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Sample records for 3mw power level

  1. 2.3-MW Medium-Voltage, Three-Level Wind Energy Inverter Applying a Unique Bus Structure and 4.5-kV Si/SiC Hybrid Isolated Power Modules: Preprint

    Erdman, W.; Keller, J.; Grider, D.; VanBrunt, E.

    2014-11-01

    A high-efficiency, 2.3-MW, medium-voltage, three-level inverter utilizing 4.5-kV Si/SiC (silicon carbide) hybrid modules for wind energy applications is discussed. The inverter addresses recent trends in siting the inverter within the base of multimegawatt turbine towers. A simplified split, three-layer laminated bus structure that maintains low parasitic inductances is introduced along with a low-voltage, high-current test method for determining these inductances. Feed-thru bushings, edge fill methods, and other design features of the laminated bus structure provide voltage isolation that is consistent with the 10.4-kV module isolation levels. Inverter efficiency improvement is a result of the (essential) elimination of the reverse recovery charge present in 4.5-kV Si PIN diodes, which can produce a significant reduction in diode turn-off losses as well as insulated-gate bipolar transistor (IGBT) turn-on losses. The hybrid modules are supplied in industry-standard 140 mm x 130 mm and 190 mm x 130 mm packages to demonstrate direct module substitution into existing inverter designs. A focus on laminated bus/capacitor-bank/module subassembly level switching performance is presented.

  2. Energy Storage System by Means of Improved Thermal Performance of a 3 MW Grid Side Wind Power Converter

    Qin, Zian; Liserre, Marco; Blaabjerg, Frede

    2013-01-01

    method of the energy storage system. Then the conventional thermal evaluation approach is simplified for evaluation with long term wind profile. The case studies are done to address the optimal power size and capacity of the energy storage system by comparing the improvement of the thermal performance......Wind speed variations make the power of wind turbine system to fluctuate, which could increase the thermal stress of the power converter and reduce its lifetime. In order to relieve this problem, short-term energy storage technologies are applied to improve the thermal performance of a 3 MW grid...... side wind power converter. The cost, weight and cycle life of the energy storage technologies are evaluated based on a typical low speed high turbulence wind profile. In detail, a wind turbine system model is established and its control strategy is illustrated, which is followed by the power control...

  3. Reliability Estimation with Uncertainties Consideration for High Power IGBTs in 2.3 MW Wind Turbine Converter System

    Kostandyan, Erik; Ma, Ke

    2012-01-01

    This paper investigates the lifetime of high power IGBTs (insulated gate bipolar transistors) used in large wind turbine applications. Since the IGBTs are critical components in a wind turbine power converter, it is of great importance to assess their reliability in the design phase of the turbin...

  4. Characterization of blade throw from a 2.3MW horizontal axis wind turbine upon failure

    Sarlak, Hamid; Sørensen, Jens Nørkær

    2015-01-01

    The present work concerns aerodynamics of thrown objects from a 2.3 MW Horizontal Axis Wind Turbine (HAWT), as a consequence of blade failure. The governing set of ordinary differential equations for the flying objects are derived and numerically solved using a 4th order Runge-Kutta time advancin...

  5. Race-track coils for a 3 MW HTS ship motor

    Ueno, E., E-mail: ueno-eisaku@sei.co.jp; Kato, T.; Hayashi, K.

    2014-09-15

    Highlights: • Sumitomo Electric manufactured the HTS field coils for a 3 MW HTS ship motor. • The motor was developed and successfully passed the loading test by Kawasaki Heavy. • We tested and obtained the basic data to evaluate the 20-year durability of coils. - Abstract: Since the discovery of high-temperature superconductivity (HTS), Sumitomo Electric has been developing silver-sheathed Bi2223 superconducting wire and products. Ship propulsion motors are one of the most promising applications of HTS. Sumitomo Electric Industries, Ltd. (SEI) has recently manufactured 24 large racetrack coils, using 70 km long DI-BSCCO wires, for use in a 3 MW HTS motor developed by Kawasaki Heavy Industries, Ltd. (KHI). The 3 MW HTS motor, using our newly developed racetrack coils, has successfully passed the loading test. It is particularly important that the HTS field coils used in ship propulsion motors can withstand the expansive forces repeatedly applied to them. As racetrack type coils have straight sections, the support mechanism they require to withstand expansive forces is very different from that of circular coils. Therefore, we ran tests and obtained the basic data to evaluate the 20-year durability of racetrack coils against the repeatedly applied expansive forces expected in domestic ship propulsion motors.

  6. Level Shifter Design for Low Power Applications

    Manoj Kumar

    2010-10-01

    Full Text Available With scaling of Vt sub-threshold leakage power is increasing and expected to become significant part oftotal power consumption.In present work three new configurations of level shifters for low powerapplication in 0.35μm technology have been presented. The proposed circuits utilize the merits ofstacking technique with smaller leakage current and reduction in leakage power. Conventional levelshifter has been improved by addition of three NMOS transistors, which shows total power consumptionof 402.2264pW as compared to 0.49833nW with existing circuit. Single supply level shifter has beenmodified with addition of two NMOS transistors that gives total power consumption of 108.641pW ascompared to 31.06nW. Another circuit, contention mitigated level shifter (CMLS with three additionaltransistors shows total power consumption of 396.75pW as compared to 0.4937354nW. Three proposedcircuit’s shows better performance in terms of power consumption with a little conciliation in delay.Output level of 3.3V has been obtained with input pulse of 1.6V for all proposed circuits.

  7. Race-track coils for a 3 MW HTS ship motor

    Ueno, E.; Kato, T.; Hayashi, K.

    2014-09-01

    Since the discovery of high-temperature superconductivity (HTS), Sumitomo Electric has been developing silver-sheathed Bi2223 superconducting wire and products. Ship propulsion motors are one of the most promising applications of HTS. Sumitomo Electric Industries, Ltd. (SEI) has recently manufactured 24 large racetrack coils, using 70 km long DI-BSCCO wires, for use in a 3 MW HTS motor developed by Kawasaki Heavy Industries, Ltd. (KHI). The 3 MW HTS motor, using our newly developed racetrack coils, has successfully passed the loading test. It is particularly important that the HTS field coils used in ship propulsion motors can withstand the expansive forces repeatedly applied to them. As racetrack type coils have straight sections, the support mechanism they require to withstand expansive forces is very different from that of circular coils. Therefore, we ran tests and obtained the basic data to evaluate the 20-year durability of racetrack coils against the repeatedly applied expansive forces expected in domestic ship propulsion motors.

  8. Model Predictive Wind Turbine Control with Move-Blocking Strategy for Load Alleviation and Power Leveling

    Jassmann, U.; Dickler, S.; Zierath, J.; Hakenberg, M.; Abel, D.

    2016-09-01

    This contribution presents a Model Predictive Controller (MPC) with moveblocking strategy for combined power leveling and load alleviation in wind turbine operation with a focus on extreme loads. The controller is designed for a 3 MW wind turbine developed by W2E Wind to Energy GmbH and compared to a baseline controller, using a classic control scheme, which currently operates the wind turbine. All simulations are carried out with a detailed multibody simulation turbine model implemented in alaska/Wind. The performance of the two different controllers is compared using a 50-year Extreme Operation Gust event, since it is one of the main design drivers for the wind turbine considered in this work. The implemented MPC is able to level electrical output power and reduce mechanical loads at the same time. Without de-rating the achieved control results, a move-blocking strategy is utilized and allowed to reduce the computational burden of the MPC by more than 50% compared to a baseline MPC implementation. This even allows to run the MPC on a state of the art Programmable Logic Controller.

  9. Low Power Design with High-Level Power Estimation and Power-Aware Synthesis

    Ahuja, Sumit; Shukla, Sandeep Kumar

    2012-01-01

    Low-power ASIC/FPGA based designs are important due to the need for extended battery life, reduced form factor, and lower packaging and cooling costs for electronic devices. These products require fast turnaround time because of the increasing demand for handheld electronic devices such as cell-phones, PDAs and high performance machines for data centers. To achieve short time to market, design flows must facilitate a much shortened time-to-product requirement. High-level modeling, architectural exploration and direct synthesis of design from high level description enable this design process. This book presents novel research techniques, algorithms,methodologies and experimental results for high level power estimation and power aware high-level synthesis. Readers will learn to apply such techniques to enable design flows resulting in shorter time to market and successful low power ASIC/FPGA design. Integrates power estimation and reduction for high level synthesis, with low-power, high-level design; Shows spec...

  10. Power Analysis in Two-Level Unbalanced Designs

    Konstantopoulos, Spyros

    2010-01-01

    Previous work on statistical power has discussed mainly single-level designs or 2-level balanced designs with random effects. Although balanced experiments are common, in practice balance cannot always be achieved. Work on class size is one example of unbalanced designs. This study provides methods for power analysis in 2-level unbalanced designs…

  11. Analysis of superconducting microstrip resonator at various microwave power levels

    Srivastava, G.P.; Jacob, M.V.; Jayakumar, M.; Bhatnagar, P.K. [Department of Electronic Science, University of Delhi, South Campus, Benito Juarez Road, New Delhi 110021 (India); Kataria, N.D. [National Physical Laboratory, K. S. Krishnan Road, New Delhi 110 012 (India)

    1997-05-01

    The real and imaginary parts of the surface impedance of YBCO superconductors have been studied at different microwave power levels. Using the relations for the critical current density and the grain boundary resistance, a relation for calculating the power dependence of the surface resistance has been obtained. Also, a relation to find the resonant frequency of a superconducting microstrip resonator at various input power levels has been derived. Measurements have been carried out on various microstrip resonators to study the variation of surface resistance and resonant frequency at different rf power levels. The experimental results are in good agreement with theoretical results. {copyright} {ital 1997 American Institute of Physics.}

  12. Reactive Power Impact on Lifetime Prediction of Two-level Wind Power Converter

    Zhou, Dao; Blaabjerg, Frede; Lau, M.;

    2013-01-01

    The influence of reactive power injection on the dominating two-level wind power converter is investigated and compared in terms of power loss and thermal behavior. Then the lifetime of both the partial-scale and full-scale power converter is estimated based on the widely used Coffin-Manson model....... It is concluded that the injection of the reactive power could have serious impact on the power loss and thermal profile, especially at lower wind speed. Furthermore, the introduction of the reactive power could also shorten the lifetime of the wind power converter significantly....

  13. Challenges with Tertiary-Level Mechatronic Fluid Power

    Dransfield, Peter; Conrad, Finn

    1996-01-01

    As authors we take the view that mechatronics, as it relates to fluid power, has three levels which we designate as primary, secondary and tertiary. A brief review of the current status of fluid power, hydraulic and pneumatic, and of electronic control of it is presented and discussed. The focus...... is then on tertiary-level mechatronic fluid power and the challenges to it being applied successfully....

  14. Experimental Study of a Multi Level Overtopping Wave Power Device

    Kofoed, Jens Peter; Hald, Tue; Frigaard, Peter Bak

    2002-01-01

    Results of experimental investigations of a floating wave energy device called Power Pyramid is presented. The Power Pyramid utilizes reservoirs in multiple levels when capturing wave overtopping and converting it into electrical energy. The effect of capturing the overtopping in multiple levels......, compared to only one level, has been evaluated experimentally. From the experimental results, and the performed optimizations based on these, it has been found that the efficiency of a wave power device of the overtopping type can be increased by as much as 76 % by using 5 levels instead of 1. However...

  15. Rotational Augmentation on a 2.3 MW Rotor Blade with Thick Flatback Airfoil Cross-Sections: Preprint

    Schreck, S.; Fingersh, L.; Siegel, K.; Singh, M.; Medina, P.

    2013-01-01

    Rotational augmentation was analyzed for a 2.3 MW wind turbine, which was equipped with thick flatback airfoils at inboard radial locations and extensively instrumented for acquisition of time varying surface pressures. Mean aerodynamic force and surface pressure data were extracted from an extensive field test database, subject to stringent criteria for wind inflow and turbine operating conditions. Analyses of these data showed pronounced amplification of aerodynamic forces and significant enhancements to surface pressures in response to rotational influences, relative to two-dimensional, stationary conditions. Rotational augmentation occurrence and intensity in the current effort was found to be consistent with that observed in previous research. Notably, elevated airfoil thickness and flatback design did not impede rotational augmentation.

  16. Locational Marginal Pricing in the Campus Power System at the Power Distribution Level

    Hao, Jun; Gu, Yi; Zhang, Yingchen; Zhang, Jun Jason; Gao, David Wenzhong

    2016-11-14

    In the development of smart grid at distribution level, the realization of real-time nodal pricing is one of the key challenges. The research work in this paper implements and studies the methodology of locational marginal pricing at distribution level based on a real-world distribution power system. The pricing mechanism utilizes optimal power flow to calculate the corresponding distributional nodal prices. Both Direct Current Optimal Power Flow and Alternate Current Optimal Power Flow are utilized to calculate and analyze the nodal prices. The University of Denver campus power grid is used as the power distribution system test bed to demonstrate the pricing methodology.

  17. K3MW METAR

    National Oceanic and Atmospheric Administration, Department of Commerce — METAR is a routine scheduled observation and is the primary observation code used in the United States to satisfy requirements for reporting surface meteorological...

  18. Use of existing standards to measure sound power levels of powered hand tools-necessary revisions

    Hayden, Charles S.; Zechmann, Edward

    2005-09-01

    At recent NOISE-CON and Acoustical Society of America meetings, noise rating labeling was discussed as a way of manufacturers providing full disclosure information for their noise emitting products. The first step is to gather sound power level data from these products. Sound power level data should be gathered in accordance with existing ANSI and/or ISO standards. Some standards, such as ANSI 12.15, may not define true operational noise emissions[r1] and thus may provide inaccurate information when that information is used to choose a hearing protection device or used to make a purchasing decision. A number of standards were systematically combined by NIOSH researchers to provide the most accurate information on sound power levels of powered hand tools used in the construction industry. This presentation will detail some of the challenges of existing ANSI 12.15 (and draft ANSI 12.41) to measure sound power levels of electric (and pneumatic) powered hand tools.

  19. Power Consideration for Three-Level Growth Models

    Li, Wei; Konstantopoulos, Spyros

    2016-01-01

    The purpose of this study is extend previous methods by Raudenbush and Liu (2001) and Spybrook et al. (2011), and provide methods for power analysis of tests of treatment effects in studies of polynomial change with two levels of nesting (e.g., students and schools) where the treatment is either at the third level (e.g., school intervention) or at…

  20. Thawing of foods in a microwave oven: I. Effect of power levels and power cycling.

    Chamchong, M; Datta, A K

    1999-01-01

    Microwave thawing is faster than other methods, but it can produce significant non-uniformity of heating. The objective of this study was to perform comprehensive experimentation and heat transfer modeling to relate the time to thaw and the non-uniformity of thawing to power cycling, power level and the surface heat transfer coefficient. The governing energy equation was formulated with an exponential decay of the microwave flux from the surface. Surface microwave flux was obtained from the measured temperature rise using inverse heat transfer analysis. Gradual phase change was formulated as an apparent specific heat, and was obtained for the experimental material tylose from differential scanning calorimetry (DSC) measurements. The temperatures were measured immediately following heating with a fast response thermocouple. Dielectric properties were measured above freezing. Results show that the microwave flux at the surface and its decay are affected by the changes in the power level. Power cycling has an almost identical effect as continuous power at the reduced level of the average cycled power. As power level increases, the surface flux increases by the same fraction. At higher power levels, however, the outside thaws relatively faster. A "shield" develops due to a much reduced microwave penetration depth at the surface. This thawing time at higher power levels is reduced considerably. Temperature increases initially are non-uniform since the surface is heated at a faster rate than the interior. In keeping with the assumption that once the temperature reaches 100 degrees C, all energy absorbed goes into evaporation, and subsequent temperature is maintained at 100 degrees C. Thus, eventually, non-uniformity starts to decrease.

  1. Battery Energy Storage System for PV Output Power Leveling

    Rajkiran Singh

    2014-01-01

    Full Text Available Fluctuating photovoltaic (PV output power reduces the reliability in power system when there is a massive penetration of PV generators. Energy storage systems that are connected to the PV generators using bidirectional isolated dc-dc converter can be utilized for compensating the fluctuating PV power. This paper presents a grid connected energy storage system based on a 2 kW full-bridge bidirectional isolated dc-dc converter and a PWM converter for PV output power leveling. This paper proposes two controllers: a current controller using the d-q synchronous reference and a phase-shift controller. The main function of the current controller is to regulate the voltage at the high-side dc, so that the voltage ratio of the high-voltage side (HVS with low-voltage side (LVS is equal to the transformer turns ratio. The phase-shift controller is employed to manage the charging and discharging modes of the battery based on PV output power and battery voltage. With the proposed system, unity power factor and efficient active power injection are achieved. The feasibility of the proposed control system is investigated using PSCAD simulation.

  2. Aerobic Capacity and Anaerobic Power Levels of the University Students

    Taskin, Cengiz

    2016-01-01

    The aim of study was to analyze aerobic capacity and anaerobic power levels of the university students. Total forty university students who is department physical education and department business (age means; 21.15±1.46 years for male and age means; 20.55±1.79 years for female in department physical education), volunteered to participate in this…

  3. Design of megawatt power level heat pipe reactors

    Mcclure, Patrick Ray [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Poston, David Irvin [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Dasari, Venkateswara Rao [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Reid, Robert Stowers [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-11-12

    An important niche for nuclear energy is the need for power at remote locations removed from a reliable electrical grid. Nuclear energy has potential applications at strategic defense locations, theaters of battle, remote communities, and emergency locations. With proper safeguards, a 1 to 10-MWe (megawatt electric) mobile reactor system could provide robust, self-contained, and long-term power in any environment. Heat pipe-cooled fast-spectrum nuclear reactors have been identified as a candidate for these applications. Heat pipe reactors, using alkali metal heat pipes, are perfectly suited for mobile applications because their nature is inherently simpler, smaller, and more reliable than “traditional” reactors. The goal of this project was to develop a scalable conceptual design for a compact reactor and to identify scaling issues for compact heat pipe cooled reactors in general. Toward this goal two detailed concepts were developed, the first concept with more conventional materials and a power of about 2 MWe and a the second concept with less conventional materials and a power level of about 5 MWe. A series of more qualitative advanced designs were developed (with less detail) that show power levels can be pushed to approximately 30 MWe.

  4. Protoflight photovoltaic power module system-level tests in the space power facility

    Rivera, Juan C.; Kirch, Luke A.

    1989-01-01

    Work Package Four, which includes the NASA-Lewis and Rocketdyne, has selected an approach for the Space Station Freedom Photovoltaic (PV) Power Module flight certification that combines system level qualification and acceptance testing in the thermal vacuum environment: The protoflight vehicle approach. This approach maximizes ground test verification to assure system level performance and to minimize risk of on-orbit failures. The preliminary plans for system level thermal vacuum environmental testing of the protoflight PV Power Module in the NASA-Lewis Space Power Facility (SPF), are addressed. Details of the facility modifications to refurbish SPF, after 13 years of downtime, are briefly discussed. The results of an evaluation of the effectiveness of system level environmental testing in screening out incipient part and workmanship defects and unique failure modes are discussed. Preliminary test objectives, test hardware configurations, test support equipment, and operations are presented.

  5. Fractional-power-law level statistics due to dynamical tunneling.

    Bäcker, Arnd; Ketzmerick, Roland; Löck, Steffen; Mertig, Normann

    2011-01-14

    For systems with a mixed phase space we demonstrate that dynamical tunneling universally leads to a fractional power law of the level-spacing distribution P(s) over a wide range of small spacings s. Going beyond Berry-Robnik statistics, we take into account that dynamical tunneling rates between the regular and the chaotic region vary over many orders of magnitude. This results in a prediction of P(s) which excellently describes the spectral data of the standard map. Moreover, we show that the power-law exponent is proportional to the effective Planck constant h(eff).

  6. Functional Level Power Analysis: An Efficient Approach for Modeling the Power Consumption of Complex Processors

    2004-01-01

    A high-level consumption estimation methodology and its associated tool, SoftExplorer, are presented. The estimation methodology uses a functional modeling of the processor combined with a parametric model to allow the designer to estimate the power consumption when the embedded software is executed on the target. SoftExplorer uses as input the assembly code generated by the compiler; its efficiency is compared to SimplePower's approach. Results for different processors (TI C62, C67, C55 and ...

  7. Device for timing and power level setting for microwave applications

    Ursu, M.-P.; Buidoş, T.

    2016-08-01

    Nowadays, the microwaves are widely used for various technological processes. The microwaves are emitted by magnetrons, which have strict requirements concerning power supplies for anode and filament cathodes, intensity of magnetic field, cooling and electromagnetic shielding. The magnetrons do not tolerate any alteration of their required voltages, currents and magnetic fields, which means that their output microwave power is fixed, so the only way to alter the power level is to use time-division, by turning the magnetron on and off by repetitive time patterns. In order to attain accurate and reproducible results, as well as correct and safe operation of the microwave device, all these requirements must be fulfilled. Safe, correct and reproducible operation of the microwave appliance can be achieved by means of a specially built electronic device, which ensures accurate and reproducible exposure times, interlocking of the commands and automatic switch off when abnormal operating conditions occur. This driving device, designed and realized during the completion of Mr.Ursu's doctoral thesis, consists of a quartz time-base, several programmable frequency and duration dividers, LED displays, sensors and interlocking gates. The active and passive electronic components are placed on custom-made PCB's, designed and made by means of computer-aided applications and machines. The driving commands of the electronic device are delivered to the magnetron power supplies by means of optic zero-passing relays. The inputs of the electronic driving device can sense the status of the microwave appliance. The user is able to enter the total exposure time, the division factor that sets the output power level and, as a novelty, the clock frequency of the time divider.

  8. SEVEN LEVEL CONTROL OF SHUNT ACTIVE POWER FILTER FOR POWER QUALITY ENHANCEMENT

    G. JAYAKRISHNA

    2011-09-01

    Full Text Available Shunt Active Power Filter (SAPF is one of the controllers to enhance power quality (PQ. This paper presents Hybrid Cascaded Seven-Level Inverter (HCSLI used in SAPF to compensate reactive power, improve the power factor and to suppress the total harmonic distortion (THD in supply current due to linear load and Non- Linear Diode Rectifier Loads (NLDRLs.In this paper d-q reference frame theory for reference current computation, Constant Switching Frequency Multicarrier Sub-Harmonic Pulse Width Modulation (CSFMSHPWM technique for controlling the switches of HCSLI, Fuzzy logic controller (FLC for regulating dc side capacitor voltage are proposed. The results are validated through simulation using Mat Lab/simulink with and without SAPF for linear and nonlinear loads.

  9. Sound power and vibration levels for two different piano soundboards

    Squicciarini, Giacomo; Valiente, Pablo Miranda; Thompson, David J.

    2016-09-01

    This paper compares the sound power and vibration levels for two different soundboards for upright pianos. One of them is made of laminated spruce and the other of solid spruce (tone-wood). These differ also in the number of ribs and manufacturing procedure. The methodology used is defined in two major steps: (i) acoustic power due to a unit force is obtained reciprocally by measuring the acceleration response of the piano soundboards when excited by acoustic waves in reverberant field; (ii) impact tests are adopted to measure driving point and spatially-averaged mean-square transfer mobility. The results show that, in the midhigh frequency range, the soundboard made of solid spruce has a greater vibrational and acoustic response than the laminated soundboard. The effect of string tension is also addressed, showing that is only relevant at low frequencies.

  10. Technical basis for staffing levels at nuclear power plants

    Shurberg, D.A.; Haber, S.B. [Brookhaven National Lab., Upton, NY (United States); Morisseau, D. [Nuclear Regulatory Commission, Washington, DC (United States)] [and others

    1995-04-01

    The objective of this project is to provide a technical basis for the establishment of criteria for minimum staffing levels of licensed and non-licensed NPP shift personnel. Minimum staffing levels for the purpose of this study, are defined as those necessary for successful accomplishment of all safety and additional functions that must be performed in order for the licensee to meet applicable regulatory requirements. This project involves a multi-faceted approach to the investigation of the issue. Relevant NRC documentation was identified and reviewed. Using the information obtained from this documentation review, a test plan was developed to aid in the collection of further information regarding the adequacy of current shift staffing levels. The test plan addresses three different activities to be conducted to provide information to the NRC for use in the assessment of current minimum staffing levels. The first activity is collection of data related to industry shift staffing practices through site visits to seven nuclear power plants. The second activity is a simulator study, which will use licensed operator crews responding to a simulated event, under two different staffing levels. Finally, workload models will be constructed for both licensed and non-licensed personnel, using a priori knowledge of the simulator scenarios with data resulting from one of the staffing levels studied in the simulator, and the data collected from the site visits. The model will then be validated against the data obtained from the second staffing level studied in the simulator. The validated model can then be used to study the impact of changing staffing-related variables on the plant shift crew`s ability to effectively mitigate an event.

  11. Power estimation on functional level for programmable processors

    M. Schneider

    2004-01-01

    Full Text Available In diesem Beitrag werden verschiedene Ansätze zur Verlustleistungsschätzung von programmierbaren Prozessoren vorgestellt und bezüglich ihrer Übertragbarkeit auf moderne Prozessor-Architekturen wie beispielsweise Very Long Instruction Word (VLIW-Architekturen bewertet. Besonderes Augenmerk liegt hierbei auf dem Konzept der sogenannten Functional-Level Power Analysis (FLPA. Dieser Ansatz basiert auf der Einteilung der Prozessor-Architektur in funktionale Blöcke wie beispielsweise Processing-Unit, Clock-Netzwerk, interner Speicher und andere. Die Verlustleistungsaufnahme dieser Bl¨ocke wird parameterabhängig durch arithmetische Modellfunktionen beschrieben. Durch automatisierte Analyse von Assemblercodes des zu schätzenden Systems mittels eines Parsers können die Eingangsparameter wie beispielsweise der erzielte Parallelitätsgrad oder die Art des Speicherzugriffs gewonnen werden. Dieser Ansatz wird am Beispiel zweier moderner digitaler Signalprozessoren durch eine Vielzahl von Basis-Algorithmen der digitalen Signalverarbeitung evaluiert. Die ermittelten Schätzwerte für die einzelnen Algorithmen werden dabei mit physikalisch gemessenen Werten verglichen. Es ergibt sich ein sehr kleiner maximaler Schätzfehler von 3%. In this contribution different approaches for power estimation for programmable processors are presented and evaluated concerning their capability to be applied to modern digital signal processor architectures like e.g. Very Long InstructionWord (VLIW -architectures. Special emphasis will be laid on the concept of so-called Functional-Level Power Analysis (FLPA. This approach is based on the separation of the processor architecture into functional blocks like e.g. processing unit, clock network, internal memory and others. The power consumption of these blocks is described by parameter dependent arithmetic model functions. By application of a parser based automized analysis of assembler codes of the systems to be estimated

  12. Retrieval of Intermediate Level Waste at Trawsfyndd Nuclear Power Station

    Wall, S.; Shaw, I.

    2002-02-25

    In 1996 RWE NUKEM Limited were awarded two contracts by BNFL Magnox Generation as part of the decommissioning programme for the Trawsfynydd power station. From the normal operations of the two Magnox reactors, intermediate level waste (ILW) had accumulated on site, this was Miscellaneous Activated Components (MAC) and Fuel Element Debris (FED). The objective of these projects is retrieval of the waste from storage vaults, monitoring, packaging and immobilization in a form suitable for on site storage in the medium term and eventual disposal to a waste repository. The projects involve the design, supply, commissioning and operation of equipment to retrieve, pack and immobilize the waste, this includes recovery from vaults in both reactor and pond locations and final decommissioning and removal of plant from site after completion of waste recovery.

  13. Application of Doubly-fed Induction Motor in 3 MW Gearbox Test Bench%双馈电机在3MW齿轮箱试验台中的应用

    张乐

    2011-01-01

    在分析同步电机、双馈电机的特性基础上,提出了一种采用双馈电机对拖的方式来实现3 MW齿轮箱的试验方法.采用2台双馈电机和1台变频电机进行控制,变频电机控制试验台的速度以及补偿试验台的功率损耗,分别控制双馈电机转子的电流和频率来达到控制负载功率的目的.该方法具有良好的控制精度、高效节能,投资成本低.%On the base of analyzing features of synchronous motor and doubly-fed induction motor, a method which is used to complete the test of 3 MW gearbox by dragging two doubly-fed induction generators themselves was brought forward. This method uses two doubly-fed induction motors and a variable-frequency motor to control. The variable-frequency motor controls the speed of test bench and equalizes the power losses of test bench. The current and frequency of doubly-fed induction motor's rotor are controlled to control the load power. This method has a excellence control accuracy, is energy-efficient and low investment cost.

  14. Low-Carbon Based Multi-Objective Bi-Level Power Dispatching under Uncertainty

    2016-01-01

    This research examines a low-carbon power dispatch problem under uncertainty. A hybrid uncertain multi-objective bi-level model with one leader and multiple followers is established to support the decision making of power dispatch and generation. The upper level decision maker is the regional power grid corporation which allocates power quotas to each follower based on the objectives of reasonable returns, a small power surplus and low carbon emissions. The lower level decision makers are the...

  15. Comparison of leachable trace element levels in coal gasifier ash with levels in power plant ash

    Bombaugh, K.J.; Milosavljevic, M.; Janes, T.K.

    1984-04-01

    The levels of 14 trace elements in leachates from three types of ash of a common origin coal were compared. The study was conducted over a one year period at the Kosovo plant in Obilic, Yugoslavia comparing coal gasifier ash with fly ash and bottom ash from a coal-fired power plant using lignite from the Dobro Solo mine. Results obtained indicate that levels of Sb, As, Be, Cr, Cu, Pb, Mo, Ni and Zn in gasifier ash leachate were similar to those in fly ash leachate. Barium levels in gasifier ash leachate averaged 2.7 times that in fly ash and selenium levels averaged 0.33 times. The average ratio for the total set was 0.99. The set average, relative to bottom ash, was 2.1 with the nickel ratio differing significantly from the average. Metal oxides, CaO, MgO, Na/SUB/2O, K/SUB/2O and MgO; in the Kosovo gasifier ash were found at levels similar to those in Kosovo fly ash, and except for K/SUB/2O, were approximately twice those in bottom ash. Concentration levels of all components showed relatively small variations averaging 50% of their mean annual concentration over the test period. (14 refs.)

  16. A Rotating Speed Controller Design Method for Power Levelling by Means of Inertia Energy in Wind Power Systems

    Qin, Zian; Blaabjerg, Frede; Loh, Poh Chiang

    2015-01-01

    Power fluctuation caused by wind speed variations may be harmful for the stability of the power system as well as the reliability of the wind power converter, since it may induce thermal excursions in the solder joints of the power modules. Using the wind turbine rotor inertia energy for power...... leveling has been studied before, but no quantified analysis or generic design method have been found. In this paper, the transfer functions from the wind speed to electrical power, electromagnetic torque, and rotating speed are built based on which the rotating speed controller is designed...

  17. Power Constrained High-Level Synthesis of Battery Powered Digital Systems

    Nielsen, Sune Fallgaard; Madsen, Jan

    2003-01-01

    of utmost importance for battery powered embedded systems. Our approach extends the partial-clique partitioning algorithm by introducing power awareness through a heuristic algorithm which bounds the design space to those of power feasible schedules. We have applied our algorithm on a set of dataflow graphs...

  18. Cognitive Aspects of Power in a Two-Level Game

    Juvina, Ion; Lebiere, Christian; Martin, Jolie; Gonzalez, Cleotilde

    The Intergroup Prisoner's Dilemma with Intragroup Power Dynamics (IPD^2) is a new game paradigm for studying human behavior in conflict situations. IPD^2 adds the concept of intragroup power to an intergroup version of the standard Iterated Prisoner's Dilemma game. We conducted an exploratory laboratory study in which individual human participants played the game against computer strategies of various complexities. We also developed a cognitive model of human decision making in this game. The model was run in place of the human participant under the same conditions as in the laboratory study. Results from the human study and the model simulations are presented and discussed, emphasizing the value of including intragroup power in game theoretic models of conflict.

  19. Module-Level Power Converters For Parallel Connected Photovoltaic Arrays

    2012-01-01

    Secondary Bare Wire Area Rs Secondary Resistance Ps Secondary Copper Loss Pcu Total Copper Loss W/kg Watts Per Kilogram Pfe Core Loss PΣ Total...material properties of the chosen core [30]. The calculated core loss power density was was 17.2712 W/kg. The core loss, Pfe , was calculated

  20. The development of a milliwatt-level radioisotope power source

    Bugby, David C.; McBirney, Thomas R.

    1998-01-01

    Future NASA spacecraft for unmanned planetary exploration will be much smaller and require much less power than the large systems used in prior missions. The ``Powerstick'', a miniaturized isotopic electrical power generator, uses a flight-qualified, DoE-manufactured, 1.1 W Radioisotope Heater Unit (RHU) to generate the high temperature sink for a thermoelectric converter (TEC). The TEC generates sufficient electrical power (~40 mW) to trickle-charge an external rechargeable battery pack, which can then be used in low duty cycle, low power applications. The original Powerstick concept (proposed by JPL) was refined at Swales Aerospace (SA), which has: repackaged it, constructed a prototype, and performed limited testing. The prototype Powerstick is 63.5 mm (2.500'') in diameter, 76.2 mm (3.000'') long, and weighs about 0.3 kg (0.66 lb). Structural analysis indicates the Powerstick can easily survive typical launch loads. Thermal analysis indicates that over 70% of the RHU energy enters the TEC. This paper will describe the design and analysis of the Powerstick prototype and present the key test results.

  1. The advantages and disadvantages of centralized control of air power at operational level

    Arisoy, Uǧur

    2014-05-01

    People do not want to see and hear a war. In today's world, if war is inevitable, the use of air power is seen as the preferable means of conducting operations instead of financially burdensome land battles which are more likely to cause heavy loss of life. The use of Air Power has gained importance in NATO operations in the Post-Cold War era. For example, air power has undertaken a decisive role from the beginning to the end of the operation in Libya. From this point of view, the most important issue to consider is how to direct air power more effectively at operational level. NATO's Core JFAC (Joint Force Air Command) was established in 2012 to control joint air power at operational level from a single center. US had experienced JFAC aproach in the Operation Desert Storm in 1991. UK, France, Germany, Italy and Spain are also directing their air power from their JFAC structures. Joint air power can be directed from a single center at operational level by means of JFAC. JFAC aproach provides complex planning progress of Air Power to be controled faster in a single center. An Air Power with a large number of aircrafts, long range missiles of cutting-edge technology may have difficulties in achieving results unless directed effectively. In this article, directing air power more effectively at operational level has been studied in the framework of directing air power from a single center carried out by SWOT analysis technique. "Directing Air Power at operational level from a single center similar to JFAC-like structure" is compared with "Directing Air Power at operational level from two centers similar to AC (Air Command) + CAOC (Combined Air Operations Center) structure" As a result of this study, it is assessed that directing air power at operational level from a single center would bring effectiveness to the air campaign. The study examines directing air power at operational level. Developments at political, strategic and tactical levels have been ignored.

  2. Photovoltaic Shading Testbed for Module-Level Power Electronics

    Deline, C.; Meydbray, J.; Donovan, M.; Forrest, J.

    2012-05-01

    This document describes a repeatable test procedure that attempts to simulate shading situations, as would be experienced by typical residential rooftop photovoltaic (PV) systems. This type of shading test is particularly useful to evaluate the impact of different power conversion setups, including microinverters, DC power optimizers and string inverters, on overall system performance. The performance results are weighted based on annual estimates of shade to predict annual performance improvement. A trial run of the test procedure was conducted with a side by side comparison of a string inverter with a microinverter, both operating on identical 8kW solar arrays. Considering three different shade weighting conditions, the microinverter was found to increase production by 3.7% under light shading, 7.8% under moderate shading, and 12.3% under heavy shading, relative to the reference string inverter case. Detail is provided in this document to allow duplication of the test method at different test installations and for different power electronics devices.

  3. On the Wind Stress - Sea Level Power Law.

    1983-06-01

    The response of coastal sea level to local forcing by synpotic scale winds is usually assumed to be linear in wind stress . However, the response of...response to wind stress may allow significant improvement in the analysis of some sea-level problems. (Author)

  4. Design of Oil-Quenching Tank for 3 MW Wind Turbine Main Shaft Bearings%3MW风电主轴轴承淬火油槽设计

    邵阳; 马忠超; 姚艳书

    2015-01-01

    The problems existing in heat treatment for main shaft bearings used in 3MW wind turbines are analyzed.The volume of oil-quenching tank for the bearing rings is calculated,and the structure for oil-quenching tank is rede-signed.The hardness of the bearing rings satisfies standard requirement for secondary quenching cooling process during heat treatment by adopting oil-quenching tank with top plug type and side plug type stirrers.%分析3MW风电主轴轴承热处理中存在的问题,计算轴承套圈淬火油槽的体积,重新设计淬火油槽结构,采用顶插式和侧插式组合搅拌器的淬火油槽,使3MW风电主轴轴承在热处理二次淬火冷却过程中硬度达到标准要求。

  5. Toward the Next Level of PCB Usage in Power Electronic Converters

    De Jong, E.C.W.; Ferreira, B.J.A.; Bauer, P.

    2008-01-01

    A means for power electronics to exploit the level of 3-D packaging already being implemented in compact consumer products, such as digital cameras, is investigated in order to increase its power density. The increase in functionality and usage of printed circuit board (PCB) in power electronic conv

  6. Power Analysis for Cross Level Mediation in CRTs

    Kelcey, Ben

    2014-01-01

    A common design in education research for interventions operating at a group or cluster level is a cluster randomized trial (CRT) (Bloom, 2005). In CRTs, intact clusters (e.g., schools) are assigned to treatment conditions rather than individuals (e.g., students) and are frequently an effective way to study interventions because they permit…

  7. ACCOUNTING OF REACTIVE POWER COMPENSATION LEVEL AT PAYMENT CALCULATION OF TECHNOLOGICAL CONSUMPTION (LOSSES OF ELECTRIC POWER FOR ITS TRANSMISSION IN POWER NETWORK

    E. P. Zabello

    2005-01-01

    Full Text Available The method is proposed to make a correction in payment for consumption of reactive energy and power which is attributed to deviation of actual activation energy losses for reactive power compensation from their standard value. It is recommended to calculate standard loss values for every voltage level and actual loss values are to be determined with the help of application of remote electronic accounting means in the current mode of power consumption.

  8. The far-reaching effects of power: at the individual, dyadic, and group levels

    Galinsky, A.D.; Chou, E.Y.; Halevy, N.; Van Kleef, G.A.; Neale, M.A.; Mannix, E.A.

    2012-01-01

    Purpose - This chapter provides a framework that captures the fundamental impacts of power at the individual, dyadic, small group, and organizational levels. Within each level, we trace the psychological, cognitive, and behavioral consequences of having or lacking power. Approach - We integrate theo

  9. Power levels in office equipment: Measurements of new monitors and personal computers

    Roberson, Judy A.; Brown, Richard E.; Nordman, Bruce; Webber, Carrie A.; Homan, Gregory H.; Mahajan, Akshay; McWhinney, Marla; Koomey, Jonathan G.

    2002-05-14

    Electronic office equipment has proliferated rapidly over the last twenty years and is projected to continue growing in the future. Efforts to reduce the growth in office equipment energy use have focused on power management to reduce power consumption of electronic devices when not being used for their primary purpose. The EPA ENERGY STAR[registered trademark] program has been instrumental in gaining widespread support for power management in office equipment, and accurate information about the energy used by office equipment in all power levels is important to improving program design and evaluation. This paper presents the results of a field study conducted during 2001 to measure the power levels of new monitors and personal computers. We measured off, on, and low-power levels in about 60 units manufactured since July 2000. The paper summarizes power data collected, explores differences within the sample (e.g., between CRT and LCD monitors), and discusses some issues that arise in m etering office equipment. We also present conclusions to help improve the success of future power management programs.Our findings include a trend among monitor manufacturers to provide a single very low low-power level, and the need to standardize methods for measuring monitor on power, to more accurately estimate the annual energy consumption of office equipment, as well as actual and potential energy savings from power management.

  10. The Power of Individual-level Drivers of Inventive Performance

    Zwick, Thomas; Frosch, Katharina; Hoisl, Karin

    2017-01-01

    We combine two lines of research on inventive and creative performance that have been separated before. We use empirical models of the performance of inventors over their careers based on an established theoretical framework of the drivers of creativity, the Knowledge, Skills, Abilities, and Othe......, technology, patent, and time information. We show that educational level, skills acquired during the career, personality traits, career motivation, cognitive ability, and cognitive problem-solving style are significantly related to inventive performance....

  11. Operating the Irish power system with increased levels of wind power

    Tuohy, A.; Denny, E.; Meibom, Peter

    2008-01-01

    This paper summarises some of the main impacts of large amounts of wind power installed in the island of Ireland. Using results from various studies performed on this system, it is shown that wind power will impact on all time frames, from seconds to daily planning of the system operation. Results...... from studies examining operation of the system with up to approximately 40% of electricity provided by wind show that some of the most important aspects to be considered include the type of wind turbine technology, the provision of reserve to accommodate wind forecasting error and the method used...

  12. Impact of CDMA wireless phone power output and puncture rate on hearing aid interference levels.

    Fry, T L; Schlegel, R E; Grant, H

    2000-01-01

    Interference between digital wireless phones and hearing aids occurs when the radiofrequency bursts from the phone transmission are demodulated by the hearing aid amplifier. The amplified interference signal is heard as a "buzz" or "static" by the hearing aid wearer. Most research and standards development activity has focused on worst-case scenarios with the phone operating at its maximum power. Since this power level is often not typical in urban and suburban settings, it is of value to determine the impact of lower power levels on the overall level of audible interference. Using a frequency analyzer, and several hearings aids and code division multiple access (CDMA) phones, the audio frequency spectrum of interference was recorded for each phone-aid combination and for a range of power levels producing from no interference to maximum interference. As phone power is increased, the interference signal becomes distinguishable from the ambient noise level and a linear response region is observed in which a specified increase in power output results in a proportional increase in the overall input referenced interference level (OIRIL). As power is increased beyond the linear region, the hearing aid enters a saturation region where an additional power increase results in a reduction or no increase in the OIRIL. The numeric differences in interference documented in this study were used in conjunction with the results of a previous study by the authors to determine the impact of reduced power on speech intelligibility and annoyance. The amount of improvement for a given power reduction depends on the radiofrequency immunity of the hearing aid and is substantial for hearing aids with poor immunity. For high-immunity aids, the level of audible interference remains low even at high phone power levels.

  13. Heat Balance Research on 3MW Marine Wind Turbine's Engine Room%3MW海上风力发电机机舱热平衡设计

    周年勇; 蒋彦龙; 刘志丽; 康娜

    2011-01-01

    According to the analysis of engine room structure and heat-dissipating of different components and environmental operating requirements of 3MW Wind Turbine System, heat balance design of Wind Turbine's engine room is carried out. Then calculation method of the heat load of engine room including the components heat load,outside heat load and fresh air heat load are proposed. At the same time,heat load changing characteristics of the engine room is obtained under the cooling method of jetting and influence of factors such as air temperature and speed and gray scale of the engine room to heat balance of the cabin is researched. This work could be helpful for the optimization of large-capacity Wind Turbine's cooling system.%以3MW海上风力发电机为研究对象,在考察其机舱布置结构、主要部件散热情况及环境要求的基础上,对机舱进行了热平衡设计,建立了机舱热平衡方程;提出了舱内部件载荷、机舱内外对流换热系数、舱内正压维持新风量的计算方法;获得了射流冷却方式下的舱内热载荷变化特性;并研究了舱内外空气温度、速度、舱体表面灰度等因素对机舱热平衡的影响.研究工作对于大容量风力发电冷却系统的设计优化具有参考价值.

  14. Design and Analysis of Multi Level D-STATCOM to Improve the Power Quality

    Dinesh. Badavath,

    2014-01-01

    Full Text Available In the last decade, the electrical power quality issue has been the main concern of the power companies. Power quality is defined as the index which both the delivery and consumption of electric power affect on the performance of electrical apparatus. From a customer point of view, a power quality problem can be defined as any problem is manifested on voltage, current, or frequency deviation that results in power failure. The power electronics progressive, especially in flexible alternating-current transmission system (FACTS and custom power devices, affects power quality improvement. This paper presents an investigation of seven-Level Cascaded H - bridge (CHB Inverter as Distribution Static Compensator (DSTATCOM in Power System (PS for compensation of reactive power and harmonics. The advantages of CHB inverter are low harmonic distortion, reduced number of switches and suppression of switching losses. The DSTATCOM helps to improve the power factor and eliminate the Total Harmonics Distortion (THD drawn from a Non-Liner Diode Rectifier Load (NLDRL. The D-Q reference frame theory is used to generate the reference compensating currents for DSTATCOM while Proportional and Integral (PI control is used for capacitor dc voltage regulation. A CHB Inverter is considered for shunt compensation of a 11 Kv distribution system. Finally a level shifted PWM (LSPWM and phase shifted PWM (PSPWM techniques are adopted to investigate the performance of CHB Inverter. The results are obtained through Matlab/Simulink software package.

  15. Optimization of the Electric Power Leveling System Using a Superconducting Magnetic Energy Storage with Genetic Algorithm

    Funabiki, Shigeyuki; Tanaka, Toshihiko; Fujii, Toshinori

    A new optimization method of the electric power leveling system using an SMES is proposed. The SMES is parallelly connected with rolling mills in steel works. The leveling control is based on fuzzy reasoning. The SMES capacity and the scaling factors of the fuzzy controller will be optimized so that the power leveling control can be achieved and then the total cost of the added SMES cost and reduced contract electricity rate becomes lower. The optimization is carried out using the genetic algorithm and the cost reduction of 7.76 billion yen can be achieved. It is confirmed by the power leveling simulation that the proposed optimization method is very effective for designing the power leveling system.

  16. System Level Power Optimization of Digital Audio Back End for Hearing Aids

    Pracny, Peter; Jørgensen, Ivan Harald Holger; Bruun, Erik

    2016-01-01

    the interpolation filter and the SD modulator on the system level so that the switching frequency of the Class D PA - the main power consumer in the back end - is minimized. A figure-of-merit (FOM) which allows judging the power consumption of the digital part of the back end early in the design process is used...... to track the hardware and power demands as the tradeoffs of the system level parameters are investigated. The result is the digital part of the back end optimized with respect to power which provides audio performance comparable to state-of-theart. A combination of system level parameters leading...... to the lowest switching frequency of the Class D power amplifier reported in literature for the SD modulatorbased back end is derived using this approach....

  17. The Level of Power Quality Measurement and Evaluation in A Stone Crusher Plant

    Mustafa ŞEKKELİ

    2009-03-01

    Full Text Available Both electric utilities and end users of electric power are becoming increasingly concerned about the quality of electric power. Quality of electrical energy in the electrical system that is requested continuous power (uninterrupted power, constant frequency and with constant amplitude can be explained by sinusoidal voltage. Deformation of voltage in the form of sinusoidal waveform is explained as a harmonic. Harmonics are most important factors in decreasing quality of energy in the electrical system. In industrial plants, existence of harmocins and voltage drop, causes serious problems both in plant and network. This problem affects the cost. In this study, a power quality measurements are carried out in stone crusher plant. Harmonics and voltage drop has been measured and evaluated with the power analyzer. In the power quality measurements, harmonic level of the plant is not so bad. However, it is recommended that compensation system with harmonic elimination can be established in plant.

  18. Optimization of Electric Power Leveling Systems by a Novel Cluster-Structured GA with Masking

    Itoh, Jyunpei; Fujii, Toshinori; Funabiki, Shigeyuki

    Power fluctuations of the rolling mill may cause the instability of electric power systems, and increase the cost of the electric power facility and electricity charges. Therefore, in order to compensate the power fluctuations, the development of the electric power-leveling systems (EPLS) is very important in the future electric power system. The EPLS with a SMES has been proposed as one of the countermeasures for the electric power quality improvement. However, the SMES is very expensive and it is difficult to decide the gains of the controller. It is essential in the practical use that the reduction of SMES capacity is realized. This paper proposes a new optimization method of the EPLS. The proposed algorithm is Cluster-Structured GA with Masking (CSGA). The optimization of the EPLS can be achieved by the proposed CSGA compared to the GA.

  19. Transmission Power Measurements for Wireless Sensor Nodes and their Relationship to the Battery Level

    Blom, S.; Bellettini, C.; Sinigalliesi, A.; Stabellini, L.; Rossi, M.; Mazzini, G.

    2005-01-01

    In this work we focus on the new generation EYESIFXv2 [1] wireless sensor nodes by carrying out experimental measurements on power related quantities. In particular, our aim is to characterize the relationship between the level of the battery and the transmission power radiated by the node. The pres

  20. Building America Case Study: Photovoltaic Systems with Module-Level Power Electronics

    2015-09-01

    Direct current (DC) power optimizers and microinverters (together known as module-level power electronics, or MLPE) are one of the fastest growing market segments in the solar industry. According to GTM Research in The Global PV Inverter Landscape 2015, over 55% of all residential photovoltaic (PV) installations in the United States used some form of MLPE in 2014.

  1. A Fast Approach for System-Level Power Modeling and Simulation

    XIAJun; ZOUXuecheng

    2004-01-01

    Power is one of the main constraints in SOC (System-on-a-chip) design. System-level power modeling and simulation help to reduce the power dissipation in early stage. But by reason of the variability of system architecture, the amount of simulation is vast which result in the simulation time is unacceptable. On the basis of previous work, a modified hybrid approach for core-based system-level power modeling is proposed in this paper, which enables SOC designers to estimate system power consumption under different core parameters and just simulates the system only once. Thereafter designers can make a trade-off rapidly between performance characters (such as power, area, speed and test, etc) and make a decision about which architecture is the best solution to implement system functionality. The key of our approach is to help the core designers to provide a power metric function to the core users and the effectiveness and efficiency of our approach hinge on whether the IP provider could provide an accurate power model of each core. A linear model is chosen to describe the relationship between power consumption and parameters and least-square-error is selected as the optimization criterion to mitigate error. Although the power is given as an example, our approach can be applied to speed and area performance trade-off also because speed and area performance modeling is simpler relatively.

  2. Bidirectional Five-Level Power Processing Interface for Low Voltage Battery Energy Storage System

    Huang, Jain-Yi; Jou, Hurng-Liahng; Wu, Kuen-Der; Lin, You-Si; Wu, Jinn-Chang

    A bidirectional five-level power processing interface for low voltage battery energy storage system (BESS) is developed in this paper. This BESS consists of a bidirectional five-level DC-AC converter, a bidirectional dual boost/buck DC-DC converter and a battery set. This five-level DC-AC converter includes a bidirectional full-bridge converter and a bidirectional dual buck DC-DC converter. The five-level power processing interface can charge power to the battery set form the utility or discharge the power from the battery set to the utility depending on the demanded operation of user. A hardware prototype is developed to verify the performance of this BESS. Experimental results show the performance of the developed BESS is as expected.

  3. Low-Carbon Based Multi-Objective Bi-Level Power Dispatching under Uncertainty

    Xiaoyang Zhou

    2016-06-01

    Full Text Available This research examines a low-carbon power dispatch problem under uncertainty. A hybrid uncertain multi-objective bi-level model with one leader and multiple followers is established to support the decision making of power dispatch and generation. The upper level decision maker is the regional power grid corporation which allocates power quotas to each follower based on the objectives of reasonable returns, a small power surplus and low carbon emissions. The lower level decision makers are the power generation groups which decide on their respective power generation plans and prices to ensure the highest total revenue under consideration of government subsidies, environmental costs and the carbon trading. Random and fuzzy variables are adopted to describe the uncertain factors and chance constrained and expected value programming are used to handle the hybrid uncertain model. The bi-level models are then transformed into solvable single level models using a satisfaction method. Finally, a detailed case study and comparative analyses are presented to test the proposed models and approaches to validate the effectiveness and illustrate the advantages.

  4. Output power levels from mobile phones in different geographical areas; implications for exposure assessment

    Lonn, S; Forssen, U; P. Vecchia; Ahlbom, A; Feychting, M

    2004-01-01

    Background: The power level used by the mobile phone is one of the most important factors determining the intensity of the radiofrequency exposure during a call. Mobile phone calls made in areas where base stations are densely situated (normally urban areas) should theoretically on average use lower output power levels than mobile phone calls made in areas with larger distances between base stations (rural areas).

  5. Thermal analysis of multi-MW two-level wind power converter

    Zhou, Dao; Blaabjerg, Frede; Mogens, Lau; Tonnes, Michael

    2012-01-01

    In this paper, the multi-MW wind turbine of partial-scale and full-scale two-level power converter with DFIG and direct-drive PMSG are designed and compared in terms of their thermal performance. Simulations of different configurations regarding loss distribution and junction temperature in the power device in the whole range of wind speed are presented and analyzed. It is concluded that in both partial-scale and full-scale power converter the most thermal stressed power device in the generat...

  6. Lifetime Estimation of Electrolytic Capacitors in Fuel Cell Power Converter at Various Confidence Levels

    Zhou, Dao; Wang, Huai; Blaabjerg, Frede

    2016-01-01

    DC capacitors in power electronic converters are a major constraint on improvement of the power density and the reliability. In this paper, according to the degradation data of tested capacitors, the lifetime model of the component is analyzed at various confidence levels. Then, the mission profile...... based lifetime expectancy of the individual capacitor and the capacitor bank is estimated in a fuel cell backup power converter operating in both standby mode and operation mode. The lifetime prediction of the capacitor banks at different confidence levels is also obtained....

  7. Power Spectrum Analysis and Missing Level Statistics of Microwave Graphs with Violated Time Reversal Invariance

    Białous, Małgorzata; Yunko, Vitalii; Bauch, Szymon; Ławniczak, Michał; Dietz, Barbara; Sirko, Leszek

    2016-09-01

    We present experimental studies of the power spectrum and other fluctuation properties in the spectra of microwave networks simulating chaotic quantum graphs with violated time reversal invariance. On the basis of our data sets, we demonstrate that the power spectrum in combination with other long-range and also short-range spectral fluctuations provides a powerful tool for the identification of the symmetries and the determination of the fraction of missing levels. Such a procedure is indispensable for the evaluation of the fluctuation properties in the spectra of real physical systems like, e.g., nuclei or molecules, where one has to deal with the problem of missing levels.

  8. Lifetime Estimation of Electrolytic Capacitors in Fuel Cell Power Converter at Various Confidence Levels

    Zhou, Dao; Wang, Huai; Blaabjerg, Frede

    2016-01-01

    DC capacitors in power electronic converters are a major constraint on improvement of the power density and the reliability. In this paper, according to the degradation data of tested capacitors, the lifetime model of the component is analyzed at various confidence levels. Then, the mission profi...... based lifetime expectancy of the individual capacitor and the capacitor bank is estimated in a fuel cell backup power converter operating in both standby mode and operation mode. The lifetime prediction of the capacitor banks at different confidence levels is also obtained....

  9. Modular Multi-level converter based HVDC System for Grid Connection of Offshore Wind Power Plant

    Gnanarathna, U.N.; Chaudhary, Sanjay Kumar; Gole, A.M.;

    2010-01-01

    This paper explores the application of modular multi-level converters (MMC) as a means for harnessing the power from off-shore wind power plants. The MMC consists of a large number of simple voltage sourced converter (VSC) submodules that can be easily assembled into a converter for high......-voltage and high power. The paper shows that the MMC converter has a fast response and low harmonic content in comparison with a two-level VSC option. The paper discusses the modeling approach used, including a solution to the modeling challenge imposed by the very large number of switching devices in the MMC....

  10. The Level of Difficulty and Discrimination Power of the Basic Knowledge and Skills Examination (EXHCOBA.

    Eduardo Backhoff Escudero

    2000-05-01

    Full Text Available The Basic Knowledge and Skills Examination (EXHCOBA is one of the few great-scale examinations in Mexico which has been publishing its psychometric parameters.  In this paper we describe the  item analysis results, regarding the exam’s difficulty level and discrimination power.  Results show that most of the items have a medium difficulty and a high discrimination power.  They also reveal that the mathematics items have better discrimination power levels than the ones which belong to social science.

  11. System-level Reliability Assessment of Power Stage in Fuel Cell Application

    Zhou, Dao; Wang, Huai; Blaabjerg, Frede

    2016-01-01

    High efficient and less pollutant fuel cell stacks are emerging and strong candidates of the power solution used for mobile base stations. In the application of the backup power, the availability and reliability hold the highest priority. This paper considers the reliability metrics from...... the component-level to the system-level for the power stage used in a fuel cell application. It starts with an estimation of the annual accumulated damage for the key power electronic components according to the real mission profile of the fuel cell system. Then, considering the parameter variations in both...... reliability. In a case study of a 5 kW fuel cell power stage, the parameter variations of the lifetime model prove that the exponential factor of the junction temperature fluctuation is the most sensitive parameter. Besides, if a 5-out-of-6 redundancy is used, it is concluded both the B10 and the B1 system...

  12. Power level effects on thorium-based fuels in pressure-tube heavy water reactors

    Bromley, B.P.; Edwards, G.W.R., E-mail: blair.bromley@cnl.ca [Canadian Nuclear Laboratories, Chalk River, Ontario (Canada); Sambavalingam, P. [Univ. of Ontario Inst. of Technology, Oshawa, Ontario (Canada)

    2016-06-15

    Lattice and core physics modeling and calculations have been performed to quantify the impact of power/flux levels on the reactivity and achievable burnup for 35-element fuel bundles made with Pu/Th or U-233/Th. The fissile content in these bundles has been adjusted to produce on the order of 20 MWd/kg burnup in homogeneous cores in a 700 MWe-class pressure-tube heavy water reactor, operating on a once-through thorium cycle. Results demonstrate that the impact of the power/flux level is modest for Pu/Th fuels but significant for U-233/Th fuels. In particular, high power/flux reduces the breeding and burnup potential of U-233/Th fuels. Thus, there may be an incentive to operate reactors with U-233/Th fuels at a lower power density or to develop alternative refueling schemes that will lower the time-average specific power, thereby increasing burnup.(author)

  13. Power estimation for intellectual property-based digital systems at the architectural level

    Yaseer Arafat Durrani

    2014-09-01

    We present an efficient power macro-modeling technique at the architectural level for digital electronic systems. This technique estimates the power dissipation of intellectual property (IP components to their statistical knowledge of the primary inputs/outputs. During the power estimation method, the sequence of an input stream is generated by a genetic algorithm (GA using input metrics and the macro-model function to construct a set of functions that map the input metrics of a macro-block to its output metrics. Then, a Monte Carlo zero-delay simulation is performed and the power dissipation is predicted by a macro-model function. The most important contribution of the technique is that it allows fast power estimation of IP-based design by the simple addition of individual power consumption. This makes the power modeling of SoCs an easy task that permits evaluation of power features at the architectural level. In order to evaluate our model, we have constructed IP-based digital systems using different IP macro-blocks. In experiments with an individual IP macro-block the average error is 1–2% and for an entire IP-based system with interconnects, the error range is from 9% to 15%. The preliminary results are effective and our macro-model provides accurate power estimation.

  14. Scalability of components for kW-level average power few-cycle lasers.

    Hädrich, Steffen; Rothhardt, Jan; Demmler, Stefan; Tschernajew, Maxim; Hoffmann, Armin; Krebs, Manuel; Liem, Andreas; de Vries, Oliver; Plötner, Marco; Fabian, Simone; Schreiber, Thomas; Limpert, Jens; Tünnermann, Andreas

    2016-03-01

    In this paper, the average power scalability of components that can be used for intense few-cycle lasers based on nonlinear compression of modern femtosecond solid-state lasers is investigated. The key components of such a setup, namely, the gas-filled waveguides, laser windows, chirped mirrors for pulse compression and low dispersion mirrors for beam collimation, focusing, and beam steering are tested under high-average-power operation using a kilowatt cw laser. We demonstrate the long-term stable transmission of kW-level average power through a hollow capillary and a Kagome-type photonic crystal fiber. In addition, we show that sapphire substrates significantly improve the average power capability of metal-coated mirrors. Ultimately, ultrabroadband dielectric mirrors show negligible heating up to 1 kW of average power. In summary, a technology for scaling of few-cycle lasers up to 1 kW of average power and beyond is presented.

  15. Four-level time decomposition quasi-static power flow and successive disturbances analysis. [Power system disturbances

    Jovanovic, S.M. (Nikola Tesla Inst., Belgrade (YU))

    1990-01-01

    This paper presents a model and an appropriate numerical procedure for a four-level time decomposition quasi-static power flow and successive disturbances analysis of power systems. The analysis consists of the sequential computation of the zero, primary, secondary and tertiary quasi-static states and of the estimation of successive structural disturbances during the 1200 s dynamics after a structural disturbance. The model is developed by detailed inspection of the time decomposition characteristics of automatic protection and control devices. Adequate speed of the numerical procedure is attained by a specific application of the inversion matrix lemma and the decoupled model constant coefficient matrices. The four-level time decomposition quasi-static method is intended for security and emergency analysis. (author).

  16. Power Flow Control through a Multi-Level H-Bridge-based Power Converter for Universal and Flexible Power Management in Future Electrical Grids

    Iov, Florin; Bifaretti, Steffano; Zanchetta, Pericle

    2008-01-01

    systems) on the AC side, and linked together at DC side by suitable DC isolation modules. Each port of the UNIFLEX-PM system employs a conversion structure based on a three-phase 7-level AC-DC cascaded converter. Effective and accurate power flow control is demonstrated through simulation in Matlab...... and Simulink environment on a simplified model based on a two-port structure and using a Stationery Reference Frame based control solution. Control of different Power flow profiles has been successfully tested in numerous network conditions such as voltage unbalance, frequency excursions and harmonic......The paper proposes a novel power conversion system for Universal and Flexible Power Management (UNIFLEX-PM) in Future Electricity Network. The structure is based on three AC-DC converters each one connected to a different grid, (representing the main grid and/or various distributed generation...

  17. Multiple external hazards compound level 3 PSA methods research of nuclear power plant

    Wang, Handing; Liang, Xiaoyu; Zhang, Xiaoming; Yang, Jianfeng; Liu, Weidong; Lei, Dina

    2017-01-01

    2011 Fukushima nuclear power plant severe accident was caused by both earthquake and tsunami, which results in large amount of radioactive nuclides release. That accident has caused the radioactive contamination on the surrounding environment. Although this accident probability is extremely small, once such an accident happens that is likely to release a lot of radioactive materials into the environment, and cause radiation contamination. Therefore, studying accidents consequences is important and essential to improve nuclear power plant design and management. Level 3 PSA methods of nuclear power plant can be used to analyze radiological consequences, and quantify risk to the public health effects around nuclear power plants. Based on multiple external hazards compound level 3 PSA methods studies of nuclear power plant, and the description of the multiple external hazards compound level 3 PSA technology roadmap and important technical elements, as well as taking a coastal nuclear power plant as the reference site, we analyzed the impact of off-site consequences of nuclear power plant severe accidents caused by multiple external hazards. At last we discussed the impact of off-site consequences probabilistic risk studies and its applications under multiple external hazards compound conditions, and explained feasibility and reasonableness of emergency plans implementation.

  18. Hybrid PV/diesel solar power system design using multi-level factor analysis optimization

    Drake, Joshua P.

    Solar power systems represent a large area of interest across a spectrum of organizations at a global level. It was determined that a clear understanding of current state of the art software and design methods, as well as optimization methods, could be used to improve the design methodology. Solar power design literature was researched for an in depth understanding of solar power system design methods and algorithms. Multiple software packages for the design and optimization of solar power systems were analyzed for a critical understanding of their design workflow. In addition, several methods of optimization were studied, including brute force, Pareto analysis, Monte Carlo, linear and nonlinear programming, and multi-way factor analysis. Factor analysis was selected as the most efficient optimization method for engineering design as it applied to solar power system design. The solar power design algorithms, software work flow analysis, and factor analysis optimization were combined to develop a solar power system design optimization software package called FireDrake. This software was used for the design of multiple solar power systems in conjunction with an energy audit case study performed in seven Tibetan refugee camps located in Mainpat, India. A report of solar system designs for the camps, as well as a proposed schedule for future installations was generated. It was determined that there were several improvements that could be made to the state of the art in modern solar power system design, though the complexity of current applications is significant.

  19. A DC-DC Converter Efficiency Model for System Level Analysis in Ultra Low Power Applications

    Benton H. Calhoun

    2013-06-01

    Full Text Available This paper presents a model of inductor based DC-DC converters that can be used to study the impact of power management techniques such as dynamic voltage and frequency scaling (DVFS. System level power models of low power systems on chip (SoCs and power management strategies cannot be correctly established without accounting for the associated overhead related to the DC-DC converters that provide regulated power to the system. The proposed model accurately predicts the efficiency of inductor based DC-DC converters with varying topologies and control schemes across a range of output voltage and current loads. It also accounts for the energy and timing overhead associated with the change in the operating condition of the regulator. Since modern SoCs employ power management techniques that vary the voltage and current loads seen by the converter, accurate modeling of the impact on the converter efficiency becomes critical. We use this model to compute the overall cost of two power distribution strategies for a SoC with multiple voltage islands. The proposed model helps us to obtain the energy benefits of a power management technique and can also be used as a basis for comparison between power management techniques or as a tool for design space exploration early in a SoC design cycle.

  20. Nonlinear Power-Level Control of the MHTGR Only with the Feedback Loop of Helium Temperature

    Zhe Dong

    2013-02-01

    Full Text Available Power-level control is a crucial technique for the safe, stable and efficient operation of modular high temperature gas-cooled nuclear reactors (MHTGRs, which have strong inherent safety features and high outlet temperatures. The current power-level controllers of the MHTGRs need measurements of both the nuclear power and the helium temperature, which cannot provide satisfactory control performance and can even induce large oscillations when the neutron sensors are in error. In order to improve the fault tolerance of the control system, it is important to develop a power-level control strategy that only requires the helium temperature. The basis for developing this kind of control law is to give a state-observer of the MHTGR a relationship that only needs the measurement of helium temperature. With this in mind, a novel nonlinear state observer which only needs the measurement of helium temperature is proposed. This observer is globally convergent if there is no disturbance, and has the L2 disturbance attenuation performance if the disturbance is nonzero. The separation principle of this observer is also proven, which denotes that this observer can recover the performance of both globally asymptotic stabilizers and L2 disturbance attenuators. Then, a new dynamic output feedback power-level control strategy is established, which is composed of this observer and the well-built static state-feedback power-level control based upon iterative dissipation assignment (IDA-PLC. Finally, numerical simulation results show the high performance and feasibility of this newly-built dynamic output feedback power-level controller.

  1. Modeling of interior noise levels in large combustion turbine power stations

    Hedeen, R.A. [GE Global Research, Niskayuna, NY (United States); Loud, R.L. [GE Energy, Schenectady, NY (United States)

    2007-07-01

    A study was conducted to predict noise emissions from power generating stations. In particular, the SoundPLAN4 ray-tracing program originally designed for exterior environmental noise propagation analysis, was used to predict the sound levels coming from inside combustion turbines and combined-cycle power plants. Although exterior sound levels are of interest due to their propagation into nearby communities, interior sound levels are important because of their influence on occupational noise exposure. Most regulations are concerned with an 85 dBA, 8 hour exposure. Therefore, plant designers, operators, and owners must be able to predict and control the areas in their plants where these regulations must be considered. In this study, the Raynoise 5 program was also used to analyze sound propagation. The ray-trace model considered the known sound power levels of the major pieces of equipment and was able to predict the sound distribution through the turbine hall with acceptable accuracy. The models used in this study were suitable for both compliance evaluation and noise target optimization of the individual power train components. It was concluded that the location and arrangement of the power train, off-base skids, and stand-alone equipment can be altered to control the sound level in desired areas of the plant. 7 refs., 4 figs.

  2. US power plant sites at risk of future sea-level rise

    Bierkandt, R.; Auffhammer, M.; Levermann, A.

    2015-12-01

    Unmitigated greenhouse gas emissions may increase global mean sea-level by about 1 meter during this century. Such elevation of the mean sea-level enhances the risk of flooding of coastal areas. We compute the power capacity that is currently out-of-reach of a 100-year coastal flooding but will be exposed to such a flood by the end of the century for different US states, if no adaptation measures are taken. The additional exposed capacity varies strongly among states. For Delaware it is 80% of the mean generated power load. For New York this number is 63% and for Florida 43%. The capacity that needs additional protection compared to today increases by more than 250% for Texas, 90% for Florida and 70% for New York. Current development in power plant building points towards a reduced future exposure to sea-level rise: proposed and planned power plants are less exposed than those which are currently operating. However, power plants that have been retired or canceled were less exposed than those operating at present. If sea-level rise is properly accounted for in future planning, an adaptation to sea-level rise may be costly but possible.

  3. Disentangling Bargaining Power from Individual and Household Level to Institutions: Evidence on Women’s Position in Ethiopia

    I.P. van Staveren (Irene); R. Mabsout (Ramzi)

    2010-01-01

    textabstractSUMMARY Women's bargaining power is generally analyzed only with individual level and household level variables. We add a third level, namely institutional bargaining power. We define this as bargaining power which one party freely derives from unequal social norms. In the bargaining lit

  4. Design and implementation of a DSP with multi-level low power strategies for cochlear implants

    Mai Songping; Zhang Chun; Chao Jun; Wang Zhihua

    2009-01-01

    This paper presents the design and implementation of a low power digital signal processor (THUCIDSP-1) targeting at application for cochlear implants. Multi-level low power strategies including algorithm optimization, operand isolation, clock gating and memory partitioning are adopted in the processor design to reduce the power consumption. Experimental results show that the complexity of the Continuous Interleaved Sampling (CIS) algorithm is reduced by more than 80% and the power dissipation of the hardware alone is reduced by about 25% with the low power methods. The THUCIDSP-1 prototype, fabricated in 0.18-μm standard CMOS process, consumes only 1.91 mW when executing the CIS algorithm at 3 MHz.

  5. Level-one modules library for DSNP: Dynamic Simulator for Nuclear Power-plants

    Saphier, D.

    1978-09-01

    The Dynamic Simulator for Nuclear Power-plants (DSNP) is a system of programs and data sets by which a nuclear power plant or part thereof can be simulated at different levels of sophistication. The acronym DSNP is used interchangeably for the DSNP language, for the DSNP precompiler, for the DSNP libraries, and for the DSNP document generator. The DSNP language is a set of simple block oriented statements, which together with the appropriate data, comprise a simulation of a nuclear power plant. The majority of the DSNP statements will result in the inclusion of a simulated physical module into the program. FORTRAN statements can be inserted with no restrictions among DSNP statements.

  6. Design and operation of 140 GHz gyrotron oscillators for power levels up to 1 MW CW

    Jory, H.; Bier, R.; Craig, L.J.; Felch, K.; Ives, L.; Lopez, N.; Spang, S.

    1986-12-01

    Varian has designed and tested 140 GHz gyrotron oscillators that have generated output powers of 100 kW CW and 200 kW for 1 ms pulses. Upcoming tubes will be designed to operate at power levels of 200 kW CW and ultimately up to 1 MW CW. The important design considerations which are addressed in the higher power tubes include the design of the electron gun, interaction circuit, and output window. These issues will be discussed and the results of the earlier 140 GHz gyrotron work at Varian will be summarized.

  7. Battery Recharging Issue for a Two-Power-Level Flywheel System

    Janaína Gonçalves de Oliveira

    2010-01-01

    Full Text Available A novel battery recharging system for an all-electric driveline comprising a flywheel with a permanent magnet double wound synchronous machine (motor/generator is presented. The double winding enables two voltage levels and two different power levels. This topology supersedes other all-electric drivelines. The battery operates in a low-power regime supplying the average power whereas the flywheel delivers and absorbs power peaks, which are up to a higher order of magnitude. The topology presents new challenges for the power conversion system, which is the focus of this investigation. The main challenge is the control of the power flow to the battery when the vehicle is parked despite the decay of the flywheel machine voltage; which is dependent on its charge state, that is, rotational speed. The design and simulation of an unidirectional DC/DC buck/boost converter for a variable rotational speed flywheel is presented. Conventional power electronic converters are used in a new application, which can maintain a constant current or voltage on the battery side. Successful PI current control has been implemented and simulated, together with the complete closed loop system.

  8. Architecture-level performance/power tradeoff in network processor design

    CHEN Hong-song; JI Zhen-zhou; HU Ming-zeng

    2007-01-01

    Network processors are used in the core node of network to flexibly process packet streams. With the increase of performance, the power of network processor increases fast, and power and cooling become a bottleneck. Architecture-level power conscious design must go beyond low-level circuit design. Architectural power and performance tradeoff should be considered at the same time. Simulation is an efficient method to design modern network processor before making chip. In order to achieve the tradeoff between performance and power,the processor simulator is used to design the architecture of network processor. Using Netbench, Commubench benchmark and processor simulator-SimpleScalar, the performance and power of network processor are quantitatively evaluated. New performance tradeoff evaluation metric is proposed to analyze the architecture of network processor. Based on the high performance Intel IXP 2800 Network processor configuration, optimized instruction fetch width and speed 、instruction issue width, instruction window size are analyzed and selected. Simulation results show that the tradeoff design method makes the usage of network processor more effectively. The optimal key parameters of network processor are important in architecture-level design. It is meaningful for the next generation network processor design.

  9. Design for reliability in power electronics in renewable energy systems – status and future

    Wang, Huai; Blaabjerg, Frede; Ma, Ke

    2013-01-01

    Advances in power electronics enable efficient and flexible interconnection of renewable sources, loads and electric grids. While targets concerning efficiency of power converters are within reach, recent research endeavors to predict and improve their reliability to ensure high availability, low......, the lifetime prediction of reliability-critical components IGBT modules is discussed in a 2.3 MW wind power converter. Finally, the challenges and opportunities to achieve more reliable power electronic converters are discussed....... maintenance costs, and herefore, low Levelized-Cost-of-Energy (LCOE) of renewable energy systems. This paper presents the prior-art Design for Reliability (DFR) process for power converters and addresses the paradigm shift to Physics-of-Failure (PoF) approach and mission profile based analysis. Moreover...

  10. Dynamic Output Feedback Power-Level Control for the MHTGR Based On Iterative Damping Assignment

    Zhe Dong

    2012-06-01

    Full Text Available Because of its strong inherent safety features and high outlet temperature, the modular high temperature gas-cooled nuclear reactor (MHTGR is already seen as the central part of the next generation of nuclear plants. Such power plants are being considered for industrial applications with a wide range of power levels, and thus power-level control is an important technique for their efficient and stable operation. Stimulated by the high regulation performance provided by nonlinear controllers, a novel dynamic output-feedback nonlinear power-level regulator is developed in this paper based on the technique of iterative damping assignment (IDA. This control strategy can provide the L2 disturbance attenuation performance under modeling uncertainty or exterior disturbance, and can also guarantee the globally asymptotic closed-loop stability without uncertainty and disturbance. This newly built control strategy is then applied to the power-level regulation of the HTR-PM plant, and numerical simulation results show both the feasibility and high performance of this newly-built control strategy. Furthermore, the relationship between the values of the parameters and the performance of this controller is not only illustrated numerically but also analyzed theoretically.

  11. Method for Calculating CO2 Emissions from the Power Sector at the Provincial Level in China

    MA Cui-Mei; GE Quan-Sheng

    2014-01-01

    Based on the detailed origins of each province’s electricity consumption, a new method for calculating CO2 emissions from the power sector at the provincial level in China is proposed. With this so-called consumer responsibility method, the emissions embodied in imported electricity are calculated with source-specific emission factors. Using the new method, we estimate CO2 emissions in 2005 and 2010. Compared with those derived from the producer responsibility method, the power exporters’ emissions decreased sharply. The emissions from the power sector in Inner Mongolia, the largest power exporter of China, decreased by 109 Mt in 2010. The value is equivalent to those from Shaanxi’s power production and Canada’s power and heat production. In contrast, the importers’ emissions increased substantially. The emissions from the power sector in Hebei, the largest power importer of China, increased by 74 Mt. Emissions of Beijing, increased by 60 Mt (320%), in 2010. Thus, we suggest that the Chinese government should take the emissions, as calculated from the consumption perspective, into account when formulating and assessing local CO2 emission reduction targets.

  12. A NOVEL CAPACITY ANALYZING METHOD FOR MULTIMEDIA CDMA SYSTEMS BASED ON POWER LEVEL ALLOCATION

    Pan Su; Tung Sang Ng; Feng Guangzeng

    2006-01-01

    A novel method is proposed to analyze the capacity of future Code Division Multiple Access (CDMA) systems carrying multimedia services. The power level allocation is firstly investigated to meet each call's Bit Error Rate (BER) requirement, then the system capacity is defined from the conditions for the existence of the physical meaning of these power levels. Simulation results have shown that the capacity analyzing methods can be well used in the performance evaluation of the system accommodating heterogeneous services and the spectral efficiency of this scheme is higher than the existing ones.

  13. Energy Use and Power Levels in New Monitors and Personal Computers

    Roberson, Judy A.; Homan, Gregory K.; Mahajan, Akshay; Nordman, Bruce; Webber, Carrie A.; Brown, Richard E.; McWhinney, Marla; Koomey, Jonathan G.

    2002-07-23

    Our research was conducted in support of the EPA ENERGY STAR Office Equipment program, whose goal is to reduce the amount of electricity consumed by office equipment in the U.S. The most energy-efficient models in each office equipment category are eligible for the ENERGY STAR label, which consumers can use to identify and select efficient products. As the efficiency of each category improves over time, the ENERGY STAR criteria need to be revised accordingly. The purpose of this study was to provide reliable data on the energy consumption of the newest personal computers and monitors that the EPA can use to evaluate revisions to current ENERGY STAR criteria as well as to improve the accuracy of ENERGY STAR program savings estimates. We report the results of measuring the power consumption and power management capabilities of a sample of new monitors and computers. These results will be used to improve estimates of program energy savings and carbon emission reductions, and to inform rev isions of the ENERGY STAR criteria for these products. Our sample consists of 35 monitors and 26 computers manufactured between July 2000 and October 2001; it includes cathode ray tube (CRT) and liquid crystal display (LCD) monitors, Macintosh and Intel-architecture computers, desktop and laptop computers, and integrated computer systems, in which power consumption of the computer and monitor cannot be measured separately. For each machine we measured power consumption when off, on, and in each low-power level. We identify trends in and opportunities to reduce power consumption in new personal computers and monitors. Our results include a trend among monitor manufacturers to provide a single very low low-power level, well below the current ENERGY STAR criteria for sleep power consumption. These very low sleep power results mean that energy consumed when monitors are off or in active use has become more important in terms of contribution to the overall unit energy consumption (UEC

  14. Improvement of High-Power Three-Level Explosion-Proof Inverters Using Soft Switching Control Based on Optimized Power-Loss Algorithm

    Shi-Zhou Xu

    2015-01-01

    Full Text Available The high-power three-level explosion-proof inverters demand high thermal stability of power devices, and a set of theories and methods is needed to achieve an accurate power-loss calculation of power devices, to establish heat dissipation model, and ultimately to reduce the power loss to improve thermal stability of system. In this paper, the principle of neutral point clamped three-level (NPC3L inverter is elaborated firstly, and a fourth-order RC equivalent circuit of IGBT is derived, on which basis the power-loss model of IGBT and the optimized maternal power-loss thermal model, using an optimized power-loss algorithm, are established. Secondly, in accordance with the optimized maternal power-loss thermal model, the generic formulas of power-loss calculation are deduced to calculate the power-loss modification values of NPC3L and soft switching three-level (S3L inverters, which will be the thermal sources during thermal analysis for maternal power-loss thermal models. Finally, the experiment conducted on the 2.1 MW experimental platform shows that S3L inverter has the same excellent output characteristics with NPC3L inverter, reduces the power loss significantly by 213 W in each half-bridge, and decreases the temperature by 10°C, coinciding with the theoretical calculation, which verifies the accuracy of optimized power-loss algorithm and the effectiveness of the improvement.

  15. A novel synthetic test system for thyristor level in the converter valve of HVDC power transmission

    Liu Longchen

    2016-01-01

    Full Text Available The converter valve is the core equipment in the HVDC power transmission system, a+-nd its performance has a direct effect on the reliability, stability and efficiency of the whole power system. As the basic unit of HVDC converter valve, the thyristor level needs to be test routinely in order to grasp the state of the converter valve equipment. Therefore, it is urgent to develop a novel synthetic test system for the thyristor level with thyristor control unit (TCU. However, currently there is no specific test scheme for the thyristor level of HVDC converter valve. In this paper, the synthetic test principle, content and methods for the thyristor level with TCU are presented based on the analysis of the thyristor reverse recovery characteristic and the IEC technology standard. And a transient high-voltage pulse is applied to the thyristor level during its reverse recovery period in order to test the characteristics of thyristor level. Then, the synthetic test system for the thyristor level is applied to the converter valve test of ±800 kV HVDC power transmission project, and the practical test result verifies the reasonability and validity of the proposed synthetic test system.

  16. Thermal analysis of multi-MW two-level wind power converter

    Zhou, Dao; Blaabjerg, Frede; Mogens, Lau;

    2012-01-01

    In this paper, the multi-MW wind turbine of partial-scale and full-scale two-level power converter with DFIG and direct-drive PMSG are designed and compared in terms of their thermal performance. Simulations of different configurations regarding loss distribution and junction temperature in the p......In this paper, the multi-MW wind turbine of partial-scale and full-scale two-level power converter with DFIG and direct-drive PMSG are designed and compared in terms of their thermal performance. Simulations of different configurations regarding loss distribution and junction temperature...... in the power device in the whole range of wind speed are presented and analyzed. It is concluded that in both partial-scale and full-scale power converter the most thermal stressed power device in the generator-side converter will have higher mean junction temperature and larger junction temperature...... fluctuation compared to grid-side converter at the rated wind speed. Moreover, the thermal performance of the generator-side converter in the partial-scale power converter becomes crucial around the synchronous operating point and should be considered carefully....

  17. Biographical learning in top-level coaching - personal styles and the power of practical sense

    Christensen, Mette Krogh

    : Biographical learning in top-level coaching - personal styles and the power of practical sense. There is a growing body of studies in sports coaching cultures, comprising research focusing on the individual learning processes and life histories of top-level coaches. Even if top-level sport has become...... increasingly professionalized, the role of the top-level coach and the developmental pathways of the coaches differ widely in both areas of experience and amount of experience. In this paper I draw on theories on biographical learning, idiosyncratic learning and development of coaching expertise. This paper...

  18. Influence of the power level of an ultra-sonic system on dental cavity preparation.

    Josgrilberg, Erika Botelho; Guimarães, Murilo de Sousa; Pansani, Cyneu Aguiar; Cordeiro, Rita de Cássia Loiola

    2007-01-01

    The aim of this study was to evaluate the shape of dental cavities made with the CVDentus system using different ultrasound power levels. One standard cavity was made on the buccal aspect of 15 bovine incisors with a CVDentus cylindrical bur (82142). The sample was divided into three groups: G1-ultrasound with power II; G2-ultrasound with power III; and G3-ultrasound with power IV. A standardizing device was used to obtain standardized preparations and ultrasound was applied during one minute in each dental preparation. The cavities were sectioned in the middle, allowing observation of the cavity's profile with a magnifying glass, and width and depth measurement using the Leica Qwin program. The Kruskal-Wallis (p<0.05) and Dunn statistical analyses demonstrated differences between the dental cavity shapes when powers III and IV were used. However, the cavities that were made with power III presented dimensions similar to those of the bur used for preparation. We concluded that the power recommended by the manufacturer (III) is the most adequate for use with the CVDentus system.

  19. A Polymer Optical Fiber Fuel Level Sensor: Application to Paramotoring and Powered Paragliding

    David Sánchez Montero; Carmen Vázquez; Pedro Contreras Lallana

    2012-01-01

    A low-cost intensity-based polymer optical fiber (POF) sensor for fuel level measurements in paramotoring and powered paragliding is presented, exploiting the advantages of the optical fiber sensing technology. Experimental results demonstrate that the best option can be performed by stripping the fiber at the desired discrete points to measure the fuel level as well as with a gauge-shape fiber bending. The prototype has a good linearity, better than 4% full scale (F.S.), and sensitivity arou...

  20. The Evolution of Power System Planning with High Levels of Variable Renewable Generation

    Katz, Jessica [National Renewable Energy Lab. (NREL), Golden, CO (United States); Milligan, Michael [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2016-09-01

    Greening the Grid provides technical assistance to energy system planners, regulators, and grid operators to overcome challenges associated with integrating variable renewable energy into the grid. This document, part of the Greening the Grid introduces the evolution of power system planning with high levels of variable renewable generation.

  1. Empirical LTE Smartphone Power Model with DRX Operation for System Level Simulations

    Lauridsen, Mads; Noël, Laurent; Mogensen, Preben

    2013-01-01

    An LTE smartphone power model is presented to enable academia and industry to evaluate users’ battery life on system level. The model is based on empirical measurements on a smartphone using a second generation LTE chipset, and the model includes functions of receive and transmit data rates...

  2. A stationary reference frame current control for a multi-level H-bridge power converter for universal and flexible power management in future electricity network

    Ciobotaru, Mihai; Iov, Florin; Zanchetta, Pericle;

    2008-01-01

    for a multi-level cascaded H-bridges power converter used for grid applications. Harmonic content in the Point of Common Coupling, system response for bidirectional power flow, voltage and frequency excursions as well as voltage unbalances and asymmetries and low voltage ride-though capabilities are studied.......More "green" power provided by Distributed Generation will enter into the European electricity network in the near future. In order to control the power flow and to ensure proper and secure operation of this future grid, with an increased level of the renewable power, new power electronic...... converters for grid connection of renewable sources will be needed. These power converters must be able to provide intelligent power management as well as ancillary services. This paper assesses a control method based on the stationary reference frame with Proportional-Resonant current controllers...

  3. Survey of ambient electromagnetic and radio-frequency interference levels in nuclear power plants

    Kercel, S.W.; Moore, M.R.; Blakeman, E.D.; Ewing, P.D.; Wood, R.T.

    1996-11-01

    This document reports the results of a survey of ambient electromagnetic conditions in representative nuclear power plants. The U.S. Nuclear Regulatory Commission (NRC) Office of Nuclear Regulatory Research engaged the Oak Ridge National Laboratory (ORNL) to perform these measurements to characterize the electromagnetic interference (EMI) and radio-frequency interference (RFI) levels that can be expected in nuclear power plant environments. This survey is the first of its kind, being based on long-term unattended observations. The data presented in this report were measured at eight different nuclear units and required 14 months to collect. A representative sampling of power plant conditions (reactor type, operating mode, site location) monitored over extended observation periods (up to 5 weeks) were selected to more completely determine the characteristic electromagnetic environment for nuclear power plants. Radiated electric fields were measured over the frequency range of 5 MHz to 8 GHz. Radiated magnetic fields and conducted EMI events were measured over the frequency range of 305 Hz to 5 MHz. Highest strength observations of the electromagnetic ambient environment across all measurement conditions at each site provide frequency-dependent profiles for EMI/RFI levels in nuclear power plants.

  4. Multi-spacecraft measurement of anisotropic power levels and scaling in solar wind turbulence

    K. T. Osman

    2009-08-01

    Full Text Available Measurements by the four Cluster spacecraft in the solar wind are used to determine quantitatively the field-aligned anisotropy of magnetohydrodynamic inertial range turbulence power levels and spectral indexes. We find, using time-lagged second order structure functions, that the spectral index is near 2 around the field-parallel direction, which is consistent with a "critical balance" turbulent cascade. Solar wind fluctuations are found to be anisotropic with power mainly in wavevectors perpendicular to the mean field, where the spectral index is around 5/3.

  5. Photovoltaic Shading Testbed for Module-Level Power Electronics: 2016 Performance Data Update

    Deline, Chris [National Renewable Energy Lab. (NREL), Golden, CO (United States); Meydbray, Jenya [PV Evolution Labs (PVEL), Davis, CA (United States); Donovan, Matt [PV Evolution Labs (PVEL), Davis, CA (United States)

    2016-09-01

    The 2012 NREL report 'Photovoltaic Shading Testbed for Module-Level Power Electronics' provides a standard methodology for estimating the performance benefit of distributed power electronics under partial shading conditions. Since the release of the report, experiments have been conducted for a number of products and for different system configurations. Drawing from these experiences, updates to the test and analysis methods are recommended. Proposed changes in data processing have the benefit of reducing the sensitivity to measurement errors and weather variability, as well as bringing the updated performance score in line with measured and simulated values of the shade recovery benefit of distributed PV power electronics. Also, due to the emergence of new technologies including sub-module embedded power electronics, the shading method has been extended to include power electronics that operate at a finer granularity than the module level. An update to the method is proposed to account for these emerging technologies that respond to shading differently than module-level devices. The partial shading test remains a repeatable test procedure that attempts to simulate shading situations as would be experienced by typical residential or commercial rooftop photovoltaic (PV) systems. Performance data for multiple products tested using this method are discussed, based on equipment from Enphase, Solar Edge, Maxim Integrated and SMA. In general, the annual recovery of shading losses from the module-level electronics evaluated is 25-35%, with the major difference between different trials being related to the number of parallel strings in the test installation rather than differences between the equipment tested. Appendix D data has been added in this update.

  6. Low-power multi-chip module and board-level links for data transfer

    Carson, R.F.; Hardin, T.L.; Warren, M.E.; Lear, K.L.; Lovejoy, M.L.; Seigal, P.K.; Craft, D.C. [Sandia National Labs., Albuquerque, NM (United States); Enquist, P.J. [Research Triangle Inst., Research Triangle Park, NC (United States)

    1997-03-01

    Advanced device technologies such as Vertical Cavity Surface-Emitting Lasers (VCSELs) and diffractive micro lenses can be obtained with novel packaging techniques to allow low-power interconnection of parallel optical signals. These interconnections can be realized directly on circuit boards, in a multi-chip module format, or in packages that emulate electrical connectors. For applications such as stacking of Multi-Chip Module (MCM) layers, the links may be realized in bi-directional form using integrated diffractive microlenses. In the stacked MCM design, consumed electrical power is minimized by use of a relatively high laser output from high efficiency VCSELs, and a receiver design that is optimized for low power, at the expense of dynamic range. Within certain constraints, the design may be extended to other forms such as board-level interconnects.

  7. Power optimization of digital baseband WCDMA receiver components on algorithmic and architectural level

    M. Schämann

    2008-05-01

    Full Text Available High data rates combined with high mobility represent a challenge for the design of cellular devices. Advanced algorithms are required which result in higher complexity, more chip area and increased power consumption. However, this contrasts to the limited power supply of mobile devices.

    This presentation discusses the application of an HSDPA receiver which has been optimized regarding power consumption with the focus on the algorithmic and architectural level. On algorithmic level the Rake combiner, Prefilter-Rake equalizer and MMSE equalizer are compared regarding their BER performance. Both equalizer approaches provide a significant increase of performance for high data rates compared to the Rake combiner which is commonly used for lower data rates. For both equalizer approaches several adaptive algorithms are available which differ in complexity and convergence properties. To identify the algorithm which achieves the required performance with the lowest power consumption the algorithms have been investigated using SystemC models regarding their performance and arithmetic complexity. Additionally, for the Prefilter Rake equalizer the power estimations of a modified Griffith (LMS and a Levinson (RLS algorithm have been compared with the tool ORINOCO supplied by ChipVision. The accuracy of this tool has been verified with a scalable architecture of the UMTS channel estimation described both in SystemC and VHDL targeting a 130 nm CMOS standard cell library.

    An architecture combining all three approaches combined with an adaptive control unit is presented. The control unit monitors the current condition of the propagation channel and adjusts parameters for the receiver like filter size and oversampling ratio to minimize the power consumption while maintaining the required performance. The optimization strategies result in a reduction of the number of arithmetic operations up to 70% for single components which leads to an

  8. Explosive power of lower limbs in rhythmic gymnastics athletes in different competitive levels

    Amanda Batista SANTOS

    2016-03-01

    Full Text Available Abstract The explosive power in Rhythmic Gymnastics shows itself in the great majority of movements and elements performed by the gymnasts, particularly in the jumps, which are essential corporal movements in this sport. The training directed to the development of jumping capacity presents a large quantity of exercises which aim to improve muscular power in the lower limbs and therefore the impulsion capacity. The vertical impulsion is an important measure used to calculate the explosive power of the lower limbs and is directly connected to the success that the gymnast will be able to achieve. Therefore, the aim of this study is to evaluate the height of two jumps in the RG (stag jump and Cossack jump in contact mat Ergojump, which calculates the jump height in connection with the flight timing, executed by national level junior gymnasts and to compare them to the results of the Junior National Team - in total 30 junior gymnasts with 13.73 ± 0.17 years old. Furthermore, to compare the levels of explosive power of preferred lower limb (PLL and non-preferred lower limb (NPLL of all gymnasts in the study, in order to verify eventual functional asymmetries. For the statistical analysis we used Parametric Tests (t Test and Nonparametric (Mann-Whitney Test and Wilcoxon Test. The gymnasts of the National Team achieved superior marks in 33.3% of the tests and 83.3% of the gymnasts of our sample did not present explosive power asymmetries. We conclude that the gymnasts of the National Team did not show the expected superiority in the tests, and the most of gymnasts presented a harmonious development of explosive power for both lower limbs, since they did not show functional asymmetries.

  9. Modelling and measurement of the absolute level of power radiated by antenna integrated THz UTC photodiodes.

    Natrella, Michele; Liu, Chin-Pang; Graham, Chris; van Dijk, Frederic; Liu, Huiyun; Renaud, Cyril C; Seeds, Alwyn J

    2016-05-30

    We determine the output impedance of uni-travelling carrier (UTC) photodiodes at frequencies up to 400 GHz by performing, for the first time, 3D full-wave modelling of detailed UTC photodiode structures. In addition, we demonstrate the importance of the UTC impedance evaluation, by using it in the prediction of the absolute power radiated by an antenna integrated UTC, over a broad frequency range and confirming the predictions by experimental measurements up to 185 GHz. This is done by means of 3D full-wave modelling and is only possible since the source (UTC) to antenna impedance match is properly taken into account. We also show that, when the UTC-to-antenna coupling efficiency is modelled using the classical junction-capacitance/series-resistance concept, calculated and measured levels of absolute radiated power are in substantial disagreement, and the maximum radiated power is overestimated by a factor of almost 7 dB. The ability to calculate the absolute emitted power correctly enables the radiated power to be maximised through optimisation of the UTC-to-antenna impedance match.

  10. Effect of Low-Level Laser Stimulation on EEG Power in Normal Subjects with Closed Eyes

    Jih-Huah Wu

    2013-01-01

    Full Text Available In a previous study, we found that the low-level laser (LLL stimulation at the palm with a frequency of 10 Hz was able to induce significant brain activation in normal subjects with opened eyes. However, the electroencephalography (EEG changes to LLL stimulation in subjects with closed eyes have not been studied. In the present study, the laser array stimulator was applied to deliver insensible laser stimulations to the palm of the tested subjects with closed eyes (the laser group. The EEG activities before, during, and after the laser stimulation were collected. The EEG amplitude powers of each EEG frequency band at 19 locations were calculated. These power data were then analyzed by SPSS software using repeated-measure ANOVAs and appropriate posthoc tests. We found a pronounced decrease in the EEG power in alpha-bandwidth during laser simulation and then less decrease in the EEG power in delta-bandwidth in normal subjects with laser stimulation. The EEG power in beta-bandwidth in the right occipital area also decreased significantly in the laser group. We suggest that LLL stimulation might be conducive to falling into sleep in patients with sleep problems.

  11. Habit, custom, and power: a multi-level theory of population health.

    Zimmerman, Frederick J

    2013-03-01

    In multi-level theory, individual behavior flows from cognitive habits, either directly through social referencing, rules of thumb, or automatic behaviors; or indirectly through the shaping of rationality itself by framing or heuristics. Although behavior does not arise from individually rational optimization, it generally appears to be rational, because the cognitive habits that guide behavior evolve toward optimality. However, power imbalances shaped by particular social, political, and economic structures can distort this evolution, leading to individual behavior that fails to maximize individual or social well-being. Replacing the dominant rational-choice paradigm with a multi-level theoretical paradigm involving habit, custom, and power will enable public health to engage in rigorous new areas of research.

  12. A Transformer-less Partial Power Boost Converter for PV Applications Using a Three-Level Switching Cell

    Agamy, Mohammed; Harfman-Todorovic, Maja; Elasser, Ahmed; Essakiappan, Somasundaram

    2013-03-01

    Photovoltaic architectures with distributed power electronics provide many advantages in terms of energy yield as well as system level optimization. As the power level of the solar farm increases it becomes more beneficial to increase the dc collection network voltage, which requires the use of power devices with higher voltage ratings, and thus making the design of efficient, low cost, distributed power converters more challenging. In this paper a simple partial power converter topology is proposed. The topology is implemented using a three-level switching cell, which allows the use of semiconductor devices with lower voltage rating; thus improving design and performance and reducing converter cost. This makes the converters suitable for use for medium to high power applications where dc-link voltages of 600V~1kV may be needed without the need for high voltage devices. Converter operation and experimental results are presented for two partial power circuit variants using three-level switching cells.

  13. Nonlinear Adaptive Dynamic Output-Feedback Power-Level Control of Nuclear Heating Reactors

    Zhe Dong

    2013-01-01

    Full Text Available Due to the high safety performance of small nuclear reactors, there is a promising future for small reactors. Nuclear heating reactor (NHR is a small reactor that has many advanced safety features such as the integrated arrangement, natural circulation at any power levels, self-pressurization, hydraulic control rod driving, and passive residual heating removing and can be applied to the fields of district heating, seawater desalination, and electricity production. Since the NHR dynamics has strong nonlinearity and uncertainty, it is meaningful to develop the nonlinear adaptive power-level control technique. From the idea of physically based control design method, a novel nonlinear adaptive power-level control is given for the NHR in this paper. It is theoretically proved that this newly built controller does not only provide globally asymptotic closed-loop stability but is also adaptive to the system uncertainty. Numerical simulation results show the feasibility of this controller and the relationship between the performance and controller parameters.

  14. A Polymer Optical Fiber Fuel Level Sensor: Application to Paramotoring and Powered Paragliding

    David Sánchez Montero

    2012-05-01

    Full Text Available A low-cost intensity-based polymer optical fiber (POF sensor for fuel level measurements in paramotoring and powered paragliding is presented, exploiting the advantages of the optical fiber sensing technology. Experimental results demonstrate that the best option can be performed by stripping the fiber at the desired discrete points to measure the fuel level as well as with a gauge-shape fiber bending. The prototype has a good linearity, better than 4% full scale (F.S., and sensitivity around 0.5 V per bend are obtained. Hysteresis due to residual fluid at the sensing points is found to be less than 9% F.S.

  15. A polymer optical fiber fuel level sensor: application to paramotoring and powered paragliding.

    Sánchez Montero, David; Contreras Lallana, Pedro; Vázquez, Carmen

    2012-01-01

    A low-cost intensity-based polymer optical fiber (POF) sensor for fuel level measurements in paramotoring and powered paragliding is presented, exploiting the advantages of the optical fiber sensing technology. Experimental results demonstrate that the best option can be performed by stripping the fiber at the desired discrete points to measure the fuel level as well as with a gauge-shape fiber bending. The prototype has a good linearity, better than 4% full scale (F.S.), and sensitivity around 0.5 V per bend are obtained. Hysteresis due to residual fluid at the sensing points is found to be less than 9% F.S.

  16. ENERGY EFFICIENT FLOW AND LEVEL CONTROL IN A HYDRO POWER PLANT USING FUZZY LOGIC

    A. Selwin Mich Priyadharson

    2014-01-01

    Full Text Available The main objective and an innovative design of this work is to improve the energy efficiency by controlling the variables flow and level in a hydroelectric power plant using Programmable Logic Control (PLC-Human Machine Interface (HMI and fuzzy logic approach. This project will focus on design and development of flow and level controller for small scale hydro generating units by implementing gate control based on PLC-HMI and Fuzzy Logic Control (FLC. So far there is no other better performing control scheme, with uncomplicated approach, in order to match and satisfy the dynamic changes in load demand. In this project, FLC will be applied to flow and level control for small scale hydro generating units is proposed. A lab scale experimental setup is made-up as prototype model for flow and level control and simulation outputs were achieved, using PLC-HMI based fuzzy controller scheme. The hardware set up is designed with 5 stages in the tank 1 and 2 stages in the tank 2. Based on the outputs of the level sensors from tanks 1 and 2, the ladder logic will perform. B&R Industrial Automation PLC inbuilt with 24 digital inputs and provides 16 potential free outputs is used to perform control action. Finally, the performance of the proposed scheme is evaluated by simulation results by comparing with conventional controllers output using the data collected from the hydroelectric power plant. The merits of the proposed Fuzzy scheme over the conventional method are spotlighted.

  17. Reactive power control with CHP plants - A demonstration

    Nyeng, Preben; Østergaard, Jacob; Andersen, Claus A.;

    2010-01-01

    power rating of 7.3 MW on two synchronous generators. A closed-loop control is implemented, that remote controls the CHP plant to achieve a certain reactive power flow in a near-by substation. The solution communicates with the grid operator’s existing SCADA system to obtain measurements from...

  18. Analysis of individual- and school-level clustering of power frequency magnetic fields.

    Lin, I-Fan; Li, Chung-Yi; Wang, Jung-Der

    2008-10-01

    This study reports the continuous 8-h monitoring of data on extremely low-frequency magnetic fields (ELF-MF) relating to 14 children and 35 teachers in 11 elementary schools in Northern Taiwan. It was anticipated that the subjects in two of these campuses would have elevated exposure to ELF-MF as a result of their close proximity to high-voltage (161 kilo-Volt, kV) power lines. The results of our analysis reveal that in those schools with high-voltage power lines running through the campuses, the mean ELF-MF exposure level (0.38 +/- 0.51 micro-Tesla (microT), or 0.15, 0.25 and 0.44 microT at the respective 25th, 50th and 75th percentiles) was higher than the mean ELF-MF exposure level for campuses situated far away from such high-voltage power lines (0.14 +/- 0.27 microT, or 0.04, 0.06 and 0.10 microT at the respective 25th, 50th and 75th percentiles). The multi-level analytical technique, which takes individual measurements as the analytical unit, and which also takes into consideration the inter-correlation between measurements from the same individual and/or campus, was also applied to the analysis of the data. We conclude that individual-level and school-level clustering of the measurements, both of which were discernible in this study, should be taken into consideration in any future analysis of data obtained from the continuous monitoring of exposure to ELF-MF.

  19. Power Quality Improvement at Distribution Level for Grid Connected Renewable Energy Sources

    S. Syed Ahmed

    2014-09-01

    Full Text Available The non-linear load current harmonics may result in voltage harmonics and can create a serious PQ problem in the power system network. Active power filters (APF are extensively used to compensate the load current harmonics and load unbalance at distribution level. This results in an additional hardware cost. However, in this project it has incorporated the features of APF in the conventional inverter interfacing renewable with the grid, without any additional hardware cost. Here, the main idea is the maximum utilization of inverter rating which is most of the time underutilized due to intermittent nature of RES. The grid-interfacing inverter can effectively be utilized to perform the four important functions they are to transfer active power harvested from the renewable resources (wind, solar, etc., load reactive power demand support, current harmonics compensation at PCC and current unbalance and neutral current compensation in case of 3-phase 4-wire system. Moreover, with adequate control of grid-interfacing inverter, all the four objectives can be accomplished either individually or simultaneously. The PQ constraints at the PCC can therefore be strictly maintained within the utility standards without additional hardware cost. With such a control, the combination of grid-interfacing inverter and the 3-phase 4-wire linear/non-linear unbalanced load at point of common coupling appears as balanced linear load to the grid. This new control concept is demonstrated with extensive MATLAB/Simulink simulation studies

  20. A detector for monitoring the onset of cavitation during therapy-level measurements of ultrasonic power

    Hodnett, M; Zeqiri, B [National Physical Laboratory, Queens Road, Teddington, Middlesex, TW11 0LW (United Kingdom)

    2004-01-01

    Acoustic cavitation occurring in the water path between a transducer and the target of a radiation force balance can provide a significant source of error during measurements of ultrasonic power. These problems can be particularly acute at physiotherapy levels (>1 W), and low frequencies ({<=} 1 MHz). The cavitating bubbles can absorb and scatter incident ultrasound, leading to an underestimate in the measured power. For these reasons, International Specification standards demand the use of degassed water. This imposes requirements that may actually be difficult to meet, for example, in the case of hospitals. Also, initially degassed water will rapidly re-gas, increasing the likelihood of cavitation occurring. For these reasons, NPL has developed a device that monitors acoustic emissions generated by bubble activity, for detecting the onset of cavitation during power measurements. A commercially available needle hydrophone is used to detect these emissions. The acoustic signals are then monitored using a Cavitation Detector (CD) unit, comprising an analogue electrical filter that may be tuned to detect frequency components generated by cavitating bubbles, and which provides an indication of when the measured level exceeds a pre-defined threshold. This paper describes studies to establish a suitable detection scheme, the principles of operation of the CD unit, and the performance tests carried out with a range of propagation media.

  1. Assessment of two-level heat pump installations’ power efficiency for heat supply systems

    Аlla Е. Denysova

    2015-06-01

    Full Text Available The problem of energy saving becomes one of the most important in power engineering. It is caused by exhaustion of world reserves in hydrocarbon fuel, such as gas, oil and coal representing sources of traditional heat supply. Conventional sources has essential shortcomings: low power, ecological and economic efficiencies, that can be eliminated by using alternative methods of power supply, like the considered one: low-temperature natural heat of ground waters of on the basis of heat pump installations application. The heat supply system considered provides an effective use of two-level heat pump installation operating as heat source the Odessa city ground waters during the lowest ambient temperature period. Proposed is a calculation method of heat pump installations on the basis of geothermal heat supply. Calculated are the values of electric energy consumption N by the compressors’ drive, and the heat supply system transformation coefficient µ for a source of geothermal heat from ground waters of Odessa city allowing to estimate efficiency of two-level heat pump installations.

  2. Islanding the power grid on the transmission level: less connections for more security

    Mureddu, Mario; Caldarelli, Guido; Damiano, Alfonso; Scala, Antonio; Meyer-Ortmanns, Hildegard

    2016-10-01

    Islanding is known as a management procedure of the power system that is implemented at the distribution level to preserve sensible loads from outages and to guarantee the continuity in electricity supply, when a high amount of distributed generation occurs. In this paper we study islanding on the level of the transmission grid and shall show that it is a suitable measure to enhance energy security and grid resilience. We consider the German and Italian transmission grids. We remove links either randomly to mimic random failure events, or according to a topological characteristic, their so-called betweenness centrality, to mimic an intentional attack and test whether the resulting fragments are self-sustainable. We test this option via the tool of optimized DC power flow equations. When transmission lines are removed according to their betweenness centrality, the resulting islands have a higher chance of being dynamically self-sustainable than for a random removal. Less connections may even increase the grid’s stability. These facts should be taken into account in the design of future power grids.

  3. Islanding the power grid on the transmission level: less connections for more security

    Mureddu, Mario; Caldarelli, Guido; Damiano, Alfonso; Scala, Antonio; Meyer-Ortmanns, Hildegard

    2016-01-01

    Islanding is known as a management procedure of the power system that is implemented at the distribution level to preserve sensible loads from outages and to guarantee the continuity in electricity supply, when a high amount of distributed generation occurs. In this paper we study islanding on the level of the transmission grid and shall show that it is a suitable measure to enhance energy security and grid resilience. We consider the German and Italian transmission grids. We remove links either randomly to mimic random failure events, or according to a topological characteristic, their so-called betweenness centrality, to mimic an intentional attack and test whether the resulting fragments are self-sustainable. We test this option via the tool of optimized DC power flow equations. When transmission lines are removed according to their betweenness centrality, the resulting islands have a higher chance of being dynamically self-sustainable than for a random removal. Less connections may even increase the grid’s stability. These facts should be taken into account in the design of future power grids. PMID:27713509

  4. A detector for monitoring the onset of cavitation during therapy-level measurements of ultrasonic power

    Hodnett, M.; Zeqiri, B.

    2004-01-01

    Acoustic cavitation occurring in the water path between a transducer and the target of a radiation force balance can provide a significant source of error during measurements of ultrasonic power. These problems can be particularly acute at physiotherapy levels (>1 W), and low frequencies (leq 1 MHz). The cavitating bubbles can absorb and scatter incident ultrasound, leading to an underestimate in the measured power. For these reasons, International Specification standards demand the use of degassed water. This imposes requirements that may actually be difficult to meet, for example, in the case of hospitals. Also, initially degassed water will rapidly re-gas, increasing the likelihood of cavitation occurring. For these reasons, NPL has developed a device that monitors acoustic emissions generated by bubble activity, for detecting the onset of cavitation during power measurements. A commercially available needle hydrophone is used to detect these emissions. The acoustic signals are then monitored using a Cavitation Detector (CD) unit, comprising an analogue electrical filter that may be tuned to detect frequency components generated by cavitating bubbles, and which provides an indication of when the measured level exceeds a pre-defined threshold. This paper describes studies to establish a suitable detection scheme, the principles of operation of the CD unit, and the performance tests carried out with a range of propagation media.

  5. Islanding the power grid on the transmission level: less connections for more security.

    Mureddu, Mario; Caldarelli, Guido; Damiano, Alfonso; Scala, Antonio; Meyer-Ortmanns, Hildegard

    2016-10-07

    Islanding is known as a management procedure of the power system that is implemented at the distribution level to preserve sensible loads from outages and to guarantee the continuity in electricity supply, when a high amount of distributed generation occurs. In this paper we study islanding on the level of the transmission grid and shall show that it is a suitable measure to enhance energy security and grid resilience. We consider the German and Italian transmission grids. We remove links either randomly to mimic random failure events, or according to a topological characteristic, their so-called betweenness centrality, to mimic an intentional attack and test whether the resulting fragments are self-sustainable. We test this option via the tool of optimized DC power flow equations. When transmission lines are removed according to their betweenness centrality, the resulting islands have a higher chance of being dynamically self-sustainable than for a random removal. Less connections may even increase the grid's stability. These facts should be taken into account in the design of future power grids.

  6. Global Sea Level Stabilization-Sand Dune Fixation: A Solar-powered Sahara Seawater Textile Pipeline

    Badescu, Viorel; Bolonkin, Alexander A

    2007-01-01

    Could anthropogenic saturation with pumped seawater of the porous ground of active sand dune fields in major deserts (e.g., the westernmost Sahara) cause a beneficial reduction of global sea level? Seawater extraction from the ocean, and its deposition on deserted sand dune fields in Mauritania and elsewhere via a Solar-powered Seawater Textile Pipeline (SSTP) can thwart the postulated future global sea level. Thus, Macro-engineering offers an additional cure for anticipated coastal change, driven by global sea level rise, that could supplement, or substitute for (1) stabilizing the shoreline with costly defensive public works (armoring macroprojects) and (2) permanent retreat from the existing shoreline (real and capital property abandonment). We propose Macro-engineering use tactical technologies that sculpt and vegetate barren near-coast sand dune fields with seawater, seawater that would otherwise, as commonly postulated, enlarge Earth seascape area! Our Macro-engineering speculation blends eremology with...

  7. High power RF system for transverse deflecting structure XFEL TDS INJ

    Volobuev, E. N.; Zavadtsev, A. A.; Zavadtsev, D. A.; Smirnov, A. J.; Sobenin, N. P.; Churanov, D. V.

    2016-09-01

    The high power RF system (HPRF) is designed for RF feeding of the transverse deflecting structure of the transverse deflecting system XFEL TDS System INJ of the European X-ray Free Electron Laser. The HPRF system includes klystron, waveguide ceramic windows, directional couplers, waveguide vacuum units, spark detector and waveguide line. Operating frequency is 2997.2 MHz. Peak input power is up to 3 MW. The HPRF system has been developed, manufactured and assembled in the XFEL Injector building. The total length of the waveguide line is 55 m from the klystron at the -5 floor to the transverse deflecting structure at the -7 floor. All designed RF parameters have been obtained experimentally at low RF power level.

  8. Powered ankle-foot prosthesis to assist level-ground and stair-descent gaits.

    Au, Samuel; Berniker, Max; Herr, Hugh

    2008-05-01

    The human ankle varies impedance and delivers net positive work during the stance period of walking. In contrast, commercially available ankle-foot prostheses are passive during stance, causing many clinical problems for transtibial amputees, including non-symmetric gait patterns, higher gait metabolism, and poorer shock absorption. In this investigation, we develop and evaluate a myoelectric-driven, finite state controller for a powered ankle-foot prosthesis that modulates both impedance and power output during stance. The system employs both sensory inputs measured local to the external prosthesis, and myoelectric inputs measured from residual limb muscles. Using local prosthetic sensing, we first develop two finite state controllers to produce biomimetic movement patterns for level-ground and stair-descent gaits. We then employ myoelectric signals as control commands to manage the transition between these finite state controllers. To transition from level-ground to stairs, the amputee flexes the gastrocnemius muscle, triggering the prosthetic ankle to plantar flex at terminal swing, and initiating the stair-descent state machine algorithm. To transition back to level-ground walking, the amputee flexes the tibialis anterior muscle, triggering the ankle to remain dorsiflexed at terminal swing, and initiating the level-ground state machine algorithm. As a preliminary evaluation of clinical efficacy, we test the device on a transtibial amputee with both the proposed controller and a conventional passive-elastic control. We find that the amputee can robustly transition between the finite state controllers through direct muscle activation, allowing rapid transitioning from level-ground to stair walking patterns. Additionally, we find that the proposed finite state controllers result in a more biomimetic ankle response, producing net propulsive work during level-ground walking and greater shock absorption during stair descent. The results of this study highlight the

  9. Radioactivity level of the ambient environment of Anren bone-coal power station

    2002-01-01

    The radioactivity level of the ambient environment of Anren Bonc-coalPower Station (BCPS) was investigated systematically. The γ radiation dose ratelevel in the environment, the content of 238U and 226Ra in the ambient soil and thefarmland in the direction of downwind, the concentrations of 238U, 232Th, 226Ra, 40Kand 222Rn, as well as α potential energy in air, and the concentrations of natural Uand Th in effluent are all higher than the corresponding values of the reference site.The additional annual effective dose equivalent to the residents living in the housesmade of bone-coal cinder brick is 2.7mSv.

  10. Modeling of Busbars in High Power Neutral Point Clamped Three-Level Inverters

    YI Rung; ZHAO Zhengming; ZHONG Yulin

    2008-01-01

    The busbars in high power neutral point clamped three-level inverters are modeled using the Maxwell Q3D Extractor software, which is based on the partial element equivalent circuits method. The equivalent circuits of the busbars and devices model are simulated in the electric simulator PSIM to analyze the effects of the parasitic inductance on the switching characteristics of the integrated gate commutatedthyristor (IGCT) in different topology positions. The simulation results agree well with the measured imped-ance analyzer results and the IGCT test results, which proves the effectiveness of the modeling method for the large, complex busbars.

  11. Smart energy management and low-power design of sensor and actuator nodes on algorithmic level for self-powered sensorial materials and robotics

    Bosse, Stefan; Behrmann, Thomas

    2011-06-01

    We propose and demonstrate a design methodology for embedded systems satisfying low power requirements suitable for self-powered sensor and actuator nodes. This design methodology focuses on 1. smart energy management at runtime and 2. application-specific System-On- Chip (SoC) design at design time, contributing to low-power systems on both algorithmic and technology level. Smart energy management is performed spatially at runtime by a behaviour-based or state-action-driven selection from a set of different (implemented) algorithms classified by their demand of computation power, and temporally by varying data processing rates. It can be shown that power/energy consumption of an application-specific SoC design depends strongly on computation complexity. Signal and control processing is modelled on abstract level using signal flow diagrams. These signal flow graphs are mapped to Petri Nets to enable direct high-level synthesis of digital SoC circuits using a multi-process architecture with the Communicating-Sequential-Process model on execution level. Power analysis using simulation techniques on gatelevel provides input for the algorithmic selection during runtime of the system, leading to a closed-loop design flow. Additionally, the signal-flow approach enables power management by varying the signal flow and data processing rates depending on actual energy consumption, estimated energy deposit, and required Quality-of-Service.

  12. Study and Analysis of a Natural Reference Frame Current Controller for a Multi-Level H-Bridge Power Converter

    Ciobotaru, Mihai; Iov, Florin; Zanchetta, P.;

    2008-01-01

    will be needed in order to control the power flow and to ensure proper and secure operation of this future grid with an increased level of renewable power. These power converters must be able to provide intelligent power management as well as ancillary services. This paper presents an analysis of the natural...... reference frame controller, based on proportional-resonant (PR) technique, for a multi-level H-bridge power converter for Universal and Flexible Power Management in Future Electricity Network. The proposed method is tested in terms of harmonic content in the Point of Common Coupling (PCC), voltage......To pave the way to a sustainable energy future based on a larger share of Distributed Generation (DG), there is a clear need to prepare the European electricity system for the large-scale integration of both renewable and other distributed energy sources. Advanced power electronic converters for DG...

  13. Modeling Photovoltaic Module-Level Power Electronics in the System Advisor Model; NREL (National Renewable Energy Laboratory)

    None

    2015-07-01

    Module-level power electronics, such as DC power optimizers, microinverters, and those found in AC modules, are increasing in popularity in smaller-scale photovoltaic (PV) systems as their prices continue to decline. Therefore, it is important to provide PV modelers with guidelines about how to model these distributed power electronics appropriately in PV modeling software. This paper extends the work completed at NREL that provided recommendations to model the performance of distributed power electronics in NREL’s popular PVWatts calculator [1], to provide similar guidelines for modeling these technologies in NREL's more complex System Advisor Model (SAM). Module-level power electronics - such as DC power optimizers, microinverters, and those found in AC modules-- are increasing in popularity in smaller-scale photovoltaic (PV) systems as their prices continue to decline. Therefore, it is important to provide PV modelers with guidelines about how to model these distributed power electronics appropriately in PV modeling software.

  14. Application of Backstepping to the Virtual Flux Direct Power Control of Five-Level Three-Phase Shunt Active Power Filter

    Bouzidi Mansour

    2014-03-01

    Full Text Available This paper proposes a virtual flux direct power control-space vector modulation combined with backstepping control for three-phase five-level neutral point clamped shunt active power filter. The main goal of the proposed active filtering system is to eliminate the unwanted harmonics and compensate fundamental reactive power drawn from the nonlinear loads. In this study, the voltage-balancing control of four split dc capacitors of the five-level active filter is achieved using five-level space vector modulation with balancing strategy based on the effective use of the redundant switching states of the inverter voltage vectors. The obtained results showed that, the proposed multilevel shunt active power filter with backstepping control can produce a sinusoidal supply current with low harmonic distortion and in phase with the line voltage.

  15. Allowable Residual Contamination Levels in soil for decommissioning the Shippingport Atomic Power Station site

    Kennedy, W.E. Jr.; Napier, B.A.; Soldat, J.K.

    1983-09-01

    As part of decommissioning the Shippingport Atomic Power Station, a fundamental concern is the determination of Allowable Residual Contamination Levels (ARCL) for radionuclides in the soil at the site. The ARCL method described in this report is based on a scenario/exposure-pathway analysis and compliance with an annual dose limit for unrestricted use of the land after decommissioning. In addition to naturally occurring radionuclides and fallout from weapons testing, soil contamination could potentially come from five other sources. These include operation of the Shippingport Station as a pressurized water reactor, operations of the Shippingport Station as a light-water breeder, operation of the nearby Beaver Valley reactors, releases during decommissioning, and operation of other nearby industries, including the Bruce-Mansfield coal-fired power plants. ARCL values are presented for 29 individual radionculides and a worksheet is provided so that ARCL values can be determined for any mixture of the individual radionuclides for any annual dose limit selected. In addition, a worksheet is provided for calculating present time soil concentration value that will decay to the ARCL values after any selected period of time, such as would occur during a period of restricted access. The ARCL results are presented for both unconfined (surface) and confined (subsurface) soil contamination. The ARCL method and results described in this report provide a flexible means of determining unrestricted-use site release conditions after decommissioning the Shippingport Atomic Power Station.

  16. What day-ahead reserves are needed in electric grids with high levels of wind power?

    Mauch, Brandon; Apt, Jay; Carvalho, Pedro M. S.; Jaramillo, Paulina

    2013-09-01

    Day-ahead load and wind power forecasts provide useful information for operational decision making, but they are imperfect and forecast errors must be offset with operational reserves and balancing of (real time) energy. Procurement of these reserves is of great operational and financial importance in integrating large-scale wind power. We present a probabilistic method to determine net load forecast uncertainty for day-ahead wind and load forecasts. Our analysis uses data from two different electric grids in the US with similar levels of installed wind capacity but with large differences in wind and load forecast accuracy, due to geographic characteristics. We demonstrate that the day-ahead capacity requirements can be computed based on forecasts of wind and load. For 95% day-ahead reliability, this required capacity ranges from 2100 to 5700 MW for ERCOT, and 1900 to 4500 MW for MISO (with 10 GW of installed wind capacity), depending on the wind and load forecast values. We also show that for each MW of additional wind power capacity for ERCOT, 0.16-0.30 MW of dispatchable capacity will be used to compensate for wind uncertainty based on day-ahead forecasts. For MISO (with its more accurate forecasts), the requirement is 0.07-0.13 MW of dispatchable capacity for each MW of additional wind capacity.

  17. On-chip power-combining techniques for watt-level linear power amplifiers in 0.18 μm CMOS

    Zhixiong, Ren; Kefeng, Zhang; Lanqi, Liu; Cong, Li; Xiaofei, Chen; Dongsheng, Liu; Zhenglin, Liu; Xuecheng, Zou

    2015-09-01

    Three linear CMOS power amplifiers (PAs) with high output power (more than watt-level output power) for high data-rate mobile applications are introduced. To realize watt-level output power, there are two 2.4 GHz PAs using an on-chip parallel combining transformer (PCT) and one 1.95 GHz PA using an on-chip series combining transformer (SCT) to combine output signals of multiple power stages. Furthermore, some linearization techniques including adaptive bias, diode linearizer, multi-gated transistors (MGTR) and the second harmonic control are applied in these PAs. Using the proposed power combiner, these three PAs are designed and fabricated in TSMC 0.18 μm RFCMOS process. According to the measurement results, the proposed two linear 2.4 GHz PAs achieve a gain of 33.2 dB and 34.3 dB, a maximum output power of 30.7 dBm and 29.4 dBm, with 29% and 31.3% of peak PAE, respectively. According to the simulation results, the presented linear 1.95 GHz PA achieves a gain of 37.5 dB, a maximum output power of 34.3 dBm with 36.3% of peak PAE. Project supported by the National Natural Science Foundation of China (No. 61076030).

  18. A Battery-less Grid Connected Photovoltaic Power generation using Five-Level Common-Emitter Current-Source Inverter

    Suroso Suroso

    2014-12-01

    Full Text Available Renewable power generation using photovoltaic is very interesting to be developed to deal with the problems of conventional energy sources and environmental issues. The photovoltaic power generation can operate both in stand-alone and grid-connected operations. This paper presents an application of the five-level common-emitter current-source inverter (CE-CSI for grid connected photovoltaic system without batteries as energy storage system. In the proposed system, the five-level CE-CSI works generating a sinusoidal output current from photovoltaic system to be injected into the power grid. The transformer is used in the system to step-down the grid voltage to meet the voltage level of the photovoltaic system, and also works as a galvanic insulation between the power grid and the inverter system. Two conditions of the power grid voltage, i.e. a pure sinusoidal and a distorted power grid, are tested through computer simulation using PSIM software. Furthermore, experimental test result of the five-level inverter is also presented. The test results show that the five-level CE-CSI works well injecting a sinusoidal current into the power grid with low harmonic contents, and with unity power factor operation. The results also show that the distorted grid voltage affects the harmonic contents of the current injected by the inverter.

  19. Towards a communication-theoretic understanding of system-level power consumption

    Grover, Pulkit; Sahai, Anant

    2010-01-01

    Traditional communication theory focuses on minimizing transmit power. Increasingly, however, communication links are operating at shorter ranges where transmit power can drop below the power consumed in decoding. In this paper, we model the required decoding power and investigate the minimization of total system power from two complementary perspectives. First, an isolated point-to-point link is considered. Using new lower bounds on the complexity of message-passing decoding, lower bounds are derived on decoding power. These bounds show that 1) there is a fundamental tradeoff between transmit and decoding power; 2) unlike the implications of the traditional ``waterfall'' curve which focuses on transmit power, the total power must diverge to infinity as error probability goes to zero; 3) Regular LDPCs, and not their capacity-achieving counterparts, can be shown to be power order optimal in some cases; and 4) the optimizing transmit power is bounded away from the Shannon limit. Second, we consider a collection...

  20. Fourier power spectrum characteristics of face photographs: attractiveness perception depends on low-level image properties.

    Menzel, Claudia; Hayn-Leichsenring, Gregor U; Langner, Oliver; Wiese, Holger; Redies, Christoph

    2015-01-01

    We investigated whether low-level processed image properties that are shared by natural scenes and artworks - but not veridical face photographs - affect the perception of facial attractiveness and age. Specifically, we considered the slope of the radially averaged Fourier power spectrum in a log-log plot. This slope is a measure of the distribution of special frequency power in an image. Images of natural scenes and artworks possess - compared to face images - a relatively shallow slope (i.e., increased high spatial frequency power). Since aesthetic perception might be based on the efficient processing of images with natural scene statistics, we assumed that the perception of facial attractiveness might also be affected by these properties. We calculated Fourier slope and other beauty-associated measurements in face images and correlated them with ratings of attractiveness and age of the depicted persons (Study 1). We found that Fourier slope - in contrast to the other tested image properties - did not predict attractiveness ratings when we controlled for age. In Study 2A, we overlaid face images with random-phase patterns with different statistics. Patterns with a slope similar to those in natural scenes and artworks resulted in lower attractiveness and higher age ratings. In Studies 2B and 2C, we directly manipulated the Fourier slope of face images and found that images with shallower slopes were rated as more attractive. Additionally, attractiveness of unaltered faces was affected by the Fourier slope of a random-phase background (Study 3). Faces in front of backgrounds with statistics similar to natural scenes and faces were rated as more attractive. We conclude that facial attractiveness ratings are affected by specific image properties. An explanation might be the efficient coding hypothesis.

  1. Fourier power spectrum characteristics of face photographs: attractiveness perception depends on low-level image properties.

    Claudia Menzel

    Full Text Available We investigated whether low-level processed image properties that are shared by natural scenes and artworks - but not veridical face photographs - affect the perception of facial attractiveness and age. Specifically, we considered the slope of the radially averaged Fourier power spectrum in a log-log plot. This slope is a measure of the distribution of special frequency power in an image. Images of natural scenes and artworks possess - compared to face images - a relatively shallow slope (i.e., increased high spatial frequency power. Since aesthetic perception might be based on the efficient processing of images with natural scene statistics, we assumed that the perception of facial attractiveness might also be affected by these properties. We calculated Fourier slope and other beauty-associated measurements in face images and correlated them with ratings of attractiveness and age of the depicted persons (Study 1. We found that Fourier slope - in contrast to the other tested image properties - did not predict attractiveness ratings when we controlled for age. In Study 2A, we overlaid face images with random-phase patterns with different statistics. Patterns with a slope similar to those in natural scenes and artworks resulted in lower attractiveness and higher age ratings. In Studies 2B and 2C, we directly manipulated the Fourier slope of face images and found that images with shallower slopes were rated as more attractive. Additionally, attractiveness of unaltered faces was affected by the Fourier slope of a random-phase background (Study 3. Faces in front of backgrounds with statistics similar to natural scenes and faces were rated as more attractive. We conclude that facial attractiveness ratings are affected by specific image properties. An explanation might be the efficient coding hypothesis.

  2. A General Framework for Power Analysis to Detect the Moderator Effects in Two- and Three-Level Cluster Randomized Trials

    Dong, Nianbo; Spybrook, Jessaca; Kelcey, Ben

    2016-01-01

    The purpose of this study is to propose a general framework for power analyses to detect the moderator effects in two- and three-level cluster randomized trials (CRTs). The study specifically aims to: (1) develop the statistical formulations for calculating statistical power, minimum detectable effect size (MDES) and its confidence interval to…

  3. On the Efficiency of a Two-Power-Level Flywheel-Based All-Electric Driveline

    Hans Bernhoff

    2012-08-01

    Full Text Available This paper presents experimental results on an innovative electric driveline employing a kinetic energy storage device as energy buffer. A conceptual division of losses in the system was created, separating the complete system into three parts according to their function. This conceptualization of the system yielded a meaningful definition of the concept of efficiency. Additionally, a thorough theoretical framework for the prediction of losses associated with energy storage and transfer in the system was developed. A large number of spin-down tests at varying pressure levels were performed. A separation of the measured data into the different physical processes responsible for power loss was achieved from the corresponding dependence on rotational velocity. This comparison yielded an estimate of the perpendicular resistivity of the stranded copper conductor of 2.5 × 10−8 ± 3.5 × 10−9. Further, power and energy were measured system-wide during operation, and an analysis of the losses was performed. The analytical solution was able to reproduce the measured distribution of losses in the system to an accuracy of 4.7% (95% CI. It was found that the losses attributed to the function of kinetic energy storage in the system amounted to between 45% and 65%, depending on usage.

  4. Levelized Cost of Energy Analysis of a Wind Power Generation System at Búrfell in Iceland

    Birgir Freyr Ragnarsson

    2015-09-01

    Full Text Available Wind energy harnessing is a new energy production alternative in Iceland. Current installed wind power in Iceland sums to 1.8 MW, which in contrast is 0.1% of the country’s total electricity production. This article is dedicated to the exploration of the potential cost of wind energy production at Búrfell in the south of Iceland. A levelized cost of energy (LCOE approach was applied to the estimation of the potential cost. Weibull simulation is used to simulate wind data for calculations. A confirmation of the power law is done by comparing real data to calculated values. A modified Weibull simulation is verified by comparing results with actual on-site test wind turbines. A wind farm of 99MWis suggested for the site. Key results were the capacity factor (CF at Búrfell being 38.15% on average and that the LCOE for wind energy was estimated as 0.087–0.088 USD/kWh (assuming 10% weighted average cost of capital (WACC, which classifies Búrfell among the lowest LCOE sites for wind energy in Europe.

  5. A Demonstration of Spectral Level Reconstruction of Intrinsic $B$-mode Power

    Pal, Barun

    2016-01-01

    We investigate the prospects and consequences of the spectral level reconstruction of primordial $B$-mode power by solving the systems of linear equations assuming that the lensing potential together with the lensed polarization spectra are already in hand. We find that this reconstruction technique may be very useful to have an estimate of the amplitude of primordial gravity waves or more specifically the value of tensor to scalar ratio. We also see that one can have cosmic variance limited reconstruction of the intrinsic $B$-mode power up to few hundred multipoles ($\\ell\\sim500$) which is more than sufficient to have an estimate of the tensor to scalar ratio. Since the small scale cosmic microwave background (CMB henceforth) anisotropies are not sourced by the primordial gravity waves generated during inflation. We also find that the impact of instrumental noise may be bypassed within this reconstruction algorithm. A simple demonstration for the nullification of the instrumental noise anticipating COrE like...

  6. Power

    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...

  7. Large Wind Energy Converter: Growian 3 MW

    Feustel, J. E.; Helm, S.; Koerber, F.

    1980-01-01

    The final report on the projected application of larger-scale wind turbine on the northern German coast is summarized. The designs of the tower, machinery housing, rotor, and rotor blades are described accompanied various construction materials are examined. Rotor blade adjustment devices auxiliary and accessory equipment are examined.

  8. Gross β activity level of fallout in the environment around Qinshan Nuclear Power Plant

    YE Ji-Da; CHEN Bin; WU Zong-Mei

    2005-01-01

    This paper presents the measurement results of gross β activities in fallout samples collected from the environment around Qinshan Nuclear Power Plant (NPP) during 1993-2002. The gross β activity of 191 samples collected at five monitoring spots were (0.11~3.64) Bq · m-2 · d-1, with an average of (0.91 ±0.49) Bq · m-2 · d-1. This value was lower than (1.02±0.35) Bq·m-2·d-1 , the average of the samples collected at the reference spot in Hangzhou.It indicated that no obvious rise in the gross β activity level of fallout was observed in ambience of Qinshan NPP.

  9. Four Key Keys to Powerful Presentations in PowerPoint: Take Your Presentations to the Next Level

    Howell, Dusti D.

    2008-01-01

    If a person is on a presentation and he/she does not know how to go back to a previous PowerPoint slide, his/her credibility will be clouded and the audience will become frustrated. More sophisticated presenters use handheld remotes to control the basic navigation of slides. Even in this case, keyboard shortcuts can be an added benefit. For those…

  10. Design for Reliability of Power Electronic Systems

    Wang, Huai; Ma, Ke; Blaabjerg, Frede

    2012-01-01

    Advances in power electronics enable efficient and flexible processing of electric power in the application of renewable energy sources, electric vehicles, adjustable-speed drives, etc. More and more efforts are devoted to better power electronic systems in terms of reliability to ensure high...... on a 2.3 MW wind power converter is discussed with emphasis on the reliability critical components IGBTs. Different aspects of improving the reliability of the power converter are mapped. Finally, the challenges and opportunities to achieve more reliable power electronic systems are addressed....

  11. Minimizing the Levelized Cost of Energy in Single-Phase Photovoltaic Systems with an Absolute Active Power Control

    Yang, Yongheng; Koutroulis, Eftichios; Sangwongwanich, Ariya

    2015-01-01

    control strategy, the Absolute Active Power Control (AAPC) can effectively solve the overloading issues by limiting the maximum possible PV power to a certain level (i.e., the power limitation), and also benefit the inverter reliability. However, its feasibility is challenged by the energy loss....... An increase of the inverter lifetime and a reduction of the energy yield can alter the cost of energy, demanding an optimization of the power limitation. Therefore, aiming at minimizing the Levelized Cost of Energy (LCOE), the power limit is optimized for the AAPC strategy in this paper. The optimization...... method is demonstrated on a 3-kW single-phase PV system considering a real-field mission profile (i.e., solar irradiance and ambient temperature). The optimization results have revealed that superior performance in terms of LCOE and energy production can be obtained by enabling the AAPC strategy...

  12. Output Feedback Dissipation Control for the Power-Level of Modular High-Temperature Gas-Cooled Reactors

    Zhe Dong

    2011-11-01

    Full Text Available Because of its strong inherent safety features and the high outlet temperature, the modular high temperature gas-cooled nuclear reactor (MHTGR is the chosen technology for a new generation of nuclear power plants. Such power plants are being considered for industrial applications with a wide range of power levels, thus power-level regulation is very important for their efficient and stable operation. Exploiting the large scale asymptotic closed-loop stability provided by nonlinear controllers, a nonlinear power-level regulator is presented in this paper that is based upon both the techniques of feedback dissipation and well-established backstepping. The virtue of this control strategy, i.e., the ability of globally asymptotic stabilization, is that it takes advantage of the inherent zero-state detectability property of the MHTGR dynamics. Moreover, this newly built power-level regulator is also robust towards modeling uncertainty in the control rod dynamics. If modeling uncertainty of the control rod dynamics is small enough to be omitted, then this control law can be simplified to a classical proportional feedback controller. The comparison of the control performance between the newly-built power controller and the simplified controller is also given through numerical study and theoretical analysis.

  13. The effects of a maximal power training cycle on the strength, maximum power, vertical jump height and acceleration of high-level 400-meter hurdlers.

    Balsalobre-Fernández, Carlos; Tejero-González, Carlos M; Del Campo-Vecino, Juan; Alonso-Curiel, Dionisio

    2013-03-01

    The aim of this study was to determine the effects of a power training cycle on maximum strength, maximum power, vertical jump height and acceleration in seven high-level 400-meter hurdlers subjected to a specific training program twice a week for 10 weeks. Each training session consisted of five sets of eight jump-squats with the load at which each athlete produced his maximum power. The repetition maximum in the half squat position (RM), maximum power in the jump-squat (W), a squat jump (SJ), countermovement jump (CSJ), and a 30-meter sprint from a standing position were measured before and after the training program using an accelerometer, an infra-red platform and photo-cells. The results indicated the following statistically significant improvements: a 7.9% increase in RM (Z=-2.03, p=0.021, δc=0.39), a 2.3% improvement in SJ (Z=-1.69, p=0.045, δc=0.29), a 1.43% decrease in the 30-meter sprint (Z=-1.70, p=0.044, δc=0.12), and, where maximum power was produced, a change in the RM percentage from 56 to 62% (Z=-1.75, p=0.039, δc=0.54). As such, it can be concluded that strength training with a maximum power load is an effective means of increasing strength and acceleration in high-level hurdlers.

  14. A RESEARCH TO HIGH-PERFORMANCE MULTI-LEVEL SINGLEPHASE AC/DC POWER FACTOR CORRECT SWITCHING CONVERTER

    Gao Chao

    2008-01-01

    This letter studies and analyzes the working features of main circuit of tri-level boost Power Factor Correct (PFC) converter and the advantages of tri-level switch converter in aspects of bearing high-voltage of power components,overall system loss and magnetic component selection based upon the single-level boost PFC switch converter. Besides,relying on the application of mi-croprocessor in power converter technology and DSP (Digital Signal Processing) chip's strong cal-culating capacity,the letter presents the adoption of modified scheme of tri-level boost PFC converter under the control of predictive control algorithm. Moreover,the operating principle and control method are specified,the results of circuit test and analysis are provided and the advantages of pre-dictive control technology-based multi-level boost PFC converter is verified.

  15. Optimization of Electric Power Leveling Systems by a Novel Hybrid Algorithm with Simulated Evolution and Genetic Algorithms

    Itoh, Jyunpei; Yamamoto, Masayoshi; Funabiki, Shigeyuki

    Electric power demand has an increasing tendency year by year. The fluctuation of the electric power causes further increase in the cost of the electric power facility and electricity charges. The development of the electric power-leveling systems (EPLS) using energy storage technology is desired to improve the electric power quality. The EPLS with a SMES is proposed as one of the countermeasures for the electric power quality improvement. However, the SMES is very expensive and it is difficult to decide the gains of the controller. It is essential in the practical use that the reduction of SMES capacity is realized. This paper proposes a new optimization method of the EPLS. The proposed algorithm is hybrid architecture with a combination of SimE (Simulated Evolution) and GA (Genetic Algorithms). The optimization of the EPLS can be achieved by the proposed hybrid algorithm compared to the SimE and the GA.

  16. Operation and thermal loading of three-level Neutral-Point-Clamped wind power converter under various grid faults

    Ma, Ke; Blaabjerg, Frede; Liserre, Marco

    2012-01-01

    Ride Through (LVRT) operation under grid faults, may compromise the reliability of the system and consequently further increase its cost. In this paper, the impact of various grid faults on a three-level Neutral-Point-Clamped (3L-NPC) grid-converter in terms of thermal loading of power semiconductor......In order to fulfill the continuous growing grid-side demands, the full-scale power converters are becoming more and more popular in the wind power application. Nevertheless, the more severe loading of the power semiconductor devices in the full-scale power converters, especially during Low Voltage...... devices is highlighted. It has been found that the thermal loading of the phases of the power converter may be uneven and dependent on the different types and severities of grid voltage dips as well as on the chosen control algorithms....

  17. Dose estimation for nuclear power plant 4 accident in Taiwan at Fukushima nuclear meltdown emission level.

    Tang, Mei-Ling; Tsuang, Ben-Jei; Kuo, Pei-Hsuan

    2016-05-01

    An advanced Gaussian trajectory dispersion model is used to evaluate the evacuation zone due to a nuclear meltdown at the Nuclear Power Plant 4 (NPP4) in Taiwan, with the same emission level as that occurred at Fukushima nuclear meltdown (FNM) in 2011. Our study demonstrates that a FNM emission level would pollute 9% of the island's land area with annual effective dose ≥50 mSv using the meteorological data on 11 March 2011 in Taiwan. This high dose area is also called permanent evacuation zone (denoted as PEZ). The PEZ as well as the emergency-planning zone (EPZ) are found to be sensitive to meteorological conditions on the event. In a sunny day under the dominated NE wind conditions, the EPZ can be as far as 100 km with the first 7-day dose ≥20 mSv. Three hundred sixty-five daily events using the meteorological data from 11 March 2011 to 9 March 2012 are evaluated. It is found that the mean land area of Taiwan in becoming the PEZ is 11%. Especially, the probabilities of the northern counties/cities (Keelung, New Taipei, Taipei, Taoyuan, Hsinchu City, Hsinchu County and Ilan County) to be PEZs are high, ranging from 15% in Ilan County to 51% in Keelung City. Note that the total population of the above cities/counties is as high as 10 million people. Moreover, the western valleys of the Central Mountain Range are also found to be probable being PEZs, where all of the reservoirs in western Taiwan are located. For example, the probability can be as high as 3% in the far southern-most tip of Taiwan Island in Pingtung County. This shows that the entire populations in western Taiwan can be at risk due to the shortage of clean water sources under an event at FNM emission level, especially during the NE monsoon period.

  18. Improving packaging and increasing the level of integration in power electronics

    Popovic, J.

    2005-01-01

    The use of power electronics is growing extensively in applications such as the automotive field, lighting, power supplies, motor drives, etc. The ultimate goal is to make power electronics as transparent to the final user as possible, which means little extra cost, use of existing space and little

  19. Deconstructing the power resistance relationship for squats: A joint-level analysis.

    Farris, D J; Lichtwark, G A; Brown, N A T; Cresswell, A G

    2016-07-01

    Generating high leg power outputs is important for executing rapid movements. Squats are commonly used to increase leg strength and power. Therefore, it is useful to understand factors affecting power output in squatting. We aimed to deconstruct the mechanisms behind why power is maximized at certain resistances in squatting. Ten male rowers (age = 20 ± 2.2 years; height = 1.82 ± 0.03 m; mass = 86 ± 11 kg) performed maximal power squats with resistances ranging from body weight to 80% of their one repetition maximum (1RM). Three-dimensional kinematics was combined with ground reaction force (GRF) data in an inverse dynamics analysis to calculate leg joint moments and powers. System center of mass (COM) velocity and power were computed from GRF data. COM power was maximized across a range of resistances from 40% to 60% 1RM. This range was identified because a trade-off in hip and knee joint powers existed across this range, with maximal knee joint power occurring at 40% 1RM and maximal hip joint power at 60% 1RM. A non-linear system force-velocity relationship was observed that dictated large reductions in COM power below 20% 1RM and above 60% 1RM. These reductions were due to constraints on the control of the movement.

  20. Ordering Power of Separate versus Grouped True-False Tests: Interaction of Type of Test with Knowledge Levels of Examinees.

    Hsu, Louis M.

    1979-01-01

    A comparison of the relative ordering power of separate and grouped-items true-false tests indicated that neither type of test was uniformly superior to the other across all levels of knowledge of examinees. Grouped-item tests were found superior for examinees with low levels of knowledge. (Author/CTM)

  1. The new voltage level 48 V for vehicle power supply; Die neue Spannungsebene 48 V im Kraftfahrzeug

    Doersam, Thomas [Daimler AG, Boeblingen (Germany). Bordnetzkonzepte; Kehl, Steffen [Porsche Aktiengesellschaft, Weissach (Germany). Sachgebiet verteilte Funktionen elektrische Energie und Verbrauch; Klinkig, Andreas [Volkswagen AG, Wolfsburg (Germany). Energiemanagement; Radon, Andre [Audi AG, Ingolstadt (Germany). Bordnetzkonzepte und Energieeffizienz; Sirch, Ottmar [BMW Group, Muenchen (Germany). Vorentwicklung Energiebordnetz

    2012-02-15

    The increasing requirements to the vehicle power supply in conventional cars have taken the 12 V power supply to its limits. The car manufacturers Audi, BMW, Daimler, Porsche and Volkswagen were aware of this subject very early and worked out a first specification for a second voltage level at 48 V. The OEMs explain the conditions and backgrounds for deriving the voltage range and the concepts, the tests and test conditions for any components which will be applied in this voltage level. Additionally, the car manufacturers describe the probably next milestones for standardization and the standard of the voltage level as well as some potential E/E architecture concepts. (orig.)

  2. Levels of community engagement in youth violence prevention: the role of power in sustaining successful university-community partnerships.

    Nation, Maury; Bess, Kimberly; Voight, Adam; Perkins, Douglas D; Juarez, Paul

    2011-09-01

    Previous research indicates that communities can be engaged at various levels in research to reduce youth violence. In this paper, we argue that the method of power sharing among partners is a central factor distinguishing different levels of engagement. Using cases from the Nashville Urban Partnership Academic Center of Excellence, we identify community initiation and community collaboration as distinct approaches to community engaged violence prevention research. The power relationships among partners are analyzed to highlight differences in the types of engagement and to discuss implications for establishing and sustaining community partnerships. Also, the implications of levels of engagement for promoting the use of evidence-based practices are discussed.

  3. An Artificial Neural Network Compensated Output Feedback Power-Level Control for Modular High Temperature Gas-Cooled Reactors

    Zhe Dong

    2014-02-01

    Full Text Available Small modular reactors (SMRs could be beneficial in providing electricity power safely and also be viable for applications such as seawater desalination and heat production. Due to its inherent safety features, the modular high temperature gas-cooled reactor (MHTGR has been seen as one of the best candidates for building SMR-based nuclear power plants. Since the MHTGR dynamics display high nonlinearity and parameter uncertainty, it is necessary to develop a nonlinear adaptive power-level control law which is not only beneficial to the safe, stable, efficient and autonomous operation of the MHTGR, but also easy to implement practically. In this paper, based on the concept of shifted-ectropy and the physically-based control design approach, it is proved theoretically that the simple proportional-differential (PD output-feedback power-level control can provide asymptotic closed-loop stability. Then, based on the strong approximation capability of the multi-layer perceptron (MLP artificial neural network (ANN, a compensator is established to suppress the negative influence caused by system parameter uncertainty. It is also proved that the MLP-compensated PD power-level control law constituted by an experientially-tuned PD regulator and this MLP-based compensator can guarantee bounded closed-loop stability. Numerical simulation results not only verify the theoretical results, but also illustrate the high performance of this MLP-compensated PD power-level controller in suppressing the oscillation of process variables caused by system parameter uncertainty.

  4. MONSTROUS HAZARDS PRODUCED BY HIGH RADIOACTIVITY LEVELS AROUND ASSIUT THERMAL POWER PLANT

    Hany El-Gamal

    2013-01-01

    Full Text Available The natural radioactivity level of heavy oil, ash and soil samples around Assiut Thermal Power Plant (ATPP in Egypt was determined using gamma ray spectrometry. The average concentrations of 226Ra, 232Th and 40K in fly ash were found to be 2307±143, 1281±80 and 1218±129 Bq kg-1, respectively, while the corresponding values in soil samples were 2670±107, 1401±78 and 1495±100 Bq kg-1, respectively. These are extremely high and higher by several orders of magnitude than the worldwide population-weighted average values in soil. The radium equivalent activity, the air absorbed dose rate, external hazard index and the annual effective dose rate were calculated and compared with the international recommended values. All averages of these parameters are much higher by several orders of magnitude than the international recommended values, indicating significant radiological health hazards around ATPP due to the radionuclides in the soil. Moreover, the water samples investigated have high activity concentrations indicating that the water is highly contaminated with radioactive materials. The results of the current study highlight the severity of this radioactive pollution on the population in the vicinity of ATPP.

  5. Costs of reducing water use of concentrating solar power to sustainable levels: Scenarios for North Africa

    Damerau, Kerstin, E-mail: damerau@iiasa.ac.at [International Institute for Applied Systems Analysis (Austria); Williges, Keith; Patt, Anthony G. [International Institute for Applied Systems Analysis (Austria); Gauche, Paul [Department of Mechanical and Mechatronic Engineering, Stellenbosch University (South Africa)

    2011-07-15

    Concentrating solar power (CSP) has the potential to become a leading sustainable energy technology for the European electricity system. In order to reach a substantial share in the energy mix, European investment in CSP appears most profitable in North Africa, where solar potential is significantly higher than in southern Europe. As well as sufficient solar irradiance, however, the majority of today's CSP plants also require a considerable amount of water, primarily for cooling purposes. In this paper we examine water usage associated with CSP in North Africa, and the cost penalties associated with technologies that could reduce those needs. We inspect four representative sites to compare the ecological and economical drawbacks from conventional and alternative cooling systems, depending on the local environment, and including an outlook with climate change to the mid-century. Scaling our results up to a regional level indicates that the use of wet cooling technologies would likely be unsustainable. Dry cooling systems, as well as sourcing of alternative water supplies, would allow for sustainable operation. Their cost penalty would be minor compared to the variance in CSP costs due to different average solar irradiance values. - Highlights: > Scaling up CSP with wet cooling from ground water will be unsustainable in North Africa. > Desalination and alternative cooling systems can assure a sustainable water supply. > On large-scale, the cost penalties of alternative cooling technologies appear minor.

  6. Chamber wall materials response to pulsed ions at power-plant level fluences

    Renk, T. J.; Provencio, P. P.; Tanaka, T. J.; Olson, C. L.; Peterson, R. R.; Stolp, J. E.; Schroen, D. G.; Knowles, T. R.

    2005-12-01

    Candidate dry-wall materials for the reactor chambers of future laser-driven Inertial Fusion Energy (IFE) power plants have been exposed to ion pulses from RHEPP-1, located at Sandia National Laboratories. These pulses simulate the MeV-level ion pulses with fluences of up to 20 J/cm 2 that can be expected to impinge on the first wall of such future plants. Various forms of tungsten and tungsten alloy were subjected to up to 1600 pulses, usually while being heated to 600 °C. Other metals were exposed as well. Thresholds for roughening and material removal, and evolution of surface morphology were measured and compared with code predictions for materials response. Powder-metallurgy (PM) tungsten is observed to undergo surface roughening and subsurface crack formation that evolves over hundreds of pulses, and which can occur both below and above the melt threshold. This roughening is worse than for other metals, and worse than for either tungsten alloyed with rhenium (W25Re), or for CVD and single-crystal forms of tungsten. Carbon, particularly the form used in composite material, appears to suffer material loss well below its sublimation point. Some engineered materials were also investigated. It appears that some modification to PM tungsten is required for its successful use in a reactor environment.

  7. Minimizing the Levelized Cost of Energy in Single-Phase Photovoltaic Systems with an Absolute Active Power Control

    Yang, Yongheng; Koutroulis, Eftichios; Sangwongwanich, Ariya

    2017-01-01

    loading of the power devices. However, its feasibility is challenged by the associated energy losses. An increase of the inverter lifetime and a reduction of the energy yield can alter the cost of energy, demanding an optimization of the power limitation. Therefore, aiming at minimizing the Levelized Cost...... Of Energy (LCOE), the power limit is optimized for the AAPC strategy in this paper. The optimization method is demonstrated on a 3-kW single-phase PV system considering a real-field mission profile (i.e., solar irradiance and ambient temperature). The optimization results have revealed that superior...... performance in terms of LCOE and energy production can be obtained by enabling the AAPC strategy, compared to the conventional PV inverter operating only in the maximum power point tracking mode. In the presented case study, the minimum of the LCOE is achieved for the PV system when the power limit...

  8. Simulation of Standby Efficiency Improvement for a Line Level Control Resonant Converter Based on Solar Power Systems

    Ming-Tse Kuo

    2015-01-01

    Full Text Available This paper proposes a new scheme to improve the standby efficiency of the high-power half-bridge line level control (LLC resonant converter. This new circuit is applicable to improving the efficiency of the renewable energy generation system in distributed power systems. The main purpose is to achieve high-efficiency solar and wind power and stable output under different load conditions. In comparison with the traditional one, this novel method can improve standby efficiency at standby. The system characteristics of this proposed method have been analyzed through detailed simulations, which prove its feasibility.

  9. Early Experiences with Node-Level Power Capping on the Cray XC40 Platform

    Pedretti, Kevin; Olivier, Stephen Lecler; Ferreira, Kurt Brian; Shipman, Galen; Shu, Wei

    2015-10-01

    Power consumption of extreme-scale supercomputers has become a key performance bottleneck. Yet current practices do not leverage power management opportunities, instead running at ''maximum power''. This is not sustainable. Future systems will need to manage power as a critical resource, directing where it has greatest benefit. Power capping is one mechanism for managing power budgets, however its behavior is not well understood. This paper presents an empirical evaluation of several key HPC workloads running under a power cap on a Cray XC40 system, and provides a comparison of this technique with p-state control, demonstrating the performance differences of each. These results show: 1. Maximum performance requires ensuring the cap is not reached; 2. Performance slowdown under a cap can be attributed to cascading delays which result in unsynchronized performance variability across nodes; and, 3. Due to lag in reaction time, considerable time is spent operating above the set cap. This work provides a timely and much needed comparison of HPC application performance under a power cap and attempts to enable users and system administrators to understand how to best optimize application performance on power-constrained HPC systems.

  10. Thermal analysis of two-level wind power converter under symmetrical grid fault

    Zhou, Dao; Blaabjerg, Frede

    2013-01-01

    ) condition as well as the junction temperature. For the full-scale wind turbine system, the most thermal stressed power device in the grid-side converter will appear at the grid voltage below 0.5 pu, and for the partial-scale wind turbine system, the most thermal stressed power device in the rotor...

  11. Coherent Power Analysis in Multi-Level Studies Using Design Parameters from Surveys

    Rhoads, Christopher

    2016-01-01

    Current practice for conducting power analyses in hierarchical trials using survey based ICC and effect size estimates may be misestimating power because ICCs are not being adjusted to account for treatment effect heterogeneity. Results presented in Table 1 show that the necessary adjustments can be quite large or quite small. Furthermore, power…

  12. Use of Three-Level Power Converters in Wind-Driven Permanent-Magnet Synchronous Generators with Unbalanced Loads

    Ming-Hung Chen

    2015-06-01

    Full Text Available This paper describes the design and implementation of three-level power converters for wind-driven permanent-magnet synchronous generators with unbalanced loads. To increase voltage stress and reduce current harmonics in the electrical power generated by a wind generator, a three-phase, three-level rectifier is used. Because a synchronous rotating frame is used on the AC-input side, the use of a neutral-point-clamped controller is proposed to increase the power factor to unity and reduce current harmonics. Furthermore, a novel six-leg inverter is proposed for transferring energy from the DC voltage to a three-phase, four-wire AC source with a constant voltage and a constant frequency. The power converters also contain output transformers and filters for power buffering and filtering, respectively. All three output phase voltages are fed back to control the inverter output during load variations. A digital signal processor is used as the core control device for implementing a 1.5 kV, 75 kW drive system. Experimental data show that the power factor is successfully increased to unity and the total current harmonic distortion is 3.2% on the AC-input side. The entire system can attain an efficiency of 91%, and the voltage error between the upper and lower capacitors is approximately zero. Experimental results that confirm the high performance of the proposed system are presented.

  13. A Comprehensive Investigation on the Short Circuit Performance of MW-level IGBT Power Modules

    Wu, Rui; Reigosa, Paula Diaz; Iannuzzo, Francesco;

    2015-01-01

    This paper investigates the short circuit performance of commercial 1.7 kV / 1 kA IGBT power modules by means of a 6 kA Non-Destructive-Tester. A mismatched current distribution among the parallel chips has been observed, which can reduce the short circuit capability of the IGBT power module unde...... short circuit conditions. Further Spice simulations reveal that the stray parameters inside the module play an important role in contributing to such a phenomenon....

  14. System-level considerations for the front-end readout ASIC in the CBM experiment from the power supply perspective

    Kasinski, K.; Koczon, P.; Ayet, S.; Löchner, S.; Schmidt, C. J.

    2017-03-01

    New fixed target experiments using high intensity beams with energy up to 10 AGeV from the SIS100 synchrotron presently being constructed at FAIR/GSI are under preparation. Most of the readout electronics and power supplies are expected to be exposed to a very high flux of nuclear reaction products and have to be radiation tolerant up to 3 MRad (TID) and sustain up to 1014/cm2 of 1 MeV neutron equivalent in their life time. Moreover, the mostly minimum ionising particles under investigation leave very little signal in the sensors. Therefore very low noise level amplitude measurements are required by the front-end electronics for effective tracking. Sensor and interconnecting micro-cable capacitance and series resistance in conjunction with intrinsic noise of the charge sensitive amplifier are dominant noise sources in the system. However, the single-ended architecture of the amplifiers employed for the charge processing channels implies a potential problem with noise contributions from power supply sources. Strict system-level constraints leave very little freedom in selecting a power supply structure optimal with respect to: power efficiency, cooling capabilities and power density on modules, but also noise injection to the front-end via the power supply lines. Design of the power supply and distribution system of the Silicon Tracking System in the CBM experiment together with details on the front-end ASICs (STS -XYTER2) and measurement results of power supply and conditioning electronics (selected DC/DC converter and LDO regulators) are presented.

  15. Transmission Power Level Selection Method Based On Binary Search Algorithm for HiLOW

    Lingeswari V Chandra

    2011-05-01

    Full Text Available Recently the sensor communication research has introduced an IP-based communication known as 6LoWPAN to sensor network. 6LoWPAN was introduced to give a new perspective to sensor network by enabling IPv6 to be applied to wireless sensors as well as wired sensor. Dedicated routing protocols based on 6LoWPAN was soon introduced and Hierarchical Routing Protocol for 6LoWPAN (HiLOW is one of them. HiLOW clearly defines the routing tree setup process, address allocation technique and the data routing process but there is some shortcomings in terms of transmission power selection. HiLOW does not highlight how the suitable transmission power is being selected for sensor communication purpose and this leads to the assumption that at all time and all scenarios the sensors are using maximum transmission power. In the case the sensors are using maximum transmission power for communication even when it is not necessary then power depletion for sensors will be amplified and the network lifetime will be significantly reduced. In this paper we present a brief introduction to 6LoWPAN, a concise review on HiLOW, a highlight on issues revolving each process in HiLOW and propose a new idea on transmission power selection method for HiLOW.

  16. LCL filter design for three-phase two-level power factor correction using line impedance stabilization network

    Kouchaki, Alireza; Nymand, Morten

    2016-01-01

    This paper presents LCL filter design method for three-phase two-level power factor correction (PFC) using line impedance stabilization network (LISN). A straightforward LCL filter design along with variation in grid impedance is not simply achievable and inevitably lead to an iterative solution...

  17. Development of Ribbon Fiber Type Multi-Channel Power Level Monitor with Low-Insertion/Polarization Loss

    Maki; Inai; Akira; Haraguchi; Takeo; Komiya; Kiyotaka; Murashima; Takashi; Sasaki; Kazuhito; Saitoh

    2003-01-01

    We would like to propose a new in-line multi-channel power level monitor, which is applicable as tap-monitor for multi-channel WDM signals. Its ribbon fiber structure has far exceeded PLC performance and realized compact-size and lower insertion/polarization dependent loss.

  18. INFORMATION-MEASURING SYSTEM FOR EVALUATION OF ELECTROMAGNETIC RADIATION POWER LEVELS INFLUENCE TO ITS WEAKENED BY PROTECTIVE SHIELDS

    O. V. Boiprav

    2013-01-01

    Full Text Available An information-measuring system and realized on the basis of its methodology used for evaluation of electromagnetic radiation power levels passing via the protective shielding construction are described. It’s proposed to use the developed methodology for the testing of electromagnetic radiation shields for anechoic chambers

  19. A survey of low-level radioactive waste treatment methods and problem areas associated with commercial nuclear power plants

    Jolley, R.L.; Rodgers, B.R.

    1987-01-01

    A survey was made (June 1985) of technologies that were currently being used, those that had been discontinued, and those that were under consideration for treatment of low-level radioactive waste from the commercial nuclear power plants in the United States. The survey results included information concerning problems areas, areas needing research and development, and the use of mobile treatment facilities.

  20. Effect of Auricular Acupuncture with Low Power Laser on Four Chronic Allergic Dermatoses and Serum IgE Level

    You-hong Hou; Fang Xu; Shao-xi Wu

    2005-01-01

    @@ The objective of the study was to investigate the effectiveness of low power laser irradiating auricular points on four chronic allergic dermatoses including eczema, urticaria, facial cosmetic dermatitis, and atopic dermatitis, and on the changes of serum IgE level.

  1. Wearable Sensor System Powered by a Biofuel Cell for Detection of Lactate Levels in Sweat.

    Garcia, S O; Ulyanova, Y V; Figueroa-Teran, R; Bhatt, K H; Singhal, S; Atanassov, P

    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.

  2. Integrated Solar Power Converters: Wafer-Level Sub-Module Integrated DC/DC Converter

    None

    2012-02-09

    Solar ADEPT Project: CU-Boulder is developing advanced power conversion components that can be integrated into individual solar panels to improve energy yields. The solar energy that is absorbed and collected by a solar panel is converted into useable energy for the grid through an electronic component called an inverter. Many large, conventional solar energy systems use one, central inverter to convert energy. CU-Boulder is integrating smaller, microinverters into individual solar panels to improve the efficiency of energy collection. The University’s microinverters rely on electrical components that direct energy at high speeds and ensure that minimal energy is lost during the conversion process—improving the overall efficiency of the power conversion process. CU-Boulder is designing its power conversion devices for use on any type of solar panel.

  3. Drivers for the Value of Demand Response under Increased Levels of Wind and Solar Power; NREL (National Renewable Energy Laboratory)

    Hale, Elaine

    2015-07-30

    Demand response may be a valuable flexible resource for low-carbon electric power grids. However, there are as many types of possible demand response as there are ways to use electricity, making demand response difficult to study at scale in realistic settings. This talk reviews our state of knowledge regarding the potential value of demand response in several example systems as a function of increasing levels of wind and solar power, sometimes drawing on the analogy between demand response and storage. Overall, we find demand response to be promising, but its potential value is very system dependent. Furthermore, demand response, like storage, can easily saturate ancillary service markets.

  4. Symbol-Level Precoding with Per-antenna Power Constraints for the Multi-beam Satellite Downlink

    Spano, Danilo; Chatzinotas, Symeon; Krause, Jens; Ottersten, Björn

    2016-01-01

    This paper tackles the problem of multi-user interference in the forward downlink channel of a multi-beam satellite system. A symbol-level precoding scheme is considered, where the data information is used, along with the channel state information, in order to exploit the multi-user interference and transform it into useful power at the receiver side. In this framework, the max-min fair problem for constructive interference is formulated and solved, under per-antenna power constraints. The co...

  5. Impact of high level penetration of Wind Turbines on Power System Transient Stability

    Kalogiannis, Theodoros; Llano, Enrique Muller; Hoseinzadeh, Bakhtyar

    2015-01-01

    generators differ from the conventional ones in their inertial contribution to the grid, therefore, in most cases the ability of the system to maintain a stable operation is declined. To investigate this, two standard models are designed in PowerFactory software. The first is used to characterize system...

  6. Modelling of the Multi-Level STATCOM for Harmonic Stability Studies in Offshore Wind Power Plants

    Glasdam, Jakob Bærholm; Bak, Claus Leth; Hjerrild, Jesper;

    2017-01-01

    -bridge MMCC. A comparison with field measurement shows that the proposed model is highly capable to simulate the waveforms of a commercial MMCC, even when a generic controller is applied in the model. Presentedsimulation studiesshowthe occurance of harmonic instability in wind power plants and the application...

  7. Water Use in the US Electric Power Sector: Energy Systems Level Perspectives

    This presentation reviews the water demands of long-range electricity scenarios. It addresses questions such as: What are the aggregate water requirements of the U.S. electric power sector? How could water requirements evolve under different long-range regional generation mixes? ...

  8. MS2 virus inactivation by atmospheric-pressure cold plasma using different gas carriers and power levels.

    Wu, Yan; Liang, Yongdong; Wei, Kai; Li, Wei; Yao, Maosheng; Zhang, Jue; Grinshpun, Sergey A

    2015-02-01

    In this study, airborne MS2 bacteriophages were exposed for subsecond time intervals to atmospheric-pressure cold plasma (APCP) produced using different power levels (20, 24, and 28 W) and gas carriers (ambient air, Ar-O2 [2%, vol/vol], and He-O2 [2%, vol/vol]). In addition, waterborne MS2 viruses were directly subjected to the APCP treatment for up to 3 min. MS2 viruses with and without the APCP exposure were examined by scanning electron microscopy (SEM), reverse transcription-PCR (RT-PCR), and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Viral inactivation was shown to exhibit linear relationships with the APCP generation power and exposure time (R(2) > 0.95 for all energy levels tested) up to 95% inactivation (1.3-log reduction) after a subsecond airborne exposure at 28 W; about the same inactivation level was achieved for waterborne viruses with an exposure time of less than 1 min. A larger amount of reactive oxygen species (ROS), such as atomic oxygen, in APCP was detected for a higher generation power with Ar-O2 and He-O2 gas carriers. SEM images, SDS-PAGE, and agarose gel analysis of exposed waterborne viruses showed various levels of damage to both surface proteins and their related RNA genes after the APCP exposure, thus leading to the loss of their viability and infectivity.

  9. Low-power chip-level optical interconnects based on bulk-silicon single-chip photonic transceivers

    Kim, Gyungock; Park, Hyundai; Joo, Jiho; Jang, Ki-Seok; Kwack, Myung-Joon; Kim, Sanghoon; Kim, In Gyoo; Kim, Sun Ae; Oh, Jin Hyuk; Park, Jaegyu; Kim, Sanggi

    2016-03-01

    We present new scheme for chip-level photonic I/Os, based on monolithically integrated vertical photonic devices on bulk silicon, which increases the integration level of PICs to a complete photonic transceiver (TRx) including chip-level light source. A prototype of the single-chip photonic TRx based on a bulk silicon substrate demonstrated 20 Gb/s low power chip-level optical interconnects between fabricated chips, proving that this scheme can offer compact low-cost chip-level I/O solutions and have a significant impact on practical electronic-photonic integration in high performance computers (HPC), cpu-memory interface, 3D-IC, and LAN/SAN/data-center and network applications.

  10. Relative blood flow changes measured using calibrated frequency-weighted Doppler power at different hematocrit levels.

    Wallace, Sean; Logallo, Nicola; Faiz, Kashif W; Lund, Christian; Brucher, Rainer; Russell, David

    2014-04-01

    In theory, the power of a trans-cranial Doppler signal may be used to measure changes in blood flow and vessel diameter in addition to velocity. In this study, a flow index (FI) of relative changes in blood flow was derived from frequency-weighted Doppler power signals. The FI, plotted against velocity, was calibrated to the zero intercept with absent flow to reduce the effects of non-uniform vessel insonation. An area index was also calculated. FIs were compared with actual flow in four silicone tubes of different diameter at increasing flow rates and increasing hematocrit (Hct) in a closed-loop phantom model. FI values were strongly correlated with actual flow, at constant Hct, but varied substantially with changes in Hct. Percentage changes in area indexes, relative to the 4-mm tube, were strongly correlated with tube cross-sectional area. The implications of these results for in vivo use are discussed.

  11. A low power level-crossing ADC for wearable wireless ECG sensors.

    Zhenzhen Tian; Rendong Ying; Peilin Liu; Guoxing Wang; Yong Lian

    2016-08-01

    Ultra-low power consumption is desired in most wearable biomedical devices. The event-driven based Analog-to-Digital converter (ADC) could be an excellent candidate for low power system because of the reduction in sampling points for biosignals. In the existing event-driven based ADC architectures, two or more high precision comparators are utilized to sample the input signal. In this paper, we propose a new scheme utilizing only one high precision comparator to genertate samples with the assistance of a low precision one. From the Matlab simulations on real ECG signal, it is shown that around 25% reduction on the number of samples can be be achieved compared with the Nyquist sampling scheme.

  12. A low-power and small-area column-level ADC for high frame-rate CMOS pixel sensor

    Zhang, L., E-mail: liang.zhang@iphc.cnrs.fr [School of Physics, Key Laboratory of Particle Physics and Particle Irradiation, Shandong University, 250100 Jinan (China); Institut Pluridisciplinaire Hubert Curien, University of Strasbourg, CNRS/IN2P3/UDS, 23 rue du loess, BP 28, 67037 Strasbourg (France); Morel, F.; Hu-Guo, C.; Hu, Y. [Institut Pluridisciplinaire Hubert Curien, University of Strasbourg, CNRS/IN2P3/UDS, 23 rue du loess, BP 28, 67037 Strasbourg (France)

    2014-07-01

    CMOS pixel sensors (CPS) have demonstrated performances meeting the specifications of the International Linear Collider (ILC) vertex detector (VTX). This paper presents a low-power and small-area 4-bit column-level analog-to-digital converter (ADC) for CMOS pixel sensors. The ADC employs a self-timed trigger and completes the conversion by performing a multi-bit/step approximation. As in the outer layers of the ILC vertex detector hit density is of the order of a few per thousand, in order to reduce power consumption, the ADC is designed to work in two modes: active mode and idle mode. The ADC is fabricated in a 0.35 μm CMOS process with a pixel pitch of 35 μm. It is implemented with 48 columns in a sensor prototype. Each column ADC covers an area of 35 ×545 μm{sup 2}. The measured temporal noise and Fixed Pattern Noise (FPN) are 0.96 mV and 0.40 mV, respectively. The power consumption, for a 3 V supply and 6.25 MS/s sampling rate, is 486 μW during idle time, which is by far the most frequently employed one. This value rises to 714 μW in the case of the active mode. The measured differential nonlinearity (DNL) and integral nonlinearity (INL) are 0.49/−0.28 LSB and 0.29/−0.20 LSB, respectively. - Highlights: • CMOS sensor integrated with column-level ADC is proposed for ILC VTX outer layers. • A low-power and small-area column-level ADC for high frame-rate CPS is presented. • The test results demonstrate the power and area efficiency. • The architecture is suitable for the outer layer CMOS sensors.

  13. Saturated Adaptive Output-Feedback Power-Level Control for Modular High Temperature Gas-Cooled Reactors

    Zhe Dong

    2014-11-01

    Full Text Available Small modular reactors (SMRs are those nuclear fission reactors with electrical output powers of less than 300 MWe. Due to its inherent safety features, the modular high temperature gas-cooled reactor (MHTGR has been seen as one of the best candidates for building SMR-based nuclear plants with high safety-level and economical competitive power. Power-level control is crucial in providing grid-appropriation for all types of SMRs. Usually, there exists nonlinearity, parameter uncertainty and control input saturation in the SMR-based plant dynamics. Motivated by this, a novel saturated adaptive output-feedback power-level control of the MHTGR is proposed in this paper. This newly-built control law has the virtues of having relatively neat form, of being strong adaptive to parameter uncertainty and of being able to compensate control input saturation, which are given by constructing Lyapunov functions based upon the shifted-ectropies of neutron kinetics and reactor thermal-hydraulics, giving an online tuning algorithm for the controller parameters and proposing a control input saturation compensator respectively. It is proved theoretically that input-to-state stability (ISS can be guaranteed for the corresponding closed-loop system. In order to verify the theoretical results, this new control strategy is then applied to the large-range power maneuvering control for the MHTGR of the HTR-PM plant. Numerical simulation results show not only the relationship between regulating performance and control input saturation bound but also the feasibility of applying this saturated adaptive control law practically.

  14. Obesity is not associated with increased knee joint torque and power during level walking.

    DeVita, Paul; Hortobágyi, Tibor

    2003-09-01

    While it is widely speculated that obesity causes increased loads on the knee leading to joint degeneration, this concept is untested. The purpose of the study was to identify the effects of obesity on lower extremity joint kinetics and energetics during walking. Twenty-one obese adults were tested at self-selected (1.29m/s) and standard speeds (1.50m/s) and 18 lean adults were tested at the standard speed. Motion analysis and force platform data were combined to calculate joint torques and powers during the stance phase of walking. Obese participants were more erect with 12% less knee flexion and 11% more ankle plantarflexion in self-selected compared to standard speeds (both pKnee and ankle torques were 17% and 11% higher (pknee work and positive ankle work were 68% and 11% higher (ppowers were statistically identical at the hip and knee but were 88% and 61% higher (both pknee torque and power at their self-selected walking speed and equal knee torque and power while walking at the same speed as lean individuals. We propose that the ability to reorganize neuromuscular function during gait may enable some obese individuals to maintain skeletal health of the knee joint and this ability may also be a more accurate risk indicator for knee osteoarthritis than body weight.

  15. The level of residual dispersion variation and the power of differential expression tests for RNA-Seq data.

    Gu Mi

    Full Text Available RNA-Sequencing (RNA-Seq has been widely adopted for quantifying gene expression changes in comparative transcriptome analysis. For detecting differentially expressed genes, a variety of statistical methods based on the negative binomial (NB distribution have been proposed. These methods differ in the ways they handle the NB nuisance parameters (i.e., the dispersion parameters associated with each gene to save power, such as by using a dispersion model to exploit an apparent relationship between the dispersion parameter and the NB mean. Presumably, dispersion models with fewer parameters will result in greater power if the models are correct, but will produce misleading conclusions if not. This paper investigates this power and robustness trade-off by assessing rates of identifying true differential expression using the various methods under realistic assumptions about NB dispersion parameters. Our results indicate that the relative performances of the different methods are closely related to the level of dispersion variation unexplained by the dispersion model. We propose a simple statistic to quantify the level of residual dispersion variation from a fitted dispersion model and show that the magnitude of this statistic gives hints about whether and how much we can gain statistical power by a dispersion-modeling approach.

  16. The level of residual dispersion variation and the power of differential expression tests for RNA-Seq data.

    Mi, Gu; Di, Yanming

    2015-01-01

    RNA-Sequencing (RNA-Seq) has been widely adopted for quantifying gene expression changes in comparative transcriptome analysis. For detecting differentially expressed genes, a variety of statistical methods based on the negative binomial (NB) distribution have been proposed. These methods differ in the ways they handle the NB nuisance parameters (i.e., the dispersion parameters associated with each gene) to save power, such as by using a dispersion model to exploit an apparent relationship between the dispersion parameter and the NB mean. Presumably, dispersion models with fewer parameters will result in greater power if the models are correct, but will produce misleading conclusions if not. This paper investigates this power and robustness trade-off by assessing rates of identifying true differential expression using the various methods under realistic assumptions about NB dispersion parameters. Our results indicate that the relative performances of the different methods are closely related to the level of dispersion variation unexplained by the dispersion model. We propose a simple statistic to quantify the level of residual dispersion variation from a fitted dispersion model and show that the magnitude of this statistic gives hints about whether and how much we can gain statistical power by a dispersion-modeling approach.

  17. Optical remote sensing and correlation of office equipment functional state and stress levels via power quality disturbances inefficiencies

    Sternberg, Oren; Bednarski, Valerie R.; Perez, Israel; Wheeland, Sara; Rockway, John D.

    2016-09-01

    Non-invasive optical techniques pertaining to the remote sensing of power quality disturbances (PQD) are part of an emerging technology field typically dominated by radio frequency (RF) and invasive-based techniques. Algorithms and methods to analyze and address PQD such as probabilistic neural networks and fully informed particle swarms have been explored in industry and academia. Such methods are tuned to work with RF equipment and electronics in existing power grids. As both commercial and defense assets are heavily power-dependent, understanding electrical transients and failure events using non-invasive detection techniques is crucial. In this paper we correlate power quality empirical models to the observed optical response. We also empirically demonstrate a first-order approach to map household, office and commercial equipment PQD to user functions and stress levels. We employ a physics-based image and signal processing approach, which demonstrates measured non-invasive (remote sensing) techniques to detect and map the base frequency associated with the power source to the various PQD on a calibrated source.

  18. Power System Reliability Evaluation in Wind Power Leveling Load%风电拉平负荷下的发电系统可靠性评估

    吴政球; 唐民富; 张旭乐; 王韬

    2011-01-01

    Abstract: The wind energy always affects the reliability of power system for its randomness , intermittent and Fluctuation. A concept that Wind Power leveling Load(WPLL) is proposed to evaluate the reliability of power system when wind farms are grid - connected. Based on the fact that the wind power and loads are independent random variables, a combined probability distribution function of wind power and loads is deduced by the margin table method. And hence WPLL model is established. This established model is combined with the conventional generator outage capacity model to calculate the reliability indexes, which provides a novel method for the wind power system reliability assessment. Finally, the validity of the proposed model and algorithm is proved by an analysis of the selected sample system. Finally, analysis of the selected sample system illustrates the validity of proposed model and algorithm.%风能具有随机性、间歇性和波动性的特点,风力发电并网对发电系统的可靠性有一定影响,为了评估合风电场的发电系统可靠性,提出了风电功率拉平负荷的概念.基于风电功率与系统负荷为相互独立的随机变量的特点,采用裕度表的方式推导出风电场输出功率跟负荷的联合概率分布,建立了风电功率拉平负荷模型,与常规发电机组停运容量模型结合计算发电系统的可靠性指标,为含风电场的发电系统可靠性分析提供了新的思路和方法.算例计算分析结果表明了该方法的合理性和有效性.

  19. Staff nurses' perceptions of job empowerment and level of burnout: a test of Kanter's theory of structural power in organizations.

    Hatcher, S; Laschinger, H K

    1996-01-01

    Kanter's structural theory of organizational behavior was used as framework to explore the relationship between perceptions of power and opportunity and level of burnout in a sample of 87 hospital staff nurses. Data were collected using a modified version of the Conditions for Work Effectiveness Questionnaire (Chandler, 1986) and the Human Services Survey (Maslach & Jackson, 1986). Consistent with Kanter's theory, perceived access to power and opportunity was significantly related to the three aspects of burnout: level of emotional exhaustion and depersonalization (r = -.3419, p = .004; r = -.2931, p = .02), and personal accomplishments (r = .3630, p = .002). The results of this study are useful for nurse administrators positioned to create organizational structures than empower staff nurses and subsequently decrease burnout.

  20. PSCAD modeling of a two-level space vector pulse width modulation algorithm for power electronics education

    Ahmet Mete Vural

    2016-09-01

    Full Text Available This paper presents the design details of a two-level space vector pulse width modulation algorithm in PSCAD that is able to generate pulses for three-phase two-level DC/AC converters with two different switching patterns. The presented FORTRAN code is generic and can be easily modified to meet many other kinds of space vector modulation strategies. The code is also editable for hardware programming. The new component is tested and verified by comparing its output as six gating signals with those of a similar component in MATLAB library. Moreover the component is used to generate digital signals for closed-loop control of STATCOM for reactive power compensation in PSCAD. This add-on can be an effective tool to give students better understanding of the space vector modulation algorithm for different control tasks in power electronics area, and can motivate them for learning.

  1. Comparison of anthropometry, upper-body strength, and lower-body power characteristics in different levels of Australian football players.

    Bilsborough, Johann C; Greenway, Kate G; Opar, David A; Livingstone, Steuart G; Cordy, Justin T; Bird, Stephen R; Coutts, Aaron J

    2015-03-01

    The aim of this study was to compare the anthropometry, upper-body strength, and lower-body power characteristics in elite junior, sub-elite senior, and elite senior Australian Football (AF) players. Nineteen experienced elite senior (≥4 years Australian Football League [AFL] experience), 27 inexperienced elite senior (Football players' FFSTM are different between playing levels, which are likely because of training and partly explain the observed differences in performance between playing levels highlighting the importance of optimizing FFSTM in young players.

  2. Algorithmic level power and energy optimization for DSP applications: SoftExplorer

    2004-01-01

    We present SoftExplorer, a tool to estimate the power and energy consumption of an algorithm directly from the C program. Four models of processor are available, from the simple RISC ARM7 to the very complex VLIW DSP TIC67. Important phenomena are taken into account, like cache misses, pipeline stalls, and internal / external memory accesses. We show how to use SoftExplorer to find the best data mapping for a DSP application, and to choose a processor and its operating frequency for a MPEG-1 ...

  3. Procedure for conducting probabilistic safety assessment: level 1 full power internal event analysis

    Jung, Won Dae; Lee, Y. H.; Hwang, M. J. [and others

    2003-07-01

    This report provides guidance on conducting a Level I PSA for internal events in NPPs, which is based on the method and procedure that was used in the PSA for the design of Korea Standard Nuclear Plants (KSNPs). Level I PSA is to delineate the accident sequences leading to core damage and to estimate their frequencies. It has been directly used for assessing and modifying the system safety and reliability as a key and base part of PSA. Also, Level I PSA provides insights into design weakness and into ways of preventing core damage, which in most cases is the precursor to accidents leading to major accidents. So Level I PSA has been used as the essential technical bases for risk-informed application in NPPs. The report consists six major procedural steps for Level I PSA; familiarization of plant, initiating event analysis, event tree analysis, system fault tree analysis, reliability data analysis, and accident sequence quantification. The report is intended to assist technical persons performing Level I PSA for NPPs. A particular aim is to promote a standardized framework, terminology and form of documentation for PSAs. On the other hand, this report would be useful for the managers or regulatory persons related to risk-informed regulation, and also for conducting PSA for other industries.

  4. Design considerations regarding slug ruptures in the intermediate power level reactor

    Pearl, W.L.; Pursel, C.A.

    1954-11-01

    The minimum shutdown time, to permit accessibility, for the Intermediate Power Reactor is estimated to be 38 hours. In case the reactor were shutdown following each rupture this long shutdown period would have serious disadvantages. The desirability of being able to make firm power commitments (independent of slug ruptures) has led to a study of the possibility of continuous operation following a rupture. There is evidence to indicate that, at the proposed water temperature, the rate of corrosion of uranium may be so high that at least a major portion of the rupture products may have entered the system before the reactor can be shutdown. A pushout of the affected column would then be a pushout of only those slugs which are still intact and the problem would still remain of removing the rupture products from the system. The first portion of this report is concerned with the rate of corrosion of a slug following rupture and the possible limitations to the principle of non-shutdown operation. These limitations include a flow stoppage by the ruptured can, undue increase in gamma activity, increased corrosion by the rupture products, and adherence of rupture products to the piping. The latter portion of the document is concerned with design considerations of the shielding and water plant so as to eliminate or minimize the effects of the introduction of rupture products into the cooling system. 7 refs., 2 figs.

  5. DC-pass filter design with notch filters superposition for CPW rectenna at low power level

    Rivière, J.; Douyère, A.; Alicalapa, F.; Luk, J.-D. Lan Sun

    2016-03-01

    In this paper the challenging coplanar waveguide direct current (DC) pass filter is designed, analysed, fabricated and measured. As the ground plane and the conductive line are etched on the same plane, this technology allows the connection of series and shunt elements to the active devices without via holes through the substrate. Indeed, this study presents the first step in the optimization of a complete rectenna in coplanar waveguide (CPW) technology: key element of a radio frequency (RF) energy harvesting system. The measurement of the proposed filter shows good performance in the rejection of F0=2.45 GHz and F1=4.9 GHz. Additionally, a harmonic balance (HB) simulation of the complete rectenna is performed and shows a maximum RF-to-DC conversion efficiency of 37% with the studied DC-pass filter for an input power of 10 µW at 2.45 GHz.

  6. Design of Mobile Device Display for Nuclear Power Plant Maintenance Considering the Level of Expertise

    Kim, In; Seong, Poong Hyun [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of)

    2009-10-15

    Maintaining and repairing complex technical facilities such as nuclear power plants requires comprehensive knowledge on a broad range of the system, as well as on operational and safety procedures by the performing maintenance personnel. There exists the need to have access to instruction sheets and parameter tables at the work site. This may not be practicable with printed manuals simply due to their increasing bulk. To cope with this situation, fully mobile wirelessly connected (FMWC) information and communication technologies (ICT) are thought to have high potential for improving field maintenance through increased accessibility and availability of critical information needed in on-site reference or decision making. Among many up-todate technologies, the mobile application to the maintenance support system will be proposed in this paper.

  7. Assessment of electromagnetic field levels from surrounding high-tension overhead power lines for proposed land use.

    Al-Bassam, E; Elumalai, A; Khan, A; Al-Awadi, L

    2016-05-01

    The surrounding outdoor environment for new development has a big effect on the indoor quality of life. The main aim of this work was to determine the suitability of the area for building new schools with reference to electromagnetic field (EMF) effects. The specific objective of this study was to detect the safe distance from the EMF posed by the high-tension overhead power lines in the vicinity of the specified area. The measurements were taken for both the electric and magnetic fields in different months in order to detect the highest EMF levels during the peak power load season. EMDEX II with E-probe and EMDEX II with Linda were used for the measurements. These instruments were all calibrated by ENERTECH Company in USA. The EMF associated with high tension transmission lines that surrounded the proposed site has to be below 0.2 μT (Italian EMF regulations are the most suitable regulations for the establishment of schools in Kuwait). The safety clearance distance from the existing 300-kV high-tension power line has been assigned as 200 m and from other existing 132-kV high-tension power line was 50 m. The proposed site with its predefined boundaries has a magnetic field below the Italian EMF regulations for the establishment of new schools.

  8. Modelling and control of a seven level NPC voltage source inverter. Application to high power induction machine drive

    Gheraia, H.; Berkouk, E.M. [ENP, Alger (Algeria). Lab. de Commande des Processus; Manesse, G. [CNAM-Paris (France). Lab. d' Electricite Industrielle

    2001-08-01

    In this paper, we study a new kind of continuous-alternating converters: a seven-level neutral point clamping (NPC) voltage source inverter (VSI). We propose this inverter for applications in high voltage and high power fields. In the first part, we develop the knowledge and the control models of this inverter using the connections functions of the semi-conductors. After that, we present two pulse width modulation (PWM) algorithms to control this converter using its control model. We propose these algorithms for digital implementation. This multilevel inverter is associated to the induction machine. The performances obtained are full of promise to use it in the high voltage and high power fields of electrical traction. (orig.)

  9. Estimation of radiofrequency power leakage from microwave ovens for dosimetric assessment at nonionizing radiation exposure levels.

    Lopez-Iturri, Peio; de Miguel-Bilbao, Silvia; Aguirre, Erik; Azpilicueta, Leire; Falcone, Francisco; Ramos, Victoria

    2015-01-01

    The electromagnetic field leakage levels of nonionizing radiation from a microwave oven have been estimated within a complex indoor scenario. By employing a hybrid simulation technique, based on coupling full wave simulation with an in-house developed deterministic 3D ray launching code, estimations of the observed electric field values can be obtained for the complete indoor scenario. The microwave oven can be modeled as a time- and frequency-dependent radiating source, in which leakage, basically from the microwave oven door, is propagated along the complete indoor scenario interacting with all of the elements present in it. This method can be of aid in order to assess the impact of such devices on expected exposure levels, allowing adequate minimization strategies such as optimal location to be applied.

  10. Estimation of Radiofrequency Power Leakage from Microwave Ovens for Dosimetric Assessment at Nonionizing Radiation Exposure Levels

    Peio Lopez-Iturri

    2015-01-01

    Full Text Available The electromagnetic field leakage levels of nonionizing radiation from a microwave oven have been estimated within a complex indoor scenario. By employing a hybrid simulation technique, based on coupling full wave simulation with an in-house developed deterministic 3D ray launching code, estimations of the observed electric field values can be obtained for the complete indoor scenario. The microwave oven can be modeled as a time- and frequency-dependent radiating source, in which leakage, basically from the microwave oven door, is propagated along the complete indoor scenario interacting with all of the elements present in it. This method can be of aid in order to assess the impact of such devices on expected exposure levels, allowing adequate minimization strategies such as optimal location to be applied.

  11. Geometrical Optimization for Improved Power Capture of Multi-Level Overtopping Based Wave Energy Converters

    Margheritini, Lucia; Victor, L.; Kofoed, Jens Peter

    2009-01-01

    In multi-level wave energy converters the water from incoming waves is stored in reservoirs one on top of the other. Prevision formula for the overtopping flow rates in the individual reservoirs is fundamental for dimensioning correctly the turbines and optimizing the device. Having a number...... words, the opening between two consecutive reservoirs. 13 different geometries have been tested in 2D irregular waves and a new formulation for prediction of overtopping in multilevel structures is presented....

  12. Electricity consumption by battery-powered consumer electronics: A household-level survey

    McAllister, J. Andrew; Farrell, Alexander E. [Energy and Resources Group, University of California, 310 Barrows Hall, Berkeley, CA 94720-3050 (United States)

    2007-07-15

    The rapid proliferation of battery-powered consumer electronics and their reliance on inefficient linear transformers has been suggested to be an important part of the rapid growth in 'miscellaneous' electricity consumption in recent years, but detailed data are scarce. We conducted a survey of 34 randomly selected households (HHs) in Northern California about the number, type, and usage of consumer electronics. We also measured the energy consumption of 85 typical consumer electronic devices through various parts of the charge cycle. These primary data were supplemented by national sales information for consumer electronics. Results indicate that typical HHs own 8.4 rechargeable devices, which have a total average demand of 12-17 W per HH. Statewide, this amounts to 160-220 MW of demand, with the peak occurring in the late evening, and about 1600 GWh per year. Only about 15% of this energy is used for battery charging, the rest is lost as waste heat during no-load and charge maintenance periods. Technical options to increase the efficiency of these devices, and the research and policy steps needed to realize these savings are discussed. (author)

  13. INFLUENCES OF THE PURCHASING POWER CHANGE ON THE EVOLUTION OF THE AGROALIMETARY MARKETS ON EUROPEAN UNION LEVEL

    Laura Catalina Timiras

    2014-01-01

    Full Text Available This paper aims to identify the manifested connection between the dynamics of the population purchasing power and the dynamic of agroalimentary markets in general as well as by product types on European Union level. Based on the last data supplied by Eurostat 2013, using the specific methods for studying the correlations, we have detected that increases and decreases of the purchasing power generated similar changes on agroalimentary markets level from the point of view of achieved sales in most of the poorer countries of the European Union, but not in those states which got beyond the average gross domestic product per capita of the European Union. This relationship has been noticed only on the agroalimentary markets as a whole (respectively on the amounts spent by the population for purchasing agroalimentary goods, beverages and tobacco, but not on the level of markets of various types of product (“meat and meat products”, “fruit and vegetables”, “dairy produce, eggs and edible oils and fats”, “beverages”, “sugar and chocolate and sugar confectionery”, “tobacco products”.

  14. Assessment of the Current Level of Automation in the Manufacture of Fuel Cell Systems for Combined Heat and Power Applications

    Ulsh, M.; Wheeler, D.; Protopappas, P.

    2011-08-01

    The U.S. Department of Energy (DOE) is interested in supporting manufacturing research and development (R&D) for fuel cell systems in the 10-1,000 kilowatt (kW) power range relevant to stationary and distributed combined heat and power applications, with the intent to reduce manufacturing costs and increase production throughput. To assist in future decision-making, DOE requested that the National Renewable Energy Laboratory (NREL) provide a baseline understanding of the current levels of adoption of automation in manufacturing processes and flow, as well as of continuous processes. NREL identified and visited or interviewed key manufacturers, universities, and laboratories relevant to the study using a standard questionnaire. The questionnaire covered the current level of vertical integration, the importance of quality control developments for automation, the current level of automation and source of automation design, critical balance of plant issues, potential for continuous cell manufacturing, key manufacturing steps or processes that would benefit from DOE support for manufacturing R&D, the potential for cell or stack design changes to support automation, and the relationship between production volume and decisions on automation.

  15. A Lyapunov Stability Theory-Based Control Strategy for Three-Level Shunt Active Power Filter

    Yijia Cao

    2017-01-01

    Full Text Available The three-phase three-wire neutral-point-clamped shunt active power filter (NPC-SAPF, which most adopts classical closed-loop feedback control methods such as proportional-integral (PI, proportional-resonant (PR and repetitive control, can only output 1st–25th harmonic currents with 10–20 kHz switching frequency. The reason for this is that the controller design must make a compromise between system stability and harmonic current compensation ability under the condition of less than 20 kHz switching frequency. To broaden the bandwidth of the compensation current, a Lyapunov stability theory-based control strategy is presented in this paper for NPC-SAPF. The proposed control law is obtained by constructing the switching function on the basis of the mathematical model and the Lyapunov candidate function, which can avoid introducing closed-loop feedback control and keep the system globally asymptotically stable. By means of the proposed method, the NPC-SAPF has compensation ability for the 1st–50th harmonic currents, the total harmonic distortion (THD and each harmonic content of grid currents satisfy the requirements of IEEE Standard 519-2014. In order to verify the superiority of the proposed control strategy, stability conditions of the proposed strategy and the representative PR controllers are compared. The simulation results in MATLAB/Simulink (MathWorks, Natick, MA, USA and the experimental results obtained on a 6.6 kVA NPC-SAPF laboratory prototype validate the proposed control strategy.

  16. Inspections of radiocesium concentration levels in rice from Fukushima Prefecture after the Fukushima Dai-ichi Nuclear Power Plant accident.

    Nihei, Naoto; Tanoi, Keitaro; Nakanishi, Tomoko M

    2015-03-03

    We summarize the inspections of radiocesium concentration levels in rice produced in Fukushima Prefecture, Japan, for 3 years from the nuclear accident in 2011. In 2011, three types of verifications, preliminary survey, main inspection, and emergency survey, revealed that rice with radiocesium concentration levels over 500 Bq/kg (the provisional regulation level until March 2012 in Japan) was identified in the areas north and west of the Fukushima nuclear power plant. The internal exposure of an average adult eating rice grown in the area north of the nuclear plant was estimated as 0.05 mSv/year. In 2012, Fukushima Prefecture authorities decided to investigate the radiocesium concentration levels in all rice using custom-made belt conveyor testers. Notably, rice with radiocesium concentration levels over 100 Bq/kg (the new standard since April 2012 in Japan) were detected in only 71 and 28 bags out of the total 10,338,000 in 2012 and 11,001,000 in 2013, respectively. We considered that there were almost no rice exceeding 100 Bq/kg produced in Fukushima Prefecture after 3 years from the nuclear accident, and the safety of Fukushima's rice were ensured because of the investigation of all rice.

  17. Direct integration of intensity-level data from Affymetrix and Illumina microarrays improves statistical power for robust reanalysis

    Turnbull Arran K

    2012-08-01

    Full Text Available Abstract Background Affymetrix GeneChips and Illumina BeadArrays are the most widely used commercial single channel gene expression microarrays. Public data repositories are an extremely valuable resource, providing array-derived gene expression measurements from many thousands of experiments. Unfortunately many of these studies are underpowered and it is desirable to improve power by combining data from more than one study; we sought to determine whether platform-specific bias precludes direct integration of probe intensity signals for combined reanalysis. Results Using Affymetrix and Illumina data from the microarray quality control project, from our own clinical samples, and from additional publicly available datasets we evaluated several approaches to directly integrate intensity level expression data from the two platforms. After mapping probe sequences to Ensembl genes we demonstrate that, ComBat and cross platform normalisation (XPN, significantly outperform mean-centering and distance-weighted discrimination (DWD in terms of minimising inter-platform variance. In particular we observed that DWD, a popular method used in a number of previous studies, removed systematic bias at the expense of genuine biological variability, potentially reducing legitimate biological differences from integrated datasets. Conclusion Normalised and batch-corrected intensity-level data from Affymetrix and Illumina microarrays can be directly combined to generate biologically meaningful results with improved statistical power for robust, integrated reanalysis.

  18. Gear servicing in the wind power industry; Getriebeservice Windenergie

    NONE

    2005-07-01

    JaKe (Jahnel-Kestermann) is a producer of gears for wind power systems. They offer: Damage analysis anddocumentation; supply of replacement parts; repair and modification of gears; world-wide gear servicing; new gears for own and external products; mobile measuring systems; technological improvements; production of components; toothing, grinding, meshing measurements; production of exchange gears; test performance up to 3 MW; short supply times. (orig.)

  19. A low-power inverter-based CMOS level-crossing analog-to-digital converter for low-frequency biosignal sensing

    Tanaka, Suiki; Niitsu, Kiichi; Nakazato, Kazuo

    2016-03-01

    Low-power analog-to-digital conversion is a key technique for power-limited biomedical applications such as power-limited continuous glucose monitoring. However, a conventional uniform-sampling analog-to-digital converter (ADC) is not suitable for nonuniform biosignals. A level-crossing ADC (LC-ADC) is a promising candidate for low-power biosignal processing because of its event-driven properties. The LC-ADC acquires data by level-crossing sampling. When an input signal crosses the threshold level, the LC-ADC samples the signal. The conventional LC-ADC employs a power-hungry comparator. In this paper, we present a low-power inverter-based LC-ADC. By adjusting the threshold level of the inverter, it can be used as a threshold-fixed window comparator. By using the inverter as an alternative to a comparator, power consumption can be markedly reduced. As a result, the total power consumption is successfully reduced by 90% of that of previous LC-ADC. The inverter-based LC-ADC was found to be very suitable for use in power-limited biomedical devices.

  20. Alpha spectral power and coherence in the patients with mild cognitive impairment during a three-level working memory task

    2007-01-01

    Objective: The functional relationship between calculated alpha band spectral power and inter-/intra-hemispheric coherence during a three-level working memory task of patients with mild cognitive impairment (MCI) was investigated. Methods:Subjects included 35 MCI patients according to the DSM-Ⅳ criteria (mean age: 62.3, SD: 6.5) and 34 healthy controls (mean age:57.4, SD: 4.0) were selected from the community at large. All subjects performed a simple calculation and recall task with three levels of working memory load while electroencephalograph (EEG) signal was recorded. The spectral EEG power was computed over alphal (8.0~10.0 Hz) and alpha2 (10.5~13.0 Hz) frequency bands and was compared between rest stage and working memory processing stage by two-way ANOVA. Post hoc testing analyzed the differences between each two levels of working memory load during task processing. The inter-hemisphere EEG coherence of frontal (F3-F4), central (C3-C4), parietal (P3-P4), temporal (T5-T6) as well as occipital (O1-O2) was compared between MCI patients and normal controls. The EEG signals from F3-C3,F4-C4, C3-P3, C4-P4, P3-O1, P4-O2, T5-C3, T6-C4, T5-P3 and T6-P4 electrode pairs resulted from the intra-hemispheric action for alphal and alpha2 frequency bands. Result: There was significantly higher EEG power from MCI patients than from normal controls both at rest and during working memory processing. Significant differences existed between rest condition and three-level working memory tasks (P<0.001). The inter- and intra-hemispheric coherence during working memory tasks showed a "drop to rise" tendency compared to that at rest condition. There was significantly higher coherence in MCI patients than in the controls.When task difficulties increased, the cortical connectivity of intra-hemispheric diminished while the inter-hemispheric connectivity dominantly maintained the cognitive processing in MCI patients. Conclusion: The results of the present study indicate that the

  1. 风电利用水平评价关键指标研究%Research on Key Indexes Comparison of Wind Power Utilization Level

    白建华; 张钦; 辛颂旭; 谢国辉

    2012-01-01

    为合理评价风电发展状况,以及对风电利用水平进行全面的比较,构建了多元化的风电利用水平指标比较体系.在简要介绍我国风电发展现状的基础上,对国内外风电发展基础条件及风电利用水平进行比较与分析.利用电力系统整体优化规划模型,对未来风电利用水平进行了展望与分析.研究结果表明,科学衡量风电发展水平需从多个方面综合衡量,应重点考虑风电与电力系统协调发展水平;提高电力系统整体规划和运行水平,是最终实现风电科学、高效发展的关键.%In order to reasonably evaluate wind power development status and perform comprehensive comparison of wind power utilization level, the comparison system with various indexes are constructed. Firstly, an overview of the status quo development of wind power in China is briefly introduced, and the basic conditions and utilization level of the development of wind power at home and abroad are clarified. Moreover, with system integrated optimization model, future wind power utilization level comparison is considered. The analytic results show that: wind power utilization level need to be scientifically measured from multiple aspects and the coordination development level between wind power and power system is the key factor. Increasing power system planning and operation level is the key to finally realize wind power scientific and effective development.

  2. Power-law dynamics in an auditory-nerve model can account for neural adaptation to sound-level statistics.

    Zilany, Muhammad S A; Carney, Laurel H

    2010-08-04

    Neurons in the auditory system respond to recent stimulus-level history by adapting their response functions according to the statistics of the stimulus, partially alleviating the so-called "dynamic-range problem." However, the mechanism and source of this adaptation along the auditory pathway remain unknown. Inclusion of power-law dynamics in a phenomenological model of the inner hair cell (IHC)-auditory nerve (AN) synapse successfully explained neural adaptation to sound-level statistics, including the time course of adaptation of the mean firing rate and changes in the dynamic range observed in AN responses. A direct comparison between model responses to a dynamic stimulus and to an "inversely gated" static background suggested that AN dynamic-range adaptation largely results from the adaptation produced by the response history. These results support the hypothesis that the potential mechanism underlying the dynamic-range adaptation observed at the level of the auditory nerve is located peripheral to the spike generation mechanism and central to the IHC receptor potential.

  3. An Approach for the Cooperative Control of FES With a Powered Exoskeleton During Level Walking for Persons With Paraplegia.

    Ha, Kevin H; Murray, Spencer A; Goldfarb, Michael

    2016-04-01

    This paper describes a hybrid system that combines a powered lower limb exoskeleton with functional electrical stimulation (FES) for gait restoration in persons with paraplegia. The general control structure consists of two control loops: a motor control loop, which utilizes joint angle feedback control to control the output of the joint motor to track the desired joint trajectories, and a muscle control loop, which utilizes joint torque profiles from previous steps to shape the muscle stimulation profile for the subsequent step in order to minimize the motor torque contribution required for joint angle trajectory tracking. The implementation described here incorporates stimulation of the hamstrings and quadriceps muscles, such that the hip joints are actuated by the combination of hip motors and the hamstrings, and the knee joints are actuated by the combination of knee motors and the quadriceps. In order to demonstrate efficacy, the control approach was implemented on three paraplegic subjects with motor complete spinal cord injuries ranging from levels T6 to T10. Experimental data indicates that the cooperative control system provided consistent and repeatable gait motions and reduced the torque and power output required from the hip and knee motors of the exoskeleton compared to walking without FES.

  4. Determination of {sup 93}Zr in medium and low level radioactive wastes from Brazilian nuclear power plants

    Oliveira, Thiago C.; Oliveira, Arno H., E-mail: oliveiratco2010@gmail.com, E-mail: heeren@nuclear.ufmg.br [Universidade Federal de Minas Gerais (DEN/UFMG), Belo Horizonte, MG (Brazil). Departamento de Engenharia Nuclear; Kastner, Geraldo F.; Monteiro, Roberto Pellacani G., E-mail: rpgm@cdtn.br, E-mail: gfk@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2015-07-01

    The majority of long-lived radionuclides produced in the nuclear power plants can be regarded as difficult-to-measure radionuclides (RDM), hence chemical separation is necessary before the nuclear measurement of them. The zirconium isotope {sup 93}Zr is a long-lived pure β-particle-emitting radionuclide produced from {sup 235}U fission and from neutron activation of the stable isotope {sup 92}Zr and thus occurring as one of the radionuclides found in nuclear reactors. Due to its long half-life, {sup 93}Zr is one of the radionuclides of interest for the performance of assessment studies of waste storage or disposal. Two different methodologies based on extractive resins and LSC and ICP-MS techniques that enables the {sup 93}Zr determination in medium (ILW) and low level (LLW) radioactive wastes samples from Brazilian nuclear power plants has been developed in our laboratory. Analyzing real samples 65% and 75% chemical yields for {sup 93}Zr recovery were achieved for ICP-MS and LSC techniques, respectively. The detection limits were 0.045 μg.L{sup -1} for ICP-MS and 0.05 Bq.L{sup -1} for LSC techniques. (author)

  5. National-level infrastructure and economic effects of switchgrass cofiring with coal in existing power plants for carbon mitigation.

    Morrow, William R; Griffin, W Michael; Matthews, H Scott

    2008-05-15

    We update a previously presented Linear Programming (LP) methodology for estimating state level costs for reducing CO2 emissions from existing coal-fired power plants by cofiring switchgrass, a biomass energy crop, and coal. This paper presents national level results of applying the methodology to the entire portion of the United States in which switchgrass could be grown without irrigation. We present incremental switchgrass and coal cofiring carbon cost of mitigation curves along with a presentation of regionally specific cofiring economics and policy issues. The results show that cofiring 189 million dry short tons of switchgrass with coal in the existing U.S. coal-fired electricity generation fleet can mitigate approximately 256 million short tons of carbon-dioxide (CO2) per year, representing a 9% reduction of 2005 electricity sector CO2 emissions. Total marginal costs, including capital, labor, feedstock, and transportation, range from $20 to $86/ton CO2 mitigated,with average costs ranging from $20 to $45/ton. If some existing power plants upgrade to boilers designed for combusting switchgrass, an additional 54 million tons of switchgrass can be cofired. In this case, total marginal costs range from $26 to $100/ton CO2 mitigated, with average costs ranging from $20 to $60/ton. Costs for states east of the Mississippi River are largely unaffected by boiler replacement; Atlantic seaboard states represent the lowest cofiring cost of carbon mitigation. The central plains states west of the Mississippi River are most affected by the boiler replacement option and, in general, go from one of the lowest cofiring cost of carbon mitigation regions to the highest. We explain the variation in transportation expenses and highlight regional cost of mitigation variations as transportation overwhelms other cofiring costs.

  6. Predictive Current Control of a 7-level AC-DC back-to-back Converter for Universal and Flexible Power Management System

    Bifaretti, Steffano; Zanchetta, Pericle; Iov, Florin

    2008-01-01

    The paper proposes a novel power conversion system for Universal and Flexible Power Management (UNIFLEX-PM) in Future Electricity Network. Its structure is based on a back-to-back three-phase AC-DC 7-level converter; each AC side is connected to a different PCC, representing the main grid and....../or various distributed generation systems. Effective and accurate power flow control is demonstrated through simulation in Matlab- Simulink environment on a model based on a two-port structure and using a Predictive Control technique. Control of different Power flow profiles has been successfully tested...

  7. Improved sampling and analytical techniques for characterization of very-low-level radwaste materials from commercial nuclear power stations

    Robertson, D.E. [Pacific Northwest Labs., Richland, WA (United States); Robinson, P.J. [Electric Power Research Inst., Palo Alto, CA (United States)

    1989-11-01

    This paper summarizes the unique sampling methods that were utilized in a recently completed project sponsored by the Electric Power Research Institute (EPRI) to perform accurate and precise radiological characterizations of several very-low-level radwaste materials from commercial nuclear power stations. The waste types characterized during this project included dry active waste (DAW), oil, secondary-side ion exchange resin, and soil. Special precautions were taken to insure representative sampling of the DAW. This involved the initial direct, quantitative gamma spectrometric analyses of bulk quantities (208-liter drums) of DAW utilizing a specially constructed barrel scanner employing a collimated intrinsic germanium detector assembly. Subsamples of the DAW for destructive radiochemical analyses of the difficult-to-measure 10CF61 radionuclides were then selected which had the same isotopic composition (to within {+-}25%) as that measured for the entire drum of DAW. The techniques for accomplishing this sampling are described. Oil samples were collected from the top, middle and bottom sections of 208-liter drums for radiochemical analyses. These samples were composited to represent the entire drum of oil. The accuracy of this type of sampling was evaluated by comparisons with direct, quantitative assays of a number of the drums using the barrel scanning gamma-ray spectrometer. The accuracy of sampling drums of spent secondary-side ion exchange resin was evaluated by comparing the radionuclide contents of grab samples taken from the tops of the drums with direct assays performed with the barrel scanner. The results of these sampling evaluations indicated that the sampling methods used were generally adequate for providing a reasonably representative subsample from bulk quantities of DAW, oil, and resin. The study also identified a number of potential pitfalls, in sampling of these materials.

  8. THE RELATIONSHIP BETWEEN AEROBIC POWER AND REPEATED SPRINT ABILITY IN YOUNG SOCCER PLAYERS WITH DIFFERENT LEVELS OF VO2 MAX

    Rostam Alizadeh

    2010-06-01

    Full Text Available In some team sports such as soccer which is interval, athletes need to prepare themselves immediatelyfor the next activity. Therefore it is very important to have enough information on characteristics of recovery phase and quick recovery to the first situation and to have the minimum speed reduction. The purpose of this study was to determine the relationship between aerobic power and repeated sprint ability (RSA or decrementindex in young soccer players in three different levels of Vo2max. Methods: For this reason 41 volunteers were divided in to three groups with different levels of Vo2max ml.kg-1.min-1 low 37.22 ± 2.3 (n= 18, age 17.1 ± 0.9 year, height 170.6 ± 0.76 cm, weight 67.1 ± 5.05 kg medium 46.46± 1.97 ml.kg-1.min-1 (n= 13, age 17.6± 0.76year, height 173.8 ± 4.84 cm, weight 65.9 ± 4.92 kg and high 55.63 ± 1.52 ml.kg-1.min-1 (n=10, age 17.4 ±0.69 year, height 177 ± 3.23 cm, weight 71.4 ± 3.94 kg. To determine Vo2max a graded exercise test until volitional exhaustion on treadmill was used, and also RAST was used to measure RSA. The lactate accumulation was measured before and after RSA protocol. Pearson's correlation was used to determine the correlation between the aerobic power and RSA. The results indicated that there are significant relationship between Vo2max anddecremental index in low Vo2max group (r= 0.86, p= 0.001, no significant relationship medium Vo2max group (r= 0.14, p= 0.63 and negative significant relationship in high Vo2max group (r= - 0.64, p= 0.04. There are no significant relationship between Lactate accumulation and decremental index in medium (r= 0.005, p= 0.98 and high Vo2max groups (r=0.27, p= 0.45. Discussion: It is possible that the recovery of inter muscular resources relates to aerobic ability, but there are other factors effective in RSA rather than Vo2max and Lactate accumulation. The current study showed a normal curved relationship between Vo2max and RSA.

  9. Iso standardization of theoretical activity evaluation method for low and intermediate level activated waste generated at nuclear power plants

    Makoto Kashiwagi [JGC, Yokohama, 220-6001 (Japan); Garamszeghy, Mike [NWMO, Toronto, Ontario, M4T 2S3 (Canada); Lantes, Bertrand; Bonne, Sebastien [EDF UTO, 93192 Noisy le Grand (France); Pillette-Cousin, Lucien [AREVA TA, 91192 Gif-sur-Yvette (France); Leganes, Jose Luis [ENRESA, 28043 Madrid (Spain); Volmert, Ben [NAGRA, CH-5430 Wettingen (Switzerland); James, David W. [DW James Consulting, North Oaks, MN 55127 (United States)

    2013-07-01

    Disposal of low-and intermediate-level activated waste generated at nuclear power plants is being planned or carried out in many countries. The radioactivity concentrations and/or total quantities of long-lived, difficult-to-measure nuclides (DTM nuclides), such as C-14, Ni-63, Nb-94, α emitting nuclides etc., are often restricted by the safety case for a final repository as determined by each country's safety regulations, and these concentrations or amounts are required to be known and declared. With respect to waste contaminated by contact with process water, the Scaling Factor method (SF method), which is empirically based on sampling and analysis data, has been applied as an important method for determining concentrations of DTM nuclides. This method was standardized by the International Organization for Standardization (ISO) and published in 2007 as ISO21238 'Scaling factor method to determine the radioactivity of low and intermediate-level radioactive waste packages generated at nuclear power plants' [1]. However, for activated metal waste with comparatively high concentrations of radioactivity, such as may be found in reactor control rods and internal structures, direct sampling and radiochemical analysis methods to evaluate the DTM nuclides are limited by access to the material and potentially high personnel radiation exposure. In this case, theoretical calculation methods in combination with empirical methods based on remote radiation surveys need to be used to best advantage for determining the disposal inventory of DTM nuclides while minimizing exposure to radiation workers. Pursuant to this objective a standard for the theoretical evaluation of the radioactivity concentration of DTM nuclides in activated waste, is in process through ISO TC85/SC5 (ISO Technical Committee 85: Nuclear energy, nuclear technologies, and radiological protection; Subcommittee 5: Nuclear fuel cycle). The project team for this ISO standard was formed in 2011 and

  10. Wind power in power systems

    Ackermann, Thomas

    2012-01-01

    The second edition of the highly acclaimed Wind Power in Power Systems has been thoroughly revised and expanded to reflect the latest challenges associated with increasing wind power penetration levels. Since its first release, practical experiences with high wind power penetration levels have significantly increased. This book presents an overview of the lessons learned in integrating wind power into power systems and provides an outlook of the relevant issues and solutions to allow even higher wind power penetration levels. This includes the development of standard wind turbine sim

  11. Measures of nonclassicality for a two-level atom interacting with power-law potential field under decoherence effect

    Abdel-Khalek, S.; Berrada, K.; Alkhateeb, Sadah A.

    2016-09-01

    In this paper, we propose a useful quantum system to perform different tasks of quantum information and computational technologies. We explore the required optimal conditions for this system that are feasible with real experimental realization. We present an active way to control the variation of some measures of nonclassicality considering the time-dependent coupling and photon transition effects under a model that closely describes a realistic experimental scenario. We investigate qualitatively the quantum measures for a two-level atom system interacting with a quantum field initially defined in a coherent state in the framework of power-law potentials (PLPCSs). We study the nonlocal correlation in the whole system state using the negativity as a measure of entanglement in terms of the exponent parameter, number of photon transition, and phase damping effect. The influences of the different physical parameters on the statistical properties and purity of the field are also demonstrated during the time evolution. The results indicate that the preservation and enhancement of entanglement greatly benefit from the combination of the choice of the physical parameters. Finally, we explore an interesting relationship between the different quantum measures of non-classicality during the time evolution in the absence and presence of time-dependent coupling effect.

  12. State-level infrastructure and economic effects of switchgrass cofiring with coal in existing power plants for carbon mitigation.

    Morrow, William R; Griffin, W Michael; Matthews, H Scott

    2007-10-01

    This paper presents a linear programming (LP) methodology for estimating the cost of reducing a state's coal-fired power plant carbon dioxide emissions by cofiring switchgrass and coal. LP modeling allows interplay between regionally specific switchgrass production forecasts, coal plant locations, and individual coal plant historic performance data to determine an allocation of switchgrass minimizing cost or maximizing carbon reduction. The LP methodology is applied to two states, Pennsylvania (PA) and Iowa (IA), and results are presented with a discussion of modeling assumptions, techniques, and carbon mitigation policy implications. The LP methodology estimates that, in PA, 4.9 million tons of CO2/year could be mitigated at an average cost of less than $34/ton of CO2 and that, in IA, 7 million tons of CO2/year could be mitigated at an average Cost of Mitigation of $27/ton of CO2. Because the factors determining the cofiring costs vary so much between the two states, results suggest that cofiring costs will also vary considerably between different U.S. regions. A national level analysis could suggest a lowest-cost cofiring region. This paper presents techniques and assumptions that can simplify biomass energy policy analysis with little effect on analysis conclusions.

  13. Laser inertial fusion dry-wall materials response to pulsed ions at power-plant level fluences

    Renk, T. J.; Tanaka, T. J.; Olson, C. L.; Peterson, R. R.; Knowles, T. R.

    2004-08-01

    Pulses of MeV-level ions with fluences of up to 20 J/cm 2 can be expected to impinge on the first-wall of future laser-driven Inertial Fusion Energy (IFE) power plants. To simulate the effect of these ions, we have exposed candidate dry-wall materials to ion pulses from RHEPP-1, located at Sandia National Laboratories. Various forms of tungsten and tungsten alloy were exposed to up to 1000 pulses, with some samples heated to 600 °C. Thresholds for roughening and material removal, and evolution of surface morphology were measured and compared with code predictions for materials response. Tungsten is observed to undergo surface roughening and subsurface crack formation that evolves over hundreds of pulses, and which can occur both below and above the melt threshold. Heating and Re-alloying mitigate, but do not eliminate, these apparently thermomechanically-caused effects. Use of a 3-D geometry, and/or use of the tungsten in thin-film form may offer improved survivability compared to bulk tungsten.

  14. The intermediates take it all: asymptotics of higher criticism statistics and a powerful alternative based on equal local levels.

    Gontscharuk, Veronika; Landwehr, Sandra; Finner, Helmut

    2015-01-01

    The higher criticism (HC) statistic, which can be seen as a normalized version of the famous Kolmogorov-Smirnov statistic, has a long history, dating back to the mid seventies. Originally, HC statistics were used in connection with goodness of fit (GOF) tests but they recently gained some attention in the context of testing the global null hypothesis in high dimensional data. The continuing interest for HC seems to be inspired by a series of nice asymptotic properties related to this statistic. For example, unlike Kolmogorov-Smirnov tests, GOF tests based on the HC statistic are known to be asymptotically sensitive in the moderate tails, hence it is favorably applied for detecting the presence of signals in sparse mixture models. However, some questions around the asymptotic behavior of the HC statistic are still open. We focus on two of them, namely, why a specific intermediate range is crucial for GOF tests based on the HC statistic and why the convergence of the HC distribution to the limiting one is extremely slow. Moreover, the inconsistency in the asymptotic and finite behavior of the HC statistic prompts us to provide a new HC test that has better finite properties than the original HC test while showing the same asymptotics. This test is motivated by the asymptotic behavior of the so-called local levels related to the original HC test. By means of numerical calculations and simulations we show that the new HC test is typically more powerful than the original HC test in normal mixture models.

  15. Near-Field Acoustic Power Level Analysis of F31/A31 Open Rotor Model at Simulated Cruise Conditions, Technical Report II

    Sree, Dave

    2015-01-01

    Near-field acoustic power level analysis of F31A31 open rotor model has been performed to determine its noise characteristics at simulated cruise flight conditions. The non-proprietary parts of the test data obtained from experiments in the 8x6 supersonic wind tunnel were provided by NASA-Glenn Research Center. The tone and broadband components of total noise have been separated from raw test data by using a new data analysis tool. Results in terms of sound pressure levels, acoustic power levels, and their variations with rotor speed, freestream Mach number, and input shaft power, with different blade-pitch setting angles at simulated cruise flight conditions, are presented and discussed. Empirical equations relating models acoustic power level and input shaft power have been developed. The near-field acoustic efficiency of the model at simulated cruise conditions is also determined. It is hoped that the results presented in this work will serve as a database for comparison and improvement of other open rotor blade designs and also for validating open rotor noise prediction codes.

  16. Power Analysis to Detect the Effects of a Continuous Moderator in 2-Level Simple Cluster Random Assignment Experiments

    Dong, Nianbo

    2014-01-01

    For intervention studies involving binary treatment variables, procedures for power analysis have been worked out and computerized estimation tools are generally available. The purpose of this study is to: (1) develop the statistical formulations for calculating statistical power, minimum detectable effect size (MDES) and its confidence interval,…

  17. Experimental analysis of flexibility change with different levels of power reduction by demand response activation on thermostat controlled loads

    Lakshmanan, Venkatachalam; Marinelli, Mattia; Hu, Junjie

    2017-01-01

    This paper studies the flexibility available with thermostatically controlled loads (TCLs) to provide power system services by demand response (DR) activation. Although the DR activation on TCLs can provide power system ancillary services, it is important to know how long such services can...

  18. (14)C levels in the vicinity of the Fukushima Dai-ichi Nuclear Power Plant prior to the 2011 accident.

    Xu, Sheng; Cook, Gordon T; Cresswell, Alan J; Dunbar, Elaine; Freeman, Stewart P H T; Hastie, Helen; Hou, Xiaolin; Jacobsson, Piotr; Naysmith, Philip; Sanderson, David C W; Tripney, Brian G; Yamaguchi, Katsuhiko

    2016-06-01

    A 50-year-old Japanese cedar (Cryptomeria japonica) from Okuma, ∼1 km southwest of the Fukushima Dai-ichi Nuclear Power Plant, was cored and each annual ring was analysed for (14)C. The (14)C specific activity values varied from 330.4 Bq kg(-1) C in the tree ring formed in 1971 to 231.2 Bq kg(-1) C in the 2014 ring. During the periods 1971-1976 and 2011-2014, the (14)C specific activities are indistinguishable from the ambient background values. However, compared with the ambient atmospheric levels, the (14)C specific activities between 1977 and 2010 are significantly elevated, clearly indicating (14)C discharges from the reactors during their normal operations. In addition, the specific activities are positively correlated with the annual electricity generation values. The excess (14)C specific activities were wind direction is east-southeast/southeast with a frequency of ∼30%, in comparison to ∼20% frequency for the direction of the site under study (north-northeast/northeast). This would tend to indicate a similar magnitude of additional effective dose and consequently no significant radiological impact of atmospheric (14)C discharges from the FDNPP during the entire period of normal operations. Additionally, no (14)C pulse in activity can be observed in the year 2011 ring. This might be caused by a limited (14)C release from the damaged reactors during the accident or that the prevailing wind during the short period of release (11th-25th March 2011) was not in the direction of Okuma.

  19. Power Performance Test on a Full-Scale Wind Turbine

    Wangsness, Erik Brevik

    2014-01-01

    There is a standard made by the International Electrotechnical Commission (IEC) for how a power performance test on a full-scale wind turbine should be performed. By using this standard as a guideline, I have performed a power performance test on the 3 MW wind turbine at Valsneset. This was done by measuring the incoming wind towards the wind turbine rotor area with a lidar in conjunction with a cup anemometer at a 33 m high meteorological mast (met-mast). The lidar and cup anemometer measure...

  20. Safety Management of County-level Power Supply Enterprises%县级供电企业安全管理探析

    张曙光

    2013-01-01

      随着农电体制改革的深化,农电事业有了长足发展,农电管理中一些新的矛盾也随之显现出来。安全生产是电力企业永恒的主题。大家知道,作为县级供电企业,抓好安全生产管理工作的重要作用和意义日益凸显,要确保县级供电企业安全生产,必须建设一支“一强三优”县级供电企业队伍,强化安全生产管理,实现县级供电企业管理与网、省公司管理全面融合。安全生产管理抓得好。无论对确保社会稳定和人民生命财产不受损失,还是对县级供电企业本身经济效益和社会效益都具有十分重要作用。%With deepening of reform of rural power system, the rural power enterprises have made remarkable development, some new contradictions in rural power management also unfold. Production safety is the eternal theme in the electric power enterprise. As we all know, as a county-level power supply enterprise, pays special attention to the safety in production important function and meaning of management, to ensure that the county level power supply enterprise safety in production, to build a "one strong three-excellent" county-level power supply enterprise team, strengthening the management of production safety and implementation at the county level power supply enterprises, provincial company management comprehensive integration management and network. Safety production management is a good catch. No matter to ensure social stability and people's life and property from losses, or economic benefit and social benefit of county-level power supply enterprise itself has a very important role.

  1. Load leveling by a battery system in an electric power system with a photovoltaic system; Taiyoko hatsuden system ga donyusareta denryoku keito no chikudenchi ni yoru fuka heijunka

    Kenmoku, Y.; Sakakibara, T. [Toyohashi University of Technology, Aichi (Japan); Nakagawa, S. [Maizuru College of Technology, Kyoto (Japan); Kawamoto, T. [Shizuoka University, Shizuoka (Japan)

    1997-11-25

    Storage battery-aided load leveling system is introduced into a power system having a photovoltaic power generation (PV) system, and the effect of the introduction is examined. For this purpose, the resultant improvement on the load factor and reduction in the annual cost are evaluated. Used as the load factor in the studies are the hourly records of power transmitted and received by Chubu Electric Power Co., Inc., in 1995. The output of the PV system is calculated using weather data collected in Nagoya City in the same year. Findings as the result of the studies are stated below. The maximum power is suppressed but a little if it is only the PV system that is introduced into the system. That is, a 2GW PV system introduced into the system suppresses the maximum power only by 0.5GW or less. The maximum power is suppressed more effectively when a storage battery is added, and it decreases linearly with an increase in the storage battery capacity. As for reduction in the cost, the reducing effect is higher when the rate of storage battery capacity/introduced PV capacity is higher in the presence of an introduced PV capacity of 0.8GW or more. 2 refs., 7 figs., 3 tabs.

  2. The discriminative power of the Interval Shuttle Run Test and the Maximal Multistage Shuttle Run Test for playing level of soccer

    Lemmink, K.A.P.M.; Verheijen, R.; Visscher, C.

    2004-01-01

    AIM: The purpose of this study was to examine the discriminative power of the recently developed Interval Shuttle Run Test (ISRT) and the widely used Maximal Multistage 20 m Shuttle Run Test (MMSRT) for soccer players at different levels of competition. The main difference between the tests is that

  3. Evaluation of the High Power Performance of the Upgraded NSTX HHFW Antenna

    Ryan, P. M.; McLean, A.; Hosea, J. C.; Leblanc, B. P.; Perkins, R. J.; Taylor, G.; Wilson, J. R.; Pinsker, R. I.; the NSTX Team

    2011-10-01

    The end-grounded straps of the NSTX HHFW antenna array were replaced in 2009 with center-grounded straps to reduce the interior voltages and electric fields in the plasma/Faraday shield region. After accumulated lithium deposits were removed from the antenna surface by plasma conditioning, reliable HHFW power was increased to 3-4 MW from the 2-3 MW levels of 2008. However, in 2010 reliable operation was limited to less than 2 MW, primarily due to changes in the antenna environment associated with the Liquid Li Divertor. The antennas have been cleaned of Li coatings and Li2CO3 dust in preparation for the 2011 campaign. The HHFW system will be operated early in the campaign to minimize the effects of Li accumulation in ascertaining the efficacy of reducing internal fields to increase reliability. A visible light camera covering the complete array will observe Li ablation from the powered antenna, and a newly installed IR camera covering ~40% of the array will monitor localized hot spot formation. Work supported by USDOE Contract Nos. DE-AC05-00OR22725 and DE-AC02-09CH11466.

  4. High-power and steady-state operation of ICRF heating in the large helical device

    Mutoh, T., E-mail: mutoh@nifs.ac.jp; Seki, T.; Saito, K.; Kasahara, H.; Seki, R.; Kamio, S.; Kumazawa, R.; Kubo, S.; Shimozuma, T.; Yoshimura, Y.; Igami, H.; Takahashi, H.; Ii, T.; Makino, R.; Nagaoka, K.; Nomura, G. [National Institute for Fusion Science, 322-6, Oroshi-cho, Toki, Gifu, 509-5292 (Japan); Shinya, T. [The University of Tokyo, Kashiwa 2777-8561 (Japan)

    2015-12-10

    Recent progress in an ion cyclotron range of frequencies (ICRF) heating system and experiment results in a Large Helical Device (LHD) are reported. Three kinds of ICRF antenna pairs were installed in the LHD, and the operation power regimes were extended up to 4.5 MW; also, the steady-state operation was extended for more than 45 min in LHD at a MW power level. We studied ICRF heating physics in heliotron configuration using a Hand Shake type (HAS) antenna, Field Aligned Impedance Transforming (FAIT) antenna, and Poloidal Array (PA) antenna, and established the optimum minority-ion heating scenario in an LHD. The FAIT antenna having a novel impedance transformer inside the vacuum chamber could reduce the VSWR and successfully injected a higher power to plasma. We tested the PA antennas completely removing the Faraday-shield pipes to avoid breakdown and to increase the plasma coupling. The heating performance was almost the same as other antennas; however, the heating efficiency was degraded when the gap between the antenna and plasma surface was large. Using these three kinds of antennas, ICRF heating could contribute to raising the plasma beta with the second- and third-harmonic cyclotron heating mode, and also to raising the ion temperature as discharge cleaning tools. In 2014, steady-state operation plasma with a line-averaged electron density of 1.2 × 10{sup 19} m{sup −3}, ion and electron temperature of 2 keV, and plasma sustainment time of 48 min was achieved with ICH and ECH heating power of 1.2 MW for majority helium with minority hydrogen. In 2015, the higher-power steady-state operation with a heating power of up to 3 MW was tested with higher density of 3 × 10{sup 19} m{sup −3}.

  5. The Impact of Wind Development on County-Level Income and Employment: A Review of Methods and an Empirical Analysis (Fact Sheet). Wind And Water Power Program (WWPP).

    Brown, Jason P. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Pender, John [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Wiser, Ryan [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Lantz, Eric [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Hoen, Ben [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2012-09-02

    The economic development potential from wind power installations has been a driver of public and policy support for the industry at the local and state levels for many years. The possibility for economic development has been particularly salient in rural areas of the country where new investment, earnings growth, and employment opportunities have, in many cases, otherwise trended downward for some time. Despite frequent mention of the economic development potential of wind power projects, however, questions persist on the magnitude, distribution, and durability of these impacts. Of particular concern for rural communities is whether new investment in wind power projects stimulates long-term local economic growth and employment. Questions about the economic development and employment impacts of wind power also persist at the national level. However, such debates tend to be more concerned with potential economic losses associated with displacement of other energy sources or land uses and the macroeconomic effects of policy support for renewable energy and changes in electricity rates that might result from wind energy deployment. The present analysis focuses solely on county-level impacts.

  6. Metabolic cost of level-ground walking with a robotic transtibial prosthesis combining push-off power and nonlinear damping behaviors: preliminary results.

    Yanggang Feng; Jinying Zhu; Qining Wang

    2016-08-01

    Recent advances in robotic technology are facilitating the development of robotic prostheses. Our previous studies proposed a lightweight robotic transtibial prosthesis with a damping control strategy. To improve the performance of power assistance, in this paper, we redesign the prosthesis and improve the control strategy by supplying extra push-off power. A male transtibial amputee subject volunteered to participate in the study. Preliminary experimental results show that the proposed prosthesis with push-off control improves energy expenditure by a percentage ranged from 9.72 % to 14.99 % for level-ground walking compared with the one using non-push-off control.

  7. A review of water use in the U.S. electric power sector: insights from systems-level perspectives

    Thermoelectric power production comprised 41% of total freshwater withdrawals in the U.S., surpassing even agriculture. This review highlights scenarios of the electric sector’s future demands for water, including scenarios that limit both CO2 and water availability. A number o...

  8. Levels of {sup 137}Cs and {sup 40}K in marine superficial sediments near the Angra Nuclear Power Plant (Angra dos Reis, SE Brazil)

    Lima Ferreira, Paulo Alves de; Farina Amorim, Lais; Marone Tura, Pedro; Medeiros Zacheo, Valter Andre; Lopes Figueira, Rubens Cesar [Universidade de Sao Paulo (IO-USP), SP (Brazil). Inst. Oceanografico

    2015-07-01

    This study evaluated the spatial distribution of two environmentally relevant radionuclides, {sup 137}Cs and {sup 40}K, in marine superficial sediments around the Angra Nuclear Power Plant, the only Brazilian nuclear power plant complex, thus establishing a baseline for bottom sediments, given the international importance of environmental monitoring around nuclear facilities. It was observed that these radionuclides are mostly present in the muddy sediments as a result of their stronger association with its fine-grained fraction, and that their lowest levels are located around the liquid effluent discharge of the plant, as a consequence of the prevented deposition of fine sediments due to the strong discharge water flux. The comparison of the {sup 137}Cs activities in the region with other locations in the world showed that the presence of this artificial nuclide is due to the atmospheric fallout from past nuclear tests made during the Cold War, not to the nuclear power plant activities.

  9. Duration-tunable picosecond source at 560  nm with watt-level average power.

    Runcorn, T H; Murray, R T; Kelleher, E J R; Popov, S V; Taylor, J R

    2015-07-01

    A pulse source at 560 nm that is tunable in duration between 50 ps and 2.7 ns with >1  W of average power and near diffraction-limited beam quality is demonstrated. The source is based on efficient (up to 50%) second-harmonic generation in a periodically poled lithium tantalate crystal of a linearly polarized fiber-integrated Raman amplifier operating at 1120 nm. A duration-tunable ytterbium master-oscillator power-fiber amplifier is used to pulse-pump the Raman amplifier, which is seeded by a continuous-wave distributed-feedback laser diode at 1120 nm. The performance of the system using two different master oscillator schemes is compared. A pulse energy of up to 765 nJ is achieved with a conversion efficiency of 25% from the ytterbium fiber pump, demonstrating a compact and turn-key architecture for obtaining high peak-power radiation at 560 nm.

  10. 'The one with the purse makes policy': Power, problem definition, framing and maternal health policies and programmes evolution in national level institutionalised policy making processes in Ghana.

    Koduah, Augustina; Agyepong, Irene Akua; van Dijk, Han

    2016-10-01

    This paper seeks to advance our understanding of health policy agenda setting and formulation processes in a lower middle income country, Ghana, by exploring how and why maternal health policies and programmes appeared and evolved on the health sector programme of work agenda between 2002 and 2012. We theorized that the appearance of a policy or programme on the agenda and its fate within the programme of work is predominately influenced by how national level decision makers use their sources of power to define maternal health problems and frame their policy narratives. National level decision makers used their power sources as negotiation tools to frame maternal health issues and design maternal health policies and programmes within the framework of the national health sector programme of work. The power sources identified included legal and structural authority; access to authority by way of political influence; control over and access to resources (mainly financial); access to evidence in the form of health sector performance reviews and demographic health surveys; and knowledge of national plans such as Ghana Poverty Reduction Strategy. Understanding of power sources and their use as negotiation tools in policy development should not be ignored in the pursuit of transformative change and sustained improvement in health systems in low- and middle income countries (LMIC).

  11. The level of air pollution in the impact zone of coal-fired power plant (Karaganda City) using the data of geochemical snow survey (Republic of Kazakhstan)

    Adil'bayeva, T. E.; Talovskaya, A. V.; Yazikov, Ye G.; Matveenko, I. A.

    2016-09-01

    Coal-fired power plants emissions impact the air quality and human health. Of great significance is assessment of solid airborne particles emissions from those plants and distance of their transportation. The article presents the results of air pollution assessment in the zone of coal-fired power plant (Karaganda City) using snow survey. Based on the mass of solid airborne particles deposited in snow, time of their deposition on snow at the distance from 0.5 to 4.5 km a value of dust load has been determined. It is stated that very high level of pollution is observed at the distance from 0.5 to 1 km. there is a trend in decrease of dust burden value with the distance from the stacks of coal-fired power plant that may be conditioned by the particle size and washing out smaller ash particles by ice pellets forming at freezing water vapour in stacks of the coal-fired power plant. Study in composition of solid airborne particles deposited in snow has shown that they mainly contain particulates of underburnt coal, Al-Si- rich spheres, Fe-rich spheres, and coal dust. The content of the particles in samples decreases with the distance from the stacks of the coal-fired power plant.

  12. Power Balance Control in an AC/DC/AC Converter for Regenerative Braking in a Two-Voltage-Level Flywheel-Based Driveline

    Janaína G. Oliveira

    2011-01-01

    Full Text Available The integration of a flywheel as a power handling can increase the energy storage capacity and reduce the number of battery charge/discharge cycles. Furthermore, the ability of recovering energy of the vehicle during breaking can increase the system efficiency. The flywheel-based all-electric driveline investigated here has its novelty in the use of a double-wound flywheel motor/generator, which divides the system in two different voltage levels, enhancing the efficiency of the electric driveline. The connection of two AC electrical machines (i.e., the flywheel and the wheel motor with different and variable operation frequency is challenging. A power matching control applied to an AC/DC/AC converter has been implemented. The AC/DC/AC converter regenerates the electric power converted during braking to the flywheel machine, used here as power handling device. By controlling the power balance, the same hardware can be used for acceleration and braking, providing the reduction of harmonics and robust response. A simulation of the complete system during braking mode has been performed both in Matlab and Simulink, and their results have been compared. The functionality of the proposed control has been shown and discussed, with full regeneration achieved. A round-trip efficiency (wheel to wheel higher than 80% has been obtained.

  13. Improving the power of an efficacy study of a social and emotional learning program: application of generalizability theory to the measurement of classroom-level outcomes.

    Mashburn, Andrew J; Downer, Jason T; Rivers, Susan E; Brackett, Marc A; Martinez, Andres

    2014-04-01

    Social and emotional learning programs are designed to improve the quality of social interactions in schools and classrooms in order to positively affect students' social, emotional, and academic development. The statistical power of group randomized trials to detect effects of social and emotional learning programs and other preventive interventions on setting-level outcomes is influenced by the reliability of the outcome measure. In this paper, we apply generalizability theory to an observational measure of the quality of classroom interactions that is an outcome in a study of the efficacy of a social and emotional learning program called The Recognizing, Understanding, Labeling, Expressing, and Regulating emotions Approach. We estimate multiple sources of error variance in the setting-level outcome and identify observation procedures to use in the efficacy study that most efficiently reduce these sources of error. We then discuss the implications of using different observation procedures on both the statistical power and the monetary costs of conducting the efficacy study.

  14. Evaluation of training programs and entry-level qualifications for nuclear-power-plant control-room personnel based on the systems approach to training

    Haas, P M; Selby, D L; Hanley, M J; Mercer, R T

    1983-09-01

    This report summarizes results of research sponsored by the US Nuclear Regulatory Commission (NRC) Office of Nuclear Regulatory Research to initiate the use of the Systems Approach to Training in the evaluation of training programs and entry level qualifications for nuclear power plant (NPP) personnel. Variables (performance shaping factors) of potential importance to personnel selection and training are identified, and research to more rigorously define an operationally useful taxonomy of those variables is recommended. A high-level model of the Systems Approach to Training for use in the nuclear industry, which could serve as a model for NRC evaluation of industry programs, is presented. The model is consistent with current publically stated NRC policy, with the approach being followed by the Institute for Nuclear Power Operations, and with current training technology. Checklists to be used by NRC evaluators to assess training programs for NPP control-room personnel are proposed which are based on this model.

  15. Evaluation of the Submerged Demineralizer System (SDS) flowsheet for decontamination of high-activity-level water at the Three Mile Island Unit 2 Nuclear Power Station

    Campbell, D. O.; Collins, E. D.; King, L. J.; Knauer, J. B.

    1980-07-01

    This report discusses the Submerged Demineralizer System (SDS) flowsheet for decontamination of the high-activity-level water at the Three Mile Island Unit 2 Nuclear Power Station was evaluated at Oak Ridge National Laboratory in a study that included filtration tests, ion exchange column tests, and ion exchange distribution tests. The contaminated waters, the SDS flowsheet, and the experiments made are described. The experimental results were used to predict the SDS performance and to indicate potential improvements.

  16. 县级供电公司废旧物资管理%Waste and Old Material Management in County Level Power Supply Company

    尹迎

    2014-01-01

    近年来,随着电网基建、大修、技改、农网升级工程力度的不断加大,县级供电公司拆除原有线路和设备等废旧物资的数量呈逐年递增趋势。但由于管理执行力度不够等原因,废旧物资的管理尚存在欠缺之处。文章分析了加强废旧物资管理的必要性以及具体方法,希望对提升县级供电公司的废旧物资管理水平起到有益的作用。%In recent years, with the increasing of the grid capital construction, overhaul, technical im-provement, rural power grid upgrade, the number of original lines, equipments and other waste and old materials dismantled by the county level power supply company shows a trend of increasing year by year. But due to not enough management enforcement strength, the management of waste and old materials is insufficient.This paper analyzes the necessity and specific methods to strengthen the management of waste and old materials, to hope to play a useful role in enhancing the level of waste and old materials management of county level power supply company.

  17. Electric Vehicle to Power Grid Integration Using Three-Phase Three-Level AC/DC Converter and PI-Fuzzy Controller

    Khairy Sayed

    2016-07-01

    Full Text Available This paper presents the control and simulation of an electric vehicle (EV charging station using a three-level converter on the grid-side as well as on the EV-side. The charging station control schemes with three-level AC/DC power conversion and a bidirectional DC/DC charging regulator are described. The integration of EVs to the power grid provides an improvement of the grid reliability and stability. EVs are considered an asset to the smart grid to optimize effective performance economically and environmentally under various operation conditions, and more significantly to sustain the resiliency of the grid in the case of emergency conditions and disturbance events. The three-level grid side converter (GSC can participate in the reactive power support or grid voltage control at the grid interfacing point or the common coupling point (PCC. A fuzzy logic proportional integral (FL-PI controller is proposed to control the GSC converter. The controllers used are verified and tested by simulation to evaluate their performance using MATLAB/SIMULINK. The comparison of a PI-controller and a PI-Fuzzy controller for the EV charging station shows the effectiveness of the proposed FL-PI controller over conventional PI controller for same circuit operating conditions. A good performance for PI-Fuzzy in terms of settling time and peak overshoot can observed from the simulation results.

  18. Instantaneous characteristics simulation and analysis on three-level brushless AC synchronous generators of aeronautic constant speed and frequency AC power system

    Ma, Xiaohe; Shen, Songhua

    2006-11-01

    This paper mainly introduces theoretical analysis and experimental results of instantaneous characteristics on a certain three level brushless three-phase AC synchronous generators. The analysis, modeling and simulations with Simplorer software of Ansoft Company are carried out. It establishes three level generator models, gives theoretical relation matrix equation, and simulates some instantaneous characteristics. Design of the system requires reliable simulation tools with comprehensive component libraries capable of dealing with complex system behavior. The simulation results verify that the proposed system model can efficiently simulate the instantaneous characteristics of the real AC generator system. It gives better design experiences and digital methods for aeronautic constant speed and frequency AC power system.

  19. Coupling and power handling of the new Tore Supra LHCD launcher

    Bibet, Ph. E-mail: bibet@drfc.cad.cea.fr; Ekedahl, A.; Froissard, Ph.; Kazarian, F.; Bertrand, E.; Dutheil, S.; Tanaskovic, L

    2001-10-01

    A new LHCD launcher, designed to inject 4 MW during 1000 s, has been installed on Tore Supra and successfully tested. A power of 3 MW with 7% power reflection coefficient has been reached. The coupling has been studied for various plasma parameters and positions, in order to study the robustness of the mode converter used in the antenna to divide the power into three in the poloidal direction. Due to the reduced electric field and the very efficiently water-cooled guard limiter, the temperature increase induced by the acceleration of electrons in the near field has been drastically reduced.

  20. Arc Power Limit and Distribution on the Large Negative Ion Source Based on JT-60 NNBI

    LEIGuangjiu; N.Umeda; M.Kawai; T.Yamamoto; M.Kuriyama; T.Ohga; N.Ebisawa; T.Yamazaki; M.Kusaka; K.Kikuchi; S.Hikida; K.Usui; M.Kazawa; S.Numazawa; K.Mogaki; A.Honda; F.Satoh; S.Norio; K.Ooshima

    2001-01-01

    The target of the large negative ion source based on neutral beam injection (N-NBI) is to produce neutral beam current of 22 A and beam power of 10 MW at 500 keV with duration time of 10 s. Since it was successfully operated in 1996, the 5.3 MW neutral beam power at 380 keV with duration time of 3 s has been achieved. In recent years improving and enhancing the beam power are going on. Several reasons such as plasma non-uniformity, higher beam density at the upper region in the beam profile,

  1. A Refined Self-Tuning Filter-Based Instantaneous Power Theory Algorithm for Indirect Current Controlled Three-Level Inverter-Based Shunt Active Power Filters under Non-sinusoidal Source Voltage Conditions

    Yap Hoon

    2017-02-01

    Full Text Available In this paper, a refined reference current generation algorithm based on instantaneous power (pq theory is proposed, for operation of an indirect current controlled (ICC three-level neutral-point diode clamped (NPC inverter-based shunt active power filter (SAPF under non-sinusoidal source voltage conditions. SAPF is recognized as one of the most effective solutions to current harmonics due to its flexibility in dealing with various power system conditions. As for its controller, pq theory has widely been applied to generate the desired reference current due to its simple implementation features. However, the conventional dependency on self-tuning filter (STF in generating reference current has significantly limited mitigation performance of SAPF. Besides, the conventional STF-based pq theory algorithm is still considered to possess needless features which increase computational complexity. Furthermore, the conventional algorithm is mostly designed to suit operation of direct current controlled (DCC SAPF which is incapable of handling switching ripples problems, thereby leading to inefficient mitigation performance. Therefore, three main improvements are performed which include replacement of STF with mathematical-based fundamental real power identifier, removal of redundant features, and generation of sinusoidal reference current. To validate effectiveness and feasibility of the proposed algorithm, simulation work in MATLAB-Simulink and laboratory test utilizing a TMS320F28335 digital signal processor (DSP are performed. Both simulation and experimental findings demonstrate superiority of the proposed algorithm over the conventional algorithm.

  2. 中点钳位型中压三电平风电变流器的损耗分析%Power Loss Analysis of NPC Medium-voltage Three-level Converters for Wind Power Generation System

    黄伟煌; 胡书举; 许洪华

    2014-01-01

    中点钳位(NPC)型中压三电平变流器在兆瓦级风电机组中具有广阔的应用前景。由于变流器容量及电压等级较高,功率器件的损耗是一个不容忽视的问题。文中详细分析了各个功率器件的开关动作与实际电流通路,在此基础上推导了其损耗的实用计算公式,指出了损耗在机侧变流器和网侧变流器之间的不同分布,为变流器的散热设计提供参考,并结合风力发电的特点,研究了功率波动对变流器效率的影响,得出了变流器的效率与功率成正相关的结论。最后,通过MATLAB/Simulink与GH Bladed的联合仿真系统,对分析结果进行了验证。%The neutral point clamping (NPC) three-level converters have broad application prospects with megawatt wind turbines.The power losses of the switching devices must be considered in such high-power applications.Practical loss-calculating formulas are derived based on the analysis of the conduction and switching principles of the converters.The difference between the motor-side power converter (MPC) and the grid-side power converter (GPC) in power losses distribution is identified.Combined with the characteristics of wind power,the influence of power fluctuation on efficiency is also analyzed.It is concluded that the efficiency has positive correlation with the converted power.Simulation results of a co-simulation platform using MATLAB/Simulink and GH Bladed show the validity of the analysis.

  3. Differences in Power Structures Regarding Access to Natural Resources at the Village Level in Central Sulawesi (Indonesia

    Jan Barkmann

    2008-01-01

    Full Text Available The mountain forests of the Indonesian province of Central Sulawesi include core areas of the global Wallacea biodiversity “hotspot”. Remote sensing data indicated that deforestation rates around Central Sulawesi’s Lore-Lindu National Park differ more strongly between villages than could be explained by differences in the individual characteristics of the village households as assessed by quantitative village censuses. This setting provided the background for a study into inter-village differences in power structures regarding access to natural resources. Our results are abstracted from 3*10 semi-structured, qualitative interviews with key informants from the leading groups of autochthonous and migrant households of three contrasting villages. In village A, nearly feudal power relationships are exerted by a group of local “first settler” families that dominate formal village leadership as well as the influential Council of Traditional Leaders (Lembaga Adat, and that restrict deforestation and land transactions. No such institutional restrictions exist in village C. Traditional power relationships are replaced by economic power based on petty capitalist type production of the international agricultural commodity cocoa. Deforestation is muchhigher in village C. In village B, traditional institutions and power structures still appear in place although land transactions are less restricted than in village A, resulting also in high deforestation rates. While contrasting problematic social effects, our study highlights the potential efficacy of traditional institutions in the regulation of access to resources. ----- Die Bergregenwälder Zentralsulawesis sind Teil des globalen Wallacea-Biodiversität-"Hotspots" und beheimaten viele endemische Tier- und Pflanzenarten. Die Entwaldung im Bereich des dortigen Lore-Lindu Nationalparks unterscheidet sich zwischen umliegenden Dörfern stärker, als dies durch quantitative Haushaltsdaten zu erkl

  4. A new balancing three level three dimensional space vector modulation strategy for three level neutral point clamped four leg inverter based shunt active power filter controlling by nonlinear back stepping controllers.

    Chebabhi, Ali; Fellah, Mohammed Karim; Kessal, Abdelhalim; Benkhoris, Mohamed F

    2016-07-01

    In this paper is proposed a new balancing three-level three dimensional space vector modulation (B3L-3DSVM) strategy which uses a redundant voltage vectors to realize precise control and high-performance for a three phase three-level four-leg neutral point clamped (NPC) inverter based Shunt Active Power Filter (SAPF) for eliminate the source currents harmonics, reduce the magnitude of neutral wire current (eliminate the zero-sequence current produced by single-phase nonlinear loads), and to compensate the reactive power in the three-phase four-wire electrical networks. This strategy is proposed in order to gate switching pulses generation, dc bus voltage capacitors balancing (conserve equal voltage of the two dc bus capacitors), and to switching frequency reduced and fixed of inverter switches in same times. A Nonlinear Back Stepping Controllers (NBSC) are used for regulated the dc bus voltage capacitors and the SAPF injected currents to robustness, stabilizing the system and to improve the response and to eliminate the overshoot and undershoot of traditional PI (Proportional-Integral). Conventional three-level three dimensional space vector modulation (C3L-3DSVM) and B3L-3DSVM are calculated and compared in terms of error between the two dc bus voltage capacitors, SAPF output voltages and THDv, THDi of source currents, magnitude of source neutral wire current, and the reactive power compensation under unbalanced single phase nonlinear loads. The success, robustness, and the effectiveness of the proposed control strategies are demonstrated through simulation using Sim Power Systems and S-Function of MATLAB/SIMULINK.

  5. 14C levels in the vicinity of the Fukushima Dai-ichi Nuclear Power Plant prior to the 2011 accident

    Xu, Sheng; Cook, Gordon T.; Cresswell, Alan J.

    2016-01-01

    A 50-year-old Japanese cedar (Cryptomeria japonica) from Okuma, ∼1 km southwest of the Fukushima Dai-ichi Nuclear Power Plant, was cored and each annual ring was analysed for 14C. The 14C specific activity values varied from 330.4 Bq kg−1 C in the tree ring formed in 1971 to 231.2 Bq kg−1 C...... discharges from the reactors during their normal operations. In addition, the specific activities are positively correlated with the annual electricity generation values. The excess 14C specific activities were ... and consequently no significant radiological impact of atmospheric 14C discharges from the FDNPP during the entire period of normal operations. Additionally, no 14C pulse in activity can be observed in the year 2011 ring. This might be caused by a limited 14C release from the damaged reactors during the accident...

  6. Maximum power point tracking for photovoltaic applications by using two-level DC/DC boost converter

    Moamaei, Parvin

    Recently, photovoltaic (PV) generation is becoming increasingly popular in industrial applications. As a renewable and alternative source of energy they feature superior characteristics such as being clean and silent along with less maintenance problems compared to other sources of the energy. In PV generation, employing a Maximum Power Point Tracking (MPPT) method is essential to obtain the maximum available solar energy. Among several proposed MPPT techniques, the Perturbation and Observation (P&O;) and Model Predictive Control (MPC) methods are adopted in this work. The components of the MPPT control system which are P&O; and MPC algorithms, PV module and high gain DC-DC boost converter are simulated in MATLAB Simulink. They are evaluated theoretically under rapidly and slowly changing of solar irradiation and temperature and their performance is shown by the simulation results, finally a comprehensive comparison is presented.

  7. State of Charge-Based Active Power Sharing Method in a Standalone Microgrid with High Penetration Level of Renewable Energy Sources

    Yun-Su Kim

    2016-06-01

    Full Text Available Standalone microgrids, which are mainly constructed on island areas have low system inertia, may result large frequency deviations even for small load change. Moreover, increasing penetration level of renewable energy sources (RESs into standalone microgrids makes the frequency stability problem even worse. To overcome this problem, this paper proposes an active power sharing method with zero frequency deviations. To this end, a battery energy storage system (BESS is operated as constant frequency (CF control mode, whereas the other distributed generations (DGs are operated as an active and reactive power (PQ control mode. As a result, a state of charge (SOC of the BESS is changed as the system load varies. Based on the SOC deviation, DGs share the load change. The SOC data is assumed to be sent via communication system, hence the communication time delay is considered. To enhance reliability, controllers of DGs are designed to take account of the failure of communication system. The simulation results show that active power can be shared among DGs according to desired ratio without frequency deviations even for large variation of output power of RESs.

  8. Effects of exercise in polluted air on the aerobic power, serum lactate level and cell blood count of active individuals

    Mehdi Kargarfard

    2011-01-01

    Conclusions: Exercise in high-polluted air resulted in a significant reduction in the performance at submaximal levels of physical exertion. Therefore, the acute exposure to polluted air may cause a significant reduction in the performance of active individuals. The clinical importance of these findings should be assessed in longitudinal studies.

  9. [Hygienic problems in the location of modern wind electric power stations in their design].

    Kireeva, I S; Makhniuk, V M; Akimenko, V Ia; Dumanskiĭ, Iu D; Semashko, P V

    2013-01-01

    Hygienic aspects of the placement of wind power plants (WPP) in connection with the intensive development of wind power and the lack of systematic information on their effects of the environment and living conditions of the population are becoming more actual. In the article there are considered results of the sanitary-epidemiological expertise of the construction project of three modern large wind farm (the South - Ukrainian, Tiligulskaya and Pokrovskaya) with a total capacity offrom 180 to 500 MW of wind farms with 2.3 MW power generators of wind turbines. It is shown that in the process of wind farm construction a contamination of the environment (air soil, ground water) may take place due to the working of construction equipment and vehicle, excavation, welding and other operations, in the exploitation of wind farm there can be created elevated levels of acoustic and electromagnetic pollution in the neighborhood and emergencies with the destruction of WPP in adverse weather conditions. Based on the calculations presented in the projects, and the analysis of data on the impact offoreign windfarm on the environment it was found that the limiting factor of the influence is the wind farm noise pollution in the audio frequency range that extends beyond the territory of wind fields, electromagnetic radiation is recorded within the hygienic standards and below only in the immediate vicinity of its sources (electrical equipment and power lines). For considered modern wind farms there was grounded sanitary protective zone with dimensions of 700 mfrom the outermost wind turbines by the noise and it was recommended compliance distance of200 mfrom the wind turbine to limit any activity and people staying in times of possible emergency situations in adverse weather conditions.

  10. Estimation of an Effective Young’s Modulus of Elasticity in the Locality of the Gabčíkovo Hydrology Power Plant by Geometric Leveling

    Mojzeš Marcel

    2015-03-01

    Full Text Available The Gabčíkovo hydroelectric power plant is located in a complicated geological environment (gravel sub-soil and a high groundwater level. Excavation work started after the withdrawal of water in the autumn of 1984 and lasted until the autumn of 1986. A basic geodetic control network with a special monument was founded before the excavation work began. This network served for the setting-out of the hydroelectric power plant as well as for the control of the excavation work. The repeated geodetic control measurements have been evaluated and presented at many seminars and conferences. Monitoring the horizontal and vertical stability of the geodetic control network during the general site excavation showed significant horizontal and vertical deformations. The paper is focused on an estimation of an effective Young's modulus of elasticity in the area studied.

  11. Power electronic topology and switching-concept for identification of the grid impedance at medium-voltage-level; Leistungselektronisches Schaltungskonzept zur Identifikation der Netzimpedanz auf der Mittelspannungsebene

    Do, Thanh Trung; Jordan, Michael; Langkowski, Hauke; Schulz, Detlef [Helmut-Schmidt-Univ., Hamburg (Germany). Professur fuer Elektrische Energiesysteme; Leutwyler, Reto [ABB Switzerland Ltd., Lenzburg (Switzerland). Semiconductors

    2011-07-01

    The grid impedance at a point of common coupling (PCC) is an important parameter for grid integration of Renewable Energies, because it determines the maximum input power capacity of the corresponding PCC. The grid impedance is time and frequency dependent, which makes an analytical or simulative identification challenging. Therefore in practise the data obtained from these calculations are often incorrect and do not reflect the real grid structure. In order to determine the grid impedance more accurately the Helmut-Schmidt-University is developing a novel measurement device to identify the time and frequency dependent grid impedance on the medium-voltage-level up to 20 kVrms. For the application in medium-voltage-grids a special switching concept with high voltage thyristors and innovative presspack-IGBTs has been developed in cooperation with ABB Switzerland Ltd./Semiconductors. This contribution presents the basic grid impedance measurement method and its realization with power electronic components. (orig.)

  12. THE EFFECT OF CAFFEINE CONSUMPTION ON THE NON-AEROBIC POWER, THE FATIGUE INDEX AND THE BLOOD LACTATE LEVELS IN THE MALE ATHLETE STUDENTS

    Ranjbar Rouhola

    2010-06-01

    Full Text Available The main purpose of this research is to study the effect of caffeine consumption on the non-aerobic power, the fatigue index and the blood lactate levels in the male athlete students. Therefore, 16 individuals with the average weight (68/1 +_ 9/1kg, height (1/73+_7cm, and age (24+_2 years were selected based on the simple-randomized method from among volunteer participants, and they were divided as match pairs, based on pre-examined fatigue index, into the two groups of caffeine (n=8 and placebo (n=8. Subjects were asked to refrain from having any intensive physical activity 24 hours before the test starts and avoid eating or drinking any caffeine foods or drinks 48 hours before the test. The primary RAST test (pre-test was performed at least 4 hours after having a meal, and then the individuals blood lactate levels was measured after 6 minutes of the test. The secondary RAST test was done after a week exactly like the first session. The subjects continued caffeine consumption as usual and interrupt it 48 hours prior to the next test. In post-test, the subjects took 6mg caffeine or placebo in the form of gelatin capsules per one kilogram of their weight one hour prior to the test. The analysis of the result, with applying the statistical t-test method (p≤0.05 to the dependent and independent groups, showed that consumption of caffeine has a significant positive effect on average power; minimum power and fatigue index, while it does not have any significant effect on maximum power and the amount of blood lactate. It seems that caffeine consumption is effective in the recovery of fast short-term shuttle activities.

  13. Improvement of level-1 PSA computer code package - Modeling and analysis for dynamic reliability of nuclear power plants

    Lee, Chang Hoon; Baek, Sang Yeup; Shin, In Sup; Moon, Shin Myung; Moon, Jae Phil; Koo, Hoon Young; Kim, Ju Shin [Seoul National University, Seoul (Korea, Republic of); Hong, Jung Sik [Seoul National Polytechnology University, Seoul (Korea, Republic of); Lim, Tae Jin [Soongsil University, Seoul (Korea, Republic of)

    1996-08-01

    The objective of this project is to develop a methodology of the dynamic reliability analysis for NPP. The first year`s research was focused on developing a procedure for analyzing failure data of running components and a simulator for estimating the reliability of series-parallel structures. The second year`s research was concentrated on estimating the lifetime distribution and PM effect of a component from its failure data in various cases, and the lifetime distribution of a system with a particular structure. Computer codes for performing these jobs were also developed. The objectives of the third year`s research is to develop models for analyzing special failure types (CCFs, Standby redundant structure) that were nor considered in the first two years, and to complete a methodology of the dynamic reliability analysis for nuclear power plants. The analysis of failure data of components and related researches for supporting the simulator must be preceded for providing proper input to the simulator. Thus this research is divided into three major parts. 1. Analysis of the time dependent life distribution and the PM effect. 2. Development of a simulator for system reliability analysis. 3. Related researches for supporting the simulator : accelerated simulation analytic approach using PH-type distribution, analysis for dynamic repair effects. 154 refs., 5 tabs., 87 figs. (author)

  14. Systematic evaluation of a secondary method for measuring diagnostic-level medical ultrasound transducer output power based on a large-area pyroelectric sensor

    Zeqiri, B.; Žauhar, G.; Rajagopal, S.; Pounder, A.

    2012-06-01

    A systematic study of the application of a novel pyroelectric technique to the measurement of diagnostic-level medical ultrasound output power is described. The method exploits the pyroelectric properties of a 0.028 mm thick membrane of polyvinylidene fluoride (PVDF), backed by an acoustic absorber whose ultrasonic absorption coefficient approaches 1000 dB cm-1 at 3 MHz. When exposed to an ultrasonic field, absorption of ultrasound adjacent to the PVDF-absorber interface results in heating and the generation of a pyroelectric output voltage across gold electrodes deposited on the membrane. For a sensor large enough to intercept the whole of the acoustic beam, the output voltage can be calibrated for the measurement of acoustic output power. A number of key performance properties of the method have been investigated. The technique is very sensitive, with a power to voltage conversion factor of typically 0.23 V W-1. The frequency response of a particular embodiment of the sensor in which acoustic power reflected at the absorber-PVDF interface is subsequently returned to the pyroelectric membrane to be absorbed, has been evaluated over the frequency range 1.5 MHz to 10 MHz. This has shown the frequency response to be flat to within ±4%, above 2.5 MHz. Below this frequency, the sensitivity falls by 20% at 1.5 MHz. Linearity of the technique has been demonstrated to within ±1.6% for applied acoustic power levels from 1 mW up to 120 mW. A number of other studies targeted at assessing the achievable measurement uncertainties are presented. These involve: the effects of soaking, the influence of the angle of incidence of the acoustic beam, measurement repeatability and sensitivity to transducer positioning. Additionally, over the range 20 °C to 30 °C, the rate of change in sensitivity with ambient temperature has been shown to be +0.5% °C-1. Implications of the work for the development of a sensitive, traceable, portable, secondary method of ultrasound output power

  15. Comparison of the Effect of Energy Drinks with a Simple Carbohydrate Solution on Anaerobic Power, Fatigue Index and Blood Lactate Level

    G Forozesh

    2012-01-01

    Full Text Available Introduction: Nowadays, the consumption of energy drinks has been increased among athletes due to the extensive advertisings of manufacturers about their effects on athletes' performance. The purpose of this study was to compare the effect of Redbull energy drink with simple carbohydrate solution on anaerobic power, fatigue index and blood lactate levels in the male students of physical education. Methods: Ten male students were randomly selected from 20 volunteer students. Their mean age, height and weight was 21.1±1.8 years, 170.7±7.2 cm and 63.3±5 kg, respectively. All 10 subjects were tested at three stages, first step after the consumption of Redbull energy drink(6 ml/kg body weight, the second step after drinking a carbohydrate solution(6 ml/kg body weight that was iso-caloric with Redbull, and third step, after drinking placebo. Anaerobic test, including Wingate 30 second test was performed at all three stages(in the same way 40 minutes after drinks. We used Kolmogorov Smirnov test to evaluate the normality of distribution and dependent t-test to compare the results of the three stages. Results: The results showed that anaerobic power after Redbull consumption was lower than carbohydrate solution or placebo consumption(p=0.005 and p=0.002, respectively. Fatigue index and lactate level after 2 and 6 minutes was not significantly different among three groups(P>0.05. Conclusion: The overall results showed that consumption of Redbull energy drinks not only doesn’t have a positive effect on improvement of anaerobic power and lactate level comparing carbohydrate solution, but also is harmful in these cases.

  16. Implementation of a Sage-Based Stirling Model Into a System-Level Numerical Model of the Fission Power System Technology Demonstration Unit

    Briggs, Maxwell H.

    2011-01-01

    The Fission Power System (FPS) project is developing a Technology Demonstration Unit (TDU) to verify the performance and functionality of a subscale version of the FPS reference concept in a relevant environment, and to verify component and system models. As hardware is developed for the TDU, component and system models must be refined to include the details of specific component designs. This paper describes the development of a Sage-based pseudo-steady-state Stirling convertor model and its implementation into a system-level model of the TDU.

  17. Power Talk

    Stefanovic, Cedomir; Popovski, Petar; Angjelichinoski, Marko

    2015-01-01

    We introduce a novel communication strategy for DC Micro Grids (MGs), termed power talk, in which the devices communicate by modulating the power levels in the DC bus. The information is transmitted by varying the parameters that the MG units use to control the level of the common bus voltage......, while it is received by processing the bus measurements that units perform. This implies that the communication does not require a dedicated modem, but instead it is piggybacked on top of the power electronics. The communication is challenged by the random fluctuations of the voltage level due...

  18. Power of the policy: how the announcement of high-stakes clinical examination altered OSCE implementation at institutional level

    Lin Chi-Wei

    2013-01-01

    Full Text Available Abstract Background The Objective Structured Clinical Examination (OSCE has been widely applied as a high-stakes examination for assessing physicians’ clinical competency. In 1992, OSCE was first introduced in Taiwan, and the authorities announced that passing the OSCE would be a prerequisite for step-2 medical licensure examination in 2013. This study aimed to investigate the impacts of the announced national OSCE policy on implementation of OSCE at the institutional level. Further, the readiness and the recognition of barriers toward a high-stakes examination were explored. Methods In 2007 and 2010, the year before and after the announcement of high-stakes OSCE policy in 2008, respectively, questionnaires on the status of OSCE implementation were distributed to all hospitals with active OSCE programs in Taiwan. Information on OSCE facilities, equipment, station length, number of administrations per year, and the recognition of barriers to the success of implementing an OSCE were collected. The missing data were completed by telephone interviews. The OSCE format, administration, and facilities before and after the announcement of the nationwide OSCE policy were compared. Results The data were collected from 17 hospitals in 2007 and 21 in 2010. Comparing the OSCE formats between 2007 and 2010, the number of stations increased and the station length decreased. The designated space and the equipment for OSCE were also found to have been improved. As for the awareness of OSCE implementation barriers, the hospital representatives concerned mostly about the availability and quality of standardized patients in 2007, as well as space and facilities in 2010. Conclusions The results of this study underscored an overall increase in the number of OSCE hospitals and changes in facilities and formats. While recruitment and training of standardized patients were the major concerns before the official disclosure of the policy, space and facilities became the

  19. INDEPENDENT VERIFICATION SURVEY OF THE SPRU LOWER LEVEL HILLSIDE AREA AT THE KNOLLS ATOMIC POWER LABORATORY NISKAYUNA, NEW YORK

    Harpenau, Evan M.; Weaver, Phyllis C.

    2012-06-06

    During August 10, 2011 through August 19, 2011, and October 23, 2011 through November 4, 2011, ORAU/ORISE conducted verification survey activities at the Separations Process Research Unit (SPRU) site that included in-process inspections, surface scans, and soil sampling of the Lower Level Hillside Area. According to the Type-B Investigation Report, Sr-90 was the primary contributor to the majority of the activity (60 times greater than the Cs-137 activity). The evaluation of the scan data and sample results obtained during verification activities determined that the primary radionuclide of concern, Sr-90, was well below the agreed upon soil cleanup objective (SCO) of 30 pCi/g for the site. However, the concentration of Cs-137 in the four judgmental samples collected in final status survey (FSS) Units A and B was greater than the SCO. Both ORAU and aRc surveys identified higher Cs-137 concentrations in FSS Units A and B; the greatest concentrations were indentified in FSS Unit A.

  20. Partnership Funding in flood risk management: multi-level stakeholder engagement – a question of roles and power

    Thale Thomas

    2016-01-01

    Full Text Available The paper examines the new flood risk policy discussion in England and Wales. The summer floods in England in 2007 caused large damages to the environment, economy and humanity. Following this key flood event, the Government has started to redefine the national flood and coastal risk management policy in England and Wales. The key issue in the new policy agenda is to encourage the responsibilities of local authorities and reduce the central role of flood risk management. This decentralisation in flood risk management has a series of consequences in the development of new governance structures. The main reason for this shift from central to local level is the belief that local authorities deal with public administration tasks in a more efficient way. Nevertheless, the main problem is the gap between the delegated tasks and the lack of transfer of resources, especially the issue concerning funding is still unclear and unresolved. This constraint will go with fiscal and administration cuts. The consequences will be (1 ‘hollowing out’ of the Government with the downscaling of the responsibility towards local actors and (2 without proportional transfer of resources to local authorities they will not be able to deal with new tasks. Therefore, in practice there are many limitations, barriers and concerns with the new policy direction.

  1. The 5-hydroxytryptamine4 receptor agonists prucalopride and PRX-03140 increase acetylcholine and histamine levels in the rat prefrontal cortex and the power of stimulated hippocampal θ oscillations.

    Johnson, David E; Drummond, Elena; Grimwood, Sarah; Sawant-Basak, Aarti; Miller, Emily; Tseng, Elaine; McDowell, Laura L; Vanase-Frawley, Michelle A; Fisher, Katherine E; Rubitski, David M; Stutzman-Engwall, Kim J; Nelson, Robin T; Horner, Weldon E; Gorczyca, Roxanne R; Hajos, Mihaly; Siok, Chester J

    2012-06-01

    5-Hydroxytryptamine (5-HT)(4) receptor agonists reportedly stimulate brain acetylcholine (ACh) release, a property that might provide a new pharmacological approach for treating cognitive deficits associated with Alzheimer's disease. The purpose of this study was to compare the binding affinities, functional activities, and effects on neuropharmacological responses associated with cognition of two highly selective 5-HT(4) receptor agonists, prucalopride and 6,7-dihydro-4-hydroxy-7-isopropyl-6-oxo-N-[3-(piperidin-1-yl)propyl]thieno[2,3-b]pyridine-5-carboxamide (PRX-03140). In vitro, prucalopride and PRX-03140 bound to native rat brain 5-HT(4) receptors with K(i) values of 30 nM and 110 nM, respectively, and increased cAMP production in human embryonic kidney-293 cells expressing recombinant rat 5-HT(4) receptors. In vivo receptor occupancy studies established that prucalopride and PRX-03140 were able to penetrate the brain and bound to 5-HT(4) receptors in rat brain, achieving 50% receptor occupancy at free brain exposures of 330 nM and 130 nM, respectively. Rat microdialysis studies revealed that prucalopride maximally increased ACh and histamine levels in the prefrontal cortex at 5 and 10 mg/kg, whereas PRX-03140 significantly increased cortical histamine levels at 50 mg/kg, failing to affect ACh release at doses lower than 150 mg/kg. In combination studies, donepezil-induced increases in cortical ACh levels were potentiated by prucalopride and PRX-03140. Electrophysiological studies in rats demonstrated that both compounds increased the power of brainstem-stimulated hippocampal θ oscillations at 5.6 mg/kg. These findings show for the first time that the 5-HT(4) receptor agonists prucalopride and PRX-03140 can increase cortical ACh and histamine levels, augment donepezil-induced ACh increases, and increase stimulated-hippocampal θ power, all neuropharmacological parameters consistent with potential positive effects on cognitive processes.

  2. Comparison of power performance and noise between Aeolus 2 and Naesudden 2

    Albers, C.; Hinsch, J.; Gabriel, J.; Klug, H. [Deutsches Windenergie-Institut gGmbH (DEWI), Wilhelmshaven (Germany); Ronsten, G. [Aeronautical Research Inst. of Sweden, Bromma (Sweden); Simonssen, B. [KM Akustikbyraan, Solna (Sweden)

    1996-12-01

    The German Wind Energy Institute DEWI and the Aeronautical Research Institute of Sweden FFA perform comparing measurements at the 3 MW sister turbines Aeolus II and Naesudden II in the framework of WEGA II (CAN-Project). Results exist concerning the comparison of power performance and noise emission. Load measurements have been carried out but no comparing results are available yet. In the case of Aeolus II interesting effects of different meteorological conditions on the power performance have been found. The project will continue till the end of 1996. 6 refs, 12 figs, 1 tab

  3. Power and polarization dependences of ultra-narrow electromagnetically induced absorption (EIA) spectra of 85 Rb atoms in degenerate two-level system

    Qureshi, Muhammad Mohsin; Rehman, Hafeez Ur; Noh, Heung-Ryoul; Kim, Jin-Tae

    2016-05-01

    We have investigated ultra-narrow EIA spectral features with respect to variations of polarizations and powers of pump laser beam in a degenerate two-level system of the transition of 85 Rb D2 transition line. Polarizations of the probe laser beam in two separate experiments were fixed at right circular and horizontal linear polarizations, respectively while the polarizations of the pump lasers were varied from initial polarizations same as the probe laser beams to orthogonal to probe polarizations. One homemade laser combined with AOMs was used to the pump and probe laser beams instead of two different lasers to overcome broad linewidths of the homemade lasers. Theoretically, probe absorption coefficients have been calculated from optical Bloch equations of the degenerate two level system prepared by a pump laser beam. In the case of the circular polarization, EIA signal was obtained as expected theoretically although both pump and probe beams have same polarization. The EIA signal become smaller as power increases and polarizations of the pump and probe beams were same. When the polarization of the pump beam was linear polarization, maximum EIA signal was obtained theoretically and experimentally. Experimental EIA spectral shapes with respect to variations of the pump beam polarization shows similar trends as the theoretical results.

  4. Development of methods for evaluation of electricity saving and load levelling measures. Part 3: Experimental assessment of the effect of a power conservation campaign

    Aalborg Nielsen, H.; Madsen, H. [Danmarks Tekniske Univ., Dept. of Mathematical Modelling (Denmark)

    1997-12-01

    The purpose of the project described in this report is to develop and to investigate methods for estimating effects of power conservation campaigns, and to estimate the effect of a particular campaign. The statistical approach of experimental design, followed by analysis of measurements is applied. Using a method known as cluster analysis prior to the initiation of the campaign, a number of substations for which measurements equipment was installed were combined into groups of highest possible similarity with respect to a number of features. It was decided to perform a campaign on a total of two substations. For this purpose the two groups of highest similarity were selected and one substation was chosen from each group to receive the campaign (the active substations). Since each of the two groups contained two substations this procedure left two substations for comparisons (the control substations). The overall results indicate a 10-12% reduction of the power consumption when carrying out a campaign. However, some difference is observed for the two pairs of active and control substations. Consequently, the extrapolation to other substations of similar kind will be difficult. When measuring the diurnal profile as the relative deviation from the daily level during the cycle, practically no effect of the campaign can be detected. However, the amplitude of the profile measured in units of power consumption depends strongly on the daily level. It is demonstrated that non-parametric and semi non-parametric methods, combined with traditional time series analysis and bootstrapping, are well suited as statistical tools for the analysis of data from these kinds of experiments. (au) EFP-95. 22 refs.

  5. The effects of incline and level-grade high-intensity interval treadmill training on running economy and muscle power in well-trained distance runners.

    Ferley, Derek D; Osborn, Roy W; Vukovich, Matthew D

    2014-05-01

    Despite a paucity of evidence, uphill running has been touted as a sport-specific resistance-to-movement training tactic capable of enhancing metabolic, muscular, and neuromuscular processes in distance runners in ways similar to previously established resistance-to-movement training methods, such as heavy and/or explosive strength training and plyometric training. Therefore, the purpose of this investigation included documenting the effects of incline and level-grade interval treadmill training on indices of running economy (RE) (i.e., oxygen consumption [VO2] and blood lactate [BLa] responses of submaximal running) and muscle power. Thirty-two well-trained distance runners (age, 27.4 ± 3.8 years; body mass, 64.8 ± 8.9 kg; height, 173.6 ± 6.4 cm; and VO2max, 60.9 ± 8.5 ml·min(-1)·kg(-1)) received assignment to an uphill (GHill = 12), level-grade (GFlat = 12), or control (GCon = 8) group. GHill and GFlat completed 12 interval and 12 continuous run sessions over 6 weeks, whereas GCon maintained their normal training. Dependent variables measured before and after training were VO2 and BLa at 2 separate velocities associated with lactate threshold (VLT) (VO2-60% and VO2-80%; and BLa-60% and BLa-80%, respectively); percentage of VO2max at lactate threshold (%VO2max at VLT); muscle power as assessed through a horizontal 5-jump test (5Jmax); and isokinetic knee extension and flexion at 3 angular velocities (90, 180, and 300°·s(-1)). Statistical significance was set to p ≤ 0.05. All groups significantly improved 5Jmax, VO2-60%, VO2-80%, BLa-60%, and BLa-80%. Additionally, GHill and GFlat significantly improved %VO2max at VLT. Other indices of RE and muscle power did not improve. We conclude incline treadmill training effective for improving the components of RE, but insufficient as a resistance-to-movement exercise for enhancing muscle power output.

  6. Wind Power in Georgia

    NONE

    2012-11-01

    opportunity Screening eight sites identified in the Wind Atlas of Georgia (2004) based on a preliminary assessment of the wind power potential, feasibility and construction costs of each site, points to Skra as the most feasible area for pilot development of wind power. The Skra site in Gori/Kareli regions has good (above 7 m/s at 100m) and steady wind resources, minimal land-use and environmental conflicts and high accessibility. An 80m wind measurement mast has recently been put up on the site by a Georgian company. The Skra site is estimated to potentially hold up to 35 3MW turbines (90m rotor diameter) or 45 2MW turbines (80m rotor diameter). The total capacity of the wind farm would thus be 105MW or 90MW respectively. A preliminary estimation for the annual energy production of the wind farm using 2,500 full-load-hours, gives production estimations of 260 GWh for a 105MW and 225 GWh for a 90MW wind farm on the site. Investment cost of the wind farm is estimated to be roughly 1.5 MEuro/MW, which amounts to 158 MEuro for a 105MW farm and 135 MEuro for a 90 MW farm. Several stakeholders in Georgia have expressed interest in using second hand turbines in order to reduce investment costs. Most available used turbines on the market are of sizes less than 2MW and the prize vary significantly depending especially on the capacity, age and make of the turbine. Other interesting sites in Georgia to explore further with an aim for wind power development include Chorokhi, Kutaisi, Samgori and Yagludja.(auth)

  7. Radioactive contamination of arthropods from different trophic levels in hilly and mountainous areas after the Fukushima Daiichi nuclear power plant accident.

    Tanaka, Sota; Hatakeyama, Kaho; Takahashi, Sentaro; Adati, Tarô

    2016-11-01

    In order to understand the influence of the Fukushima Daiichi nuclear power plant accident on the ecosystem in hilly and mountainous areas of Fukushima Prefecture, chronological changes in the levels of radiocesium in arthropod species were investigated. From 2012 to 2014, arthropods from different trophic levels were sampled and the air radiation dose rates at the sampling sites were analyzed. The air radiation dose rates showed a significant and constant reduction over the 2 years at the sampling sites in Fukushima. The median radiocesium concentration ((134)Cs + (137)Cs) detected in the rice grasshopper, Oxya yezoensis, and the Emma field cricket, Teleogryllus emma, dropped continuously to 0.080 and 0.078 Bq/g fresh weight, respectively, in 2014. In contrast, no significant reduction in radioactive contamination was observed in the Jorô spider, Nephila clavata, in which the level remained at 0.204 Bq/g in 2014. A significant positive correlation between radiocesium concentration and the air radiation dose rate was observed in the rice grasshopper, the Emma field cricket and the Jorô spider. The highest correlation coefficient (ρ = 0.946) was measured in the grasshopper.

  8. Is the SNARC effect related to the level of mathematics? No systematic relationship observed despite more power, more repetitions, and more direct assessment of arithmetic skill.

    Cipora, Krzysztof; Nuerk, Hans-Christoph

    2013-01-01

    The SNARC (spatial-numerical association of response codes) described that larger numbers are responded faster with the right hand and smaller numbers with the left hand. It is held in the literature that arithmetically skilled and nonskilled adults differ in the SNARC. However, the respective data are descriptive, and the decisive tests are nonsignificant. Possible reasons for this nonsignificance could be that in previous studies (a) very small samples were used, (b) there were too few repetitions producing too little power and, consequently, reliabilities that were too small to reach conventional significance levels for the descriptive skill differences in the SNARC, and (c) general mathematical ability was assessed by the field of study of students, while individual arithmetic skills were not examined. Therefore we used a much bigger sample, a lot more repetitions, and direct assessment of arithmetic skills to explore relations between the SNARC effect and arithmetic skills. Nevertheless, a difference in SNARC effect between arithmetically skilled and nonskilled participants was not obtained. Bayesian analysis showed positive evidence of a true null effect, not just a power problem. Hence we conclude that the idea that arithmetically skilled and nonskilled participants generally differ in the SNARC effect is not warranted by our data.

  9. Comparison of Field Measurements and EMT Simulation Results on a Multi-Level STATCOM for Grid Integration of London Array Wind Power Plant

    Glasdam, Jakob; Kocewiak, Łukasz Hubert; Hjerrild, Jesper;

    2014-01-01

    of the evaluation of the simulation models of the OWPP components. The purpose of this paper is to develop and validate an electromagnetic transient (EMT) generic model of the modular multi-level cascaded converter (MMCC) STATCOM based on comparison with field measurements. For this purpose, measurement data have......Simulation results are widely used in the design of electrical systems such as offshore wind power plants (OWPPs) and for determination of grid compliance. Measurements constitute an important part in the evaluation process of the OWPP, including passive and active components such as the static...... compensator (STATCOM). Quality measurement data allow the system designer to obtain real-life knowledge on the operating characteristics of the electrical component(s) for various operating scenarios of both the OWPP and the external grid. Furthermore, measurement data constitute an indispensable part...

  10. Voltage-Sharing Converter to Supply Single-Phase Asymmetrical Four-Level Diode-Clamped Inverter With High Power Factor Loads

    Boora, Arash A.; Nami, Alireza; Zare, Firuz

    2010-01-01

    The output voltage quality of some of the single-phase multilevel inverters can be improved when their dc-link voltages are regulated asymmetrically. Symmetrical and asymmetrical multilevel diode-clamped inverters have the problem of dc-link capacitor voltage balancing, especially when power factor...... of the load is close to unity. In this paper, a new single-inductor multi-output dc/dc converter is proposed that can control the dc-link voltages of a single-phase diode-clamped inverter asymmetrically to achieve voltage quality enhancement. The circuit of the presented converter is explained and the main...... equations are developed. A control strategy is proposed and explained in details. To validate the versatility of the proposed combination of the suggested dc–dc converter and the asymmetrical four-level diode-clamped inverter (ADCI), simulations and experiments have been directed. It is concluded...

  11. A novel power control strategy of Modular Multi-level Converter in HVDC-AC hybrid transmission systems for passive networks

    Hu, Zhenda; Wu, Rui; Yang, Xiaodong;

    2014-01-01

    With the development of High Voltage DC Transmission (HVDC) technology, there will be more and more HVDC-AC hybrid transmission system in the world. A basic challenge in HVDC-AC hybrid transmission systems is to optimize the power sharing between DC and AC lines, which become more severe when...... supplying power for passive networks, as the surplus power can only flow back to power grids through the AC lines. To deal with this issue, it demands not only accurate system capability design but also flexible power control strategy of power converters in VSC-HVDC. This paper proposes a novel power...

  12. Geothermal power, policy, and design: Using levelized cost of energy and sensitivity analysis to target improved policy incentives for the U.S. geothermal market

    Richard, Christopher L.

    At the core of the geothermal industry is a need to identify how policy incentives can better be applied for optimal return. Literature from Bloomquist (1999), Doris et al. (2009), and McIlveen (2011) suggest that a more tailored approach to crafting geothermal policy is warranted. In this research the guiding theory is based on those suggestions and is structured to represent a policy analysis approach using analytical methods. The methods being used are focus on qualitative and quantitative results. To address the qualitative sections of this research an extensive review of contemporary literature is used to identify the frequency of use for specific barriers, and is followed upon with an industry survey to determine existing gaps. As a result there is support for certain barriers and justification for expanding those barriers found within the literature. This method of inquiry is an initial point for structuring modeling tools to further quantify the research results as part of the theoretical framework. Analytical modeling utilizes the levelized cost of energy as a foundation for comparative assessment of policy incentives. Model parameters use assumptions to draw conclusions from literature and survey results to reflect unique attributes held by geothermal power technologies. Further testing by policy option provides an opportunity to assess the sensitivity of each variable with respect to applied policy. Master limited partnerships, feed in tariffs, RD&D, and categorical exclusions all result as viable options for mitigating specific barriers associated to developing geothermal power. The results show reductions of levelized cost based upon the model's exclusive parameters. These results are also compared to contemporary policy options highlighting the need for tailored policy, as discussed by Bloomquist (1999), Doris et al. (2009), and McIlveen (2011). It is the intent of this research to provide the reader with a descriptive understanding of the role of

  13. INSTALLATION OF A POST-ACCIDENT CONFINEMENT HIGH-LEVEL RADIATION MONITORING SYSTEM IN THE KOLA NUCLEAR POWER STATION (UNIT 2) IN RUSSIA

    GREENE,G.A.; GUPPY,J.G.

    1998-09-01

    This is the final report on the INSP project entitled, ``Post-Accident Confinement High-Level Radiation Monitoring System'' conducted by BNL under the authorization of Project Work Plan WBS 1.2.2.6 (Attachment 1). This project was initiated in February 1993 to assist the Russians in reducing risks associated with the continued operation of older Soviet-designed nuclear power plants, specifically the Kola VVER-440/230 Unit 2, through improved accident detection capability, specifically by the installation of a dual train high-level radiation detection system in the confinement of Unit 2 of the Kola NPP. The major technical objective of this project was to provide, install and make operational the necessary hardware inside the confinement of the Kola NPP Unit 2 to provide early and reliable warning of the release of radionuclides from the reactor into the confinement air space as an indication of the occurrence of a severe accident at the plant. In addition, it was intended to provide hands-on experience and training to the Russian plant workers in the installation, operation, calibration and maintenance of the equipment in order that they may use the equipment without continued US assistance as an effective measure to improve reactor safety at the plant.

  14. {sup 14}C emission from Swedish nuclear power plants and its effect on the {sup 14}C levels in the environment

    Stenstroem, K.; Erlandsson, Bengt; Hellborg, R.; Kiisk, M.; Persson, Per [Lund Univ. (Sweden). Dept. of Nuclear Physics; Mattsson, Soeren; Thornberg, C. [Lund Univ., Malmoe (Sweden). Dept. of Radiation Physics; Skog, G. [Lund Univ. (Sweden). Dept. of Quaternary Geology

    2000-02-15

    The radionuclide {sup 14}C is produced in all types of nuclear reactors mainly by neutron induced reactions in oxygen ({sup 17}O), nitrogen ({sup 14}N) and carbon ({sup 13}C). Part of the {sup 14}C created is continuously released during normal operation as airborne effluents in various chemical forms (such as CO{sub 2}, CO and hydrocarbons) to the surroundings. Because of the biological importance of carbon and the long physical half-life of {sup 14}C, it is of interest to measure the releases and their incorporation into living material. The {sup 14}C activity concentrations in annual tree rings and air around two Swedish nuclear power plants (Barsebaeck and Forsmark) as well as the background {sup 14}C activity levels from two reference sites in southern Sweden during 1973-1996 are presented in this report. In order to verify the reliability of the method some investigations have been conducted at two foreign nuclear sites, Sellafield fuel reprocessing plant in England, and Pickering nuclear generating station in Canada, where the releases of {sup 14}C are known to be substantial. Furthermore, results from some measurements in the vicinity of Paldiski submarine training centre in Estonia are presented. The results of the {sup 14}C measurements of air, vegetation and annual tree rings around the two Swedish nuclear power plants show very low enhancements of {sup 14}C, if at all above the uncertainty of the measurements. Even if the accuracy of the measurements of the annual tree rings is rather good (1-2%) the contribution of {sup 14}C from the reactors to the environment is so small that it is difficult to separate it from the prevailing background levels of {sup 14}C . This is the case for all sampling procedures: in air and vegetation as well as in annual tree rings. Only on a few occasions an actual increase is observed. However, although the calculations suffer from rather large uncertainties, the calculated release rate from Barsebaeck is in fair agreement

  15. Power Capability Investigation Based on Electrothermal Models of Press-pack IGBT Three-Level NPC and ANPC VSCs for Multimegawatt Wind Turbines

    Senturk, Osman Selcuk; Helle, Lars; Munk-Nielsen, Stig

    2012-01-01

    to provide reactive power support as an ancillary service. For multimegawatt full-scale wind turbines, power capability depends on converter topology and semiconductor switch technology. As power capability limiting factors, switch current, semiconductor junction temperature, and converter output voltage...... capability investigations regarding a sample grid code's reactive power requirement show that 3L-ANPC-VSC results in 32% better power capability than 3L-NPC-VSC at the switching frequency of 1050 Hz. Furthermore, 3L-ANPC-VSC with 57% higher switching frequency (1650 Hz) and 33% smaller switching ripple...

  16. Optimal Design of Stator Interior Permanent Magnet Machine with Minimized Cogging Torque for Wind Power Application

    Chen, Zhe; Zhang, Jianzhong; Cheng, Ming

    2008-01-01

    This paper proposes a new approach to minimize the cogging torque of a stator interior permanent magnet (SIPM) machine. The optimization of stator slot gap and permanent magnet is carried out and the cogging torque ripple is analyzed by using finite element analysis. Experiments on a prototype...... machine verify the theoretical analysis. A comparison between the improved SIPM generator and a radial flux permanent magnet synchronous generator for a 3-MW wind turbine is carried out. It shows that the proposed SIPM generator has the advantages of higher power density and lower cost....

  17. Hardware Accelerated Power Estimation

    Coburn, Joel; Raghunathan, Anand

    2011-01-01

    In this paper, we present power emulation, a novel design paradigm that utilizes hardware acceleration for the purpose of fast power estimation. Power emulation is based on the observation that the functions necessary for power estimation (power model evaluation, aggregation, etc.) can be implemented as hardware circuits. Therefore, we can enhance any given design with "power estimation hardware", map it to a prototyping platform, and exercise it with any given test stimuli to obtain power consumption estimates. Our empirical studies with industrial designs reveal that power emulation can achieve significant speedups (10X to 500X) over state-of-the-art commercial register-transfer level (RTL) power estimation tools.

  18. DC-Link Capacitor Voltage Regulation for Three-Phase Three-Level Inverter-Based Shunt Active Power Filter with Inverted Error Deviation Control

    Yap Hoon

    2016-07-01

    Full Text Available A new control technique known as inverted error deviation (IED control is incorporated into the main DC-link capacitor voltage regulation algorithm of a three-level neutral-point diode clamped (NPC inverter-based shunt active power filter (SAPF to enhance its performance in overall DC-link voltage regulation so as to improve its harmonics mitigation performances. In the SAPF controller, DC-link capacitor voltage regulation algorithms with either the proportional-integral (PI or fuzzy logic control (FLC technique have played a significant role in maintaining a constant DC-link voltage across the DC-link capacitors. However, both techniques are mostly operated based on a direct voltage error manipulation approach which is insufficient to address the severe DC-link voltage deviation that occurs during dynamic-state conditions. As a result, the conventional algorithms perform poorly with large overshoot, undershoot, and slow response time. Therefore, the IED control technique is proposed to precisely address the DC-link voltage deviation. To validate effectiveness and feasibility of the proposed algorithm, simulation work in MATLAB-Simulink and experimental implementation utilizing a TMS320F28335 Digital Signal Processor (DSP are performed. Moreover, conventional algorithms with PI and FLC techniques are tested too for comparison purposes. Both simulation and experimental results are presented, confirming the improvement achieved by the proposed algorithm in terms of accuracy and dynamic response in comparison to the conventional algorithms.

  19. Low-power laser irradiation suppresses inflammatory response of human adipose-derived stem cells by modulating intracellular cyclic AMP level and NF-κB activity.

    Wu, Jyun-Yi; Chen, Chia-Hsin; Wang, Chau-Zen; Ho, Mei-Ling; Yeh, Ming-Long; Wang, Yan-Hsiung

    2013-01-01

    Mesenchymal stem cell (MSC)-based tissue regeneration is a promising therapeutic strategy for treating damaged tissues. However, the inflammatory microenvironment that exists at a local injury site might restrict reconstruction. Low-power laser irradiation (LPLI) has been widely applied to retard the inflammatory reaction. The purpose of this study was to investigate the anti-inflammatory effect of LPLI on human adipose-derived stem cells (hADSCs) in an inflammatory environment. We showed that the hADSCs expressed Toll-like Receptors (TLR) 1, TLR2, TLR3, TLR4, and TLR6 and that lipopolysaccharide (LPS) significantly induced the production of pro-inflammatory cytokines (Cyclooxygenase-2 (Cox-2), Interleukin-1β (IL-1β), Interleukin-6 (IL-6), and Interleukin-8 (IL-8)). LPLI markedly inhibited LPS-induced, pro-inflammatory cytokine expression at an optimal dose of 8 J/cm². The inhibitory effect triggered by LPLI might occur through an increase in the intracellular level of cyclic AMP (cAMP), which acts to down-regulate nuclear factor kappa B (NF-κB) transcriptional activity. These data collectively provide insight for further investigations of the potential application of anti-inflammatory treatment followed by stem cell therapy.

  20. Co-Design Method and Wafer-Level Packaging Technique of Thin-Film Flexible Antenna and Silicon CMOS Rectifier Chips for Wireless-Powered Neural Interface Systems.

    Okabe, Kenji; Jeewan, Horagodage Prabhath; Yamagiwa, Shota; Kawano, Takeshi; Ishida, Makoto; Akita, Ippei

    2015-12-16

    In this paper, a co-design method and a wafer-level packaging technique of a flexible antenna and a CMOS rectifier chip for use in a small-sized implantable system on the brain surface are proposed. The proposed co-design method optimizes the system architecture, and can help avoid the use of external matching components, resulting in the realization of a small-size system. In addition, the technique employed to assemble a silicon large-scale integration (LSI) chip on the very thin parylene film (5 μm) enables the integration of the rectifier circuits and the flexible antenna (rectenna). In the demonstration of wireless power transmission (WPT), the fabricated flexible rectenna achieved a maximum efficiency of 0.497% with a distance of 3 cm between antennas. In addition, WPT with radio waves allows a misalignment of 185% against antenna size, implying that the misalignment has a less effect on the WPT characteristics compared with electromagnetic induction.

  1. Life performance of an EPR-insulated power cable exposed in service beyond 3 MGy in high-level radiation area

    Grüb, R.; Langeset, B.; Maier, P.; Schönbacher, H.

    1983-09-01

    Mechanical and electrical test results are reported for a power cable that has been installed for three and a half years in a high-level radiation area at the European Organization for Nuclear Research (CERN). The degradation of selected mechanical properties as a function of absorbed dose is compared with results of a short-term irradiation in a nuclear reactor. The tensile test specimens have been taken from the ethylene propylene rubber insulation and the polyvinyl chloride sheath material of the cable after exposure in service. For the measurement of breakdown voltage, short portions of insulated cable have been used. The aim of this work was to verify that the combined functional and environmental stress factors did not lead to more damage of the cable than was expected from the value of absorbed dose, and eventually to predict more precisely the service life of similar cables. The ratios of doses after service and short-term irradiation at 50% reduction of elongation at break were about 0.5 for the insulation and 1.0 for the sheath material at a dose of about 1 MGy. However, the breakdown voltage did not show any significant variation in the dose range covered up to 3.6 MGy. Therefore, a safe lower dose limit may readily be derived from accelerated tests, but the margin until failure in service remains to be determined.

  2. Low-power laser irradiation suppresses inflammatory response of human adipose-derived stem cells by modulating intracellular cyclic AMP level and NF-κB activity.

    Jyun-Yi Wu

    Full Text Available Mesenchymal stem cell (MSC-based tissue regeneration is a promising therapeutic strategy for treating damaged tissues. However, the inflammatory microenvironment that exists at a local injury site might restrict reconstruction. Low-power laser irradiation (LPLI has been widely applied to retard the inflammatory reaction. The purpose of this study was to investigate the anti-inflammatory effect of LPLI on human adipose-derived stem cells (hADSCs in an inflammatory environment. We showed that the hADSCs expressed Toll-like Receptors (TLR 1, TLR2, TLR3, TLR4, and TLR6 and that lipopolysaccharide (LPS significantly induced the production of pro-inflammatory cytokines (Cyclooxygenase-2 (Cox-2, Interleukin-1β (IL-1β, Interleukin-6 (IL-6, and Interleukin-8 (IL-8. LPLI markedly inhibited LPS-induced, pro-inflammatory cytokine expression at an optimal dose of 8 J/cm². The inhibitory effect triggered by LPLI might occur through an increase in the intracellular level of cyclic AMP (cAMP, which acts to down-regulate nuclear factor kappa B (NF-κB transcriptional activity. These data collectively provide insight for further investigations of the potential application of anti-inflammatory treatment followed by stem cell therapy.

  3. Co-Design Method and Wafer-Level Packaging Technique of Thin-Film Flexible Antenna and Silicon CMOS Rectifier Chips for Wireless-Powered Neural Interface Systems

    Kenji Okabe

    2015-12-01

    Full Text Available In this paper, a co-design method and a wafer-level packaging technique of a flexible antenna and a CMOS rectifier chip for use in a small-sized implantable system on the brain surface are proposed. The proposed co-design method optimizes the system architecture, and can help avoid the use of external matching components, resulting in the realization of a small-size system. In addition, the technique employed to assemble a silicon large-scale integration (LSI chip on the very thin parylene film (5 μm enables the integration of the rectifier circuits and the flexible antenna (rectenna. In the demonstration of wireless power transmission (WPT, the fabricated flexible rectenna achieved a maximum efficiency of 0.497% with a distance of 3 cm between antennas. In addition, WPT with radio waves allows a misalignment of 185% against antenna size, implying that the misalignment has a less effect on the WPT characteristics compared with electromagnetic induction.

  4. Far-Field Acoustic Power Level and Performance Analyses of F31/A31 Open Rotor Model at Simulated Scaled Takeoff, Nominal Takeoff, and Approach Conditions: Technical Report I

    Sree, Dave

    2015-01-01

    Far-field acoustic power level and performance analyses of open rotor model F31/A31 have been performed to determine its noise characteristics at simulated scaled takeoff, nominal takeoff, and approach flight conditions. The nonproprietary parts of the data obtained from experiments in 9- by 15-Foot Low-Speed Wind Tunnel (9?15 LSWT) tests were provided by NASA Glenn Research Center to perform the analyses. The tone and broadband noise components have been separated from raw test data by using a new data analysis tool. Results in terms of sound pressure levels, acoustic power levels, and their variations with rotor speed, angle of attack, thrust, and input shaft power have been presented and discussed. The effect of an upstream pylon on the noise levels of the model has been addressed. Empirical equations relating model's acoustic power level, thrust, and input shaft power have been developed. The far-field acoustic efficiency of the model is also determined for various simulated flight conditions. It is intended that the results presented in this work will serve as a database for comparison and improvement of other open rotor blade designs and also for validating open rotor noise prediction codes.

  5. All-fiber high-average power nanosecond-pulsed master-oscillator power amplifier at 2  μm with mJ-level pulse energy.

    Wang, Xiong; Jin, Xiaoxi; Zhou, Pu; Wang, Xiaolin; Xiao, Hu; Liu, Zejin

    2016-03-10

    We present a high-power nanosecond-pulsed Tm-doped fiber amplifier at 1.971 μm based on a master-oscillator power amplifier (MOPA) configuration. When the repetition rate is 500 kHz and the pulse width is 63.3 ns, the average power reaches 238 W, the peak power reaches 7.06 kW, and the pulse energy is 0.477 mJ. When the pulse train's repetition rate is 300 kHz with a pulse width of 63.7 ns, the average power reaches 197 W, the peak power reaches 9.73 kW, and the pulse energy is 0.66 mJ. When the pulse train's repetition rate is 200 kHz with a pulse width of 58.2 ns, the average power reaches 150 W, the peak power reaches 12.1 kW, and the pulse energy is 0.749 mJ. The spectral linewidths of the pulse trains are 0.15, 0.14, and 0.10 nm for 500 kHz repetition rate, 300 kHz repetition rate, and 200 kHz repetition rate, respectively. To the best of our knowledge, this is the first demonstration of high-power nanosecond-pulsed MOPA at 2 μm with the maximum average power reaching 238 W, the maximum peak power reaching 12.1 kW, and the maximum pulse energy reaching 0.749 mJ.

  6. Experimental Investigation of a Direct-drive Hall Thruster and Solar Array System at Power Levels up to 10 kW

    Snyder, John S.; Brophy, John R.; Hofer, Richard R.; Goebel, Dan M.; Katz, Ira

    2012-01-01

    As NASA considers future exploration missions, high-power solar-electric propulsion (SEP) plays a prominent role in achieving many mission goals. Studies of high-power SEP systems (i.e. tens to hundreds of kilowatts) suggest that significant mass savings may be realized by implementing a direct-drive power system, so NASA recently established the National Direct-Drive Testbed to examine technical issues identified by previous investigations. The testbed includes a 12-kW solar array and power control station designed to power single and multiple Hall thrusters over a wide range of voltages and currents. In this paper, single Hall thruster operation directly from solar array output at discharge voltages of 200 to 450 V and discharge powers of 1 to 10 kW is reported. Hall thruster control and operation is shown to be simple and no different than for operation on conventional power supplies. Thruster and power system electrical oscillations were investigated over a large range of operating conditions and with different filter capacitances. Thruster oscillations were the same as for conventional power supplies, did not adversely affect solar array operation, and were independent of filter capacitance from 8 to 80 ?F. Solar array current and voltage oscillations were very small compared to their mean values and showed a modest dependence on capacitor size. No instabilities or anomalous behavior were observed in the thruster or power system at any operating condition investigated, including near and at the array peak power point. Thruster startup using the anode propellant flow as the power 'switch' was shown to be simple and reliable with system transients mitigated by the proper selection of filter capacitance size. Shutdown via cutoff of propellant flow was also demonstrated. A simple electrical circuit model was developed and is shown to have good agreement with the experimental data.

  7. 地区电网交流送出断面调控研究%Application Research of Collaborative Stability Analysis Technology for Multi-level Power Grid in Yunnan Power Grid

    黄宋波; 朱余启; 杨浚文; 陈聪

    2014-01-01

    This paper focuses on the operation mode of Yunnan Power Grid after the 6 generators of Xiluodu Right-bank Power Plant being put into operation,and studies the control requirements of the AC sections of Northeast Yunnan Power Grid before and after the Xiluodu HVDC single pole being put into operation� Furthermore,this paper analyzes the power capacity distribution and com-pares the different regulating rates of power flow led by different power plants in Northeast Yunnan Power Grid� The simulation re-sults demonstrates that the regulation led by Xiluodu Right-bank Power Plant is effectively and timely capable of adjusting the power flow of the AC sending sections according to the load fluctuation and reduces the operation risk.%以2013年底溪洛渡右岸电厂6台机组投运后,溪洛渡直流单回双极投运前电网运行方式作为研究对象,研究了溪洛渡直流单极投运前后滇东北部电网交流送出断面控制要求,从多角度分析了滇东北部电网电源装机容量分布,对比了不同电厂主导滇东北部交流送出断面潮流时的调控速率,结果表明,由溪洛渡右岸电厂进行主导调控可根据负荷波动有效、及时调整滇东北部交流送出断面潮流,降低电网运行风险。

  8. Exploring the potential impact of implementing carbon capture technologies in fossil fuel power plants on regional European water stress index levels

    Schakel, W.B.; Pfister, Stephan; Ramirez, C.A.

    2015-01-01

    Equipping power plants with carbon capture technology can affect cooling demand and water use. This study has explored the potential impact of large scale deployment of power plants with carbon capture technologies on future regional water stress in Europe. A database including 458 of European large

  9. Loss and thermal redistributed modulation methods for three-level neutral-point-clamped wind power inverter undergoing Low Voltage Ride Through

    Ma, Ke; Blaabjerg, Frede

    2012-01-01

    investigates the loss and thermal performances of a 10 MW 3L-NPC wind power inverter undergoing Low Voltage Ride Through (LVRT) operation. A series of new space vector modulation methods are then proposed to relocate the thermal loading among the power switching devices. It is concluded that, with the proposed...

  10. 供电公司财务管理水平提升策略探讨%On the Strategies for Improving Financial Management Level of the Power Supply Company

    时小力

    2014-01-01

    供电公司中重要的环节就是财务管理,企业经营管理和公司财务管理水平高低有着直接的关系。本文将针对供电公司财务管理水平提升策略进行探讨。%The financial management is an important link in the power company, and business management has a direct relationship with financial management level of the enterprises. This article discusses the strategies for improving financial management level of the power supply company.

  11. Development of methods for evaluation of electricity saving and load levelling measures. Part 2: The planning and implementation of a power conservation campaign

    Storm Soerensen, M.; Madsen, P.K. [NESA A/S, Research and Development Dept. (Denmark)

    1997-12-01

    In recent years many campaigns and projects have been carried out with the purpose of reducing the energy consumption. Simultaneously a lot of economic and structural changes are taking place in society in general; changes which also affect the size of the electricity consumption. Furthermore, there is a trend towards increased use of wind mills and decentral combined heating and power plants, which affects the electricity load of the local area. It is difficult to identify and separate the effect of each of these attitude-adjusting activities. The project `Development of methods for evaluation of the effect of electricity saving and load levelling measures` focuses on two different methods which, on different levels, can be used to determine the impact of different different activities on the electricity consumption. Both methods are based on mathematical statistics, and they consist of an analysis of historical data and a test campaign which will make it possible to test specific activities in a comparatively small scale. The historical part covers the years 1974 to 1994 and include such variables as: demography, economic factors, climatic conditions, periods of electricity saving campaigns, the start of billing according to time of day tariff etc. The wish to be able to measure the extent of these energy saving and load reducing initiatives resulted in a test campaign which was carried out under very restricted conditions starting in the fall of 1996. If the effect of the test campaign can be measured and as a consequence of this a method can be estimated, it will be possible to place models which can measure the effect of future campaigns. The primary object of the campaign is not the size of the electricity savings of the individual customer, but rather to obtain total savings for the entire group of customers. The test has been structured in a way which makes it possible to perform an analysis of the effect of the campaign by use of analysis of intervention

  12. A Shift of Power

    2008-01-01

    Administrative reforms are shifting prefecture government powers to the county level in an effort to boost local economies on July 8, the government of China’s southernmost Hainan Province announced that it was to hand over 177 of its administrative powers to county-level governments. The move practically dismantled the powers of the

  13. A Power Efficient Exaflop Computer Design for Global Cloud System Resolving Climate Models.

    Wehner, M. F.; Oliker, L.; Shalf, J.

    2008-12-01

    Exascale computers would allow routine ensemble modeling of the global climate system at the cloud system resolving scale. Power and cost requirements of traditional architecture systems are likely to delay such capability for many years. We present an alternative route to the exascale using embedded processor technology to design a system optimized for ultra high resolution climate modeling. These power efficient processors, used in consumer electronic devices such as mobile phones, portable music players, cameras, etc., can be tailored to the specific needs of scientific computing. We project that a system capable of integrating a kilometer scale climate model a thousand times faster than real time could be designed and built in a five year time scale for US$75M with a power consumption of 3MW. This is cheaper, more power efficient and sooner than any other existing technology.

  14. New Driver For The Powerful Output Rf Amplifier Of Mmf Dtl Rf System

    Kvasha, A I; Vassilyev, A G

    2004-01-01

    More than 30 years ago a few powerful vacuum tubes were specially designed and produced in the former design office Swetlana for the Moscow meson factory DTL RF system. Among them was tetrode GI-51A with output pulse RF power up to 300 kW at frequency 198.2 MHz, which was used as driver for RF power amplifier with output RF pulse power (2-3) MW. In connection with well-known events in our country manufacture of these tubes, including GI-51A was finished about 10 years ago. In "SED-SPb" (successor of the design office Swetlana) triode GI-57A was offered instead of GI-51A. In this paper results of calculations and design of RF amplifier with new triode are presented. Preliminary results of RF amplifier tests, also presented in the paper, showed that triode GI-57A will be able successfully used in the DTL RF system channels.

  15. Converter Structure-Based Power Loss and Static Thermal Modeling of The Press-Pack IGBT Three-Level ANPC VSC Applied to Multi-MW Wind Turbines

    Senturk, Osman Selcuk; Helle, Lars; Munk-Nielsen, Stig

    2011-01-01

    MW wind turbine to a MV grid. The switching power loss models are built using the experimental switching power loss data acquired via the double-pulse tests conducted on a full-scale 3L-ANPC-VSC prototype. The converter static thermal model is developed based on the double-sided water-cooled press......-pack switches. Via a single-phase test setup with two full-scale 3L-ANPC-VSC legs, the developed power loss and thermal models are validated experimentally. Employing the validated models, the 3L-ANPC-VSC's thermal performance is demonstrated on simulation for a 6 MW wind turbine grid interface. Hence...

  16. 风电项目生态及电磁环境影响研究%Study of Ecological and Electromagnetic Influences on Wind Power Project

    张承芳; 陈众

    2014-01-01

    Taking Zhaoguan 48 .3MW wind power project of Hanshan County ,Anhui province as a case stud-y ,this article evaluatesthe environmental impacts of wind power project evaluation from the ecological and e-lectromagnetic aspects ,and puts forward the prevention measures .%以安徽含山昭关48.3M W风电项目工程为例,从生态和电磁两方面探讨了风电项目的环境影响评价,并提出了相应的防治措施。

  17. Comprehensive Benefit Evaluation of the Power Distribution Network Planning Project Based on Improved IAHP and Multi-Level Extension Assessment Method

    Qunli Wu; Chenyang Peng

    2016-01-01

    Reasonable distribution network planning is an essential prerequisite of the economics and security of the future power grid. The comprehensive benefit evaluation of a distribution network planning project can make significant contributions towards guiding decisions during the planning scheme, the optimization of the distribution network structure, and the rational use of resources. In this paper, in light of the characteristics of the power distribution network, the comprehensive benefit eva...

  18. Determination of optimal wind power acceptance level based approaching and Newton interpolation%基于逼近和牛顿插值法的最佳风电接纳水平确定

    林小雨; 江岳文; 温步瀛

    2015-01-01

    With the enlargement of the wind farm scale, the ability of accommodating wind powers of network becomes a main factor of wind farm planning. This paper makes a scheduling model comprehensively in consideration of operation cost of conventional units and wind curtailment with a wind power acceptance level parameter to determine the optimal level of wind power acceptance. And a wind power acceptance level optimization based particle swarm algorithm is proposed in the angle of the economical operation of conventional units and wind powers. This paper calculates in a system with one wind farm and 10 conventional units and works out the optimal level of wind power acceptance respectively of the 12 groups of typical output data. And then a comprehensive optimal acceptance level is determined using approaching method and Newton interpolation. The system is in an optimal economic operation at this level and proportion coefficient can be a reference of wind power planning.%随着风电场规模的不断扩大,电网接纳风电能力的限制已成为风电场规划的一个重要影响因素.为了确定系统接纳风电的最佳水平,建立了综合考虑常规机组运行成本和风电场弃风量的调度模型.引入风电接纳水平系数,从常规机组和风电场运行的经济性角度提出了一种基于粒子群算法的风电接纳水平的优化方法.对含1个风电场和10台常规机组的系统进行了计算分析.针对该风电场的12组典型出力数据分别优化得到对应的最佳风电接纳水平值并分别采用逼近法和牛顿插值法确定了系统的最佳接纳水平,在该水平下的风电出力可以使系统在一个最佳经济点运行.该比例系数可以作为风电场规划的参考.

  19. WKA 60 wind power plant for EW Helgoland

    Schwaiger, H.

    1988-01-01

    The authors demonstrate the wind power plant (0.8 to 1.3 MW range) to be built on the island of Helgoland, with its components (design and system diagrams) and a list of major technical characteristics. Details concern plant size, three-blade rotor, aerodynamically profiled rotor blades, rotor hub, rotor blade adjustment, electronic control of rotor blade drive, mechanical drive rod and turbine housing, rotor shaft and bearing, rotor brake, fixing device, spiral-toothing coupling, gear, generator shaft drive, dynamic concept and construction type of tower (50 m height, cylindrical shaft, conical base), tower basement, wind tracking system, electronics system, control and operation management, lifting and hoisting systems, assembly and maintenance concept. (HWJ).

  20. Offshore Wind Power Data

    Cutululis, Nicolaos Antonio; Litong-Palima, Marisciel; Zeni, Lorenzo;

    2012-01-01

    , the approach used in the TradeWind project has been used. This approach considered a first aggregation level for wind power at a grid node, and then a second aggregation at wind power regions. With this approach, wind power for a country can be expressed in one or several wind power nodes and one or several...... wind power regions. For onshore wind power, the estimated installed capacity was upscaled to meet the number published by EWEA in the Pure Power report. Wind speed time series were extracted from the WRF dataset available at DTU Wind Energy and interpolated to the exact location of the wind power......Wind power development scenarios are critical when trying to assess the impact of the demonstration at national and European level. The work described in this report had several objectives. The main objective was to prepare and deliver the proper input necessary for assessing the impact of Demo 4...

  1. Picosecond laser with 11 W output power at 1342 nm based on composite multiple doping level Nd:YVO4 crystal

    Rodin, Aleksej M.; Grishin, Mikhail; Michailovas, Andrejus

    2016-01-01

    We report results of design and optimization of high average output power picosecond and nanosecond laser operating at 1342 nm wavelength. Developed for selective micromachining, this DPSS laser is comprised of master oscillator, regenerative amplifier and output pulse control module. Passively mode-locked by means of semiconductor saturable absorber mirror and pumped with 808 nm wavelength Nd:YVO4 master oscillator emits 12.5 ps pulses at repetition rate of 55 MHz with average output power of ∼100 mW. The four-pass confocal delay line forms a longest part of the oscillator cavity in order to suppress thermo-mechanical misalignment. Picked from the train seed pulses were injected to the cavity of regenerative amplifier based on composite Nd:YVO4 crystal with diffusion-bonded segments of multiple Nd doping concentration end-pumped at 880 nm wavelength. Laser produces pulses of ∼13 ps duration at 300 kHz repetition rate with average output power of 11 W and nearly diffraction limited beam quality of M2∼1.03. Attained high peak power ∼2.8 MW facilitates conversion to the 2nd, 3rd and 6th harmonics at 671 nm, 447 nm and 224 nm wavelengths with 80%, 50% and 15% efficiency respectively. Without seeding the regenerative amplifier transforms to electro-optically cavity-dumped Q-switched laser providing 10 ns output pulses at high repetition rates with beam propagation factor of M2∼1.06.

  2. Combined application of sub-toxic level of silver nanoparticles with low powers of 2450 MHz microwave radiation lead to kill Escherichia coli in a short time

    Bardia Varastehmoradi

    2013-09-01

    Full Text Available   Objective(s: Electromagnetic radiations which have lethal effects on the living cells are currently also considered as a disinfective physical agent.   Materials and Methods: In this investigation, silver nanoparticles were applied to enhance the lethal action of low powers (100 and 180 W of 2450 MHZ electromagnetic radiation especially against Escherichia coli ATCC 8739. Silver nanoparticles were biologically prepared and used for next experiments. Sterile normal saline solution was prepared and supplemented by silver nanoparticles to reach the sub-inhibitory concentration (6.25 μg/mL. Such diluted silver colloid as well as free-silver nanoparticles solution was inoculated along with test microorganisms, particularly E. coli. These suspensions were separately treated by 2450 MHz electromagnetic radiation for different time intervals in a microwave oven operated at low powers (100 W and 180 W. The viable counts of bacteria before and after each radiation time were determined by colony-forming unit (CFU method. Results: Results showed that the addition of silver nanoparticles significantly decreased the required radiation time to kill vegetative forms of microorganisms. However, these nanoparticles had no combined effect with low power electromagnetic radiation when used against Bacillus subtilis spores. Conclusion: The cumulative effect of silver nanoparticles and low powers electromagnetic radiation may be useful in medical centers to reduce contamination in polluted derange and liquid wastes materials and some devices.

  3. The factor analysis of nuclear power plant in levelling off%核电厂四通一平要点分析

    王栋

    2014-01-01

    简要分析了四通一平阶段对核电站建设工期的影响,并采用理论联系实际的方法,对四通一平的土石方计算、边坡砌护及道路修建三个要点进行了详细阐述,为今后核电站的建设提供了参考借鉴。%The paper briefly analyzes impact of direct shipping links an even upon nuclear power station during its construction period,applies theory combining with practice method,and describes three points of earthwork calculation,slope masonry and road maintenance of direct ship-ping links an even,which has provided some guidance for nuclear power station construction.

  4. Automatic chemical monitoring in the composition of functions performed by the unit level control system in the new projects of nuclear power plant units

    Denisova, L. G.; Khrennikov, N. N.

    2014-08-01

    The article presents information on the state of regulatory framework and development of a subsystem for automated chemical monitoring of water chemistries in the primary and secondary coolant circuits used as part of the automatic process control system in new projects of VVER reactor-based nuclear power plant units. For the strategy of developing and putting in use the water chemistry-related part of the automated process control system within the standard AES-2006 nuclear power plant project to be implemented, it is necessary to develop regulatory documents dealing with certain requirements imposed on automatic water chemistry monitoring systems in accordance with the requirements of federal codes and regulations in the field of using atomic energy.

  5. Cost basis for hydroelectric power plants. Price level of 01.01.1995; Kostnadsgrunnlag for vannkraftanlegg. Prisnivaa pr 01.01.1995

    Stensby, H.; Slapgaard, J.

    1995-08-01

    This publication provides a basis for calculation of expected average construction costs and equipment costs for large hydroelectric power plants in Norway. The publication is not intended to be a tool for projecting with regard to optimization or choice of construction types, but should be useful at an early stage of planning. There is a supplementary publication (Publication no. 20/1995) for small plants. 80 figs., 12 tabs.

  6. SEB circuit-level model in N-channel power MOSFETs; Modele pour circuits du burnout dans des MOSFETs de puissance de type N

    Liu, J.; Schrimpf, R.D.; Massengill, L.; Galloway, K.F. [Vanderbilt Univ., Nashville, TN (United States)

    1999-07-01

    A Single Event Burnout (SEB) circuit model has been developed. The dependence of SEB sensitivity on various parameters is presented and compared with experimental results. The parasitic resistance and capacitance of the device as well as the circuit parameters contribute to the length of SEB pulse. Increasing the switching frequency of the power MOSFET may be a possible way to prevent SEB in applications. (authors)

  7. Development of a kilowatt-class, joule-level ultrafast laser for driving compact high average power coherent EUV/soft x-ray sources

    Reagan, Brendan A.; Baumgarten, Cory M.; Pedicone, Michael A.; Bravo, Herman; Yin, Liang; Woolston, Mark; Wang, Hanchen; Menoni, Carmen S.; Rocca, Jorge J.

    2016-03-01

    Our recent progress in the development of high energy / high average power, chirped pulse amplification laser systems based on diode-pumped, cryogenically-cooled Yb:YAG amplifiers is discussed, including the demonstration of a laser that produces 1 Joule, sub-10 picosecond duration, λ = 1.03μm pulses at 500 Hz repetition rate. This compact, all-diodepumped laser combines a mode-locked Yb:KYW oscillator and a water-cooled Yb:YAG preamplifer with two cryogenic power amplification stages to produce 1.5 Joule pulses with high beam quality which are subsequently compressed. This laser system occupies an optical table area of less than 1.5x3m2. This laser was employed to pump plasma-based soft x-ray lasers at λ = 10-20nm at repetition rates >=100 Hz. To accomplish this, temporally-shaped pulses were focused at grazing incidence into a high aspect ratio line focus using cylindrical optics on a high shot capacity rotating metal target. This results in an elongated plasma amplifier that produces microjoule pulses at several narrow-linewidth EUV wavelengths between λ = 109Å and 189Å. The resulting fraction of a milliwatt average powers are the highest reported to date for a compact, coherent source operating at these wavelengths, to the best of our knowledge.

  8. (134)Cs and ¹³⁷Cs levels in a grassland, 32 km northwest of the Fukushima 1 Nuclear Power Plant, measured for two seasons after the fallout.

    Terashima, Ichiro; Shiyomi, Masae; Fukuda, Hiroo

    2014-01-01

    We measured the levels of radioactive caesium (RACs; ¹³⁴Cs and ¹³⁷Cs) in plants and soil in a grassland, 32 km northwest of the Fukushima 1 Nuclear Power Plant, from June 2011 to October 2012. In 2011, the highest RACs levels (¹³⁴Cs + ¹³⁷Cs) in plants and in the 0-5 cm soil layer were approximately 80 kBq per kg dry weight (DW). Forage grasses and clovers in this grassland showed similar RACs levels. On a DW basis, the levels of RACs in these plants tended to increase with increasing biomass over both years, but the absolute levels decreased in 2012. The RACs levels in the soil decreased sharply with soil depth; the RACs level in the 5-10 cm soil layer was only 3 % of that in the 0-5 cm layer. The transfer factor (ratio of radioactivity in plant parts on DW basis to that in the 0-10 cm soil layer) was 0.5 and 1.0 for the aboveground and belowground plant parts, respectively, in 2011, and these values decreased by approximately 50 % in 2012. We discuss the possible mechanisms underlying these trends, and strategies to decrease the level of RACs in plants to the permissible level for forage.

  9. Statement by the Federal Government: Treatment of low and intermediate level radioactive wastes from nuclear power plants with regard to the irregularities disclosed in the Transnuklear GmbH

    Toepfer, K.

    1988-03-02

    The Federal Government sees three major tasks to be done after inquiries have shown that irregularities disclosed in the Transnuklear business also include some relating to nuclear safety: (1) Initiate investigation of possible hazards to man or the environment, and into events and scope of events in order to provide full information. (2) Immediate consequences with regard to the treatment of low and intermediate level radioactive waste from nuclear power plant, and state supervision thereof. (3) Investigate possible consequences with regard to nuclear waste management in the FRG. The Federal Government has taken immediate action on all three levels. (orig./HSCH).

  10. 新能源并网三电平逆变器中低功率区间效率优化%Efficiency Optimization in Low and Medium Power Range of New Energy Grid-connected Three-level Inverter

    王菲; 王勇; 傅旻帆

    2014-01-01

    三电平逆变器因为电压应力只有两电平逆变器的一半,并且具有损耗小、谐波含量低的特点,所以在风能、太阳能等新能源发电系统中得到了越来越多的应用和研究。文中从新能源的功率随机波动特点出发,首先,评估了应用于新能源系统的传统三电平逆变器拓扑的损耗特点,然后,针对应用于光伏发电系统的三电平并网逆变器提出了硬件和控制策略上的改进,最后,利用一台样机验证了所提出的改进措施。试验证明,所提改进措施能够有效改善和提高三电平逆变器的效率,尤其是在中低功率范围内的效率。%By virtue of its remarkably low voltage stress,low harmonics and low power loss,the three-level inverter is increasingly applied in renewable energy systems such as the solar and wind power system.Anyway,the manifest feature of the new energy generating system is power fluctuation.Proceeding from the stochastic power fluctuation,the conventional three-level inverter is evaluated in terms of its topological power loss first.Then,some new schemes of hardware and control strategies are proposed for a three-level inverter applied in a solar inverter. Finally, a prototype is built to verify the improvement.Test results show the proposed schemes can improve the efficiency of the three-level inverter,especially the efficiency in the low and medium power range.

  11. Recommendation of maximum allowable noise levels for offshore wind power systems; Empfehlung von Laermschutzwerten bei der Errichtung von Offshore-Windenergieanlagen (OWEA)

    Werner, Stefanie [Umweltbundesamt, Dessau-Rosslau (Germany). Fachgebiet II 2.3

    2011-05-15

    When offshore wind farms are constructed, every single pile is hammered into the sediment by a hydraulic hammer. Noise levels at Horns Reef wind farm were in the range of 235 dB. The noise may cause damage to the auditory system of marine mammals. The Federal Environmental Office therefore recommends the definition of maximum permissible noise levels. Further, care should be taken that no marine mammals are found in the immediate vicinity of the construction site. (AKB)

  12. Stochastic power system operation

    Power, Michael

    2010-01-01

    This paper outlines how to economically and reliably operate a power system with high levels of renewable generation which are stochastic in nature. It outlines the challenges for system operators, and suggests tools and methods for meeting this challenge, which is one of the most fundamental since large scale power networks were instituted. The Ireland power system, due to its nature and level of renewable generation, is considered as an example in this paper.

  13. Comparison of arsenic levels in fingernails with urinary As species as biomarkers of arsenic exposure in residents living close to a coal-burning power plant in Prievidza District, Slovakia

    Wilhelm, M.; Pesch, B.; Wittsiepe, R.; Jakubis, P.; Miskovic, P.; Keegan, T.; Nieuwenhuijsen, M.J.; Ranft, U. [Ruhr University of Bochum, Bochum (Germany)

    2005-01-01

    The associations between As levels in fingernails with both As concentrations in urine and environmental samples are reported. The participants (aged 20 - 80 years, mean 66 years) lived in the vicinity of a coal-burning power plant with high As emissions in the Prievidza District, Slovakia. Samples were taken in 1999 and 2000. The As levels in fingernails (n = 524) were measured after washing and digestion with microwave heating by hydride generation atomic absorption spectrometry. The spot urine samples (n = 436) were speciated for inorganic As (As{sub inorg}), monomethylarsonic (MMA) and dimethylarsinic acid (DMA) by hydride-cryogenic trap-atomic absorption spectrometry. The geometric mean As level in fingernails was 0.10 {mu}g/g (range, {lt}0.01-2.94 {mu}g/g). There was a clear association between As in fingernails and the distance of the home to the power plant (P {lt}0.001). The association between the distance to the power plant and total urinary As (As{sub sum}) (n = 436, no fish consumption during the last 3 days before sample collection) was less pronounced (P = 0.018). The As levels in fingernails were positively correlated to As in soil (n = 207, r = 0.23, P{lt}0.001) and to As in house dust (n = 209, r = 0.30, P{lt}0.001). The associations between urinary As{sub sum} and As concentrations in soil (n = 159, r = 0.13, P{lt}0.105) and in house dust (n = 162, r = 0.14, P{lt}0.081) were quite similar. It is concluded that As levels in fingernails are a reliable marker of environmental As exposure, and that As concentrations in fingernails reflect the As exposure in a similar manner compared with urinary As-sum and As species.

  14. Checking Power:An Argument from the Point of View of Utilitarianism-The Analysis of County-levelPower Lists”%控制权力:一个功利主义视角--县政“权力清单”辨析

    周庆智

    2014-01-01

    目前我国县级政府推行“权力清单”的目的是要控制和规范政府的行政权力,目标是适应市场经济发展和社会多样性变化而控制和约束权力的越界和不当行为,从而把政府与市场、政府与社会的关系确立在法治基础之上。“权力清单”的规范涉及中央与地方分权、政府职能转变、治理法治化等问题。然而,控制和规范政府权力,不仅涉及权力的结构性问题,更涉及权力的本质规定问题。县政“权力清单”的出台是在不触动基本权力结构的前提下做出的,也就是说,“权力清单”只是政府功能性权力的范围和职责的调整。规范县政权力必须在基本政治框架内和权力结构上做出制度性的调整和结构性的调适,不然,“权力清单制度”的推展不可能达到控制和规范政府行政权力的目标,只能是政府“自己规范自己权力”的单方面举措而已。%The purpose of carrying out “power lists”policy is to control and standardize the administration power of government so that the transgressing and improper behaviors of government can be placed under control and checked with development of market economy and diversification of society.The essence of all of that is to base the relationship between government and market,between government and society on the foundation of rule of law.Standardizing“power lists”involves the issues of separating power between central government and local government,functional transition of government,and the process of rule of law.However,not only does con-trolling and standardizing power involve the problem of power structure,but also involves the essential standard of power.The precondition of county-levelpower lists”is intended not to touch the basic power structure.In other words,“power lists”is j ust adj usting scope and duty of functional power of government,and standardizing county-level government

  15. FINAL REPORT – CHARACTERIZATION SURVEY OF THE SPRU LOWER LEVEL HILLSIDE AREA AT THE KNOLLS ATOMIC POWER LABORATORY, NISKAYUNA, NEW YORK DCN 5146-SR-01-0

    Evan Harpenau

    2011-08-29

    The Separations Process Research Unit (SPRU) is located within the boundary of Knolls Atomic Power Laboratory (KAPL) at 2425 River Road, Niskayuna, Schenectady County, New York (Figure A-1). SPRU was designed and developed to research an efficient process to chemically separate plutonium and uranium from processed fuel. Buildings H2 and G2 were the primary research and process facilities. SPRU operated between February 1950 and October 1953 at which time the research was successful in developing useable reduction oxidation and plutonium uranium extraction processes. These processes were subsequently moved to the Hanford and the Savannah River sites for full-scale operations. Building H2 was used by KAPL after the SPRU process ceased until the late 1990s for radioactive wastewater processing and Building G2 was utilized for offices. Process areas and equipment were maintained in a safe condition under a surveillance and maintenance program.

  16. Autler-Townes splitting via frequency upconversion at ultra-low power levels in cold $^{87}$Rb atoms using an optical nanofiber

    Kumar, Ravi; Deasy, Kieran; Chormaic, Síle Nic

    2015-01-01

    The tight confinement of the evanescent light field around the waist of an optical nanofiber makes it a suitable tool for studying nonlinear optics in atomic media. Here, we use an optical nanofiber embedded in a cloud of laser-cooled 87Rb for near-infrared frequency upconversion via a resonant two-photon process. Sub-nW powers of the two-photon beams, at 780 nm and 776 nm, co-propagate through the optical nanofiber and generation of 420 nm photons is observed. A measurement of the Autler-Townes splitting provides a direct measurement of the Rabi frequency of the 780 nm transition. Through this method, dephasings of the system can be studied. In this work, the optical nanofiber is used as an excitation and detection tool simultaneously, and it highlights some of the advantages of using fully fibered systems for nonlinear optics with atoms.

  17. Autler-Townes splitting via frequency up-conversion at ultralow-power levels in cold 87Rb atoms using an optical nanofiber

    Kumar, Ravi; Gokhroo, Vandna; Deasy, Kieran; Chormaic, Síle Nic

    2015-05-01

    The tight confinement of the evanescent light field around the waist of an optical nanofiber makes it a suitable tool for studying nonlinear optics in atomic media. Here, we use an optical nanofiber embedded in a cloud of laser-cooled 87Rb for near-infrared frequency up-conversion via a resonant two-photon process. Sub-nW powers of the two-photon radiation, at 780 and 776 nm, copropagate through the optical nanofiber and the generation of 420 nm photons is observed. A measurement of the Autler-Townes splitting provides a direct measurement of the Rabi frequency of the 780 nm transition. Through this method, dephasings of the system can be studied. In this work, the optical nanofiber is used as an excitation and detection tool simultaneously, and it highlights some of the advantages of using fully fibered systems for nonlinear optics with atoms.

  18. Do force-time and power-time measures in a loaded jump squat differentiate between speed performance and playing level in elite and elite junior rugby union players?

    Hansen, Keir T; Cronin, John B; Pickering, Stuart L; Douglas, Lee

    2011-09-01

    The purpose of this study was to investigate the discriminative ability of rebound jump squat force-time and power-time measures in differentiating speed performance and competition level in elite and elite junior rugby union players. Forty professional rugby union players performed 3 rebound jump squats with an external load of 40 kg from which a number of force-time and power-time variables were acquired and analyzed. Additionally, players performed 3 sprints over 30 m with timing gates at 5, 10, and 30 m. Significant differences (p rugby union players; however, a number of force and power variables including peak force, PP, force at 100 milliseconds from minimum force, and force and impulse 200 milliseconds from minimum force were significantly (p rugby union players. For speed development in rugby union players, training strategies should aim to optimize the athlete's power to weight ratio, and lower body resistance training should focus on movement velocity. For player development to transition elite junior players to elite status, adding lean mass is likely to be most beneficial.

  19. Active and Reactive Power Control of a Doubly Fed Induction Generator

    Zerzouri Nora

    2014-10-01

    Full Text Available Wind turbine WT occupies gradually a large part in world energy market, Doubly fed induction generator DFIG is mostly used in WT, it allow highly flexible active and reactive power generation control. This paper presents dynamic modeling and simulation of a doubly fed induction generator based on grid-side and rotor-side converter control. The DFIG, grid-side converter, rotor-side converter, and its controllers are performed in MATLAB/Simulink software. Dynamic response in grid connected mode for variable speed wind operation is investigated. Simulation results on a 3 MW DFIG system are provided to demonstrate the effectiveness of the proposed control strategy during variations of active and reactive power, rotor speed, and converter dc link voltage.

  20. A comparative investigation of three PM-less MW power range wind generator topologies

    Bratiloveanu, Catalin-Rauti; Traian Cosmin Anghelus, Dumitru; Boldea, I.

    2012-01-01

    heteropolar-rotor (standard) synchronous generators, especially for direct drives (very low speed) and multibrid (with single stage transmission (5/1-8/1 ratio)), new topologies have to be investigated to reduce initial costs and weights for high enough efficiency and energy annual yield. The present paper......, with sensitivity design inquires, the claw pole synchronous generator topology for a multibrid wind generator of 3 MW ,75rpm generator for a 15 rpm wind turbine with above 94 % efficiency for unity power factor (diode rectified output) for around 10 tons of copper and iron core materials. Though the case studies...... refer to large wind generators the same topologies are believed worth considering for powers less than 1 MW and even less than 100 kW. Similar topologies may be applied to micro-hydro generators. The results are promising but further in depth modeling, design and control studies of such novel PM...

  1. Repeatable, accurate, and high speed multi-level programming of memristor 1T1R arrays for power efficient analog computing applications.

    Merced-Grafals, Emmanuelle J; Dávila, Noraica; Ge, Ning; Williams, R Stanley; Strachan, John Paul

    2016-09-09

    Beyond use as high density non-volatile memories, memristors have potential as synaptic components of neuromorphic systems. We investigated the suitability of tantalum oxide (TaOx) transistor-memristor (1T1R) arrays for such applications, particularly the ability to accurately, repeatedly, and rapidly reach arbitrary conductance states. Programming is performed by applying an adaptive pulsed algorithm that utilizes the transistor gate voltage to control the SET switching operation and increase programming speed of the 1T1R cells. We show the capability of programming 64 conductance levels with programming speed and programming error. The algorithm is also utilized to program 16 conductance levels on a population of cells in the 1T1R array showing robustness to cell-to-cell variability. In general, the proposed algorithm results in approximately 10× improvement in programming speed over standard algorithms that do not use the transistor gate to control memristor switching. In addition, after only two programming pulses (an initialization pulse followed by a programming pulse), the resulting conductance values are within 12% of the target values in all cases. Finally, endurance of more than 10(6) cycles is shown through open-loop (single pulses) programming across multiple conductance levels using the optimized gate voltage of the transistor. These results are relevant for applications that require high speed, accurate, and repeatable programming of the cells such as in neural networks and analog data processing.

  2. The Definition of the Village-level Public Power under the Background of the Vil lagers′ Self-governance%村民自治背景下的村级公共权力厘定

    郝炜

    2012-01-01

    村民自治背景下,基层社会治理发生了重大转变,以村级公共权力为视角进行观察,能够比较准确地反映这种转变。基于对制度文本及实践模式的研究,村级公共权力的基本内涵可以确定为,在中国共产党领导下的村级政治主体为实现村级公共利益进行民主选举、民主决策、民主管理、民主监督的法定权力。在这一基本内涵的基础上可以发现,村级公共权力的静态回路是一个多主体多层次的复杂体系,且其运行过程存在不同环节的发展不均衡和结果低效率的现象。%Under the background of villagers′ self-governance,grass-root society manageme nt has greatly changed.These changes can be accurately observed from the view o f the village-level public power.The village-level public power,based on the s tudy of the system text and practice mode,can be defined as the legal power of the political subjects at village-level in achieving their public interests unde r the leadership of the Chinese Communist Party,by way of democratic elections,democratic decision-making,democratic management and supervision.And on this basis the static structure of the village-level public power turns out to be a complex system of multi-level and multi-subject,unavoid of the phenomena of une ven development at different steps and low efficiency of results in its operatio n.

  3. 降低县级供电企业管理线损的方法%Effective Method for Reducing Line Loss of County Level Power Supply Enterprise

    刘俊恒

    2012-01-01

    Line loss management is the important content in the lean market management of power supply enterprise, which is directly related to an enterprisds business performance and economic benefit. For standardizing line loss management according to station, voltage, line, station area, it is proposed to start from detail management and extend the management to every links of the line loss, so as to achieve the goal of reducing line loss and improving the economic benefit of enterprise efficiency.%线损管理是供电企业营销精细化管理工作的重要内容,它直接关系到企业经营成果和经济效益。就如何规范线损管理中分站、分压、分线、分台区考核,并按“剥洋葱”法把管理工作延伸到与配网线损有关的每一个环节,从细节管理入手,最终达到降损增效、提高企业经济效益的目的。

  4. Comparison of Computational and Experimental Results for a Transonic Variable-speed Power-Turbine Blade Operating with Low Inlet Turbulence Levels

    Booth, David T.; Flegel, Ashlie B.

    2015-01-01

    A computational assessment of the aerodynamic performance of the midspan section of a variable-speed power-turbine blade is described. The computation comprises a periodic single blade that represents the 2-D Midspan section VSPT blade that was tested in the NASA Glenn Research Center Transonic Turbine Blade Cascade Facility. A commercial, off-the-shelf (COTS) software package, Pointwise and CFD++, was used for the grid generation and RANS and URANS computations. The CFD code, which offers flexibility in terms of turbulence and transition modeling options, was assessed in terms of blade loading, loss, and turning against test data from the transonic tunnel. Simulations were assessed at positive and negative incidence angles that represent the turbine cruise and take-off design conditions. The results indicate that the secondary flow induced at the positive incidence cruise condition results in a highly loaded case and transitional flow on the blade is observed. The negative incidence take-off condition is unloaded and the flow is very two-dimensional. The computational results demonstrate the predictive capability of the gridding technique and COTS software for a linear transonic turbine blade cascade with large incidence angle variation.

  5. Discussion on financial management of county's electric level power supply enterprise%县级供电企业财务管理探讨

    夏岚

    2012-01-01

    This paper proposed that county electric power supply enterprise must set up enterprise management to put management as the center, management in financial management as the core concept , and from promoting financial personnel service quality, strengthening the basis of accounting standard, implement the overall budget management system, financial informatization construction, establishing financial management index system, executing significant financial transaction report system and other aspects to strengthen financial management, and by these measures to reduce financial risk.%县级供电企业必须树立企业管理以经营管理为中心,经营管理以财务管理为核心的理念,从财务人员业务素质的提升、会计基础规范的加强、全面预算管理制度的贯彻、财务信息化建设、财务管理指标体系的建立、重大财务事项报告制度执行等多方面加强财务管理工作,降低财务风险。

  6. 永磁直驱风电机组的三电平升压变流技术%The technology of three-level boost converter based on direct-drive PMSG wind turbine generator system

    姚兴佳; 赵超群

    2013-01-01

    对于额定功率为2 MW或更高容量的变流器,背靠背(BTB)中点钳位型(NPC)变流器可以降低系统的成本、体积以及复杂性.文章提出一种新型拓扑结构,该结构采用二极管整流,三电平升压(TLB)和中点钳位型变流器,能够进一步降低系统的成本和体积.该结构在直流侧完成最大功率点跟踪(MPPT)控制计划,使TLB解决MPPT和直流侧电容平衡问题,为中点钳位控制提供更大的灵活性.最后以3 MW永磁风力发电系统为仿真对象,仿真结果验证了该拓扑结构和控制策略的正确性.%For power rating of 2 MW or higher, the back-to-back (BTB) neutral-point clamped (NPC) converters are most preferable choice for wind turbine manufacturers as its reduced cost, size and complexity of the system compared with the BTB two-level converters. In this paper, a new topology using diode rectifier, three-level boost (TLB) and NPC converter has been proposed to further reduce the cost and size. The DC-link maximum power point tracking (MPPT) control scheme has been proposed in which the TLB performs MPPT and balancing of DC-link capacitors, which provides a greater flexibility for NPC control. The simulation results for 3 MW PMSG wind energy system validate the proposed topology and control scheme.

  7. 岭澳核电站CFI系统雷达液位计的原理和操作%Ling ao nuclear power station CFI system the principle of radar level gauge and operations

    陈罡

    2015-01-01

    岭澳核电站CFI系统原使用超声波水位测量仪,总是因潮湿、天气及泡沫等因素的影响导致故障闪发,状态不是很稳定,所以将其改造为雷达式液位计。本文就岭澳核电站CFI系统的雷达式液位计的原理、特点和操作方法进行简要论述。%The CFI system of Ling Ao nuclear power station the original use of ultrasonic level measurement instrument is always affected by wet weather and other factors,the bubble causes the failure of flash,the state is not very stable,so its transformation for the radar level gauge.The principle, characteristic and operation method of this paper is the radar type level of Ling Ao Nuclear Power Station CFI system tester are briefly discussed.

  8. Multimegawatt space power reactors

    Dearien, J.A.; Whitbeck, J.F.

    1989-01-01

    In response to the need of the Strategic Defense Initiative (SDI) and long range space exploration and extra-terrestrial basing by the National Air and Space Administration (NASA), concepts for nuclear power systems in the multi-megawatt levels are being designed and evaluated. The requirements for these power systems are being driven primarily by the need to minimize weight and maximize safety and reliability. This paper will discuss the present requirements for space based advanced power systems, technological issues associated with the development of these advanced nuclear power systems, and some of the concepts proposed for generating large amounts of power in space. 31 figs.

  9. 现行输电塔设计规范可靠度水准的评估与分析%Evaluation and Analysis on Reliability Level of Current Design Specification for Power Transmission Tower

    王松涛; 高斐略; 李正良; 范文亮; 徐彬

    2015-01-01

    In order to make systematic and correct evaluation on reliability level of design specification for power transmission tower structure,relevant research on reliability of design expressions of different stress components of the power transmis-sion tower was developed based on DL/T 5 1 54-2002 technical regulations for structure design on overhead power transmis-sion line tower. Statistic parameters of loads and resistance of tower components and influencing laws were analyzed as well. Considering wind speed,structure importance factors and affect of wind load reappearing period,refined evaluation on reli-ability level of design expressions were made. In addition,reliability level of current specification for the tower in our coun-try was investigated.%为了对输电线路杆塔结构设计规范进行较为系统且准确的可靠水准评估,基于 DL/T 5154—2002《架空送电线路杆塔结构设计技术规定》,对输电塔不同受力构件设计表达式的可靠度展开相关研究,分析了杆塔构件荷载、抗力的统计参数及其影响规律。考虑风速、结构重要性系数及风荷载重现期的影响,对设计表达式的可靠度水平进行了精细化评估,考察了我国杆塔现行规范的可靠度水平。

  10. Repeatable, accurate, and high speed multi-level programming of memristor 1T1R arrays for power efficient analog computing applications

    Merced-Grafals, Emmanuelle J.; Dávila, Noraica; Ge, Ning; Williams, R. Stanley; Strachan, John Paul

    2016-09-01

    Beyond use as high density non-volatile memories, memristors have potential as synaptic components of neuromorphic systems. We investigated the suitability of tantalum oxide (TaOx) transistor-memristor (1T1R) arrays for such applications, particularly the ability to accurately, repeatedly, and rapidly reach arbitrary conductance states. Programming is performed by applying an adaptive pulsed algorithm that utilizes the transistor gate voltage to control the SET switching operation and increase programming speed of the 1T1R cells. We show the capability of programming 64 conductance levels with cells in the 1T1R array showing robustness to cell-to-cell variability. In general, the proposed algorithm results in approximately 10× improvement in programming speed over standard algorithms that do not use the transistor gate to control memristor switching. In addition, after only two programming pulses (an initialization pulse followed by a programming pulse), the resulting conductance values are within 12% of the target values in all cases. Finally, endurance of more than 106 cycles is shown through open-loop (single pulses) programming across multiple conductance levels using the optimized gate voltage of the transistor. These results are relevant for applications that require high speed, accurate, and repeatable programming of the cells such as in neural networks and analog data processing.

  11. Power Outages

    ... Thunderstorms & Lightning Tornadoes Tsunamis Volcanoes Wildfires Main Content Power Outages This page provides basic safety tips and ... during and after a power outage. Before a Power Outage Build or restock your emergency preparedness kit , ...

  12. Pragmatic power

    Eccles, William

    2008-01-01

    Pragmatic Power is focused on just three aspects of the AC electrical power system that supplies and moves the vast majority of electrical energy nearly everywhere in the world: three-phase power systems, transformers, and induction motors. The reader needs to have had an introduction to electrical circuits and AC power, although the text begins with a review of the basics of AC power. Balanced three-phase systems are studied by developing their single-phase equivalents. The study includes a look at how the cost of ""power"" is affected by reactive power and power factor. Transformers are cons

  13. Direct FuelCell/Turbine Power Plant

    Hossein Ghezel-Ayagh

    2008-09-30

    major achievement by successfully completing 8000 hours of operation at the Billings site. The Alpha sub-MW DFC/T power plant unit was returned to the factory for post-operation inspection and analysis. The success of the Alpha Unit operation in the field and achievement of the ultra-high efficiency of 58%, triggered the establishment of a MW-scale commercial product design and development program. Design of a 3 MW (nominal rating) DFC/T Power Plant was completed with an electrical efficiency approaching 60+% LHV of natural gas depending on the design and performance of the gas turbine. Development efforts incorporated lessons learned from the Alpha sub-MW DFC/T power plant demonstration, as well as design features from FCE's commercial product offerings, the DFC1500 and DFC3000 MW-class simple cycle power plants. The 3 MW DFC/T power plant is anticipated to be a superb alternative for large distributed generation applications in locations with high cost-of-electricity.

  14. Avian radioecology on a nuclear power station site. Final report. Occurrence and effects of chronic, low-level oil contamination in a population of sooty terns (Sterna fuscata)

    Robertson, M.J.

    1978-07-05

    Records from 45,219 Sooty Terns (Sterna fuscata) captured for banding and examined for presence of oil on plumage were assessed for occurrence and effects of chronic, low-level oil contamination. Occurrence of oiled plumage averaged 2.6% for all years between 1962 and 1977, and ranged from 0.2% to 12.0% within years. Incidence of oiling increased significantly from the 1960's to the 1970's, and was far higher in 1970 than any other year. Oil was most frequently found on posterior, ventral plumage suggesting contact is made when Sooty Terns dip to the sea surface when foraging. A paired comparison shows that return rates were not significantly different between birds with and without detectable oil on plumage. Weights of oiled birds did not differ from controls, and no demonstrable effect of oiling on nesting was found. Sooty Terns are less susceptible to oil pollution than most other seabirds. Food is caught at or above the surface by contact dipping, and landing on the water is rare. (The report contains nothing about radioecology).

  15. A CMOS Low Power PLL Designed in Transistor Level with Transmission Gate VCO and Dynamic PFD%用传输门VCO和动态PFD设计低功耗CMOS琐相环

    袁寿财; 郑月明

    2005-01-01

    To realize the high speed and low power CMOS PLL(Phase Locked Loop), the new circuits of VCO and PFD is designed in transistor level. In the VCO, the high speed and low power is realized using transmission-gate(TG) with an adaptive delay cell and low supply sensitivity. This delay cell has a built-in compensation circuit that senses and corrects the delay variation caused by supply fluctuation. And in the PFD, low power and small chip area is realized with the dynamic inverter. A fully CMOS PLL using these components has been designed based 0.6 μm CMOS technology and its SPICE model. SPICE simulation results show that at 2.5V supply voltage, the designed PLL can operate over 1000 MHz and dissipate power less than 50mW.%锁相环(PLL)是VLSI系统的重要单元电路之一,为了实现高速低功耗的CMOS锁相环,用传输门VCO和动态反相器PFD电路设计CMOS锁相环.传输门结构VCO具有高速、低电压和低功耗的特性,而动态反相器PFD具有功耗低和面积小的特点.SPICE模拟表明,当电源电压为2.5 V时,基于0.6 μm CMOS工艺设计的CMOS锁相环电路,工作频率高达1000 MHz,而功耗低于50mW.

  16. 新疆部分燃煤和电厂粉煤灰中天然放射性水平分析%The Natural Radioactive Level of the Coal, Coal Cinder and Slag from Power Plants

    谢贵英; 艾尔肯·阿不列木; 艾克拜尔·吐合提

    2011-01-01

    采用低本底γ能谱仪对乌鲁木齐、伊犁和哈密地区的煤以及华电厂和国电厂的粉煤灰中的天然放射性核素含量进行了测量.测量结果:226Ra、232Th、40K含量按样品个数的加权平均值,乌鲁木齐煤为5.54、3.51、69.15 Bq/kg;伊犁煤为9.59、4.02、72.95 Bq/kg;哈密煤为7.42、4.87、88.32 Bq/kg;华电厂粉煤灰中为29.31、15.57、111.39 Bq/kg;国电厂粉煤灰中为24.67、16.22、133.98 Bq/kg.并依据国家标准对粉煤灰进行分类,结果表明,粉煤灰的使用不受限制.%The - ray spectrometer was used to analyze the natural radioactive level of the coal from Urumqi, Yi li and Ha mi areas; coal cinder and slag from China power plant and state power plant in Urumqi. The average value of ,,and of coal is 5. 54、 3. 51、69. 15 from Urumqi; 9. 59、4. 02,72. 95from Yi li;7. 42、4. 87、88. 32from Ha mi;the coal cinder is 29. 31、15. 57、111. 39 from China power plant; 24. 67、16. 22、133. 98 from state power plant, respectively. The result reveals that the coal cinder' s application range has no limit according to national standard.

  17. Electric power annual 1993

    1994-12-08

    This report presents a summary of electric power industry statistics at national, regional, and state levels: generating capability and additions, net generation, fossil-fuel statistics, retail sales and revenue, finanical statistics, environmental statistics, power transactions, demand side management, nonutility power producers. Purpose is to provide industry decisionmakers, government policymakers, analysts, and the public with historical data that may be used in understanding US electricity markets.

  18. 县级供电企业业务扩充管理优化策略%Business expansion management optimization strategy at the county level power supply enterprises

    周文伟

    2013-01-01

    The article analyzed the working process of busi-ness expansion management at county power supply enterprise at present. In order to shorten the customer connect cable with time and improve customer satisfaction, the short board optimization is made. Plane collaboration mechanism at county company level and point-to-point sunshine business expansion management system at power substation level is established. Finally it realized the eco-nomic and social benefits of the steady climb and electricity“gov-ernment trust, customer satisfaction”.%通过对目前县级供电企业业扩工作流程的分析,以缩短客户接电报装时限、提升客户满意度为目标,打造县公司层面的平面协作机制和供电所层面的点对点的阳光业扩管理体系,最终实现售电量稳步攀升和“政府放心,客户满意”的经济、社会效益的双丰收。

  19. A Bayesian framework to account for complex non-genetic factors in gene expression levels greatly increases power in eQTL studies.

    Oliver Stegle

    2010-05-01

    Full Text Available Gene expression measurements are influenced by a wide range of factors, such as the state of the cell, experimental conditions and variants in the sequence of regulatory regions. To understand the effect of a variable of interest, such as the genotype of a locus, it is important to account for variation that is due to confounding causes. Here, we present VBQTL, a probabilistic approach for mapping expression quantitative trait loci (eQTLs that jointly models contributions from genotype as well as known and hidden confounding factors. VBQTL is implemented within an efficient and flexible inference framework, making it fast and tractable on large-scale problems. We compare the performance of VBQTL with alternative methods for dealing with confounding variability on eQTL mapping datasets from simulations, yeast, mouse, and human. Employing Bayesian complexity control and joint modelling is shown to result in more precise estimates of the contribution of different confounding factors resulting in additional associations to measured transcript levels compared to alternative approaches. We present a threefold larger collection of cis eQTLs than previously found in a whole-genome eQTL scan of an outbred human population. Altogether, 27% of the tested probes show a significant genetic association in cis, and we validate that the additional eQTLs are likely to be real by replicating them in different sets of individuals. Our method is the next step in the analysis of high-dimensional phenotype data, and its application has revealed insights into genetic regulation of gene expression by demonstrating more abundant cis-acting eQTLs in human than previously shown. Our software is freely available online at http://www.sanger.ac.uk/resources/software/peer/.

  20. High field NMR spectroscopy and FTICR mass spectrometry: powerful discovery tools for the molecular level characterization of marine dissolved organic matter from the South Atlantic Ocean

    Hertkorn, N.; Harir, M.; Koch, B. P.; Michalke, B.; Grill, P.; Schmitt-Kopplin, P.

    2012-01-01

    Non target high resolution organic structural spectroscopy of marine dissolved organic matter (DOM) isolated on 27 November 2008 by means of solid phase extraction (SPE) from four different depths in the South Atlantic Ocean off the Angola coast (3.1° E; -17.7° S; Angola basin) provided molecular level information of complex unknowns with unprecedented coverage and resolution. The sampling was intended to represent major characteristic oceanic regimes of general significance: 5 m (FISH; near surface photic zone), 48 m (FMAX; fluorescence maximum), 200 m (upper mesopelagic zone) and 5446 m (30 m above ground). 800 MHz proton (1H) nuclear magnetic resonance (NMR) 1H NMR, spectra were least affected by fast and differential transverse NMR relaxation and produced at first similar looking, rather smooth bulk NMR envelopes reflecting intrinsic averaging from massive signal overlap. Visibly resolved NMR signatures were most abundant in surface DOM but contributed at most a few percent to the total 1H NMR integral and were mainly limited to unsaturated and singly oxygenated carbon chemical environments. The relative abundance and variance of resolved signatures between samples was maximal in the aromatic region; in particular, the aromatic resolved NMR signature of the deep ocean sample at 5446 m was considerably different from that of all other samples. When scaled to equal total NMR integral, 1H NMR spectra of the four marine DOM samples revealed considerable variance in abundance for all major chemical environments across the entire range of chemical shift. Abundance of singly oxygenated CH units and acetate derivatives declined from surface to depth whereas aliphatics and carboxyl-rich alicyclic molecules (CRAM) derived molecules increased in abundance. Surface DOM contained a remarkably lesser abundance of methyl esters than all other marine DOM, likely a consequence of photodegradation from direct exposure to sunlight. All DOM showed similar overall 13C NMR

  1. Wireless Power Transmission for Power Supply: State of Art

    2011-01-01

    The wireless power supply is motivated by simple and comfortable use of many small electric appliances with low power input. This paper reviews the concepts which are suitable for wireless power transmission with respect to power supply of such appliances in small areas. The categorization of the concepts is made. The efficiency of the concepts is discussed on general base. The reference levels for exposure to electric and magnetic fields are mentioned, and maximal power delivered to an appli...

  2. Influence of System Inertia Time Constants on Transient Stability Level of Interconnected AC Power Grid%系统惯性时间常数对互联电网暂态稳定水平的影响

    赵振元; 陈维荣; 戴朝华; 张雪霞

    2012-01-01

    由于区域电网的互联,整个系统的惯性时间常数将会发生明显变化,继而会影响整网的暂态稳定水平。基于暂态能量函数法,通过对等值2机系统进行数学推导并作暂态稳定分析,研究了系统在各种运行方式下,2端机组惯量变化对电力系统暂态稳定水平产生的影响,比较了两端机组惯量变化分别对系统暂态稳定性的影响,并发现了系统机组惯性时间常数对系统暂态稳定水平造成的影响与系统的负荷水平及初始工况有关。在理论分析的基础上,结合相关算例在各种运行方式下进行了仿真研究,仿真结果验证了分析结果的正确性。%Due to the interconnection of regional power grids, the inertia time constant of the whole interconnected grid evidently changes, then transient stability level of the interconnected power grid will be influenced. Based on transient energy function, by means of mathematical deduce for equivalent two-machine system and analysis on its transient stability, the influences of unit inertial changes at both terminals on transient stability level of the whole system under various operation modes are researched, and respective influences of terminal unit inertial changes on transient stability of the whole grid are compared, besides, it is found that the influences of unit inertial time constants on system transient stability level are relevant to load level and initial operating condition of the power grid. Based on theoretical analysis, simulation of concerned examples under various operation modes is performed and the correctness of theoretical analysis results is verified by simulation results.

  3. High field NMR spectroscopy and FTICR mass spectrometry: powerful discovery tools for the molecular level characterization of marine dissolved organic matter from the South Atlantic Ocean

    N. Hertkorn

    2012-01-01

    Full Text Available Non target high resolution organic structural spectroscopy of marine dissolved organic matter (DOM isolated on 27 November 2008 by means of solid phase extraction (SPE from four different depths in the South Atlantic Ocean off the Angola coast (3.1° E; −17.7° S; Angola basin provided molecular level information of complex unknowns with unprecedented coverage and resolution. The sampling was intended to represent major characteristic oceanic regimes of general significance: 5 m (FISH; near surface photic zone, 48 m (FMAX; fluorescence maximum, 200 m (upper mesopelagic zone and 5446 m (30 m above ground.

    800 MHz proton (1H nuclear magnetic resonance (NMR 1H NMR, spectra were least affected by fast and differential transverse NMR relaxation and produced at first similar looking, rather smooth bulk NMR envelopes reflecting intrinsic averaging from massive signal overlap. Visibly resolved NMR signatures were most abundant in surface DOM but contributed at most a few percent to the total 1H NMR integral and were mainly limited to unsaturated and singly oxygenated carbon chemical environments. The relative abundance and variance of resolved signatures between samples was maximal in the aromatic region; in particular, the aromatic resolved NMR signature of the deep ocean sample at 5446 m was considerably different from that of all other samples. When scaled to equal total NMR integral, 1H NMR spectra of the four marine DOM samples revealed considerable variance in abundance for all major chemical environments across the entire range of chemical shift. Abundance of singly oxygenated CH units and acetate derivatives declined from surface to depth whereas aliphatics and carboxyl-rich alicyclic molecules (CRAM derived molecules increased in abundance. Surface DOM contained a remarkably lesser abundance of methyl esters than all other marine DOM, likely a consequence of photodegradation from direct

  4. High-field NMR spectroscopy and FTICR mass spectrometry: powerful discovery tools for the molecular level characterization of marine dissolved organic matter

    Hertkorn, N.; Harir, M.; Koch, B. P.; Michalke, B.; Schmitt-Kopplin, P.

    2013-03-01

    High-performance, non-target, high-resolution organic structural spectroscopy was applied to solid phase extracted marine dissolved organic matter (SPE-DOM) isolated from four different depths in the open South Atlantic Ocean off the Angola coast (3° E, 18° S; Angola Basin) and provided molecular level information with extraordinary coverage and resolution. Sampling was performed at depths of 5 m (Angola Current; near-surface photic zone), 48 m (Angola Current; fluorescence maximum), 200 m (still above Antarctic Intermediate Water, AAIW; upper mesopelagic zone) and 5446 m (North Atlantic Deep Water, NADW; abyssopelagic, ~30 m above seafloor) and produced SPE-DOM with near 40% carbon yield and beneficial nuclear magnetic resonance (NMR) relaxation properties, a crucial prerequisite for the acquisition of NMR spectra with excellent resolution. 1H and 13C NMR spectra of all four marine SPE-DOM showed smooth bulk envelopes, reflecting intrinsic averaging from massive signal overlap, with a few percent of visibly resolved signatures and variable abundances for all major chemical environments. The abundance of singly oxygenated aliphatics and acetate derivatives in 1H NMR spectra declined from surface to deep marine SPE-DOM, whereas C-based aliphatics and carboxyl-rich alicyclic molecules (CRAM) increased in abundance. Surface SPE-DOM contained fewer methyl esters than all other samples, likely a consequence of direct exposure to sunlight. Integration of 13C NMR spectra revealed continual increase of carboxylic acids and ketones from surface to depth, reflecting a progressive oxygenation, with concomitant decline of carbohydrate-related substructures. Aliphatic branching increased with depth, whereas the fraction of oxygenated aliphatics declined for methine, methylene and methyl carbon. Lipids in the oldest SPE-DOM at 5446 m showed a larger share of ethyl groups and methylene carbon than observed in the other samples. Two-dimensional NMR spectra showed exceptional

  5. Measurement of Pulsed Power Supply

    2001-01-01

    Power supply system is an important subsystem of CSR. To apply for running, the parameters of power supply must be fit the design’s demands. We have tested all prototype of power supply as follows.The DC stability measurement is that the power supply runs in certain current level from the lower value to the normal value. In every current level, we acquire about 550 data by digital meter (model 7081) in 8 h.

  6. Nonlinear adaptive power-level control for modular high temperature gas-cooled reactors%模块式高温气冷堆的非线性自适应功率控制

    董哲

    2013-01-01

    Because of its inherent safety feature and potential economic competitiveness,the modular high temperature gas-cooled reactor (MHTGR) is regarded as the central part of the next generation of nuclear plant(NGNP).Power-level control is one of the key techniques that guarantee the safe,stable and efficient operation for any nuclear reactors.Since the MHTGR dynamics have the characteristics of strong nonlinearity and uncertainty,which can improve the operation performance.It is significant to develop the nonlinear adaptive power-level control er for the MHTGR.Based on the natural dynamic features beneficial to system stabilization,a novel nonlinear adaptive power-level controller is given for the MHTGR in this paper.It has proved theoretical y that this newly-built control er not only provides the overal asymptotic closed-loop stability,but also is adaptive to the system uncertainty.This control er has been applied in the power-level regulation of the pebble-bed MHTGR of the HTR-PM power plant.Numerical simulation results confirm the feasibility of this control strategy and the relationship between the performance and parameters.%由于具有固有安全性和潜在经济竞争力,模块式高温气冷堆(Modular High Temperature Gas-cooled Reactor, MHTGR)已被视为下一代核能系统的首选堆型之一。功率调节是保证MHTGR安全、稳定和高效运行的关键技术之一,而MHTGR在动态特性上具有非线性强和不确定性大的特点,因此发展MHTGR的非线性自适应功率控制器对于提升运行性能具有重要意义。在充分利用系统自身对镇定有益的动态特性的基础上,本文给出一种新颖的MHTGR非线性自适应功率控制器,并从理论上证明该控制器既可以保证闭环系统的全局渐近稳定性,又对系统不确定性具有自适应功能。数值仿真结果不仅验证了控制器的可行性,而且还给出了调节性能与控制器参数间的关系。

  7. High-field NMR spectroscopy and FTICR mass spectrometry: powerful discovery tools for the molecular level characterization of marine dissolved organic matter

    N. Hertkorn

    2013-03-01

    Full Text Available High-performance, non-target, high-resolution organic structural spectroscopy was applied to solid phase extracted marine dissolved organic matter (SPE-DOM isolated from four different depths in the open South Atlantic Ocean off the Angola coast (3° E, 18° S; Angola Basin and provided molecular level information with extraordinary coverage and resolution. Sampling was performed at depths of 5 m (Angola Current; near-surface photic zone, 48 m (Angola Current; fluorescence maximum, 200 m (still above Antarctic Intermediate Water, AAIW; upper mesopelagic zone and 5446 m (North Atlantic Deep Water, NADW; abyssopelagic, ~30 m above seafloor and produced SPE-DOM with near 40% carbon yield and beneficial nuclear magnetic resonance (NMR relaxation properties, a crucial prerequisite for the acquisition of NMR spectra with excellent resolution. 1H and 13C NMR spectra of all four marine SPE-DOM showed smooth bulk envelopes, reflecting intrinsic averaging from massive signal overlap, with a few percent of visibly resolved signatures and variable abundances for all major chemical environments. The abundance of singly oxygenated aliphatics and acetate derivatives in 1H NMR spectra declined from surface to deep marine SPE-DOM, whereas C-based aliphatics and carboxyl-rich alicyclic molecules (CRAM increased in abundance. Surface SPE-DOM contained fewer methyl esters than all other samples, likely a consequence of direct exposure to sunlight. Integration of 13C NMR spectra revealed continual increase of carboxylic acids and ketones from surface to depth, reflecting a progressive oxygenation, with concomitant decline of carbohydrate-related substructures. Aliphatic branching increased with depth, whereas the fraction of oxygenated aliphatics declined for methine, methylene and methyl carbon. Lipids in the oldest SPE-DOM at 5446 m showed a larger share of ethyl groups and methylene carbon than observed in the other samples. Two-dimensional NMR spectra showed

  8. 基于高层 LISA功耗模型的 RISC处理器热量分析与仿真方法%Thermal Analysis and Simulation for RISC Processor Based on High-level LISA Power Model

    岳丹; 徐抒岩; 聂海涛; 王刚

    2015-01-01

    为了优化集成电路芯片的布局封装,提高芯片性能及可靠性,对处理器级别的实时片上温度调节技术进行评估,给出了一种实时计算芯片单元模块功耗和温度的仿真方法。采用高层LISA功耗模型,得到 RISC处理器上通用应用程序的实时功耗;利用芯片后端设计软件Cadence Encounter对芯片进行布局规划设计,获得RISC处理器的floorplan信息;将实时功耗、floorplan信息及芯片规格参数作为输入信息,利用 HotSpot热量分析工具,实现对RISC处理器快速低代价的热量分析仿真。实验结果表明,利用该方法可以准确分析芯片的热分布,获得反映芯片在实际运行过程中热量分布的数据,为优化集成电路芯片的布局封装、分析芯片性能及可靠性等提供最直接的温度信息。%In order to optimize layout and packaging of IC chip ,improve its performance and reliability and evaluate runtime regulation technology of operating temperature on processor‐level , a real‐time simulation method of calculating unit‐based power consumption and runtime temperature is presented .By using high‐level LISA power model ,a runtime power consumption of generic applications on RISC processor is gained .Floorplan information about the RISC processor is obtained by Cadence Encounter software .HotSpot thermal analysis tool conducts fast , low‐cost thermal analysis for RISC processor using the real‐time power consumption ,floorplan information and RISC chip′s specifications as input information .The experiment results show that the method can accurately analyze heat distribution of the RISC chips and obtains the temperature data which can reflect the heat distribution during actual operation .It provides the most direct temperature information for optimizing layout and packaging of IC chip , analyzing its performance and reliability ,etc .

  9. 大数据分析方法在厂级负荷分配中的应用%Application of Big Data Analytics in Plant-level Load Dispatching of Power Plant

    王宁玲; 付鹏; 陈德刚; 杨志平; 杨勇平

    2015-01-01

    传统厂级负荷优化分配以火电机组煤耗曲线为依据,以供电煤耗率最低为目标。考虑到火电机组结构日益复杂,多变的边界条件和运行工况加剧了机组能耗特性的不确定性,给厂级负荷优化分配带来新问题。该文基于火电机组的海量运行数据,引入大数据分析方法,通过模糊粗糙集计算方法提高数据处理的效率,利用决策相关函数评价能耗决策的置信度,获得机组不同边界和运行工况下的能耗特性。将得到的机组供电煤耗率作为厂级负荷动态规划的依据,进而预测负荷优化分配的节煤潜力。结果表明,基于大数据分析方法的厂级负荷分配可有效降低火电厂的供电煤耗率,对火电机组的节能发电调度具有参考意义。%On the basis of coal rate curves, the traditional plant-level load dispatching is fulfilled with the minimum coal rate. Considering the increasing complexity in power unit structure, it is of great uncertainties to describe the energy consumption and difficult for the plant-level load dispatching especially under the varying operation boundary and conditions. With a great volume of operation data of thermal power units, big data-based analytics were introduced. The fuzzy rough set (FRS) method was used to improve the efficiency of data processing, and the decision correlation function was introduced to measure the confidence, so as to derive the coal rate under specific working conditions. Taking such coal rate as the basis of plant-level dynamic load planning, the energy-saving potential was predicted for the optimized load dispatching. The result shows that the load dispatching based on big data analytics is effective to reduce the gross coal rate, making great reference for the energy-saving power generation dispatching.

  10. Study on warpage of a strip level power module in packaging assembly process%封装集成工艺中带状功率器件的翘曲研究

    顾江海; 刘勇; 梁利华

    2012-01-01

    基于子结构法对封装集成工艺中带状功率器件的翘曲问题进行了研究,讨论了子结构法和非子结构法的优劣.采用实验性设计(Design of experiment,DoE),分别研究了嵌入式系统封装中低边芯片和高边芯片厚度、环氧模塑封(Epoxy mold compound,EMC)材料厚度、以及玻璃纤维(Prepreg)材料Z向弹性模量和EMC弹性模量对带状翘曲的影响.结果表明:子结构方法能够高效、简便和准确地模拟带状功率器件的翘曲问题;芯片、EMC厚度的变化对封装工艺中带状功率器件翘曲变形影响较大,Prepreg的Z向弹性模量和EMC的弹性模量E的变化对封装工艺中带状功率器件翘曲变形影响较小.%The warpage of a strip level power module in packaging assembly process is studied based on the substructure method. The comparison between substructure and non-substructure methods is made and discussed. By using design of experiment (DOE) method, the impact of low side (LS) and high side (HS) die thickness, epoxy mold compound (EMC) thickness, as well as the Young's modulus of prepreg and Young's modulus of EMC on the strip level warpage is conducted. It is found that substructure method is able to capture strip level power module warpage characteristics with high efficiency. The simulation results of substructure method agree reasonably well with non-substructure method. The numerical results show that die thickness and EMC thickness have an obvious impact on the warpage of a strip power modules, while the Young's modulus of prepreg and Young's modulus of EMC has less impact on it.

  11. Powering FITL for Deutsche Telekom

    Schulz, W. [T-Nova Deutsche Telekom Innovationsgesellschaft mbH Technologiezentrum (Germany)

    2000-07-01

    Deutsche Telekom introduced the project OPAL (optical access line) 8 years ago. The development of new applications for FITL (FTTH, FTTB, FTTC) leads to new challenges for power systems. For the establishment of an optical fibre infrastructure at the subscriber line level a wide variety of possible optical fibre network topologies can be imagined. Different powering architectures must be developed including remote or local powering. This paper presents results and performances of the powering configurations to feed the optical network units (ONU) and remote OLT. Compared to conventional powering the centralised powering with remote feeding supply was implemented to power the ONU in the field economically. (orig.)

  12. 分布式光伏电站过程层设备通讯故障的探讨%Discussion on the Communication Malfunction of the Process Level Equipment in Distributed PV Power Station

    葛琪; 苏战辉; 谢红伟; 董永超; 霍富强

    2016-01-01

    The automatic control system of distributed grid connected photovoltaic (PV)power sta-tion plays a critical role in the safe production.In this paper,the author analyzed the communication mal-function of the process level equipment,and based on the operation mechanism and features of the electri-cal equipment in PV power station as well as the on site troubleshooting experiences,concluded that the reason of such malfunction was the optical fiber netstorm,grounding grid failure,and inverter common mode interference.In addition,some corresponding solutions were proposed,providing references for pro-cessing the failure in the domestic large scale distributed grid connected PV power station,which will promote the healthy development of the PV industry.%分布式并网光伏电站自动化监控系统在电站的安全生产中占有关键地位,针对过程层设备通讯故障的研究分析,根据光伏电站电气设备的运行机理及特性,并结合一定的现场故障处理经验,将过程层通信故障原因归纳为光纤环网风暴、接地网故障和逆变器共模干扰,并提出工程中相应的处理方法,为国内大型分布式并网光伏电站故障处理提供一定的参考依据,推动光伏产业的健康发展。

  13. Study on year-end water level of multi-year regulating storage reservoir in power market%电力市场环境下多年调节水库年末消落水位研究

    原文林; 王福岭

    2012-01-01

    针对梯级水库中多年调节水库年末消落水位优选问题,结合电力市场环境下梯级水库中长期发电优化调度的特点,本文建立了电力市场环境下多年调节水库年末消落水位优选模型,并应用协同差分演化算法对模型进行了求解。通过乌江梯级水库实例验证,计算结果表明本文所提出的模型与求解方法具有可靠性与合理性,为电力市场环境下梯级水库发电优化调度提供了理论计算依据,具有应用推广价值。%In this paper, an optimal model is developed to simulate the year-end water level of a multi-year regulating storage reservoir in a cascade reservoirs system. This model considers power market environments and long-term scheduling of power generation, and is solved with a co-evolution differential evolution algorithm. Its effectiveness and reliability are verified through an application to the Wujiang cascade reservoirs. This study provides a theoretical basis for calculation of optimal scheduling of the cascade reservoirs in power market environments.

  14. 火电厂燃煤和粉煤灰及炉渣中天然放射性水平分析%The Natural Radioactive Level of the Coal,Coal Cinder and Slag from Power Plants

    谢贵英; 涂传火; 李艾尔肯·阿不列木

    2011-01-01

    The γ-ray spectrometer was used to analyze the natural radioactive level of the coal, coal cinder and slag from China power plant and state power plant in Urumqi. The average value of 226Ra 、232Th、and40K of coal is 5.54 、 3.51、 69.15Bq/Kg , the coal cinder is 26.99 、 15.89、 122.69Bq/Kg , the slag from China power plant is 28.79、15.98、 116.72Bq/Kg . The result reveals that the coal cinder's application range has no limit according to national standard.%本文采用低本底γ能谱仪对乌鲁木齐市华电和国电两个电厂的燃煤、粉煤灰和炉渣中的天然放射性核素含量进行了测量.测量结果:226Ra、232Th、40K含量的平均值,煤中分别为5.54、3.51、69.15Bq/Kg,粉煤灰中分别为26.99、15.89、122.69Bq/Kg,炉渣样中分别为28.79、15.98、116.72Bq/Kg.并依据国家标准对粉煤灰进行分类,结果表明,粉煤灰的使用不受限制.

  15. 基于联合编程的火电厂厂级AGC系统设计与实现%Design and Implementation of the Plant-level AGC System in Thermal Power Plants Based on Joint Programming

    童垚; 李戈阳

    2013-01-01

    Aimed at the realization of the plant-level automatic generation control(AGC) system in thermal power plants, a combined program approach based on C language and Composer configuration language is proposed. Solved the limitations of DCS configuration language in complex operation, realized the complex algorithm in plant-level AGC system under DCS, and developed the plant-level AGC system. The approach is simple and effective, can be widely used in the control systems which include complex algorithms.%针对火电厂厂级自动发电控制(Automatic Generation Control,AGC)系统的软件编程,文章提出了一种基于coldfire编译器的C语言与Composer组态语言联合编程方案,解决了分布式控制系统(distributed control systems,DCS)组态语言对复杂算法的局限性,在DCS上实现了厂级AGC的负荷优化分配和机组性能计算等复杂运算,并开发了DCS下的厂级AGC系统.该方法简洁有效,也可用于其它具有复杂运算的控制系统.

  16. Power marketing and renewable energy

    Fang, J.M.

    1997-09-01

    Power marketing refers to wholesale and retail transactions of electric power made by companies other than public power entities and the regulated utilities that own the generation and distribution lines. The growth in power marketing has been a major development in the electric power industry during the last few years, and power marketers are expected to realize even more market opportunities as electric industry deregulation proceeds from wholesale competition to retail competition. This Topical Issues Brief examines the nature of the power marketing business and its relationship with renewable power. The information presented is based on interviews conducted with nine power marketing companies, which accounted for almost 54% of total power sales by power marketers in 1995. These interviews provided information on various viewpoints of power marketers, their experience with renewables, and their respective outlooks for including renewables in their resource portfolios. Some basic differences exist between wholesale and retail competition that should be recognized when discussing power marketing and renewable power. At the wholesale level, the majority of power marketers stress the commodity nature of electricity. The primary criteria for developing resource portfolios are the same as those of their wholesale customers: the cost and reliability of power supplies. At the retail level, electricity may be viewed as a product that includes value-added characteristics or services determined by customer preferences.

  17. Development and Application of Mine-used Wind Power Automatic Liquid Level Control Drainage Switch%矿用风动力液位自控排水开关的研制与应用

    秦加增; 玄登程

    2014-01-01

    Mine submersible pump is widely used in the coal mine drainage, but over setting of submersible pump has caused huge waste of mine power supply, equipment using and the energy consumption. In order to achieve the multi-win goal of mine drainage, safety in production and energy conservation, the submersible pump wind power automatic liquid level control drainage switch is designed, and its principle and structure are introduced.%矿井潜水泵广泛使用于煤矿井下排水,过多的布置使用给矿井供电、设备使用和能源消耗造成极大的浪费。为达到矿井排水与安全生产和能源节约的多项共赢,设计制作了潜水泵风动力液位自控排水开关,并介绍其原理和结构。

  18. Analysis of Information Security Risks Internal Control Management System of the City Level Power Grid Enterprise%浅析地市级电网企业信息安全风险内控管理体系建设

    蒋友志

    2012-01-01

    在市场经济体制促进下,电网企业的信息安全管理体制迎来了新发展。文中阐述了ISO/IEC27001标准下电网企业信息安全风险内控管理需要的内容与体系,并通过某地级市的电网企业为研究对象,构建出科学合理的信息安全管理体系,对使用中出现的问题提出了合理建议。%With the promotion of the market economy system, the power grid enterprise information security manage- ment system has new developed. This paper elaborates the need contents and system in the ISO/IEC 27001 standard, and taking a city level power grid enterprise as the research object, construct scientific and reasonable information security man- agement system, and puts forward reasonable suggestions for problems in using.

  19. Thermal Hydraulic Analysis of 3 MW TRIGA Research Reactor of Bangladesh Considering Different Cycles of Burnup

    M.H. Altaf

    2014-12-01

    Full Text Available Burnup dependent steady state thermal hydraulic analysis of TRIGA Mark-II research reactor has been carried out utilizing coupled point kinetics, neutronics and thermal hydraulics code EUREKA-2/RR. From the previous calculations of neutronics parameters including percentage burnup of individual fuel elements performed so far for 700 MWD burnt core of TRIGA reactor showed that the fuel rod predicted as hottest at the beginning of cycle (fresh core was found to remain as the hottest until 200 MWD of burn, but, with the progress of core burn, the hottest rod was found to be shifted and another rod in the core became the hottest. The present study intends to evaluate the thermal hydraulic parameters of these hottest fuel rods at different cycles of burnup, from beginning to 700 MWD core burnt considering reactor operates under steady state condition. Peak fuel centerline temperature, maximum cladding and coolant temperatures of the hottest channels were calculated. It revealed that maximum temperature reported for fuel clad and fuel centerline found to lie below their melting points which indicate that there is no chance of burnout on the fuel cladding surface and no blister in the fuel meat throughout the considered cycles of core burnt.

  20. Deadbeat Predictive Direct Power Control of Single-phase Three-level Pulse Rectifiers%单相三电平脉冲整流器无差拍预测直接功率控制

    马俊鹏; 宋文胜; 王顺亮; 冯晓云

    2015-01-01

    In order to improve the controller’s dynamic response and precision of single-phase three-level pulse rectifier applied in China railways high-speed 2 (CRH2) electric multiple units, a single-phase three-level pulse rectifier was firstly modeled with mathematical expression. Then the operating principle of direct power control (DPC) based on PI controller with the fixed switching frequency was analyzed. On this basis, a single-phase deadbeat DPC with autoregressive power prediction method was proposed. Compared with the traditional PI DPC method, the proposed DPC method can not only reduce the complexity of hardware design and software programming without the main voltage’s phase detector, such as phase-locked loop (PLL), but also improve dynamic response of the rectifier with load change with active and reactive power autoregressive prediction. Furthermore, a single-phase three-level space vector pulse width modulation (SVPWM) embedded neutral point voltage balance was combined with the proposed deadbeat predictive DPC method as the control system of single-phase three-level pulse rectifier. Finally, The deadbeat predictive DPC and the traditional DPC with PI controller were compared and verified in computer simulation and hardware-in-loop experimental test. A comparison of simulation and experimental results verifies the feasibility and effectiveness of the adopted deadbeat predictive DPC method.%以我国CRH2(China railways highspeed 2)型高速动车组的单相三电平脉冲整流器为研究对象,以提高其动态响应速度及控制精度为目的,该文首先建立单相三电平脉冲整流器数学模型,分析传统基于比例积分(proportional-integral, PI)控制器的定频直接功率控制(direct power control,DPC)的工作原理,在此基础上,提出一种基于自回归算法的单相无差拍功率预测DPC算法。与传统PI定频DPC算法相比,该DPC算法无需网压相位检测装置,如锁相环(phase locked

  1. Electric Power

    2008-01-01

    @@ China Council for the Promotion of International Trade Electric Power Industry Office (CCPIT Electric Power), one of the pro-fessional industrial branches of China Council for the Promotion of International Trade (CCPIT), was established in 2006.

  2. Power Electronics

    Iov, Florin; Ciobotaru, Mihai; Blaabjerg, Frede

    2008-01-01

    is to change the electrical power production sources from the conventional, fossil (and short term) based energy sources to renewable energy resources. The other is to use high efficient power electronics in power generation, power transmission/distribution and end-user application. This paper discuss the most...... emerging renewable energy sources, wind energy, which by means of power electronics are changing from being a minor energy source to be acting as an important power source in the energy system. Power electronics is the enabling technology and the presentation will cover the development in wind turbine...... technology from kW to MW, discuss which power electronic solutions are most feasible and used today....

  3. Normative Power

    The social sciences have many different understandings of ‘normative power', but in European Union (EU) studies normative power has three particular meanings. The first meaning of normative power is its emphasis on normative theory, that is, how we judge and justify truth claims in social science....... The second meaning of normative power is as a form of power that is ideational rather than material or physical. The third meaning of normative power is as a characterisation of an ideal type of international actor. Empirical studies of normative forms of power have analysed both the causal and constitutive...... effects of EU relations with the world in areas ranging from inter-regional relations, through traditional diplomacy, to environmental politics. Research areas of particular interest include the study of the interplay between physical, material and normative forms of power, as well as the constitutive...

  4. Power Talk

    Angjelichinoski, Marko; Stefanovic, Cedomir; Popovski, Petar

    2016-01-01

    A standard way to realize communication in microgrid control is to use an external communication network, such as modems for wireless or power-line communication, whose implementation may be inefficient in terms of deployment cost, complexity, and system stability. In this chapter we present...... a communication solution, denoted as power talk, which is solely based on the use of the existing microgrid power equipment (i.e., power electronics and buses). The pivotal idea is to modulate information in the power-related parameters of the microgrid buses by use of the flexibility of power electronic...... interfaces. The focus of the chapter is on the design of power talk solutions for DC microgrids with droop control. Specifically, the chapter presents the power talk implementation through modification of the droop parameters of the primary control loop, and investigates the design of modulation schemes...

  5. Control of a deareador level of a thermoelectric power station using modern control techniques; Control de nivel de un deareador de una central termoelectrica utilizando tecnicas de control moderno

    Chavez Estrada, Jose Israel

    1997-01-01

    The present work shows the implementation of the scheme of predictive control IMC (Internal Model Control) in order to control the level of the deareador of a combined cycle thermoelectric power station of (C.C.T.S.). The implementation has the purpose of looking for alternative strategies of control to the classic ones (PID`s) that more efficiently control the variables of interest, in addition to getting into the new control techniques of control. Following the philosophy of predictive control IMC the form to applying this technique is shown, as well as the implementation of this type of controllers. A comparison of predictive control IMC is made with the scheme of conventional control (three control elements PID`s ) used at present to control the level of the deareador in the Combined Cycle Thermoelectric Power stations of Dos Bocas, Veracruz, Mexico and of Gomez Palacio, Durango, Mexico. [Espanol] El presente trabajo muestra la implementacion del esquema de control predictivo IMC (Control con Modelo Interno) con el objeto de controlar el nivel del deareador de una Central Termoelectrica de Ciclo Combinado (C.T.C.C.). La implementacion tiene la finalidad de buscar estrategias de control alternas a las clasicas (PID`s) que controlen mas eficientemente la variable de interes, ademas de incursionar en las nuevas tecnicas de control. Siguiendo la filosofia del control predictivo IMC se muestra la forma de aplicar esta tecnica, asi como la implementacion de este tipo de controladores. Se hace una comparacion del control predictivo IMC con el esquema de control convencional (control de tres elementos PID`s) utilizando actualmente para controlar el nivel del deareador en las centrales termoelectricas de ciclo combinado de Dos Bocas, Veracruz y de Gomez Palacio, Durango en Mexico.

  6. Low power DCVSL circuits employing AC power supply

    2002-01-01

    In view of changing the type of energy conversion in CMOS circuits, this paper investigates low power CMOS circuit design, which adopts a gradually changing power clock. First, we discuss the algebraic expressions and the corresponding properties of clocked power signals. Then the design procedure is summed up for converting complementary CMOS logic gates employing DC power to the power-clocked CMOS gates employing AC power. On this basis, the design of differential cascode voltage switch logic (DCVSL) circuits employing AC power clocks is proposed. The PSPICE simulations using a sinusoidal power-clock demonstrate that the designed power-clocked DCVSL circuit has a correct logic function and low power characteristics. Finally, an interface circuit to convert clocked signals into the standard logic levels of a CMOS circuit is proposed, and its validity is verified by computer simulations.

  7. Influence of the power level of an ultra-sonic system on dental cavity preparation Influência do nível de potência de um sistema de ultra-som em preparos cavitários

    Érika Botelho Josgrilberg

    2007-12-01

    Full Text Available The aim of this study was to evaluate the shape of dental cavities made with the CVDentus® system using different ultrasound power levels. One standard cavity was made on the buccal aspect of 15 bovine incisors with a CVDentus® cylindrical bur (82142. The sample was divided into three groups: G1 - ultrasound with power II; G2 - ultrasound with power III; and G3 - ultrasound with power IV. A standardizing device was used to obtain standardized preparations and ultrasound was applied during one minute in each dental preparation. The cavities were sectioned in the middle, allowing observation of the cavity’s profile with a magnifying glass, and width and depth measurement using the Leica Qwin program. The Kruskal-Wallis (p O objetivo deste estudo foi avaliar o formato dos preparos cavitários realizados com o sistema CVDentus® utilizando potências variadas do ultra-som. Uma cavidade padronizada foi realizada na face vestibular de 15 incisivos bovinos utilizando as pontas cilíndricas CVDentus® (82142. A amostra foi dividida em 3 grupos: G1 - ultra-som com potência II; G2 - ultra-som com potência III; e G3 - ultra-som com potência IV. Foi utilizada uma máquina padronizadora de preparos cavitários e o ultra-som foi aplicado durante 1 minuto em cada preparo. As cavidades foram seccionadas no centro, permitindo a visualização do perfil cavitário em uma lupa estereoscópica, e esse foi medido em largura e profundidade por meio do programa Leica Qwin. O teste estatístico Kruskal-Wallis (p < 0,05 e o método de Dunn demonstraram diferenças entre os formatos das cavidades produzidas com as potências III e IV. Entretanto, as cavidades realizadas com a potência III apresentaram dimensões semelhantes às da ponta utilizada. Concluiu-se que a potência indicada pelo fabricante (III é a mais adequada para uso do sistema CVDentus®.

  8. Tritium-Powered Radiation Sensor Network

    2015-09-01

    electrical components need to be activated. The sensor- chain components are the comparator, digital potentiometer, a 30-V power supply , and a GPS sensor...unlimited. 13. SUPPLEMENTARY NOTES 14. ABSTRACT Isotope power supplies offer solutions for long-lived (100 years), low-power (100 μWe) energy sources...Energy harvesting levels of power are consistent with the power levels supplied by isotope power sources

  9. 西安灞桥燃煤电厂周围土壤天然放射性水平%Natural Radioactivity Level in Soil Around Baqiao Coal-fired Power Plant

    赵彩凤; 卢新卫; 杨光; 李楠; 任春辉

    2012-01-01

    Natural radioactivity in soil around Baqiao coal - fired power plant had been measured by using a Nal ( Tl) γ - ray spectrometry. The results show that the specific activity of 226Ra,232Th and 40K in soil samples ranges from 27.60 to 48.78, 44. 39 to 61. 39 and 640.19 to 992. 25 Bq/kg with an average of 36.07 , 51. 13 and 733.91 Bq/kg, respectively. The average activity of 226Ra in soil around the power plant is greater than the average of Shaanxi soil, while slightly less than the average of Chinese soil. The average activity of Th and K in the studied soil samples are higher than the average level of Shaanxi soil and Chinese soil. The concentrations of 226Ra and 232Th in soil samples collected within 1000 m sites to coal - fired power plant boundary show no significantly spatial differences, whereas K concentration in soil samples collected from 100 m sites is less than from 400 m and 1 000 m sampling sites. The evaluation results of radium equivalent activity, air absorbed dose rate and annual effective dose rate show that coal - fired power plant affected the natural radioactivity level of surrounding soil, but natural radioactivity of soil is in normal level.%应用低本底多道γ能谱仪测定了燃煤电厂周围土壤中天然放射性核素226 Ra、232Th和40K的比活度,评价了其辐射危害.测定结果表明,土壤中226 Ra、232Th和40K的比活度分别为27.60~ 48.78、44.39~ 61.39和640.19~ 992.25 Bq/kg,平均值分别为36.07、51.13和733.91 Bq/kg.电厂周围土壤中226Ra比活度大于陕西土壤平均水平,稍小于全国土壤平均值;232 Th和40K比活度均大于陕西省土壤和全国土壤平均水平.在距离电厂1 000 m范围内,土壤中226Ra和232Th无明显空间差异,而40K比活度在距电厂100 m处土壤中明显低于400 m和1000m处.等效镭活度、空气吸收剂量率和年有效剂量率评价结果表明,燃煤发电对灞桥电厂周围土壤放射性有一定影响,但放射性水平处于正常.

  10. Plasma engineering studies for Tennessee Tokamak (TENTOK) fusion power reactor

    Yokoyama, K.E.; Lacatski, J.T.; Miller, J.B.; Bryan, W.E.; King, P.W.; Santoro, R.T.; Uckan, N.A.; Shannon, T.E.

    1984-02-01

    This paper summarizes the results of the plasma engineering and systems analysis studies for the Tennessee Tokamak (TENTOK) fusion power reactor. TENTOK is a 3000-MW(t) central station power plant that uses deuterium-tritium fuel in a D-shaped tokamak plasma configuration with a double-null poloidal divertor. The major parameters are R/sub 0/ = 6.4 m, a = 1.6 m, sigma (elongation) = 1.65, (n) = 1.5 x 10/sup 20/ m/sup -3/, (T) = 15 keV, (..beta..) = 6%, B/sub T/ (on-axis) = 5.6 T, I/sub p/ = 8.5 MA, and wall loading = 3 MW/m/sup 2/. Detailed analyses are performed in the areas of (1) transport simulation using the one-and-one-half-dimensional (1-1/2-D) WHIST transport code, (2) equilibrium/poloidal field coil systems, (3) neutral beam and radiofrequency (rf) heating, and (4) pellet fueling. In addition, impurity control systems, diagnostics and controls, and possible microwave plasma preheating and steady-state current drive options are also considered. Some of the major features of TENTOK include rf heating in the ion cyclotron range of frequencies, superconducting equilibrium field coils outside the superconducting toroidal field coils, a double-null poloidal divertor for impurity control and alpha ash removal, and rf-assisted plasma preheating and current startup.

  11. Flower power; Flower-Power

    Wiedemann, Karsten

    2010-08-15

    Scientists of Kassel university developed a concept for producing heat and electric power from grassland biomass. This strategy of decentral heat and power supply will also contribute to conservation goals. (orig.)

  12. Stockholm Power Tech. Power systems

    NONE

    1995-11-01

    The proceedings from this symposium is presented in six volumes: Invited speakers` sessions; Power systems; Power electronics; High-voltage technology; Electrical machines and drives; and Information and control systems. This report covers the power systems volume. Separate abstracts have been prepared for 141 of the 145 papers in this volume

  13. Noise Exposure Level in Workers of a Pumped Storage Power Station%某抽水蓄能电站运行人员噪声暴露水平检测与分析

    刘跟生

    2013-01-01

    [ Objective ] To evaluate noise exposure levels of workers in pumped storage power stations. [ Methods ] Individual noise exposure levels in 2 patrolling workplaces and 1 control room and in both operating and alternative conditions were measured. A mathematical calculation based on individual exposure level and exposure time was used to evaluate workers' noise exposure of 42 h per week which was then converted to the time equivalent continuous A-weighted sound pressure level (Laeq) of 40 h per week. [ Results ] In this study, the noise exposure levels in 2 patrolling workplaces and 1 control room were measured 3 times a day in both operating and alternative conditions. The workers' Laeq of 42 h per week was 62.1 dB (A) . After conversion, the workers' Laeq of 40h per week was 62.3 dB (A). [ Conclusion ] The noise exposure levels of workers in pumped storage power station do not exceed the occupational exposure limit of 85dB (A) prescribed in Occupational exposure limits for hazardous agents in the workplace Part 2: Physical agents.%[目的]分析抽水蓄能电站运行人员的噪声暴露水平. [方法]检测运行人员在运行工况及备用工况每次巡检时的接噪强度以及巡检后控制室的噪声强度,结合运行人员在不同情况下的接噪时间,计算运行人员在四值三运转的工作制度下,1周42h接触噪声强度的等效声级,进而换算至1周40h接触噪声强度的等效声级. [结果]本研究共检测6次运行工况及3次备用工况下的个体噪声及控制室噪声,经过计算分析,得出运行人员1周42h接触噪声的等效连续A声级为62.1 dB(A),换算至1周40h接触噪声的等效连续A声级为62.3 dB(A). [结论]抽水蓄能电站运行人员的噪声暴露水平未超过《工作场所有害因素职业接触限值第2部分:物理因素》(GBZ 2.2-2007)中规定的职业接触限值85dB(A).

  14. Wind turbine sound power measurements.

    Keith, Stephen E; Feder, Katya; Voicescu, Sonia A; Soukhovtsev, Victor; Denning, Allison; Tsang, Jason; Broner, Norm; Richarz, Werner; van den Berg, Frits

    2016-03-01

    This paper provides experimental validation of the sound power level data obtained from manufacturers for the ten wind turbine models examined in Health Canada's Community Noise and Health Study (CNHS). Within measurement uncertainty, the wind turbine sound power levels measured using IEC 61400-11 [(2002). (International Electrotechnical Commission, Geneva)] were consistent with the sound power level data provided by manufacturers. Based on measurements, the sound power level data were also extended to 16 Hz for calculation of C-weighted levels. The C-weighted levels were 11.5 dB higher than the A-weighted levels (standard deviation 1.7 dB). The simple relationship between A- and C- weighted levels suggests that there is unlikely to be any statistically significant difference between analysis based on either C- or A-weighted data.

  15. Thermionic power system power processing and control

    Metcalf, Kenneth J.

    1992-01-01

    Thermionic power systems are being considered for space-based miltary applications because of their survivability and high efficiency. Under the direction of the Air Force, conceptual designs were generated for two thermionic power systems to determine preliminary system performance data and direct future component development. This paper discusses the power processing and control (PP&C) subsystem that conditions the thermionic converter power and controls the operation of the reactor and thermionic converter subsystems. The baseline PP&C design and design options are discussed, mass and performance data are provided, and technology needs are identified. The impact on PP&C subsystem mass and efficiency of alternate power levels and boom lengths is also presented. The baseline PP&C subsystem is lightweight and reliable, and it uses proven design concepts to minimize development and testing time. However, the radiation dosages specified in the program research and development announcement (PRDA) are 10 to 100 times the capabilities of present semiconductor devices. While these levels are aggressive, they are considered to be achievable by 1995 if the Air Force and other government agencies continue to actively develop radiation resistant electronics devices for military applications.

  16. 高精度超声波液位测量系统的设计与实现%Design and Implementation of Low Power Consumption Ultrasonic Liquid Level Testing System

    卢伟; 王杨; 赵红东; 渠建兵; 夏克文

    2013-01-01

    To solve the problem of higher power consumption and lower accuracy in the existing measuring system,ultrasonic liquid level measuring system based on MSP430F149 was introduced.The system realized the design of hardware circuit and software algorithm,and it has the advantage of low power consumption and high measure accuracy.This paper focused on the system configuration,the design method to improve the accuracy and the experimental results.Experimental results show that the measured data is accurate between 20 cm and 1 500 cm and precision can reach 2 mm in the empty laboratory with the temperature of 25 ℃.Compared with other designs,this system has higher accuracy,reliability,practicability,so it can be better used in the industrial field.%文中针对现有的液位测量系统功耗较大、精度有待提高等问题,设计了一种基于MSP430F149单片机的高精度低功耗超声波液位测量系统.该系统实现了硬件电路的设计和软件算法的开发.文中重点分析了系统组成、提高精确度的设计方法和实验结果.实验表明:在环境温度为25℃的空旷实验室内,该系统测量范围为20~1 500 cm,测量精确度可达2 mm.相比于其他设计,该系统有更高的精确度,并且有较高的可靠性和实用性,可以更好地满足各种工业现场的需求.

  17. Space Nuclear Power Systems

    Houts, Michael G.

    2012-01-01

    Fission power and propulsion systems can enable exciting space exploration missions. These include bases on the moon and Mars; and the exploration, development, and utilization of the solar system. In the near-term, fission surface power systems could provide abundant, constant, cost-effective power anywhere on the surface of the Moon or Mars, independent of available sunlight. Affordable access to Mars, the asteroid belt, or other destinations could be provided by nuclear thermal rockets. In the further term, high performance fission power supplies could enable both extremely high power levels on planetary surfaces and fission electric propulsion vehicles for rapid, efficient cargo and crew transfer. Advanced fission propulsion systems could eventually allow routine access to the entire solar system. Fission systems could also enable the utilization of resources within the solar system.

  18. Modernization of the feedwater heaters control level of the Almaraz I Nuclear Power Plant by OVATION system; Modernizacion del control de nivel de los calentadores de agua de alimentacion de C.N. Almaraz I mediante el sistema OVATION

    Madronal Rodriguez, E.; Cabrero Munoz, J. E.

    2010-07-01

    As a result of the process of technological renovation of the heaters system and the power increase project, Almaraz Nuclear Power Plant has made several design changes in the feedwater heaters system. Within these changes, the old heaters control loops are replaced because the new power will increase the heaters drainage caudal. This modernization is carried out using the OVATION control system.

  19. Dissolution Power and Redistribution

    Becher, Michael

    2015-01-01

    While democracies vary in whether they allow their chief executives to dissolve parliament and call an early election, recent theories of the economic consequences of executive-legislative institutions in comparative politics pay little attention to dissolution power. I develop a model to analyze how chief executives' ability to dissolve the legislature influences the stability and level of redistribution. It shows that dissolution power critically alters the ability of partisan chief executi...

  20. Village power in Thailand

    Bergey, M.

    1997-12-01

    This paper presents an overview of the electric power system in Thailand. 99% of the country is electrified, but much of this is with diesel generators which leaves high costs but a high level of service. The paper discusses renewable energy projects which have been sited in the country, and examples of hybrid systems which have been retrofit into existing diesel generator systems. Photovoltaic and hydroelectric power projects are described. Dedicated systems have been installed for water pumping and battery charging applications.

  1. Techno-economic analysis of using corn stover to supply heat and power to a corn ethanol plant - Part 2: Cost of heat and power generation systems

    Mani, Sudhagar [University of Georgia; Sokhansanj, Shahabaddine [ORNL; Togore, Sam [U.S. Department of Energy; Turhollow Jr, Anthony F [ORNL

    2010-03-01

    This paper presents a techno-economic analysis of corn stover fired process heating (PH) and the combined heat and power (CHP) generation systems for a typical corn ethanol plant (ethanol production capacity of 170 dam3). Discounted cash flow method was used to estimate both the capital and operating costs of each system and compared with the existing natural gas fired heating system. Environmental impact assessment of using corn stover, coal and natural gas in the heat and/or power generation systems was also evaluated. Coal fired process heating (PH) system had the lowest annual operating cost due to the low fuel cost, but had the highest environmental and human toxicity impacts. The proposed combined heat and power (CHP) generation system required about 137 Gg of corn stover to generate 9.5 MW of electricity and 52.3 MW of process heat with an overall CHP efficiency of 83.3%. Stover fired CHP system would generate an annual savings of 3.6 M$ with an payback period of 6 y. Economics of the coal fired CHP system was very attractive compared to the stover fired CHP system due to lower fuel cost. But the greenhouse gas emissions per Mg of fuel for the coal fired CHP system was 32 times higher than that of stover fired CHP system. Corn stover fired heat and power generation system for a corn ethanol plant can improve the net energy balance and add environmental benefits to the corn to ethanol biorefinery.

  2. Techno-economic analysis of using corn stover to supply heat and power to a corn ethanol plant - Part 2: Cost of heat and power generation systems

    Mani, S. [Biological and Agricultural Engineering, Driftmier Engineering Center, University of Georgia, Athens, GA 30602 (United States); Sokhansanj, S.; Turhollow, A.F. [Environmental Sciences Division, Oak Ridge National Laboratory, P. O. Box 2008, Oak Ridge, TN 37831 (United States); Tagore, S. [Office of Biomass Program, U.S. Department of Energy, Washington, DC 20585 (United States)

    2010-03-15

    This paper presents a techno-economic analysis of corn stover fired process heating (PH) and the combined heat and power (CHP) generation systems for a typical corn ethanol plant (ethanol production capacity of 170 dam{sup 3}). Discounted cash flow method was used to estimate both the capital and operating costs of each system and compared with the existing natural gas fired heating system. Environmental impact assessment of using corn stover, coal and natural gas in the heat and/or power generation systems was also evaluated. Coal fired process heating (PH) system had the lowest annual operating cost due to the low fuel cost, but had the highest environmental and human toxicity impacts. The proposed combined heat and power (CHP) generation system required about 137 Gg of corn stover to generate 9.5 MW of electricity and 52.3 MW of process heat with an overall CHP efficiency of 83.3%. Stover fired CHP system would generate an annual savings of 3.6 M$ with an payback period of 6 y. Economics of the coal fired CHP system was very attractive compared to the stover fired CHP system due to lower fuel cost. But the greenhouse gas emissions per Mg of fuel for the coal fired CHP system was 32 times higher than that of stover fired CHP system. Corn stover fired heat and power generation system for a corn ethanol plant can improve the net energy balance and add environmental benefits to the corn to ethanol biorefinery. (author)

  3. When power shapes interpersonal behavior: Low relationship power predicts men's aggressive responses to low situational power.

    Overall, Nickola C; Hammond, Matthew D; McNulty, James K; Finkel, Eli J

    2016-08-01

    When does power in intimate relationships shape important interpersonal behaviors, such as psychological aggression? Five studies tested whether possessing low relationship power was associated with aggressive responses, but (a) only within power-relevant relationship interactions when situational power was low, and (b) only by men because masculinity (but not femininity) involves the possession and demonstration of power. In Studies 1 and 2, men lower in relationship power exhibited greater aggressive communication during couples' observed conflict discussions, but only when they experienced low situational power because they were unable to influence their partner. In Study 3, men lower in relationship power reported greater daily aggressive responses toward their partner, but only on days when they experienced low situational power because they were either (a) unable to influence their partner or (b) dependent on their partner for support. In Study 4, men who possessed lower relationship power exhibited greater aggressive responses during couples' support-relevant discussions, but only when they had low situational power because they needed high levels of support. Study 5 provided evidence for the theoretical mechanism underlying men's aggressive responses to low relationship power. Men who possessed lower relationship power felt less manly on days they faced low situational power because their partner was unwilling to change to resolve relationship problems, which in turn predicted greater aggressive behavior toward their partner. These results demonstrate that fully understanding when and why power is associated with interpersonal behavior requires differentiating between relationship and situational power. (PsycINFO Database Record

  4. 双三电平永磁直驱风力发电系统控制策略研究%Dual Three-level Permanent Magnet Direct Drive Wind Power System Control Strategy

    王斌; 王峰; 刘毅; 张杰

    2011-01-01

    为满足变流器容量需求并获取较低的电流谐波指标,降低开关损耗,达到良好的并网要求,直驱式风力发电系统采用永磁同步发电机(PMSG)和双三电平变流器相结合的拓扑结构.基于PMSG d,q坐标系下的数学模型,机侧变换器运用简化的空间矢量脉宽调制技术并结合PMSG的最大转矩电流比控制策略,充分利用凸极效应,提高系统运行效率,网侧变换器采用电压电流双闭环控制策略.利用Matlab软件建立直驱式永磁同步风力发电系统的仿真模型,并对风速突变时系统的动态特性进行研究.仿真结果表明,所建立模型具有较好的动态特性并验证了控制系统的正确性及有效性.%To meet the requirement for the capacity, low current harmonic level and low switching loss, direct-drive wind power generation system employed the topology which combined the permanent magnet synchronous generator (PMSG) and dual three-level PWM full-size converter.Based on d,q axis mathematical model of PMSG,in order to take full advantages of saliency effects, improve efficiency, the generator side adopts simplified space vector pulse width modulation technology combined with maximum torque per ampere control scheme.The grid side employes the dual close-loop control strategy which are the inner current-loop and the outer voltage-loop. The model of direct-drive wind power generation system is realized with the engineering software, Matlab for the case of wind speed stepping change shows the excellent dynamic performance of the model, in the same time, verifies the correctness and feasibili ty of the control strategy.

  5. Reassessing Power

    CHARLES; K.EBINGER; JOHN; P.BANKS

    2011-01-01

    Fukushima accident increases global concern over nuclear safety The accident at the Fukushima Daiichi Nuclear Power Plant in Japan has had an immediate impact on resurgent interest in nuclear power worldwide.Numerous governments have announced plans to re-examine nuclear energy policy and review the safety of their reactors and the adequacy of their regulatory frameworks.

  6. Diastatic power

    diastatic power: Diastatic power, abbreviated DP, is the total activity of malt starch degrading enzymes that hydrolyze starch to fermentable sugars. The starch degrading enzymes contributing to this process are a-amylase, ß-amylase, limit dextrinase, and a-glucosidase. The driving force for DP a...

  7. Power Drain

    2008-01-01

    Rising coal prices mean dwindling profits for China’s power plants. In some cases,they have forced plants to close their doors If electricity prices were not raised together with fuel prices, the country’spower plants could not survive. This isthe common voice of China’s power plants now.

  8. U.S. Forward Operating Base Applications of Nuclear Power

    Griffith, George W. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-01-01

    This paper provides a high level overview of current nuclear power technology and the potential use of nuclear power at military bases. The size, power ranges, and applicability of nuclear power units for military base power are reviewed. Previous and current reactor projects are described to further define the potential for nuclear power for military power.

  9. Power system

    Hickam, Christopher Dale

    2008-03-18

    A power system includes a prime mover, a transmission, and a fluid coupler having a selectively engageable lockup clutch. The fluid coupler may be drivingly connected between the prime mover and the transmission. Additionally, the power system may include a motor/generator drivingly connected to at least one of the prime mover and the transmission. The power-system may also include power-system controls configured to execute a control method. The control method may include selecting one of a plurality of modes of operation of the power system. Additionally, the control method may include controlling the operating state of the lockup clutch dependent upon the mode of operation selected. The control method may also include controlling the operating state of the motor/generator dependent upon the mode of operation selected.

  10. Exposure level and characteristics of dioxins in children living near the waste incineration power plant%垃圾焚烧发电地区儿童二(噁)英暴露水平及特征研究

    陈志健; 王晓峰; 莫哲; 沈海涛; 楼晓明

    2013-01-01

    目的 分析垃圾焚烧发电厂周边儿童体内二(噁)英负荷水平、分布特征和人群二(噁)英外暴露水平.方法 设距垃圾焚烧发电厂1km S镇为污染点,200km外的L镇为对照点,采集S镇90名及L镇60名10 ~11岁儿童外周静脉血,另采集两地土壤、鲫鱼和鸡蛋各3份,检测样本中二(噁)英浓度及计算毒性当量(TEQ)并分析对比.结果 污染点儿童血中二(噁)英浓度与TEQ均显著高于对照组(P<0.05);鸡蛋和鲫鱼中二(噁)英浓度与TEQ、土壤中二(噁)英浓度均显著高于对照组(P<0.05).两地样本的二(噁)英单体分布类似,其中单体浓度最高的为八氯代二苯并二(噁)英(OCDD),TEQ贡献最高的为2,3,4,7,8-五氯代二苯并呋喃(2,3,4,7,8-PeCDF).结论 垃圾焚烧发电厂周边土壤中二(噁)英浓度增高,当地儿童二(噁)英外暴露和内负荷水平均显著增高.%Objective To study the internal and external dioxins exposure level of children living near the waste incineration power plant. Methods Peripheral blood of children(90 in S, 60 in L) , soils, crucians, chicken eggs were sampled in town S(lkm away from a big waste incineration power plant) , as well as in town L( 200km away from S) , which is the control. The contents, distribution characteristics and toxic equivalent (TEQ) of dioxins in samples were evaluated by ultra-trace detection methods. Results The concentrations and TEQs of dioxins in blood, soils, crucians and chicken eggs from town S were significantly higher than those in town L ( P < 0. 05 ). The dominant dioxin detected from the samples is OCDD, while the dominant TEQ contribution dioxin is 2,3, 4,7,8-PeCDF. Conclusion The emission of dioxins from the waste incineration power plant may increase the internal and external dioxins exposure level of children living nearby.

  11. Effect of Equal Daily Doses Achieved by Different Power Densities of Low-Level Laser Therapy at 635 nm on Open Skin Wound Healing in Normal and Diabetic Rats

    Róbert Kilík

    2014-01-01

    Full Text Available Background and Objective. Despite the fact that the molecular mechanism of low-level laser therapy (LLLT is not yet known, the exploitation of phototherapy in clinical medicine and surgery is of great interest. The present study investigates the effects of LLLT on open skin wound healing in normal and diabetic rats. Materials and Methods. Four round full-thickness skin wounds on dorsum were performed in male adult nondiabetic (n=24 and diabetic (n=24 Sprague–Dawley rats. AlGaInP (635 nm, wavelength; 5 J/cm2, daily dose was used to deliver power densities of 1, 5, and 15 mW/cm2 three times daily until euthanasia. Results. PMNL infiltration was lower in the irradiated groups (15 mW/cm2. The synthesis and organisation of collagen fibres were consecutively enhanced in the 5 mW/cm2 and 15 mW/cm2 groups compared to the others in nondiabetic rats. In the diabetic group the only significant difference was recorded in the ratio PMNL/Ma at 15 mW/cm2. A significant difference in the number of newly formed capillaries in the irradiated group (5, 15 mW/cm2 was recorded on day six after injury compared to the control group. Conclusion. LLLT confers a protective effect against excessive inflammatory tissue response; it stimulates neovascularization and the early formation of collagen fibres.

  12. A Multi-objective Bi-level Optimization Strategy for Network Reconfiguration of Power Systems%电力系统网络重构的多目标双层优化策略

    张璨; 林振智; 文福拴; 薛禹胜; 王函韵; 吴鸣鸣

    2014-01-01

    First,a modified method for evaluating the importance of each node is presented,and a multi-obj ective bi-level optimization model for the network reconfiguration is proposed.In the upper-level optimization model,the start-up sequence of generating units is determined by maximizing the restored generation capacity.While in the lower-level,the restoration path is optimized by maximizing the average importance of the candidate restoration path and minimizing the charging capacitance of the same path,and in the formulation the impacts of the restoration path on the restoration of generating units are taken into account.A continuous dynamic Pareto multi-step apoptosis optimization strategy (MSAOP) is next proposed to solve the multi-obj ective optimization problem of the network reconfiguration problem with multi-step restoration by simulating the physiological characteristics of the cell,and in this way the scale and difficult degree of the optimization problem to be solved can be reduced,and the possible curse of dimensionality avoided as well.This optimization strategy focuses on the stage-wise optimal solution in the restoration path of the generating units,while the global optimality is also taken into account.In addition,the set of network reconfiguration strategies obtained in the restoration procedure can be depicted in the form of a branch graph.Then,a fuzzy decision-making (FDM) method is employed to determine the final network reconfiguration strategy.Finally,the New England 10-unit 39-bus power system and Guangzhou power system are employed to demonstrate the feasibility and efficiency of the developed model and method.%提出一种节点重要度综合评价新方法,并在此基础上发展了网络重构多目标双层优化模型。在上层优化模型中,以最大化系统可用发电容量确定发电节点恢复顺序;在下层确定恢复路径的多目标优化模型中,以最大化恢复路径的平均重要度和最小化路径的充电

  13. 论县级政府政策执行力提升的伦理意蕴%Ethical Implication of Enhancement of Policy Executive Power of County-Level Government

    李长根; 杨笋

    2014-01-01

    深化行政管理体制改革,创新行政管理方式,必须提高政府的公信力和执行力。这就要求县级政府在政策执行中必须体现“诚实守信”、“以民为本”、“公平正义”、“德法共治”和“清正廉明”的伦理观。文章分析了影响县级政府政策执行力提升的原因,提出了相应的提升县级政府政策执行力的对策建议:建设良好的县级政府执行力文化,培养良好的县域领导科学与艺术;加强伦理教育,优化社会环境;完善对公务员伦理品格及执行绩效的考核监控和监督;加强行政道德制度化建设,构建制度伦理等。%It is a must for the government to improve the credibility and executive power so as to deepen the administrative system reform and make innovations in the administrative management mode , which de-mands that the policy execution of county-level government should embody the ethics of “honesty and credibili-ty”,“fairness and justice”, “moral and legal co-governance”, “being people-oriented” and “being honest and free from corruption”.The paper analyzes the reasons affecting the enhancement of policy execution of county-level government , and puts forward the following suggestions:establishing good executive environment for county-level government and cultivating the science and art of county region leadership ;strengthening ethi-cal education and optimizing social environment;perfecting the evaluation , monitoring and supervision of the ethical character and executive performance of public servants;and enhancing the institutionalization of admin-istrative morality and constructing institutional ethics .

  14. Power Talk

    Liu, Hongpeng; Yang, Yongheng; Loh, Poh Chiang

    2016-01-01

    In this paper, a novel communication strategy called Power Talk is introduced to realize the power line communication among the Voltage Source Converters (VSC) of DC MicroGrids (MGs). Each VSC transmits information by changing the control parameters, and receives information by observing the local...... output power. By using common coding schemes, which transform the DC MGs in some familiar communication channels, some important communication challenges can be addressed, such as random load variations and VSCs switching, as it do not need a separate communication channel. For this purpose, two multiple...

  15. Power outages, power externalities, and baby booms.

    Burlando, Alfredo

    2014-08-01

    Determining whether power outages have significant fertility effects is an important policy question in developing countries, where blackouts are common and modern forms of family planning are scarce. Using birth records from Zanzibar, this study shows that a month-long blackout in 2008 caused a significant increase in the number of births 8 to 10 months later. The increase was similar across villages that had electricity, regardless of the level of electrification; villages with no electricity connections saw no changes in birth numbers. The large fertility increase in communities with very low levels of electricity suggests that the outage affected the fertility of households not connected to the grid through some spillover effect. Whether the baby boom is likely to translate to a permanent increase in the population remains unclear, but this article highlights an important hidden consequence of power instability in developing countries. It also suggests that electricity imposes significant externality effects on rural populations that have little exposure to it.

  16. Power Preservation

    Galster, Kjeld

    Power Preservation (Abstract) In the 17th century, just as today, coalitions needed ‘lead nations’. This was assumed to be a power with great military and economic potentials, and Denmark endeavoured to act as such a leader in the Thirty Years War from 1626 to 28. The results were not encouraging...... in the military field and they were disastrous as far as fiscal matters were concerned. Sweden took over the leadership of the protestant side and she took over Denmark’s place amongst the great powers of the Baltic Region. From that time onwards, Danish influence and options on the international stage gradually...... declined. Thus, Denmark of the 17th century is not to be counted amongst the great powers, but since Christian V’s accession to the throne in 1670 Denmark-Norway has developed into one of Europe’s most highly militarised states. Apart from a permanently combat ready navy, the country maintains a standing...

  17. Introduction to electrical power and power electronics

    Patel, Mukund R

    2012-01-01

    Power Generation, Distribution, and Utilization AC Power Fundamentals Common Aspects of Power Equipments AC Generator AC and DC Motors Transformer Power Cable Power Distribution Fault Current Analysis System ProtectionEconomic Use of PowerElectrochemical BatteryPower Electronics and Motor Drives Power Electronics Devices DC-DC Converters AC-DC-AC Converters Variable-Frequency Drives Quality of Power Power Converter CoolingAppendixIndex

  18. Management and Control of Special Budget for City Level Power Supply Enterprises——Based on the Business Practice of State Grid Huaibei Power Supply Company%地市供电企业专项预算管控——基于国网淮北供电公司业务实践

    赵会芹

    2015-01-01

    国网公司推行全面预算管理,专项预算是对全面预算专业化、职责化细分. 通过专项预算的编制、执行、控制、考核与激励等一系列活动,能够促进企业内部的沟通、协作,有效整合各类资源. 文章通过对地市供电企业专项预算管控工作的实践总结,提炼出"三结合、三链条"的专项预算执行全过程管控,希望能为供电企业预算管理提供有益借鉴.%State Grid Corporation of China carries out the comprehensive budget management , and the special budget is the professionalization and responsibility subdivision to the comprehensive budget . Through a series of activities such as the compilation , execution , control , assessment and stimulation of special budget , the enterprise internal communication and collaboration can be promoted , and the various resources can be integrated effectively .Based on the practice summary of the special budget management for the city level power supply company , this paper extracts the ″three combinations and three chains″way for the whole process management and control of the special budget , hoping to provide a useful reference for the budget management of power supply enterprises .

  19. Electric power annual 1992

    1994-01-06

    The Electric Power Annual presents a summary of electric utility statistics at national, regional and State levels. The objective of the publication is to provide industry decisionmakers, government policymakers, analysts and the general public with historical data that may be used in understanding US electricity markets. The Electric Power Annual is prepared by the Survey Management Division; Office of Coal, Nuclear, Electric and Alternate Fuels; Energy Information Administration (EIA); US Department of Energy. ``The US Electric Power Industry at a Glance`` section presents a profile of the electric power industry ownership and performance, and a review of key statistics for the year. Subsequent sections present data on generating capability, including proposed capability additions; net generation; fossil-fuel statistics; retail sales; revenue; financial statistics; environmental statistics; electric power transactions; demand-side management; and nonutility power producers. In addition, the appendices provide supplemental data on major disturbances and unusual occurrences in US electricity power systems. Each section contains related text and tables and refers the reader to the appropriate publication that contains more detailed data on the subject matter. Monetary values in this publication are expressed in nominal terms.

  20. Technical Description Lillgrund Wind Power Plant. Lillgrund Pilot Project

    Jeppsson, Joakim; Larsen, Poul Erik; Larsson, Aake (Vattenfall Vindkraft AB, Stockholm (Sweden))

    2008-09-15

    Lillgrund offshore wind power plant comprises 48 wind turbines, each rated at 2.3 MW, bringing the total wind farm capacity to 110 MW. The Lillgrund offshore wind power plant is located in a shallow area of Oeresund, 7 km off the coast of Sweden and 7 km south from the Oeresund Bridge connecting Sweden and Denmark. An average wind speed of around 8,5 m/s at hub height, combined with a relatively low water depth of 4 to 8 meters makes it economically feasible to build here. Vattenfall Vindkraft AB is the owner and operator of Lillgrund offshore wind power plant. Lillgrund is a Swedish pilot project supported by the Swedish Energy Agency. The bidding process was completed during 2005 and the offshore power plant was constructed in the period 2006 to 2007. The wind farm was constructed on time and has now been successfully operational since December 2007. There is, however, always potential for improvement and the aim of this report has been to determine and highlight these areas. It is worth noting out that only the electrical system and the foundations are tailor made at offshore wind power plants. The wind turbines are more or less standard products with none or very limited possibilities for project specific design changes. Geotechnical investigations are expensive and it can be difficult to balance the risks as well as the benefits of this expense in the early phases of a large infrastructure project. As a whole, the geotechnical surveys at Lillgrund proved to be useful. They identified potential issues, such as the fact that extra excavation was required for two of the foundations. It also revealed the location of a small number of boulders that would have to be removed. Vattenfall requested a complete study of the electrical system for Lillgrund to be delivered with the bids. That request was not met. Instead Siemens Wind Power began a complete electrical system study after being awarded the Contract. The electrical system study was completed during the

  1. Converter structure-based power loss and static thermal modeling of the press-pack IGBT-based three-level ANPC and HB VSCs applied to Multi-MW wind turbines

    Senturk, Osman Selcuk; Munk-Nielsen, Stig; Teodorescu, Remus

    2010-01-01

    and the switch thermal performance which is determined by the converter load profile and the converter structure. In this study, the converter-structure based power loss and thermal models are developed for the medium voltage full-scale 3LANPC- VSC and 3L-HB-VSC utilizing press-pack IGBT-diode pairs....... For the experimental model verifications, a test setup with a single-phase full-scale 3L-ANPC-VSC is introduced. Using the power loss and thermal models, the switch junction temperatures are obtained on simulation for the wind turbine grid interface. The power density and reliability of the VSCs are discussed......The wind turbine converters demand high power density due to nacelle space limitation and high reliability due to high maintenance cost. Once the converter topology with the semiconductor switch technology is selected, the converter power density and reliability are dependent on the component count...

  2. The measurement of 129I for the cement and the paraffin solidified low and intermediate level wastes (LILWs), spent resin or evaporated bottom from the pressurized water reactor (PWR) nuclear power plants.

    Park, S D; Kim, J S; Han, S H; Ha, Y K; Song, K S; Jee, K Y

    2009-09-01

    In this paper a relatively simple and low cost analysis procedure to apply to a routine analysis of (129)I in low and intermediate level radioactive wastes (LILWs), cement and paraffin solidified evaporated bottom and spent resin, which are produced from nuclear power plants (NPPs), pressurized water reactors (PWR), is presented. The (129)I is separated from other nuclides in LILWs using an anion exchange adsorption and solvent extraction by controlling the oxidation and reduction state and is then precipitated as silver iodide for counting the beta activity with a low background gas proportional counter (GPC). The counting efficiency of GPC was varied from 4% to 8% and it was reversely proportional to the weight of AgI by a self absorption of the beta activity. Compared to a higher pH, the chemical recovery of iodide as AgI was lowered at pH 4. It was found that the chemical recovery of iodide for the cement powder showed a lower trend by increasing the cement powder weight, but it was not affected for the paraffin sample. In this experiment, the overall chemical recovery yield of the cement and paraffin solidified LILW samples and the average weight of them were 67+/-3% and 5.43+/-0.53 g, 70+/-7% and 10.40+/-1.60 g, respectively. And the minimum detectable activity (MDA) of (129)I for the cement and paraffin solidified LILW samples was calculated as 0.070 and 0.036 Bq/g, respectively. Among the analyzed cement solidified LILW samples, (129)I activity concentration of four samples was slightly higher than the MDA and their ranges were 0.076-0.114 Bq/g. Also of the analyzed paraffin solidified LILW samples, five samples contained a little higher (129)I activity concentration than the MDA and their ranges were 0.036-0.107 Bq/g.

  3. Post-accident response of near-surface {sup 129}I levels and {sup 129}I/{sup 127}I ratios in areas close to the Fukushima Dai-ichi Nuclear Power Plant, Japan

    Matsunaka, Tetsuya, E-mail: matsunaka@tac.tsukuba.ac.jp [Accelerator Mass Spectrometry Group, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577 (Japan); Sasa, Kimikazu; Sueki, Keisuke; Takahashi, Tsutomu; Matsumura, Masumi; Satou, Yukihiko [Accelerator Mass Spectrometry Group, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577 (Japan); Kitagawa, Jun-ichi [Radiation Science Center, High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); Kinoshita, Norikazu [Institute of Technology, Shimizu Corporation, 3-4-17 Etchujima, Koto-ku, Tokyo 135-8530 (Japan); Matsuzaki, Hiroyuki [The University Museum, The University of Tokyo, 2-11-16 Yayoi, Bunkyo-ku, Tokyo 113-0032 (Japan)

    2015-10-15

    The deposition density and extent of subsurface infiltration of {sup 129}I were investigated within the area highly contaminated by the March 2011 accident at the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) in Japan. Depth profiles of {sup 129}I activity and {sup 129}I/{sup 127}I ratios were measured in 5-cm-long soil cores that were collected 20–27 months after the accident from three sites (S-1, S-2, and S-3) within 10 km to the west and northwest of the FDNPP. These profiles were compared with the background levels of {sup 129}I from the same areas. The deposition densities of {sup 129}I were 2.17 Bq m{sup −2} at S-1, 0.80 Bq m{sup −2} at S-2, and 1.41 Bq m{sup −2} at S-3, which are, respectively, about 160, 60, and 100 times larger than the background level (12.8–14.8 mBq m{sup −2}). The average {sup 129}I/{sup 127}I ratios in each soil core after the accident (S-1: 2.1 × 10{sup −6}; S-2: 4.2 × 10{sup −7}; S-3: 2.3 × 10{sup −6}) were similar to the value typically found in contaminated surface soil within 80 km of the FDNPP. Therefore, accident-derived {sup 129}I deposited at S-1 (4.3 km west of the FDNPP) was 2.7 times larger than at S-2 (8.2 km west of the FDNPP), and 1.5 times larger than at S-3 (7.5 km northwest of the FDNPP). Depth profiles showed that the {sup 129}I activity and {sup 129}I/{sup 127}I ratios decayed exponentially with depth. ∼90% of accident-derived {sup 129}I deposited in the soil cores was concentrated in the upper 25.2–26.4 kg m{sup −2} of mass depth (2.1–3.1 cm depth). The relaxation mass depths (h{sub 0}) of {sup 129}I were 9.49–11.2 kg m{sup −2} at the three sampling sites, and these values are comparable to those of accident-derived {sup 131}I (10.4 kg m{sup −2}) at a site 40 km northwest of the FDNPP.

  4. Pre- and post-accident (129)I and (137)Cs levels, and (129)I/(137)Cs ratios in soil near the Fukushima Dai-ichi Nuclear Power Plant, Japan.

    Matsunaka, Tetsuya; Sasa, Kimikazu; Sueki, Keisuke; Takahashi, Tsutomu; Satou, Yukihiko; Matsumura, Masumi; Kinoshita, Norikazu; Kitagawa, Jun-ichi; Matsuzaki, Hiroyuki

    2016-01-01

    To evaluate the deposition density and extent of subsurface infiltration of (129)I and (137)Cs in the restricted area that was highly contaminated by the accident of Fukushima Dai-ichi Nuclear Power Plant, cumulative inventories of (129)I and (137)Cs, concentrations of (129)I and (137)Cs, and (129)I/(137)Cs ratio in 30-cm-long soil columns were compared with pre-accident levels from the same area. The cores were collected before and after the accident from locations of S-1 (4 km west of FDNPP) and S-2 (8 km west of FDNPP). Deposition densities of (129)I and (137)Cs in the soil following the accident were 0.90-2.33 Bq m(-2) and 0.80-4.04 MBq m(-2), respectively, which were 14-39 and 320-510 times larger than the pre-accident levels of (129)I (59.3-63.3 mBq m(-2)) and (137)Cs (2.51-7.88 kBq m(-2)), respectively. Approximately 90% of accident-derived (129)I and (137)Cs deposited in the 30-cm soil cores was concentrated in the surface layer from 0 to 44-95 kg m(-2) of mass depth (0-4.3-6.2 cm depth) and from 0 to 16-25 kg m(-2) of mass depth (0-1.0-3.1 cm depth), respectively. The relaxation mass depths (h0) of 10.8-11.2 kg m(-2) for (129)I estimated in the previous study were larger than those of 8.1-10.6 kg m(-2) for (137)Cs at both sites, owing to the larger infiltration depth of radioiodine mainly by the gravitational water penetration in the surface soil in our study sites. Approximately 7-9% of the accident-derived (129)I was present in the lower layer from 44 to 100 kg m(-2) (4.3-8.6 cm depth) at S-1, and from 95 to 160 kg m(-2) (6.2-10.2 cm depth) at S-2. Approximately 1% of (137)Cs seems to infiltrate deeper than (129)I in the lower layer at each site in contrast to the surface layer.

  5. High Power Factor Power Design

    Zhang Jing-yi

    2013-07-01

    Full Text Available The PFC circuit takes UCC28019 made by TI Company as the core of system control, realize the power factor correction circuit functions, and the circuit power factor can be measured. Through a variety of detection circuit, with the support SCM control. And 30V~36V output voltage regulator can be set; with over-current protection circuits function, and be able to automatically back. Output current, voltage, and little significant value are displayed by display modules.

  6. Comic Power

    Tønder, Lars

    2014-01-01

    Inspired by the growing attention to the politics of comedy in the United States and elsewhere, this article asks what it would mean to think critically about relations of power mobilized through cheerfulness, humor, and laughter. The article shows that existing answers to this question are tainted...... by skepticism about the enduring contributions of comic acts, and it then goes on to suggest that we turn to an alternative trajectory in democratic theory, one that encourages us to focus on the empowering and pluralizing potential embedded in what I name “comic power.” The wager is that attention...... to the potential embedded in this power can give us new traction on the conditions of democracy more broadly understood. To show this, the article draws on two rarely paired resources—Spinoza’s philosophy of immanence and Dave Chappelle’s critique of racial discrimination—placing both of them in conversation...

  7. Solar Panel Maximum Power Point Tracker for Power Utilities

    Sandeep Banik,

    2014-01-01

    Full Text Available ―Solar Panel Maximum Power Point Tracker For power utilities‖ As the name implied, it is a photovoltaic system that uses the photovoltaic array as a source of electrical power supply and since every photovoltaic (PV array has an optimum operating point, called the maximum power point, which varies depending on the insolation level and array voltage. A maximum power point tracker (MPPT is needed to operate the PV array at its maximum power point. The objective of this thesis project is to build a photovoltaic (PV array Of 121.6V DC Voltage(6 cell each 20V, 100watt And convert the DC voltage to Single phase 120v,50Hz AC voltage by switch mode power converter‘s and inverter‘s.

  8. Power Down

    2008-01-01

    @@ Cai Wending and his colleague Xie Changsheng have been living out of a suitcase for the past two months.The pair,managers at a coal-fired power plant in Hunan Province,have been staying in a modest three-star hotel in Jincheng,a small city in Shanxi Province.They are not the only long-term residents of the hotel.Numerous power plant officials have been drawn to Jincheng from across China,all for the same purpose-to buy coal.

  9. Environment and power development

    Shahi, R.V. [Bombay Suburban Electric Supply Co. Ltd., Bombay (India)

    1995-12-31

    The two fastest growing economics in Asia, China and India, rely heavily on fossil fuel. The paper discusses the environmental implications of the inevitable increase in power generation and use, the principle sources of greenhouse gases, and the initiatives required to mitigate the known effects of developing and operating power plants. Greenhouse gas emission levels can be reduced substantially in the developing countries, towards global advantage, with least incremental cost. It is suggested that a system of greenhouse gas reduction credits needs to be institutionalized. A 5% increase in efficiency from present levels results in 15% reduction in CO{sub 2} emissions. The importance of conducting environmental impact assessments of proposed sites is stressed, along with the need to utilize clean coal technologies to reduce pollution from power plants. A system of environmental appraisal and auditing of power plants is advocated. Advances being made in utilization of ashes from power plants and the importance being placed on rehabilitation of people affected by them are mentioned. 1 fig.

  10. High Efficiency Power Converter for Low Voltage High Power Applications

    Nymand, Morten

    , and remote power generation for light towers, camper vans, boats, beacons, and buoys etc. A review of current state-of-the-art is presented. The best performing converters achieve moderately high peak efficiencies at high input voltage and medium power level. However, system dimensioning and cost are often...

  11. POWER FUNCTIONS

    王雷

    2008-01-01

    <正>A power function of degree n is a function of the form f(x)=ax~n.For large n,it appears that the graph coincide with the x-axis near the origin,but it does not;the graph actually touches the x—axis only at the origin.

  12. Power semiconductors

    Kubát, M

    1984-01-01

    The book contains a summary of our knowledge of power semiconductor structures. It presents first a short historic introduction (Chap. I) as well as a brief selection of facts from solid state physics, in particular those related to power semiconductors (Chap. 2). The book deals with diode structures in Chap. 3. In addition to fundamental facts in pn-junction theory, the book covers mainly the important processes of power structures. It describes the emitter efficiency and function of microleaks (shunts). the p +p and n + n junctions, and in particular the recent theory of the pin, pvn and p1tn junctions, whose role appears to be decisive for the forward mode not only of diode structures but also of more complex ones. For power diode structures the reverse mode is the decisive factor in pn-junction breakdown theory. The presentation given here uses engineering features (the multiplication factor M and the experimentally detected laws for the volume and surface of crystals), which condenses the presentation an...

  13. Power branding

    Chambers, A.

    1998-12-31

    For most of its century-long history, electricity was a natural monopoly, due in part to the excessive cost of the necessary infrastructure. In the past decade, however, politics have pushed the industry toward competition and consumer choice. At the same time, technology has been developed that allows consumers to choose their electricity supplier and to track the flow of power through the various grids and lines. In her new book, Power Branding, author and industry expert Ann Chambers examines marketing and branding of electricity -- what it is, how it`s done, what its benefits are for electric utilities, marketers, and even natural gas companies allied with the utilities. She surveys industry leaders who have already taken a dive into the ocean of marketing and offers lessons drawn from their experiences. She also takes a look at other formerly regulated industries -- airlines, telephone, natural gas -- and describes how their rebirth as free-market industries may affect the course of the electric utility industry`s experience. The contents include: Introduction; Basics of branding: Brand image; Value-added services; Southern Company; Duke Energy; UtiliCorp/EnergyOne/Aquila--big and brand; Engage energy; Florida Power and Light Co.; Enron; Convergence; Lessons from the natural gas industry; Lessons from other industries; Conclusion; Resources; Glossary of branding, marketing and Btu convergence; and Major federal legislation affecting the electric power industry.

  14. Power Play

    BRADLEY GARDNER

    2008-01-01

    @@ Bill Emmott's new book,Rivals:How the Power Struggle Between China,India and Japan Will Shape Our Next Decade,is an investigation of the problematic relationship between China,India,and Japan,as two of those countries begin to assert themselves on the world stage,and how the situation could result in all-out conflict.

  15. Powering up

    2008-01-01

    China building the world’s first third-generation nuclear power plants based on American technology Almost 30 years ago, a partial core meltdown occurred in one of the two nuclear reactors at Three Mile llsland Nuclear Generating Station in

  16. Power Shift

    2008-01-01

    @@ "We are entering a new era of world history: the end of Western domination and the arrival of the Asian century. The question is: will Washington wake up to this reality?" This is the central premise of Kishore Mahbubani's provocative new book The New Asian Hemisphere: The Irresistible Shift of Global Power to the East.

  17. 塔式太阳能热发电全寿命周期成本电价分析%Analysis of Life-cycle Levelized Cost of Electricity for Tower Solar Thermal Power

    李心; 赵晓辉; 李江烨; 李伟; 徐能; 黄文君

    2015-01-01

    Tower solar thermal power(STP)is one of the most promising techniques of renewable energy in the world,but its development has slowed down because of its high cost.A life-cycle calculation model is built to predict the levelized cost of electricity (LCOE) of tower STP plants in China,and the integrating factors,including construction cost,the electricity generation and the operation & maintenance costs,are considered one by one.This study focuses on the downward-trend of heliostats cost caused by various motivations,through a method of decomposition of the manufacturing costs into material, manufacturing and transport cost.The study shows that the LCOE is declined by the development of the motivations of production capacity,installed capacity and technical matter,and the installed capacity makes the most significant effect.%塔式太阳能热发电是全球新能源近年发展的新亮点之一,成本电价高是制约其发展的主要原因。文中给出了塔式太阳能热发电站成本电价计算的全寿命周期模型,并结合建造成本、运营维护成本及发电量的预测,对影响成本电价的因素逐一分析,测算了中国塔式太阳能热发电站的预期成本电价。重点从材料、加工和安装运输3个维度对定日镜成本的变化趋势进行了分析。计算结果表明,成本电价随产能规模、单机装机容量及技术工艺因素的发展而下降,其中产能规模作用最为明显。

  18. Quasi-PR Power Quality Control of NPC Three-level Grid-connected PV System%NPC三电平光伏并网准PR电能质量控制

    陈晖; 王睿宣; 孙玉坤; 张亮; 姚沼林; 黄永红

    2016-01-01

    The inverter circuit of grid-connected PV system and the parallel APF have many similarities in topological structure, operation mode and control method, based on this, a new kind of control method which can combine the reactive compensation and active filter with grid-connected PV power generation is put forward. Using FBD current detection method, the instantaneous reactive and harmonic current detection can be realized without complex Park transform ord-qtransform. Combining with the neutral point clamped (NPC) three-level quasi-PR control strategy, static error free tracking control of the alternating current signal in static coordinates can be realized. The control algorithm has been greatly simplified while the harmonic of grid current has been effectively reduced, at the same time, the robustness of the system has been enhanced. The simulation and experimental results show that the proposed control strategy can effectively suppress harmonics as well as achieve the compensation control of grid-connected PV generation and reactive compensation.%为提高光伏并网电能质量,基于光伏并网发电系统逆变主电路和并联型APF在拓扑结构、运行方式和控制方法上具有诸多相同点,提出一种将有源滤波和无功功率补偿与光伏并网发电相结合的新型控制方案。该方案利用 FBD 电流检测法,无需复杂的Park变换和d-q变换,即可实现瞬时谐波和无功电流的检测。结合中点箝位式(NPC)三电平准 PR 控制策略,即可完成对交变电流信号在静止坐标系下的无静差跟踪控制,在简化控制算法的同时大大减小了并网电流的谐波含量,且增强了系统的鲁棒性。仿真及实验结果表明,所提控制策略可有效地实现光伏并网发电和有源滤波及无功功率补偿的统一控制。

  19. 高功率MPCVD金刚石膜透波窗口材料制备研究%Synthesis of Diamond Film as Electromagnetic Window Material by an Ellipsoidal MPCVD Reactor at High Input Microwave Power Levels

    于盛旺; 刘艳青; 唐伟忠; 申艳艳; 贺志勇; 唐宾

    2012-01-01

    使用自行研制的椭球谐振腔式MPCVD装置,以H2-CH4为气源,在沉积功率8 kW条件下,对大面积金刚石膜透波窗口材料进行了制备研究.分别使用扫描电镜、Raman、分光光谱仪、热导率测试仪和空腔谐振法对金刚石膜的表面形貌、品质、光透过率、热导率和微波复介电常数等进行了表征及测试.实验结果表明,使用自行研制的椭球谐振腔式MPCVD装置,能够满足较高功率下高品质金刚石膜的快速沉积;抛光后的自支撑金刚石膜具有高的光学透过率和热导率,在23 ~ 36 GHz频率范围内微波介电损耗小于1×10-4,有着良好的微波介电性能,是较为理想的透波窗口材料.%Polycrystalline diamond film was grown using H2-CH4 as the source gas in a newly developed ellipsoidal MPCVD reactor at 8 kW microwave power levels. Surface morphology, quality, transmittance, thermal conductivity as well as complex permittivity of the diamond film were examined by scanning electron microscopy, Raman spectroscopy, spectrophotometer, thermal constant tester and cavity resonator method respectively. The result proved that the new ellipsoidal microwave plasma CVD reactor has the ability to deposit high quality diamond films at a high synthesis rate. After polished on both sides, the free-standing diamond film has high transmittance and thermal conductivity. At the same time the film has excellent microwave dielectric properties for complex permittivity less than 1 x 10-4 in the range of 23-36 GHz, this show the film is one of the perfect electromagnetic window materials.

  20. Economic Analysis of Cikaso Mini Hydro Power Plant as a CDM Project for Increasing IRR

    Irhan Febijanto

    2013-12-01

    Full Text Available Renewable energy fueled power generations are few developed by private sector in Indonesia. High-cost investment and low electricity selling price to PT PLN as a single buyer is main barriers for private sector to involve in the development of renewable energy fueled power generations. In this project, the economic feasibility of Mini Hydro Power Plant of Cikaso with capacity of 5.3 MW, located at Sukabumi Regency, West Java province was assessed. This project utilized revenue generated from carbon market to increase the economic feasibility. Procedure to register the project to United Nation for Climate Change Convention (UNFCCC as a Clean Development Mechanism project was explained in detail. Approved Consolidation Methodology (ACM 0002 Version 12.3.0 was used to calculate grid emission factor in Jawa-Bali-Madura the grid electricity system. It was calculated that the grid emission factor is 0.833 (t-CO2/MWh, and the carbon emission reduction generated for this project is 21,982 ton/year. From the analysis result, it can be proven that the additional revenue from carbon credit could increase the project IRR from 10.28% to 13.52%.

  1. Status of R&D activity for ITER ICRF power source system

    Mukherjee, Aparajita, E-mail: aparajita.mukherjee@iter-india.org [ITER-India, Institute for Plasma Research, Bhat, Gandhinagar–382428 (India); Trivedi, Rajesh; Singh, Raghuraj; Rajnish, Kumar; Machchhar, Harsha; Ajesh, P.; Suthar, Gajendra; Soni, Dipal; Patel, Manoj; Mohan, Kartik; Hari, J.V.S.; Anand, Rohit; Verma, Sriprakash; Agarwal, Rohit; Jha, Akhil [ITER-India, Institute for Plasma Research, Bhat, Gandhinagar–382428 (India); Kazarian, Fabienne; Beaumont, Bertrand [ITER Organization, CS 90 046, 13067 Sain-Paul-Les-Durance (France)

    2015-10-15

    Highlights: • R&D program to establish high power RF technology for ITER ICRF source is described. • R&D RF source is being developed using Diacrode & Tetrode technologies. • Test rig (3 MW/3600 s/35–65 MHz) simulating plasma load is developed. - Abstract: India is in-charge for the procurement of ITER Ion Cyclotron Resonance Frequency (ICRF) sources (1 Prototype + 8 series units) along with auxiliary power supplies and Local Control Unit. As there is no unique amplifier chain able to meet the output power specifications as per ITER requirement (2.5 MW per source at 35–65 MHz/CW/VSWR 2.0), two parallel three-stage amplifier chains along with a combiner circuit on the output side is considered. This kind of RF source will be unique in terms of its stringent specifications and building a first of its kind is always a challenge. An R&D phase has been initiated for establishing the technology considering single amplifier chain experimentation (1.5 MW/35–65 MHz/3600 s/VSWR 2.0) prior to Prototype and series production. This paper presents the status of R&D activity to resolve technological challenges involved and various infrastructures developed at ITER-India lab to support such operation.

  2. Output power control for large wind power penetration in small power system

    Senjyu, Tomonobu; Kaneko, Toshiaki; Uehara, Akie; Yona, Atsushi; Sekine, Hideomi [University of the Ryukyus, 1 Senbaru, Nishihara-cho, Nakagami, Okinawa 903-0213 (Japan); Kim, Chul-Hwan [Sungkyunkwan University, Suwon 440-746 (Korea)

    2009-11-15

    Nowadays, wind turbine generator (WTG) is increasingly required to provide control capabilities regarding output power. Under this scenario, this paper proposes an output power control of WTG using pitch angle control connected to small power systems. By means of the proposed method, output power control of WTG considering states of power system becomes possible, and in general both conflicting objectives of output power leveling and acquisition power increase are achieved. In this control approach, WTG is given output power command by fuzzy reasoning which has three inputs for average wind speed, variance of wind speed, and absolute average of frequency deviation. Since fuzzy reasoning is used, it is possible to define output power command corresponding to wind speed condition and changing capacity of power system momentarily. Moreover, high performance pitch angle control based on output power command is achieved by generalized predictive control (GPC). The simulation results by using actual detailed model for wind power system show the effectiveness of the proposed method. (author)

  3. How Much DC Power is Necessary

    2010-04-01

    must transform essentially all of the available AC power to DC, including all of the power for the ship propulsion drive. This approach by the...in Fig. 1 convert the AC source power to DC and energize the associated DC busses. At the power levels anticipated, i.e., for ship propulsion load...for a ship propulsion application. We begin by assuming that the variable frequency power electronics associated with the rotor will only deliver

  4. Unsupervised Power Profiling for Mobile Devices

    Kjærgaard, Mikkel Baun; Blunck, Henrik

    2012-01-01

    Today, power consumption is a main limitation for mobile phones. To minimizethe power consumption of popular and traditionally power-hungry location-basedservices requires knowledge of how individual phone features consume power, sothat those features can be utilized intelligently for optimalpower savings while at the same time maintaining good quality of service. Thispaper proposes an unsupervised API-level method for power profiling mobile phones based on genetic algorithms.The method enabl...

  5. Suntech Power

    BRAKLEY GARDNER

    2008-01-01

    @@ Why the new US president could provide a boost for China's largest solar firm Back in the glory days of China investing, Suntech Power (尚德太阳能电力), China's largest solar com-pany, benefited from both inves-tor interest during China's stock market boom, and the growing demand for solar technologies worldwide, as governments be-gan implementing a raft of new measures providing assistance to renewable energy companies.

  6. Cyber Power

    2010-05-01

    attributed to “patriotic hackers” in Russia who were offended by Estonia’s movement of a World War II monument to Soviet soldiers. In 2008, shortly...internet to mobilize Chinese students to demonstrate against Japan when its officials took positions that offended Chinese views of the 1930s...reduction of power differentials among them. Anyone from a teen age hacker to a major modern government can do damage in cyber space, and as the famous New

  7. BRICS Power

    2011-01-01

    When Goldman Sachs economist Jim O’Neill coined the acronym BRIC to describe collectively Brazil,Russia,India and China,the world mainly regarded it as one of the easy-come,easy-go terms in economics.A decade later,O’Neill’s concept is not forgotten.It is successfully playing an historic role in representing the shift in global economic power away

  8. Optimal Power Flow Pursuit

    Dall' Anese, Emiliano

    2016-08-01

    Past works that focused on addressing power-quality and reliability concerns related to renewable energy resources (RESs) operating with business-as-usual practices have looked at the design of Volt/VAr and Volt/Watt strategies to regulate real or reactive powers based on local voltage measurements, so that terminal voltages are within acceptable levels. These control strategies have the potential of operating at the same time scale of distribution-system dynamics, and can therefore mitigate disturbances precipitated fast time-varying loads and ambient conditions; however, they do not necessarily guarantee system-level optimality, and stability claims are mainly based on empirical evidences. On a different time scale, centralized and distributed optimal power flow (OPF) algorithms have been proposed to compute optimal steady-state inverter setpoints, so that power losses and voltage deviations are minimized and economic benefits to end-users providing ancillary services are maximized. However, traditional OPF schemes may offer decision making capabilities that do not match the dynamics of distribution systems. Particularly, during the time required to collect data from all the nodes of the network (e.g., loads), solve the OPF, and subsequently dispatch setpoints, the underlying load, ambient, and network conditions may have already changed; in this case, the DER output powers would be consistently regulated around outdated setpoints, leading to suboptimal system operation and violation of relevant electrical limits. The present work focuses on the synthesis of distributed RES-inverter controllers that leverage the opportunities for fast feedback offered by power-electronics interfaced RESs. The overarching objective is to bridge the temporal gap between long-term system optimization and real-time control, to enable seamless RES integration in large scale with stability and efficiency guarantees, while congruently pursuing system-level optimization objectives. The

  9. 提高供电企业内训师培训水平的措施探讨%To improve the level of power supply enterprise internal trainers training measures

    任宇春; 任道玉

    2016-01-01

    随着我国电力企业的不断发展,需要具有高素质的人才投身于这项工作。然而现阶段我国电力企业内训师培训机制还不够完善。本文对我国供电企业内训师的现状进行了分析,并且就其存在的问题提出了一些改进建议。%With thecontinuous development of China's power enterprises,the need for high-quality personnel to join in this work.However,the internal trainer training mechanism of China's power enterprises at this stage is still not perfect.In this paper,the status quo of China power supply enterprises internal trainers are analyzed,and the existing problems put forward some suggestions for improvement.

  10. Enhanced inverse spin Hall contribution at high microwave power levels in La{sub 0.67}Sr{sub 0.33}MnO{sub 3}/SrRuO{sub 3} epitaxial bilayers

    Haidar, S. M., E-mail: haidar@imr.tohoku.ac.jp; Lustikova, J. [Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan); Shiomi, Y. [Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan); Spin Quantum Rectification Project, ERATO, Japan Science and Technology Agency, Sendai 980-8577 (Japan); Saitoh, E. [Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan); Spin Quantum Rectification Project, ERATO, Japan Science and Technology Agency, Sendai 980-8577 (Japan); WPI Advanced Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan); Advanced Science Research Center, Japan Atomic Energy Agency, Tokai 319-1195 (Japan)

    2015-10-12

    We have investigated microwave power dependence of dc voltage generated upon ferromagnetic resonance in a La{sub 0.67}Sr{sub 0.33}MnO{sub 3}/SrRuO{sub 3} epitaxial bilayer film at room temperature. With increasing microwave power above ∼75 mW, the magnitude of the voltage signal decreases as the sample temperature approaches the Curie temperature of La{sub 0.67}Sr{sub 0.33}MnO{sub 3} due to heating effects. By analyzing the dependence of the voltage signal on the direction of the magnetic field, we show that with increasing microwave power the contribution from the inverse spin Hall effect becomes more dominant than that from the anisotropic magnetoresistance effect.

  11. Public power`s new reality

    NONE

    1995-12-31

    The paper describes a system developed to measure investor-owned and public power utilities` individual level of risk from increased competition. The system was used to rank 74 utilities. The Fitch Competitive Indicator (FCI) evaluates a utility`s current competitive position and compares it to other energy providers in the same US region. Energy providers used for comparison include electric utilities, non-utility generators, self-generation, and other potential alternatives. Factors used to determine the FCI include quality of utility management, rate competitiveness, plant performance, cost of production, regulation, financial ratios, legal issues, and demographics.

  12. A Tariff for Reactive Power

    Kueck, John D [ORNL; Kirby, Brendan J [ORNL; Li, Fangxing [ORNL; Tufon, Christopher [Pacific Gas and Electric Company; Isemonger, Alan [California Independent System Operator

    2008-07-01

    Two kinds of power are required to operate an electric power system: real power, measured in watts, and reactive power, measured in volt-amperes reactive or VARs. Reactive power supply is one of a class of power system reliability services collectively known as ancillary services, and is essential for the reliable operation of the bulk power system. Reactive power flows when current leads or lags behind voltage. Typically, the current in a distribution system lags behind voltage because of inductive loads such as motors. Reactive power flow wastes energy and capacity and causes voltage droop. To correct lagging power flow, leading reactive power (current leading voltage) is supplied to bring the current into phase with voltage. When the current is in phase with voltage, there is a reduction in system losses, an increase in system capacity, and a rise in voltage. Reactive power can be supplied from either static or dynamic VAR sources. Static sources are typically transmission and distribution equipment, such as capacitors at substations, and their cost has historically been included in the revenue requirement of the transmission operator (TO), and recovered through cost-of-service rates. By contrast, dynamic sources are typically generators capable of producing variable levels of reactive power by automatically controlling the generator to regulate voltage. Transmission system devices such as synchronous condensers can also provide dynamic reactive power. A class of solid state devices (called flexible AC transmission system devices or FACTs) can provide dynamic reactive power. One specific device has the unfortunate name of static VAR compensator (SVC), where 'static' refers to the solid state nature of the device (it does not include rotating equipment) and not to the production of static reactive power. Dynamic sources at the distribution level, while more costly would be very useful in helping to regulate local voltage. Local voltage regulation would

  13. Manufacturable Tri-Stack AlSb/InAs HEMT Low-Noise Amplifiers Using Wafer-Level-Packaging Technology for Light-Weight and Ultralow-Power Applications

    2009-05-01

    CA, USA yeong-chang.chou@ngc.com J. B. Boos, B. R. Bennett, and N. A. Papanicolaou Naval Research Laboratory Washington DC, USA boos...introduce negative factors to affect RF yield and performance of power amplifiers, switches, and phase shifters. Figure 7 shows the on-wafer rf...Barsky, J. B. Boos, B. R. Bennett, J. L. Lee, N. A. Papanicolaou et al., “Metamorphic AlSb/InAs HEMTs for low-power, high-speed electronics,” the

  14. Economic Operation of Power Systems with Significant Wind Power Penetration

    Farashbashi-Astaneh, Seyed-Mostafa

    This dissertation addresses economic operation of power systems with high penetration of wind power. Several studies are presented to address the economic operation of power systems with high penetration of variable wind power. The main concern in such power systems is high variability...... level should be economic and can be a provided by different tools such as developing new reserve scheduling techniques, demand response, using storage units, facilitating the capacity of cross-border interconnections and so on. These subjects are addressed in this PhD dissertation. In the first study...... (and thus power system security is enhanced). The optimal charging scheme of Eclectic Vehicles (EVs) in a distribution feeder is then studied considering the proposed pricing scheme. A formulation is then proposed for optimal reserve scheduling considering the role of reserve provision scenarios from...

  15. High Efficiency Power Converter for Low Voltage High Power Applications

    Nymand, Morten

    , and remote power generation for light towers, camper vans, boats, beacons, and buoys etc. A review of current state-of-the-art is presented. The best performing converters achieve moderately high peak efficiencies at high input voltage and medium power level. However, system dimensioning and cost are often......The topic of this thesis is the design of high efficiency power electronic dc-to-dc converters for high-power, low-input-voltage to high-output-voltage applications. These converters are increasingly required for emerging sustainable energy systems such as fuel cell, battery or photo voltaic based...... determined by the performance at the system worst case operating point which is usually at minimum input voltage and maximum power. Except for the non-regulating V6 converters, all published solutions exhibit a very significant drop in conversion efficiency at minimum input voltage and maximum output power...

  16. Space power development impact on technology requirements

    Cassidy, J. F.; Fitzgerald, T. J.; Gilje, R. I.; Gordon, J. D.

    1986-01-01

    The paper is concerned with the selection of a specific spacecraft power technology and the identification of technology development to meet system requirements. Requirements which influence the selection of a given technology include the power level required, whether the load is constant or transient in nature, and in the case of transient loads, the time required to recover the power, and overall system safety. Various power technologies, such as solar voltaic power, solar dynamic power, nuclear power systems, and electrochemical energy storage, are briefly described.

  17. Unsupervised Power Profiling for Mobile Devices

    Kjærgaard, Mikkel Baun; Blunck, Henrik

    power savings while at the same time maintaining good quality of service. This paper proposes an unsupervised API-level method for power profiling mobile phones based on genetic algorithms. The method enables accurate profiling of the power consumption of devices and thereby provides the information......Today, power consumption is a main limitation for mobile phones. To minimize the power consumption of popular and traditionally power-hungry location-based services requires knowledge of how individual phone features consume power, so that those features can be utilized intelligently for optimal...

  18. Unsupervised Power Profiling for Mobile Devices

    Kjærgaard, Mikkel Baun; Blunck, Henrik

    2011-01-01

    power savings while at the same time maintaining good quality of service. This paper proposes an unsupervised API-level method for power profiling mobile phones based on genetic algorithms. The method enables accurate profiling of the power consumption of devices and thereby provides the information......Today, power consumption is a main limitation for mobile phones. To minimize the power consumption of popular and traditionally power-hungry location-based services requires knowledge of how individual phone features consume power, so that those features can be utilized intelligently for optimal...

  19. Power plant siting

    Winter, J.V.; Conner, D.A.

    1978-01-01

    Just to keep up with expected demand, the US will need over 500 new power generation units by 1985. Where these power plants will be located is the subject of heated debate among utility officials, government leaders, conservationists, concerned citizens and a multitude of special interest groups. This book offers a balanced review of all of the salient factors that must be taken into consideration in selecting power plant locations. To deal with this enormously complex subject, the authors (1) offer a general overview of the history and reasoning behind present legislation on the state and national levels; (2) describe the many different agencies that have jurisdiction in power plant location, from local water authorities and city councils to state conservation boards and the Nuclear Regulatory Commission; and (3) include a state-by-state breakdown of siting laws, regulations and present licensing procedures. Architects, engineers, contractors, and others involved in plant construction and site evaluation will learn of the trade-offs that must be made in balancing the engineering, economic, and environmental impacts of plant location. The book covers such areas as availability of water supplies for generation or cooling; geology, typography, and demography of the proposed site; and even the selection of the fuel best suited for the area. Finally, the authors examine the numerous environmental aspects of power plant siting.

  20. 《往复式内燃机排气消声器测量方法声压法声功率级和插入损失及功率损失比》标准解读%Interpretation of the Standard Reciprocating Internal Combustion Engines-Measurement Method for Exhaust Silencers-Sound Power Level of Exhaust Noise and Insertion Loss Using Sound Pressure and Power Loss Ratio

    胡爱华; 袁卫平; 吕宫

    2015-01-01

    This paper gives an instruction to ISO 15619:2013, Reciprocating intrnal combustion engines -Measurement method for exhaust silencers-Sound power level of exhaust noise and insertion loss using sound pressure and power loss ratio. It also introduces the use of the standard, specifying the parameters and the uncertainty of the measurement, and discusses some key technologies, providing reference for the application in China.%本文对ISO 15619:2013《往复式内燃机排气消声器测量方法声压法声功率级和插入损失及功率损失比》标准进行了解读,介绍了标准的用途、测量参数、不确定度和关键技术,为相关人员使用本国际标准提供借鉴。

  1. High impact data visualization with Power View, Power Map, and Power BI

    Aspin, Adam

    2014-01-01

    High Impact Data Visualization with Power View, Power Map, and Power BI helps you take business intelligence delivery to a new level that is interactive, engaging, even fun, all while driving commercial success through sound decision-making. Learn to harness the power of Microsoft's flagship, self-service business intelligence suite to deliver compelling and interactive insight with remarkable ease. Learn the essential techniques needed to enhance the look and feel of reports and dashboards so that you can seize your audience's attention and provide them with clear and accurate information. Al

  2. Leveled cost of the generation in a power station of combined cycle with integrated gas producer (CCGI); Costo nivelado de la generacion en una central de ciclo combinado con gasificador integrado (CCGI)

    Hiriart Le Bert, Gerardo [Comision Federal de Electricidad (CFE), (Mexico); Beltran Mora, Hector [Facultad de Ingenieria, Universidad Nacional Autonoma de Mexico, Mexico, D.F. (Mexico)

    2004-06-15

    A brief description of a combined cycle power station that uses synthesis gas, better known as CCGI, is presented. The costs of the initial investment of several plants of this type, that have been described in literature, are analyzed and the predictions that different experts do on the costs that are expected in the near future are reviewed. Also the maintenance expenses that would be expected during the normal operation and the main maintenance are examined. The availability factors that reasonably must be considered based on the recent experiences are analyzed. Afterwards the sense which that the plant factor has in one of natural gas and one of synthesis, where generally are used as base plant. The costs of the different fuels that can be used in a CCGI are examined. Finally the leveled cost of the energy for both cases is calculated and the sensitivity of both to the cost of the respective fuels is examined. The result is presented in graphical form to show in a first attempt, the circumstances under which one or another technology could be preferable. It is made clear that the data used in this brief study are the best reasoned estimation and in no way they must be considered as definitive, in special in those of investment and maintenance of the CCGI where the operation history is still short. [Spanish] Se presenta una breve descripcion de una Central de Ciclo Combinado que utiliza Gas de Sintesis o mejor conocidas como CCGI. Se analizan los costos de la inversion inicial de varias plantas de este tipo que han sido descritas en la literatura y se resenan las predicciones que hacen diferentes expertos sobre los costos que se esperan para el futuro cercano. Tambien se examinan los gastos de mantenimiento que se esperarian durante la operacion normal y durante los mantenimientos mayores. Se analizan los factores de disponibilidad que razonablemente deben considerarse, basados en las experiencias recientes. Luego se discute el sentido que tiene el factor de

  3. Power electronics a first course

    Mohan, Ned

    2011-01-01

    Author Ned Mohan has been a leader in EES education and research for decades. His three-book series on Power Electronics focuses on three essential topics in the power sequence based on applications relevant to this age of sustainable energy such as wind turbines and hybrid electric vehicles. The three topics include power electronics, power systems and electric machines. Key features in the first Edition build on Mohan's successful MNPERE texts; his systems approach which puts dry technical detail in the context of applications; and substantial pedagogical support including PPT's, video clips, animations, clicker questions and a lab manual. It follows a top-down systems-level approach to power electronics to highlight interrelationships between these sub-fields. It's intended to cover fundamental and practical design. This book also follows a building-block approach to power electronics that allows an in-depth discussion of several important topics that are usually left. Topics are carefully sequenced to mai...

  4. EU Power Balance

    2004-01-01

    @@ Intense clashes of interests and collusion of ideas sprang up incessantly among nations over upward sovereignty transfer, interests distribution and maintenance of parity among partners in the course of economic integration. Disparities in size, territory, national strength and development level conceivably often led to tensions and even crises over power distribution. So EU history can be described as one of crises or crisis settlement through reaching a new equilibrium, a significant process for sustained EU stability.

  5. Applied Research on Medium and Low Power Level Dual-CO2-Laser Cutting Machine%中低功率双CO2激光切割机的开发与应用

    甘家梁; 孙红安; 唐海昌

    2011-01-01

    Cutting principles of high-power single-CO2-laser cutting and low-power dual-CO2-laser cutting are discussed. Non-metallic materials such as wood die-boards are cut by using these two laser cutting techniques. The dependences of cutting depth and seam shape on laser power and cutting speed are analyzed. The results show that cutting wood die-boards with low-power dual-CO2-laser cutting has many advantages over high-power single-laser-head cutting in the manufacturing costs, operating costs, cutting precision and seam shape.%研究了大功率单CO2激光切割机和小功率双CO2激光切割机的切割原理,分析了在用这两种形式的激光切割机切割非金属材料木质模切板时,激光功率、切割速度与切割深度、切割的缝形缝宽之间的关系.试验结果表明,用中小功率双CO2激光切割机切割非金属木质板材,无论是设备的制造成本、运行成本,还是切割的精度和缝形缝宽,同用大功率单CO2激光头切割机相比有很多优势.

  6. Smart Power Supply for Battery-Powered Systems

    Krasowski, Michael J.; Greer, Lawrence; Prokop, Norman F.; Flatico, Joseph M.

    2010-01-01

    A power supply for battery-powered systems has been designed with an embedded controller that is capable of monitoring and maintaining batteries, charging hardware, while maintaining output power. The power supply is primarily designed for rovers and other remote science and engineering vehicles, but it can be used in any battery alone, or battery and charging source applications. The supply can function autonomously, or can be connected to a host processor through a serial communications link. It can be programmed a priori or on the fly to return current and voltage readings to a host. It has two output power busses: a constant 24-V direct current nominal bus, and a programmable bus for output from approximately 24 up to approximately 50 V. The programmable bus voltage level, and its output power limit, can be changed on the fly as well. The power supply also offers options to reduce the programmable bus to 24 V when the set power limit is reached, limiting output power in the case of a system fault detected in the system. The smart power supply is based on an embedded 8051-type single-chip microcontroller. This choice was made in that a credible progression to flight (radiation hard, high reliability) can be assumed as many 8051 processors or gate arrays capable of accepting 8051-type core presently exist and will continue to do so for some time. To solve the problem of centralized control, this innovation moves an embedded microcontroller to the power supply and assigns it the task of overseeing the operation and charging of the power supply assets. This embedded processor is connected to the application central processor via a serial data link such that the central processor can request updates of various parameters within the supply, such as battery current, bus voltage, remaining power in battery estimations, etc. This supply has a direct connection to the battery bus for common (quiescent) power application. Because components from multiple vendors may have

  7. Power Ramp Limitation capabilities of Large PV Power Plants with Active Power Reserves

    Bogdan, Craciun; Kerekes, Tamas; Sera, Dezso

    2017-01-01

    Power Ramp Limitation (PRL) is likely to become a requirement for large scale photovoltaic power plants (LPVPPs) in order to allow the increase of PV penetration levels. Especially in islands with reduced inertia capability, this problem is more stringent: high power ramp can be caused by either...... fast irradiance changes or other participant generators for example wind power, or loads. In order to compensate for the power mismatch, LPVPPs must use Active Power Reserve (APR), by either curtailment or auxiliary storage. The paper proposes a PRL control structure for dynamic APR sizing...... area of LPVPPs acts as filter against fast irradiance changes, the study reveals also the required plant size for which auxiliary storage is no longer needed in order to comply with PRL requirements – an important economical aspect....

  8. Ion cyclotron resonance heating systems upgrade toward high power and CW operations in WEST

    Hillairet, Julien; Zhao, Yanping; Bernard, Jean-Michel; Song, Yuntao; Argouarch, Arnaud; Berger-By, Gilles; Charabot, Nicolas; Chen, Gen; Chen, Zhaoxi; Colas, Laurent; Delaplanche, Jean-Marc; Dumortier, Pierre; Durodié, Frédéric; Ekedahl, Annika; Fedorczak, Nicolas; Ferlay, Fabien; Goniche, Marc; Hatchressian, Jean-Claude; Helou, Walid; Jacquot, Jonathan; Joffrin, Emmanuel; Litaudon, Xavier; Lombard, Gilles; Maggiora, Riccardo; Magne, Roland; Milanesio, Daniele; Patterlini, Jean-Claude; Prou, Marc; Verger, Jean-Marc; Volpe, Robert; Vulliez, Karl; Wang, Yongsheng; Winkler, Konstantin; Yang, Qingxi; Yuan, Shuai

    2016-01-01

    The design of the WEST (Tungsten-W Environment in Steady-state Tokamak) Ion cyclotron resonance heating antennas is based on a previously tested conjugate-T Resonant Double Loops prototype equipped with internal vacuum matching capacitors. The design and construction of three new WEST ICRH antennas are being carried out in close collaboration with ASIPP, within the framework of the Associated Laboratory in the fusion field between IRFM and ASIPP. The coupling performance to the plasma and the load-tolerance have been improved, while adding Continuous Wave operation capability by introducing water cooling in the entire antenna. On the generator side, the operation class of the high power tetrodes is changed from AB to B in order to allow high power operation (up to 3 MW per antenna) under higher VSWR (up to 2:1). Reliability of the generators is also improved by increasing the cavity breakdown voltage. The control and data acquisition system is also upgraded in order to resolve and react on fast events, such a...

  9. Ion cyclotron resonance heating systems upgrade toward high power and CW operations in WEST

    Hillairet, Julien, E-mail: julien.hillairet@cea.fr; Mollard, Patrick; Bernard, Jean-Michel; Argouarch, Arnaud; Berger-By, Gilles; Charabot, Nicolas; Colas, Laurent; Delaplanche, Jean-Marc; Ekedahl, Annika; Fedorczak, Nicolas; Ferlay, Fabien; Goniche, Marc; Hatchressian, Jean-Claude; Helou, Walid; Jacquot, Jonathan; Joffrin, Emmanuel; Litaudon, Xavier; Lombard, Gilles; Magne, Roland; Patterlini, Jean-Claude [CEA, IRFM, F-13108 Saint Paul-lez-Durance (France); and others

    2015-12-10

    The design of the WEST (Tungsten-W Environment in Steady-state Tokamak) Ion cyclotron resonance heating antennas is based on a previously tested conjugate-T Resonant Double Loops prototype equipped with internal vacuum matching capacitors. The design and construction of three new WEST ICRH antennas are being carried out in close collaboration with ASIPP, within the framework of the Associated Laboratory in the fusion field between IRFM and ASIPP. The coupling performance to the plasma and the load-tolerance have been improved, while adding Continuous Wave operation capability by introducing water cooling in the entire antenna. On the generator side, the operation class of the high power tetrodes is changed from AB to B in order to allow high power operation (up to 3 MW per antenna) under higher VSWR (up to 2:1). Reliability of the generators is also improved by increasing the cavity breakdown voltage. The control and data acquisition system is also upgraded in order to resolve and react on fast events, such as ELMs. A new optical arc detection system comes in reinforcement of the V{sub r}/V{sub f} and SHAD systems.

  10. Design of Front Current Sampling Three-level Active Power Filter%电流采样前移三电平有源电力滤波器的设计

    康劲松; 卢文建

    2012-01-01

    The structures, principles of traditional active power filter (APF) and PWM rectifier were researched respectively. The similarities and differences between their basic functions, topologies and control strategies were analyzed. According to their similarities, some changes and improvement in topologies of PWM rectifier were made to acquire the functions and features of an active power filter. This active power filter didn't need to sample the load current, but moved the current sampling point to the network side and took the corresponding space vector algorithm to ensure the network side with ideal current. Through establishing the model in Madab/Simulink, simulation results compared with the original APF have shown that the new structure of APF is effective.%文中分别对传统的有源电力滤波器(ActivePowerFilter,APF)和PWM(Pulse—widthModulation)整流器结构和原理进行研究,分析了它们基本功能、主电路拓扑结构、控制特性及策略的异同。根据二者的相似性对PWM整流器的拓扑结构加以转换和改进,使其衍生出具有有源电力滤波器的功能和特性。该有源电力滤波器不需要对负载的电流进行采样,而是将电流采样点前移到网侧,并通过相应的空间矢量算法以保证网侧具有较理想的电流。所得结论经过Matlab/Sirnulink仿真后,证实该有源电力滤波器结构的有效性。

  11. Power optics

    Apollonov, V V [A M Prokhorov General Physics Institute, Russian Academy of Sciences, Moscow (Russian Federation)

    2014-02-28

    By using the theory we developed in the early 1970s, a broad range of phenomena is considered for an optical surface of a solid body that is exposed to radiation arbitrarily varying in time and producing temperature fields, thermoelastic stresses and thermal deformations on the surface layer. The examination is based on the relations (which are similar to Duhamel's integral formula from the theory of heat conduction) between the quantities characterising the thermal stress state in any nonstationary regimes of energy input into a solid. A peculiar feature of the analysis of the thermal stress state in this case consists in the fact that this relation comprises time as a parameter, which in turn is a consequence of incoherence of the quasi-stationary problem of thermoelasticity. This phenomenon is particularly important for the optics of high-power, high-pulse repetition rate lasers, which are being actively developed. In the review, we have recently published in Laser Physics, the thermal stress state of a solid is analysed. In this state, time is treated as an independent variable used in differentiation. Such an approach greatly reduces the applicability of the method. The review published contains data on the use of capillary porous structures made of various materials with different degrees of the surface development. Moreover, such structures can be efficiently employed to increase the heat exchange at a temperature below the boiling point of the coolant. In the present review we discuss the dependences of the limiting laser intensities on the duration of a pulse or a pulse train, corresponding to the three stages of the state of the reflecting surface and leading to unacceptable elastic deformations of the surface, to the plastic yield of the material accompanied by the formation of residual stresses and to the melting of the surface layer. We also analyse the problem of heat exchange in the surface layer with a liquid metal coolant pumped through it

  12. Power optics

    Apollonov, V. V.

    2014-02-01

    By using the theory we developed in the early 1970s, a broad range of phenomena is considered for an optical surface of a solid body that is exposed to radiation arbitrarily varying in time and producing temperature fields, thermoelastic stresses and thermal deformations on the surface layer. The examination is based on the relations (which are similar to Duhamel's integral formula from the theory of heat conduction) between the quantities characterising the thermal stress state in any nonstationary regimes of energy input into a solid. A peculiar feature of the analysis of the thermal stress state in this case consists in the fact that this relation comprises time as a parameter, which in turn is a consequence of incoherence of the quasi-stationary problem of thermoelasticity. This phenomenon is particularly important for the optics of high-power, high-pulse repetition rate lasers, which are being actively developed. In the review, we have recently published in Laser Physics, the thermal stress state of a solid is analysed. In this state, time is treated as an independent variable used in differentiation. Such an approach greatly reduces the applicability of the method. The review published contains data on the use of capillary porous structures made of various materials with different degrees of the surface development. Moreover, such structures can be efficiently employed to increase the heat exchange at a temperature below the boiling point of the coolant. In the present review we discuss the dependences of the limiting laser intensities on the duration of a pulse or a pulse train, corresponding to the three stages of the state of the reflecting surface and leading to unacceptable elastic deformations of the surface, to the plastic yield of the material accompanied by the formation of residual stresses and to the melting of the surface layer. We also analyse the problem of heat exchange in the surface layer with a liquid metal coolant pumped through it. The

  13. New power policy

    Sahai, I.M. [ed.] [Power Finance Corp., New Delhi (India)

    1997-04-01

    The federal government in India announced in December 1996 its policy for the Indian power sector, including the scope for further private investment. Called the Common Minimum National Action Plan for Power (the Plan), it was announced less than six months after the new government took office in June 1996. The Plan`s draft was formulated after extensive discussion between the federal and state governments, including two meetings with the state chief ministers and consultations between the 13 political parties which form the ruling coalition at the federal level. Not all suggestions found favor, and only those on which there was a broad agreement or consensus were included, hence the Common Minimum Action Plan. The Plan builds on the policies of the previous government, combined with the recent experience and the feedback the government received from various players in the field, including independent power producers (IPP), financial institutions and multilateral institutions. The Plan follows up on the policies already under implementation. It was clear that to get adequate response from private promoters, power sector reforms - structural and operational - were needed. The difficulties faced by IPP`s in project approval will be tackled through simplification of the procedures, delegation of power from federal agencies to state government and better fuel linkage for thermal plants. There is an emphasis on better use of installed capacities and on faster-track projects. Priority will be given to hydropower, though a detailed policy must evolve. The northeast region, with considerable hydropower potential, will be given special attention. The entry of private investment in the power sector will be carried forward allowing participation in transmission and distribution, too.

  14. Triglyceride level

    ... this page: //medlineplus.gov/ency/article/003493.htm Triglyceride level To use the sharing features on this page, please enable JavaScript. The triglyceride level is a blood test to measure the ...

  15. Wind power integration into the automatic generation control of power systems with large-scale wind power

    Abdul Basit

    2014-10-01

    Full Text Available Transmission system operators have an increased interest in the active participation of wind power plants (WPP in the power balance control of power systems with large wind power penetration. The emphasis in this study is on the integration of WPPs into the automatic generation control (AGC of the power system. The present paper proposes a coordinated control strategy for the AGC between combined heat and power plants (CHPs and WPPs to enhance the security and the reliability of a power system operation in the case of a large wind power penetration. The proposed strategy, described and exemplified for the future Danish power system, takes the hour-ahead regulating power plan for generation and power exchange with neighbouring power systems into account. The performance of the proposed strategy for coordinated secondary control is assessed and discussed by means of simulations for different possible future scenarios, when wind power production in the power system is high and conventional production from CHPs is at a minimum level. The investigation results of the proposed control strategy have shown that the WPPs can actively help the AGC, and reduce the real-time power imbalance in the power system, by down regulating their production when CHPs are unable to provide the required response.

  16. On modular Galois representations modulo prime powers

    Chen, Imin; Kiming, Ian; Wiese, Gabor

    2013-01-01

    . These notions of modularity are relative to a fixed level M. Using results of Hida we display a level-lowering result ("stripping-of-powers of p away from the level"): A mod pm strongly modular representation of some level Npr is always dc-weakly modular of level N (here, N is a natural number not divisible...

  17. Structural vulnerability assessment of electric power grids

    Koç, Y.; Warnier, M.; Kooij, R.E.; Brazier, F.

    2014-01-01

    Cascading failures are the typical reasons of blackouts in power grids. The grid topology plays an important role in determining the dynamics of cascading failures in power grids. Measures for vulnerability analysis are crucial to assure a higher level of robustness of power grids. Metrics from Comp

  18. Methodology for Assessment of Inertial Response from Wind Power Plants

    Altin, Müfit; Teodorescu, Remus; Bak-Jensen, Birgitte;

    2012-01-01

    High wind power penetration levels result in additional requirements from wind power in order to improve frequency stability. Replacement of conventional power plants with wind power plants reduces the power system inertia due to the wind turbine technology. Consequently, the rate of change...

  19. 电力营销信息系统与电话专网系统在基层供电单位中的应用研究%Study on the Application of Power Marketing Information System and Network Telephone System at the Grassroots Level in the Power Supply Unit

    党瑞; 贾嘉瑞

    2015-01-01

    The main composition of electric power marketing information system and the telephone network system were studied through the construction of electric power marketing information system, to solve the power supply business station users access information network and power supply business station between private telephone exchange bottleneck problem, so as to enhance the power supply operating station information access, to speed up the pace of information construction of villages and towns.%文章主要对电力营销信息系统与电话专网系统的组成进行了研究,通过电力营销信息系统的建设,解决供电营业站用户访问信息内网和供电营业站之间专网电话互通的瓶颈问题,从而提升了供电营业站的信息访问能力,加快乡镇信息化建设步伐。

  20. Power management system

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

    2007-10-02

    A method of managing power resources for an electrical system of a vehicle may include identifying enabled power sources from among a plurality of power sources in electrical communication with the electrical system and calculating a threshold power value for the enabled power sources. A total power load placed on the electrical system by one or more power consumers may be measured. If the total power load exceeds the threshold power value, then a determination may be made as to whether one or more additional power sources is available from among the plurality of power sources. At least one of the one or more additional power sources may be enabled, if available.

  1. POWER GRID RELIABILITY AND SECURITY

    Bose, Anjan; Venkatasubramanian, Vaithianathan; Hauser, Carl; Bakken, David; Anderson, David; Zhao, Chuanlin; Liu, Dong; Yang, Tao; Meng, Ming; Zhang, Lin; Ning, Jiawei; Tashman, Zaid

    2014-09-30

    This project has led to the development of a real-time simulation platform for electric power grids called Grid Simulator or GridSim for simulating the dynamic and information network interactions of large- scale power systems. The platform consists of physical models of power system components including synchronous generators, loads and control, which are simulated using a modified commercial power simulator namely Transient Stability Analysis Tool (TSAT) [1] together with data cleanup components, as well as an emulated substation level and wide-area power analysis components. The platform also includes realistic representations of communication network middleware that can emulate the real-time information flow back and forth between substations and control centers in wide-area power systems. The platform has been validated on a realistic 6000-bus model of the western American power system. The simulator GridSim developed in this project is the first of its kind in its ability to simulate real-time response of large-scale power grids, and serves as a cost effective real-time stability and control simulation platform for power industry.

  2. Power grid reliability and security

    Bose, Anjan [Washington State Univ., Pullman, WA (United States); Venkatasubramanian, Vaithianathan [Washington State Univ., Pullman, WA (United States); Hauser, Carl [Washington State Univ., Pullman, WA (United States); Bakken, David [Washington State Univ., Pullman, WA (United States); Anderson, David [Washington State Univ., Pullman, WA (United States); Zhao, Chuanlin [Washington State Univ., Pullman, WA (United States); Liu, Dong [Washington State Univ., Pullman, WA (United States); Yang, Tao [Washington State Univ., Pullman, WA (United States); Meng, Ming [Washington State Univ., Pullman, WA (United States); Zhang, Lin [Washington State Univ., Pullman, WA (United States); Ning, Jiawei [Washington State Univ., Pullman, WA (United States); Tashman, Zaid [Washington State Univ., Pullman, WA (United States)

    2015-01-31

    This project has led to the development of a real-time simulation platform for electric power grids called Grid Simulator or GridSim for simulating the dynamic and information network interactions of large- scale power systems. The platform consists of physical models of power system components including synchronous generators, loads and control, which are simulated using a modified commercial power simulator namely Transient Stability Analysis Tool (TSAT) [1] together with data cleanup components, as well as an emulated substation level and wide-area power analysis components. The platform also includes realistic representations of communication network middleware that can emulate the real-time information flow back and forth between substations and control centers in wide-area power systems. The platform has been validated on a realistic 6000-bus model of the western American power system. The simulator GridSim developed in this project is the first of its kind in its ability to simulate real-time response of large-scale power grids, and serves as a cost effective real-time stability and control simulation platform for power industry.

  3. Switch wear leveling

    Wu, Hunter; Sealy, Kylee; Gilchrist, Aaron

    2015-09-01

    An apparatus for switch wear leveling includes a switching module that controls switching for two or more pairs of switches in a switching power converter. The switching module controls switches based on a duty cycle control technique and closes and opens each switch in a switching sequence. The pairs of switches connect to a positive and negative terminal of a DC voltage source. For a first switching sequence a first switch of a pair of switches has a higher switching power loss than a second switch of the pair of switches. The apparatus includes a switch rotation module that changes the switching sequence of the two or more pairs of switches from the first switching sequence to a second switching sequence. The second switch of a pair of switches has a higher switching power loss than the first switch of the pair of switches during the second switching sequence.

  4. High power RF solid state power amplifier system

    Sims, III, William Herbert (Inventor); Chavers, Donald Gregory (Inventor); Richeson, James J. (Inventor)

    2011-01-01

    A high power, high frequency, solid state power amplifier system includes a plurality of input multiple port splitters for receiving a high-frequency input and for dividing the input into a plurality of outputs and a plurality of solid state amplifier units. Each amplifier unit includes a plurality of amplifiers, and each amplifier is individually connected to one of the outputs of multiport splitters and produces a corresponding amplified output. A plurality of multiport combiners combine the amplified outputs of the amplifiers of each of the amplifier units to a combined output. Automatic level control protection circuitry protects the amplifiers and maintains a substantial constant amplifier power output.

  5. Wind power generation and dispatch in competitive power markets

    Abreu, Lisias

    Wind energy is currently the fastest growing type of renewable energy. The main motivation is led by more strict emission constraints and higher fuel prices. In addition, recent developments in wind turbine technology and financial incentives have made wind energy technically and economically viable almost anywhere. In restructured power systems, reliable and economical operation of power systems are the two main objectives for the ISO. The ability to control the output of wind turbines is limited and the capacity of a wind farm changes according to wind speeds. Since this type of generation has no production costs, all production is taken by the system. Although, insufficient operational planning of power systems considering wind generation could result in higher system operation costs and off-peak transmission congestions. In addition, a GENCO can participate in short-term power markets in restructured power systems. The goal of a GENCO is to sell energy in such a way that would maximize its profitability. However, due to market price fluctuations and wind forecasting errors, it is essential for the wind GENCO to keep its financial risk at an acceptable level when constituting market bidding strategies. This dissertation discusses assumptions, functions, and methodologies that optimize short-term operations of power systems considering wind energy, and that optimize bidding strategies for wind producers in short-term markets. This dissertation also discusses uncertainties associated with electricity market environment and wind power forecasting that can expose market participants to a significant risk level when managing the tradeoff between profitability and risk.

  6. Harmonics in transmission power systems

    Wiechowski, Wojciech Tomasz

    in transmission power systems" was formulated. In this project, the entire 400 kV and 150 kV western transmission network of Energinet.dk is modelled using the simulation software DIgSILENT PowerFactory. A fundamental frequency load-flow model is used as a basis that is to be extended. The model is sought......, provided that background harmonic distortion, and the network configuration, are not changing during the measurement. It is shown that switching of a shunt linear power system component can result in variation of the harmonic levels that can be measured and used to verify the harmonic model of the network......, in order to determine which power system component, when switched, results in the largest change in harmonic levels, some initial harmonic simulations, using the created harmonic model of Energinet.dk transmission network, are performed. The criterion is that the measuring equipment shall not be installed...

  7. An Approach for Low Power CMOS Design

    Ravindra kumar chejara

    2015-03-01

    Full Text Available Power dissipation has emerged an important parameter in design of Low Power CMOS circuits. For this level converter and dual supply voltage assignments are used to reduce the power dissipation and propagation delay. In this paper, variable supply-voltage scheme (dual-VS scheme for dual power supplies along with voltage level converter is presented. Also paper presents an overall comparative analysis among various methods to achieve voltage level shifter even in lower technology comparative to higher ones and help user to select the best methods for same at this technology.

  8. Is power-space a continuum? Distance effect during power judgments.

    Jiang, Tianjiao; Zhu, Lei

    2015-12-01

    Despite the increasing evidence suggesting that power processing can activate vertical space schema, it still remains unclear whether this power-space is dichotomic or continuous. Here we tested the nature of the power-space by the distance effect, a continuous property of space cognition. In two experiments, participants were required to judge the power of one single word (Experiment 1) or compare the power of two words presented in pairs (Experiment 2). The power distance was indexed by the absolute difference of power ratings. Results demonstrated that reaction time decreased with the power distance, whereas accuracy increased with the power distance. The findings indicated that different levels of power were presented as different vertical heights, implying that there was a common mechanism underlying space and power cognition.

  9. Direct jet impingement cooling of power electronics

    Skuriat, Robert

    2012-01-01

    The aim of the work presented in this thesis is to improve the operational reliability of a power module and increase the efficiency of its associated cooling system by integrating the design of the cooler as part of the module. Power modules are increasingly used in a variety of applications ranging from aircraft and mass transport systems, to motor control and power conversion in the home. Reliability of the power module is very important in aerospace applications where the highest levels o...

  10. ULTRA HIGH POWER TRANSMISSION LINE TECHNIQUES

    The ultra-high power transmission line techniques including both failure mechanisms and component design are discussed. Failures resulting from...a waveguide. In view of the many advantages of the low loss mode in circular waveguide for ultra-high power levels, a mode transducer and a two...percent of the peak power of a standard rectangular wave guide. Water cooling is provided for high average power operation. Analysis of mode sup pression

  11. Electric power monthly, September 1990. [Glossary included

    1990-12-17

    The purpose of this report is to provide energy decision makers with accurate and timely information that may be used in forming various perspectives on electric issues. The power plants considered include coal, petroleum, natural gas, hydroelectric, and nuclear power plants. Data are presented for power generation, fuel consumption, fuel receipts and cost, sales of electricity, and unusual occurrences at power plants. Data are compared at the national, Census division, and state levels. 4 figs., 52 tabs. (CK)

  12. A power primer

    Jacob Cohen

    2007-09-01

    Full Text Available One possible reason for the continued neglect of statistical power analysis in research in the behavioral sciences is the inaccessibility of or difficulty with the standard material. A convenient, although not comprehensive, presentation of required sample sizes is provided. Effect-size indexes and conventional values for these are given for operationally defined small, medium, and large effects. The sample sizes necessary for .80 power to detect effects at these levels are tabled for 8 standard statistical tests: (1 the difference between independent means, (2 the significance of a product-moment correlation, (3 the difference between independent rs, (4 the sign test, (5 the difference between independent proportions, (6 chi-square tests for goodness of fit and contingency tables, (7 1-way analysis of variance (ANOVA, and (8 the significance of a multiple or multiple partial correlation.

  13. Hollow fiber optics with improved durability for high-peak-power pulses of Q-switched Nd:YAG lasers.

    Matsuura, Yuji; Tsuchiuchi, Akio; Noguchi, Hiroshi; Miyagi, Mitsunobu

    2007-03-10

    To improve the damage threshold of hollow optical waveguides for transmitting Q-switched Nd:YAG laser pulses, we optimize the metallization processes for the inner coating of fibers. For silver-coated hollow fiber as the base, second, and third Nd:YAG lasers, drying silver films at a moderate temperature and with inert gas flow is found to be effective. By using this drying process, the resistance to high-peak-power optical pulse radiation is drastically improved for fibers fabricated with and without the sensitizing process. The maximum peak power transmitted in the fiber is greater than 20 MW. To improve the energy threshold of aluminum-coated hollow fibers for the fourth and fifth harmonics of Nd:YAG lasers, a thin silver film is added between the aluminum film and the glass substrate to increase adhesion of the aluminum coating. By using this primer layer, the power threshold improves to 3 MW for the fourth harmonics of a Q-switched Nd:YAG laser light.

  14. Possible Power Estimation of Down-Regulated Offshore Wind Power Plants

    Gögmen, Tuhfe

    The penetration of offshore wind power is continuously increasing in the Northern European grids. To assure safety in the operation of the power system, wind power plants are required to provide ancillary services, including reserve power attained through down-regulating the wind farm from its...... power plant. The developed procedure, the PossPOW algorithm, can also be used in the wind farm control as it yields a real-time wind farm power curve. The modern wind turbines have a possible power signal at the turbine level and the current state of the art is to aggregate those signals to achieve...

  15. Demand, Energy, and Power Factor

    1994-08-01

    demand, but first, let’s talk some more about why electrical demand charges occur. Electric Load Leveling: 5 ** show flip chart of daily utility load (see...and cost savings for energy are available as a result of lowering demand. 3 ’~ show flip chart of block structure (see copy at end of script) Shown... flip chart (see copy at end of script) This is a graphical representation of real, apparent and reactive power in3 an AC circuit. Real power is the power

  16. Power-efficient computer architectures recent advances

    Själander, Magnus; Kaxiras, Stefanos

    2014-01-01

    As Moore's Law and Dennard scaling trends have slowed, the challenges of building high-performance computer architectures while maintaining acceptable power efficiency levels have heightened. Over the past ten years, architecture techniques for power efficiency have shifted from primarily focusing on module-level efficiencies, toward more holistic design styles based on parallelism and heterogeneity. This work highlights and synthesizes recent techniques and trends in power-efficient computer architecture.Table of Contents: Introduction / Voltage and Frequency Management / Heterogeneity and Sp

  17. Power theories for improved power quality

    Pasko, Marian

    2012-01-01

    Power quality describes a set of parameters of electric power and the load’s ability to function properly under specific conditions. It is estimated that problems relating to power quality costs the European industry hundreds of billions of Euros annually. In contrast, financing for the prevention of these problems amount to fragments of these costs. Power Theories for Improved Power Quality addresses this imbalance by presenting and assessing a range of methods and problems related to improving the quality of electric power supply. Focusing particularly on active compensators and the DSP based control algorithms, Power Theories for Improved Power Quality introduces the fundamental problems of electrical power. This introduction is followed by chapters which discuss: •‘Power theories’ including their historical development and application to practical problems, •operational principles of active compensator’s DSP control based algorithms using examples and results from laboratory research, and •t...

  18. On-chip power delivery and management

    Vaisband, Inna P; Popovich, Mikhail; Mezhiba, Andrey V; Köse, Selçuk; Friedman, Eby G

    2016-01-01

    This book describes methods for distributing power in high speed, high complexity integrated circuits with power levels exceeding many tens of watts and power supplies below a volt. It provides a broad and cohesive treatment of power delivery and management systems and related design problems, including both circuit network models and design techniques for on-chip decoupling capacitors, providing insight and intuition into the behavior and design of on-chip power distribution systems. Organized into subareas to provide a more intuitive flow to the reader, this fourth edition adds more than a hundred pages of new content, including inductance models for interdigitated structures, design strategies for multi-layer power grids, advanced methods for efficient power grid design and analysis, and methodologies for simultaneously placing on-chip multiple power supplies and decoupling capacitors. The emphasis of this additional material is on managing the complexity of on-chip power distribution networks.

  19. Energy storage in future power systems

    Rasmussen, Claus Nygaard; Østergaard, Jacob; Divya, K. C.

    2011-01-01

    Most sources of renewable power are characterised by uncontrollable and chaotic variations in power output. We here look at how energy storage may benefit renewable power generation by making it available in periods with little or no intermittent generation and thereby prevent additional...... conventional generation form being used. In addition to this, one of the strongest concerns in relation to renewable power is the instability in the electric power system that it may introduce as a result of large and relatively fast power fluctuations. An additional benefit of energy storage is therefore its...... of renewable energy. Meanwhile, the insurance of power system stability through reduction of power gradients is of major importance even at lower penetration levels and some form of energy storage therefore seems unavoidable. A variety of technologies are available for storage of energy in the power system...

  20. Women, Power, and Libraries.

    Schuman, Patricia Glass

    1984-01-01

    Discusses the concept of power in the context of women and the library profession, citing views of power by Max Weber, John Kenneth Galbraith, Letty Cottin Pogrebin, and Rosabeth Moss Kantor. Male power and female submission, defining power, organizing for power, and sharing power are highlighted. A 12-item bibliography is included. (EJS)