sung-Ho; Choi, Young-Bong; Lee, Jae Ah; Kim, Shi Hyeong; Kim, Hyug-Han; Spinks, Geoffrey M.; Wallace, Gordon G.; Lima, Márcio D.; Kozlov, Mikhail E.; Baughman, Ray H.; Kim, Seon Jeong

    2014-06-01

    Biofuel cells that generate electricity from glucose in blood are promising for powering implantable biomedical devices. Immobilizing interconnected enzyme and redox mediator in a highly conducting, porous electrode maximizes their interaction with the electrolyte and minimizes diffusion distances for fuel and oxidant, thereby enhancing power density. Here we report that our separator-free carbon nanotube yarn biofuel cells provide an open-circuit voltage of 0.70 V, and a maximum areal power density of 2.18 mW cm-2 that is three times higher than for previous carbon nanotube yarn biofuel cells. Biofuel cell operation in human serum provides high areal power output, as well as markedly increased lifetime (83% remained after 24 h), compared with previous unprotected biofuel cells. Our biscrolled yarn biofuel cells are woven into textiles having the mechanical robustness needed for implantation for glucose energy harvesting.

  16. Performance evaluation of aluminum/phosphate cell for powering small electronic devices

    Directory of Open Access Journals (Sweden)

    Gymama Slaughter

    2015-12-01

    Full Text Available We report on an innovative membrane-free aluminum/phosphate cell based on the activation of aluminum (Al as anodic material using ZnO nanocrystal in phosphate rich electrolyte that is capable of generating sufficient power to power a light-emitting diode (LED, selected as a model of a small electronic device. The energy from the cell is periodically supplied in high power bursts due to the charge and discharge cycle of the capacitor. The entire process is controlled by a switched capacitor regulator. The Al/phosphate cell was studied in neutral 100 mM phosphate buffer solution (7.4 at a temperature of 25 °C. We demonstrate that two Al/phosphate cells connected in series can generate an open circuit voltage (Voc up to 1.66 V to continuously power a LED via a switched capacitor regulator circuit. The switched capacitor regulator circuit enabled the 1 μF capacitor to store the incoming power from the cell and discharge it in a large power burst to supply the necessary drive strength required by the LED. This new Al/phosphate cell configuration is a ‘green’ alternative to the use of glucose abiotic and biofuel cells for powering ultra-low power implantable electronic devices.

  17. Special considerations on operating a fuel cell power plant using natural gas with marginal heating value

    Energy Technology Data Exchange (ETDEWEB)

    Moses, L. Ng; Chien-Liang Lin [Industrial Technology Research Institute, Taiwan (China); Ya-Tang Cheng [Power Research Institute, Taiwan (China)

    1996-12-31

    In realizing new power generation technologies in Taiwan, a phosphoric acid fuel cell power plant (model PC2513, ONSI Corporation) has been installed in the premises of the Power Research Institute of the Taiwan Power Company in Taipei County of Taiwan. The pipeline gas supplying to the site of this power plant has a high percentage of carbon dioxide and thus a slightly lower heating value than that specified by the manufacturer. Because of the lowering of heating value of input gas, the highest Output power from the power plant is understandably less than the rated power of 200 kW designed. Further, the transient response of the power plant as interrupted from the Grid is also affected. Since this gas is also the pipeline gas supplying to the heavily populated Taipei Municipal area, it is conceivable that the success of the operations of fuel cells using this fuel is of vital importance to the promotion of the use of this power generation technology in Taiwan. Hence, experiments were set up to assess the feasibility of this fuel cell power plant using the existing pipeline gas in this part of Taiwan where fuel cells would most likely find useful.

  18. Power conversion and quality of the Santa Clara 2 MW direct carbonate fuel cell demonstration plant

    Energy Technology Data Exchange (ETDEWEB)

    Skok, A.J. [Fuel Cell Engineering Corp., Danbury, CT (United States); Abueg, R.Z. [Basic Measuring Instruments, Santa Clara, CA (United States); Schwartz, P. [Fluor Daniel, Inc., Irvine, CA (United States)] [and others

    1996-12-31

    The Santa Clara Demonstration Project (SCDP) is the first application of a commercial-scale carbonate fuel cell power plant on a US electric utility system. It is also the largest fuel cell power plant ever operated in the United States. The 2MW plant, located in Santa Clara, California, utilizes carbonate fuel cell technology developed by Energy Research Corporation (ERC) of Danbury, Connecticut. The ultimate goal of a fuel cell power plant is to deliver usable power into an electrical distribution system. The power conversion sub-system does this for the Santa Clara Demonstration Plant. A description of this sub-system and its capabilities follows. The sub-system has demonstrated the capability to deliver real power, reactive power and to absorb reactive power on a utility grid. The sub-system can be operated in the same manner as a conventional rotating generator except with enhanced capabilities for reactive power. Measurements demonstrated the power quality from the plant in various operating modes was high quality utility grade power.

  19. Fuel Cell Powered Vehicles Using Supercapacitors: Device Characteristics, Control Strategies, and Simulation Results

    OpenAIRE

    Zhao, Hengbing; Burke, Andy

    2010-01-01

    The fuel cell powered vehicle is one of the most attractive candidates for the future due to its high efficiency and capability to use hydrogen as the fuel. However, its relatively poor dynamic response, high cost, and limited life time have impeded its widespread adoption. With the emergence of large supercapacitors (also know as ultracapacitors, UCs) with high power density and the shift to hybridization in the vehicle technology, fuel cell/supercapacitor hybrid fuel cell vehicles are gaini...

  20. Power

    OpenAIRE

    Bowles, Samuel; Gintis, Herbert

    2007-01-01

    We consider the exercise of power in competitive markets for goods, labour and credit. We offer a definition of power and show that if contracts are incomplete it may be exercised either in Pareto-improving ways or to the disadvantage of those without power. Contrasting conceptions of power including bargaining power, market power, and consumer sovereignty are considered. Because the exercise of power may alter prices and other aspects of exchanges, abstracting from power may miss essential a...

  1. Powering microbial electrolysis cells by capacitor circuits charged using microbial fuel cell

    KAUST Repository

    Hatzell, Marta C.

    2013-05-01

    A microbial electrolysis cell (MEC) was powered by a capacitor based energy storage circuit using energy from a microbial fuel cell (MFC) to increase MEC hydrogen production rates compared to that possible by the MFC alone. To prevent voltage reversal, MFCs charged the capacitors in a parallel configuration, and then the capacitors were discharged in series to boost the voltage that was used to power the MECs. The optimal capacitance for charging was found to be ∼0.01 F for each MFC. The use of the capacitor charging system increased energy recoveries from 9 to 13%, and hydrogen production rates increased from 0.31 to 0.72 m3 m-3-day-1, compared to coupled systems without capacitors. The circuit efficiency (the ratio of the energy that was discharged to the MEC to the energy provided to the capacitor from the MFCs) was ∼90%. These results provide an improved method for linking MFCs to MECs for renewable hydrogen gas production. © 2012 Elsevier B.V. All rights reserved.

  2. Evaluation of Effect of N2 Gas on the Cooling Capability of Passive Auxiliary Feedwater System (PAFS) in APR+

    International Nuclear Information System (INIS)

    In Korea, Advanced Power Reactor Plus (APR+) has being developed by adding passive safety features to Advanced Power Reactor 1400MWe (APR1400). Passive Auxiliary Feedwater System (PAFS) is one of passive system adopted in the APR+ to replace the conventional active auxiliary feedwater system. Because PAFS removes decay heat from the reactor core, it is required to verify the performance of PAFS in postulated accidents cases. In addition, an effect of noncondensable gas on the heat removal capability of PAFS should be evaluated since the non-condensable gas may deteriorate a condensation heat transfer through the condensation heat exchanger in PAFS. In this study, the effect of N2 gas was evaluated using MARS

  3. Prediction of the Power Output of Solar Cells Using Neural Networks: Solar Cells Energy Sector in Palestine

    Directory of Open Access Journals (Sweden)

    Ibrahim Qasrawi

    2015-11-01

    Full Text Available The prediction of the output power of solar cells in a given place has always been an important factor in planning the installation of solar cell panels, and guiding electrical companies to control, manage and distribute the energy into their electricity networks properly. The production of the electricity sector in Palestine using solar cells is a promising sector; this paper proposes a model which is used to predict future output power values of solar cells, which provides individuals and companies with future information, so they can organize their activities. We aim to create a model that able to connect time, place, and the relations between randomly distributed solar energy units. The system analyzes collected data from units through solar cells distributed in different places in Palestine. Multilayer Feed-Forward with Backpropagation Neural Networks (MFFNNBP is used to predict the power output of the solar cells in different places in Palestine. The model depends on predicting the future produce of the power output of solar cell depending on the real power output of the previous values. The data used in this paper depends on data collection of one day, month, and year. Finally, this proposed model conduct a systematic process with the aim of determining the most suitable places for an installation solar cell panel in different places in Palestine.

  4. Solid Oxide Fuel Cell – Gas Turbine Hybrid Power Plant

    OpenAIRE

    Henke, Moritz; Willich, Caroline; Steilen, Mike; Kallo, Josef; Friedrich, K. Andreas

    2013-01-01

    A model of a hybrid power plant consisting of SOFC and a gas turbine is presented. Simulations are carried out for a different number of SOFC stacks while keeping the output power of the SOFC constant. Results show that the effect of stack number on system performance is only marginal within the investigated range. Operating conditions of the SOFC, however, are strongly influenced.

  5. Low power and reliable SRAM memory cell and array design

    CERN Document Server

    Ishibashi, Koichiro

    2011-01-01

    Success in the development of recent advanced semiconductor device technologies is due to the success of SRAM memory cells. This book addresses various issues for designing SRAM memory cells for advanced CMOS technology. To study LSI design, SRAM cell design is the best materials subject because issues about variability, leakage and reliability have to be taken into account for the design.

  6. Development of KALIMER auxiliary sodium and cover gas management system

    International Nuclear Information System (INIS)

    The objectives of this report are to develop and to describe the auxiliary liquid metal and cover gas management systems of KALIMER. the system includes following system: (1) Auxiliary liquid metal system (2) Inert gas receiving and processing system (3) Impurity monitoring and analysis system. Auxiliary liquid metal and cover gas management system of KALIMER was developed. Functions of each systems and design basis were describes. The auxiliary liquid metal system receives, transfers, and purifies all sodium used in the plant. The system furnishes the required sodium quantity at the pressure, temperature, flow rate, and purity specified by the interfacing system. The intermediated sodium processing subsystem (ISPS) provides continuous purification of IHTS sodium, as well as performs the initial fill operation for both the IHTS and reactor vessel. The primary sodium processing subsystem provides purification (cold trapping) for sodium used in the reactor vessel. The inert gas receiving and processing (IGRP) system provides liquefied and ambient gas storage, delivers inert gases of specified composition and purity at regulated flow rates and pressures to points of usage throughout the KALIMER, and accepts the contaminated gases through its vacuum facilities for storage and transfer to the gas radwaste system. Three gases are used in the KALIMER: helium, argon, and nitrogen. 11 tabs., 12 figs. (Author)

  7. PWR auxiliary systems, safety and emergency systems, accident analysis, operation

    International Nuclear Information System (INIS)

    The author presents a description of PWR auxiliary systems like volume control, boric acid control, coolant purification, -degassing, -storage and -treatment system and waste processing systems. Residual heat removal systems, emergency systems and containment designs are discussed. As an accident analysis the author gives a survey over malfunctions and disturbances in the field of reactor operations. (TK)

  8. Auxiliary-field quantum Monte Carlo methods in nuclei

    CERN Document Server

    Alhassid, Y

    2016-01-01

    Auxiliary-field quantum Monte Carlo methods enable the calculation of thermal and ground state properties of correlated quantum many-body systems in model spaces that are many orders of magnitude larger than those that can be treated by conventional diagonalization methods. We review recent developments and applications of these methods in nuclei using the framework of the configuration-interaction shell model.

  9. Continuous Market Engineering - Focusing Agent Behavior, Interfaces, and Auxiliary Services

    OpenAIRE

    Kranz, Tobias Theodor

    2015-01-01

    Electronic markets spread out amongst business entities as well as private individuals. Albeit numerous approaches on developing electronic markets exist, a unified approach targeting market development, redesign, and refinement has been lacking. This thesis studies the potential of continuously improving electronic markets. Thereby, the experiments? design focuses on Agent Behavior, Interfaces, and Auxiliary Services and thus unveils the potential of continuously improving electronic markets.

  10. Regulation of Glutamate Receptors by Their Auxiliary Subunits

    OpenAIRE

    Tomita, Susumu

    2010-01-01

    Glutamate receptors are major excitatory receptors in the brain. Recent findings have established auxiliary subunits of glutamate receptors as critical modulators of synaptic transmission, synaptic plasticity and neurological disorder. The elucidation of the molecular rules governing glutamate receptors and subunits will improve our understanding of synapses and of neural-circuit regulation in the brain.

  11. High specific power, direct methanol fuel cell stack

    Science.gov (United States)

    Ramsey, John C.; Wilson, Mahlon S.

    2007-05-08

    The present invention is a fuel cell stack including at least one direct methanol fuel cell. A cathode manifold is used to convey ambient air to each fuel cell, and an anode manifold is used to convey liquid methanol fuel to each fuel cell. Tie-bolt penetrations and tie-bolts are spaced evenly around the perimeter to hold the fuel cell stack together. Each fuel cell uses two graphite-based plates. One plate includes a cathode active area that is defined by serpentine channels connecting the inlet manifold with an integral flow restrictor to the outlet manifold. The other plate includes an anode active area defined by serpentine channels connecting the inlet and outlet of the anode manifold. Located between the two plates is the fuel cell active region.

  12. A new approach for AC loss reduction in HTS transformer using auxiliary windings, case study: 25 kA HTS current injection transformer

    International Nuclear Information System (INIS)

    AC loss is one of the important parameters in HTS (high temperature superconducting) AC devices. Among the HTS AC power devices, the transformer is an essential part in the electrical power system. The AC losses in an HTS tape depend on the magnetic field. One of the techniques usually adopted to mitigate the unwanted magnetic field is using a system of coils that produce a magnetic field opposite to the incident one, reducing the total magnetic field. In this paper adding two auxiliary windings to the HTS transformer to produce this opposite magnetic field is proposed. The proper use of these auxiliary windings could reduce the leakage flux and, therefore, the AC loss. A mathematical model is used to describe the behaviour of a transformer operating with auxiliary windings, based on the theory of electromagnetic coupled circuits. The influence of the auxiliary windings on the leakage field is studied by the finite element method (FEM) and the AC loss of an HTS transformer was calculated. Also, the simulation results show that employing auxiliary windings will improve the HTS transformer efficiency

  13. Analysis of Condensation Phenomena in PAFS (Passive Auxiliary Feedwater System) Horizontal Heat Exchanger of APR+

    International Nuclear Information System (INIS)

    APR+ (Advanced Power Reactor Plus) is the next generation nuclear power plant in Korea. It adopts PAFS (Passive Auxiliary Feedwater System) on the secondary system. It can replace the conventional active system for auxiliary feedwater injection to the steam generator, and it enable to supply the coolant by a passive system. It cools down the secondary system by heat transfer at a horizontal U-tube in PCCT (Passive Condensate Cooling Tank). High pressure steam flow from the steam generator is condensed in the horizontal heat exchanger. The water in PCCT is maintained at an atmospheric pressure, so that boiling heat transfer at the outside wall of heat exchanger and natural convection occur in PCCT pool. The heat exchanger and PCCT is higher than steam generator, so condensate can be drained and injected to feedwater system without any active system. This study aims at design of the horizontal heat exchanger in PAFS. It should remove the heat generated in the steam generator. To satisfy this requirement, a system code analysis is conducted. The amount of condensation heat transfer is investigated by MARS (Multi-dimensional Analysis for Reactor Safety) code analysis

  14. Analysis of Condensation Phenomena in PAFS (Passive Auxiliary Feedwater System) Horizontal Heat Exchanger of APR+

    Energy Technology Data Exchange (ETDEWEB)

    Bae, Byoung Uhn; Yun, Byong Jo; Bae, Sung Won; Choi, Ki Yong; Song, Chul Hwa [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Cheon, Jong [Korea Hydro and Nuclear Power Co., Daejeon (Korea, Republic of)

    2009-10-15

    APR+ (Advanced Power Reactor Plus) is the next generation nuclear power plant in Korea. It adopts PAFS (Passive Auxiliary Feedwater System) on the secondary system. It can replace the conventional active system for auxiliary feedwater injection to the steam generator, and it enable to supply the coolant by a passive system. It cools down the secondary system by heat transfer at a horizontal U-tube in PCCT (Passive Condensate Cooling Tank). High pressure steam flow from the steam generator is condensed in the horizontal heat exchanger. The water in PCCT is maintained at an atmospheric pressure, so that boiling heat transfer at the outside wall of heat exchanger and natural convection occur in PCCT pool. The heat exchanger and PCCT is higher than steam generator, so condensate can be drained and injected to feedwater system without any active system. This study aims at design of the horizontal heat exchanger in PAFS. It should remove the heat generated in the steam generator. To satisfy this requirement, a system code analysis is conducted. The amount of condensation heat transfer is investigated by MARS (Multi-dimensional Analysis for Reactor Safety) code analysis.

  15. ENFICA-FC: Design of transport aircraft powered by fuel cell & flight test of zero emission 2-seater aircraft powered by fuel cells fueled by hydrogen

    OpenAIRE

    Cestino, Enrico; Borello, Fabio; Romeo, Giulio

    2013-01-01

    Fuel cells could become the main power source for small general aviation aircraft or could replace APU and internal sub-systems on larger aircraft, to obtain all-electric or more-electric air vehicles. There are several potential advantages of using such a power source, that range from environmental and economic issues to performance and operability aspects. A preliminary design is reported. Also, the paper contains a description of testing activities related to experimental flights of an all...

  16. A Maximum Power Point Tracking Control Method of a Photovoltaic Power Generator with Consideration of Dynamic Characteristics of Solar Cells

    Science.gov (United States)

    Watanabe, Takashi; Yoshida, Toshiya; Ohniwa, Katsumi

    This paper discusses a new control strategy for photovoltaic power generation systems with consideration of dynamic characteristics of the photovoltaic cells. The controller estimates internal currents of an equivalent circuit for the cells. This estimated, or the virtual current and the actual voltage of the cells are fed to a conventional Maximum-Power-Point-Tracking (MPPT) controller. Consequently, this MPPT controller still tracks the optimum point even though it is so designed that the seeking speed of the operating point is extremely high. This system may suit for applications, which are installed in rapidly changeable insolation and temperature-conditions e.g. automobiles, trains, and airplanes. The proposed method is verified by experiment with a combination of this estimating function and the modified Boehringer's MPPT algorithm.

  17. Design of Low Write-Power Consumption SRAM Cell Based on CNTFET at 32nm Technology

    OpenAIRE

    Rajendra Prasad S; B K Madhavi; K.Lal Kishore

    2011-01-01

    The SRAM which functions as the cache for system-on-chip is vital in the electronic industry. Carbon Nanotube Field Effect Transistor (CNFET) is used for high performance, high stability and low-power circuit designs as an alternative material to silicon in recent years. Therefore Design of SRAM Cell based on CNTFET is important for Low-power cache memory. In cells, the bit-lines are the most power consuming components because of larger power dissipation in driving long bit-line with large c...

  18. Integration of A Solid Oxide Fuel Cell into A 10 MW Gas Turbine Power Plant

    Directory of Open Access Journals (Sweden)

    Denver F. Cheddie

    2010-04-01

    Full Text Available Power generation using gas turbine power plants operating on the Brayton cycle suffers from low efficiencies. In this work, a solid oxide fuel cell (SOFC is proposed for integration into a 10 MW gas turbine power plant, operating at 30% efficiency. The SOFC system utilizes four heat exchangers for heat recovery from both the turbine outlet and the fuel cell outlet to ensure a sufficiently high SOFC temperature. The power output of the hybrid plant is 37 MW at 66.2% efficiency. A thermo-economic model predicts a payback period of less than four years, based on future projected SOFC cost estimates.

  19. Self-regulating control of parasitic loads in a fuel cell power system

    Science.gov (United States)

    Vasquez, Arturo (Inventor)

    2011-01-01

    A fuel cell power system comprises an internal or self-regulating control of a system or device requiring a parasitic load. The internal or self-regulating control utilizes certain components and an interconnection scheme to produce a desirable, variable voltage potential (i.e., power) to a system or device requiring parasitic load in response to varying operating conditions or requirements of an external load that is connected to a primary fuel cell stack of the system. Other embodiments comprise a method of designing such a self-regulated control scheme and a method of operating such a fuel cell power system.

  20. Binary co-generation power plant with night-temperature (SOFC) fuel cells of natural gas, v. 15(57)

    International Nuclear Information System (INIS)

    Binary co-generation power plant with height-temperature SOFC fuel cells of natural gas are presented in this paper. Based on before optimization calculations for this type of power plants is made: basic measures, number of modules, electric power and fuel cell efficiency; gas turbine electric power and efficiency; co-generation steam turbine electric and heat power efficiency. Compare analysis of binary co-generation power plant with SOFC fuel cells and co-generative power plant without fuel cells in relation of efficiency, ecological benefits and profitability (economy analysis) is given. (Author)

  1. Development of a thin film solar cell interconnect for the PowerSphere concept

    International Nuclear Information System (INIS)

    Progressive development of microsatellite technologies has resulted in increased demand for lightweight electrical power subsystems including solar arrays. The use of thin film photovoltaics has been recognized as a key solution to meet the power needs. The lightweight cells can generate sufficient power and still meet critical mass requirements. Commercially available solar cells produced on lightweight substrates are being studied as an option to fulfill the power needs. The commercially available solar cells are relatively inexpensive and have a high payoff potential. Commercially available thin film solar cells are primarily being produced for terrestrial applications. The need to convert the solar cell from a terrestrial to a space compatible application is the primary challenge. Solar cell contacts, grids and interconnects need to be designed to be atomic oxygen resistant and withstand rapid thermal cycling environments. A mechanically robust solar cell interconnect is also required in order to withstand handling during fabrication and survive during launch. The need to produce the solar cell interconnects has been identified as a primary goal of the PowerSphere program and is the topic of this paper. Details of the trade study leading to the final design involving the solar cell wrap around contact, flex blanket, welding process, and frame will be presented at the conference

  2. Impute DC link (IDCL) cell based power converters and control thereof

    Science.gov (United States)

    Divan, Deepakraj M.; Prasai, Anish; Hernendez, Jorge; Moghe, Rohit; Iyer, Amrit; Kandula, Rajendra Prasad

    2016-04-26

    Power flow controllers based on Imputed DC Link (IDCL) cells are provided. The IDCL cell is a self-contained power electronic building block (PEBB). The IDCL cell may be stacked in series and parallel to achieve power flow control at higher voltage and current levels. Each IDCL cell may comprise a gate drive, a voltage sharing module, and a thermal management component in order to facilitate easy integration of the cell into a variety of applications. By providing direct AC conversion, the IDCL cell based AC/AC converters reduce device count, eliminate the use of electrolytic capacitors that have life and reliability issues, and improve system efficiency compared with similarly rated back-to-back inverter system.

  3. Critical assessment of power trains with fuel-cell systems and different fuels

    Science.gov (United States)

    Höhlein, B.; von Andrian, S.; Grube, Th; Menzer, R.

    Legal regulations (USA, EU) are a major driving force for intensifying technological developments with respect to the global automobile market. In the future, highly efficient vehicles with very low emission levels will include low-temperature fuel-cell systems (PEFC) as units of electric power trains. With alcohols, ether or hydrocarbons used as fuels for these new electric power trains, hydrogen as PEFC fuel has to be produced on board. These concepts including the direct use of methanol in fuel-cell systems, differ considerably in terms of both their development prospects and the results achieved so far. Based on process engineering analyses for net electricity generation in PEFC-powered power trains, as well as on assumptions for electric power trains and vehicle configurations, different fuel-cell performances and fuel processing units for octane, diesel, methanol, ethanol, propane and dimethylether have been evaluated as fuels. The possible benefits and key challenges for different solutions of power trains with fuel-cell systems/on-board hydrogen production and with direct methanol fuel-cell (DMFC) systems have been assessed. Locally, fuel-cell power trains are almost emission-free and, unlike battery-powered vehicles, their range is comparable to conventional vehicles. Therefore, they have application advantages cases of particularly stringent emission standards requiring zero emission. In comparison to internal combustion engines, using fuel-cell power trains can lead to clear reductions in primary energy demand and global, climate-relevant emissions providing the advantage of the efficiency of the hydrogen/air reaction in the fuel cell is not too drastically reduced by additional conversion steps of on-board hydrogen production, or by losses due to fuel supply provision.

  4. Optimal design of PEM fuel cells to generate maximum power: A CFD study

    Directory of Open Access Journals (Sweden)

    Maher A.R. Sadiq Al-Baghdadi

    2011-11-01

    Full Text Available A full three-dimensional, multi-phase computational fluid dynamics model of a PEM fuel cell has been developed. The parametric study using this model has been performed and discussed in detail. Optimization study of a PEM fuel cell performance has been performed. The study quantifies and analyses the impact of operating, design, and material parameters on fuel cell performance and get an optimal design for PEM fuel cells to generate maximum power. To generate maximum power, the results show that the cell must be operate at higher cell operating temperature, higher cell operating pressure, higher stoichiometric flow ratio, and must have higher GDL porosity, higher GDL thermal conductivity, narrower gases channels, and thinner membrane. At these optimum conditions, the result shows that the total displacement and the degree of the deformation inside the MEA were decreased. However, the Miss stress in the membrane was increased due to higher cell operating temperature.

  5. Indigenous manufacturing realization of twin source and its auxiliary system

    International Nuclear Information System (INIS)

    operation) as well as Vacuum mode (DNB type vacuum immersed operation). The Twin Source shall be manufactured as per ASME guidelines for pressure vessel. Experiments on the Twin Source are foreseen in the near future, as all the auxiliary systems like 180 kW, RF generator system, vacuum vessel with Pumping station, Cooling water system, Data acquisition and control system (DACS) and other power supply systems are already installed in the lab premises. The paper discusses the FEA based engineering design, simplified manufacturing design, manufacturing experience with highlighting quality control and the system integration activities undertaken for the TWIN source test facility. (author)

  6. Light wire auxiliaries with pre-adjusted edgewise appliance to control individual incisor torque

    Directory of Open Access Journals (Sweden)

    Sharanya Sabrish

    2015-01-01

    The use of light wire auxiliaries have definite advantages and hence should be a part of our armamentarium to handle such cases. Light wire auxiliaries offer us a biomechanically superior and economical alternative to apply torque forces on incisors.

  7. An Analytical Method of Auxiliary Sources Solution for Plane Wave Scattering by Impedance Cylinders

    DEFF Research Database (Denmark)

    Larsen, Niels Vesterdal; Breinbjerg, Olav

    Analytical Method of Auxiliary Sources solutions for plane wave scattering by circular impedance cylinders are derived by transformation of the exact eigenfunction series solutions employing the Hankel function wave transformation. The analytical Method of Auxiliary Sources solution thus obtained...

  8. Multi-cell thermionic fuel element for nuclear electric power and propulsion system

    Science.gov (United States)

    Nikolaev, Yuri V.; Gontar, Alexander S.; Eremin, Stanislav A.; Lapochkin, Nikolai V.; Andreev, Pavel V.; Zhabotinsky, Evgeny E.

    1999-01-01

    Conceptual problems of development of two-mode multi-cell thermionic fuel element (TFE) for nuclear electric power and propulsion system are considered. The results of analysis of the design and TFE output parameters are presented. It is shown that application of advanced high effective materials and technologies provides operating of the TFE in two modes: a) in nominal mode of power generation for power supply of spacecraft payload at operational orbit and b) in forced mode of power generation for power supply of electric thrusters under spacecraft orbit transfer from intermediate to operational one.

  9. Small-Scale Low Cost Solid Oxide Fuel Cell Power Systems

    Energy Technology Data Exchange (ETDEWEB)

    S. D. Vora

    2008-02-01

    Progress in tasks seeking greater cell power density and lower cost through new cell designs, new cell materials and lower operating temperature is summarized. The design of the program required Proof-of-Concept unit of residential capacity scale is reviewed along with a summary of results from its successful test. Attachment 1 summarizes the status of cell development. Attachment 2 summarizes the status of generator design, and Attachment 3 of BOP design.

  10. Experimental Study on a Passive Fuel Cell/Battery Hybrid Power System

    Directory of Open Access Journals (Sweden)

    Yong-Song Chen

    2013-12-01

    Full Text Available A laboratory-scale passive hybrid power system for transportation applications is constructed and tested in this study. The hybrid power system consists of a fuel cell stack connected with a diode, a lithium-ion battery pack connected with a DC/DC power converter and another diode. The power converter is employed to regulate the output voltage of the battery pack. The dynamic responses of current and voltage of the stack to the start-up and acceleration of the load are experimentally investigated at two different selected output voltages of the DC/DC converter in the battery line. The power sharing of each power source and efficiency are also analyzed and discussed. Experimental results show that the battery can compensate for the shortage of supplied power for the load demand during the start-up and acceleration. The lowest operating voltage of the fuel cell stack is limited by the regulated output voltage of the DC/DC converter. The major power loss in the hybrid power system is attributed to the diodes. The power train efficiency can be improved by lowering the ratio of forward voltage drop of the diode to the operating voltage of the fuel cell stack.

  11. A Lemon Cell Battery for High-Power Applications

    Science.gov (United States)

    Muske, Kenneth R.; Nigh, Christopher W.; Weinstein, Randy D.

    2007-01-01

    The use of lemon cell battery to run an electric DC motor is demonstrated for chemistry students. This demonstration aids the students in understanding principles behind the design and construction of the lemon cell battery and principles governing the electric DC motor and other basic principles.

  12. A direct methanol fuel cell system to power a humanoid robot

    Science.gov (United States)

    Joh, Han-Ik; Ha, Tae Jung; Hwang, Sang Youp; Kim, Jong-Ho; Chae, Seung-Hoon; Cho, Jae Hyung; Prabhuram, Joghee; Kim, Soo-Kil; Lim, Tae-Hoon; Cho, Baek-Kyu; Oh, Jun-Ho; Moon, Sang Heup; Ha, Heung Yong

    In this study, a direct methanol fuel cell (DMFC) system, which is the first of its kind, has been developed to power a humanoid robot. The DMFC system consists of a stack, a balance of plant (BOP), a power management unit (PMU), and a back-up battery. The stack has 42 unit cells and is able to produce about 400 W at 19.3 V. The robot is 125 cm tall, weighs 56 kg, and consumes 210 W during normal operation. The robot is integrated with the DMFC system that powers the robot in a stable manner for more than 2 h. The power consumption by the robot during various motions is studied, and load sharing between the fuel cell and the back-up battery is also observed. The loss of methanol feed due to crossover and evaporation amounts to 32.0% and the efficiency of the DMFC system in terms of net electric power is 22.0%.

  13. Improvement of stability of sinusoidally driven atmospheric pressure plasma jet using auxiliary bias voltage

    OpenAIRE

    Hyun-Jin Kim; Jae Young Kim; Jae Hyun Kim; Dong Ha Kim; Duck-Sik Lee; Choon-Sang Park; Hyung Dal Park; Bhum Jae Shin; Heung-Sik Tae

    2015-01-01

    In this study, we have proposed the auxiliary bias pulse scheme to improve the stability of atmospheric pressure plasma jets driven by an AC sinusoidal waveform excitation source. The stability of discharges can be significantly improved by the compensation of irregular variation in memory voltage due to the effect of auxiliary bias pulse. From the parametric study, such as the width, voltage, and onset time of auxiliary bias pulse, it has been demonstrated that the auxiliary bias pulse plays...

  14. Hydrogen-chlorine fuel cell for production of hydrochloric acid and electric power : chlorine kinetics and cell design

    OpenAIRE

    Thomassen, Magnus Skinlo

    2005-01-01

    This thesis work is the continuation and final part of a joint project between the Department of Materials Technology, NTNU and Norsk Hydro Research Center in Porsgrunn, looking at the possibility of using fuel cells for production of hydrogen chloride and electric power. The experimental work encompass an evaluation of three hydrogen - chlorine fuel cell design concepts, development and implementation of a mathematical fuel cell model and a kinetic study of the chlorine reduction reaction. T...

  15. Accuracy of sentinel lymph node biopsy for the assessment of auxiliary status in patients with early (T1) breast carcinoma

    International Nuclear Information System (INIS)

    Objective: To determine the accuracy of SLN biopsy for the assessment of auxiliary status, and prognostic markers leading to lymphatic metastasis in patients with early (T1) breast cancer. Design: Cross-sectional study. Place and Duration of Study: Department of Surgery, Teaching and Research Hospital. Between January 2000 and August 2004. Patients and Methods: SLN mapping by blue dye method was performed on 39 patients with T1 breast carcinoma. SLNs, level 1 and 2 auxiliary nodes were dissected and excised. The size, pathologic features of the primary tumor, SLNs and other auxiliary nodes, and hormone receptors were evaluated by histopathologic examination. The rate of SLNs and non SLNs involvement, and demographic, clinical and pathologic risk factors leading to nodal metastasis were established. The diagnostic accuracy of SLN for auxiliary status was calculated. Results: SLNs were identified in 37 (95%) patients. The axilla had metastasis in 11 (28%) patients. Malignant cells involved SLNs in 8 patients. Non-SLNs had metastasis in 3 patients without SLN involvement. The sensitivity, specificity and accuracy of SLN biopsy for predicting auxiliary status was calculated as 73%, 100% and 92% respectively. Four of 5 patients T1c tumors (p=0.14) and lymphovascular invasion (p=0.0004). Conclusion: SLN biopsy with high diagnostic accuracy may prevent unnecessary disection of the axilla in the majority of patients with early (T1) breast carcinoma. Some risk factors as pre-menopausal status, absence of hormone receptors, and presence of lymphovascular invasion must be taken into account as important determinant of non-SLNs metastasis. (author)

  16. Maximum power efficiency operation and generalized predictive control of PEM (proton exchange membrane) fuel cell

    International Nuclear Information System (INIS)

    Operating a proton exchange membrane fuel cell (PEMFC) system to produce power at the maximum power efficiency is one of the key issues in PEMFC's wide-spread applications. However, power density exhibits complex behavior and nonlinear dynamics with respect to the output cell voltage, fuel cell temperature, anode and cathode pressure, inlet gas humidity, and so on. In this paper, the distribution of power density in the domain of the output cell voltage and fuel cell temperature is delineated. By this delineation, the quadratic polynomial fitting was used to approximate the power density curve in local interval and estimate the maximum power efficiency point. Generalized predictive control (GPC) is presented to overcome the problem of time-varying dynamics of PEMFC in real time via applying a forgetting factor recursive least square (FFRLS) method. Based on the approximation and generalized predictive control strategy, maximum power efficiency operation of PEMFC is applied. The results of this work can contribute to the operation of PEMFC at the maximum power point, which guarantees the plant generating maximum power at the lowest consumption of hydrogen. - Highlights: • Operating the PEMFC at the maximum power efficiency point is achieved with the lowest consumption of hydrogen. • The quadratic polynomial fitting method is used to estimate the maximum power efficiency point in local interval. • A data-driven predictive model is introduced to overcome the time-varying dynamics of PEMFC in real time. • Generalized predictive control (GPC) strategy is designed to optimize flow rates of hydrogen and coolant on-line

  17. Rapid Evaluation of Power Degradation in Series Connection of Single Feeding Microsized Microbial Fuel Cells

    KAUST Repository

    Rojas, Jhonathan Prieto

    2014-07-08

    We have developed a sustainable, single feeding, microsized, air-cathode and membrane-free microbial fuel cells with a volume of 40 mu L each, which we have used for rapid evaluation of power generation and viability of a series array of three cells seeking higher voltage levels. Contrary to expectations, the achieved power density was modest (45 mWm(-3)), limited due to non-uniformities in assembly and the single-channel feeding system.

  18. A Convergent Method of Auxiliary Sources for Two-Dimensional Impedance Scatterers With Edges

    DEFF Research Database (Denmark)

    Karamehmedovic, Mirza; Breinbjerg, Olav

    2001-01-01

    A modification to the Method of Auxiliary Sources (MAS) is introduced which renders the method operational for two-dimensional impedance scatterers with edges. The modification consists in letting the auxiliary surface converge to the scatterer physical surface for increasing number of auxiliary ...

  19. BE, DO, and Modal Auxiliaries of 3-Year-Old African American English Speakers

    Science.gov (United States)

    Newkirk-Turner, Brandi L.; Oetting, Janna B.; Stockman, Ida J.

    2014-01-01

    Purpose: This study examined African American English--speaking children's use of BE, DO, and modal auxiliaries. Method: The data were based on language samples obtained from 48 three-year-olds. Analyses examined rates of marking by auxiliary type, auxiliary surface form, succeeding element, and syntactic construction and by a number of child…

  20. Automotive Power Trains.

    Science.gov (United States)

    Marine Corps Inst., Washington, DC.

    This correspondence course, originally developed for the Marine Corps, is designed to provide mechanics with an understanding of the operation, maintenance, and troubleshooting of automotive power trains and certain auxiliary equipment. The course contains six study units covering basic power trains; clutch principles and operations; conventional…

  1. A polymer electrolyte fuel cell stack for stationary power generation from hydrogen fuel

    Energy Technology Data Exchange (ETDEWEB)

    Zawodzinski, C.; Wilson, M.; Gottesfeld, S. [Los Alamos National Lab., NM (United States)

    1996-10-01

    The fuel cell is the most efficient device for the conversion of hydrogen fuel to electric power. As such, the fuel cell represents a key element in efforts to demonstrate and implement hydrogen fuel utilization for electric power generation. A central objective of a LANL/Industry collaborative effort supported by the Hydrogen Program is to integrate PEM fuel cell and novel stack designs at LANL with stack technology of H-Power Corporation (H-Power) in order to develop a manufacturable, low-cost/high-performance hydrogen/air fuel cell stack for stationary generation of electric power. A LANL/H-Power CRADA includes Tasks ranging from exchange, testing and optimization of membrane-electrode assemblies of large areas, development and demonstration of manufacturable flow field, backing and bipolar plate components, and testing of stacks at the 3-5 cell level and, finally, at the 4-5 kW level. The stack should demonstrate the basic features of manufacturability, overall low cost and high energy conversion efficiency. Plans for future work are to continue the CRADA work along the time line defined in a two-year program, to continue the LANL activities of developing and testing stainless steel hardware for longer term stability including testing in a stack, and to further enhance air cathode performance to achieve higher energy conversion efficiencies as required for stationary power application.

  2. Battery Management System—Balancing Modularization Based on a Single Switched Capacitor and Bi-Directional DC/DC Converter with the Auxiliary Battery

    Directory of Open Access Journals (Sweden)

    Mohamed Daowd

    2014-04-01

    Full Text Available Lithium-based batteries are considered as the most advanced batteries technology, which can be designed for high energy or high power storage systems. However, the battery cells are never fully identical due to the fabrication process, surrounding environment factors and differences between the cells tend to grow if no measures are taken. In order to have a high performance battery system, the battery cells should be continuously balanced for maintain the variation between the cells as small as possible. Without an appropriate balancing system, the individual cell voltages will differ over time and battery system capacity will decrease quickly. These issues will limit the electric range of the electric vehicle (EV and some cells will undergo higher stress, whereby the cycle life of these cells will be shorter. Quite a lot of cell balancing/equalization topologies have been previously proposed. These balancing topologies can be categorized into passive and active balancing. Active topologies are categorized according to the active element used for storing the energy such as capacitor and/or inductive component as well as controlling switches or converters. This paper proposes an intelligent battery management system (BMS including a battery pack charging and discharging control with a battery pack thermal management system. The BMS user input/output interfacing. The battery balancing system is based on battery pack modularization architecture. The proposed modularized balancing system has different equalization systems that operate inside and outside the modules. Innovative single switched capacitor (SSC control strategy is proposed to balance between the battery cells in the module (inside module balancing, IMB. Novel utilization of isolated bidirectional DC/DC converter (IBC is proposed to balance between the modules with the aid of the EV auxiliary battery (AB. Finally an experimental step-up has been implemented for the validation of the

  3. Cochlear Outer-Hair-Cell Power Generation and Viscous Fluid Loss

    OpenAIRE

    Yanli Wang; Steele, Charles R.; Sunil Puria

    2016-01-01

    Since the discovery of otoacoustic emissions and outer hair cell (OHC) motility, the fundamental question of whether the cochlea produces mechanical power remains controversial. In the present work, direct calculations are performed on power loss due to fluid viscosity and power generated by the OHCs. A three-dimensional box model of the mouse cochlea is used with a feed-forward/feed-backward approximation representing the organ of Corti cytoarchitecture. The model is fit to in vivo basilar m...

  4. LRP2, an auxiliary receptor that controls sonic hedgehog signaling in development and disease.

    Science.gov (United States)

    Christ, Annabel; Herzog, Katja; Willnow, Thomas E

    2016-05-01

    To fulfill their multiple roles in organ development and adult tissue homeostasis, hedgehog (HH) morphogens act through their receptor Patched (PTCH) on target cells. However, HH actions also require HH binding proteins, auxiliary cell surface receptors that agonize or antagonize morphogen signaling in a context-dependent manner. Here, we discuss recent findings on the LDL receptor-related protein 2 (LRP2), an exemplary HH binding protein that modulates sonic hedgehog activities in stem and progenitor cell niches in embryonic and adult tissues. LRP2 functions are crucial for developmental processes in a number of tissues, including the brain, the eye, and the heart, and defects in this receptor pathway are the cause of devastating congenital diseases in humans. Developmental Dynamics 245:569-579, 2016. © 2016 Wiley Periodicals, Inc. PMID:26872844

  5. Power loss analysis of n-PASHA cells validated by 2D simulations

    Energy Technology Data Exchange (ETDEWEB)

    Janssen, G.J.M.; Gutjahr, A.; Burgers, A.R.; Saynova, D.S.; Cesar, I.; Romijn, I.G.

    2013-10-15

    To reach >21% efficiency for the n-Pasha (passivated all sides H-pattern) cell of ECN, reliable power-loss analyses are essential. A power-loss analysis is presented that is based on experimental data but validated and completed by 2D simulations. The analysis is used to identify the key factors that will contribute most to achieving >21% efficiency.

  6. Recovery Act. Solid Oxide Fuel Cell Diesel Auxilliary Power Unit Demonstration

    Energy Technology Data Exchange (ETDEWEB)

    Geiger, Gail E. [Delphi Automotive Systems, LLC., Gillingham (United Kingdom)

    2013-09-30

    Solid Oxide Fuel Cell Diesel Auxilliary Power Unit Demonstration Project. Summarizing development of Delphi’s next generation SOFC system as the core power plant to prove the viability of the market opportunity for a 3-5 kW diesel SOFC system. Report includes test and demonstration results from testing the diesel APU in a high visibility fleet customer vehicle application.

  7. AMPA receptors commandeer an ancient cargo exporter for use as an auxiliary subunit for signaling.

    Directory of Open Access Journals (Sweden)

    Nadine Harmel

    Full Text Available Fast excitatory neurotransmission in the mammalian central nervous system is mainly mediated by ionotropic glutamate receptors of the AMPA subtype (AMPARs. AMPARs are protein complexes of the pore-lining α-subunits GluA1-4 and auxiliary β-subunits modulating their trafficking and gating. By a proteomic approach, two homologues of the cargo exporter cornichon, CNIH-2 and CNIH-3, have recently been identified as constituents of native AMPARs in mammalian brain. In heterologous reconstitution experiments, CNIH-2 promotes surface expression of GluAs and modulates their biophysical properties. However, its relevance in native AMPAR physiology remains controversial. Here, we have studied the role of CNIH-2 in GluA processing both in heterologous cells and primary rat neurons. Our data demonstrate that CNIH-2 serves an evolutionarily conserved role as a cargo exporter from the endoplasmic reticulum (ER. CNIH-2 cycles continuously between ER and Golgi complex to pick up cargo protein in the ER and then to mediate its preferential export in a coat protein complex (COP II dependent manner. Interaction with GluA subunits breaks with this ancestral role of CNIH-2 confined to the early secretory pathway. While still taking advantage of being exported preferentially from the ER, GluAs recruit CNIH-2 to the cell surface. Thus, mammalian AMPARs commandeer CNIH-2 for use as a bona fide auxiliary subunit that is able to modify receptor signaling.

  8. Water rocket - Electrolysis propulsion and fuel cell power

    International Nuclear Information System (INIS)

    Water Rocket is the collective name for an integrated set of technologies that offer new options for spacecraft propulsion, power, energy storage, and structure. Low pressure water stored on the spacecraft is electrolyzed to generate, separate, and pressurize gaseous hydrogen and oxygen. These gases, stored in lightweight pressure tanks, can be burned to generate thrust or recombined to produce electric power. As a rocket propulsion system, Water Rocket provides the highest feasible chemical specific impulse (-400 seconds). Even higher specific impulse propulsion can be achieved by combining Water Rocket with other advanced propulsion technologies, such as arcjet or electric thrusters. With innovative pressure tank technology, Water Rocket's specific energy[Wh/kg] can exceed that of the best foreseeable batteries by an order of magnitude, and the tanks can often serve as vehicle structural elements. For pulsed power applications, Water Rocket propellants can be used to drive very high power density generators, such as MHD devices or detonation-driven pulse generators. A space vehicle using Water Rocket propulsion can be totally inert and non-hazardous during assembly and launch. These features are particularly important for the timely development and flight qualification of new classes of spacecraft, such as microsats, nanosats, and refuelable spacecraft

  9. Power loss for high-voltage solar-cell arrays

    Science.gov (United States)

    Parker, L. W.

    1979-01-01

    Electric field particle collection and power loss are calculated in program written in FORTRAN IV for use on UNIVAC 1100/40 computer. Program incorporates positive and negative and negative charge flows and balance between positive and negative flows is performed by iteration.

  10. Fuel cell programs in the United States for stationary power applications

    Energy Technology Data Exchange (ETDEWEB)

    Singer, M.

    1996-04-01

    The Department of Energy (DOE), Office of Fossil Energy, is participating with the private sector in sponsoring the development of molten carbonate fuel cell (MCFC) and solid oxide fuel cell (SOFC) technologies for application in the utility, commercial and industrial sectors. Phosphoric acid fuel cell (PAFC) development was sponsored by the Office of Fossil Energy in previous years and is now being commercialized by the private sector. Private sector participants with the Department of Energy include the Electric Power Research Institute (EPRI), the Gas Research institute (GRI), electric and gas utilities, universities, manufacturing companies and their suppliers. through continued government and private sector support, fuel cell systems are emerging power generation technologies which are expected to have significant worldwide impacts. An industry with annual sales of over a billion dollars is envisioned early in the 21st century. PAFC power plants have begun to enter the marketplace and MCFC and SOFC power plants are expected to be ready to enter the marketplace in the late 1990s. In support of the efficient and effective use of our natural resources, the fuel cell program seeks to increase energy efficiency and economic effectiveness of power generation. This is to be accomplished through effectiveness of power generation. This is accomplished through the development and commercialization of cost-effective, efficient and environmentally desirable fuel cell systems which will operate on fossil fuels in multiple and end use sectors.

  11. Feasibility Study on Passive Auxiliary Feedwater System in Loss of Condenser Vacuum Accident

    International Nuclear Information System (INIS)

    Nuclear leading countries are developing and constructing technology intensive pressurized water reactors (PWRs) such as AP1000 (United State), EPR (Europe), and US-APWR (Japan), and these advanced reactors adopt several passive safety features in order to enhance the safety and reliability. Domestic advanced reactor APR1400 already completed the earlier development in 2002, and technology gap from the nuclear leading countries become large. In particular, China requires technology transfer in the order of new power plant construction. Thus it is expected difficult to export the power plant to the newly developing countries without our own technology. Therefore, the improvement of competitive power and establishment of infra structure of advanced nuclear industry through innovative technology enhancement are urgent and essential to international competitive marketing. Passive safety features have been always adopted as an improved design concept in the development of innovative reactor design. Domestic nuclear industry has stated the development of APR+ as a Korean specific reactor for the export strategy. In the development of APR+ a passive auxiliary feedwater system (PAFS) has been considered as a noticeable candidate of improved design. Reference 2 reported that the adoption of PAFS, which can replace the auxiliary feedwater system, can prevent core damage in the accident of station black out (SBO), since Class 1E DC power operates the related valves, and 8 hours hot standby operation of plant without operation action is achievable. This PAFS contributes to the safety and economics, in that it decreases the core damage frequency 26% from 2.45E- 06/r-y to 1.80E-06/r-y, and it saves the construction cost 20 million Kr-Won. This paper discusses on the performance of PAFS for the accident of loss of condenser vacuum as a precursor of detailed design specification

  12. Feasibility Study on Passive Auxiliary Feedwater System in Loss of Condenser Vacuum Accident

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Soon Joon; Lee, Byung Chul [FNC Tech., Daejeon (Korea, Republic of); Cheon, Jong; Kim, Han Gon [NETEC, Daejeon (Korea, Republic of)

    2009-05-15

    Nuclear leading countries are developing and constructing technology intensive pressurized water reactors (PWRs) such as AP1000 (United State), EPR (Europe), and US-APWR (Japan), and these advanced reactors adopt several passive safety features in order to enhance the safety and reliability. Domestic advanced reactor APR1400 already completed the earlier development in 2002, and technology gap from the nuclear leading countries become large. In particular, China requires technology transfer in the order of new power plant construction. Thus it is expected difficult to export the power plant to the newly developing countries without our own technology. Therefore, the improvement of competitive power and establishment of infra structure of advanced nuclear industry through innovative technology enhancement are urgent and essential to international competitive marketing. Passive safety features have been always adopted as an improved design concept in the development of innovative reactor design. Domestic nuclear industry has stated the development of APR+ as a Korean specific reactor for the export strategy. In the development of APR+ a passive auxiliary feedwater system (PAFS) has been considered as a noticeable candidate of improved design. Reference 2 reported that the adoption of PAFS, which can replace the auxiliary feedwater system, can prevent core damage in the accident of station black out (SBO), since Class 1E DC power operates the related valves, and 8 hours hot standby operation of plant without operation action is achievable. This PAFS contributes to the safety and economics, in that it decreases the core damage frequency 26% from 2.45E- 06/r-y to 1.80E-06/r-y, and it saves the construction cost 20 million Kr-Won. This paper discusses on the performance of PAFS for the accident of loss of condenser vacuum as a precursor of detailed design specification.

  13. Study of a multiphase interleaved step-up converter for fuel cell high power applications

    International Nuclear Information System (INIS)

    This paper presents a study of a high power dc distributed system supplied by a fuel cell generator. A proposed parallel power converter with interleaving algorithm is chosen to boost a low dc voltage of fuel cell to a dc bus utility level. The present interleaved step-up converters are composed of two and four identical boost converters connected in parallel. Converters are controlled by interleaved switching signals, which have the same switching frequency and the same phase shift. By virtue of paralleling the converters, the input current can be shared among the cells or phases, so that high reliability and efficiency in power electronic systems can be obtained. In addition, it is possible to improve the system characteristics such as maintenance, repair, fault tolerance, and low heat dissipation. During the past decade, power electronics research has focused on the development of interleaved parallel converters. For an interleaving technique with a real fuel cell source, this work is the first presentation; it is not just a fuel cell simulation. So, the design and experimental verification of 1.2-kW prototype converters at a switching frequency of 25 kHz connected with a NexaTM PEM fuel cell system (1.2-kW, 46-A) in a laboratory is presented. Experimental results corroborate the excellent system performances. The fuel cell ripple current can be virtually reduced to zero. As a result, the fuel cell mean current is nearly equal to the fuel cell rms current.

  14. Study of a multiphase interleaved step-up converter for fuel cell high power applications

    Energy Technology Data Exchange (ETDEWEB)

    Thounthong, Phatiphat [Department of Teacher Training in Electrical Engineering, King Mongkut' s University of Technology North Bangkok, 1518 Piboolsongkram Rd., Bangsue, Bangkok 10800 (Thailand); Davat, Bernard [Nancy Research Group in Electrical Engineering, CNRS (UMR 7037), Nancy Universite, INPL-ENSEM 2, Avenue de la Foret de Haye, Vandoeuvre-les-Nancy, Lorraine 54516 (France)

    2010-04-15

    This paper presents a study of a high power dc distributed system supplied by a fuel cell generator. A proposed parallel power converter with interleaving algorithm is chosen to boost a low dc voltage of fuel cell to a dc bus utility level. The present interleaved step-up converters are composed of two and four identical boost converters connected in parallel. Converters are controlled by interleaved switching signals, which have the same switching frequency and the same phase shift. By virtue of paralleling the converters, the input current can be shared among the cells or phases, so that high reliability and efficiency in power electronic systems can be obtained. In addition, it is possible to improve the system characteristics such as maintenance, repair, fault tolerance, and low heat dissipation. During the past decade, power electronics research has focused on the development of interleaved parallel converters. For an interleaving technique with a real fuel cell source, this work is the first presentation; it is not just a fuel cell simulation. So, the design and experimental verification of 1.2-kW prototype converters at a switching frequency of 25 kHz connected with a Nexa trademark PEM fuel cell system (1.2-kW, 46-A) in a laboratory is presented. Experimental results corroborate the excellent system performances. The fuel cell ripple current can be virtually reduced to zero. As a result, the fuel cell mean current is nearly equal to the fuel cell rms current. (author)

  15. Contracted auxiliary Gaussian basis integral and derivative evaluation.

    Science.gov (United States)

    Giese, Timothy J; York, Darrin M

    2008-02-14

    The rapid evaluation of two-center Coulomb and overlap integrals between contracted auxiliary solid harmonic Gaussian functions is examined. Integral expressions are derived from the application of Hobson's theorem and Dunlap's product and differentiation rules of the spherical tensor gradient operator. It is shown that inclusion of the primitive normalization constants greatly simplifies the calculation of contracted functions corresponding to a Gaussian multipole expansion of a diffuse charge density. Derivative expressions are presented and it is shown that chain rules are avoided by expressing the derivatives as a linear combination of auxiliary integrals involving no more than five terms. Calculation of integrals and derivatives requires the contraction of a single vector corresponding to the monopolar result and its scalar derivatives. Implementation of the method is discussed and comparison is made with a Cartesian Gaussian-based method. The current method is superior for the evaluation of both integrals and derivatives using either primitive or contracted functions. PMID:18282025

  16. The auxiliary system design retrofits of the different coolant pump

    International Nuclear Information System (INIS)

    The coolant pump auxiliary systems retrofits are introduced in detail according to the different type of coolant pumps. The retrofit reasons of the chemical and volume control system, component cooling water system, Nuclear Nitrogen Storage and Distribution System, Vent and drain system, etc. are investigated. The most extraordinary change takes place in the chemical and volume control system and cooling water system. The charging flow temperature of re- generative heat exchanger and discharge flow of charging pump will be changed according to the difference coolant pump seal flow distribution. The commercial CFD software Flow master is employed to validate the charging capability. The other auxiliary systems' retrofits are also introduced in the end of this paper. (authors)

  17. Aging assessment of PWR [Pressurized Water Reactor] Auxiliary Feedwater Systems

    International Nuclear Information System (INIS)

    In support of the Nuclear Regulatory Commission's Nuclear Plant Aging Research (NPAR) Program, Oak Ridge National Laboratory is conducting a review of Pressurized Water Reactor Auxiliary Feedwater Systems. Two of the objectives of the NPAR Program are to identify failure modes and causes and identify methods to detect and track degradation. In Phase I of the Auxiliary Feedwater System study, a detailed review of system design and operating and surveillance practices at a reference plant is being conducted to determine failure modes and to provide an indication of the ability of current monitoring methods to detect system degradation. The extent to which current practices are contributing to aging and service wear related degradation is also being assessed. This paper provides a description of the study approach, examples of results, and some interim observations and conclusions. 1 fig., 1 tab

  18. An Analytical Method of Auxiliary Sources Solution for Plane Wave Scattering by Impedance Cylinders - A Reference Solution for the Numerical Method of Auxiliary Sources

    DEFF Research Database (Denmark)

    Larsen, Niels Vesterdal; Breinbjerg, Olav

    2004-01-01

    To facilitate the validation of the numerical Method of Auxiliary Sources an analytical Method of Auxiliary Sources solution is derived in this paper. The Analytical solution is valid for transverse magnetic, and electric, plane wave scattering by circular impedance Cylinders, and it is derived by...... singularities at different positions away from the origin. The transformation necessitates a truncation of the wave transformation but the inaccuracy introduced hereby is shown to be negligible. The analytical Method of Auxiliary Sources solution is employed as a reference to investigate the accuracy of the...... numerical Method of Auxiliary Sources for a range of scattering configurations....

  19. Experimental 1 kW 20 cell PEFC stack

    Energy Technology Data Exchange (ETDEWEB)

    Buechi, F.N.; Marmy, C.A.; Scherer, G.G. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Ruge, M. [Swiss Federal Inst. of Technology (ETH), Zuerich (Switzerland)

    1999-08-01

    A 20-cell PEFC stack was designed and built. Resin impregnated graphite was used as bipolar plate material. The air cooling of the stack was optimized by introducing high surface structures into the open space of the cooling plates. At {eta} (H{sub 2} LHV) = 0.5 a power of 880 W was obtained under conditions of low gas-pressures of 1.15 bar{sub a}. The auxiliary power for process air supply and cooling at 880 W power is less than 7% of the power output, indicating that the described system may be operated at a high efficiency. (author) 5 figs., 2 refs.

  20. Auxiliary representations of Lie algebras and the BRST constructions

    International Nuclear Information System (INIS)

    The method of construction of auxiliary representations for a given Lie algebra is discussed in the framework of the BRST approach. The corresponding BRST charge turns out to be nonhermitian. This problem is solved by the introduction of the additional kernel operator in the definition of the scalar product in the Fock space. The existence of the kernel operator is proved for any Lie algebra

  1. Auxiliary Field Meson Model at Finite Temperature and Density

    CERN Document Server

    Kouno, H; Kashiwa, K; Hamada, M; Tokudome, H; Matsuzaki, M; Yahiro, M

    2005-01-01

    Starting from many quark interactions, we construct a nonlinear sigma-omega model at finite temperature and density. The mesons are introduced as auxiliary fields. Effective quark-meson couplings are strongly related to effective meson masses, since they are derived simultaneously from the original many quark interactions. In this model, even if the effective omega-meson mass decreases due to the partial chiral restoration, the equation of state (EOS) of nuclear matter can become soft.

  2. Contracted auxiliary Gaussian basis integral and derivative evaluation

    OpenAIRE

    Giese, Timothy J.; York, Darrin M.

    2008-01-01

    The rapid evaluation of 2-center Coulomb and overlap integrals between contracted auxiliary solid harmonic Gaussian functions is examined. Integral expressions are derived from the application of Hobson’s theorem and Dunlap’s product and differentiation rules of the spherical tensor gradient operator. It is shown that inclusion of the primitive normalization constants greatly simplifies the calculation of contracted functions corresponding to a Gaussian multipole expansion of a diffuse charge...

  3. A simplified model for scheduling services on auxiliary bus lines

    OpenAIRE

    Codina Sancho, Esteve; Montero Mercadé, Lídia

    2014-01-01

    In this paper, a mathematical programming based model is described to assist with the schedule of services for a set of auxiliary bus lines that operate alleviating a disruption of the regular transportation system during a given time period. In contrast to other models, considered static, service schedules are set taking into account demand fluctuations that may happen in that time period. Passenger flows are represented with a multi-commodity structure and disseminate throug...

  4. Auxiliary full-disc telescope for the European Solar Telescope

    Czech Academy of Sciences Publication Activity Database

    Sobotka, Michal; Klvaňa, Miroslav; Melich, Zbyněk; Rail, Zdeněk; Bettonvil, F.; Gelly, B.

    Bellingham : SPIE, 2010 - (McLean, I.), 77351Z-1-77351Z-8 ISBN 9780819482259. - (Proceedings of SPIE. 7735). [Ground-based and Airborne Instrumentation for Astronomy III. San Diego (US), 27.06.2010-02.07.2010] Grant ostatní: EU(XE) 212482 Institutional research plan: CEZ:AV0Z10030501; CEZ:AV0Z20430508 Keywords : auxiliary full-disc telescope * principal functions Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics

  5. Mixed Bayesian Networks with Auxiliary Variables for Automatic Speech Recognition

    OpenAIRE

    Stephenson, Todd Andrew; Magimai.-Doss, Mathew; Bourlard, Hervé

    2001-01-01

    Standard hidden Markov models (HMMs), as used in automatic speech recognition (ASR), calculate their emission probabilities by an artificial neural network (ANN) or a Gaussian distribution conditioned on the hidden state variable, considering the emissions independent of any other variable in the model. Recent work showed the benefit of conditioning the emission distributions on a discrete auxiliary variable, which is observed in training and hidden in recognition. Related work has shown the ...

  6. Enhancing Sentence Relation Modeling with Auxiliary Character-level Embedding

    OpenAIRE

    Li, Peng; Huang, Heng

    2016-01-01

    Neural network based approaches for sentence relation modeling automatically generate hidden matching features from raw sentence pairs. However, the quality of matching feature representation may not be satisfied due to complex semantic relations such as entailment or contradiction. To address this challenge, we propose a new deep neural network architecture that jointly leverage pre-trained word embedding and auxiliary character embedding to learn sentence meanings. The two kinds of word seq...

  7. A new topology of fuel cell hybrid power source for efficient operation and high reliability

    Science.gov (United States)

    Bizon, Nicu

    2011-03-01

    This paper analyzes a new fuel cell Hybrid Power Source (HPS) topology having the feature to mitigate the current ripple of the fuel cell inverter system. In the operation of the inverter system that is grid connected or supplies AC motors in vehicle application, the current ripple normally appears at the DC port of the fuel cell HPS. Consequently, if mitigation measures are not applied, this ripple is back propagated to the fuel cell stack. Other features of the proposed fuel cell HPS are the Maximum Power Point (MPP) tracking, high reliability in operation under sharp power pulses and improved energy efficiency in high power applications. This topology uses an inverter system directly powered from the appropriate fuel cell stack and a controlled buck current source as low power source used for ripple mitigation. The low frequency ripple mitigation is based on active control. The anti-ripple current is injected in HPS output node and this has the LF power spectrum almost the same with the inverter ripple. Consequently, the fuel cell current ripple is mitigated by the designed active control. The ripple mitigation performances are evaluated by indicators that are defined to measure the mitigation ratio of the low frequency harmonics. In this paper it is shown that good performances are obtained by using the hysteretic current control, but better if a dedicated nonlinear controller is used. Two ways to design the nonlinear control law are proposed. First is based on simulation trials that help to draw the characteristic of ripple mitigation ratio vs. fuel cell current ripple. The second is based on Fuzzy Logic Controller (FLC). The ripple factor is up to 1% in both cases.

  8. Modelling of TEXTOR edge plasma in discharges with auxiliary heating and neon puffing

    International Nuclear Information System (INIS)

    The problem of hot plasma interaction with the material walls is one of the burning questions, the solution of which is essential for the creation of a viable thermonuclear reactor. One of the ways to reduce the temperature of the plasma in contact with the wall elements and the heat loads on them is an increase of impurity radiation from the discharge. However, the source of radiation should be localized in the peripheral region and impurities should not contribute significantly to the energy balance of the central plasma and hinder its heating up to thermonuclear temperatures. The light impurities - from boron to neon - satisfy these requirements since they are ionized up to the helium-like states in a relatively thin layer at the discharge edge. The TEXTOR experiments have shown, that in discharges with auxiliary heating more than 95 % of the power can be radiated by neon puffing without the onset of Marfe or detachment and with the source of radiation staying in the vicinity of the last closed magnetic surface (LCMS), touching the limiter. It is remarkable that this state is compatible with a good exhaust of injected helium by the pump limiter ALT-II. In the present paper we elaborate a model of the edge plasma particle and energy balances for the case of discharges with auxiliary heating and neon puffing and compare the results of calculations with experimental data from TEXTOR. (author) 4 refs., 4 figs

  9. Experimental program for validation of cooling and operational performance of the APR+ Passive auxiliary feedwater system

    International Nuclear Information System (INIS)

    PAFS (Passive Auxiliary Feedwater System) is one of the advanced passive safety systems adopted in the APR+ (Advanced Power Reactor plus), which is intended to completely replace the conventional active auxiliary feedwater system. PAFS cools down the steam generator's secondary side, and eventually removes the decay heat from the reactor core by introducing a natural driving force mechanism; i.e., condensing steam in nearly horizontal U-tubes submerged inside the passive condensation cooling tank (PCCT). With an aim of validating the cooling and operational performance of the PAFS, an experimental program is in progress at KAERI (Korea Atomic Energy Research Institute), which is composed of two kinds of tests; the separate effect test and the integral effect test. The separate effect test, PASCAL (PAFS Condensing Heat Removal Assessment Loop), is in progress to experimentally investigate the condensation heat transfer and natural convection phenomena in PAFS. The integral effect test is being performed to confirm the operational performance of the PAFS coupled with the other reactor coolant systems (RCS) using the thermal hydraulic integral effect test facility, ATLAS (Advanced Thermal hydraulic test Loop for Accident Simulation). This paper summarizes the up to date experimental results of the separate effect test and the integral effect test for PAFS from a cooling and operational performance point of view

  10. Feasibility study of helically coiled tube condensation heat exchanger for a passive auxiliary feedwater system

    International Nuclear Information System (INIS)

    The Passive Auxiliary Feedwater System (PAFS) with nearly-horizontal heat exchangers is one of passive safety features of APR+ (Advanced Power Reactor Plus) which provides the auxiliary feedwater by means of natural circulation with condensation. It is feasible to increase the heat transfer capacity of the PAFS by employing a helically coiled heat exchanger due to additional secondary flow effect by centrifugal force. In addition, a compact and flexible design can be achieved in a fixed volume by using the helically coiled heat exchanger, which is one of the most important merits of implementing this heat exchanger. In this paper, the helically coiled heat exchanger has been employed for the PAFS instead of nearly-horizontal heat exchanger. In order to evaluate the heat transfer performance of the helically coiled heat exchanger, an in-tube condensation heat transfer correlation by Wongwises has been introduced into the system analysis code, MARS-KS. A comparative numerical study was conducted for both heat exchangers. The result shows that helically coiled heat exchanger has 20% higher heat transfer efficiency than existing nearly-horizontal heat exchanger. (author)

  11. Gas Boiler Powered by the Fuel Cell System

    OpenAIRE

    Nicolae Badea; Madalin Costin

    2014-01-01

    The paper presents a new solution for supply of boilers with electrical energy in the order to achieve autonomy from electrical grid. The paper presents the experimental system implemented in the university lab, the components and implementation in Matlab-Simulink for simulation. As a result of numeric simulation performed, the experimental bench has been achieved. The problem of power quality, especially the THD factor, affects the sensitivity of equipment at perturbations. In...

  12. On direct hydrogen fuel cell vehicles : modelling and demonstration

    OpenAIRE

    Haraldsson, Kristina

    2005-01-01

    In this thesis, direct hydrogen Proton Exchange Membrane (PEM) fuel cell systems in vehicles are investigated through modelling, field tests and public acceptance surveys. A computer model of a 50 kW PEM fuel cell system was developed. The fuel cell system efficiency is approximately 50% between 10 and 45% of the rated power. The fuel cell auxiliary system, e.g. compressor and pumps, was shown to clearly affect the overall fuel cell system electrical efficiency. Two hydrogen on-board storage ...

  13. Bayesian Analysis of Geostatistical Models With an Auxiliary Lattice

    KAUST Repository

    Park, Jincheol

    2012-04-01

    The Gaussian geostatistical model has been widely used for modeling spatial data. However, this model suffers from a severe difficulty in computation: it requires users to invert a large covariance matrix. This is infeasible when the number of observations is large. In this article, we propose an auxiliary lattice-based approach for tackling this difficulty. By introducing an auxiliary lattice to the space of observations and defining a Gaussian Markov random field on the auxiliary lattice, our model completely avoids the requirement of matrix inversion. It is remarkable that the computational complexity of our method is only O(n), where n is the number of observations. Hence, our method can be applied to very large datasets with reasonable computational (CPU) times. The numerical results indicate that our model can approximate Gaussian random fields very well in terms of predictions, even for those with long correlation lengths. For real data examples, our model can generally outperform conventional Gaussian random field models in both prediction errors and CPU times. Supplemental materials for the article are available online. © 2012 American Statistical Association, Institute of Mathematical Statistics, and Interface Foundation of North America.

  14. Novel Sorbent to Clean Biogas for Fuel Cell Combined Heat and Power

    Energy Technology Data Exchange (ETDEWEB)

    None

    2009-11-01

    TDA Research Inc., in collaboration with FuelCell Energy, will develop a new, high-capacity sorbent to remove sulfur from anaerobic digester gas. This technology will enable the production of a nearly sulfur-free biogas to replace natural gas in fuel cell power plants while reducing greenhouse gas emissions from fossil fuels.

  15. Reliability analysis of the auxiliary feedwater system of Angra-1 including common cause failures using the multiple greek letter model

    International Nuclear Information System (INIS)

    The use of redundancy to increase the reliability of industrial systems make them subject to the occurrence of common cause events. The industrial experience and the results of safety analysis studies have indicated that common cause failures are the main contributors to the unreliability of plants that have redundant systems, specially in nuclear power plants. In this Thesis procedures are developed in order to include the impact of common cause failures in the calculation of the top event occurrence probability of the Auxiliary Feedwater System in a typical two-loop Nuclear Power Plant (PWR). For this purpose the Multiple Greek Letter Model is used. (author). 14 refs., 10 figs., 11 tabs

  16. Microcontroller based implementation of fuel cell and battery integrated hybrid power source

    International Nuclear Information System (INIS)

    This paper presents the implementation of a digitally controlled hybrid power source system, composed of fuel cell and battery. Use of individual fuel cell stacks as a power source, encounters many problems in achieving the desired load characteristics. A battery integrated, digitally controlled hybrid system is proposed for high pulse requirements. The proposed hybrid power source fulfils these peak demands with efficient flow of energy as compared to individual operations of fuel cell or battery system. A dc/dc converter is applied which provides an optimal control of power flow among fuel cell, battery and load. The proposed system efficiently overcomes the electrochemical constraints like over current, battery leakage current, and over and under voltage dips. By formulation of an intelligent algorithm and incorporating a digital technology (AVR Microcontroller), an efficient control is achieved over fuel cell current limit, battery charge, voltage and current. The hybrid power source is tested and analyzed by carrying out simulations using MATLAB simulink. Along with the attainment of desired complex load profiles, the proposed design can also be used for power enhancement and optimization for different capacities. (author)

  17. Dynamic behaviour of Li batteries in hydrogen fuel cell power trains

    Science.gov (United States)

    Veneri, O.; Migliardini, F.; Capasso, C.; Corbo, P.

    A Li ion polymer battery pack for road vehicles (48 V, 20 Ah) was tested by charging/discharging tests at different current values, in order to evaluate its performance in comparison with a conventional Pb acid battery pack. The comparative analysis was also performed integrating the two storage systems in a hydrogen fuel cell power train for moped applications. The propulsion system comprised a fuel cell generator based on a 2.5 kW polymeric electrolyte membrane (PEM) stack, fuelled with compressed hydrogen, an electric drive of 1.8 kW as nominal power, of the same typology of that installed on commercial electric scooters (brushless electric machine and controlled bidirectional inverter). The power train was characterized making use of a test bench able to simulate the vehicle behaviour and road characteristics on driving cycles with different acceleration/deceleration rates and lengths. The power flows between fuel cell system, electric energy storage system and electric drive during the different cycles were analyzed, evidencing the effect of high battery currents on the vehicle driving range. The use of Li batteries in the fuel cell power train, adopting a range extender configuration, determined a hydrogen consumption lower than the correspondent Pb battery/fuel cell hybrid vehicle, with a major flexibility in the power management.

  18. Major design issues of molten carbonate fuel cell power generation unit

    Energy Technology Data Exchange (ETDEWEB)

    Chen, T.P.

    1996-04-01

    In addition to the stack, a fuel cell power generation unit requires fuel desulfurization and reforming, fuel and oxidant preheating, process heat removal, waste heat recovery, steam generation, oxidant supply, power conditioning, water supply and treatment, purge gas supply, instrument air supply, and system control. These support facilities add considerable cost and system complexity. Bechtel, as a system integrator of M-C Power`s molten carbonate fuel cell development team, has spent substantial effort to simplify and minimize these supporting facilities to meet cost and reliability goals for commercialization. Similiar to other fuels cells, MCFC faces design challenge of how to comply with codes and standards, achieve high efficiency and part load performance, and meanwhile minimize utility requirements, weight, plot area, and cost. However, MCFC has several unique design issues due to its high operating temperature, use of molten electrolyte, and the requirement of CO2 recycle.

  19. Reliability considerations of a fuel cell backup power system for telecom applications

    Science.gov (United States)

    Serincan, Mustafa Fazil

    2016-03-01

    A commercial fuel cell backup power unit is tested in real life operating conditions at a base station of a Turkish telecom operator. The fuel cell system responds to 256 of 260 electric power outages successfully, providing the required power to the base station. Reliability of the fuel cell backup power unit is found to be 98.5% at the system level. On the other hand, a qualitative reliability analysis at the component level is carried out. Implications of the power management algorithm on reliability is discussed. Moreover, integration of the backup power unit to the base station ecosystem is reviewed in the context of reliability. Impact of inverter design on the stability of the output power is outlined. Significant current harmonics are encountered when a generic inverter is used. However, ripples are attenuated significantly when a custom design inverter is used. Further, fault conditions are considered for real world case studies such as running out of hydrogen, a malfunction in the system, or an unprecedented operating scheme. Some design guidelines are suggested for hybridization of the backup power unit for an uninterrupted operation.

  20. Characterization of a microfluidic microbial fuel cell as a power generator based on a nickel electrode.

    Science.gov (United States)

    Mardanpour, Mohammad Mahdi; Yaghmaei, Soheila

    2016-05-15

    This study reports the fabrication of a microfluidic microbial fuel cell (MFC) using nickel as a novel alternative for conventional electrodes and a non-phatogenic strain of Escherichia coli as the biocatalyst. The feasibility of a microfluidic MFC as an efficient power generator for production of bioelectricity from glucose and urea as organic substrates in human blood and urine for implantable medical devices (IMDs) was investigated. A maximum open circuit potential of 459 mV was achieved for the batch-fed microfluidic MFC. During continuous mode operation, a maximum power density of 104 Wm(-3) was obtained with nutrient broth. For the glucose-fed microfluidic MFC, the maximum power density of 5.2 μW cm(-2) obtained in this study is significantly greater than the power densities reported previously for microsized MFCs and glucose fuel cells. The maximum power density of 14 Wm(-3) obtained using urea indicates the successful performance of a microfluidic MFC using human excreta. It features high power density, self-regeneration, waste management and a low production cost (<$1), which suggest it as a promising alternative to conventional power supplies for IMDs. The performance of the microfluidic MFC as a power supply was characterized based on polarization behavior and cell potential in different substrates, operational modes, and concentrations. PMID:26720922

  1. Fuzzy Logic Based Controller for a Grid-Connected Solid Oxide Fuel Cell Power Plant

    OpenAIRE

    Chatterjee, Kalyan; Shankar, Ravi; Kumar, Amit

    2014-01-01

    This paper describes a mathematical model of a solid oxide fuel cell (SOFC) power plant integrated in a multimachine power system. The utilization factor of a fuel stack maintains steady state by tuning the fuel valve in the fuel processor at a rate proportional to a current drawn from the fuel stack. A suitable fuzzy logic control is used for the overall system, its objective being controlling the current drawn by the power conditioning unit and meet a desirable output power demand. The prop...

  2. A review and design of power electronics converters for fuel cell hybrid system applications

    DEFF Research Database (Denmark)

    Zhang, Zhe; Pittini, Riccardo; Andersen, Michael A. E.;

    2012-01-01

    This paper presents an overview of most promising power electronics topologies for a fuel cell hybrid power conversion system which can be utilized in many applications such as hybrid electrical vehicles (HEV), distributed generations (DG) and uninterruptible-power-supply (UPS) systems. Then, a...... multiple-input power conversion system including a decoupled dual-input converter and a three-phase neutral-point-clamped (NPC) inverter is proposed. The system can operate in both stand-alone and grid-connected modes. Simulation and experimental results are provided to show the feasibility of the proposed...

  3. Experimental Study on a Passive Fuel Cell/Battery Hybrid Power System

    OpenAIRE

    Yong-Song Chen; Sheng-Miao Lin; Boe-Shong Hong

    2013-01-01

    A laboratory-scale passive hybrid power system for transportation applications is constructed and tested in this study. The hybrid power system consists of a fuel cell stack connected with a diode, a lithium-ion battery pack connected with a DC/DC power converter and another diode. The power converter is employed to regulate the output voltage of the battery pack. The dynamic responses of current and voltage of the stack to the start-up and acceleration of the load are experimentally investig...

  4. Construction and characterization of spherical Si solar cells combined with SiC electric power inverter

    Science.gov (United States)

    Oku, Takeo; Matsumoto, Taisuke; Hiramatsu, Kouichi; Yasuda, Masashi; Shimono, Akio; Takeda, Yoshikazu; Murozono, Mikio

    2015-02-01

    Spherical silicon (Si) photovoltaic solar cell systems combined with an electric power inverter using silicon carbide (SiC) field-effect transistor (FET) were constructed and characterized, which were compared with an ordinary Si-based converter. The SiC-FET devices were introduced in the direct current-alternating current (DC-AC) converter, which was connected with the solar panels. The spherical Si solar cells were used as the power sources, and the spherical Si panels are lighter and more flexible compared with the ordinary flat Si solar panels. Conversion efficiencies of the spherical Si solar cells were improved by using the SiC-FET.

  5. Radiation resistance of thin-film solar cells for space photovoltaic power

    Science.gov (United States)

    Woodyard, James R.; Landis, Geoffrey A.

    1991-01-01

    Copper indium diselenide, cadmium telluride, and amorphous silicon alloy solar cells have achieved noteworthy performance and are currently being studied for space power applications. Cadmium sulfide cells had been the subject of much effort but are no longer considered for space applications. A review is presented of what is known about the radiation degradation of thin film solar cells in space. Experimental cadmium telluride and amorphous silicon alloy cells are reviewed. Damage mechanisms and radiation induced defect generation and passivation in the amorphous silicon alloy cell are discussed in detail due to the greater amount of experimental data available.

  6. Impact of power converter current ripple on the durability of a fuel cell stack

    OpenAIRE

    WAHDAME, B; GIRARDOT, L; Hissel, D.; Harel, F.; Francois, X.; Candusso, D.; PERA, MC; DUMERCY, L

    2008-01-01

    The durability and performance of Polymer Electrolyte Membrane Fuel Cell (PEMFC) have a major impact on the most important challenges facing fuel cell commercialization including final cost, mass production, system integration, functionality and reliability. This work is supported by French Government via an ANR' project (PAN'H) named SPACT80. The global objective is to develop and validate the use of a fuel cell based power system for heavy-duty vehicles (dedicated to railway applications or...

  7. Cell circuit design and test of a high power solid state modulator

    International Nuclear Information System (INIS)

    The cell circuit design and test of a high power solid state modulator for linac application are presented in the paper. The 3.3 kV IGBT and large dimension nanocrystalline core are used in the cell circuit design. The driving, protection, reverse energy absorbing and bias circuit are also presented. Dynamic magnetic performance of the core and the waveforms of the cell circuit are measured. (authors)

  8. Micro-tubular flame-assisted fuel cells for micro-combined heat and power systems

    Science.gov (United States)

    Milcarek, Ryan J.; Wang, Kang; Falkenstein-Smith, Ryan L.; Ahn, Jeongmin

    2016-02-01

    Currently the role of fuel cells in future power generation is being examined, tested and discussed. However, implementing systems is more difficult because of sealing challenges, slow start-up and complex thermal management and fuel processing. A novel furnace system with a flame-assisted fuel cell is proposed that combines the thermal management and fuel processing systems by utilizing fuel-rich combustion. In addition, the flame-assisted fuel cell furnace is a micro-combined heat and power system, which can produce electricity for homes or businesses, providing resilience during power disruption while still providing heat. A micro-tubular solid oxide fuel cell achieves a significant performance of 430 mW cm-2 operating in a model fuel-rich exhaust stream.

  9. Design and analysis of single- ended robust low power 8T SRAM cell

    Directory of Open Access Journals (Sweden)

    Gupta Neha

    2016-01-01

    Full Text Available This paper is based on the observation of 8T single ended static random access memory (SRAM and two techniques for reducing the sub threshold leakage current, power consumption are examined. In the first technique, effective supply voltage and ground node voltages are changed using a dynamic variable voltage level technique(VVL. In the second technique power supply is scaled down. This 8T SRAM cell uses one word line, two bitlinesand a transmission gate. Simulations and analytical results show that when the two techniques combine the new SRAM cell has correct read and write operation and also the cell contains 55.6% less leakage and the dynamic power is 98.8% less than the 8T single ended SRAM cell. Simulations are performed using cadence virtuoso tool at 45nm technology.

  10. Determination of intersecting curve between two surfaces of revolution with parallel axes by use of auxiliary planes and auxiliary spheres

    Directory of Open Access Journals (Sweden)

    Obradović Ratko

    2002-01-01

    Full Text Available In this paper the space intersecting curve between two surfaces of revolution with parallel axes of surfaces have been determined. Two mathematical models for determination of intersecting curve between two surfaces of revolution have been formed: auxiliary planes have been used in the first mathematical model and auxiliary spheres have been used in the second model (Obradović 2000. In the first case each auxiliary plane intersected with each surface of revolution on circle and two points of intersecting curve are obtained as intersecting points between these two circles. In the second case centres of two locks of auxiliary spheres are put on axes of surfaces of revolution (centre of first lock is on axis of the first surface of revolution and centre of second lock is on axis of the second surface of revolution on saine z coordinate (when axes of surfaces of revolution are parallel with z axis of coordinate system. First lock sphere intersects the first surface of revolution on w1 parallels and second lock corresponding sphere intersects the second surface of revolution on w2 circles. It is possible to find a relationship that for selected radius of the first lock sphere can determine the radius of second lock sphere and real points of intersecting curve have been determined by use of these two spheres. The points of intersecting curve between two surfaces of revolution are obtained by intersection between w1 circles from the first surface with w2 circles from the second surface (Obradović 2000.

  11. Fuel cell power systems for remote applications. Phase 1 final report and business plan

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-02-01

    The goal of the Fuel Cell Power Systems for Remote Applications project is to commercialize a 0.1--5 kW integrated fuel cell power system (FCPS). The project targets high value niche markets, including natural gas and oil pipelines, off-grid homes, yachts, telecommunication stations and recreational vehicles. Phase 1 includes the market research, technical and financial analysis of the fuel cell power system, technical and financial requirements to establish manufacturing capability, the business plan, and teaming arrangements. Phase 1 also includes project planning, scope of work, and budgets for Phases 2--4. The project is a cooperative effort of Teledyne Brown Engineering--Energy Systems, Schatz Energy Research Center, Hydrogen Burner Technology, and the City of Palm Desert. Phases 2 through 4 are designed to utilize the results of Phase 1, to further the commercial potential of the fuel cell power system. Phase 2 focuses on research and development of the reformer and fuel cell and is divided into three related, but potentially separate tasks. Budgets and timelines for Phase 2 can be found in section 4 of this report. Phase 2 includes: Task A--Develop a reformate tolerant fuel cell stack and 5 kW reformer; Task B--Assemble and deliver a fuel cell that operates on pure hydrogen to the University of Alaska or another site in Alaska; Task C--Provide support and training to the University of Alaska in the setting up and operating a fuel cell test lab. The Phase 1 research examined the market for power systems for off-grid homes, yachts, telecommunication stations and recreational vehicles. Also included in this report are summaries of the previously conducted market reports that examined power needs for remote locations along natural gas and oil pipelines. A list of highlights from the research can be found in the executive summary of the business plan.

  12. Power conditioning system topology for grid integration of wind and fuell cell energy

    Directory of Open Access Journals (Sweden)

    Marian GAICEANU

    2006-12-01

    Full Text Available This paper shows the topology of the hybrid grid-connected power system and the performances of the front-end three-phase power inverter. The renewable sources of the hybrid power system consist of a solid oxide fuel cell and a wind-turbine. This type of combination is the most efficient one. The proposed topology benefits of the one common DC-AC inverter which injects the generated power into the grid. The architecture diminishes the cost of the power conditioning system. Moreover, due to the power balance control of the entire power conditioning system the bulk dc link electrolytic capacitor is replaced with a small plastic film one. The final power conditioning system has the following advantages: independent control of the reactive power, minimize harmonic current distortion offering a nearly unity power factor operation (0,998 operation capability, dc link voltage regulation (up to 5% ripple in the dc-link voltage in any operated conditions, fast disturbance compensation capability, high reliability, and low cost. The experimental test has been performed and the performances of the grid power inverter are shown.

  13. Increasing the solar cell power output by coating with transition metal-oxide nanorods

    International Nuclear Information System (INIS)

    Highlights: → Nanoparticles enhance solar cell efficiency. → Solar cell power increase by nanorod coating. → Metal-oxide nanorods are prepared in flames. → Molybdenum oxide nanorods effectively scatter light on solar cell surface. → Scattering efficiency depends on coating density. -- Abstract: Photovoltaic cells produce electric current through interactions among photons from an ambient light source and electrons in the semiconductor layer of the cell. However, much of the light incident on the panel is reflected or absorbed without inducing the photovoltaic effect. Transition metal-oxide nanoparticles, an inexpensive product of a process called flame synthesis, can cause scattering of light. Scattering can redirect photon flux, increasing the fraction of light absorbed in the thin active layer of silicon solar cells. This research aims to demonstrate that the application of transition metal-oxide nanorods to the surface of silicon solar panels can enhance the power output of the panels. Several solar panels were coated with a nanoparticle-methanol suspension, and the power outputs of the panels before and after the treatment were compared. The results demonstrate an increase in power output of up to 5% after the treatment. The presence of metal-oxide nanorods on the surface of the coated solar cells is confirmed by electron microscopy.

  14. An overview of power electronics applications in fuel cell systems: DC and AC converters.

    Science.gov (United States)

    Ali, M S; Kamarudin, S K; Masdar, M S; Mohamed, A

    2014-01-01

    Power electronics and fuel cell technologies play an important role in the field of renewable energy. The demand for fuel cells will increase as fuel cells become the main power source for portable applications. In this application, a high-efficiency converter is an essential requirement and a key parameter of the overall system. This is because the size, cost, efficiency, and reliability of the overall system for portable applications primarily depend on the converter. Therefore, the selection of an appropriate converter topology is an important and fundamental aspect of designing a fuel cell system for portable applications as the converter alone plays a major role in determining the overall performance of the system. This paper presents a review of power electronics applications in fuel cell systems, which include various topology combinations of DC converters and AC inverters and which are primarily used in fuel cell systems for portable or stand-alone applications. This paper also reviews the switching techniques used in power conditioning for fuel cell systems. Finally, this paper addresses the current problem encountered with DC converters and AC inverter. PMID:25478581

  15. The construction of cloned Sika deer embryos (Cervus nippon hortulorum) by demecolcine auxiliary enucleation.

    Science.gov (United States)

    Yin, Y; Mei, M; Zhang, D; Zhang, S; Fan, A; Zhou, H; Li, Z

    2014-02-01

    The objective of our study was to establish the feasibility of experimental protocols for cloning sika deer. We performed auxiliary enucleation to improve the efficiency of nuclear transfer operation by optimizing the demecolcine concentration to induce cytoplasmic protrusions in the sika deer oocytes. In the present study,we had studied the impact of different demecolcine concentrations on cytoplasmic protrusions and enucleation rates. We determined that 95.9% of the sika deer oocytes formed cytoplasmic protrusions when treated for 1 h with 0.8 μg/ml demecolcine. The lowest observed rate of protrusion was 19.3% after overnight treatment with demecolcine. When the oocytes aged or had a poor cumulus expansion, they exhibited a significant decrease in the ability to form cytoplasmic protrusions. The rates of enucleation (94.9% vs 85.8%, p sika deer oocytes could be enucleated quickly and effectively using demecolcine auxiliary enucleation, which could enhance the enucleation rate, cell fusion rate and blastocyst rate of cloned embryos in vitro. PMID:24138424

  16. Roles of HIV-1 auxiliary proteins in viral pathogenesis and host-pathogen interactions

    Institute of Scientific and Technical Information of China (English)

    Lin LI; Hai Shan LI; C.David PAUZA; Michael BUKRINSKY; Richard Y ZHAO

    2005-01-01

    Active host-pathogen interactions take place during infection of human immunodeficiency virus type 1 (HIV-1).Outcomes of these interactions determine the efficiency of viral infection and subsequent disease progression. HIV-infected cells respond to viral invasion with various defensive strategies such as innate, cellular and humoral immune antiviral mechanisms. On the other hand, the virus has also developed various offensive tactics to suppress these host cellular responses. Among many of the viral offensive strategies, HIV- 1 viral auxiliary proteins (Tat, Rev, Nef, Vif, Vpr and Vpu) play important roles in the host-pathogen interaction and thus have significant impacts on the outcome of HIV infection. One of the best examples is the interaction of Vif with a host cytidine deaminase APOBEC3G. Although specific roles of other auxiliary proteins are not as well described as Vif-APOBEC3G interaction, it is the goal of this brief review to summarize some of the preliminary findings with the hope to stimulate further discussion and investigation in this exhilarating area of research.

  17. Low Power Laser Irradiation Stimulates the Proliferation of Adult Human Retinal Pigment Epithelial Cells in Culture

    Science.gov (United States)

    Song, Qing; Uygun, Basak; Banerjee, Ipsita; Nahmias, Yaakov; Zhang, Quan; Berthiaume, François; Latina, Mark; Yarmush, Martin L.

    2015-01-01

    We investigated the effects of low power laser irradiation on the proliferation of retinal pigment epithelial (RPE) cells. Adult human RPE cells were artificially pigmented by preincubation with sepia melanin, and exposed to a single sublethal laser pulse (590 nm, 1 µs, <200 mJ/cm2). DNA synthesis, cell number, and growth factor activity in irradiated RPE cells were subsequently monitored. The effect of sublethal laser irradiation on the “wound” healing response of an RPE monolayer in an in vitro scratch assay was also investigated. Single pulsed laser irradiation increased DNA synthesis in pigmented RPE cells measured 6 h post-treatment. In the scratch assay, laser irradiation increased the rates of cell proliferation and wound closure. Conditioned medium, collected 48 h following laser treatment, increased cell proliferation of unirradiated cells. Irradiation increased RPE cell secretion of platelet-derived growth factor (PDGF)-B chain, and increased mRNA levels of several growth factors and their receptors, including PDGF, transforming growth factor-β1, basic fibroblast growth factor, epidermal growth factor, insulin-like growth factor, as well as heat shock proteins. This demonstrates, for the first time, that low power single pulsed laser irradiation stimulates the proliferation of RPE cells, and upregulates growth factors that are mitogenic for RPE cells. PMID:26740823

  18. Power

    DEFF Research Database (Denmark)

    Elmholdt, Claus Westergård; Fogsgaard, Morten

    2016-01-01

    In this chapter, we will explore the dynamics of power in processes of creativity, and show its paradoxical nature as both a bridge and a barrier to creativity in organisations. Recent social psychological experimental research (Slighte, de Dreu & Nijstad, 2011) on the relation between power and...... creativity suggests that when managers give people the opportunity to gain power and explicate that there is reason to be more creative, people will show a boost in creative behaviour. Moreover, this process works best in unstable power hierarchies, which implies that power is treated as a negotiable and...... floating source for empowering people in the organisation. We will explore and discuss here the potentials, challenges and pitfalls of power in relation to creativity in the life of organisations today. The aim is to demonstrate that power struggles may be utilised as constructive sources of creativity. It...

  19. Use of fuel cells to meet military requirements for mobile power

    International Nuclear Information System (INIS)

    'Full text:' The use of fuel cell technology in military applications will depend on safe, high energy density systems being developed. An important part of using this technology is also the development of alternative hydrogen producing fuels with high energy densities and are easy to transport. Fuel cells are now a very large R and D effort for several military applications around the world. The major reason is because of the high power demands needed requires electrical energy sources that far exceed the capabilities of batteries currently being fielded for portable applications. Fuel cells are regarded as highly efficient, tactical energy converters that can be adapted for wide range of power requirements. They are potentially the lowest weight power source when coupled with batteries or capacitors to form hybrid systems. Generally electrical power is needed to support a number of applications from ultra-high power for electrical pulses (radios, sensors) to reliable, conditioned power for command and control systems. In the future, sustained power for electric drive systems, will also be required. Some of the promising applications in the military and the R and D challenges that remain to reach performance and reliability targets suitable for military requirements will be discussed. (author)

  20. Matching of Silicon Thin-Film Tandem Solar Cells for Maximum Power Output

    Directory of Open Access Journals (Sweden)

    C. Ulbrich

    2013-01-01

    Full Text Available We present a meaningful characterization method for tandem solar cells. The experimental method allows for optimizing the output power instead of the current. Furthermore, it enables the extraction of the approximate AM1.5g efficiency when working with noncalibrated spectra. Current matching of tandem solar cells under short-circuit condition maximizes the output current but is disadvantageous for the overall fill factor and as a consequence does not imply an optimization of the output power of the device. We apply the matching condition to the maximum power output; that is, a stack of solar cells is power matched if the power output of each subcell is maximal at equal subcell currents. The new measurement procedure uses additional light-emitting diodes as bias light in the JV characterization of tandem solar cells. Using a characterized reference tandem solar cell, such as a hydrogenated amorphous/microcrystalline silicon tandem, it is possible to extract the AM1.5g efficiency from tandems of the same technology also under noncalibrated spectra.

  1. Polymer Separators for High-Power, High-Efficiency Microbial Fuel Cells

    KAUST Repository

    Chen, Guang

    2012-12-26

    Microbial fuel cells (MFCs) with hydrophilic poly(vinyl alcohol) (PVA) separators showed higher Coulombic efficiencies (94%) and power densities (1220 mW m-2) than cells with porous glass fiber separators or reactors without a separator after 32 days of operation. These remarkable increases in both the coublomic efficiency and the power production of the microbial fuel cells were made possible by the separator\\'s unique characteristics of fouling mitigation of the air cathode without a large increase in ionic resistance in the cell. This new type of polymer gel-like separator design will be useful for improving MFC reactor performance by enabling compact cell designs. © 2012 American Chemical Society.

  2. Increasing the Cruise Range and Reducing the Capital Cost of Electric Vehicles by Integrating Auxiliary Unit with the Traction Drive

    Directory of Open Access Journals (Sweden)

    N. Satheesh Kumar

    2016-01-01

    Full Text Available Poor cruise performance of Electric Vehicles (EVs continues to be the primary reason that impends their market penetration. Adding more battery to extend the cruise range is not a viable solution as it increases the structural weight and capital cost of the EV. Simulations identified that a vehicle spends on average 15% of its total time in braking, signifying an immense potential of the utilization of regenerative braking mechanism. Based on the analysis, a 3 kW auxiliary electrical unit coupled with the traction drive during braking events increases the recoverable energy by 8.4%. In addition, the simulation revealed that, on average, the energy drawn from the battery is reduced by 3.2% when traction drive is integrated with the air-conditioning compressor (an auxiliary electrical load. A practical design solution of the integrated unit is also included in the paper. Based on the findings, it is evident that the integration of an auxiliary unit with the traction drive results in enhancing the energy capturing capacity of the regenerative braking mechanism and decreases the power consumed from the battery. Further, the integrated unit boosts other advantages such as reduced material cost, improved reliability, and a compact and lightweight design.

  3. Hydrogen Fuel Cell Analysis: Lessons Learned from Stationary Power Generation Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Scott E. Grasman; John W. Sheffield; Fatih Dogan; Sunggyu Lee; Umit O. Koylu; Angie Rolufs

    2010-04-30

    This study considered opportunities for hydrogen in stationary applications in order to make recommendations related to RD&D strategies that incorporate lessons learned and best practices from relevant national and international stationary power efforts, as well as cost and environmental modeling of pathways. The study analyzed the different strategies utilized in power generation systems and identified the different challenges and opportunities for producing and using hydrogen as an energy carrier. Specific objectives included both a synopsis/critical analysis of lessons learned from previous stationary power programs and recommendations for a strategy for hydrogen infrastructure deployment. This strategy incorporates all hydrogen pathways and a combination of distributed power generating stations, and provides an overview of stationary power markets, benefits of hydrogen-based stationary power systems, and competitive and technological challenges. The motivation for this project was to identify the lessons learned from prior stationary power programs, including the most significant obstacles, how these obstacles have been approached, outcomes of the programs, and how this information can be used by the Hydrogen, Fuel Cells & Infrastructure Technologies Program to meet program objectives primarily related to hydrogen pathway technologies (production, storage, and delivery) and implementation of fuel cell technologies for distributed stationary power. In addition, the lessons learned address environmental and safety concerns, including codes and standards, and education of key stakeholders.

  4. A Terrestrial Microbial Fuel Cell for Powering a Single-Hop Wireless Sensor Network

    Science.gov (United States)

    Zhang, Daxing; Zhu, Yingmin; Pedrycz, Witold; Guo, Yongxian

    2016-01-01

    Microbial fuel cells (MFCs) are envisioned as one of the most promising alternative renewable energy sources because they can generate electric current continuously while treating waste. Terrestrial Microbial Fuel Cells (TMFCs) can be inoculated and work on the use of soil, which further extends the application areas of MFCs. Energy supply, as a primary influential factor determining the lifetime of Wireless Sensor Network (WSN) nodes, remains an open challenge in sensor networks. In theory, sensor nodes powered by MFCs have an eternal life. However, low power density and high internal resistance of MFCs are two pronounced problems in their operation. A single-hop WSN powered by a TMFC experimental setup was designed and experimented with. Power generation performance of the proposed TMFC, the relationships between the performance of the power generation and the environment temperature, the water content of the soil by weight were measured by experiments. Results show that the TMFC can achieve good power generation performance under special environmental conditions. Furthermore, the experiments with sensor data acquisition and wireless transmission of the TMFC powering WSN were carried out. We demonstrate that the obtained experimental results validate the feasibility of TMFCs powering WSNs. PMID:27213346

  5. A Terrestrial Microbial Fuel Cell for Powering a Single-Hop Wireless Sensor Network.

    Science.gov (United States)

    Zhang, Daxing; Zhu, Yingmin; Pedrycz, Witold; Guo, Yongxian

    2016-01-01

    Microbial fuel cells (MFCs) are envisioned as one of the most promising alternative renewable energy sources because they can generate electric current continuously while treating waste. Terrestrial Microbial Fuel Cells (TMFCs) can be inoculated and work on the use of soil, which further extends the application areas of MFCs. Energy supply, as a primary influential factor determining the lifetime of Wireless Sensor Network (WSN) nodes, remains an open challenge in sensor networks. In theory, sensor nodes powered by MFCs have an eternal life. However, low power density and high internal resistance of MFCs are two pronounced problems in their operation. A single-hop WSN powered by a TMFC experimental setup was designed and experimented with. Power generation performance of the proposed TMFC, the relationships between the performance of the power generation and the environment temperature, the water content of the soil by weight were measured by experiments. Results show that the TMFC can achieve good power generation performance under special environmental conditions. Furthermore, the experiments with sensor data acquisition and wireless transmission of the TMFC powering WSN were carried out. We demonstrate that the obtained experimental results validate the feasibility of TMFCs powering WSNs. PMID:27213346

  6. Evaluation of the Total Cost of Ownership of Fuel Cell-Powered Material Handling Equipment

    Energy Technology Data Exchange (ETDEWEB)

    Ramsden, T.

    2013-04-01

    This report discusses an analysis of the total cost of ownership of fuel cell-powered and traditional battery-powered material handling equipment (MHE, or more typically 'forklifts'). A number of fuel cell MHE deployments have received funding support from the federal government. Using data from these government co-funded deployments, DOE's National Renewable Energy Laboratory (NREL) has been evaluating the performance of fuel cells in material handling applications. NREL has assessed the total cost of ownership of fuel cell MHE and compared it to the cost of ownership of traditional battery-powered MHE. As part of its cost of ownership assessment, NREL looked at a range of costs associated with MHE operation, including the capital costs of battery and fuel cell systems, the cost of supporting infrastructure, maintenance costs, warehouse space costs, and labor costs. Considering all these costs, NREL found that fuel cell MHE can have a lower overall cost of ownership than comparable battery-powered MHE.

  7. Stabilizing Canonical-Ensemble Calculations in the Auxiliary-Field Monte Carlo Method

    CERN Document Server

    Gilbreth, C N

    2014-01-01

    Quantum Monte Carlo methods are powerful techniques for studying strongly interacting Fermi systems. However, implementing these methods on computers with finite-precision arithmetic requires careful attention to numerical stability. In the auxiliary-field Monte Carlo (AFMC) method, low-temperature or large-model-space calculations require numerically stabilized matrix multiplication. When adapting methods used in the grand-canonical ensemble to the canonical ensemble of fixed particle number, the numerical stabilization increases the number of required floating-point operations for computing observables by a factor of the size of the single-particle model space, and thus can greatly limit the systems that can be studied. We describe an improved method for stabilizing canonical-ensemble calculations in AFMC that exhibits better scaling, and present numerical tests that demonstrate the accuracy and improved performance of the method.

  8. Designs for remote inspection of the ALMR Reactor Vessel Auxiliary Cooling System (RVACS)

    International Nuclear Information System (INIS)

    One of the most important safety systems in General Electric's (GI) Advanced Liquid Metal Reactor (ALMR) is the Reactor Vessel Auxiliary Cooling System (RVACS). Because of high temperature, radiation, and restricted space conditions, GI desired methods to remotely inspect the RVACS, emissive coatings, and reactor vessel welds during normal refueling operations. The DOE/NE Robotics for Advanced Reactors program formed a team to evaluate the ALMR design for remote inspection of the RVACS. Conceptual designs for robots to perform the required inspection tasks were developed by the team. Design criteria for these remote systems included robot deployment, power supply, navigation, environmental hardening of components, tether management, communication with an operator, sensing, and failure recovery. The operation of the remote inspection concepts were tested using 3-D simulation models of the ALMR. In addition, the team performed an extensive technology review of robot components that could survive the environmental conditions in the RVACS

  9. Internal resonance with commensurability induced by an auxiliary oscillator for broadband energy harvesting

    Science.gov (United States)

    Xiong, Liuyang; Tang, Lihua; Mace, Brian R.

    2016-05-01

    An internal resonance based broadband vibration energy harvester is proposed by introducing an auxiliary oscillator to the main nonlinear harvesting oscillator. Compared to conventional nonlinear energy harvesters, the natural frequencies of this two-degree-of-freedom nonlinear system can be easily adjusted to be commensurable which will result in more resonant peaks and better wideband performance. Experimental measurements and equivalent circuit simulations demonstrate that this design outperforms its linear counterpart. In addition to the open-circuit voltage, the optimal resistance to obtain the maximum power is determined. Nearly 130% increase in the bandwidth is achieved compared to the linear counterpart at an excitation level of 2 m/s2. The findings provide insight for the design of a broadband energy harvester when there is nonlinearity and internal resonance.

  10. Assessment of Heat Removal Capability of Passive Auxiliary Feedwater System using MARS Code

    International Nuclear Information System (INIS)

    Passive Auxiliary Feedwater System (PAFS) is one of advanced safety features under development for Advanced Power Reactor Plus (APR+). Because PAFS removes decay heats from the reactor core under transient and accident conditions, it is necessary to evaluate the heat removal capability of PAFS under the postulated accidents conditions. The target accidents cases analyzed in this study are the Loss of Condenser Vacuum (LOCV) and the Main Feedwater Line Break (MFLB). In the case of LOCV accident, PAFS in both loops are available but a single loop is operational in MFLB accident condition. Thus, these two accidents scenario are the proper selection to evaluate the capability of PAFS. For the analysis, MARS code is utilized and MARS model for PAFS is developed

  11. Investigation on Ledinegg Instability in Condensate Tube of Passive Auxiliary Feedwater System

    International Nuclear Information System (INIS)

    Passive Auxiliary Feedwater System (PAFS) is one of advanced safety features under development for Advanced Power Reactor Plus (APR+). Because the condensate flow is driven by natural circulation, it is important to ensure not to induce instabilities inside the condensate tube in PAFS for the effective cooling capability. Among the flow instabilities, the Ledineggtype instability may cause the severe deterioration of heat removal capability of PAFS since it can reduce the condensate flow even with slight change of pressure loss. Because the Ledinegg instability occurs when the pressure drop decreases with increasing flow, to evaluate the behavior of the pressure drop according to the change of mass flow rate is essential. For this reason, one-dimensional, integrated flow model is formulated and two-phase flow characteristics in the condensate tube are mathematically solved

  12. Comparison of auxiliary feedwater and EDRS operation during natural circulation of MRX

    International Nuclear Information System (INIS)

    The MRX is an integral type ship reactor with 100 MWt power, which is designed by Japan Atomic Energy Research Institute. It is characterized by integral type PWR, in-vessel type control rod drive mechanism, water-filled containment vessel and passive decay heat removal system. Marine reactor should have high passive safety. Therefore, in this study, we simulated the loss of flow accident to verify the passive decay heat removal by natural circulation using RETRAN-03 code. auxiliary feed water systems are used for decay heat removal mechanism and results are compared with the loss of flow accident analysis using emergency decay heat removal system by JAERI. Results are very similar to case of EDRS 1 loop operation in JAERI analysis and decay heat is successfully removed by natural circulation

  13. Experiment and numerical analysis of the NPP pressurizer auxiliary spray line submitted to large thermal shocks

    International Nuclear Information System (INIS)

    The pressurizer auxiliary spray line of PWR nuclear power plants may be submitted to severe temperature transients during upset conditions: a 325 deg C cold thermal shock in one second is followed by a 200 deg C hot thermal shock. For such transients, the RCC-M French design code rules that prevent the ratcheting deformation hazard are not respected for the components with thickness transition. Consequently, Electricite de France has realized twenty thermal cycles under pressure on a representative mock-up. During these tests, many temperature, strain and diametral variations were measured. No significant ratcheting deformation was detected on all components, except on the 6'' x 2'' x 6'' T-piece, where a weak progressive diameter increase was observed during a few cycles. Moreover, computations of a 2'' socket welding were made with the non linear kinematic hardening Chaboche model which also showed a weak progressive deformation behaviour. (authors). 7 figs., 7 refs

  14. Designs for remote inspection of the ALMR Reactor Vessel Auxiliary Cooling System (RVACS)

    Energy Technology Data Exchange (ETDEWEB)

    Sweeney, F.J. (Oak Ridge National Lab., TN (United States)); Carroll, D.G. (General Electric Co., San Jose, CA (United States)); Chen, C. (Tennessee Univ., Knoxville, TN (United States)); Crane, C.; Dalton, R. (Florida Univ., Gainesville, FL (United States)); Taylor, J.R. (Martin Marietta Energy Systems, Inc., Oak Ridge, TN (United States)); Tosunoglu, S. (Texas Univ., Austin, TX (United States))

    1993-01-01

    One of the most important safety systems in General Electric's (GI) Advanced Liquid Metal Reactor (ALMR) is the Reactor Vessel Auxiliary Cooling System (RVACS). Because of high temperature, radiation, and restricted space conditions, GI desired methods to remotely inspect the RVACS, emissive coatings, and reactor vessel welds during normal refueling operations. The DOE/NE Robotics for Advanced Reactors program formed a team to evaluate the ALMR design for remote inspection of the RVACS. Conceptual designs for robots to perform the required inspection tasks were developed by the team. Design criteria for these remote systems included robot deployment, power supply, navigation, environmental hardening of components, tether management, communication with an operator, sensing, and failure recovery. The operation of the remote inspection concepts were tested using 3-D simulation models of the ALMR. In addition, the team performed an extensive technology review of robot components that could survive the environmental conditions in the RVACS.

  15. GOTHIC Simulation of APR1400 Auxiliary Charging Pump room heat up

    Energy Technology Data Exchange (ETDEWEB)

    Ha, Hui-Un; Heo, Sun [KHNP, Daejeon (Korea, Republic of)

    2014-10-15

    As a part of the Advanced Power Reactor 1400 (APR1400) U. S. Nuclear Regulatory Commission Design Certification (NRC DC) project, we have been investigating Auxiliary Charging Pump (ACP) room heat up. With reference to the design specification of the ACP room, we determined input information and developed a GOTHIC model of the APR1400 ACP room. This calculation model is described herein, and representative results from the calculation are presented as well. The results of the present paper are used to determine the integrity of ACP operating in the accident. APR 1400 GOTHIC model was developed for ACP room heat up calculation. Calculation results confirm that door opening is cooling the room properly. It is found that the difference due to the surface option of heat conductors is insignificant. Based on this result, further studies should be performed to confirm integrity of ACP.

  16. Seismic response of base isolated auxiliary building with age related degradation

    International Nuclear Information System (INIS)

    The aging of an isolator affects not only the mechanical properties of the isolator but also the dynamic properties of the upper structure, such as the change in stiffness, deformation capacity, load bearing capacity, creep, and damping. Therefore, the seismic response of base isolated structures will change with time. The floor response in the base isolated nuclear power plants (NPPs) can be particularly changed because of the change in stiffness and damping for the isolator. The increased seismic response due to the aging of isolator can cause mechanical problems for many equipment located in the NPPs. Therefore, it is necessary to evaluate the seismic response of base isolated NPPs with age related degradation. In this study, the seismic responses for a base isolated auxiliary building of SHIN KORI 3 and 4 with age related degradation were investigated using a nonlinear time history analysis. Floor response spectrums (FRS) were presented with time for identifying the change in seismic demand under the aging of isolator

  17. Modelling of Temperature Profiles and Transport Scaling in Auxiliary Heated Tokamaks

    DEFF Research Database (Denmark)

    Callen, J.D.; Christiansen, J.P.; Cordey, J.G.;

    1987-01-01

    -mode) scaling with input power, . The constant heat pinch or excess temperature gradient model leads to the offset linear law for the total stored energy W with Pin, W = τinc Pin + W(0), which describes JET auxiliary heating data quite well. It also provides definitions for the incremental energy confinement......The temperature profiles produced by various heating profiles are calculated from local heat transport models. The models take the heat flux to be the sum of heat diffusion and a non-diffusive heat flow, consistent with local measurements of heat transport. Two models are developed analytically in...... detail: (i) a heat pinch or excess temperature gradient model with constant coefficients; and (ii) a non-linear heat diffusion coefficient (χ) model. Both models predict weak (lesssim20%) temperature profile responses to physically relevant changes in the heat deposition profile – primarily because the...

  18. The changing nature of the power generation market — does it create opportunities for fuel cells?

    Science.gov (United States)

    Cragg, C. T.

    This paper surveys the global power industry seeking trends that might encourage greater use of full cells. The subject is broken into four basic themes: (i) an increasing demand for electricity, and this may not be solved by the traditional form of the integrated state-owned, centralised power utility, with a large infrastructure grid attached, the load curves of these integrated grids becoming unmanageable; (ii) a general trend towards privatisation and deregulation in the power sector, that is shifting its control from an engineering to a commercial paradigm, with unforseen consequences; (iii) contrary to (ii), the need for supplying security in its most basic sense is increasing rather than declining as power-dependent technology becomes progressively more important in the modern economy, and (iv) the trend in technology, particularly environmental-friendly technology, is towards smaller size of production centres. Within these inter-related themes these are encouraging prospects for the fuel cell community.

  19. Fuel cell-shaft power packs (FC-SPP)

    Energy Technology Data Exchange (ETDEWEB)

    Elefsen, F.; Frandsen, S. [Danish Technological Institute, Renewable Energy and transport (Denmark)

    2007-05-15

    Danish companies will be able to obtain a unique international competitive position by combining our leadership in renewable energy with a focused and dedicated effort in hydrogen technology. The purpose of the present consortium is to establish the foundation for producing small hydrogen-based motor units. The consortium develops the technology in three concrete projects within two areas: small transportation equipment and mobile units. This assures that the research is directed towards specific market segments and that a synergy is obtained between technology development and market demand. Furthermore, the consortium involves developing concepts and tools for commercializing the technology and employing user-driven innovation. The consortium includes a number of innovative SMEs in close interaction with larger established companies. The large companies are primarily component suppliers, thus assuring that the necessary components are developed and produced. The participating SME's are both component and system suppliers, thus assuring that the products developed will also be carried to the market. Ultimately, the projects may contribute to the start of a new industrial success story similar to the Danish wind power industry, which would simultaneously lead to exports and an improved environment. (au)

  20. Photo-Activated Low Temperature, Micro Fuel Cell Power Source

    Energy Technology Data Exchange (ETDEWEB)

    Harry L. Tuller

    2007-03-30

    A Key objective of this program is to identify electrodes that will make it possible to significantly reduce the operating temperature of micro-SOFC and thin film-based SOFCs. Towards this end, efforts are directed towards: (a) identifying the key rate limiting steps which limit presently utilized electrodes from performing at reduced temperatures, as well as, (b) investigating the use of optical, as opposed to thermal energy, as a means for photocatalyzing electrode reactions and enabling reduced operating temperatures. During Phase I, the following objectives were achieved: (a) assembly and testing of our unique Microprobe Thin Film Characterization System; (b) fabrication of the model cathode materials system in thin film form by both PLD and ink jet printing; and (c) the successful configuration and testing of the model materials as cathodes in electrochemical cells. A further key objective (d) to test the potential of illumination in enhancing electrode performance was also achieved.

  1. Two-photon excitation in living cells induced by low-power cw laser beams

    Science.gov (United States)

    Koenig, Karsten; Krasieva, Tatiana B.; Liu, Yagang; Berns, Michael W.; Tromberg, Bruce J.

    1996-05-01

    We demonstrate multi-photon excitation in optically-trapped living cells. Intracellular non- resonant two-photon excitation of endogenous and exogenous chromophores was induced by CW near infrared (NIR) trapping beams of 105 mW power. In the case of fluorescent chromophores, detection of NIR-excited visible fluorescence was achieved by imaging and spectroscopy methods. Trap-induced, two-photon excited fluorescence was employed as a novel diagnostic method to monitor intracellular redox state and cell vitality of single motile spermatozoa and Chinese hamster ovary cells. We found, that nonlinear absorption of NIR photons NIR, single-frequency traps (`optical tweezers') for micromanipulation of vital cells.

  2. DPAL: A New Class of Lasers for CW Power Beaming at Ideal Photovoltaic Cell Wavelengths

    Energy Technology Data Exchange (ETDEWEB)

    Krupke, W F; Beach, R J; Payne, S A; Kanz, V K; Early, J T

    2003-09-15

    The new class of diode pumped alkali vapor lasers (DPALs) offers high efficiency cw laser beams at wavelengths which efficiently couple to photovoltaic (PV) cells: silicon cells at 895 nm (cesium), and GaAs cells at 795 nm (rubidium) and at 770 nm (potassium). DPAL electrical efficiencies of 25-30% are projected, enabling PV cell efficiencies {approx}40% (Si) and {approx}60% (GaAs). Near-diffraction-limited DPAL device power scaling into the multi-kilowatt regime from a single aperture is projected.

  3. Two novel low-power and high-speed dynamic carbon nanotube full-adder cells

    Directory of Open Access Journals (Sweden)

    Eshghi Mohammad

    2011-01-01

    Full Text Available Abstract In this paper, two novel low-power and high-speed carbon nanotube full-adder cells in dynamic logic style are presented. Carbon nanotube field-effect transistors (CNFETs are efficient in designing a high performance circuit. To design our full-adder cells, CNFETs with three different threshold voltages (low threshold, normal threshold, and high threshold are used. First design generates SUM and COUT through separate transistors, and second design is a multi-output dynamic full adder. Proposed full adders are simulated using HSPICE based on CNFET model with 0.9 V supply voltages. Simulation result shows that the proposed designs consume less power and have low power-delay product compared to other CNFET-based full-adder cells.

  4. Power Harvesting from Human Serum in Buckypaper-Based Enzymatic Biofuel Cell

    Directory of Open Access Journals (Sweden)

    Güray eGüven

    2016-02-01

    Full Text Available The requirement for a miniature, high density, long life, rechargeable power source is common to a vast majority of microsystems, including the implantable devices for medical applications. A model biofuel cell system operating in human serum has been studied for future applications of biomedical and implantable medical devices. Anodic and cathodic electrodes were made of carbon nanotube –buckypaper modified with PQQ-dependent glucose dehydrogenase and laccase, respectively. Modified electrodes were characterized electrochemically and assembled in a biofuel cell set-up. Power density of 16.12 μW/cm2 was achieved in human serum for lower than physiological glucose concentrations. Increasing the glucose concentration and biofuel cell temperature caused an increase on power output leading up to 49.16 μW/cm2.

  5. Generating electricity from biofluid with a nanowire-based biofuel cell for self-powered nanodevices

    Energy Technology Data Exchange (ETDEWEB)

    Pan, Caofeng; Wu, Hui; Ahmad, Mashkoor; Luo, Zhixiang; Xie, Jianbo; Yan, Xinxu; Wu, Lihua; Zhu, Jing [Beijing National Center for Electron Microscopy, Laboratory of Advanced Materials, State Key Laboratory of New Ceramics and Fine Processing, Department of Material Science and Engineering, Tsinghua University, Beijing 100084 (China); The National Center for Nanoscience and Technology (NCNST) of China, Beijing 100080 (China); Fang, Ying; Li, Qiang [The National Center for Nanoscience and Technology (NCNST) of China, Beijing 100080 (China); Wang, Zhong Lin [School Materials Science and Engineering, Georgia Institute of Technology, Atlanta Georgia 30332-0245 (United States)

    2010-12-14

    We report a nanowire-based biofuel cell based on a single proton conductive polymer nanowire for converting chemical energy from biofluids, such as glucose/blood, into electricity, with glucose oxidase and laccase as catalyst. The glucose is supplied from the biofluid, the nanowire serves as the proton conductor, and the whole cell can be realized at the nano/micrometer scale. The biofuel cell composed of a single nanowire generates an output power as high as 0.5-3 {mu}W, and it has been integrated with a set of nanowire-based sensors for performing self-powered sensing. This study shows the feasibility of building self-powered nanodevices for the biological sciences, environmental monitoring, defense technology, and even personal electronics. (Copyright copyright 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  6. Small proton exchange membrane fuel cell power station by using bio-hydrogen

    Institute of Scientific and Technical Information of China (English)

    刘志祥; 毛宗强; 王诚; 任南琪

    2006-01-01

    In fermentative organic waste water treatment process, there was hydrogen as a by-product. After some purification,there was about 50% ~ 70% hydrogen in the bio-gas, which could be utilized for electricity generation with fuel cell. Half a year ago, joint experiments between biological hydrogen production in Harbin Institute of Technology (HIT) and proton exchange membrane fuel cell (PEMFC) power station in Tsinghua University were conducted for electricity generation with bio-hydrogen from the pilot plant in HIT. The results proved the feasibility of the bio-hydrogen as a by-product utilization with PEMFC power station and revealed some problems of fuel cell power station for this application.

  7. Assessment of a potential rapid condensation induced water hammer in a passive auxiliary feedwater system

    International Nuclear Information System (INIS)

    A passive auxiliary feedwater system (PAFS) which is incorporated in the APR+ system is a kind of closed natural circulation loop. The PAFS has no operating functions during normal plant operation, but it has a dedicated safety function of the residual heat removal following initiating events, including the unlikely event of the most limiting single failure occurring coincident with a loss of offsite power, when the feedwater system becomes inoperable or unavailable. Even in the unlikely event of a station blackout, the isolation valves can be opened either by DC power or manual operation and then the PAFS can also provide adequate condensate to the steam generator (SG). The PAFS piping in the vicinity of each of the two SGs is designed to minimize the potential for destructive water hammer during start up operation by setting the stroke time for full close or full open of the condensate isolation valves upon receipt of a passive auxiliary feedwater actuation signal. The temperature of the stagnant condensate water and its surrounding tubes and piping during the reactor normal operation modes may fall to the ambient temperature. A possible concern is the introduction of saturated steam into the PAFS recirculation pipe downstream of the PCHX in the beginning of the PAFS operation. Although the steam introduction rate is expected to be slow, a rapid condensation rate is expected due to the initial cold surrounding temperature in the pipe, which could result in a localized pressure reduction and the propagation of decompression and velocity disturbances into the condensate water leg, which might cause the sudden closure of check valves and associated water hammer. Thus, it is requisite for the licensing review of the PAFS design to confirm if destructive water hammers will not be produced due to such rapid condensation induced decompressions in the system. This paper addresses an assessment of the potential local decompressions which could result from the steam

  8. Assessment of a potential rapid condensation induced water hammer in a passive auxiliary feedwater system

    Energy Technology Data Exchange (ETDEWEB)

    Jo, Jong Chull; Shin, Byung Soo; Do, Kyu Sik [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of); Moody, Frederick J. [General Electric (Retired), CA (United States)

    2012-10-15

    A passive auxiliary feedwater system (PAFS) which is incorporated in the APR+ system is a kind of closed natural circulation loop. The PAFS has no operating functions during normal plant operation, but it has a dedicated safety function of the residual heat removal following initiating events, including the unlikely event of the most limiting single failure occurring coincident with a loss of offsite power, when the feedwater system becomes inoperable or unavailable. Even in the unlikely event of a station blackout, the isolation valves can be opened either by DC power or manual operation and then the PAFS can also provide adequate condensate to the steam generator (SG). The PAFS piping in the vicinity of each of the two SGs is designed to minimize the potential for destructive water hammer during start up operation by setting the stroke time for full close or full open of the condensate isolation valves upon receipt of a passive auxiliary feedwater actuation signal. The temperature of the stagnant condensate water and its surrounding tubes and piping during the reactor normal operation modes may fall to the ambient temperature. A possible concern is the introduction of saturated steam into the PAFS recirculation pipe downstream of the PCHX in the beginning of the PAFS operation. Although the steam introduction rate is expected to be slow, a rapid condensation rate is expected due to the initial cold surrounding temperature in the pipe, which could result in a localized pressure reduction and the propagation of decompression and velocity disturbances into the condensate water leg, which might cause the sudden closure of check valves and associated water hammer. Thus, it is requisite for the licensing review of the PAFS design to confirm if destructive water hammers will not be produced due to such rapid condensation induced decompressions in the system. This paper addresses an assessment of the potential local decompressions which could result from the steam

  9. The use of power gyrator structures as energy processing cells in photovoltaic solar facilities

    OpenAIRE

    Martínez García, Herminio

    2014-01-01

    This paper will provide a classification of high efficiency switching power-gyrator structures and their use as cells for energy processing in photovoltaic solar facilities. Having into account the properties of these topologies presented in the article, their inclusion in solar facilities allows increasing the performance of the whole installation. Thus, the design, simulation and implementation of a G-type power gyrator are carried out throughout the text. In addition, in order to obtain th...

  10. Power gyrator structures and their use as cells for energy-processing in photovoltaic solar facilities

    OpenAIRE

    Martínez García, Herminio; Grau Saldes, Antoni; Bolea Monte, Yolanda

    2012-01-01

    This paper provides a classification of high efficiency switching power-gyrator structures and their use as cells for energy processing in photovoltaic solar facilities. Having into account the properties of these topologies presented in the article, their inclusion in solar facilities allows increasing the performance of the whole installation. Thus, the design, simulation and implementation of a G-type power gyrator are carried out throughout the text. In addition, in order to obtain ...

  11. Using CMOS Sub-Micron Technology VLSI Implementation of Low Power, High Speed SRAM Cell and DRAM Cell

    Directory of Open Access Journals (Sweden)

    Viplav A. Soliv

    2012-01-01

    Full Text Available Abstract This paper deals with the design and analysis of high speed Static Random Access Memory (SRAM cell and Dynamic Random Access Memory (DRAM cell to develop low power consumption. SRAM and DRAM cells have been the predominant technologies used to implement memory cells in computer systems, each one having its advantages and shortcomings. SRAM cells are faster and require no refresh since reads are not destructive. In contrast, DRAM cells provide higher density and minimal leakage energy. Here we use 12-transistor SRAM cell built from a simple static latch and tri state inverter. The reading action itself refreshes the content of memory. The SRAM access path is split into two portions: from address input to word line rise (the row decoder and from word line rise to data output (the read data path. The decoder which constitutes the path from address input to the word line rise is implemented as a binary structure by implementing a multi-stage path. The key to low power operation in the SRAM data path is to reduce the signal swings on the high capacitance nodes like the bit lines and the data lines.

  12. Structure and Control Strategies of Fuel Cell Vehicle

    Institute of Scientific and Technical Information of China (English)

    宋建国; 张承宁; 孙逢春; 钟秋海

    2004-01-01

    The structure and kinds of the fuel cell vehicle (FCV) and the mathematical model of the fuel cell processor are discussed in detail. FCV includes many parts: the fuel cell thermal and water management, fuel supply, air supply and distribution, AC motor drive, main and auxiliary power management, and overall vehicle control system. So it requires different kinds of control strategies, such as the PID method, zero-pole method, optimal control method, fuzzy control and neural network control. Along with the progress of control method, the fuel cell vehicle's stability and reliability is up-and-up. Experiment results show FCV has high energy efficiency.

  13. Comment: ``On the computation of molecular auxiliary functions and ”

    Indian Academy of Sciences (India)

    Frank E Harris

    2003-10-01

    Guseinov, Mamedov, Kara and Orbay (Pramana – J. Phys. 56, 691 (2001)) propose methods for evaluating the molecular auxiliary functions () and () for the range 17 ≤ ≤ 60 and 25 ≤ ≤ 60. However, their procedure for () is not new, and that for () is less efficient for their target range than another well-known method. Their approach does have merit for smaller non-zero values of . Two minor errors in table 1 of their paper are also identified.

  14. System design impacts on optimization of the advanced radioisotope power system (ARPS) AMTEC cell

    International Nuclear Information System (INIS)

    Several NASA deep space missions require Advanced Radioisotope Power Systems (ARPS) to supply spacecraft power for various internal functions and mission instruments and experiments. AMTEC (Alkali-Metal Thermal-Electric Conversion) power conversion is the DOE-selected technology for an advanced, next- generation RPS to power these spacecraft. Advanced Modular Power Systems, Inc. (AMPS) has begun investigating the design of an AMTEC-based ARPS using the General Purpose Heat Source (GPHS) and the latest PX-5 AMTEC cell technology with refractory materials in critical components. This paper presents and discusses the system design methodology, and results of important system design tradeoffs and system design impacts on the ARPS AMTEC cell design. This work investigated dual 2-GPHS system configurations and 4-GPHS system configurations with 16 side-mounted AMTEC cells operating at beginning-of-mission (BOM) and end-of-mission (EOM) GPHS heat dissipation conditions. Current design studies indicate using a refractory material AMTEC cell with 8-BASE tubes, 5.0 inches long, and 1.75 inches diameter in the 4-GPHS system configuration is the strongest design candidate to satisfy system performance requirements

  15. Wearable Sensor System Powered by a Biofuel Cell for Detection of Lactate Levels in Sweat

    Science.gov (United States)

    Garcia, S. O.; Ulyanova, Y. V.; Figueroa-Teran, R.; Bhatt, K. H.; Singhal, S.; Atanassov, P.

    2016-01-01

    An NAD+-dependent enzymatic sensor with biofuel cell power source system for non-invasive monitoring of lactate in sweat was designed, developed, and tested. The sensor component, based on lactate dehydrogenase, showed linear current response with increasing lactate concentrations with limits of detection from 5 to 100 mM lactate and sensitivity of 0.2 µA.mM−1 in the presence of target analyte. In addition to the sensor patch a power source was also designed, developed and tested. The power source was a biofuel cell designed to oxidize glucose via glucose oxidase. The biofuel cell showed excellent performance, achieving over 80 mA at 0.4 V (16 mW) in a footprint of 3.5 × 3.5 × 0.7 cm. Furthermore, in order to couple the sensor to the power source, system electronic components were designed and fabricated. These consisted of an energy harvester (EH) and a micropotentiostat (MP). The EH was employed for harvesting power provided by the biofuel cell as well as up-converting the voltage to 3.0 V needed for the operation of the MP. The sensor was attached to MP for chronoamperometric detection of lactate. The Sensor Patch System was demonstrated under laboratory conditions.

  16. Design of a low energy reaction cell for distributed power applications

    International Nuclear Information System (INIS)

    Power units using Low Energy Nuclear Reactions (LENRs) potentially offer a radical new approach to power units that could provide distributed power units in the 1- 50 kW range. As described in an ICONE-8 paper (Miley, et al. 2000-c), these cells employ thin metallic film cathodes (order of 500.10-10 m, using variously Ni, Pd and Ti) with electrolytes such as 0.5-1 molar lithium sulfate in light water. Power densities exceeding 10 W/cc in the films have been achieved. An ultimate goal is to incorporate this thin-film technology into a 'tightly packed' cell design where the film material occupies ∼20% of the total volume. If this is achieved, power densities of ∼20 W/cm3 appear feasible, opening the way to a number of potential applications involving distributed power. In the present paper, prior work is briefly reviewed, and the design of a cell employing integrated electrode and solid-state electrical-conversion systems is described along with some recent experimental results. (authors)

  17. Power Management Optimization of an Experimental Fuel Cell/Battery/Supercapacitor Hybrid System

    Directory of Open Access Journals (Sweden)

    Farouk Odeim

    2015-06-01

    Full Text Available In this paper, an experimental fuel cell/battery/supercapacitor hybrid system is investigated in terms of modeling and power management design and optimization. The power management strategy is designed based on the role that should be played by each component of the hybrid power source. The supercapacitor is responsible for the peak power demands. The battery assists the supercapacitor in fulfilling the transient power demand by controlling its state-of-energy, whereas the fuel cell system, with its slow dynamics, controls the state-of-charge of the battery. The parameters of the power management strategy are optimized by a genetic algorithm and Pareto front analysis in a framework of multi-objective optimization, taking into account the hydrogen consumption, the battery loading and the acceleration performance. The optimization results are validated on a test bench composed of a fuel cell system (1.2 kW, 26 V, lithium polymer battery (30 Ah, 37 V, and a supercapacitor (167 F, 48 V.

  18. Near-term markets for PEM fuel cell power modules: industrial vehicles and hydrogen recovery

    International Nuclear Information System (INIS)

    'Full text:' Nuvera Fuel Cells, Inc. is a global leader in the development and advancement of multifuel processing and fuel cell technology. With offices located in Italy and the USA, Nuvera is committed to advancing the commercialization of hydrogen fuel cell power modules for industrial vehicles and equipment and stationary applications by 2006, natural gas fuel cell power systems for cogeneration applications by 2007, and on-board gasoline fuel processors and fuel cell stacks for automotive applications by 2010. Nuvera Fuel Cells Europe is ISO 9001:2000 certified for 'Research, Development, Design, Production and Servicing of Fuel Cell Stacks and Fuel Cell Systems.' In the chemical industry, one of the largest operating expenses today is the cost of electricity. For example, caustic soda and chlorine are produced today using industrial membrane electrolysis which is an energy intensive process. Production of 1 metric ton of caustic soda consumes 2.5 MWh of energy. However, about 20% of the electricity consumed can be recovered by converting the hydrogen byproduct of the caustic soda production process into electricity via PEM fuel cells. The accessible market is a function of the economic value of the hydrogen whether flared, used as fuel, or as chemical. Responding to this market need, we are currently developing large hydrogen fuel cell power modules 'Forza' that use excess hydrogen to produce electricity, representing a practical economic alternative to reducing the net electricity cost. Due for commercial launch in 2006, Forza is a low-pressure, steady state, base-load power generation solution that will operate at high efficiency and 100% capacity over a 24-hour period. We believe this premise is also true for chemical and electrochemical plants and companies that convert hydrogen to electricity using renewable sources like windmills or hydropower. The second near-term market that Nuvera is developing utilizes a 5.5 kW hydrogen fueled power module 'H2e' for

  19. Secondary electric power generation with minimum engine bleed

    Science.gov (United States)

    Tagge, G. E.

    1983-01-01

    Secondary electric power generation with minimum engine bleed is discussed. Present and future jet engine systems are compared. The role of auxiliary power units is evaluated. Details of secondary electric power generation systems with and without auxiliary power units are given. Advanced bleed systems are compared with minimum bleed systems. A cost model of ownership is given. The difference in the cost of ownership between a minimum bleed system and an advanced bleed system is given.

  20. Numerical Investigation of Thermal Effect in Plasma Electrode Pockels Cell for High Average Power

    Institute of Scientific and Technical Information of China (English)

    CAO Ding-Xiang; ZHANG Xiong-Jun; ZHENG Wan-Guo; HE Shao-Bo; SUI Zhan

    2006-01-01

    @@ The average power of a Pockels cell is limited by thermal effects arising from the optical absorption of the laser pulse. These thermal effects can be managed by configuring the switch as a plasma-electrode thin plate Pockels cell, which works under heat-capacity operation. Simulation results show that, based on KD*P (in thickness 0.5cm) at an average power loading of 1 kW, the aperture integrated depolarization loss at 1.06 um is less than 10% in 5min working time.