WorldWideScience

Sample records for batio3to electrical loading

  1. Spatial electric load forecasting

    CERN Document Server

    Willis, H Lee

    2002-01-01

    Spatial Electric Load Forecasting Consumer Demand for Power and ReliabilityCoincidence and Load BehaviorLoad Curve and End-Use ModelingWeather and Electric LoadWeather Design Criteria and Forecast NormalizationSpatial Load Growth BehaviorSpatial Forecast Accuracy and Error MeasuresTrending MethodsSimulation Method: Basic ConceptsA Detailed Look at the Simulation MethodBasics of Computerized SimulationAnalytical Building Blocks for Spatial SimulationAdvanced Elements of Computerized SimulationHybrid Trending-Simulation MethodsAdvanced

  2. Electrical load detection aparatus

    DEFF Research Database (Denmark)

    2010-01-01

    A load detection technique for a load comprising multiple frequency-dependant sub-loads comprises measuring a representation of the impedance characteristic of the load; providing stored representations of a multiplicity of impedance characteristics of the load; each one of the stored representat...

  3. Electrical load modeling

    Energy Technology Data Exchange (ETDEWEB)

    Valgas, Helio Moreira; Pinto, Roberto del Giudice R.; Franca, Carlos [Companhia Energetica de Minas Gerais (CEMIG), Belo Horizonte, MG (Brazil); Lambert-Torres, Germano; Silva, Alexandre P. Alves da; Pires, Robson Celso; Costa Junior, Roberto Affonso [Escola Federal de Engenharia de Itajuba, MG (Brazil)

    1994-12-31

    Accurate dynamic load models allow more precise calculations of power system controls and stability limits, which are critical mainly in the operation planning of power systems. This paper describes the development of a computer program (software) for static and dynamic load model studies using the measurement approach for the CEMIG system. Two dynamic load model structures are developed and tested. A procedure for applying a set of measured data from an on-line transient recording system to develop load models is described. (author) 6 refs., 17 figs.

  4. electrical load survey electrical load survey and forecast for a ...

    African Journals Online (AJOL)

    eobe

    1, 2NATIONAL CENTRE FOR HYDROPOWER RESEARCH AND DEV., UNIV. OF ILORIN ... be integrated to meet the present and future energy needs of this are ... paper reports the results of electrical load demand and forecast for Elebu rural community located in Kwara State, ... geothermal and ocean energies [5].

  5. Relating Electronic and Geometric Structure of Atomic Layer Deposited BaTiO3 to its Electrical Properties.

    Science.gov (United States)

    Torgersen, Jan; Acharya, Shinjita; Dadlani, Anup Lal; Petousis, Ioannis; Kim, Yongmin; Trejo, Orlando; Nordlund, Dennis; Prinz, Fritz B

    2016-04-21

    Atomic layer deposition allows the fabrication of BaTiO3 (BTO) ultrathin films with tunable dielectric properties, which is a promising material for electronic and optical technology. Industrial applicability necessitates a better understanding of their atomic structure and corresponding properties. Through the use of element-specific X-ray absorption near edge structure (XANES) analysis, O K-edge of BTO as a function of cation composition and underlying substrate (RuO2 and SiO2) is revealed. By employing density functional theory and multiple scattering simulations, we analyze the distortions in BTO's bonding environment captured by the XANES spectra. The spectral weight shifts to lower energy with increasing Ti content and provides an atomic scale (microscopic) explanation for the increase in leakage current density. Differences in film morphologies in the first few layers near substrate-film interfaces reveal BTO's homogeneous growth on RuO2 and its distorted growth on SiO2. This work links structural changes to BTO thin-film properties and provides insight necessary for optimizing future BTO and other ternary metal oxide-based thin-film devices.

  6. Electric load management and energy conservation

    Science.gov (United States)

    Kheir, N. A.

    1976-01-01

    Electric load management and energy conservation relate heavily to the major problems facing power industry at present. The three basic modes of energy conservation are identified as demand reduction, increased efficiency and substitution for scarce fuels. Direct and indirect load management objectives are to reduce peak loads and have future growth in electricity requirements in such a manner to cause more of it to fall off the system's peak. In this paper, an overview of proposed and implemented load management options is presented. Research opportunities exist for the evaluation of socio-economic impacts of energy conservation and load management schemes specially on the electric power industry itself.

  7. Load research and load estimation in electricity distribution

    Energy Technology Data Exchange (ETDEWEB)

    Seppaelae, A. [VTT Energy, Espoo (Finland). Energy Systems

    1996-12-31

    The topics introduced in this thesis are: the Finnish load research project, a simple form customer class load model, analysis of the origins of customers load distribution, a method for the estimation of the confidence interval of customer loads and Distribution Load Estimation (DLE) which utilises both the load models and measurements from distribution networks. The Finnish load research project started in 1983. The project was initially coordinated by the Association of Finnish Electric Utilities and 40 utilities joined the project. Now there are over 1000 customer hourly load recordings in a database. A simple form customer class load model is introduced. The model is designed to be practical for most utility applications and has been used by the Finnish utilities for several years. The only variable of the model is the customers annual energy consumption. The model gives the customers average hourly load and standard deviation for a selected month, day and hour. The statistical distribution of customer loads is studied and a model for customer electric load variation is developed. The model results in a lognormal distribution as an extreme case. Using the `simple form load model`, a method for estimating confidence intervals (confidence limits) of customer hourly load is developed. The two methods selected for final analysis are based on normal and lognormal distribution estimated in a simplified manner. The estimation of several cumulated customer class loads is also analysed. Customer class load estimation which combines the information from load models and distribution network load measurements is developed. This method, called Distribution Load Estimation (DLE), utilises information already available in the utilities databases and is thus easy to apply

  8. Electricity load modelling using computational intelligence

    NARCIS (Netherlands)

    Ter Borg, R.W.

    2005-01-01

    As a consequence of the liberalisation of the electricity markets in Europe, market players have to continuously adapt their future supply to match their customers' demands. This poses the challenge of obtaining a predictive model that accurately describes electricity loads, current in this thesis.

  9. Electricity Crisis and Load Management in Bangladesh

    Directory of Open Access Journals (Sweden)

    Rajib Kanti Das

    2012-09-01

    Full Text Available Bangladesh is a densely populated country. Only a small part of her area is electrified which cover around 18% of total population. The people who are in the electrified area are suffering from severe load shedding. A systematic load management procedure related to demand side may improve the situation is the research problem. The major objectives serve by the research are to analyze contemporary electricity status with a view to drawing inference about demand supply gap and extracting benefits from load management. Data supplied by the Bangladesh Power Development Board, World Bank and outcome of survey are analyzed with some simple statistical tools to test the hypothesis. Analysis discloses that with properly managed uses of electricity with load switch and rotation week-end can improve the concurrent condition of electricity. Moreover, introducing smart distribution system, reducing system loss, shifting load to off-peak, large scale use of prepaid mete, observing energy week and using energy efficient home and office appliance are recommended to improve load through demand side management. Some other recommendations such as introducing alternative energy, public private partnership and using renewable energy development and producing energy locally are made for load management from the supply side.

  10. ELECTRICAL LOAD ANTICIPATOR AND RECORDER

    Science.gov (United States)

    Werme, J.E.

    1961-09-01

    A system is described in which an indication of the prevailing energy consumption in an electrical power metering system and a projected power demand for one demand in terval is provided at selected increments of time within the demand interval. Each watt-hour meter in the system is provided with an impulse generator that generates two impulses for each revolution of the meter disc. In each demand interval, for example, one half-hour, of the metering system, the total impulses received from all of the meters are continuously totaled for each 5-minute interval and multiplied by a number from 6 to 1 depending upon which 5- minute interval the impulses were received. This value is added to the total pulses received in the intervals preceding the current 5-minute interval within the half-hour demand interval tc thereby provide an indication of the projected power demand every 5 minutes in the demand interval.

  11. 30 CFR 56.6602 - Static electricity dissipation during loading.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Static electricity dissipation during loading... Explosives Extraneous Electricity § 56.6602 Static electricity dissipation during loading. When explosive material is loaded pneumatically into a blasthole in a manner that generates a static electricity hazard...

  12. Extracting Operating Modes from Building Electrical Load Data: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Frank, S.; Polese, L. G.; Rader, E.; Sheppy, M.; Smith, J.

    2012-01-01

    Empirical techniques for characterizing electrical energy use now play a key role in reducing electricity consumption, particularly miscellaneous electrical loads, in buildings. Identifying device operating modes (mode extraction) creates a better understanding of both device and system behaviors. Using clustering to extract operating modes from electrical load data can provide valuable insights into device behavior and identify opportunities for energy savings. We present a fast and effective heuristic clustering method to identify and extract operating modes in electrical load data.

  13. Method and system employing graphical electric load categorization to identify one of a plurality of different electric load types

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Yi; Du, Liang

    2016-09-13

    A system for different electric loads includes sensors structured to sense voltage and current signals for each of the different electric loads; a hierarchical load feature database having a plurality of layers, with one of the layers including a plurality of different load categories; and a processor. The processor acquires voltage and current waveforms from the sensors for a corresponding one of the different electric loads; maps a voltage-current trajectory to a grid including a plurality of cells, each of which is assigned a binary value of zero or one; extracts a plurality of different features from the mapped grid of cells as a graphical signature of the corresponding one of the different electric loads; derives a category of the corresponding one of the different electric loads from the database; and identifies one of a plurality of different electric load types for the corresponding one of the different electric loads.

  14. Peak Electric Load Relief in Northern Manhattan

    Directory of Open Access Journals (Sweden)

    Hildegaard D. Link

    2014-08-01

    Full Text Available The aphorism “Think globally, act locally,” attributed to René Dubos, reflects the vision that the solution to global environmental problems must begin with efforts within our communities. PlaNYC 2030, the New York City sustainability plan, is the starting point for this study. Results include (a a case study based on the City College of New York (CCNY energy audit, in which we model the impacts of green roofs on campus energy demand and (b a case study of energy use at the neighborhood scale. We find that reducing the urban heat island effect can reduce building cooling requirements, peak electricity loads stress on the local electricity grid and improve urban livability.

  15. 30 CFR 57.6602 - Static electricity dissipation during loading.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Static electricity dissipation during loading... MINES Explosives Extraneous Electricity-Surface and Underground § 57.6602 Static electricity dissipation... generates a static electricity hazard— (a) An evaluation of the potential static electricity hazard shall be...

  16. Experimenting with Electrical Load Sensing on a Backhoe Loader

    DEFF Research Database (Denmark)

    Andersen, Torben Ole; Hansen, Michael Rygaard; Pedersen, Henrik Clemmensen

    2005-01-01

    Where traditional load sensing is made using hydro-mechanical regulators and load pressure is fed back hydraulically, electrical load sensing employs the usage of electronic sensors and electrically actuated components. This brings forth new possibilities, but also imposes problems concerning...

  17. Assessing and Reducing Miscellaneous Electric Loads (MELs) in Lodging

    Energy Technology Data Exchange (ETDEWEB)

    Rauch, Emily M.

    2011-09-01

    Miscellaneous electric loads (MELs) are the loads outside of a building's core functions of heating, ventilating, air conditioning, lighting, and water heating. This report reviews methods to reduce MELs in lodging.

  18. System and method employing a self-organizing map load feature database to identify electric load types of different electric loads

    Science.gov (United States)

    Lu, Bin; Harley, Ronald G.; Du, Liang; Yang, Yi; Sharma, Santosh K.; Zambare, Prachi; Madane, Mayura A.

    2014-06-17

    A method identifies electric load types of a plurality of different electric loads. The method includes providing a self-organizing map load feature database of a plurality of different electric load types and a plurality of neurons, each of the load types corresponding to a number of the neurons; employing a weight vector for each of the neurons; sensing a voltage signal and a current signal for each of the loads; determining a load feature vector including at least four different load features from the sensed voltage signal and the sensed current signal for a corresponding one of the loads; and identifying by a processor one of the load types by relating the load feature vector to the neurons of the database by identifying the weight vector of one of the neurons corresponding to the one of the load types that is a minimal distance to the load feature vector.

  19. Electrical Load and Energy Management. Course Outline and Instructional Materials.

    Science.gov (United States)

    Wang, Paul

    Presented are 13 lecture outlines with accompanying handouts and reference lists for teaching school administrators and maintenance personnel the use of electrical load management as an energy conservation tool. To aid course participants in making cost effective use of electrical power, methods of load management in a variety of situations are…

  20. 101 Modelling and Forecasting Periodic Electric Load for a ...

    African Journals Online (AJOL)

    User

    2012-01-24

    Jan 24, 2012 ... In this work, three models are used to analyze the electric load capacity of a ..... Forecasting electricity prices for a day-ahead pool-based electric energy market. ... Control, Operation and Management, Hong Kong pgs.782–7.

  1. Predicting the Response of Electricity Load to Climate Change

    Energy Technology Data Exchange (ETDEWEB)

    Sullivan, Patrick [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Colman, Jesse [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Kalendra, Eric [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2015-07-28

    Our purpose is to develop a methodology to quantify the impact of climate change on electric loads in the United States. We perform simple linear regression, assisted by geospatial smoothing, on paired temperature and load time-series to estimate the heating- and coolinginduced sensitivity to temperature across 300 transmission zones and 16 seasonal and diurnal time periods. The estimated load sensitivities can be coupled with climate scenarios to quantify the potential impact of climate change on load, with a primary application being long-term electricity scenarios. The method allows regional and seasonal differences in climate and load response to be reflected in the electricity scenarios. While the immediate product of this analysis was designed to mesh with the spatial and temporal resolution of a specific electricity model to enable climate change scenarios and analysis with that model, we also propose that the process could be applied for other models and purposes.

  2. Methods for Analyzing Electric Load Shape and its Variability

    Energy Technology Data Exchange (ETDEWEB)

    Price, Philip

    2010-05-12

    Current methods of summarizing and analyzing electric load shape are discussed briefly and compared. Simple rules of thumb for graphical display of load shapes are suggested. We propose a set of parameters that quantitatively describe the load shape in many buildings. Using the example of a linear regression model to predict load shape from time and temperature, we show how quantities such as the load?s sensitivity to outdoor temperature, and the effectiveness of demand response (DR), can be quantified. Examples are presented using real building data.

  3. Mining Rules from Electrical Load Time Series Data Set

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The mining of the rules from the electrical load time series data which are collected from the EMS (Energy Management System) is discussed. The data from the EMS are too huge and sophisticated to be understood and used by the power system engineer, while useful information is hidden in the electrical load data. The authors discuss the use of fuzzy linguistic summary as data mining method to induce the rules from the electrical load time series. The data preprocessing techniques are also discussed in the paper.

  4. Peak load pricing in the electric utility industry

    Energy Technology Data Exchange (ETDEWEB)

    Wenders, J.T.

    In the electric utility industry, cost minimization requires that heterogeneous electric generation technologies be used to produce electricity demands of different durations. In contrast to the conclusions of traditional peak-load pricing theory, the existence of a heterogeneous capital stock means that off-peak marginal cost prices almost always should include some marginal capacity costs, and that the profit maximizing regulated electric utility may set peak price above marginal cost and off-peak price below marginal cost in order to encourage the expansion of capital-intensive base load generating capacity. (auth)

  5. A Top-Down Spatially Resolved Electrical Load Model

    Directory of Open Access Journals (Sweden)

    Martin Robinius

    2017-03-01

    Full Text Available The increasing deployment of variable renewable energy sources (VRES is changing the source regime in the electrical energy sector. However, VRES feed-in from wind turbines and photovoltaic systems is dependent on the weather and only partially predictable. As a result, existing energy sector models must be re-evaluated and adjusted as necessary. In long-term forecast models, the expansion of VRES must be taken into account so that future local overloads can be identified and measures taken. This paper focuses on one input factor for electrical energy models: the electrical load. We compare two different types to describe this, namely vertical grid load and total load. For the total load, an approach for a spatially-resolved electrical load model is developed and applied at the municipal level in Germany. This model provides detailed information about the load at a quarterly-hour resolution across 11,268 German municipalities. In municipalities with concentrations of energy-intensive industry, high loads are expected, which our simulation reproduces with a good degree of accuracy. Our results also show that municipalities with energy-intensive industry have a higher simulated electric load than neighboring municipalities that do not host energy-intensive industries. The underlying data was extracted from publically accessible sources and therefore the methodology introduced is also applicable to other countries.

  6. Energy efficiency indicators for high electric-load buildings

    Energy Technology Data Exchange (ETDEWEB)

    Aebischer, Bernard; Balmer, Markus A.; Kinney, Satkartar; Le Strat, Pascale; Shibata, Yoshiaki; Varone, Frederic

    2003-06-01

    Energy per unit of floor area is not an adequate indicator for energy efficiency in high electric-load buildings. For two activities, restaurants and computer centres, alternative indicators for energy efficiency are discussed.

  7. A Statistical Survey of the UK Residential Sector Electrical Loads

    Science.gov (United States)

    Tsagarakis, George; Collin, Adam; Kiprakis, Aristides

    2013-09-01

    This article presents a comprehensive statistical analysis of data obtained from a wide range of literature on the most widely used appliances in the UK residential load sector, as well as a comprehensive technology and market survey conducted by the authors. The article focuses on the individual appliances and begins by consideration of the electrical operations performed by the load. This approach allows for the loads to be categorised based on the electrical characteristics, which is particularly important for implementing load-use statistics in power system analysis. In addition to this, device ownership statistics and probability density functions of power demand are presented for the main residential loads. Although the data presented is primarily intended as a resource for the development of load profiles for power system analysis, it contains a large volume of information that provides a useful database for the wider research community.

  8. Impacts of Climate Change on Electric Transmission Capacity and Peak Electricity Load in the United States

    Science.gov (United States)

    Chester, M.; Bartos, M. D.; Eisenberg, D. A.; Gorman, B.; Johnson, N.

    2015-12-01

    Climate change may hinder future electricity reliability by reducing electric transmission capacity while simultaneously increasing electricity demand. This study estimates potential climate impacts to electric transmission capacity and peak electricity load in the United States. Electric power cables suffer decreased transmission capacity as they get hotter; similarly, during the summer peak period, electricity demand typically increases with hotter ambient air temperatures due to increased cooling loads. As atmospheric carbon concentrations increase, higher air temperatures may strain power infrastructure by reducing transmission capacity and increasing peak electricity loads. Taken together, these coincident impacts may have unpredictable consequences for electric power reliability. We estimate the effects of climate change on both the rated capacity of transmission infrastructure and expected electricity demand for 120 electrical utilities across the United States. We estimate climate-attributable capacity reductions to transmission lines by constructing thermal models of representative conductors, then forcing these models with downscaled CMIP5 temperature projections to determine the relative change in rated ampacity over the twenty-first century. Next, we assess the impact of climate change on electricity demand by using historical relationships between ambient temperature and utility-scale summertime peak load to estimate the extent to which climate change will incur additional peak load increases. We use downscaled temperature projections from 11 CMIP5 GCM models under 3 atmospheric carbon scenarios. We find that by mid-century (2040-2060), climate change may reduce average summertime transmission capacity by 4-6% relative to the 1990-2010 reference period. At the same time, peak summertime loads may rise by roughly 2-12% on average due to increases in daily maximum air temperature. In the absence of energy efficiency gains, demand-side management programs

  9. Reallocating Charging Loads of Electric Vehicles in Distribution Networks

    Directory of Open Access Journals (Sweden)

    Mohammed Jasim M. Al Essa

    2016-02-01

    Full Text Available In this paper, the charging loads of electric vehicles were controlled to avoid their impact on distribution networks. A centralized control algorithm was developed using unbalanced optimal power flow calculations with a time resolution of one minute. The charging loads were optimally reallocated using a central controller based on non-linear programming. Electric vehicles were recharged using the proposed control algorithm considering the network constraints of voltage magnitudes, voltage unbalances, and limitations of the network components (transformers and cables. Simulation results showed that network components at the medium voltage level can tolerate high uptakes of uncontrolled recharged electric vehicles. However, at the low voltage level, network components exceeded their limits with these high uptakes of uncontrolled charging loads. Using the proposed centralized control algorithm, these high uptakes of electric vehicles were accommodated in the network under study without the need of upgrading the network components.

  10. Effects of using passive filter for reduce electrical load harmonics

    Science.gov (United States)

    Sucita, T.

    2016-04-01

    Due to the use of electrical current load that uses a lot of electronic components (passive non-linear electrical loads), so the impact will cause harmonics in the electrical network system. These harmonics can unwittingly cause a relatively large loss in electrical energy consumption and can lower the power factor of an electrical installation. Limits how much the harmonic distortion that is installed on the load adjusted to the IEEE 519-1992 standard. The study was conducted by taking data on a network of electrical installation of a building using measuring devices Fluke 43B Power Quality Analyser. The data is then processed and consulted with the standard IEEE 519-1992. Once the data has a discrepancy with the standard, further made the filter design using linear passive components. The design is then installed on the network installation by means of simulated order harmonic losses can be overcome so that the circuit meets the IEEE standard installation by changing the parameters of the linear load L and C. The results of this study indicate that THDi value decreased after the installation of filters for phase R fell by 9.39%, the S phase decreased by 7.54% and for the T phase decreased by 16.88%. So that meets the IEEE standard by 15%.

  11. Load management through agent based coordination of flexible electricity consumers

    DEFF Research Database (Denmark)

    Clausen, Anders; Jørgensen, Bo Nørregaard

    2015-01-01

    Demand Response (DR) offers a cost-effective and carbonfriendly way of performing load balancing. DR describes a change in the electricity consumption of flexible consumers in response to the supply situation. In DR, flexible consumers may perform their own load balancing through load management....... In this paper, we propose an approach to perform such coordination through a Virtual Power Plant (VPP)[1]. We represent flexible electricity consumers as software agents and we solve the coordination problem through multi-objective multi-issue optimization using a mediator-based negotiation mechanism. We...... illustrate how we can coordinate flexible consumers through a VPP in response to external events simulating the need for load balancing services....

  12. Loading models for electric vehicles; Lademodelle fuer Elektrofahrzeuge

    Energy Technology Data Exchange (ETDEWEB)

    Mezger, Tomas [Forschungsstelle fuer Energiewirtschaft e.V., Muenchen (Germany)

    2011-07-01

    About 5 to 7 million electric vehicles have adverse effects on the electricity grid. Thus, there is a need to develop optimized loading concepts, which generate an added value both for the energy industry as well as for the vehicle owners. A two-stage analysis method is used for this. Within the first step it is examined, how defined fleet of electric vehicles can be loaded optimally with electricity taking into account the specific vehicle usage. In the second step, the charging models are again evaluated from a user perspective. The impact of the driving behavior and charge characteristics on the aging of the battery are considered specifically. Charging possibilities are identified in order to increase the battery life.

  13. Evaluation of solar thermal storage for base load electricity generation

    Science.gov (United States)

    Adinberg, R.

    2012-10-01

    In order to stabilize solar electric power production during the day and prolong the daily operating cycle for several hours in the nighttime, solar thermal power plants have the options of using either or both solar thermal storage and fossil fuel hybridization. The share of solar energy in the annual electricity production capacity of hybrid solar-fossil power plants without energy storage is only about 20%. As it follows from the computer simulations performed for base load electricity demand, a solar annual capacity as high as 70% can be attained by use of a reasonably large thermal storage capacity of 22 full load operating hours. In this study, the overall power system performance is analyzed with emphasis on energy storage characteristics promoting a high level of sustainability for solar termal electricity production. The basic system parameters, including thermal storage capacity, solar collector size, and annual average daily discharge time, are presented and discussed.

  14. Characterization of electric load with Information Theory quantifiers

    Science.gov (United States)

    Aquino, Andre L. L.; Ramos, Heitor S.; Frery, Alejandro C.; Viana, Leonardo P.; Cavalcante, Tamer S. G.; Rosso, Osvaldo A.

    2017-01-01

    This paper presents a study of the electric load behavior based on the Causality Complexity-Entropy Plane. We use a public data set, namely REDD, which contains detailed power usage information from several domestic appliances. In our characterization, we use the available power data of the circuit/devices of all houses. The Bandt-Pompe methodology combined with the Causality Complexity-Entropy Plane was used to identify and characterize regimes and behaviors over these data. The results showed that this characterization provides a useful insight into the underlying dynamics that govern the electric load.

  15. Adaptive load forecasting of the Hellenic electric grid

    Institute of Scientific and Technical Information of China (English)

    S. Sp. PAPPAS; L. EKONOMOU; V. C. MOUSSAS; P. KARAMPELAS; S. K. KATSIKAS

    2008-01-01

    Designers are required to plan for future expansion and also to estimate the grid's future utilization. This means that an effective modeling and forecasting technique,which will use efficiently the information contained in the available data,is required,so that important data properties can be extracted and projected into the future. This study proposes an adaptive method based on the multi-model partitioning algorithm (MMPA),for short-term electricity load forecasting using real data. The grid's utilization is initially modeled using a multiplicative seasonal ARIMA (autoregressive integrated moving average) model. The proposed method uses past data to learn and model the normal periodic behavior of the electric grid. Either ARMA (autoregressive moving average) or state-space models can be used for the load pattern modeling. Load anomalies such as unexpected peaks that may appear during the summer or unexpected faults (blackouts) are also modeled. If the load pattern does not match the normal be-havior of the load,an anomaly is detected and,furthermore,when the pattern matches a known case of anomaly,the type of anomaly is identified. Real data were used and real cases were tested based on the measurement loads of the Hellenic Public Power Cooperation S.A.,Athens,Greece. The applied adaptive multi-model filtering algorithm identifies successfully both normal periodic behavior and any unusual activity of the electric grid. The performance of the proposed method is also compared to that produced by the ARIMA model.

  16. 77 FR 70484 - Preoperational Testing of Onsite Electric Power Systems To Verify Proper Load Group Assignments...

    Science.gov (United States)

    2012-11-26

    ... COMMISSION Preoperational Testing of Onsite Electric Power Systems To Verify Proper Load Group Assignments... Power Systems to Verify Proper Load Group Assignments, Electrical Separation, and Redundancy.'' DG-1294... encompass preoperational testing of electrical power systems used to meet current Station...

  17. Electrical load management for the California water system

    Energy Technology Data Exchange (ETDEWEB)

    Krieg, B.; Lasater, I.; Blumstein, C.

    1977-07-01

    To meet its water needs California has developed an extensive system for transporting water from areas with high water runoff to areas with high water demand. This system annually consumes more than 6 billion kilowatt hours (kWh) of electricity for pumping water and produces more than 12 billion kWh/year of hydroelectric power. From the point of view of energy conservation, the optimum operation of the California water supply system would require that pumping be done at night and generation be done during the day. Night pumping would reduce electric power peak load demand and permit the pumps to be supplied with electricity from ''base load'' generating plants. Daytime hydro power generation would augment peak load power generation by fossil-fuel power plants and save fuel. The technical and institutional aspects of this type of electric power load management for water projects are examined for the purpose of explaining some of the actions which might be pursued and to develop recommendations for the California Energy Resources Conservation and Development Commission (ERCDC). The California water supply system is described. A brief description is given of various energy conservation methods, other than load management, that can be used in the management of water resources. An analysis of load management is presented. Three actions for the ERCDC are recommended: the Commission should monitor upcoming power contract negotiations between the utilities and the water projects; it should determine the applicability of the power-pooling provisions of the proposed National Energy Act to water systems; and it should encourage and support detailed studies of load management methods for specific water projects.

  18. Temperature and seasonality influences on Spanish electricity load

    Energy Technology Data Exchange (ETDEWEB)

    Pardo, Angel; Meneu, Vicente [Departamento de Economia Financiera y Matematica, Facultad de Economia, Avda. de los Naranjos s/n., Edificio Departamental Oriental, Universidad de Valencia, 46022 Valencia (Spain); Valor, Enric [Departamento de Termodinamica, Universidad de Valencia, 46100 Burjassot, Valencia (Spain)

    2002-01-01

    Deregulation of the Spanish electricity market in 1998 and the possible listing of electricity or weather derivative contracts have encouraged the study of the relationship between electricity demand and weather in Spain. In this paper, a transfer function intervention model is developed for forecasting daily electricity load from cooling and heating degree-days. The influence of weather and seasonality is proved, and is significant even when the autoregressive effects and the dynamic specification of the temperature are taken into account. The estimated general model shows a high predictive power. The results and information presented in this paper could be of interest for current users and potential traders in the deregulated Spanish electricity market.

  19. Power quality load management for large spacecraft electrical power systems

    Science.gov (United States)

    Lollar, Louis F.

    1988-01-01

    In December, 1986, a Center Director's Discretionary Fund (CDDF) proposal was granted to study power system control techniques in large space electrical power systems. Presented are the accomplishments in the area of power system control by power quality load management. In addition, information concerning the distortion problems in a 20 kHz ac power system is presented.

  20. Load As A Reliability Resource in the Restructured Electricity Market

    Energy Technology Data Exchange (ETDEWEB)

    Kueck, J.D.

    2002-06-10

    Recent electricity price spikes are painful reminders of the value that meaningful demand-side responses could bring to the restructuring US electricity system. Review of the aggregate offers made by suppliers confirms that even a modest increase in demand elasticity could dramatically reduce these extremes in price volatility. There is a strong need for dramatically increased customer participation in these markets to enhance system reliability and reduce price volatility. Indeed, allowing customers to manage their loads in response to system conditions might be thought of as the ultimate reliability resource. Most would agree that meaningful demand-side responses to price are the hallmark of a well-functioning competitive market [1]. Yet, in today's markets for electricity, little or no such response is evident. The reason is simple: customers currently do not experience directly the time-varying costs of their consumption decisions. Consequently, they have no incentive to modify these decisions in ways that might enhance system reliability or improve the efficiency of the markets in which electricity is traded. Increased customer participation is a necessary step in the evolution toward more efficient markets for electricity and ancillary services. This scoping report provides a three-part assessment of the current status of efforts to enhance the ability of customer's load to participate in competitive markets with a specific focus on the role of customer loads in enhancing electricity system reliability. First, this report considers the definitions of electricity-reliability-enhancing ancillary services (Section 2) and a preliminary assessment of the ability of customer's loads to provide these services. Second, is a review a variety of programs in which load has been called on as a system reliability resource (Section 3). These experiences, drawn from both past and current utility and ISO programs, focus on programs triggered by system

  1. Assessing and Reducing Miscellaneous Electric Loads (MELs) in Banks

    Energy Technology Data Exchange (ETDEWEB)

    Rauch, Emily M.

    2012-09-01

    Miscellaneous electric loads (MELs) are loads outside of a building's core functions of heating, ventilating, air conditioning, lighting, and water heating. MELs are a large percentage of total building energy loads. This report reviews methods for reducing MELs in Banks. Reducing MELs in a bank setting requires both local and corporate action. Corporate action centers on activities to prioritize and allocate the right resources to correct procurement and central control issues. Local action includes branch assessment or audits to identify specific loads and needs. The worksheet at the end of this guide can help with cataloging needed information and estimating savings potential. The following steps provide a guide to MEL reductions in Bank Branches. The general process has been adapted from a process developed for office buildings the National Renewable Energy Laboratory (NREL, 2011).

  2. Broad electrical tuning of graphene-loaded plasmonic antennas.

    Science.gov (United States)

    Yao, Yu; Kats, Mikhail A; Genevet, Patrice; Yu, Nanfang; Song, Yi; Kong, Jing; Capasso, Federico

    2013-03-13

    Plasmonic antennas enable the conversion of light from free space into subwavelength volumes and vice versa, which facilitates the manipulation of light at the nanoscale. Dynamic control of the properties of antennas is desirable for many applications, including biochemical sensors, reconfigurable meta-surfaces and compact optoelectronic devices. The combination of metallic structures and graphene, which has gate-voltage dependent optical properties, is emerging as a possible platform for electrically controlled plasmonic devices. In this paper, we demonstrate in situ control of antennas using graphene as an electrically tunable load in the nanoscale antenna gap. In our experiments, we demonstrate electrical tuning of graphene-loaded antennas over a broad wavelength range of 650 nm (∼140 cm(-1), ∼10% of the resonance frequency) in the mid-infrared (MIR) region. We propose an equivalent circuit model to quantitatively analyze the tuning behavior of graphene-loaded antenna pairs and derive an analytical expression for the tuning range of resonant wavelength. In a separate experiment, we used doubly resonant antenna arrays to achieve MIR optical intensity modulation with maximum modulation depth of more than 30% and bandwidth of 600 nm (∼100 cm(-1), 8% of the resonance frequency). This study shows that combining graphene with metallic nanostructures provides a route to electrically tunable optical and optoelectronic devices.

  3. Load Forecasting in Electric Utility Integrated Resource Planning

    Energy Technology Data Exchange (ETDEWEB)

    Carvallo, Juan Pablo [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Larsen, Peter H. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Sanstad, Alan H [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Goldman, Charles A. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2017-07-19

    Integrated resource planning (IRP) is a process used by many vertically-integrated U.S. electric utilities to determine least-cost/risk supply and demand-side resources that meet government policy objectives and future obligations to customers and, in many cases, shareholders. Forecasts of energy and peak demand are a critical component of the IRP process. There have been few, if any, quantitative studies of IRP long-run (planning horizons of two decades) load forecast performance and its relationship to resource planning and actual procurement decisions. In this paper, we evaluate load forecasting methods, assumptions, and outcomes for 12 Western U.S. utilities by examining and comparing plans filed in the early 2000s against recent plans, up to year 2014. We find a convergence in the methods and data sources used. We also find that forecasts in more recent IRPs generally took account of new information, but that there continued to be a systematic over-estimation of load growth rates during the period studied. We compare planned and procured resource expansion against customer load and year-to-year load growth rates, but do not find a direct relationship. Load sensitivities performed in resource plans do not appear to be related to later procurement strategies even in the presence of large forecast errors. These findings suggest that resource procurement decisions may be driven by other factors than customer load growth. Our results have important implications for the integrated resource planning process, namely that load forecast accuracy may not be as important for resource procurement as is generally believed, that load forecast sensitivities could be used to improve the procurement process, and that management of load uncertainty should be prioritized over more complex forecasting techniques.

  4. Electric Loading Simulation System for Missile Wings and Rudders

    Institute of Scientific and Technical Information of China (English)

    QI Rong; LIN Hui; CHEN Ming

    2006-01-01

    The design and the realization of missile wings and rudders loading simulation system based on digital signal processor (DSP) TMS320LF2407 and direct torque control (DTC) servo driver ACS600 are discussed. The structure and opration principle for the system are presented. Speediness and elimination of superabundant torque are two key difficulties for electric loading simulation system. The method which can eliminate the superabundant torque is researched. Test results show the airflow resistance when missile wings and rudders are spreading can be rapidly simulated with high accuracy.

  5. Short Term Electrical Load Forecasting by Artificial Neural Network

    Directory of Open Access Journals (Sweden)

    Hong Li

    2016-07-01

    Full Text Available This paper presents an application of artificial neural networks for short-term times series electrical load forecasting. An adaptive learning algorithm is derived from system stability to ensure the convergence of training process. Historical data of hourly power load as well as hourly wind power generation are sourced from European Open Power System Platform. The simulation demonstrates that errors steadily decrease in training with the adaptive learning factor starting at different initial value and errors behave volatile with constant learning factors with different values

  6. Usage of Lightning Arrester Line to Feed Light Electrical Loads

    Directory of Open Access Journals (Sweden)

    Hani B. Odeh

    2009-01-01

    Full Text Available In remote areas, light loads (tens of kilowatts are scattered and situated in the field of high voltage lines (66KV and above. These loads are very far from the main feeders/sub-stations (33KV-0.380KV. Feeding such loads in the traditional ways like provision of Diesel-Powered Stations, installation of new distribution lines from the Feeding Centers, or building new Sub-Stations are not practical ways from the economical point of view, because it requires huge additional expenses and will increase electrical power losses. These expenses are not worthy for such loads and therefore, it is necessary to search for other methods to supply them. One of these methods is to use the lightning arrester line as capacitive divider to supply the light loads. In this research, the induced voltage of the lightning arrester line was calculated when it is isolated from the earth. We found the capacitance between lightning arrester line versus the phases and lightning arrester. It was also found the selective power out of the lightning arrester line and the required length which is to be isolated from the earth keeping the main function of the lightning arrester line. When economically comparing between supplying the light electrical loads by traditional ways and the method of lightning arrester, it was found the advantage of using lightning arresters to supply such loads. Also, by using the traditional methods, it was noted that there is a power loss in the power transmission lines by a percentage of 1.8%.

  7. Application of chaotic ant swarm optimization in electric load forecasting

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Wei-Chiang [Department of Information Management, Oriental Institute of Technology, 58, Section 2, Sichuan Rd., Panchiao, Taipei County 220 (China)

    2010-10-15

    Support vector regression (SVR) had revealed strong potential in accurate electric load forecasting, particularly by employing effective evolutionary algorithms to determine suitable values of its three parameters. Based on previous research results, however, these employed evolutionary algorithms themselves have several drawbacks, such as converging prematurely, reaching slowly the global optimal solution, and trapping into a local optimum. This investigation presents an SVR-based electric load forecasting model that applied a novel algorithm, namely chaotic ant swarm optimization (CAS), to improve the forecasting performance by searching its suitable parameters combination. The proposed CAS combines with the chaotic behavior of single ant and self-organization behavior of ant colony in the foraging process to overcome premature local optimum. The empirical results indicate that the SVR model with CAS (SVRCAS) results in better forecasting performance than the other alternative methods, namely SVRCPSO (SVR with chaotic PSO), SVRCGA (SVR with chaotic GA), regression model, and ANN model. (author)

  8. Forecasting Electrical Load Using a Multi-time-scale Approach

    OpenAIRE

    RINGWOOD John; Murray, F.T.

    1999-01-01

    This paper describes the application of a multi-time-scale technique to the modelling and forecasting of short-term electrical load. The multi-time-scale technique is based on adjusting the underlying short sampling period forecast time series with specific target points and possible aggregated demand. This allows not only improvement of the short sampling period forecast, but also focuses on weighting the accuracy of the forecast at certain critical points e.g. the ov...

  9. Coordinating plug-in electric vehicle charging with electric grid: Valley filling and target load following

    Science.gov (United States)

    Zhang, Li; Jabbari, Faryar; Brown, Tim; Samuelsen, Scott

    2014-12-01

    Plug-in electric vehicles (PEVs) shift energy consumption from petroleum to electricity for the personal transportation sector. This work proposes a decentralized charging protocol for PEVs with grid operators updating the cost signal. Each PEV calculates its own optimal charging profile only once based on the cost signal, after it is plugged in, and sends the result back to the grid operators. Grid operators only need to aggregate charging profiles and update the load and cost. The existing PEV characteristics, national household travel survey (NHTS), California Independent System Operator (CAISO) demand, and estimates for future renewable generation in California are used to simulate PEV operation, PEV charging profiles, grid demand, and grid net load (demand minus renewable). Results show the proposed protocol has good performance for overnight net load valley filling if the costs to be minimized are proportional to the net load. Annual results are shown in terms of overnight load variation and comparisons are made with grid level valley filling results. Further, a target load can be approached in the same manner by using the gap between current load and the target load as the cost. The communication effort involved is quite modest.

  10. Influence of Limitations on Possible Graph Ordinate Values of Electrical Load on Rated Values of Load Peaks and Troughs

    Directory of Open Access Journals (Sweden)

    I. V. Zhezhelenko

    2006-01-01

    Full Text Available The influence of limitations on possible theta-ordinate values of group non-uniform electrical load graphs on the rated values of theta peaks and theta troughs and, particularly, on the rated heating load value is considered in the paper. It is shown that neglect of limitations on graph theta- ordinates of an electrical load leads in some cases to errors in evaluation of load theta peaks and theta troughs that exceed the tolerable values by ±10 %.

  11. The control algorithm improving performance of electric load simulator

    Science.gov (United States)

    Guo, Chenxia; Yang, Ruifeng; Zhang, Peng; Fu, Mengyao

    2017-01-01

    In order to improve dynamic performance and signal tracking accuracy of electric load simulator, the influence of the moment of inertia, stiffness, friction, gaps and other factors on the system performance were analyzed on the basis of researching the working principle of load simulator in this paper. The PID controller based on Wavelet Neural Network was used to achieve the friction nonlinear compensation, while the gap inverse model was used to compensate the gap nonlinear. The compensation results were simulated by MATLAB software. It was shown that the follow-up performance of sine response curve of the system became better after compensating, the track error was significantly reduced, the accuracy was improved greatly and the system dynamic performance was improved.

  12. Load shift potential of electric vehicles in Europe

    Science.gov (United States)

    Babrowski, Sonja; Heinrichs, Heidi; Jochem, Patrick; Fichtner, Wolf

    2014-06-01

    Many governments highly encourage electric mobility today, aiming at a high market penetration. This development would bring forth an impact on the energy system, which strongly depends on the driving and charging behavior of the users. While an uncontrolled immediate charging might strain the local grid and/or higher peak loads, there are benefits to be gained by a controlled charging. We examine six European mobility studies in order to display the effects of controlled and uncontrolled unidirectional charging. Taking into account country-specific driving patterns, we generate for each country a charging load curve corresponding to uncontrolled charging and consider the corresponding parking time at charging facilities in order to identify load shift potentials. The main results are that besides the charging power of the vehicles, the possibility to charge at the work place has a significant influence on the uncontrolled charging curve. Neither national nor regional differences are as significant. When charging is only possible at home, the vehicle availability at charging facilities during the day for all countries is at least 24%. With the additional possibility to charge at work, at least 45% are constantly available. Accordingly, we identified a big potential for load shifting through controlled charging.

  13. HTGR-GT and electrical load integrated control

    Energy Technology Data Exchange (ETDEWEB)

    Chan, T.; Openshaw, F.; Pfremmer, D.

    1980-05-01

    A discussion of the control and operation of the HTGR-GT power plant is presented in terms of its closely coupled electrical load and core cooling functions. The system and its controls are briefly described and comparisons are made with more conventional plants. The results of analyses of selected transients are presented to illustrate the operation and control of the HTGR-GT. The events presented were specifically chosen to show the controllability of the plant and to highlight some of the unique characteristics inherent in this multiloop closed-cycle plant.

  14. Crack instability of ferroelectric solids under alternative electric loading

    Science.gov (United States)

    Chen, Hao-Sen; Wang, He-Ling; Pei, Yong-Mao; Wei, Yu-Jie; Liu, Bin; Fang, Dai-Ning

    2015-08-01

    The low fracture toughness of the widely used piezoelectric and ferroelectric materials in technological applications raises a big concern about their durability and safety. Up to now, the mechanisms of electric-field induced fatigue crack growth in those materials are not fully understood. Here we report experimental observations that alternative electric loading at high frequency or large amplitude gives rise to dramatic temperature rise at the crack tip of a ferroelectric solid. The temperature rise subsequently lowers the energy barrier of materials for domain switch in the vicinity of the crack tip, increases the stress intensity factor and leads to unstable crack propagation finally. In contrast, at low frequency or small amplitude, crack tip temperature increases mildly and saturates quickly, no crack growth is observed. Together with our theoretical analysis on the non-linear heat transfer at the crack tip, we constructed a safe operating area curve with respect to the frequency and amplitude of the electric field, and validated the safety map by experiments. The revealed mechanisms about how electro-thermal-mechanical coupling influences fracture can be directly used to guide the design and safety assessment of piezoelectric and ferroelectric devices.

  15. An electricity price model with consideration to load and gas price effects

    Institute of Scientific and Technical Information of China (English)

    黄民翔; 陶小虎; 韩祯祥

    2003-01-01

    Some characteristics of the electricity load and prices are studied, and the relationship between electricity prices and gas (fuel) prices is analyzed in this paper. Because electricity prices are strongly dependent on load and gas prices, the authors constructed a model for electricity prices based on the effects of these two factors; and used the Geometric Mean Reversion Brownian Motion (GMRBM) model to describe the electricity load process, and a Geometric Brownian Motion(GBM) model to describe the gas prices; deduced the price stochastic process model based on the above load model and gas price model. This paper also presents methods for parameters estimation, and proposes some methods to solve the model.

  16. On load flow control in electric power systems

    Energy Technology Data Exchange (ETDEWEB)

    Herbig, Arnim

    2000-01-01

    This dissertation deals with the control of active power flow, or load flow in electric power systems. During the last few years, interest in the possibilities to control the active power flows in transmission systems has increased significantly. There is a number of reasons for this, coming both from the application side - that is, from power system operations - and from the technological side. where advances in power electronics and related technologies have made new system components available. Load flow control is by nature a multi-input multi-output problem, since any change of load flow in one line will be complemented by changes in other lines. Strong cross-coupling between controllable components is to be expected, and the possibility of adverse interactions between these components cannot be rejected straightaway. Interactions with dynamic phenomena in the power system are also a source of concern. Three controllable components are investigated in this thesis, namely the controlled series capacitor (CSC), the phase angle regulator (PAR), and the unified power flow controller (UPFC). Properties and characteristics of these devices axe investigated and discussed. A simple control strategy is proposed. This strategy is then analyzed extensively. Mathematical methods and physical knowledge about the pertinent phenomena are combined, and it is shown that this control strategy can be used for a fairly general class of devices. Computer simulations of the controlled system provide insight into the system behavior in a system of reasonable size. The robustness and stability of the control system are discussed as are its limits. Further, the behavior of the control strategy in a system where the modeling allows for dynamic phenomena are investigated with computer simulations. It is discussed under which circumstances the control action has beneficial or detrimental effect on the system dynamics. Finally, a graphical approach for analyzing the effect of controllers

  17. Impacts of rising air temperatures on electric transmission ampacity and peak electricity load in the United States

    Science.gov (United States)

    Bartos, Matthew; Chester, Mikhail; Johnson, Nathan; Gorman, Brandon; Eisenberg, Daniel; Linkov, Igor; Bates, Matthew

    2016-11-01

    Climate change may constrain future electricity supply adequacy by reducing electric transmission capacity and increasing electricity demand. The carrying capacity of electric power cables decreases as ambient air temperatures rise; similarly, during the summer peak period, electricity loads typically increase with hotter air temperatures due to increased air conditioning usage. As atmospheric carbon concentrations increase, higher ambient air temperatures may strain power infrastructure by simultaneously reducing transmission capacity and increasing peak electricity load. We estimate the impacts of rising ambient air temperatures on electric transmission ampacity and peak per-capita electricity load for 121 planning areas in the United States using downscaled global climate model projections. Together, these planning areas account for roughly 80% of current peak summertime load. We estimate climate-attributable capacity reductions to transmission lines by constructing thermal models of representative conductors, then forcing these models with future temperature projections to determine the percent change in rated ampacity. Next, we assess the impact of climate change on electricity load by using historical relationships between ambient temperature and utility-scale summertime peak load to estimate the extent to which climate change will incur additional peak load increases. We find that by mid-century (2040-2060), increases in ambient air temperature may reduce average summertime transmission capacity by 1.9%-5.8% relative to the 1990-2010 reference period. At the same time, peak per-capita summertime loads may rise by 4.2%-15% on average due to increases in ambient air temperature. In the absence of energy efficiency gains, demand-side management programs and transmission infrastructure upgrades, these load increases have the potential to upset current assumptions about future electricity supply adequacy.

  18. Empirical Investigations of the Opportunity Limits of Automatic Residential Electric Load Shaping

    Energy Technology Data Exchange (ETDEWEB)

    Cruickshank, Robert F.; Henze, Gregor P.; Balaji, Rajagopalan; Hodge, Bri-Mathias S.; Florita, Anthony R.

    2017-05-11

    Residential electric load shaping is often modeled as infrequent, utility-initiated, short-duration deferral of peak demand through direct load control. In contrast, modeled herein is the potential for frequent, transactive, intraday, consumer-configurable load shaping for storage-capable thermostatically controlled electric loads (TCLs), including refrigerators, freezers, and hot water heaters. Unique to this study are 28 months of 15-minute-interval observations of usage in 101 homes in the Pacific Northwest United States that specify exact start, duration, and usage patterns of approximately 25 submetered loads per home. The magnitudes of the load shift from voluntarily-participating TCL appliances are aggregated to form hourly upper and lower load-shaping limits for the coordination of electrical generation, transmission, distribution, storage, and demand. Empirical data are statistically analyzed to define metrics that help quantify load-shaping opportunities.

  19. Empirical Investigations of the Opportunity Limits of Automatic Residential Electric Load Shaping: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Cruickshank, Robert F.; Henze, Gregor P.; Balaji, Rajagopalan; Hodge, Bri-Mathias S.; Florita, Anthony R.

    2017-04-01

    Residential electric load shaping is often modeled as infrequent, utility-initiated, short-duration deferral of peak demand through direct load control. In contrast, modeled herein is the potential for frequent, transactive, intraday, consumer-configurable load shaping for storage-capable thermostatically controlled electric loads (TCLs), including refrigerators, freezers, and hot water heaters. Unique to this study are 28 months of 15-minute-interval observations of usage in 101 homes in the Pacific Northwest United States that specify exact start, duration, and usage patterns of approximately 25 submetered loads per home. The magnitudes of the load shift from voluntarily-participating TCL appliances are aggregated to form hourly upper and lower load-shaping limits for the coordination of electrical generation, transmission, distribution, storage, and demand. Empirical data are statistically analyzed to define metrics that help quantify load-shaping opportunities.

  20. Support Vector Regression Model Based on Empirical Mode Decomposition and Auto Regression for Electric Load Forecasting

    Directory of Open Access Journals (Sweden)

    Hong-Juan Li

    2013-04-01

    Full Text Available Electric load forecasting is an important issue for a power utility, associated with the management of daily operations such as energy transfer scheduling, unit commitment, and load dispatch. Inspired by strong non-linear learning capability of support vector regression (SVR, this paper presents a SVR model hybridized with the empirical mode decomposition (EMD method and auto regression (AR for electric load forecasting. The electric load data of the New South Wales (Australia market are employed for comparing the forecasting performances of different forecasting models. The results confirm the validity of the idea that the proposed model can simultaneously provide forecasting with good accuracy and interpretability.

  1. Summary of Market Opportunities for Electric Vehicles and Dispatchable Load in Electrolyzers

    Energy Technology Data Exchange (ETDEWEB)

    Denholm, Paul [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Eichman, Joshua [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Markel, Tony [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Ma, Ookie [U.S Department of Energy, Washington, DC (United States)

    2015-05-19

    Electric vehicles (EVs) and electrolyzers are potentially significant sources of new electric loads. Both are flexible in that the amount of electricity consumed can be varied in response to a variety of factors including the cost of electricity. Because both EVs and electrolyzers can control the timing of electricity purchases, they can minimize energy costs by timing the purchases of energy to periods of lowest costs.

  2. artificial neural network (ann) approach to electrical load

    African Journals Online (AJOL)

    2004-08-18

    Aug 18, 2004 ... short term hourly load forecasts has a significant impact on the economic ... other peaking plants such as gas turbines. The ... load, usually into basic and weather dependent ... as sudden weather or special events. ANN can ...

  3. Daily peak electricity load forecasting in South Africa using a ...

    African Journals Online (AJOL)

    major source of variation in peak demand forecasting and the inclusion of temperature has a significant ... This definition of electrical demand has its weaknesses. Electrical ..... The coefficient of t is positive, showing a positive linear trend.

  4. A cooling change-point model of community-aggregate electrical load

    Energy Technology Data Exchange (ETDEWEB)

    Ali, Muhammad Tauha; Mokhtar, Marwan; Chiesa, Matteo; Armstrong, Peter [Mechanical Engineering Program, Masdar Institute of Science and Technology, PO Box 54224, Abu Dhabi (United Arab Emirates)

    2011-01-15

    Estimates of daily electrical cooling load for a city of 800,000 are developed based on the relationship between weather variables and daily-average electricity consumption over 1 year. The relationship is found to be nearly linear above a threshold temperature. Temperature and humidity were found to be the largest, at 59%, and second largest, at 21%, contributors to electrical cooling load. Direct normal irradiation intercepted by a vertical cylinder, DNI sin {theta}, was found to be a useful explanatory variable when modeling aggregates of buildings without a known or dominant orientation. The best study case model used DNI sin {theta} and diffuse horizontal irradiation (DHI) as distinct explanatory variables with annual electrical cooling load contributions of 9% and 11% respectively. Although the seasonal variation in electrical cooling load is large - on peak summer days more than 1.5 times the winter base load - the combined direct and diffuse solar contribution is essentially flat through the year, a condition at odds with the common assumption that solar cooling always provides a good match between supply and demand. The final model gives an electrical cooling load estimate for Abu Dhabi Island that corresponds to 40% of the total annual electrical load and 61% on the peak day. (author)

  5. An electricity price model with consideration to load and gas price effects

    Institute of Scientific and Technical Information of China (English)

    黄民翔; 陶小虎; 韩祯祥

    2003-01-01

    Some characteristics of the electricity load and prices are studied, and the relationship between electricity prices and gas (fnel) prices is analyzed in this paper. Because electricity prices are strongly depen-dent on load and gas prices, the authors constructed a model for electricity prices based on the effects of these two factors; and used the Geometric Mean Reversion Brownian Motion (GMRBM) model to describe the electricity load process, and a Geometric Brownian Motion(GBM) model to describe the gas prices ; deduced the price stochastic process model based on the above load model and gas price model. This paper also presents methods for parameters estimation, and proposes some methods to solve the model.

  6. Impacts of Electric Vehicle Loads on Power Distribution Systems

    DEFF Research Database (Denmark)

    Pillai, Jayakrishnan Radhakrishna; Bak-Jensen, Birgitte

    2010-01-01

    Electric vehicles (EVs) are the most promising alternative to replace a significant amount of gasoline vehicles to provide cleaner, CO2 free and climate friendly transportation. On integrating more electric vehicles, the electric utilities must analyse the related impacts on the electricity syste...... be accommodated in the network with the smart charging mode. The extent of integrating EVs in an area is constrained by the EV charging behavior and the safe operational limits of electricity system parameters....... operation. This paper investigates the effects on the key power distribution system parameters like voltages, line drops, system losses etc. by integrating electric vehicles in the range of 0-50% of the cars with different charging capacities. The dump as well as smart charging modes of electric vehicles......Electric vehicles (EVs) are the most promising alternative to replace a significant amount of gasoline vehicles to provide cleaner, CO2 free and climate friendly transportation. On integrating more electric vehicles, the electric utilities must analyse the related impacts on the electricity system...

  7. Long-term forecasting of hourly electricity load: Identification of consumption profiles and segmentation of customers

    DEFF Research Database (Denmark)

    Møller Andersen, Frits; Larsen, Helge V.; Boomsma, Trine Krogh

    2013-01-01

    Data for aggregated hourly electricity demand shows systematic variations over the day, week, and seasons, and forecasting of aggregated hourly electricity load has been the subject of many studies. With hourly metering of individual customers, data for individual consumption profiles is availabl...... as the shares of consumption by categories of customers change and new consumption technologies such as electrical vehicles and (for Denmark in particular) individual heat pumps are introduced. © 2013 Elsevier Ltd. All rights reserved.......Data for aggregated hourly electricity demand shows systematic variations over the day, week, and seasons, and forecasting of aggregated hourly electricity load has been the subject of many studies. With hourly metering of individual customers, data for individual consumption profiles is available....... Using this data and analysing the case of Denmark, we show that consumption profiles for categories of customers are equally systematic but very different for distinct categories, that is, distinct categories of customers contribute differently to the aggregated electricity load profile. Therefore...

  8. Modeling and Analysis of Commercial Building Electrical Loads for Demand Side Management

    Science.gov (United States)

    Berardino, Jonathan

    In recent years there has been a push in the electric power industry for more customer involvement in the electricity markets. Traditionally the end user has played a passive role in the planning and operation of the power grid. However, many energy markets have begun opening up opportunities to consumers who wish to commit a certain amount of their electrical load under various demand side management programs. The potential benefits of more demand participation include reduced operating costs and new revenue opportunities for the consumer, as well as more reliable and secure operations for the utilities. The management of these load resources creates challenges and opportunities to the end user that were not present in previous market structures. This work examines the behavior of commercial-type building electrical loads and their capacity for supporting demand side management actions. This work is motivated by the need for accurate and dynamic tools to aid in the advancement of demand side operations. A dynamic load model is proposed for capturing the response of controllable building loads. Building-specific load forecasting techniques are developed, with particular focus paid to the integration of building management system (BMS) information. These approaches are tested using Drexel University building data. The application of building-specific load forecasts and dynamic load modeling to the optimal scheduling of multi-building systems in the energy market is proposed. Sources of potential load uncertainty are introduced in the proposed energy management problem formulation in order to investigate the impact on the resulting load schedule.

  9. Electric Power Load Analysis (EPLA) for Surface Ships

    Science.gov (United States)

    2012-09-17

    ESM can be based on a host of technologies to include batteries, flywheels , and ultra-capacitors. Energy storage can be provided for use in a...electrical generation, energy storage , and power conversion components and equipment and current requirements for electrical distribution equipment and...Demand factor 4 3.7 Demand power 4 3.8 Electric and propulsion plant concept of operations 4 3.9 Emergency ship control 4 3.10 Energy storage

  10. Detection of Periodic Beacon Loads in Electrical Distribution Substation Data

    Energy Technology Data Exchange (ETDEWEB)

    Hammerstrom, Donald J.; Guttromson, Ross T.; Lu, Ning; Boyd, Paul A.; Trudnowski, Daniel; Chassin, David P.; Bonebrake, Christopher A.; Shaw, James M.

    2006-05-31

    This research explores methods for identifying a whether a load is sending a signal to the utility SCADA system. Such a system can identify whether various loads are signialing using existing SCADA infrastructure, that is, without added, high cost communications infrastructure.

  11. Short-Term Load Forecasting Based on the Analysis of User Electricity Behavior

    Directory of Open Access Journals (Sweden)

    Yuancheng Li

    2016-11-01

    Full Text Available The smart meter is an important part of the smart grid, and in order to take full advantage of smart meter data, this paper mines the electricity behaviors of smart meter users to improve the accuracy of load forecasting. First, the typical day loads of users are calculated separately according to different date types (ordinary workdays, day before holidays, holidays. Second, the similarity between user electricity behaviors is mined and the user electricity loads are clustered to classify the users with similar behaviors into the same cluster. Finally, the load forecasting model based on the Online Sequential Extreme Learning Machine (OS-ELM is applied to different clusters to conduct load forecasting and the load forecast is summed to obtain the system load. In order to prove the validity of the proposed method, we performed simulation experiments on the MATLAB platform using smart meter data from the Ireland electric power cooperation. The experimental results show that the proposed method is able to mine the user electricity behaviors deeply, improve the accuracy of load forecasting by the reasonable clustering of users, and reveal the relationship between forecasting accuracy and cluster numbers.

  12. Research in Residential Electricity Characteristics and Short-Term Load Forecasting

    Directory of Open Access Journals (Sweden)

    Haixia Feng

    2013-07-01

    Full Text Available In this paper we make research in Residential short-term load forecasting. Different application scenes have different affecting factors of short-term load, so we should specifically analysis of factors that affect the load of the residential electricity. We use SPSS (Statistic Package for Social Science to figure out the relationship between the daily load and temperature, weather conditions and other factors, finding the main factors among the impacting factors, and analyzing residential electricity consumption habits and load characteristics. Then, the paper introduces the common prediction methods. Combining with the above analysis to choose short-term load forecasting methods for residential users, we create automatic linear regression model and artificial neural network model to predict the future electricity load, calculating the residual between the predicted values and the actual values and mean square deviation of the values, and evaluating the accuracy of the load forecasting. The results prove that automatic linear regression model is effective in residential short-term electricity load forecasting.

  13. The Effect of External Factors on Consumption Electricity Loads Forecasting using Fuzzy Takagi-Sugeno Kang

    National Research Council Canada - National Science Library

    Gayatri Dwi Santika; wayan f mahmudy

    2017-01-01

    .... The results of the study came to the conclusion that Fuzzy Inference System Sugeno method using external factors to forecast the consumption of electrical load gives a better result than Fuzzy...

  14. Wind farm electrical power production model for load flow analysis

    Energy Technology Data Exchange (ETDEWEB)

    Segura-Heras, Isidoro; Escriva-Escriva, Guillermo; Alcazar-Ortega, Manuel [Institute for Energy Engineering, Universidad Politecnica de Valencia, Camino de Vera, s/n, edificio 8E, escalera F, 2a planta, 46022 Valencia (Spain)

    2011-03-15

    The importance of renewable energy increases in activities relating to new forms of managing and operating electrical power: especially wind power. Wind generation is increasing its share in the electricity generation portfolios of many countries. Wind power production in Spain has doubled over the past four years and has reached 20 GW. One of the greatest problems facing wind farms is that the electrical power generated depends on the variable characteristics of the wind. To become competitive in a liberalized market, the reliability of wind energy must be guaranteed. Good local wind forecasts are therefore essential for the accurate prediction of generation levels for each moment of the day. This paper proposes an electrical power production model for wind farms based on a new method that produces correlated wind speeds for various wind farms. This method enables a reliable evaluation of the impact of new wind farms on the high-voltage distribution grid. (author)

  15. Selection of Pedaling Load and Design of Electric-Cart Control System with Continuously Adjustable Pedal Load

    Science.gov (United States)

    She, Jin-Hua; Ishii, Shota; Yokota, Sho; Sakuma, Yuji; Ohyama, Yasuhiro

    A previously developed electric cart was improved by installing a knob that allows the driver to continuously vary the pedal load between the strenuous and assisted modes. This paper explains how the pedal load is determined and a design method for the cart control system. First, the largest pedal load is determined from the standpoint of ergonomics on the basis of the rating of perceived exertion and the Karvonen formula with a special focus on the motor function of the elderly. Then, a gain-scheduling cart control system for any pedal load in the allowed range is described, and a stability condition is derived using dynamic parallel distributed compensation. Experimental results demonstrate the validity of the cart control system.

  16. Analysis of thermal characteristics of electrical wiring for load groups in cattle barns.

    Science.gov (United States)

    Kim, Doo Hyun; Yoo, Sang-Ok; Kim, Sung Chul; Hwang, Dong Kyu

    2015-01-01

    The purpose of the current study is to analyze the thermal characteristics of electrical wirings depending on the number of operating load by connecting four types of electrical wirings that are selected by surveying the conditions for the electric fans, automatic waterers and halogen warm lamps that were installed in cattle barns in different years. The conditions of 64 cattle barns were surveyed and an experimental test was conducted at a cattle barn. The condition-survey covered inappropriate design, construction and misuse of electrical facility, including electrical wiring mostly used, and the mode of load current was evaluated. The survey showed that the mode of load current increased as the installation year of the fans, waterers and halogen lamps became older. Accordingly, the cattle barn manager needed to increase the capacity of the circuit breaker, which promoted the degradation of insulation of the electrical wires' sheath and increased possibility for electrical fires in the long-run. The test showed that the saturation temperature of the wire insulated sheath increased depending on the installation year of the load groups, in case of VCTFK and VFF electric wires, therefore, requiring their careful usage in the cattle barns.

  17. Letter to the Editor: Electric Vehicle Demand Model for Load Flow Studies

    DEFF Research Database (Denmark)

    Garcia-Valle, Rodrigo; Vlachogiannis, Ioannis (John)

    2009-01-01

    This paper introduces specific and simple model for electric vehicles suitable for load flow studies. The electric vehicles demand system is modelled as PQ bus with stochastic characteristics based on the concept of queuing theory. All appropriate variables of stochastic PQ buses are given...

  18. Modelling the Load Torques of Electric Drive for Polymerization Process

    Directory of Open Access Journals (Sweden)

    Andrzej Popenda

    2007-01-01

    Full Text Available The problems of mathematical modelling the load torques on shaft of driving motor designed for applications in polymerization reactors are presented in the paper. The real load of polymerization drive is determined as a function of angular velocity. Mentioned function results from friction in roll-formed slide bearing as well as from friction of ethylene molecules with mixer arms in polymerization reactor chamber. Application of mathematical formulas concerning the centrifugal ventilator is proposed to describe the mixer in reactor chamber. The analytical formulas describing the real loads of polymerization drive are applied in mathematical modelling the power unit of polymerization reactor with specially designed induction motor. The numerical analysis of transient states was made on the basis of formulated mathematical model. Examples of transient responses and trajectories resulting from analysis are presented in the paper.

  19. Small Signal Stability Improvement of Power Systems Using Optimal Load Responses in Competitive Electricity Markets

    DEFF Research Database (Denmark)

    Hu, Weihao; Su, Chi; Chen, Zhe;

    2011-01-01

    Since the hourly spot market price is available one day ahead in Denmark, the price could be transferred to the consumers and they may shift some of their loads from high price periods to the low price periods in order to save their energy costs. The optimal load response to an electricity price...... price is proposed. A 17-bus power system with high wind power penetrations, which resembles the Eastern Danish power system, is chosen as the study case. Simulation results show that the optimal load response to electricity prices is an effective measure to improve the small signal stability of power...

  20. Performance of fuzzy approach in Malaysia short-term electricity load forecasting

    Science.gov (United States)

    Mansor, Rosnalini; Zulkifli, Malina; Yusof, Muhammad Mat; Ismail, Mohd Isfahani; Ismail, Suzilah; Yin, Yip Chee

    2014-12-01

    Many activities such as economic, education and manafucturing would paralyse with limited supply of electricity but surplus contribute to high operating cost. Therefore electricity load forecasting is important in order to avoid shortage or excess. Previous finding showed festive celebration has effect on short-term electricity load forecasting. Being a multi culture country Malaysia has many major festive celebrations such as Eidul Fitri, Chinese New Year and Deepavali but they are moving holidays due to non-fixed dates on the Gregorian calendar. This study emphasis on the performance of fuzzy approach in forecasting electricity load when considering the presence of moving holidays. Autoregressive Distributed Lag model was estimated using simulated data by including model simplification concept (manual or automatic), day types (weekdays or weekend), public holidays and lags of electricity load. The result indicated that day types, public holidays and several lags of electricity load were significant in the model. Overall, model simplification improves fuzzy performance due to less variables and rules.

  1. Hybrid partial least squares and neural network approach for short-term electrical load forecasting

    Institute of Scientific and Technical Information of China (English)

    Shukang YANG; Ming LU; Huifeng XUE

    2008-01-01

    Intelligent systems and methods such as the neural network (NN) are usually used in electric power systems for short-term electrical load forecasting. However, a vast amount of electrical load data is often redundant, and linearly or nonlinearly correlated with each other. Highly correlated input data can result in erroneous prediction results given out by an NN model. Besides this, the determination of the topological structure of an NN model has always been a problem for designers. This paper presents a new artificial intelligence hybrid procedure for next day electric load forecasting based on partial least squares (PLS) and NN. PLS is used for the compression of data input space, and helps to determine the structure of the NN model. The hybrid PLS-NN model can be used to predict hourly electric load on weekdays and weekends. The advantage of this methodology is that the hybrid model can provide faster convergence and more precise prediction results in comparison with abductive networks algorithm. Extensive testing on the electrical load data of the Puget power utility in the USA confirms the validity of the proposed approach.

  2. Using adaptive network based fuzzy inference system to forecast regional electricity loads

    Energy Technology Data Exchange (ETDEWEB)

    Ying, Li-Chih [Department of Marketing Management, Central Taiwan University of Science and Technology, 11, Pu-tzu Lane, Peitun, Taichung City 406 (China); Pan, Mei-Chiu [Graduate Institute of Management Sciences, Nanhua University, 32, Chung Keng Li, Dalin, Chiayi 622 (China)

    2008-02-15

    Since accurate regional load forecasting is very important for improvement of the management performance of the electric industry, various regional load forecasting methods have been developed. The purpose of this study is to apply the adaptive network based fuzzy inference system (ANFIS) model to forecast the regional electricity loads in Taiwan and demonstrate the forecasting performance of this model. Based on the mean absolute percentage errors and statistical results, we can see that the ANFIS model has better forecasting performance than the regression model, artificial neural network (ANN) model, support vector machines with genetic algorithms (SVMG) model, recurrent support vector machines with genetic algorithms (RSVMG) model and hybrid ellipsoidal fuzzy systems for time series forecasting (HEFST) model. Thus, the ANFIS model is a promising alternative for forecasting regional electricity loads. (author)

  3. Common long-range dependence in a panel of hourly Nord Pool electricity prices and loads

    DEFF Research Database (Denmark)

    Ergemen, Yunus Emre; Haldrup, Niels; Rodríguez-Caballero, Carlos Vladimir

    of the underlying production technology and because the demand is more volatile than the supply, equilibrium prices and loads are argued to identify the periodic power supply curve. The estimated supply elasticities are estimated from fractionally co-integrated relations and range between 0.5 and 1......Equilibrium electricity spot prices and loads are often determined simultaneously in a day-ahead auction market for each hour of the subsequent day. Hence daily observations of hourly prices take the form of a periodic panel rather than a time series of hourly observations. We consider novel panel...... data approaches to analyse the time series and the cross-sectional dependence of hourly Nord Pool electricity spot prices and loads for the period 2000-2013. Hourly electricity prices and loads data are characterized by strong serial long-range dependence in the time series dimension in addition...

  4. Electricity's "Disappearing Act": Understanding Energy Consumption and Phantom Loads

    Science.gov (United States)

    Rusk, Bryan; Mahfouz, Tarek; Jones, James

    2011-01-01

    Energy exists in many forms and can be converted from one form to another. However, this conversion is not 100% efficient, and energy is lost in the form of heat during conversion. In addition, approximately 6% of the monthly consumption of the average American household's electricity is neither lost nor used by its residents. These losses are…

  5. Electricity's "Disappearing Act": Understanding Energy Consumption and Phantom Loads

    Science.gov (United States)

    Rusk, Bryan; Mahfouz, Tarek; Jones, James

    2011-01-01

    Energy exists in many forms and can be converted from one form to another. However, this conversion is not 100% efficient, and energy is lost in the form of heat during conversion. In addition, approximately 6% of the monthly consumption of the average American household's electricity is neither lost nor used by its residents. These losses are…

  6. Study on Impact of Electric Vehicles Charging Models on Power Load

    Science.gov (United States)

    Cheng, Chen; Hui-mei, Yuan

    2017-05-01

    With the rapid increase in the number of electric vehicles, which will lead the power load on grid increased and have an adversely affect. This paper gives a detailed analysis of the following factors, such as scale of the electric cars, charging mode, initial charging time, initial state of charge, charging power and other factors. Monte Carlo simulation method is used to compare the two charging modes, which are conventional charging and fast charging, and MATLAB is used to model and simulate the electric vehicle charging load. The results show that compared with the conventional charging mode, fast charging mode can meet the requirements of fast charging, but also bring great load to the distribution network which will affect the reliability of power grid.

  7. Hybridizing DEMD and Quantum PSO with SVR in Electric Load Forecasting

    Directory of Open Access Journals (Sweden)

    Li-Ling Peng

    2016-03-01

    Full Text Available Electric load forecasting is an important issue for a power utility, associated with the management of daily operations such as energy transfer scheduling, unit commitment, and load dispatch. Inspired by strong non-linear learning capability of support vector regression (SVR, this paper presents an SVR model hybridized with the differential empirical mode decomposition (DEMD method and quantum particle swarm optimization algorithm (QPSO for electric load forecasting. The DEMD method is employed to decompose the electric load to several detail parts associated with high frequencies (intrinsic mode function—IMF and an approximate part associated with low frequencies. Hybridized with quantum theory to enhance particle searching performance, the so-called QPSO is used to optimize the parameters of SVR. The electric load data of the New South Wales (Sydney, Australia market and the New York Independent System Operator (NYISO, New York, USA are used for comparing the forecasting performances of different forecasting models. The results illustrate the validity of the idea that the proposed model can simultaneously provide forecasting with good accuracy and interpretability.

  8. Load area aggregation considering integration of electric vehicles to the system

    Directory of Open Access Journals (Sweden)

    L. F. Rodríguez Garcia

    2015-11-01

    Full Text Available Current electric power systems have an increasing penetration of electric vehicles, and its effect has to be considered in different studies, such as optimal dispatch or voltage stability, among others. Additionally, considering that power system analysis becomes complex when the number of buses increase, this paper presents a methodology for aggregation of load areas that use a measurement-based load modeling approach based on an evolutionary computational technique and a classical reduction method. This aggregate load area model is proposed to reduce areas that ddconsider electric vehicle (EV load models. The proposed method provides a static equivalent load model and an equivalent network that can be used to reduce the computational effort required by power system studies. In order to validate the application of the proposed methodology, a 30-bus power system considering several disturbances and levels of penetration of the electric vehicles was used. The results show that the equivalent network model allows the reproduction of different events with an acceptable accuracy when it is compared to the original system behavior.

  9. On the road performance tests of electric test vehicle for correlation with road load simulator

    Science.gov (United States)

    Dustin, M. O.; Slavik, R. J.

    1982-08-01

    A dynamometer (road load simulator) is used to test and evaluate electric vehicle propulsion systems. To improve correlation between system tests on the road load simulator and on the road, similar performance tests are conducted using the same vehicle. The results of track tests on the electric propulsion system test vehicle are described. The tests include range at constant speeds and over SAE J227a driving cycles, maximum accelerations, maximum gradability, and tire rolling resistance determination. Road power requirements and energy consumption were also determined from coast down tests.

  10. A SIMPLE CONSTITUTIVE MODEL FOR FERROELECTRIC CERAMICS UNDER ELECTRICAL/MECHANICAL LOADING

    Institute of Scientific and Technical Information of China (English)

    Yu Li; Yu Shouwen; Feng Xiqiao

    2007-01-01

    A simple phenomenological model is developed for describing the macroscopic constitutive response of ferroelectric materials based on consideration of the fact that domain switching is a progressive evolution process with loading. The volume fraction of domain switching is taken as an internal variable, which is derived from the domain nucleation theory. The proposed theory can simulate the dielectric hysteresis, reversed butterfly hysteresis, nonlinear strain-stress hysteresis, as well as electric displacement-stress relation of ferroelectric materials. Its comparison with experimental results and two other theoretical models reveals that the model presented can well predict the nonlinear hysteresis of ferroelectrics under electrical or mechanical loading.

  11. Electrical Response of Cement-Based Piezoelectric Ceramic Composites under Mechanical Loadings

    Directory of Open Access Journals (Sweden)

    Biqin Dong

    2011-01-01

    Full Text Available Electrical responses of cement-based piezoelectric ceramic composites under mechanical loadings are studied. A simple high order model is presented to explain the nonlinear phenomena, which is found in the electrical response of the composites under large mechanical loadings. For general situation, this nonlinear piezoelectric effect is quite small, and the composite is suitable for dynamic mechanical sensor as holding high static stability. The experimental results are consistent with the relationship quite well. The study shows that cement-based piezoelectric composite is suitable for potential application as dynamic mechanical sensor with excellent dynamic response and high static stability.

  12. The Effect of External Factors on Consumption Electricity Loads Forecasting using Fuzzy Takagi-Sugeno Kang

    Directory of Open Access Journals (Sweden)

    Gayatri Dwi Santika

    2017-03-01

    Full Text Available This study applied Fuzzy Inference System Sugeno to forecast electrical load by considering the external factors. To see the accuracy of forecasting using Fuzzy Inference System Sugeno, then a comparison between the forecasting results of Fuzzy Inference System Sugeno using historical data with Fuzzy Inference System Sugeno using external factors was done. By using external factors method, resulted the smallest RMSE of 0762 and using historical data obtained error (RMSE of 1028. The results of the study came to the conclusion that Fuzzy Inference System Sugeno method using external factors to forecast the consumption of electrical load gives a better result than Fuzzy Inference System Sugeno using only historical data.

  13. Climate Control Load Reduction Strategies for Electric Drive Vehicles in Warm Weather

    Energy Technology Data Exchange (ETDEWEB)

    Jeffers, M. A.; Chaney, L.; Rugh, J. P.

    2015-04-30

    Passenger compartment climate control is one of the largest auxiliary loads on a vehicle. Like conventional vehicles, electric vehicles (EVs) require climate control to maintain occupant comfort and safety, but cabin heating and air conditioning have a negative impact on driving range for all electric vehicles. Range reduction caused by climate control and other factors is a barrier to widespread adoption of EVs. Reducing the thermal loads on the climate control system will extend driving range, thereby reducing consumer range anxiety and increasing the market penetration of EVs. Researchers at the National Renewable Energy Laboratory have investigated strategies for vehicle climate control load reduction, with special attention toward EVs. Outdoor vehicle thermal testing was conducted on two 2012 Ford Focus Electric vehicles to evaluate thermal management strategies for warm weather, including solar load reduction and cabin pre-ventilation. An advanced thermal test manikin was used to assess a zonal approach to climate control. In addition, vehicle thermal analysis was used to support testing by exploring thermal load reduction strategies, evaluating occupant thermal comfort, and calculating EV range impacts. Through stationary cooling tests and vehicle simulations, a zonal cooling configuration demonstrated range improvement of 6%-15%, depending on the drive cycle. A combined cooling configuration that incorporated thermal load reduction and zonal cooling strategies showed up to 33% improvement in EV range.

  14. A New Two-Stage Approach to Short Term Electrical Load Forecasting

    Directory of Open Access Journals (Sweden)

    Dragan Tasić

    2013-04-01

    Full Text Available In the deregulated energy market, the accuracy of load forecasting has a significant effect on the planning and operational decision making of utility companies. Electric load is a random non-stationary process influenced by a number of factors which make it difficult to model. To achieve better forecasting accuracy, a wide variety of models have been proposed. These models are based on different mathematical methods and offer different features. This paper presents a new two-stage approach for short-term electrical load forecasting based on least-squares support vector machines. With the aim of improving forecasting accuracy, one more feature was added to the model feature set, the next day average load demand. As this feature is unknown for one day ahead, in the first stage, forecasting of the next day average load demand is done and then used in the model in the second stage for next day hourly load forecasting. The effectiveness of the presented model is shown on the real data of the ISO New England electricity market. The obtained results confirm the validity advantage of the proposed approach.

  15. Load management in electrical networks. Objectives, methods, prospects; Gestion de la charge du reseau electrique. Objectifs, methodes, perspectives

    Energy Technology Data Exchange (ETDEWEB)

    Gabioud, D.

    2008-07-01

    This illustrated article takes up the problems related to the variation of the load in electricity networks. How to handle the peak load? Different solutions in the energy demand management are discussed. Method based on the price, method based on the reduction of the load by electric utilities. Information systems are presented which gives the consumer the needed data to participate in the local load management.

  16. Load forecast method of electric vehicle charging station using SVR based on GA-PSO

    Science.gov (United States)

    Lu, Kuan; Sun, Wenxue; Ma, Changhui; Yang, Shenquan; Zhu, Zijian; Zhao, Pengfei; Zhao, Xin; Xu, Nan

    2017-06-01

    This paper presents a Support Vector Regression (SVR) method for electric vehicle (EV) charging station load forecast based on genetic algorithm (GA) and particle swarm optimization (PSO). Fuzzy C-Means (FCM) clustering is used to establish similar day samples. GA is used for global parameter searching and PSO is used for a more accurately local searching. Load forecast is then regressed using SVR. The practical load data of an EV charging station were taken to illustrate the proposed method. The result indicates an obvious improvement in the forecasting accuracy compared with SVRs based on PSO and GA exclusively.

  17. Management of electricity peak load for residential sector in Baghdad city by using solar generation

    Directory of Open Access Journals (Sweden)

    Afaneen A. Abbood, Mohammed A. Salih, Hasan N. Muslim

    2017-01-01

    Full Text Available Load management strategies such as peak reduction, load shifting and energy conservation are effective solution to save and optimally usage of electricity. Solar cells - photovoltaic systems (solar PV are one of the modern methods used in the management of peak loads in the electric power system because PV generation coincides with peak load hours in the day. The aim of this work is implementation of management techniques using solar cells for residential sector in Baghdad city. The estimation of solar radiation data and PV system design has been simulated based on MATLAB software. In this study, a 20% efficiency monocrystalline silicon rooftop PV generator of 2kWp with six panels and overall area 10m² has been proposed for each customer in the residential sector of Baghdad. The panels are orientated towards south (azimuth angle equals zero with a tilt angle equals 18° for summery months and 48° for wintery months. The obtained results of demand saving range between 17% for January and 27% for April while 20% for June. The annually demand saving for each consumer is 20%. As well as to the demand saving, this study presents the capability of application the load-shifting technique from high load periods to low load periods, and ability to store the surplus energy produced from PV generator in batteries for usage this energy at a later time.

  18. Method and system employing finite state machine modeling to identify one of a plurality of different electric load types

    Energy Technology Data Exchange (ETDEWEB)

    Du, Liang; Yang, Yi; Harley, Ronald Gordon; Habetler, Thomas G.; He, Dawei

    2016-08-09

    A system is for a plurality of different electric load types. The system includes a plurality of sensors structured to sense a voltage signal and a current signal for each of the different electric loads; and a processor. The processor acquires a voltage and current waveform from the sensors for a corresponding one of the different electric load types; calculates a power or current RMS profile of the waveform; quantizes the power or current RMS profile into a set of quantized state-values; evaluates a state-duration for each of the quantized state-values; evaluates a plurality of state-types based on the power or current RMS profile and the quantized state-values; generates a state-sequence that describes a corresponding finite state machine model of a generalized load start-up or transient profile for the corresponding electric load type; and identifies the corresponding electric load type.

  19. Design of a Load Torque Based Control Strategy for Improving Electric Tractor Motor Energy Conversion Efficiency

    Directory of Open Access Journals (Sweden)

    Mengnan Liu

    2016-01-01

    Full Text Available In order to improve the electrical conversion efficiency of an electric tractor motor, a load torque based control strategy (LTCS is designed in this paper by using a particle swarm optimization algorithm (PSO. By mathematically modeling electric-mechanical performance and theoretical energy waste of the electric motor, as well as the transmission characteristics of the drivetrain, the objective function, control relationship, and analytical platform are established. Torque and rotation speed of the motor’s output shaft are defined as manipulated variables. LTCS searches the working points corresponding to the best energy conversion efficiency via PSO to control the running status of the electric motor and uses logic and fuzzy rules to fit the search initialization for load torque fluctuation. After using different plowing forces to imitate all the common tillage forces, the simulation of traction experiment is conducted, which proves that LTCS can make the tractor use electrical power efficiently and maintain agricultural applicability on farmland conditions. It provides a novel method of fabricating a more efficient electric motor used in the traction of an off-road vehicle.

  20. California customer load reductions during the electricity crisis: Did they help to keep the lights on?

    Energy Technology Data Exchange (ETDEWEB)

    Goldman, Charles A.; Barbose Galen L.; Eto, Joseph H.

    2002-05-01

    During summer 2001, Californians reduced electricity usage by 6 percent and average monthly peak demand by 8 percent, compared to summer 2000. These load reductions played an important role in avoiding the hundreds of hours of rotating power outages predicted several months prior. Many factors affected electricity use and peak demand in summer 2001, including weather, changes in the State's economy, and deliberate consumer responses to a variety of stimuli associated with the crisis. This paper assesses the roles played by these contributing factors, with a special focus on the extraordinary efforts made by Californians to reduce electricity consumption. We review the role of media coverage and informational campaigns on public awareness and the impact of rate increases and a variety of publicly funded programs in reducing electricity consumption. We also draw lessons for other regions that may be faced with the prospect of electricity shortages.

  1. Power Stabilization Strategy of Random Access Loads in Electric Vehicles Wireless Charging System at Traffic Lights

    Directory of Open Access Journals (Sweden)

    Linlin Tan

    2016-10-01

    Full Text Available An opportunity wireless charging system for electric vehicles when they stop and wait at traffic lights is proposed in this paper. In order to solve the serious power fluctuation caused by random access loads, this study presents a power stabilization strategy based on counting the number of electric vehicles in a designated area, including counting method, power source voltage adjustment strategy and choice of counting points. Firstly, the circuit model of a wireless power system with multi-loads is built and the equation of each load is obtained. Secondly, after the counting method of electric vehicles is stated, the voltage adjustment strategy, based on the number of electric vehicles when the system is at a steady state, is set out. Then, the counting points are chosen according to power curves when the voltage adjustment strategy is adopted. Finally, an experimental prototype is implemented to verify the power stabilization strategy. The experimental results show that, with the application of this strategy, the charging power is stabilized with the fluctuation of no more than 5% when loads access randomly.

  2. Computation of the radiation Q of dielectric-loaded electrically small antennas in integral equation formulations

    DEFF Research Database (Denmark)

    Kim, Oleksiy S.

    2016-01-01

    A new technique for estimating the impedance frequency bandwidth of electrically small antennas loaded with magneto-dielectric material from a single-frequency simulation in a surface integral equation solver is presented. The estimate is based on the inverse of the radiation Q computed using newly...

  3. A combined complex electrical impedance and acoustic emission study in limestone samples under uniaxial loading

    Science.gov (United States)

    Saltas, V.; Fitilis, I.; Vallianatos, F.

    2014-12-01

    In the present work, complex electrical impedance measurements in the frequency range of 10 mHz to 1 MHz were carried out in conjunction with acoustic emission monitoring in limestone samples subjected to linear and stepped-like uniaxial loading, up to ultimate failure. Cole-Cole plots of the complex impedance during the stepped loading of limestone have been used to discriminate the contributions of grains interior, grain boundaries and electrode polarization effects to the overall electrical behavior. The latter is well-described with an equivalent-circuit model which comprises components of constant phase elements and resistances in parallel connection. Electrical conductivity increases upon uniaxial loading giving rise to negative values of effective activation volume. This is a strong experimental evidence for the generation of transient electric signals recorded prior to seismic events and may be attributed to charge transfer (proton conduction) due to cracks generation and propagation as a result of the applied stress. The time-series of ac-conductivity at two distinct frequencies (10 kHz, 200 kHz) during linear loading of limestone samples exhibits a strong correlation with the acoustic emission activity obeying the same general self-similar law for critical phenomena that has been reported for the energy release before materials fracture.

  4. Analysis of relationships between hourly electricity price and load in deregulated real-time power markets

    Energy Technology Data Exchange (ETDEWEB)

    Lo, K.L.; Wu, Y.K. [University of Strathclyde, Glasgow (United Kingdom). Power Systems Research Group

    2004-07-01

    Risk management in the electric power industry involves measuring the risk for all instruments owned by a company. The value of many of these instruments depends directly on electricity prices. In theory, the wholesale price in a real-time market should reflect the short-run marginal cost. However, most markets are not perfectly competitive, therefore by understanding the degree of correlation between price and physical drivers, electric traders and consumers can manage their risk more effectively and efficiently. Market data from two power-pool architectures, both pre-2003 ISO-NE and Australia's NEM, have been studied. The dynamic character of electricity price is mean-reverting, and consists of intra-day and weekly variations, seasonal fluctuations, and instant jumps. Parts of them are affected by load demands. Hourly signals on both price and load are divided into deterministic and random components with a discrete Fourier transform algorithm. Next, the real-time price-load relationship for periodic and random signals is examined. In addition, time-varying volatility models are constructed on random price and random load with the GARCH model, and the correlation between them analysed. Volatility plays a critical role on evaluating option pricing and risk management. (author)

  5. Effect of blade flutter and electrical loading on small wind turbine noise

    Science.gov (United States)

    The effect of blade flutter and electrical loading on the noise level of two different size wind turbines was investigated at the Conservation and Production Research Laboratory (CPRL) near Bushland, TX. Noise and performance data were collected on two blade designs tested on a wind turbine rated a...

  6. Artificial neural network and SARIMA based models for power load forecasting in Turkish electricity market.

    Science.gov (United States)

    Bozkurt, Ömer Özgür; Biricik, Göksel; Tayşi, Ziya Cihan

    2017-01-01

    Load information plays an important role in deregulated electricity markets, since it is the primary factor to make critical decisions on production planning, day-to-day operations, unit commitment and economic dispatch. Being able to predict the load for a short term, which covers one hour to a few days, equips power generation facilities and traders with an advantage. With the deregulation of electricity markets, a variety of short term load forecasting models are developed. Deregulation in Turkish Electricity Market has started in 2001 and liberalization is still in progress with rules being effective in its predefined schedule. However, there is a very limited number of studies for Turkish Market. In this study, we introduce two different models for current Turkish Market using Seasonal Autoregressive Integrated Moving Average (SARIMA) and Artificial Neural Network (ANN) and present their comparative performances. Building models that cope with the dynamic nature of deregulated market and are able to run in real-time is the main contribution of this study. We also use our ANN based model to evaluate the effect of several factors, which are claimed to have effect on electrical load.

  7. Probabilistic Constrained Load Flow Considering Integration of Wind Power Generation and Electric Vehicles

    DEFF Research Database (Denmark)

    Vlachogiannis, Ioannis (John)

    2009-01-01

    A new formulation and solution of probabilistic constrained load flow (PCLF) problem suitable for modern power systems with wind power generation and electric vehicles (EV) demand or supply is represented. The developed stochastic model of EV demand/supply and the wind power generation model...

  8. Electricity demand load forecasting of the Hellenic power system using an ARMA model

    Energy Technology Data Exchange (ETDEWEB)

    Pappas, S.Sp. [ASPETE - School of Pedagogical and Technological Education Department of Electrical Engineering Educators N. Heraklion, 141 21 Athens (Greece); Ekonomou, L.; Chatzarakis, G.E.; Skafidas, P.D. [ASPETE-School of Pedagogical and Technological Education, Department of Electrical Engineering Educators, N. Heraklion, 141 21 Athens (Greece); Karampelas, P. [Hellenic American University, IT Department, 12 Kaplanon Str., 106 80 Athens (Greece); Karamousantas, D.C. [Technological Educational Institute of Kalamata, Antikalamos, 24 100 Kalamata (Greece); Katsikas, S.K. [University of Piraeus, Department of Technology Education and Digital Systems, 150 Androutsou St., 18 532 Piraeus (Greece)

    2010-03-15

    Effective modeling and forecasting requires the efficient use of the information contained in the available data so that essential data properties can be extracted and projected into the future. As far as electricity demand load forecasting is concerned time series analysis has the advantage of being statistically adaptive to data characteristics compared to econometric methods which quite often are subject to errors and uncertainties in model specification and knowledge of causal variables. This paper presents a new method for electricity demand load forecasting using the multi-model partitioning theory and compares its performance with three other well established time series analysis techniques namely Corrected Akaike Information Criterion (AICC), Akaike's Information Criterion (AIC) and Schwarz's Bayesian Information Criterion (BIC). The suitability of the proposed method is illustrated through an application to actual electricity demand load of the Hellenic power system, proving the reliability and the effectiveness of the method and making clear its usefulness in the studies that concern electricity consumption and electricity prices forecasts. (author)

  9. Fluctuation analysis of high frequency electric power load in the Czech Republic

    CERN Document Server

    Kracík, Jiří

    2016-01-01

    We analyze the electric power load in the Czech Republic (CR) which exhibits a seasonality as well as other oscillations typical for European countries. Moreover, we detect 1/f noise property of electrical power load with extra additional peaks that allows to separate it into a deterministic and stochastic part. We then focus on the analysis of the stochastic part using improved Multi-fractal Detrended Fluctuation Analysis method (MFDFA) to investigate power load datasets with a minute resolution. Extracting the noise part of the signal by using Fourier transform allows us to apply this method to obtain the fluctuation function and to estimate the generalized Hurst exponent together with the correlated Hurst exponent, its improvement for the non-Gaussian datasets. The results exhibit a strong presence of persistent behaviour and the dataset is characterized by a non-Gaussian skewed distribution. There are also indications for the presence of the probability distribution that has heavier tail than the Gaussian...

  10. Technical development of electric power storage system. Development of load conditioner

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, Toshikatsu

    1988-07-01

    The load conditioner heightens the utilization ratio of facilities by the stardardization of load for the suppliers and has the consumers advantageously utilize cheap electric power. The domestic facilities are basically composed of charging rectifier, discharging self-exciting inverter and secondary battery. As there presently exists lead battery as a secondary battery, the Electric Power Research Center developed a load conditioner system by using lead battery and is making its operational study. As a secondary lithium battery satisfying the compactness of further particular importance, there are high molecule battery using high molecule compounds such as polyaniline and polyacene, intercaration type battery using vanadium oxide or molybdenum disulfide, etc. Then, in order to materialize the enlargement and life lengthening of those batteries, the steady study of all of negative electrode, positive electrode, electrolyte, battery structure. (3 figs, 2 tabs)

  11. Modelling Load Shifing Using Electric Vehicles in a Smart Grid Environment

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-07-01

    Electric vehicles (EVs) represent both a new demand for electricity and a possible storage medium that could supply power to utilities. The 'load shifting' and 'vehicle-to-grid' concepts could help cut electricity demand during peak periods and prove especially helpful in smoothing variations in power generation introduced to the grid by variable renewable resources such as wind and solar power. This paper proposes a method for simulating the potential benefits of using EVs in load shifting and 'vehicle-to-grid' applications for four different regions -- the United States, Western Europe, China and Japan -- that are expected to have large numbers of EVs by 2050.

  12. Research of Charging(Discharging Orderly and Optimizing Load Curve for Electric Vehicles Based on Dynamic Electric Price and V2G

    Directory of Open Access Journals (Sweden)

    Yang Shuai

    2016-01-01

    Full Text Available Firstly, using the Monte Carlo method and simulation analysis, this paper builds models for the behaviour of electric vehicles, the conventional charging model and the fast charging model. Secondly, this paper studies the impact that the number of electric vehicles which get access to power grid has on the daily load curve. Then, the paper put forwards a dynamic pricing mechanism of electricity, and studies how this dynamic pricing mechanism guides the electric vehicles to charge orderly. Last but not the least, the paper presents a V2G mechanism. Under this mechanism, electric vehicles can charge orderly and take part in the peak shaving. Research finds that massive electric vehicles’ access to the power grid will increase the peak-valley difference of daily load curve. Dynamic pricing mechanism and V2G mechanism can effectively lead the electric vehicles to take part in peak-shaving, and optimize the daily load curve.

  13. California customer load reductions during the electricity crisis: Did they help to keep the lights on?

    Energy Technology Data Exchange (ETDEWEB)

    Goldman, Charles A.; Eto, Joseph H.; Barbose, Galen L.

    2002-05-01

    Recurring electricity shortages and rolling blackouts were widely forecasted for summer 2001 in California. Despite these predictions, blackouts were never ordered - in large part, due to the dramatic reductions in electricity use throughout the state. Compared to summer 2000, Californians reduced electricity usage by 6 percent and average monthly peak demand by 8 percent. Our analysis suggests that these reductions were not caused by either the weather or the downturn in the state's economy; rather, they were the result of extraordinary efforts by Californians to reduce electricity consumption. Based on the California Independent System Operator's (CAISO) available operating reserve margin during summer 2001, we estimate that the peak load reductions, which ranged between 3,200 and 5,600 MW in the four summer months, potentially avoided between 50 and 160 hours of rolling blackouts. This extraordinary response by Californians can be attributed to several factors including media coverage and informational campaigns that affected public awareness and understanding, real and/or perceived increases in electricity rates, and various policies and programs deployed by state policymakers and regulators to facilitate customer load reductions. Among these programs, we review the state's 20/20 rebate program, the utilities' energy efficiency programs, programs or initiatives implemented by the California Energy Commission and other state agencies, and load management and demand response programs offered by the state's investor-owned electric utilities and the CAISO. We estimate that energy efficiency and onsite generation projects that were initiated in 2001 will account for about 1,100 MW of customer load reductions, once all projects are installed. These savings represent about 25-30 percent of the observed load reductions and are likely to persist for many years. The persistence of the remaining savings, which were due to changes that customers

  14. RATIONAL MODES DETERMINATION OF TRACTION MOTORS LOADING-BACK FOR ELECTRIC ROLLING STOCK IN MAINLINE AND INDUSTRIAL TRANSPORT

    Directory of Open Access Journals (Sweden)

    A. M. Afanasov

    2014-05-01

    Full Text Available Purpose. Loading-back systems are used for post-maintenance acceptance tests of electric traction motors of electric rolling stock (ERS in mainline and industrial transport. The aim of the research is justification of choice method of the rational loading-back parameters of traction electric motors during the tests for heating. Methodology. At the heart of the choice method justification of the rational loading-back parameters is a theory of heating the homogeneous solid body and well-known methods of heating calculations of traction electric machines. Findings. Expediency of heating tests for electric traction motors at load currents equal to the starting current (for ERS of mainline transport or fifteen minutes current (for ERS of industrial transport was substantiated. It was shown that this increase of load current will reduce the electricity costs of the tests for 20–30% and shorten the tests duration for three–four times while ensuring the corrected power minimum of energy sources in loading-back system. Originality. It is shown that the energy costs for heating tests of the traction motors can be reduced by both the increasing the energy efficiency of the loading-back system and by the optimizing of loading mode of traction electric machines. Choice technique of rational modes of loading-back for electric traction motors of rolling stock in mainline and industrial transport was grounded. Practical value. Load current increase of traction electric motors during their tests for heating will reduce the total electricity consumption for the acceptance tests, reduce test time and total material costs for repair of the electric traction motors of rolling stock in mainline and industrial transport.

  15. Application of high-resolution domestic electricity load profiles in network modelling

    DEFF Research Database (Denmark)

    Marszal, Anna Joanna; Mendaza, Iker Diaz de Cerio; Heiselberg, Per Kvols

    2016-01-01

    % of buildings, the loading of the transformer and power lines is reduced in the summer time to 58% and 51%, respectively. However, the power lines are stress with bi-directional power flow. The results indicate that the business-as-usual approach to network modeling is not sufficient to capture......The ongoing development towards electrification of the energy consumption together with large deployment of renewable energy sources creates new challenges of variability and fluctuation of the electricity supply and increases complexity of the network operation. In order to capture all...... the particularities of electricity demand and on-site generation, e.g. the short-term spikes due use of high electricity consumption appliances such like electric kettle, and get a full picture of network performance, a high-resolution input data are needed. This paper compares the business-as-usual network modeling...

  16. Factor Analysis of the Aggregated Electric Vehicle Load Based on Data Mining

    Directory of Open Access Journals (Sweden)

    Yao Wang

    2012-06-01

    Full Text Available Electric vehicles (EVs and the related infrastructure are being developed rapidly. In order to evaluate the impact of factors on the aggregated EV load and to coordinate charging, a model is established to capture the relationship between the charging load and important factors based on data mining. The factors can be categorized as internal and external. The internal factors include the EV battery size, charging rate at different places, penetration of the charging infrastructure, and charging habits. The external factor is the time-of-use pricing (TOU policy. As a massive input data is necessary for data mining, an algorithm is implemented to generate a massive sample as input data which considers real-world travel patterns based on a historical travel dataset. With the input data, linear regression was used to build a linear model whose inputs were the internal factors. The impact of the internal factors on the EV load can be quantified by analyzing the sign, value, and temporal distribution of the model coefficients. The results showed that when no TOU policy is implemented, the rate of charging at home and range anxiety exerts the greatest influence on EV load. For the external factor, a support vector regression technique was used to build a relationship between the TOU policy and EV load. Then, an optimization model based on the relationship was proposed to devise a TOU policy that levels the load. The results suggest that implementing a TOU policy reduces the difference between the peak and valley loads remarkably.

  17. Climate Control Load Reduction Strategies for Electric Drive Vehicles in Cold Weather

    Energy Technology Data Exchange (ETDEWEB)

    Jeffers, Matthew A.; Chaney, Larry; Rugh, John P.

    2016-04-05

    When operated, the climate control system is the largest auxiliary load on a vehicle. This load has significant impact on fuel economy for conventional and hybrid vehicles, and it drastically reduces the driving range of all electric vehicles (EVs). Heating is even more detrimental to EV range than cooling because no engine waste heat is available. Reducing the thermal loads on the heating, ventilating, and air conditioning system will extend driving range and increase the market penetration of EVs. Researchers at the National Renewable Energy Laboratory have evaluated strategies for vehicle climate control load reduction with special attention toward grid connected electric vehicles. Outdoor vehicle thermal testing and computational modeling were used to assess potential strategies for improved thermal management and to evaluate the effectiveness of thermal load reduction technologies. A human physiology model was also used to evaluate the impact on occupant thermal comfort. Experimental evaluations of zonal heating strategies demonstrated a 5.5% to 28.5% reduction in cabin heating energy over a 20-minute warm-up. Vehicle simulations over various drive cycles show a 6.9% to 18.7% improvement in EV range over baseline heating using the most promising zonal heating strategy investigated. A national-level analysis was conducted to determine the overall national impact. If all vehicles used the best zonal strategy, the range would be improved by 7.1% over the baseline heating range. This is a 33% reduction in the range penalty for heating.

  18. Mutual Information-Based Inputs Selection for Electric Load Time Series Forecasting

    Directory of Open Access Journals (Sweden)

    Nenad Floranović

    2013-02-01

    Full Text Available Providing accurate load forecast to electric utility corporations is essential in order to reduce their operational costs and increase profits. Hence, training set selection is an important preprocessing step which has to be considered in practice in order to increase the accuracy of load forecasts. The usage of mutual information (MI has been recently proposed in regression tasks, mostly for feature selection and for identifying the real instances from training sets that contains noise and outliers. This paper proposes a methodology for the training set selection in a least squares support vector machines (LS-SVMs load forecasting model. A new application of the concept of MI is presented for the selection of a training set based on MI computation between initial training set instances and testing set instances. Accordingly, several LS-SVMs models have been trained, based on the proposed methodology, for hourly prediction of electric load for one day ahead. The results obtained from a real-world data set indicate that the proposed method increases the accuracy of load forecasting as well as reduces the size of the initial training set needed for model training.

  19. Climate Control Load Reduction Strategies for Electric Drive Vehicles in Cold Weather: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Jeffers, Matthew; Chaney, Lawrence; Rugh, John

    2016-03-31

    When operated, the climate control system is the largest auxiliary load on a vehicle. This load has significant impact on fuel economy for conventional and hybrid vehicles, and it drastically reduces the driving range of all electric vehicles (EVs). Heating is even more detrimental to EV range than cooling because no engine waste heat is available. Reducing the thermal loads on the heating, ventilating, and air conditioning system will extend driving range and increase the market penetration of EVs. Researchers at the National Renewable Energy Laboratory have evaluated strategies for vehicle climate control load reduction with special attention toward grid connected electric vehicles. Outdoor vehicle thermal testing and computational modeling were used to assess potential strategies for improved thermal management and to evaluate the effectiveness of thermal load reduction technologies. A human physiology model was also used to evaluate the impact on occupant thermal comfort. Experimental evaluations of zonal heating strategies demonstrated a 5.5% to 28.5% reduction in cabin heating energy over a 20-minute warm-up. Vehicle simulations over various drive cycles show a 6.9% to 18.7% improvement in EV range over baseline heating using the most promising zonal heating strategy investigated. A national-level analysis was conducted to determine the overall national impact. If all vehicles used the best zonal strategy, the range would be improved by 7.1% over the baseline heating range. This is a 33% reduction in the range penalty for heating.

  20. An experimentally validated contactless acoustic energy transfer model with resistive-reactive electrical loading

    Science.gov (United States)

    Shahab, S.; Gray, M.; Erturk, A.

    2015-04-01

    This paper investigates analytical modeling and experimental validation of Ultrasonic Acoustic Energy Transfer (UAET) for low-power electricity transfer to exploit in wireless applications ranging from medical implants to underwater sensor systems. A piezoelectric receiver bar is excited by incident acoustic waves originating from a source of known strength located at a specific distance from the receiver. The receiver is a free-free piezoelectric cylinder operating in the 33- mode of piezoelectricity with a fundamental resonance frequency above the audible frequency range. In order to extract the electrical power output, the piezoelectric receiver bar is shunted to a generalized resistive-reactive circuit. The goal is to quantify the electrical power delivered to the load (connected to the receiver) in terms of the source strength. Experimental validations are presented along with parameter optimization studies. Sensitivity of the electrical power output to the excitation frequency in the neighborhood of the receiver's underwater resonance frequency, source-to-receiver distance, and source-strength level are reported. Resistive and resistive-reactive electrical loading cases are discussed for performance enhancement and frequency-wise robustness. Simulations and experiments reveal that the presented multiphysics analytical model for UAET can be used to predict the coupled system dynamics with very good accuracy.

  1. Static deflection analysis of non prismatic multilayer p-NEMS cantilevers under electrical load

    Energy Technology Data Exchange (ETDEWEB)

    Pavithra, M., E-mail: pavithramasi78@gmail.com [PhD Research Scholar, Department of Electronics and Instrumentation, Bharathiar University, Coimbatore-46 (India); Muruganand, S. [Assistant professor, Department of Electronics and Instrumentation, Bharathiar University, Coimbatore-46 (India)

    2016-04-13

    Deflection of Euler-Bernoulli non prismatic multilayer piezoelectric nano electromechanical (p-NEMS) cantilever beams have been studied theoretically for various profiles of p-NEMS cantilevers by applying the electrical load. This problem has been answered by applying the boundary conditions derived by simple polynomials. This method is applied for various profiles like rectangular and trapezoidal by varying the thickness of the piezoelectric layer as well as the material. The obtained results provide the better deflection for trapezoidal profile with ZnO piezo electric layer of suitable nano cantilevers for nano scale applications.

  2. Reliability Analysis of Piezoelectric Truss Structures Under Joint Action of Electric and Mechanical Loading

    Institute of Scientific and Technical Information of China (English)

    YANG Duo-he; AN Wei-guang; ZHU Rong-rong; MIAO Han

    2006-01-01

    Based on the finite element method(FEM) for the dynamical analysis of piezoelectric truss structures, the expressions of safety margins of strength fracture and damage electric field in the structure element are given considering electromechanical coupling effect under the joint action of electric and mechanical load. By importing the stochastic FEM,reliability of piezoelectric truss structures is analyzed by solving for partial derivative in the process of solving dynamical response of structure system with mode-superposition method. The influence of electromechanical coupling effect to reliability index is then analyzed through an example.

  3. Research on Propeller Dynamic Load Simulation System of Electric Propulsion Ship

    Institute of Scientific and Technical Information of China (English)

    HUANG Hui; SHEN Ai-di; CHU Jian-xin

    2013-01-01

    A dynamic marine propeller simulation system was developed,which is utilized for meeting the experimental requirement of theory research and engineering design of marine electric propulsion system.By applying an actual ship parameter and its accurate propeller J'~KT' and J'~Kp' curve data,functional experiments based on the simulation system were carried out.The experiment results showed that the system can correctly emulate the propeller characteristics,produce the dynamic and steady performances of the propeller under different navigation modes,and present actual load torque for electric propulsion motor.

  4. Evaluation of antagonist coactivation strategies elicited from electrically stimulated muscles under load-moving conditions.

    Science.gov (United States)

    Zhou, B H; Katz, S R; Baratta, R V; Solomonow, M; D'Ambrosia, R D

    1997-07-01

    Muscle coactivation strategies that produce ankle dorsiflexion and plantar flexion were elicited by electrical stimulation of the tibialis anterior (TA) and soleus (SOL) muscles of the cat, and examined under several loading conditions. Four different load types were used: free-limb motion (no load), fly-wheel, and two pendulums, each with a different lever arm. Three types of coactivation strategies were considered. The first coactivation strategy consisted of antagonist activity that decreased as the agonist activity increased. The second strategy consisted of increasing antagonist activity with increasing agonist activity. And, in the third strategy, antagonist coactivation decreased at low force levels, then increased at high force levels. The three strategies were evaluated based on the joint angle's peak-to-peak movement and its ability to track a linear input command given by the correlation coefficient of the output signal versus linear input. Results showed that increasing antagonist activity resulted in decreasing peak-to-peak angle and a decreased signal tracking capability for each load condition. The latter, however, was not as obvious in the flywheel load (as compared with free-moving and pendulum conditions). A decreasing peak-to-peak torque for pendulum loads was also observed with increasing antagonist activity. In all loading conditions, maximal peak-to-peak angle and torque were present when a moderate degree of antagonist activity was engaged, and signal tracking capability improved with earlier engagement of the antagonist muscles. It is suggested that strategies using a combination of low-level coactivation, as described in the physiological literature and previous functional electrical stimulation (FES) studies, could satisfactorily address the issues of controllability and efficiency while maintaining long-term joint integrity.

  5. Electrical resistance load effect on magnetoelectric coupling of magnetostrictive/piezoelectric laminated composite

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yaojin, E-mail: wangyaojin@hotmail.co [Key Laboratory of Inorganic Functional Material and Device, Shanghai Institute of Ceramics, Chinese Academy of Sciences, 215 Chengbei Road, Jiading, Shanghai 201800 (China); Graduate University of the Chinese Academy of Sciences, Beijing 100049 (China); Zhao, Xiangyong [Key Laboratory of Inorganic Functional Material and Device, Shanghai Institute of Ceramics, Chinese Academy of Sciences, 215 Chengbei Road, Jiading, Shanghai 201800 (China); Jiao, Jie; Liu, Linhua [Key Laboratory of Inorganic Functional Material and Device, Shanghai Institute of Ceramics, Chinese Academy of Sciences, 215 Chengbei Road, Jiading, Shanghai 201800 (China); Graduate University of the Chinese Academy of Sciences, Beijing 100049 (China); Di, Wenning; Luo, Haosu [Key Laboratory of Inorganic Functional Material and Device, Shanghai Institute of Ceramics, Chinese Academy of Sciences, 215 Chengbei Road, Jiading, Shanghai 201800 (China); Or, Siu Wing, E-mail: eeswor@polyu.edu.h [Department of Electrical Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon (Hong Kong)

    2010-06-25

    The effect of electrical resistance load on the magnetoelectric (ME) coupling of laminated composite of Tb{sub 0.3}Dy{sub 0.7}Fe{sub 1.92} (Terfenol-D) magnetostrictive alloy and 0.7Pb (Mg{sub 1/3}Nb{sub 2/3})O{sub 3}-0.3PbTiO{sub 3} (PMN-PT) piezoelectric single crystal is investigated at both non-resonance and resonance frequencies. The results show that (i) the ME coefficient and ME resonance frequency increase with the increase in electrical resistance load, and (ii) the maximum ME power occurs in open-circuit condition. The present study provides the basis for the design of ME sensors and their signal-processing and electronic circuits.

  6. Condition Assessment and End-of-Life Prediction System for Electric Machines and Their Loads

    Science.gov (United States)

    Parlos, Alexander G.; Toliyat, Hamid A.

    2005-01-01

    An end-of-life prediction system developed for electric machines and their loads could be used in integrated vehicle health monitoring at NASA and in other government agencies. This system will provide on-line, real-time condition assessment and end-of-life prediction of electric machines (e.g., motors, generators) and/or their loads of mechanically coupled machinery (e.g., pumps, fans, compressors, turbines, conveyor belts, magnetic levitation trains, and others). In long-duration space flight, the ability to predict the lifetime of machinery could spell the difference between mission success or failure. Therefore, the system described here may be of inestimable value to the U.S. space program. The system will provide continuous monitoring for on-line condition assessment and end-of-life prediction as opposed to the current off-line diagnoses.

  7. Advanced Intelligent System Application to Load Forecasting and Control for Hybrid Electric Bus

    Science.gov (United States)

    Momoh, James; Chattopadhyay, Deb; Elfayoumy, Mahmoud

    1996-01-01

    The primary motivation for this research emanates from providing a decision support system to the electric bus operators in the municipal and urban localities which will guide the operators to maintain an optimal compromise among the noise level, pollution level, fuel usage etc. This study is backed up by our previous studies on study of battery characteristics, permanent magnet DC motor studies and electric traction motor size studies completed in the first year. The operator of the Hybrid Electric Car must determine optimal power management schedule to meet a given load demand for different weather and road conditions. The decision support system for the bus operator comprises three sub-tasks viz. forecast of the electrical load for the route to be traversed divided into specified time periods (few minutes); deriving an optimal 'plan' or 'preschedule' based on the load forecast for the entire time-horizon (i.e., for all time periods) ahead of time; and finally employing corrective control action to monitor and modify the optimal plan in real-time. A fully connected artificial neural network (ANN) model is developed for forecasting the kW requirement for hybrid electric bus based on inputs like climatic conditions, passenger load, road inclination, etc. The ANN model is trained using back-propagation algorithm employing improved optimization techniques like projected Lagrangian technique. The pre-scheduler is based on a Goal-Programming (GP) optimization model with noise, pollution and fuel usage as the three objectives. GP has the capability of analyzing the trade-off among the conflicting objectives and arriving at the optimal activity levels, e.g., throttle settings. The corrective control action or the third sub-task is formulated as an optimal control model with inputs from the real-time data base as well as the GP model to minimize the error (or deviation) from the optimal plan. These three activities linked with the ANN forecaster proving the output to the

  8. Analysis of the blasting effect on the electric shove loading efficiency of the open pit

    Institute of Scientific and Technical Information of China (English)

    FU Tian-guang; SUN Ying

    2008-01-01

    The connection between blasting cost and comprehensive cost is the main concern. Some blasting effect factors (such as unit explosive consumption, uniformity of blockness, shape and porosity of blasting heap), which had an influence on electric shove loading efficiency, were analyzed. In the end a project to properly increase in blasting cost to decrease the comprehensive cost was put forward. At the same time, the hole-by-hole blasting is effective technology to improve blasting effect.

  9. Development of an Internet of Things based Electricity Load Management System

    Directory of Open Access Journals (Sweden)

    Dr. D. O. Dike

    2016-08-01

    Full Text Available Continuous overload to a power system is a problem as it reduces the life span of the generators. Load management is very vital in optimizing the performance of generating plants by properly managing the generated energy. During peak demand times, the energy used by consumers are expensive compared to that used during off peak demand time; this is because utility companies need to engage bigger generators and other infrastructures in order to supply the demanded energy. To prevent the need for the procurement of bigger generators and other infrastructures needed to augment electrical power needed by consumers during peak demand time, an Internet of Things (IoT based Electricity Load Management System is developed in this paper. The Arduino mega 2560 board and the Arduino WiFi Shield 101 are used in the controller and connectivity elements respectively, ACS712 module is employed in the sensory block to measure current; in order to determine the power being used by loads while Solid State Relays are used for actuation purposes. The entire blocks were integrated to form a functional system whose mode of operation is based on IoT technology that can be employed for effective management electrical energy.

  10. Dynamic additional loads influencing the fatigue life of gears in an electric vehicle transmission

    Directory of Open Access Journals (Sweden)

    G.Belingardi

    2014-10-01

    Full Text Available In recent years the implementation of the electric engine in the automotive industries has been increasingly marked. The speed of the electric motors is much higher than the combustion engine ones, bringing transmission gears to be subjected to high dynamic loads. For this reason the dynamic effects on fatigue life of these components have be taken into account in a more careful way respect to what is done with the usual gears. In the present work the overload effects due to both speed and meshing in a gear couple of an electric vehicle transmission have been analyzed. The electric vehicle is designed for urban people mobility and presents all the requirements to be certified as M1 vehicle (a weight less than 600 kg and a maximum speed more than 90 Km/h. To investigate the overload effects of teeth in contact, the reference gear design Standards (ISO 6336 introduce a specific multiplicative factor to the applied load called Internal Dynamic Factor (Kv. Aim of this work is to evaluate how dynamic overloads may influence the fatigue life of the above quoted gears in term of durability. To this goal, Kv values have been calculated by means of the analytical equations (ISO 6336 Methods B and C and then they have been compared with the results coming from multibody simulations, involving full rigid and rigid-flexible models.

  11. Thermal Energy Storage for Building Load Management: Application to Electrically Heated Floor

    Directory of Open Access Journals (Sweden)

    Hélène Thieblemont

    2016-07-01

    Full Text Available In cold climates, electrical power demand for space conditioning becomes a critical issue for utility companies during certain periods of the day. Shifting a portion or all of it to off-peak periods can help reduce peak demand and reduce stress on the electrical grid. Sensible thermal energy storage (TES systems, and particularly electrically heated floors (EHF, can store thermal energy in buildings during the off-peak periods and release it during the peak periods while maintaining occupants’ thermal comfort. However, choosing the type of storage system and/or its configuration may be difficult. In this paper, the performance of an EHF for load management is studied. First, a methodology is developed to integrate EHF in TRNSYS program in order to investigate the impact of floor assembly on the EHF performance. Then, the thermal comfort (TC of the night-running EHF is studied. Finally, indicators are defined, allowing the comparison of different EHF. Results show that an EHF is able to shift 84% of building loads to the night while maintaining acceptable TC in cold climate. Moreover, this system is able to provide savings for the customer and supplier if there is a significant difference between off-peak and peak period electricity prices.

  12. Comparison and Analysis of Magnetic-Geared Permanent Magnet Electrical Machine at No-Load

    Directory of Open Access Journals (Sweden)

    Liu Xiping

    2014-12-01

    Full Text Available Magnetic-geared permanent magnet (MGPM electrical machine is a new type of machine by incorporating magnetic gear into PM electrical machine, and it may be in operation with low-speed, high-torque and direct-driven. In this paper, three types of MGPM machines are present, and a quantitative comparison among them is performed by finite element analysis (FEA. The magnetic field distribution, stable torque and back EMF are obtained at no-load. The results show that three types of MGPM machine are suitable for different application fields respectively according to their own advantages, such as high torque and back EMF, which form an important foundation for MGPM electrical machine research.

  13. Advances in electric power and energy systems load and price forecasting

    CERN Document Server

    2017-01-01

    A comprehensive review of state-of-the-art approaches to power systems forecasting from the most respected names in the field, internationally. Advances in Electric Power and Energy Systems is the first book devoted exclusively to a subject of increasing urgency to power systems planning and operations. Written for practicing engineers, researchers, and post-grads concerned with power systems planning and forecasting, this book brings together contributions from many of the world’s foremost names in the field who address a range of critical issues, from forecasting power system load to power system pricing to post-storm service restoration times, river flow forecasting, and more. In a time of ever-increasing energy demands, mounting concerns over the environmental impacts of power generation, and the emergence of new, smart-grid technologies, electricity price forecasting has assumed a prominent role within both the academic and industrial ar nas. Short-run forecasting of electricity prices has become nece...

  14. Effect of Enhanced Air Temperature (extreme heat, and Load of Non-Linear Against the Use of Electric Power

    Directory of Open Access Journals (Sweden)

    I Ketut Wijaya

    2015-12-01

    Full Text Available Usage Electric power is very easy to do, because the infrastructure for connecting  already available and widely sold. Consumption electric power is not accompanied by the ability to recognize electric power. The average increase of electricity power in Bali in extreme weather reaches 10% in years 2014, so that Bali suffered power shortages and PLN as the manager of electric power to perform scheduling on of electric power usage. Scheduling is done because many people use electric power as the load  of fan and Air Conditioner exceeding the previous time. Load of fan, air conditioning, and computers including non-linear loads which can add heat on the conductor of electricity. Non-linear load and hot weather can lead to heat on conductor so  insulation damaged  and cause electrical short circuit. Data of electric power obtained through questionnaires, surveys, measurement and retrieve data from various parties. Fires that occurred in 2014, namely 109 events, 44 is  event caused by an electric short circuit (approximately 40%. Decrease power factors can cause losses of electricity and hot. Heat can cause and adds heat on the  conductor electric. The analysis showed  understanding electric power of the average  is 27,700 with value between 20 to 40. So an understanding of the electrical power away from the understand so that many errors because of the act own. Installation tool ELCB very necessary but very necessary provide counseling   of electricity to the community.

  15. The Combined Effect of Electrical Stimulation and High-Load Isometric Contraction on Protein Degradation Pathways in Muscle Atrophy Induced by Hindlimb Unloading

    OpenAIRE

    Naoto Fujita; Shinichiro Murakami; Hidemi Fujino

    2011-01-01

    High-load isometric exercise is considered an effective countermeasure against muscle atrophy, but therapeutic electrical stimulation for muscle atrophy is often performed without loading. In the present study, we investigated the combined effectiveness of electrical stimulation and high-load isometric contraction in preventing muscle atrophy induced by hindlimb unloading. Electrical stimulation without loading resulted in slight attenuation of muscle atrophy. Moreover, combining electrical s...

  16. Towards smart energy systems: application of kernel machine regression for medium term electricity load forecasting.

    Science.gov (United States)

    Alamaniotis, Miltiadis; Bargiotas, Dimitrios; Tsoukalas, Lefteri H

    2016-01-01

    Integration of energy systems with information technologies has facilitated the realization of smart energy systems that utilize information to optimize system operation. To that end, crucial in optimizing energy system operation is the accurate, ahead-of-time forecasting of load demand. In particular, load forecasting allows planning of system expansion, and decision making for enhancing system safety and reliability. In this paper, the application of two types of kernel machines for medium term load forecasting (MTLF) is presented and their performance is recorded based on a set of historical electricity load demand data. The two kernel machine models and more specifically Gaussian process regression (GPR) and relevance vector regression (RVR) are utilized for making predictions over future load demand. Both models, i.e., GPR and RVR, are equipped with a Gaussian kernel and are tested on daily predictions for a 30-day-ahead horizon taken from the New England Area. Furthermore, their performance is compared to the ARMA(2,2) model with respect to mean average percentage error and squared correlation coefficient. Results demonstrate the superiority of RVR over the other forecasting models in performing MTLF.

  17. New approaches to provide ride-through for critical loads in electric power distribution systems

    Science.gov (United States)

    Montero-Hernandez, Oscar C.

    2001-07-01

    The extensive use of electronic circuits has enabled modernization, automation, miniaturization, high quality, low cost, and other achievements regarding electric loads in the last decades. However, modern electronic circuits and systems are extremely sensitive to disturbances from the electric power supply. In fact, the rate at which these disturbances happen is considerable as has been documented in recent years. In response to the power quality concerns presented previously, this dissertation is proposing new approaches to provide ride-through for critical loads during voltage disturbances with emphasis on voltage sags. In this dissertation, a new approach based on an AC-DC-AC system is proposed to provide ride-through for critical loads connected in buildings and/or an industrial system. In this approach, a three-phase IGBT inverter with a built in Dc-link voltage regulator is suitably controlled along with static by-pass switches to provide continuous power to critical loads. During a disturbance, the input utility source is disconnected and the power from the inverter is connected to the load. The remaining voltage in the AC supply is converted to DC and compensated before being applied to the inverter and the load. After detecting normal utility conditions, power from the utility is restored to the critical load. In order to achieve an extended ride-through capability a second approach is introduced. In this case, the Dc-link voltage regulator is performed by a DC-DC Buck-Boost converter. This new approach has the capability to mitigate voltage variations below and above the nominal value. In the third approach presented in this dissertation, a three-phase AC to AC boost converter is investigated. This converter provides a boosting action for the utility input voltages, right before they are applied to the load. The proposed Pulse Width Modulation (PWM) control strategy ensures independent control of each phase and compensates for both single-phase or poly

  18. Fluctuation analysis of high frequency electric power load in the Czech Republic

    Science.gov (United States)

    Kracík, Jiří; Lavička, Hynek

    2016-11-01

    We analyze the electric power load in the Czech Republic (CR) which exhibits a seasonality as well as other oscillations typical for European countries. Moreover, we detect the 1/f noise property of electrical power load with extra additional peaks that allows to separate it into a deterministic and stochastic part. We then focus on the analysis of the stochastic part using improved Multi-fractal Detrended Fluctuation Analysis method (MFDFA) to investigate power load datasets with a minute resolution. Extracting the noise part of the signal by using Fourier transform allows us to apply this method to obtain the fluctuation function and to estimate the generalized Hurst exponent together with the correlated Hurst exponent, its improvement for the non-Gaussian datasets. The results exhibit a strong presence of persistent behavior or strong anti-persistent behavior for the differences and the dataset is characterized by a non-Gaussian skewed distribution. There are also indications for the presence of the probability distribution that has heavier tail than the Gaussian distribution.

  19. An Electrical Energy Consumer Load Monitoring and Control System Through SMS Based

    Directory of Open Access Journals (Sweden)

    J. Tsado

    2012-05-01

    Full Text Available This study presents an SMS based Consumer Load Monitoring and Control System (CLMCS incorporating the widely used GSM network to facilitate the communication of electrical energy consumption by the user to his mobile phone. Its operation is centered on an AT89C52 microcontroller programmed in assembly language. A dedicated GSM modem with a SIM card is interfaced to the ports of the microcontroller through a PNP transistor (BC557 and a Normally Closed (NC relay to send SMS notification alert to user’s mobile phone when power supply is restored to his premises and whenever the energy consumed exceeds the maximum value set by the end user in this case 1 kW. This enables the consumer to respond promptly by cutting off power supply to his load unit when not needed. With this, a great deal of energy is saved and the consumer enjoys maximum satisfaction of the electrical energy paid for; hence an improvement, stability and utilization of electrical energy are achievable.

  20. Monitoring and Characterization of Miscellaneous Electrical Loads in a Large Retail Environment

    Energy Technology Data Exchange (ETDEWEB)

    Gentile-Polese, L.; Frank, S.; Sheppy, M.; Lobato, C.; Rader, E.; Smith, J.; Long, N.

    2014-02-01

    Buildings account for 40% of primary energy consumption in the United States (residential 22%; commercial 18%). Most (70% residential and 79% commercial) is used as electricity. Thus, almost 30% of U.S. primary energy is used to provide electricity to buildings. Plug loads play an increasingly critical role in reducing energy use in new buildings (because of their increased efficiency requirements), and in existing buildings (as a significant energy savings opportunity). If all installed commercial building miscellaneous electrical loads (CMELs) were replaced with energy-efficient equipment, a potential annual energy saving of 175 TWh, or 35% of the 504 TWh annual energy use devoted to MELs, could be achieved. This energy saving is equivalent to the annual energy production of 14 average-sized nuclear power plants. To meet DOE's long-term goals of reducing commercial building energy use and carbon emissions, the energy efficiency community must better understand the components and drivers of CMEL energy use, and develop effective reduction strategies. These goals can be facilitated through improved data collection and monitoring methodologies, and evaluation of CMELs energy-saving techniques.

  1. Determining the Interruptible Load with Strategic Behavior in a Competitive Electricity Market

    Directory of Open Access Journals (Sweden)

    Tae Hyun Yoo

    2014-12-01

    Full Text Available In a deregulated market, independent system operators meet power balance based on supply and demand bids to maximize social welfare. Since electricity markets are typically oligopolies, players with market power may withhold capacity to maximize profit. Such exercise of market power can lead to various problems, including increased electricity prices, and hence lower social welfare. Here we propose an approach to maximize social welfare and prevent the exercising of market power by means of interruptible loads in a competitive market environment. Our approach enables management of the market power by analyzing the benefit to the companies of capacity withdrawal and scheduling resources with interruptible loads. Our formulation shows that we can prevent power companies and demand-resource owners from exercising market powers. The oligopolistic conditions are described using the Cournot model to reflect the capacity withdrawal in electricity markets. The numerical results confirm the effectiveness of proposed method, via a comparison of perfect competition and oligopoly scenarios. Our approach provides reductions in market-clearing prices, increases in social welfare, and more equal distribution of surpluses between players.

  2. Distributed smart device for monitoring, control and management of electric loads in domotic environments.

    Science.gov (United States)

    Morales, Ricardo; Badesa, Francisco J; García-Aracil, Nicolas; Perez-Vidal, Carlos; Sabater, Jose María

    2012-01-01

    This paper presents a microdevice for monitoring, control and management of electric loads at home. The key idea is to compact the electronic design as much as possible in order to install it inside a Schuko socket. Moreover, the electronic Schuko socket (electronic microdevice + Schuko socket) has the feature of communicating with a central unit and with other microdevices over the existing powerlines. Using the existing power lines, the proposed device can be installed in new buildings or in old ones. The main use of this device is to monitor, control and manage electric loads to save energy and prevent accidents produced by different kind of devices (e.g., iron) used in domestic tasks. The developed smart device is based on a single phase multifunction energy meter manufactured by Analog Devices (ADE7753) to measure the consumption of electrical energy and then to transmit it using a serial interface. To provide current measurement information to the ADE7753, an ultra flat SMD open loop integrated circuit current transducer based on the Hall effect principle manufactured by Lem (FHS-40P/SP600) has been used. Moreover, each smart device has a PL-3120 smart transceiver manufactured by LonWorks to execute the user's program, to communicate with the ADE7753 via serial interface and to transmit information to the central unit via powerline communication. Experimental results show the exactitude of the measurements made using the developed smart device.

  3. Electricity demand loads modeling using AutoRegressive Moving Average (ARMA) models

    Energy Technology Data Exchange (ETDEWEB)

    Pappas, S.S. [Department of Information and Communication Systems Engineering, University of the Aegean, Karlovassi, 83 200 Samos (Greece); Ekonomou, L.; Chatzarakis, G.E. [Department of Electrical Engineering Educators, ASPETE - School of Pedagogical and Technological Education, N. Heraklion, 141 21 Athens (Greece); Karamousantas, D.C. [Technological Educational Institute of Kalamata, Antikalamos, 24100 Kalamata (Greece); Katsikas, S.K. [Department of Technology Education and Digital Systems, University of Piraeus, 150 Androutsou Srt., 18 532 Piraeus (Greece); Liatsis, P. [Division of Electrical Electronic and Information Engineering, School of Engineering and Mathematical Sciences, Information and Biomedical Engineering Centre, City University, Northampton Square, London EC1V 0HB (United Kingdom)

    2008-09-15

    This study addresses the problem of modeling the electricity demand loads in Greece. The provided actual load data is deseasonilized and an AutoRegressive Moving Average (ARMA) model is fitted on the data off-line, using the Akaike Corrected Information Criterion (AICC). The developed model fits the data in a successful manner. Difficulties occur when the provided data includes noise or errors and also when an on-line/adaptive modeling is required. In both cases and under the assumption that the provided data can be represented by an ARMA model, simultaneous order and parameter estimation of ARMA models under the presence of noise are performed. The produced results indicate that the proposed method, which is based on the multi-model partitioning theory, tackles successfully the studied problem. For validation purposes the produced results are compared with three other established order selection criteria, namely AICC, Akaike's Information Criterion (AIC) and Schwarz's Bayesian Information Criterion (BIC). The developed model could be useful in the studies that concern electricity consumption and electricity prices forecasts. (author)

  4. Internalizing carbon costs in electricity markets. Using certificates in a load-based emissions trading scheme

    Energy Technology Data Exchange (ETDEWEB)

    Gillenwater, Michael [Science, Technology and Environmental Policy Program, Woodrow Wilson School of Public and International Affairs, Robertson Hall, Princeton University, Princeton, NJ 08540 (United States); Breidenich, Clare [Independent consultant, Seattle, WA (United States)

    2009-01-15

    Several western states have considered developing a regulatory approach to reduce greenhouse gas (GHG) emissions from the electric power industry, referred to as a load-based (LB) cap-and-trade scheme. A LB approach differs from the traditional source-based (SB) cap-and-trade approach in that the emission reduction obligation is placed upon Load Serving Entities (LSEs), rather than electric generators. The LB approach can potentially reduce the problem of emissions leakage, relative to a SB system. For any of these proposed LB schemes to be effective, they must be compatible with modern, and increasingly competitive, wholesale electricity markets. LSE's are unlikely to know the emissions associated with their power purchases. Therefore, a key challenge for a LB scheme is how to assign emissions to each LSE. This paper discusses the problems with one model for assigning emissions under a LB scheme and proposes an alternative, using unbundled Generation Emission Attribute Certificates. By providing a mechanism to internalize an emissions price signal at the generator dispatch level, the tradable certificate model addresses both these problems and provides incentives identical to a SB scheme. (author)

  5. Internalizing carbon costs in electricity markets: Using certificates in a load-based emissions trading scheme

    Energy Technology Data Exchange (ETDEWEB)

    Gillenwater, Michael [Science, Technology and Environmental Policy Program, Woodrow Wilson School of Public and International Affairs, Robertson Hall, Princeton University, Princeton, NJ 08540 (United States)], E-mail: gillenwater@alum.mit.edu; Breidenich, Clare [Independent consultant, Seattle, WA (United States)], E-mail: cbreidenich@yahoo.com

    2009-01-15

    Several western states have considered developing a regulatory approach to reduce greenhouse gas (GHG) emissions from the electric power industry, referred to as a load-based (LB) cap-and-trade scheme. A LB approach differs from the traditional source-based (SB) cap-and-trade approach in that the emission reduction obligation is placed upon Load Serving Entities (LSEs), rather than electric generators. The LB approach can potentially reduce the problem of emissions leakage, relative to a SB system. For any of these proposed LB schemes to be effective, they must be compatible with modern, and increasingly competitive, wholesale electricity markets. LSE's are unlikely to know the emissions associated with their power purchases. Therefore, a key challenge for a LB scheme is how to assign emissions to each LSE. This paper discusses the problems with one model for assigning emissions under a LB scheme and proposes an alternative, using unbundled Generation Emission Attribute Certificates. By providing a mechanism to internalize an emissions price signal at the generator dispatch level, the tradable certificate model addresses both these problems and provides incentives identical to a SB scheme.

  6. Distributed Smart Device for Monitoring, Control and Management of Electric Loads in Domotic Environments

    Directory of Open Access Journals (Sweden)

    Carlos Perez-Vidal

    2012-04-01

    Full Text Available This paper presents a microdevice for monitoring, control and management of electric loads at home. The key idea is to compact the electronic design as much as possible in order to install it inside a Schuko socket. Moreover, the electronic Schuko socket (electronic microdevice + Schuko socket has the feature of communicating with a central unit and with other microdevices over the existing powerlines. Using the existing power lines, the proposed device can be installed in new buildings or in old ones. The main use of this device is to monitor, control and manage electric loads to save energy and prevent accidents produced by different kind of devices (e.g., iron used in domestic tasks. The developed smart device is based on a single phase multifunction energy meter manufactured by Analog Devices (ADE7753 to measure the consumption of electrical energy and thento transmit it using a serial interface. To provide current measurement information to the ADE7753, an ultra flat SMD open loop integrated circuit current transducer based on the Hall effect principle manufactured by Lem (FHS-40P/SP600 has been used. Moreover, each smart device has a PL-3120 smart transceiver manufactured by LonWorks to execute the user’s program, to communicate with the ADE7753 via serial interface and to transmit information to the central unit via powerline communication. Experimental results show the exactitude of the measurements made using the developed smart device.

  7. Investigation of Control Algorithms for Tracked Vehicle Mobility Load Emulation for a Combat Hybrid Electric Power System

    Science.gov (United States)

    2009-07-30

    Investigation of Control Algorithms for Tracked Vehicle Mobility Load Emulation for a Combat Hybrid Electric Power System Jarrett Goodell and...TITLE AND SUBTITLE Investigation of Control Algorithms for Tracked Vehicle Mobility Load Emulation for a Combat Hybrid Electric Power System 5a...for ~ 22 ton tracked vehicle • Tested and Developed: – Motors, Generators, Batteries, Inverters, DC-DC Converters , Thermal Management, Pulse Power

  8. Utilization of Electric Vehicles and Their Used Batteries for Peak-Load Shifting

    Directory of Open Access Journals (Sweden)

    Muhammad Aziz

    2015-04-01

    Full Text Available The utilization of electric vehicles (EV and their used batteries in supporting small-scale energy management systems were studied. Both theoretical study and practical demonstration were performed to measure the feasibility of the developed system. Each five EVs and used EV batteries were used along with 20 kW photovoltaic (PV panels as a renewable energy source. The main objective of the developed system is performing a peak-load shifting by utilizing EVs, used EV batteries and PV panels. The planning of load leveling was performed 24 h ahead for each 30 min period. The studies showed that the application of EVs and used EV batteries in supporting certain small-scale energy management systems is feasible. In addition, some findings during the demonstration test were listed and analyzed for the purpose of further system development and deployment.

  9. Crack density and electrical resistance in indium-tin-oxide/polymer thin films under cyclic loading

    KAUST Repository

    Mora Cordova, Angel

    2014-11-01

    Here, we propose a damage model that describes the degradation of the material properties of indium-tin-oxide (ITO) thin films deposited on polymer substrates under cyclic loading. We base this model on our earlier tensile test model and show that the new model is suitable for cyclic loading. After calibration with experimental data, we are able to capture the stress-strain behavior and changes in electrical resistance of ITO thin films. We are also able to predict the crack density using calibrations from our previous model. Finally, we demonstrate the capabilities of our model based on simulations using material properties reported in the literature. Our model is implemented in the commercially available finite element software ABAQUS using a user subroutine UMAT.[Figure not available: see fulltext.].

  10. Matlab for Forecasting of Electric Power Load Based on BP Neural Network

    Science.gov (United States)

    Wang, Xi-Ping; Shi, Ming-Xi

    Modeling and predicting electricity consumption play a vital role both in developed and developing countries for policy makers and related organizations. Improve load forecasting technology level is not only beneficial to plan power management and make reasonable construction plan, but also good for saving energy and reducing power cost, and then, it can improve the economic benefits and social benefit for power system. BP neural network is one of the most widely used neural networks and it has many advantages in the power load forecasting. Matlab has become the best technology application software which has been internationally recognized, the software has many characteristics, such as data visualization function and neural network toolbox, for these, it is the essential software when we do some research on neural network.

  11. Ultrabroadband Microwave Metamaterial Absorber Based on Electric SRR Loaded with Lumped Resistors

    Science.gov (United States)

    Zhao, Jingcheng; Cheng, Yongzhi

    2016-10-01

    An ultrabroadband microwave metamaterial absorber (MMA) based on an electric split-ring resonator (ESRR) loaded with lumped resistors is presented. Compared with an ESRR MMA, the composite MMA (CMMA) loaded with lumped resistors offers stronger absorption over an extremely extended bandwidth. The reflectance simulated under different substrate loss conditions indicates that incident electromagnetic (EM) wave energy is mainly consumed by the lumped resistors. The simulated surface current and power loss density distributions further illustrate the mechanism underlying the observed absorption. Further simulation results indicate that the performance of the CMMA can be tuned by adjusting structural parameters of the ESRR and lumped resistor parameters. We fabricated and measured MMA and CMMA samples. The CMMA yielded below -10 dB reflectance from 4.4 GHz to 18 GHz experimentally, with absorption bandwidth and relative bandwidth of 13.6 GHz and 121.4%, respectively. This ultrabroadband microwave absorber has potential applications in the electromagnetic energy harvesting and stealth fields.

  12. Short-Term Electrical Load Forecasting using Neuro-Fuzzy Models

    Energy Technology Data Exchange (ETDEWEB)

    Park, Young Jin; Shim, Hyun Jeong; Wang, Bo Hyeun [Kang Nung National University (Korea)

    2000-03-01

    This paper proposes a systematic method to develop short-term electrical load forecasting systems using neuro-fuzzy models, The primary goal of the proposed method is to improve the performance of the prediction model in terms of accuracy and reliability. For this, the proposed method explores the advantages of the structure learning of the neuro-fuzzy model. The proposed load forecasting system first builds an initial structure off-line for each hour of four day types and then stores the resultant initial structures in the initial structure bank. Whenever a prediction needs to be made, the proposed system initializes the neuro-fuzzy model with the appropriate initial structure stored and trains the initialized model. In order to demonstrate the viability of the proposed method, we develop an one hour ahead load forecasting system by using the real load data collected during 1993 and 1994 at KEPCO. Simulation results reveal that the prediction system developed in this paper can achieve a remarkable improvement on both accuracy and reliability compared with the prediction systems based on multilayer perceptions, radial basis function networks, and neuro-fuzzy models without the structure learning. (author). 23 refs., 11 figs., 8 tabs.

  13. Effects of interruptible load program on equilibrium outcomes of electricity markets with wind power

    Energy Technology Data Exchange (ETDEWEB)

    An, Xuena; Zhang, Shaohua; Li, Xue [Shanghai Univ. (China). Key Lab. of Power Station Automation Technology

    2013-07-01

    High wind power penetration presents a lot of challenges to the flexibility and reliability of power system operation. In this environment, various demand response (DR) programs have got much attention. As an effective measure of demand response programs, interruptible load (IL) programs have been widely used in electricity markets. This paper addresses the problem of impacts of the IL programs on the equilibrium outcomes of electricity wholesale markets with wind power. A Cournot equilibrium model of wholesale markets with wind power is presented, in which IL programs is included by a market demand model. The introduction of the IL programs leads to a non-smooth equilibrium problem. To solve this equilibrium problem, a novel solution method is proposed. Numerical examples show that IL programs can lower market price and its volatility significantly, facilitate the integration of wind power.

  14. Analysis of electrical circuits with variable load regime parameters projective geometry method

    CERN Document Server

    Penin, A

    2015-01-01

    This book introduces electric circuits with variable loads and voltage regulators. It allows to define invariant relationships for various parameters of regime and circuit sections and to prove the concepts characterizing these circuits. Generalized equivalent circuits are introduced. Projective geometry is used for the interpretation of changes of operating regime parameters. Expressions of normalized regime parameters and their changes are presented. Convenient formulas for the calculation of currents are given. Parallel voltage sources and the cascade connection of multi-port networks are d

  15. Analysis of the blasting effect on the electric shove loading efficiency of the open pit

    Institute of Scientific and Technical Information of China (English)

    FU Tian-guang; SUN Ying

    2008-01-01

    The connection between blasting cost and comprehensive cost is the main concern.Some blasting effect factors (such as unit explosive consumption,uniformity of blockness,shape and porosity of blasting heap),which had an influence on electric shove loading efficiency,were analyzed.In the end a project to properly increase in blasting cost to decrease the comprehensive cost was put forward.At the same time,the hole-by-hole blasting is effective technology to improve blasting effect.

  16. AN EXPLORATORY ANALYSIS ON HALF-HOURLY ELECTRICITY LOAD PATTERNS LEADING TO HIGHER PERFORMANCES IN NEU

    Directory of Open Access Journals (Sweden)

    K.A.D. Deshani

    2014-05-01

    Full Text Available Accurate prediction of electricity demand can bring extensive benefits to any country as the forecasted values help the relevant authorities to take decisions regarding electricity generation, transmission and distribution appropriately. The literature reveals that, when compared to conventional time series techniques, the improved artificial intelligent approaches provide better prediction accuracies. However, the accuracy of predictions using intelligent approaches like neural networks are strongly influenced by the correct selection of inputs and the number of neuro-forecasters used for prediction. Deshani, Hansen, Attygalle, & Karunarathne (2014 suggested that a cluster analysis could be performed to group similar day types, which contribute towards selecting a better set of neuro-forecasters in neural networks. The cluster analysis was based on the daily total electricity demands as their target was to predict the daily total demands using neural networks. However, predicting half-hourly demand seems more appropriate due to the considerable changes of electricity demand observed during a particular day. As such clusters are identified considering half-hourly data within the daily load distribution curves. Thus, this paper is an improvement to Deshani et. al. (2014, which illustrates how the half hourly demand distribution within a day, is incorporated when selecting the inputs for the neuro-forecasters.

  17. Real-Time Vehicle Energy Management System Based on Optimized Distribution of Electrical Load Power

    Directory of Open Access Journals (Sweden)

    Yuefei Wang

    2016-10-01

    Full Text Available As a result of severe environmental pressure and stringent government regulations, refined energy management for vehicles has become inevitable. To improve vehicle fuel economy, this paper presents a bus-based energy management system for the electrical system of internal combustion engine vehicles. Both the model of an intelligent alternator and the model of a lead-acid battery are discussed. According to these models, the energy management for a vehicular electrical system is formulated as a global optimal control problem which aims to minimize fuel consumption. Pontryagin’s minimum principle is applied to solve the optimal control problem to realize a real-time control strategy for electrical energy management in vehicles. The control strategy can change the output of the intelligent alternator and the battery with the changes of electrical load and driving conditions in real-time. Experimental results demonstrate that, compared to the traditional open-loop control strategy, the proposed control strategy for vehicle energy management can effectively reduce fuel consumption and the fuel consumption per 100 km is decreased by approximately 1.7%.

  18. Forecasting Peak Load Electricity Demand Using Statistics and Rule Based Approach

    Directory of Open Access Journals (Sweden)

    Z. Ismail

    2009-01-01

    Full Text Available Problem statement: Forecasting of electricity load demand is an essential activity and an important function in power system planning and development. It is a prerequisite to power system expansion planning as the world of electricity is dominated by substantial lead times between decision making and its implementation. The importance of demand forecasting needs to be emphasized at all level as the consequences of under or over forecasting the demand are serious and will affect all stakeholders in the electricity supply industry. Approach: If under estimated, the result is serious since plant installation cannot easily be advanced, this will affect the economy, business, loss of time and image. If over estimated, the financial penalty for excess capacity (i.e., over-estimated and wasting of resources. Therefore this study aimed to develop new forecasting model for forecasting electricity load demand which will minimize the error of forecasting. In this study, we explored the development of rule-based method for forecasting electricity peak load demand. The rule-based system synergized human reasoning style of fuzzy systems through the use of set of rules consisting of IF-THEN approximators with the learning and connectionist structure. Prior to the implementation of rule-based models, SARIMAT model and Regression time series were used. Results: Modification of the basic regression model and modeled it using Box-Jenkins auto regressive error had produced a satisfactory and adequate model with 2.41% forecasting error. With rule-based based forecasting, one can apply forecaster expertise and domain knowledge that is appropriate to the conditions of time series. Conclusion: This study showed a significant improvement in forecast accuracy when compared with the traditional time series model. Good domain knowledge of the experts had contributed to the increase in forecast accuracy. In general, the improvement will depend on the conditions of the data

  19. Analysis of the reactive power consumption and the harmonics in the network by the non-linear electrical loads

    Energy Technology Data Exchange (ETDEWEB)

    Cogo, Joao Roberto [Escola Federal de Engenharia de Itajuba, MG (Brazil)

    1994-12-31

    The non linear electrical loads can give rise to a number of disturbances in electrical power networks. Among them, the high consumption of relative power is to be noted and so is the several harmonic components which may be injected in the industry system and very often in the utility system. So, by using appropriate technical considerations, as well as measurements in typical special electrical loads, such negative effects are analyzed and ways of minimizing them are suggested. (author) 3 refs., 11 figs., 6 tabs.

  20. Real-Time Load-Side Control of Electric Power Systems

    Science.gov (United States)

    Zhao, Changhong

    Two trends are emerging from modern electric power systems: the growth of renewable (e.g., solar and wind) generation, and the integration of information technologies and advanced power electronics. The former introduces large, rapid, and random fluctuations in power supply, demand, frequency, and voltage, which become a major challenge for real-time operation of power systems. The latter creates a tremendous number of controllable intelligent endpoints such as smart buildings and appliances, electric vehicles, energy storage devices, and power electronic devices that can sense, compute, communicate, and actuate. Most of these endpoints are distributed on the load side of power systems, in contrast to traditional control resources such as centralized bulk generators. This thesis focuses on controlling power systems in real time, using these load side resources. Specifically, it studies two problems. (1) Distributed load-side frequency control: We establish a mathematical framework to design distributed frequency control algorithms for flexible electric loads. In this framework, we formulate a category of optimization problems, called optimal load control (OLC), to incorporate the goals of frequency control, such as balancing power supply and demand, restoring frequency to its nominal value, restoring inter-area power flows, etc., in a way that minimizes total disutility for the loads to participate in frequency control by deviating from their nominal power usage. By exploiting distributed algorithms to solve OLC and analyzing convergence of these algorithms, we design distributed load-side controllers and prove stability of closed-loop power systems governed by these controllers. This general framework is adapted and applied to different types of power systems described by different models, or to achieve different levels of control goals under different operation scenarios. We first consider a dynamically coherent power system which can be equivalently modeled with

  1. Investigation of load leveling in Hokuriku Electric Power Co., Inc.; Hokuriku denryoku no fuka heijunka eno torikumi

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-08-01

    Hokuriku Electric Power Co., Inc. aims at an around 2% improvement of the load factor up to 2005, by which the quick and proper service and the proposal of load leveling menu are planned. This paper describes an outline of the investigation of load leveling. Various programs have been proposed so that the customers can further shift the load by their consideration. Proposed systems include the time-of-day electricity rate system, the load regulation contract system for industries, the seasonal time-of-day rate system, the electric power system for snowmelt in which the load is dumped at the peak, and the secondary electric power system for snowmelt. Accompanying with the revision of electric utility law, the enlargement of its available time, the price reduction, and the discount rate system for the ice regenerative air conditioners have been provided. For the business activities, a demonstration model house was exhibited to indicate a proper house with local characteristics in Hokuriku district. Furthermore, the spreading activities of regenerative systems and the consulting activities have been positively promoted. 4 figs., 1 tab.

  2. We Need to Talk... Developing Communicating Power Supplies to Monitor & Control Miscellaneous Electric Loads

    Energy Technology Data Exchange (ETDEWEB)

    Weber, Andrew; Lanzisera, Steven; Liao, Anna; Meier, Alan

    2014-08-11

    Plug loads represent 30percent of total electricity use in residential buildings. Significant energy savings would result from an accurate understanding of which miscellaneous electric devices are using energy, at what time, and in what quantity. Commercially available plug load monitoring and control solutions replace or limit the attached device's native controls - forcing the user to adapt to a separate set of controls associated with the monitoring and control hardware. A better solution is integration of these capabilities at the power supply level. In this paper, we demonstrate a method achieving this integration. Our solution allows unobtrusive power monitoring and control while retaining native device control features. Further, our prototype enables intelligent behaviors by allowing devices to respond to the state of one another automatically. The CPS enables energy savings while demonstrating an added level of functionality to the user. If CPS technology became widespread in devices, a combination of automated and human interactive solutions would enable high levels of energy savings in buildings.

  3. Optimizing the structure of metal load in order to reduce electricity consumption in the production of steel

    Science.gov (United States)

    Pǎcurar, Cristina; Hepuť, Teodor; Ardelean, Marius

    2016-06-01

    As the basic units in the preparation of steel, in industrial practice is used oxygen converters and electric arc furnaces. In research carried out has been taken into account structure analysis load electric arc furnaces of the specific consumption of electricity (kWh/t). Data to be achieved for a number of 96 batches, have been taken into account load holding metal of each assortment of scrap metal, these varieties being considered as independent parameters, and electricity consumption is considered dependent parameter. By processing the data in the EXCEL spreadsheet programs and MATLAB have been obtained correlations between parameters analyze, analytical results being presented and the graph. On the basis of an analysis of these correlations to choose optimal structure of the load in order to obtain an acceptable energy consumption from technical and economic point of view.

  4. ANALYSIS OF ENERGY EFFICIENCY OF OPERATING MODES OF ELECTRICAL SYSTEMS WITH THE TRACTION LOADS

    Directory of Open Access Journals (Sweden)

    V. E. Bondarenko

    2017-03-01

    Full Text Available Innovative scenarios of reliable energy supply of transportation process aimed at reducing the specific energy consumption and increase energy efficiency of the systems of electric traction. The paper suggests innovative energy saving directions in traction networks of railways and new circuit solutions accessing traction substations in energy systems networks, ensure energy security of the transportation process. To ensure the energy security of rail transport special schemes were developed to propose the concept of external power traction substations, which would increase the number of connections to the networks of 220 – 330 kV, as well as the creation of transport and energy corridors, development of its own supply of electric networks of 110 kV substations and mobile RP-110 kV of next generation. Therefore, the investment program of the structures owned by the Ukrainian Railways (Ukrzaliznytsia need to be synchronized in their technological characteristics, as well as the criteria of reliability and quality of power supply with the same external energy investment programs. It is found that without any load on left or right supplying arm one of two less loaded phases of traction transformer begins generating specific modes in the supplying three-phase line. Thus, modes of mobile substation cause leakage in one of the phases of the supply line of traction transformers of active-capacitive current, and as a result generating energy in the main power line of 154 kV, which is fixed and calculated by electricity meters. For these three phase mode supply network is necessary to use 1st algorithm, i.e. taking into account the amount of electricity as the energy in all phases. For effective application of reactive power compensation devices in the AC traction power supply systems it is proposed to develop regulatory documentation on necessity of application and the order of choice of parameters and placement of compensation systems taking into

  5. Short-Term Forecasting of Electric Loads Using Nonlinear Autoregressive Artificial Neural Networks with Exogenous Vector Inputs

    Directory of Open Access Journals (Sweden)

    Jaime Buitrago

    2017-01-01

    Full Text Available Short-term load forecasting is crucial for the operations planning of an electrical grid. Forecasting the next 24 h of electrical load in a grid allows operators to plan and optimize their resources. The purpose of this study is to develop a more accurate short-term load forecasting method utilizing non-linear autoregressive artificial neural networks (ANN with exogenous multi-variable input (NARX. The proposed implementation of the network is new: the neural network is trained in open-loop using actual load and weather data, and then, the network is placed in closed-loop to generate a forecast using the predicted load as the feedback input. Unlike the existing short-term load forecasting methods using ANNs, the proposed method uses its own output as the input in order to improve the accuracy, thus effectively implementing a feedback loop for the load, making it less dependent on external data. Using the proposed framework, mean absolute percent errors in the forecast in the order of 1% have been achieved, which is a 30% improvement on the average error using feedforward ANNs, ARMAX and state space methods, which can result in large savings by avoiding commissioning of unnecessary power plants. The New England electrical load data are used to train and validate the forecast prediction.

  6. Development of an Energy-Savings Calculation Methodology for Residential Miscellaneous Electric Loads: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Hendron, R.; Eastment, M.

    2006-08-01

    In order to meet whole-house energy savings targets beyond 50% in residential buildings, it will be essential that new technologies and systems approaches be developed to address miscellaneous electric loads (MELs). These MELs are comprised of the small and diverse collection of energy-consuming devices found in homes, including what are commonly known as plug loads (televisions, stereos, microwaves), along with all hard-wired loads that do not fit into other major end-use categories (doorbells, security systems, garage door openers). MELs present special challenges because their purchase and operation are largely under the control of the occupants. If no steps are taken to address MELs, they can constitute 40-50% of the remaining source energy use in homes that achieve 60-70% whole-house energy savings, and this percentage is likely to increase in the future as home electronics become even more sophisticated and their use becomes more widespread. Building America (BA), a U.S. Department of Energy research program that targets 50% energy savings by 2015 and 90% savings by 2025, has begun to identify and develop advanced solutions that can reduce MELs.

  7. Application of high-resolution domestic electricity load profiles in network modelling

    DEFF Research Database (Denmark)

    Marszal, Anna Joanna; Mendaza, Iker Diaz de Cerio; Heiselberg, Per Kvols

    2016-01-01

    The ongoing development towards electrification of the energy consumption together with large deployment of renewable energy sources creates new challenges of variability and fluctuation of the electricity supply and increases complexity of the network operation. In order to capture all the parti......The ongoing development towards electrification of the energy consumption together with large deployment of renewable energy sources creates new challenges of variability and fluctuation of the electricity supply and increases complexity of the network operation. In order to capture all......-minute resolution. The load profiles of the household appliances are created using a bottom-up model, which uses the 1-minute cycle power use characteristics of a single appliance as the main building block. The profiles of heavy electric appliances, such as heat pump, are not included in the above......-mentioned model, as they are closely related to the thermal properties of a building. Therefore, two type of single family houses equipped with heat pump are simulated in EnergyPlus with 1-minute time step. The PV generation profile is obtained from a model developed in Matlab environment. In the second part...

  8. Load leveling efforts of The Hokkaido Electric Power Co. Inc.; Hokkaido Denryoku no fuka heijunka eno torikumi ni tsuite

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-04-01

    The Hokkaido Electric Power Co., Inc., aiming to enhance power generation efficiency through power load levelling, strives to expand and substantiate its electricity billing menu and to popularize and encourage the use of levelling-oriented apparatuses and systems most of which are designed for utilizing midnight power. The billing menu has in it a snow-melting power which is cut off for load levelling during the peak demand time zone. For domestic use, a time zone-specified lighting system named Dream Eight is created, which is one of the billing systems dependent upon time zone. Introduced therein for industrial use is a demand/supply adjustment contract system. Furthermore, in compliance with the amended Electricity Business Law that came into force in 1995, efforts are under way for revising the period wherein power is to be supplied for melting snow, expanding the scope of application of the power supply system dependent upon time zone, and newly introducing a heat accumulation assisted peak adjustment contract system and an operation adjustment contract system. As for business efforts in relation to load levelling, the company proposes household electrical systems centering about 200V high-efficiency apparatuses, electric water warmer contributing to the enhancement of year-round load levelling, popularization and reinforcement of electric snow melting systems, and power utilizing technologies capable of meeting local demands raised for example by agriculture and fishery.

  9. Training Load Monitoring Algorithms on Highly Sub-Metered Home Electricity Consumption Data

    Institute of Scientific and Technical Information of China (English)

    Mario Berges; Ethan Goldman; H. Scott Matthews; Lucio Soibelman

    2008-01-01

    The growing interest in energy-efficient buildings is driving changes in investment, design, and occupant behavior. To better focus cost and resource conservation efforts, electricity consumption feedback can be used to provide motivation, guidance, and verification. Disaggregating by end-use helps both con-sumers and producers to identify targets for conservation. While hardware-based sub-metering is costly and labor-intensive, non-intrusive load monitoring (NILM) is capable of gathering detailed energy-use data with minimal equipment cost and installation time. However, variations in measurements between metering de-vices complicate the process of compiling the necessary appliance profiles. Future work involves the devel-opment of NILM algorithms using sensor fusion and detailed appliance-level data gathered from a highly-sensed house currently being constructed near Pittsburgh, Pennsylvania.

  10. The influence of the structure of the metal load removal from liquid steel in electric arc furnaces

    Science.gov (United States)

    Pǎcurar, Cristina; Hepuť, Teodor; Crisan, Eugen

    2016-06-01

    One of the main technical and economic indicators in the steel industry and steel respectively the development it is the removal of liquid steel. This indicator depends on several factors, namely technology: the structure and the quality metal load, the degree of preparedness of it, and the content of non-metallic material accompanying the unit of drawing up, the technology for the elaboration, etc. research has been taken into account in drawing up steel electric arc furnace type spring EBT (Electric Bottom taping), seeking to load and removing components of liquid steel. Metal load has been composed of eight metal grades, in some cases with great differences in terms of quality. Data obtained were processed in the EXCEL spreadsheet programs and MATLAB, the results obtained being presented both graphically and analytically. On the basis of the results obtained may opt for a load optimal structure metal.

  11. Impact of optimal load response to real-time electricity price on power system constraints in Denmark

    DEFF Research Database (Denmark)

    Hu, Weihao; Chen, Zhe; Bak-Jensen, Birgitte

    2010-01-01

    and may represent the future of electricity markets in some ways, is chosen as the studied power system in this paper. A distribution system where wind power capacity is 126% of maximum loads is chosen as the study case. This paper presents a nonlinear load optimization method to real-time power price...... for demand side management in order to save the energy costs as much as possible. Simulation results show that the optimal load response to a real-time electricity price has some good impacts on power system constraints in a distribution system with high wind power penetrations....... for demand side management generates different load profiles and may have some impacts on power system constraints, such as voltage limits and capacity limits. The western Danish power system, which is currently the grid area in the world that has the largest share of wind power in its generation profiles...

  12. Hydrogen-or-Fossil-Combustion Nuclear Combined-Cycle Systems for Base- and Peak-Load Electricity Production

    Energy Technology Data Exchange (ETDEWEB)

    Forsberg, Charles W [ORNL; Conklin, Jim [ORNL

    2007-09-01

    A combined-cycle power plant is described that uses (1) heat from a high-temperature nuclear reactor to meet base-load electrical demands and (2) heat from the same high-temperature reactor and burning natural gas, jet fuel, or hydrogen to meet peak-load electrical demands. For base-load electricity production, fresh air is compressed; then flows through a heat exchanger, where it is heated to between 700 and 900 C by heat provided by a high-temperature nuclear reactor via an intermediate heat-transport loop; and finally exits through a high-temperature gas turbine to produce electricity. The hot exhaust from the Brayton-cycle gas turbine is then fed to a heat recovery steam generator that provides steam to a steam turbine for added electrical power production. To meet peak electricity demand, the air is first compressed and then heated with the heat from a high-temperature reactor. Natural gas, jet fuel, or hydrogen is then injected into the hot air in a combustion chamber, combusts, and heats the air to 1300 C-the operating conditions for a standard natural-gas-fired combined-cycle plant. The hot gas then flows through a gas turbine and a heat recovery steam generator before being sent to the exhaust stack. The higher temperatures increase the plant efficiency and power output. If hydrogen is used, it can be produced at night using energy from the nuclear reactor and stored until needed. With hydrogen serving as the auxiliary fuel for peak power production, the electricity output to the electric grid can vary from zero (i.e., when hydrogen is being produced) to the maximum peak power while the nuclear reactor operates at constant load. Because nuclear heat raises air temperatures above the auto-ignition temperatures of the various fuels and powers the air compressor, the power output can be varied rapidly (compared with the capabilities of fossil-fired turbines) to meet spinning reserve requirements and stabilize the electric grid. This combined cycle uses the

  13. Regulation of unbalanced electromagnetic moment in mutual loading systems of electric machines of traction rolling stock and multiple unit of mainline and industrial transport

    Directory of Open Access Journals (Sweden)

    A. M. Afanasov

    2014-12-01

    Full Text Available Purpose. The research data are aimed to identify the regulatory principles of unbalanced electromagnetic moment of mutually loaded electric machines of traction rolling stock and multiple unit of main and industrial transport. The purpose of this study is energy efficiency increase of the testing of traction electric machines of direct and pulse current using the improvement methods of their mutual loading, including the principles of automatic regulation of mutual loading system. Methodology. The general theoretical provisions and principles of system approach to the theoretical electric engineering, the theory of electric machines and theoretical mechanics are the methodological basis of this research. The known methods of analysis of electromagnetic and electromechanical processes in electrical machines of direct and pulse current are used in the study. Methods analysis of loading modes regulation of traction electric machines was conducted using the generalized scheme of mutual loading. It is universal for all known methods to cover the losses of idling using the electric power. Findings. The general management principles of mutual loading modes of the traction electric machines of direct and pulse current by regulating their unbalanced electric magnetic moment were developed. Regulatory options of unbalanced electromagnetic moment are examined by changing the difference of the magnetic fluxes of mutually loaded electric machines, the current difference of electric machines anchors, the difference of the angular velocities of electric machines shafts. Originality. It was obtained the scientific basis development to improve the energy efficiency test methods of traction electric machines of direct and pulse current. The management principles of mutual loading modes of traction electric machines were formulated. For the first time it is introduced the concept and developed the principles of regulation of unbalanced electromagnetic moment in

  14. A New Neural Network Approach to Short Term Load Forecasting of Electrical Power Systems

    Directory of Open Access Journals (Sweden)

    Farshid Keynia

    2011-03-01

    Full Text Available Short-term load forecast (STLF is an important operational function in both regulated power systems and deregulated open electricity markets. However, STLF is not easy to handle due to the nonlinear and random-like behaviors of system loads, weather conditions, and social and economic environment variations. Despite the research work performed in the area, more accurate and robust STLF methods are still needed due to the importance and complexity of STLF. In this paper, a new neural network approach for STLF is proposed. The proposed neural network has a novel learning algorithm based on a new modified harmony search technique. This learning algorithm can widely search the solution space in various directions, and it can also avoid the overfitting problem, trapping in local minima and dead bands. Based on this learning algorithm, the suggested neural network can efficiently extract the input/output mapping function of the forecast process leading to high STLF accuracy. The proposed approach is tested on two practical power systems and the results obtained are compared with the results of several other recently published STLF methods. These comparisons confirm the validity of the developed approach.

  15. An electrical load measurements dataset of United Kingdom households from a two-year longitudinal study

    Science.gov (United States)

    Murray, David; Stankovic, Lina; Stankovic, Vladimir

    2017-01-01

    Smart meter roll-outs provide easy access to granular meter measurements, enabling advanced energy services, ranging from demand response measures, tailored energy feedback and smart home/building automation. To design such services, train and validate models, access to data that resembles what is expected of smart meters, collected in a real-world setting, is necessary. The REFIT electrical load measurements dataset described in this paper includes whole house aggregate loads and nine individual appliance measurements at 8-second intervals per house, collected continuously over a period of two years from 20 houses. During monitoring, the occupants were conducting their usual routines. At the time of publishing, the dataset has the largest number of houses monitored in the United Kingdom at less than 1-minute intervals over a period greater than one year. The dataset comprises 1,194,958,790 readings, that represent over 250,000 monitored appliance uses. The data is accessible in an easy-to-use comma-separated format, is time-stamped and cleaned to remove invalid measurements, correctly label appliance data and fill in small gaps of missing data.

  16. Muscle electrical activity during exercises with and without load executed on dry land and in an aquatic environment

    Directory of Open Access Journals (Sweden)

    Indira Nayra Paz Santos

    Full Text Available Introduction Muscle activity in the aquatic environment was investigated using electromyographic analyses. The physical properties of water and the resistance used may influence the response of the muscle during exercise. The objective of this study was to evaluate the electrical activity in water and on the floor during flexion and knee extension exercises with and without load and aimed at understanding the muscular response while performing resistance exercises in water. Methods The sample consisted of 14 volunteers between 18 and 35 years old who were subjected to active exercises involving knee flexion and extension with and without load on the floor and in water. Electromyography was performed during the movement. Results A significant increase was found in the electrical activity of the rectus femoris muscle during exercises on the floor. The biceps femoris muscle showed increased electromyographic activity when resistance was used. A significant increase was found in the electrical activity of the rectus femoris muscle compared with exercises with and without load and the moment of rest in immersion. The electrical activity of the rectus and biceps femoris muscles was reduced in exercises with load and without load in a therapy pool compared with on the floor. Conclusion There was a reduction of the electromyographic activity in the aquatic environment compared with that on the ground, which could be attributed to the effects from hot water. Therefore, it is believed that resistance exercises can be performed early in a therapy pool, which will facilitate the prevention and treatment of musculoskeletal disorders.

  17. 1993 Pacific Northwest Loads and Resources Study, Pacific Northwest Economic and Electricity Use Forecast. Technical Appendix: Volume 1.

    Energy Technology Data Exchange (ETDEWEB)

    None

    1994-02-01

    This publication documents the load forecast scenarios and assumptions used to prepare BPA's Whitebook. It is divided into: intoduction, summary of 1993 Whitebook electricity demand forecast, conservation in the load forecast, projection of medium case electricity sales and underlying drivers, residential sector forecast, commercial sector forecast, industrial sector forecast, non-DSI industrial forecast, direct service industry forecast, and irrigation forecast. Four appendices are included: long-term forecasts, LTOUT forecast, rates and fuel price forecasts, and forecast ranges-calculations.

  18. Field data collection of miscellaneous electrical loads in Northern California: Initial results

    Energy Technology Data Exchange (ETDEWEB)

    Greenblatt, Jeffery B. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Environmental Energy Technologies Division. Energy Analysis and Environmental Impacts Dept.; Pratt, Stacy [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Environmental Energy Technologies Division. Energy Analysis and Environmental Impacts Dept.; Willem, Henry [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Environmental Energy Technologies Division. Energy Analysis and Environmental Impacts Dept.; Claybaugh, Erin [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Environmental Energy Technologies Division. Energy Analysis and Environmental Impacts Dept.; Desroches, Louis-Benoit [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Environmental Energy Technologies Division. Energy Analysis and Environmental Impacts Dept.; Beraki, Bereket [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Environmental Energy Technologies Division. Energy Analysis and Environmental Impacts Dept.; Nagaraju, Mythri [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Environmental Energy Technologies Division. Energy Analysis and Environmental Impacts Dept.; Price, Sarah K. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Environmental Energy Technologies Division. Energy Analysis and Environmental Impacts Dept.; Young, Scott J. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Environmental Energy Technologies Division. Energy Analysis and Environmental Impacts Dept.

    2013-02-25

    This report describes efforts to measure energy use of miscellaneous electrical loads (MELs) in 880 San Francisco Bay Area homes during the summer of 2012. Ten regions were selected for metering: Antioch, Berkeley, Fremont, Livermore, Marin County (San Rafael, Novato, Fairfax, and Mill Valley), Oakland/Emeryville, Pleasanton, Richmond, San Leandro, and Union City. The project focused on three major categories of devices: entertainment (game consoles, set-top boxes, televisions and video players), home office (computers, monitors and network equipment), and kitchen plug-loads (coffee/espresso makers, microwave ovens/toaster ovens/toasters, rice/slow cookers and wine chillers). These categories were important to meter because they either dominated the estimated overall energy use of MELs, are rapidly changing, or there are very little energy consumption data published. A total of 1,176 energy meters and 143 other sensors were deployed, and 90% of these meters and sensors were retrieved. After data cleaning, we obtained 711 valid device energy use measurements, which were used to estimate, for a number of device subcategories, the average time spent in high power, low power and “off” modes, the average energy use in each mode, and the average overall energy use. Consistent with observations made in previous studies, we find on average that information technology (IT) devices (home entertainment and home office equipment) consume more energy (15.0 and 13.0 W, respectively) than non-IT devices (kitchen plug-loads; 4.9 W). Opportunities for energy savings were identified in almost every device category, based on the time spent in various modes and/or the power levels consumed in those modes. Future reports will analyze the collected data in detail by device category and compare results to those obtained from prior studies.

  19. Electric Heating Property from Butyl Rubber-Loaded Boron Carbide Composites

    Institute of Scientific and Technical Information of China (English)

    MENG Dechuan; WANG Ninghui; LI Guofeng

    2014-01-01

    We researched the electric heating property from butyl rubber-loaded boron carbide composite. The effects of boron carbide content on bulk resistivity, voltage-current characteristic, thermal conductivity and thermal stability of boron carbide/butyl rubber (IIR) polymer composite were introduced. The analysis results indicated that the bulk resistivity decreased greatly with increasing boron carbide content, and when boron carbide content reached to 60%, the bulk resistivity achieved the minimum. Accordingly, electric heating behavior of the composite is strongly dependent on boron carbide content as well as applied voltage. The content of boron carbide was found to be effective in achieving high thermal conductivity in composite systems. The thermal conductivity of the composite material with added boron carbide was improved nearly 20 times than that of the pure IIR. The thermal stability test showed that, compared with pure IIR, the thermal stable time of composites was markedly extended, which indicated that the boron carbide can significantly improve the thermal stability of boron carbide/IIR composite.

  20. Ice thermal storage air conditioning system for electric load leveling; Denryoku heijunka to hyochikunetsu system

    Energy Technology Data Exchange (ETDEWEB)

    Shigenaga, Y. [Daikin Industries Ltd., Osaka (Japan)

    1998-08-15

    Thermal storage air conditioning system is the one to use energy stored into thermal storing materials by using night electric power and to operate effective air conditioning. Therefore, as load can be treated by the stored energy, volume of the apparatus can be reduced. And, by reduction of the consumed power at day time, it can contribute to leveling of electric power demand. In general, there are two types in the thermal storage method: one is a method to store as thermal energy, and the other is that to store as chemical energy. For conditions required for the storing materials, important elements on their actual uses are not only physical properties such as large thermal storage per unit and easy thermal in- and out-puts, but also safety, long-term reliability, and easy receiving and economics containing future. The ice thermal storage air conditioning system is classified at the viewpoint of type of ice, kind of thermal storing medium, melting method on using cooling and heating, kinds of thermal medium on cooling and heating. 3 refs., 5 figs., 2 tabs.

  1. A Power Load Distribution Algorithm to Optimize Data Center Electrical Flow

    Directory of Open Access Journals (Sweden)

    Paulo Maciel

    2013-07-01

    Full Text Available Energy consumption is a matter of common concern in the world today. Research demonstrates that as a consequence of the constantly evolving and expanding field of information technology, data centers are now major consumers of electrical energy. Such high electrical energy consumption emphasizes the issues of sustainability and cost. Against this background, the present paper proposes a power load distribution algorithm (PLDA to optimize energy distribution of data center power infrastructures. The PLDA, which is based on the Ford-Fulkerson algorithm, is supported by an environment called ASTRO, capable of performing the integrated evaluation of dependability, cost and sustainability. More specifically, the PLDA optimizes the flow distribution of the energy flow model (EFM. EFMs are responsible for estimating sustainability and cost issues of data center infrastructures without crossing the restrictions of the power capacity that each device can provide (power system or extract (cooling system. Additionally, a case study is presented that analyzed seven data center power architectures. Significant results were observed, achieving a reduction in power consumption of up to 15.5%.

  2. Functional electrical stimulation of intrinsic laryngeal muscles under varying loads in exercising horses.

    Directory of Open Access Journals (Sweden)

    Jon Cheetham

    Full Text Available Bilateral vocal fold paralysis (BVCP is a life threatening condition and appears to be a good candidate for therapy using functional electrical stimulation (FES. Developing a working FES system has been technically difficult due to the inaccessible location and small size of the sole arytenoid abductor, the posterior cricoarytenoid (PCA muscle. A naturally-occurring disease in horses shares many functional and etiological features with BVCP. In this study, the feasibility of FES for equine vocal fold paralysis was explored by testing arytenoid abduction evoked by electrical stimulation of the PCA muscle. Rheobase and chronaxie were determined for innervated PCA muscle. We then tested the hypothesis that direct muscle stimulation can maintain airway patency during strenuous exercise in horses with induced transient conduction block of the laryngeal motor nerve. Six adult horses were instrumented with a single bipolar intra-muscular electrode in the left PCA muscle. Rheobase and chronaxie were within the normal range for innervated muscle at 0.55±0.38 v and 0.38±0.19 ms respectively. Intramuscular stimulation of the PCA muscle significantly improved arytenoid abduction at all levels of exercise intensity and there was no significant difference between the level of abduction achieved with stimulation and control values under moderate loads. The equine larynx may provide a useful model for the study of bilateral fold paralysis.

  3. A system-level mathematical model for evaluation of power train performance of load-leveled electric-vehicles

    Science.gov (United States)

    Purohit, G. P.; Leising, C. J.

    1984-01-01

    The power train performance of load leveled electric vehicles can be compared with that of nonload leveled systems by use of a simple mathematical model. This method of measurement involves a number of parameters including the degree of load leveling and regeneration, the flywheel mechanical to electrical energy fraction, and efficiencies of the motor, generator, flywheel, and transmission. Basic efficiency terms are defined and representative comparisons of a variety of systems are presented. Results of the study indicate that mechanical transfer of energy into and out of the flywheel is more advantageous than electrical transfer. An optimum degree of load leveling may be achieved in terms of the driving cycle, battery characteristics, mode of mechanization, and the efficiency of the components. For state of the art mechanically coupled flyheel systems, load leveling losses can be held to a reasonable 10%; electrically coupled systems can have losses that are up to six times larger. Propulsion system efficiencies for mechanically coupled flywheel systems are predicted to be approximately the 60% achieved on conventional nonload leveled systems.

  4. The Effect of Electric Load Profiles on the Performance of Off-Grid Residential Hybrid Renewable Energy Systems

    Directory of Open Access Journals (Sweden)

    Stephen Treado

    2015-10-01

    Full Text Available This paper investigates the energy performance of off-grid residential hybrid renewable electric power systems, particularly the effect of electric load profiles on the ability to harvest available solar energy and avoid the consumption of auxiliary energy in the form of propane. The concepts are illustrated by an analysis of the energy performance of electric and propane-fired refrigerators. Off-grid electric power systems frequently incorporate a renewable source, such as wind or solar photovoltaic (PV, with a back-up power provided by a propane fueled motor/generator. Among other design decisions, residential consumers face the choice of employing an electric refrigerator with a conventional vapor compression refrigeration system, or a fuel-fired refrigerator operating as an absorption refrigeration system. One interesting question is whether it is more advantageous from an energy perspective to use electricity to run the refrigerator, which might be provided by some combination of the PV and propane motor/generator, thereby taking advantage of the relatively higher electric refrigerator Coefficient of Performance (COP and free solar energy but having to accept a low electrical conversion efficiency of the motor/generator, or use thermal energy from the combustion of propane to produce the refrigeration effect via an absorption system, albeit with a much lower COP. The analysis is complicated by the fact that most off-grid renewable electrical power systems utilize a battery bank to provide electrical power when it is not available from the wind turbine or PV system, so the state of charge of the battery bank will have a noticeable impact on what energy source is available at any moment in time. Daily electric load profiles combined with variable solar energy input determine the state of charge of the battery bank, with the degree of synchronization between the two being a critical factor in determining performance. The annual energy usage

  5. Load levelling measures being tackled by shikoku Electric Power Co. Inc.; Shikoku Denryoku Kabushi Kaisha no fuka heijunka eno torikumi

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-11-01

    For the electric power companies, the activity of pushing forward the load levelling contributes greatly to the curtailment of cost by means of effective formation and utilization of facilities. It is planned to take up more positive activities with a target of 3% improvement in the load factor in ten years. Concrete measures for further promotion of load levelling are the diversity of the rate menu of appraising the load levelling effort of the customers and the promotion of the spread of equipment and systems relating to load levelling such as electric water heating apparatuses and thermal energy storage air conditioning systems. The rate system has been reviewed taking the opportunity of rate revision made in January, 1996. Particularly, further load shift to midnight time zone is expected as a result of better rate incentive for customers which is brought about by large reduction of the rate level due to the cost reduction effect accompanying the improvement in atomic power generation ratio. Outlines are given on the fields relating to general households, business, dwellings, buildings, and industry. 3 figs., 1 tab.

  6. Tests of an alternating current propulsion subsystem for electric vehicles on a road load simulator

    Science.gov (United States)

    Stenger, F. J.

    1982-01-01

    The test results of a breadboard version of an ac electric-vehicle propulsion subsystem are presented. The breadboard was installed in the NASA Lewis Research Center Road Load Simulator facility and tested under steady-state and transient conditions. Steady-state tests were run to characterize the system and component efficiencies over the complete speed-torque range within the capability of the propulsion subsystem in the motoring mode of operation. Transient tests were performed to determine the energy consumption of the breadboard over the acceleration and cruise portions of SAE J227 and driving schedules B, C, and D. Tests in the regenerative mode were limited to the low-gear-speed range of the two speed transaxle used in the subsystem. The maximum steady-state subsystem efficiency observed for the breadboard was 81.5 percent in the high-gear-speed range in the motoring mode, and 76 percent in the regenerative braking mode (low gear). The subsystem energy efficiency during the transient tests ranged from 49.2 percent for schedule B to 68.4 percent for Schedule D.

  7. Resonant mode behavior of lumped-resistor-loaded electric-inductive-capacitive resonator and its absorber application

    Directory of Open Access Journals (Sweden)

    Hong-Min Lee

    2013-05-01

    Full Text Available This paper presents investigations into the resonant mode behavior of a lumped-resistor-loaded electric-inductive-capacitive (ELC resonator, which is illuminated with a parallel polarization external electromagnetic wave. An ELC resonator exhibits a negative effective permittivity for both parallel and perpendicular polarizations. In contrast to a common ELC resonator, the lumped-resistor-loaded ELC resonator exhibits a switchable resonant mode behavior, thereby revealing a negative effective permeability. In addition, this resonator exhibits a low quality factor owing to the loaded lumped resistors. A metamaterial absorber, which consists of a lumped-resistor-loaded ELC resonator and a cut-wire strip, is designed to confirm the effectiveness of the resonator.

  8. Electric Car Users’ Time of Charging Problem under Peak Load Pricing When Delay in Charging Time Involves Uncertain Cost

    DEFF Research Database (Denmark)

    Fetene, Gebeyehu Manie

    such as electricity, transport (con- gestion), water and telecommunication. Linear and non-linear peak load pricing alternatives have been suggested to curb this problem, particularly when demand is cyclical (Mohsenian-Rad and Leon-Garcia, 2010; Tan and Varaiya, 1993; Chao et al., 1986; Finsinger; Roberts, 1979...... of electricity. The electric vehicle (EV) users choice of time of charging problem under PLP is different from that of general households using energy for house appliances since there is uncertain cost to the former as- sociated with likelihood occurrence of unanticipated trips such as visiting hospital...... and commuting to lately informed social events, etc. In this paper, we consider EV user’s choice of time of charging problem when there is PLP of electricity used for charging the battery of EVs. Specifically, this paper aims to present a model of optimal time of charging when EV users have to trade-of between...

  9. An implementation of particle swarm optimization to evaluate optimal under-voltage load shedding in competitive electricity markets

    Science.gov (United States)

    Hosseini-Bioki, M. M.; Rashidinejad, M.; Abdollahi, A.

    2013-11-01

    Load shedding is a crucial issue in power systems especially under restructured electricity environment. Market-driven load shedding in reregulated power systems associated with security as well as reliability is investigated in this paper. A technoeconomic multi-objective function is introduced to reveal an optimal load shedding scheme considering maximum social welfare. The proposed optimization problem includes maximum GENCOs and loads' profits as well as maximum loadability limit under normal and contingency conditions. Particle swarm optimization (PSO) as a heuristic optimization technique, is utilized to find an optimal load shedding scheme. In a market-driven structure, generators offer their bidding blocks while the dispatchable loads will bid their price-responsive demands. An independent system operator (ISO) derives a market clearing price (MCP) while rescheduling the amount of generating power in both pre-contingency and post-contingency conditions. The proposed methodology is developed on a 3-bus system and then is applied to a modified IEEE 30-bus test system. The obtained results show the effectiveness of the proposed methodology in implementing the optimal load shedding satisfying social welfare by maintaining voltage stability margin (VSM) through technoeconomic analyses.

  10. Multi-Temporal Decomposed Wind and Load Power Models for Electric Energy Systems

    Science.gov (United States)

    Abdel-Karim, Noha

    This thesis is motivated by the recognition that sources of uncertainties in electric power systems are multifold and may have potentially far-reaching effects. In the past, only system load forecast was considered to be the main challenge. More recently, however, the uncertain price of electricity and hard-to-predict power produced by renewable resources, such as wind and solar, are making the operating and planning environment much more challenging. The near-real-time power imbalances are compensated by means of frequency regulation and generally require fast-responding costly resources. Because of this, a more accurate forecast and look-ahead scheduling would result in a reduced need for expensive power balancing. Similarly, long-term planning and seasonal maintenance need to take into account long-term demand forecast as well as how the short-term generation scheduling is done. The better the demand forecast, the more efficient planning will be as well. Moreover, computer algorithms for scheduling and planning are essential in helping the system operators decide what to schedule and planners what to build. This is needed given the overall complexity created by different abilities to adjust the power output of generation technologies, demand uncertainties and by the network delivery constraints. Given the growing presence of major uncertainties, it is likely that the main control applications will use more probabilistic approaches. Today's predominantly deterministic methods will be replaced by methods which account for key uncertainties as decisions are made. It is well-understood that although demand and wind power cannot be predicted at very high accuracy, taking into consideration predictions and scheduling in a look-ahead way over several time horizons generally results in more efficient and reliable utilization, than when decisions are made assuming deterministic, often worst-case scenarios. This change is in approach is going to ultimately require new

  11. Approach undertaken by our Company for leveling electric loads; Chubu Denryoku Kabushi Kaisha no fuka heijunka eno torikumi ni tsuite

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-07-01

    Measures for leveling the electric loads relying upon two facets - tariff system and business activities - in Chubu Electric Power Co., Inc. are presented. Firstly, the existing pricing systems for midnight electric power and electric light according to the period of time for the household as well as those of seasonal and time zone electric power, modifiable contract with the time zone and so forth for large industry users, together with a similar contract for the owner of regenerating installation are outlined. In addition, a price reduction system is indicated in favor of a scheduled shutdown of large industry operations as a means of avoiding electric consumption during weekdays in summer and between 13h and 16h when large demands exist. Further, a selective contract system put in service in 1995 and the price reduction for ice regenerating air conditioning system are cited. As for business facet, 1995 is regarded as the first year of the ice regenerator for its generalization through exhibition and promotive campaign to the foods processing industry, and the application of the latent heat regenerative system to perishable foods is recommended. Moreover, installation of energy saving type automatic vending machine, so-called eco-vendor is encouraged for its merit of peak-cut and energy price lowering. Lastly, activities to extend the use of electric calorifiers and the regenerative floor heating are mentioned. 2 figs., 1 tab.

  12. Prediction of crack density and electrical resistance changes in indium tin oxide/polymer thin films under tensile loading

    KAUST Repository

    Mora Cordova, Angel

    2014-06-11

    We present unified predictions for the crack onset strain, evolution of crack density, and changes in electrical resistance in indium tin oxide/polymer thin films under tensile loading. We propose a damage mechanics model to quantify and predict such changes as an alternative to fracture mechanics formulations. Our predictions are obtained by assuming that there are no flaws at the onset of loading as opposed to the assumptions of fracture mechanics approaches. We calibrate the crack onset strain and the damage model based on experimental data reported in the literature. We predict crack density and changes in electrical resistance as a function of the damage induced in the films. We implement our model in the commercial finite element software ABAQUS using a user subroutine UMAT. We obtain fair to good agreement with experiments. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  13. VOLTAGE STABILITY ASSESSMENT FOR WIND FARMS INTEGRATION INTO ELECTRICITY GRIDS WITH AND WITHOUT CONSIDERATION OF VOLTAGE DEPENDENT LOADS

    Directory of Open Access Journals (Sweden)

    TOMA R.

    2016-09-01

    Full Text Available The paper presents a comparative study between the effects on voltage stability of the integration of a wind farm into the electricity grid with or without voltage dependent loads in the context of different locations of a synchronous compensator from the grid. The P-V curves are built by using the PowerFactory DigSilent 15.2.2 and a DPL script that implements a simplified form of the Continuation Power Flow method.

  14. Analysis Of The Performance Of An Optimization Model For Time-Shiftable Electrical Load Scheduling Under Uncertainty

    Science.gov (United States)

    2016-12-01

    NAVAL POSTGRADUATE SCHOOL MONTEREY, CALIFORNIA THESIS ANALYSIS OF THE PERFORMANCE OF AN OPTIMIZATION MODEL FOR TIME-SHIFTABLE ELECTRICAL LOAD...REPORT TYPE AND DATES COVERED Master’s Thesis 01-04-2016 to 09-23-2016 4. TITLE AND SUBTITLE ANALYSIS OF THE PERFORMANCE OF AN OPTIMIZATIONMODEL FOR...INTENTIONALLY LEFT BLANK ii Approved for public release. Distribution is unlimited. ANALYSIS OF THE PERFORMANCE OF AN OPTIMIZATION MODEL FOR TIME-SHIFTABLE

  15. Modeling and Estimating of Load Demand of Electricity Generated from Hydroelectric Power Plants in Turkey using Machine Learning Methods

    Directory of Open Access Journals (Sweden)

    DURSUN, B.

    2014-02-01

    Full Text Available In this study, the electricity load demand, between 2012 and 2021, has been estimated using the load demand of the electricity generated from hydroelectric power plants in Turkey between 1970 and 2011. Among machine learning algorithms, Multilayer Perceptron, Locally Weighted Learning, Additive Regression, M5Rules and ZeroR classifiers are used to estimate the electricity load demand. Among them, M5Rules and Multilayer Perceptron classifiers are observed to have better performance than the others. ZeroR classifier is a kind of majority classifier used to compare the performances of other classifiers. Locally Weighted Learning and Additive Regression classifiers are Meta classifiers. In the training period conducted by Locally Weighted Learning and Additive Regression classifiers, when Multilayer Perceptron and M5Rules classifiers are chosen respectively, it is possible to obtain models with the highest performance. As a result of the experiments performed using M5Rules and Multilayer Perceptron classifiers, correlation coefficient values of 0.948 and 0.9933 are obtained respectively. And, Mean Absolute Error and Root Mean Squared Error value of Multilayer Perceptron classifier are closer to zero than that of M5Rules classifier. Therefore, it can be said the model performed by Multilayer Perceptron classifier has the best performance compared to the models of other classifiers.

  16. The effect of load and thickness variation on stress analysis of monocoque frame of electric city car using FEM

    Science.gov (United States)

    Makhrojan, Agus; Suprihadi, Agus; Budi, Sigit Setijo; Jamari, J.; Ismail, Rifky

    2017-01-01

    The electric car is transportation which growing and constantly put through improvisation vehicle design. One of the structural components of the electric car which holds a major role is a frame. The purpose of this study is to get monocoque frame design which lightweight and powerful for a city car with two passengers that was able to improve the efficiency of the battery voltage source. Monocoque frame should be able to accept the normal loads such as the weight of batteries, passenger, and body. The most important thing, monocoque frame should also be able to protect the driver and passengers in the event of a collision. Mild steel was chosen for the design because it is easy to obtain and reasonable price as well as easy to shaped for two-seater electric car. FEM (finite element method) was used to determine stress determination and rigidity of the monocoque frame when receiving a static load. The results show that the monocoque frame was still able to withstand the required loads with minimal deflection.

  17. Effects of micro electric current load during cooling of plant tissues on intracellular ice crystal formation behavior and pH.

    Science.gov (United States)

    Ninagawa, Takako; Kawamura, Yukio; Konishi, Tadashi; Narumi, Akira

    2016-08-01

    Cryopreservation techniques are expected to evolve further to preserve biomaterials and foods in a fresh state for extended periods of time. Long-term cryopreservation of living materials such as food and biological tissue is generally achieved by freezing; thus, intracellular freezing occurs. Intracellular freezing injures the cells and leads to cell death. Therefore, a dream cryopreservation technique would preserve the living materials without internal ice crystal formation at a temperature low enough to prevent bacterial activity. This study was performed to investigate the effect of micro electrical current loading during cooling as a new cryopreservation technique. The behavior of intracellular ice crystal formation in plant tissues with or without an electric current load was evaluated using the degree of supercooling, degree of cell deformation, and grain size and growing rate of intracellular ice crystal. Moreover, the transition of intracellular pH during plant tissue cooling with or without electric current loading was also examined using the fluorescence intensity ratio to comprehend cell activity at lower temperatures. The results indicated that micro electric current load did not only decrease the degree of cell deformation and grain size of intracellular ice crystal but also reduced the decline in intracellular pH due to temperature lowering, compared with tissues subjected to the same cooling rate without an electric current load. Thus, the effect of electric current load on cryopreservation and the potential of a new cryopreservation technique using electric current load were discussed based on these results.

  18. Simulation of a current source with a Cole-Cole load for multi-frequency electrical impedance tomography.

    Science.gov (United States)

    Aguiar Santos, Susana; Schlebusch, Thomas; Leonhardt, Steffen

    2013-01-01

    An accurate current source is one of the keys in the hardware of Electrical impedance Tomography systems. Limitations appear mainly at higher frequencies and for non-simple resistive loads. In this paper, we simulate an improved Howland current source with a Cole-Cole load. Simulations comparing two different op-amps (THS4021 and OPA843) were performed at 1 kHz to 1 MHz. Results show that the THS4021 performed better than the OPA843. The current source with THS4021 reaches an output impedance of 20 MΩ at 1 kHz and above 320 kΩ at 1 MHz, it provides a constant and stable output current up to 4 mA, in the complete range of frequencies, and for Cole-Cole (resistive and capacitive) load.

  19. Annual Electric Load Forecasting by a Least Squares Support Vector Machine with a Fruit Fly Optimization Algorithm

    Directory of Open Access Journals (Sweden)

    Bao Wang

    2012-11-01

    Full Text Available The accuracy of annual electric load forecasting plays an important role in the economic and social benefits of electric power systems. The least squares support vector machine (LSSVM has been proven to offer strong potential in forecasting issues, particularly by employing an appropriate meta-heuristic algorithm to determine the values of its two parameters. However, these meta-heuristic algorithms have the drawbacks of being hard to understand and reaching the global optimal solution slowly. As a novel meta-heuristic and evolutionary algorithm, the fruit fly optimization algorithm (FOA has the advantages of being easy to understand and fast convergence to the global optimal solution. Therefore, to improve the forecasting performance, this paper proposes a LSSVM-based annual electric load forecasting model that uses FOA to automatically determine the appropriate values of the two parameters for the LSSVM model. By taking the annual electricity consumption of China as an instance, the computational result shows that the LSSVM combined with FOA (LSSVM-FOA outperforms other alternative methods, namely single LSSVM, LSSVM combined with coupled simulated annealing algorithm (LSSVM-CSA, generalized regression neural network (GRNN and regression model.

  20. Energisation of an MV electric boiler for load control in power systems with large share of renewables

    DEFF Research Database (Denmark)

    Silva, Filipe Miguel Faria da; Bak, Claus Leth; Davidsen, Troels

    2014-01-01

    The intermittence of some renewable energy sources, mainly wind and solar, leads to rapid power variations, which have to be controlled in order to maintain the system stable. Controllable loads, like MW range electric boilers, are a good solution for this problem, as the warmed water can be reused...... and trigger the ground fault protection. This paper uses field measurements made in a boiler installed in a power plant for the analysis of this issue. The measurements are used to design a simulation model of the electric arc, which is used to study different energisation scenarios: With/without isolating......, minimising energy losses. The boilers under analysis in this paper operate by increasing/decreasing the water level. Electric arcs appear between the electrodes and the water surface for a period of approximately 2s during the energisation. These arcs can be seen as faults to ground by the protections relays...

  1. A case study review of technical and technology issues for transition of a utility load management program to provide system reliability resources in restructured electricity markets

    Energy Technology Data Exchange (ETDEWEB)

    Weller, G.H.

    2001-07-15

    Utility load management programs--including direct load control and interruptible load programs--were employed by utilities in the past as system reliability resources. With electricity industry restructuring, the context for these programs has changed; the market that was once controlled by vertically integrated utilities has become competitive, raising the question: can existing load management programs be modified so that they can effectively participate in competitive energy markets? In the short run, modified and/or improved operation of load management programs may be the most effective form of demand-side response available to the electricity system today. However, in light of recent technological advances in metering, communication, and load control, utility load management programs must be carefully reviewed in order to determine appropriate investments to support this transition. This report investigates the feasibility of and options for modifying an existing utility load management system so that it might provide reliability services (i.e. ancillary services) in the competitive markets that have resulted from electricity industry restructuring. The report is a case study of Southern California Edison's (SCE) load management programs. SCE was chosen because it operates one of the largest load management programs in the country and it operates them within a competitive wholesale electricity market. The report describes a wide range of existing and soon-to-be-available communication, control, and metering technologies that could be used to facilitate the evolution of SCE's load management programs and systems to provision of reliability services. The fundamental finding of this report is that, with modifications, SCE's load management infrastructure could be transitioned to provide critical ancillary services in competitive electricity markets, employing currently or soon-to-be available load control technologies.

  2. Mechano-electric Effect of Hardened Cement Paste During Quasi-static Loading

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Mechano-electric effect of cement paste was investigated in this paper. As compressive stress was applied on the specimen, an electrical current was observed. The intensity of the electrical current increased with stress increasing, and decreased with stress decreasing. Different measurement methods were also discussed in this paper. This phenomenon was related to the electrokinetic phenomenon of solid/liquid interface in cement paste. The study on mechano-electric effect of hardened cement paste provides a new method for making smart concrete structures.

  3. Direct participation of electrical loads in the California independent system operator markets during the Summer of 2000

    Energy Technology Data Exchange (ETDEWEB)

    Marnay, Chris; Hamachi, Kristina S.; Khavkin, Mark; Siddiqui, Afzal S.

    2001-04-01

    California's restructured electricity markets opened on 1 April 1998. The former investor-owned utilities were functionally divided into generation, transmission, and distribution activities, all of their gas-fired generating capacity was divested, and the retail market was opened to competition. To ensure that small customers shared in the expected benefit of lower prices, the enabling legislation mandated a 10% rate cut for all customers, which was implemented in a simplistic way that fossilized 1996 tariff structures. Rising fuel and environmental compliance costs, together with a reduced ability to import electricity, numerous plant outages, and exercise of market power by generators drove up wholesale electricity prices steeply in 2000, while retail tariffs remained unchanged. One of the distribution/supply companies entered bankruptcy in April 2001, and another was insolvent. During this period, two sets of interruptible load programs were in place, longstanding ones organized as special tariffs by the distribution/supply companies and hastily established ones run directly by the California Independent System Operator (CAISO). The distribution/supply company programs were effective at reducing load during the summer of 2000, but because of the high frequency of outages required by a system on the brink of failure, customer response declined and many left the tariff. The CAISO programs failed to attract enough participation to make a significant difference to the California supply demand imbalance. The poor performance of direct load participation in California's markets reinforces the argument for accurate pricing of electricity as a stimulus to energy efficiency investment and as a constraint on market volatility.

  4. IoT-based electricity load optimisation: initial results of a monitor and control system

    CSIR Research Space (South Africa)

    Smith, Andrew C

    2012-11-01

    Full Text Available The demand for electrical energy is increasing globally. Both the average as well as the anticipated peak demand must be considered by the supplier when designing an electrical supply. We present an Internet of Things – based system, and a concept...

  5. Efforts of load leveling in Tohoku Electric Power Co. Inc.; Tohoku denryoku no fuka heijunka eno torikumi ni tsuite

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-05-01

    This paper describes efforts of load leveling in Tohoku Electric Power Co., Inc. from the viewpoint of the rate system and business development. For the approach from the rate system, various rate menus for the peak shift have been arranged for domestic and large industry customers. To create the midnight demand, spread and expansion of electric hot water service are promoted. Consequently, the contract of midnight power has reached 914,000 kW at the end of 1995, which was 774,000 kW in 1985. To spread the ice regenerative air conditioning systems, the grant of incentive to the manufacturers and special discount of electricity rate have been conducted. These systems have been introduced in the eight places of Tohoku Electric Power`s business. The spread incident system has been created to introduce the automatic vending machines for beverages with the power peak cut function. Unused energy, such as exhaust heat from the non-treated sewage water and substations has been utilized as a heat supply project for city redevelopment. Multi-functional heat pump with regenerative function has been developed. This system aims at the peak shift by combining multi-functional heat pump and electric hot water service. 2 figs., 2 tabs.

  6. To Problem Pertaining to Provision of Electric Power Load Schedules of Power Sys- tems while Involving Potential of Power Technological Sources of Industrial Enterprises

    Directory of Open Access Journals (Sweden)

    B. M. Khroustalev

    2010-01-01

    Full Text Available The paper considers a possibility to use co-generated complexes having heat technological industrial load for operation in accordance with the requirements of irregularity of electric power generation schedule.

  7. 电动负载模拟系统仿真研究%Electric load simulation system simulation research

    Institute of Scientific and Technical Information of China (English)

    陈家新; 张筑亚; 杨达勇

    2016-01-01

    电动负载模拟器是一种能精确控制输出转矩的系统,是科学试验、工业生产中用来模拟机械负载的重要设备之一。论文分析了以永磁同步电机为加载电机的负载模拟器的工作原理,推导、构建了系统的数学模型。采用经典PID算法对转矩、电流进行闭环控制,并引入前馈补偿,抑制由被加载对象主动运动引起的多余力矩,实现系统的快响应、高精度控制。最后借助MATLAB/Simulink验证系统可行性,参照负载模拟器的评价指标体系讨论系统性能。%Electric load simulator is a precise control of the output torque of the system, is a scientific experiment, industrial production equipment used to simulate one of the important mechanical load. This paper analyzes the permanent magnet synchronous motor is loaded with the motor load simulator works derived construct a mathematical model of the system. Classic PID algorithm torque, current loop control, and before the introduction of feed-forward compensation, inhibit the excess torque load objects from being active movement caused by the fast response of the system to achieve high-precision control. Finally With MATLAB/Simulink to verify the feasibility of the system, the reference load simulator evaluation system discussion system performance.

  8. Heating load of buildings. Room heat from decentralized renewable electricity; Heizlast von Gebaeuden. Raumwaerme aus dezentral erneuerbarem Strom

    Energy Technology Data Exchange (ETDEWEB)

    Hartmann, Frank

    2013-10-15

    If one would like to get the heating load of a building by using peripheral generated electrical energy from photovoltaics or small wind power, one must deal with both the specific building, as well as the heating load, the heating temperature limit and the differentiation of specific heating period for the building. Here, a ground source heat pump with an intelligent energy storage system seems to be the first choice. [German] Moechte man mit dezentral erzeugter elektrischer Energie aus Photovoltaik oder Kleinst-Windkraft die Heizlast eines Gebaeudes besorgen, muss man sich sowohl mit dem spezifischen Gebaeude, als auch mit der Heizlast, der Heizgrenztemperatur und der Differenzierung der spezifischen Heizperiode fuer das Gebaeude auseinandersetzen. Dabei scheint eine erdgekoppelte Waermepumpe mit einem intelligenten Speichersystem die erste Wahl.

  9. Load Frequency Control in Isolated Micro-Grids with Electrical Vehicles Based on Multivariable Generalized Predictive Theory

    Directory of Open Access Journals (Sweden)

    Jun Yang

    2015-03-01

    Full Text Available In power systems, although the inertia energy in power sources can partly cover power unbalances caused by load disturbance or renewable energy fluctuation, it is still hard to maintain the frequency deviation within acceptable ranges. However, with the vehicle-to-grid (V2G technique, electric vehicles (EVs can act as mobile energy storage units, which could be a solution for load frequency control (LFC in an isolated grid. In this paper, a LFC model of an isolated micro-grid with EVs, distributed generations and their constraints is developed. In addition, a controller based on multivariable generalized predictive control (MGPC theory is proposed for LFC in the isolated micro-grid, where EVs and diesel generator (DG are coordinated to achieve a satisfied performance on load frequency. A benchmark isolated micro-grid with EVs, DG, and wind farm is modeled in the Matlab/Simulink environment to demonstrate the effectiveness of the proposed method. Simulation results demonstrate that with MGPC, the energy stored in EVs can be managed intelligently according to LFC requirement. This improves the system frequency stability with complex operation situations including the random renewable energy resource and the continuous load disturbances.

  10. Provision of Flexible Load Control by Multi-Flywheel-Energy-Storage System in Electrical Vehicle Charging Stations

    DEFF Research Database (Denmark)

    Sun, Bo; Dragicevic, Tomislav; Andrade, Fabio

    2015-01-01

    Electrical vehicle (EV) chargers are going to occupy a considerable portion of total energy consumption in the future smart grid. Fast charging stations (FCS), as the most demanding representatives of charging infrastructure, will be requested to provide some ancillary services to the power system...... in order to support basic electrical operation. This paper proposes a local implementation of a hysteresis-based aggregation algorithm for coordinated control of multiple stations that can provide functions such as peak shaving, spinning reserves, frequency control, regulation and load following. Local...... stability. Finally, corresponding hardware in the loop results based on dSPACE1006 platform have been reported in order to verify the validity of proposed approach....

  11. L-Tyrosine-loaded nanoparticles increase the antitumoral activity of direct electric current in a metastatic melanoma cell model

    Directory of Open Access Journals (Sweden)

    Vânia Emerich Bucco de Campos

    2010-11-01

    Full Text Available Vânia Emerich Bucco de Campos1, Cesar Augusto Antunes Teixeira1, Venicio Feo da Veiga2, Eduardo Ricci Júnior1, Carla Holandino11Departamento de Medicamentos, Faculdade de Farmácia, 2Instituto de Microbiologia Professor Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, BrazilAbstract: Inhibition of tumor growth induced by treatment with direct electric current (DC has been reported in several models. One of the mechanisms responsible for the antitumoral activity of DC is the generation of oxidative species, known as chloramines. With the aim of increasing chloramine production in the electrolytic medium and optimizing the antitumoral effects of DC, poly(e-caprolactone (PCL nanoparticles (NPs loaded with the amino acid tyrosine were obtained. The physical–chemical characterization showed that the NPs presented size in nanometric range and monomodal distribution. A slightly negative electrokinetic potential was also found in both blank NPs and L-tyrosine-loaded PCL NPs. The yield of the loading process was approximately 50%. Within 3 h of dissolution assay, a burst release of about 80% L-tyrosine was obtained. The in vitro cytotoxicity of DC was significantly increased when associated with L-tyrosine-loaded NPs, using a murine multidrug-resistant melanoma cell line model. This study showed that the use of the combination of nanotechnology and DC has a promising antineoplastic potential and opens a new perspective in cancer therapy.Keywords: direct electric current, nanotechnology, cancer therapy, L-tyrosine, B16F10 cells

  12. Engine control strategy for a series hybrid electric vehicle incorporating load-leveling and computer controlled energy management

    Energy Technology Data Exchange (ETDEWEB)

    Hochgraf, C.G.; Ryan, M.J.; Wiegman, H.L. [Univ. of Wisconsin, Madison, WI (United States)

    1996-09-01

    This paper identifies important engine, alternator and battery characteristics needed for determining an appropriate engine control strategy for a series hybrid electric vehicle. Examination of these characteristics indicates that a load-leveling strategy applied to the small engine will provide better fuel economy than a power-tracking scheme. An automatic energy management strategy is devised whereby a computer controller determines the engine-alternator turn-on and turn-off conditions and controls the engine-alternator autonomously. Battery state of charge is determined from battery voltage and current measurements. Experimental results of the system`s performance in a test vehicle during city driving are presented.

  13. Approach to load leveling in Kansai Electric Power Co. Inc.; Kansai Denryoku no fuka heijunka eno torikumi

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-09-01

    This paper presents an electric hot-water heater and ice storage air conditioning system as systems to be recommended for load leveling. Electric hot-water heater is featured by safety, cleanliness, silence and convenience because of no use of fire. Its electricity charge is only 7.15 yen/kWh less than 1/3 of that for ordinary homes because of use of midnight power. Mainly used MPU-control type electric hot-water heater is more economical because of a 15% discount system. Ice storage air conditioning system is operated in the daytime using ice made by midnight power. It is featured by reduction of facility and installation costs due to the small capacity of heat source equipment, use of inexpensive midnight power, and reduction of running cost due to small contract demand. However, since an ice storage air conditioning system is in the initial stage of diffusion, its initial cost is expensive as compared with conventional non-heat storage air conditioning systems, remaining the issue of cost reduction. 3 figs., 1 tab.

  14. Managing charging loads of electric vehicles by monetary incentives. A model-based optimization; Monetaere Anreize zur Steuerung der Ladelast von Elektrofahrzeugen. Eine modellgestuetzte Optimierung

    Energy Technology Data Exchange (ETDEWEB)

    Paetz, Alexandra-Gwyn; Kaschub, Thomas; Kopp, Martin; Jochem, Patrick; Fichtner, Wolf [Karlsruher Institut fuer Technologie, Karlsruhe (Germany). Inst. fuer Industriebetriebslehre und Industrielle Produktion

    2013-03-15

    Electric mobility is supposed to contribute to climate policy targets by reducing CO{sub 2}-emissions in the transportation sector. Increasing penetration rates of electric vehicles (EV) can lead to new challenges in the electricity sector, especially with regard to local distribution networks. Thus the management of charging loads is discussed as a key issue in energy economics. Due to their long parking times, high electricity and power demand, EV seem to be predestined for load management. Monetary incentives as dynamic pricing can be suitable for that: They reflect the current supply situation, pass the information to the consumers and can thus lead to a corresponding charging behaviour. In this article we analyse this interaction between dynamic pricing and charging loads. For this reason we have developed the optimization model DS-Opt+. It models a total number of 4,000 households in two residential areas of a major city with regard to its electricity demand, its mobility behaviour and its equipment of photovoltaic systems. Four different pricing models are tested for their effects on charging behaviour and thus the total load of the residential area. The results illustrate that only fairly high penetration rates of EV lead to remarkably higher electricity demand and require some load management. The tested dynamic pricing models are suitable for influencing charging loads; load-based tariffs are best in achieving a balanced load curve. In our analysis uncontrolled charging strategies are superior regarding a balanced load curve than controlled strategies by time-varying tariffs. Our results lead to several implications relevant for the energy industry and further research.

  15. Battery engineering problems in designing an electrical load leveling plant for lithium/iron-sulfide cells

    Energy Technology Data Exchange (ETDEWEB)

    Zivi, S. M.; Pollack, I.; Kacinskas, H.; Chilenskas, A. A.; Barney, D. L.; Sudar, S.; Goldstein, I.; Grieve, W.

    1979-01-01

    The design of a lithium/iron sulfide battery for utility load leveling is strongly dependent on the energy capacity selected for the cells. Battery hardware costs are minimized by the selection of large cells, with 30-kWh cells being the largest that would be consistent with system constraints in a 100-MWh load leveling plant. However, it is anticipated that such large cells may be precluded by system reliability and maintainability considerations, and cell capacities on the order of 1 kWh may be needed to satisfy those requirements. Large cells can be protected against overcharge by electronically controlled charge equalization systems that have been developed for experimental eV batteries. The economics of electronically controlled equalization becomes unfavorable for small load-leveling cells; and if small cells are selected, it will be necessary to develop inherent protective means within each cell, with respect to overcharge.

  16. Effect of elastic and plastic tensile mechanical loading on the magnetic properties of NGO electrical steel

    Science.gov (United States)

    Leuning, N.; Steentjes, S.; Schulte, M.; Bleck, W.; Hameyer, K.

    2016-11-01

    The magnetic properties of non-grain-oriented (NGO) electrical steels are highly susceptible to mechanical stresses, i.e., residual, external or thermal ones. For rotating electrical machines, mechanical stresses are inevitable and originate from different sources, e.g., material processing, machine manufacturing and operating conditions. The efficiency and specific losses are largely altered by different mechanical stress states. In this paper the effect of tensile stresses and plastic deformations on the magnetic properties of a 2.9 wt% Si electrical steel are studied. Particular attention is paid to the effect of magnetic anisotropy, i.e., the influence of the direction of applied mechanical stress with respect to the rolling direction. Due to mechanical stress, the induced anisotropy has to be evaluated as it is related to the stress-dependent magnetostriction constant and the grain alignment.

  17. Probabilistic modeling of nodal electric vehicle load due to fast charging stations

    DEFF Research Database (Denmark)

    Tang, Difei; Wang, Peng; Wu, Qiuwei

    2016-01-01

    station into consideration. Fuzzy logic inference system is applied to simulate the charging decision of EV drivers at fast charging station. Due to increasing EV loads in power system, the potential traffic congestion in fast charging stations is modeled and evaluated by queuing theory with spatial...

  18. Load demand profile for a large charging station of a fleet of all-electric plug-in buses

    Directory of Open Access Journals (Sweden)

    Mario A. Rios

    2014-08-01

    Full Text Available This study proposes a general procedure to compute the load demand profile from a parking lot where a fleet of buses with electric propulsion mechanisms are charged. Such procedure is divided in three different stages, the first one models the daily energy utilisation of the batteries based on Monte Carlo simulations and route characteristics. The second one models the process in the charging station based on discrete event simulation of queues of buses served by a lot of available chargers. The third step computes the final demand profile in the parking lot because of the charging process based on the power consumption of batteries’ chargers and the utilisation of the available charges. The proposed procedure allows the computation of the number of required batteries’ chargers to be installed in a charging station placed at a parking lot in order to satisfy and ensure the operation of the fleet, the computation of the power demand profile and the peak load and the computation of the general characteristics of electrical infrastructure to supply the power to the station.

  19. Economic assessment of electric energy storage for load shifting in positive energy building

    DEFF Research Database (Denmark)

    Dumont, Olivier; Do Carmo, Carolina Madeira Ramos; Georges, Emeline

    2017-01-01

    Net zero energy buildings and positive energy buildings are gaining more and more interest. This paper evaluates the impact of the integration of a battery in a positive energy building used to increase its self-consumption of electricity. Parametric studies are carried out by varying the buildin...... and a 3.7 kWh battery. Finally, simple correlations (based on the feed-in tariff, the annual electrical consumption and production) to predict the optimal size of battery and the lowest payback period are proposed.......Net zero energy buildings and positive energy buildings are gaining more and more interest. This paper evaluates the impact of the integration of a battery in a positive energy building used to increase its self-consumption of electricity. Parametric studies are carried out by varying the building...... envelope characteristics, the power supply system, the climate, the lighting and appliances profiles, the roof tilt angle, the battery size and the electricity tariffs, leading to 3200 cases. The analysis is performed on an annual basis in terms of self-consumption and self-production rate and payback...

  20. Control of thumb force using surface functional electrical stimulation and muscle load sharing

    NARCIS (Netherlands)

    Westerveld, A.J.; Schouten, A.C.; Veltink, P.H.; Van der Kooij, H.

    2013-01-01

    Background Stroke survivors often have difficulties in manipulating objects with their affected hand. Thumb control plays an important role in object manipulation. Surface functional electrical stimulation (FES) can assist movement. We aim to control the 2D thumb force by predicting the sum of indiv

  1. Control of thumb force using surface functional electrical stimulation and muscle load sharing

    NARCIS (Netherlands)

    Westerveld, Ard; Westerveld, Ard J.; Schouten, Alfred Christiaan; Veltink, Petrus H.; van der Kooij, Herman

    2013-01-01

    Background: Stroke survivors often have difficulties in manipulating objects with their affected hand. Thumb control plays an important role in object manipulation. Surface functional electrical stimulation (FES) can assist movement. We aim to control the 2D thumb force by predicting the sum of

  2. Control of thumb force using surface functional electrical stimulation and muscle load sharing

    NARCIS (Netherlands)

    Westerveld, A.J.; Schouten, A.C.; Veltink, P.H.; Van der Kooij, H.

    2013-01-01

    Background Stroke survivors often have difficulties in manipulating objects with their affected hand. Thumb control plays an important role in object manipulation. Surface functional electrical stimulation (FES) can assist movement. We aim to control the 2D thumb force by predicting the sum of

  3. The prediction of the impact of climatic factors on short-term electric power load based on the big data of smart city

    Science.gov (United States)

    Qiu, Yunfei; Li, Xizhong; Zheng, Wei; Hu, Qinghe; Wei, Zhanmeng; Yue, Yaqin

    2017-08-01

    The climate changes have great impact on the residents’ electricity consumption, so the study on the impact of climatic factors on electric power load is of significance. In this paper, the effects of the data of temperature, rainfall and wind of smart city on short-term power load is studied to predict power load. The authors studied the relation between power load and daily temperature, rainfall and wind in the 31 days of January of one year. In the research, the authors used the Matlab neural network toolbox to establish the combinational forecasting model. The authors trained the original input data continuously to get the internal rules inside the data and used the rules to predict the daily power load in the next January. The prediction method relies on the accuracy of weather forecasting. If the weather forecasting is different from the actual weather, we need to correct the climatic factors to ensure accurate prediction.

  4. Plug-in Hybrid Electric Vehicles in the Smart Grid Environment: An Economic Model of Load Management by Demand Response

    Directory of Open Access Journals (Sweden)

    Poudineh R.

    2012-10-01

    Full Text Available Environmental concern regarding the consumption of fossil fuels is among the most serious challenges facing the world. As a result, utilisation of more renewable resources and promotion of a clean transport system such as the use of Plug in Hybrid Electric Vehicles (PHEVs became the forefront of the new energy policies. However, the breakthrough of PHEVs in the automotive fleet increases concerns around the stability of power system and in particular, the power network. This research simulates the aggregate load profile of the UK with presence of PHEVs based upon different price scenarios. The results show that under the fixed rate and time of use programmes in the current grid, the extra load of the electric vehicles intensifies the consumption profile and also creates new critical points. Thus, there should always be excess standby capacity to satisfy peak demand even for a short period of time. On the other hand, when the consumers do not pay the price based on the actual cost of supply, those who consume less in peak hours subsidise the ones who consume more and this cross subsidy raises a regulatory issue. On the contrary, a smart grid can accommodate PHEVs without creating technical and regulatory problems. This positive consequence is the result of demand response to the real time pricing. From a technical point of view, the biggest chunk of PHEVs' load will be shifted to the late evening and the hours of minimum demand. Besides, from a welfare analysis standpoint, real time pricing creates no deadweight losses and corresponding demand response will limit the ability of suppliers to increase the spot market clearing price above its equilibrium level.

  5. Demand response-enabled model predictive HVAC load control in buildings using real-time electricity pricing

    Science.gov (United States)

    Avci, Mesut

    A practical cost and energy efficient model predictive control (MPC) strategy is proposed for HVAC load control under dynamic real-time electricity pricing. The MPC strategy is built based on a proposed model that jointly minimizes the total energy consumption and hence, cost of electricity for the user, and the deviation of the inside temperature from the consumer's preference. An algorithm that assigns temperature set-points (reference temperatures) to price ranges based on the consumer's discomfort tolerance index is developed. A practical parameter prediction model is also designed for mapping between the HVAC load and the inside temperature. The prediction model and the produced temperature set-points are integrated as inputs into the MPC controller, which is then used to generate signal actions for the AC unit. To investigate and demonstrate the effectiveness of the proposed approach, a simulation based experimental analysis is presented using real-life pricing data. An actual prototype for the proposed HVAC load control strategy is then built and a series of prototype experiments are conducted similar to the simulation studies. The experiments reveal that the MPC strategy can lead to significant reductions in overall energy consumption and cost savings for the consumer. Results suggest that by providing an efficient response strategy for the consumers, the proposed MPC strategy can enable the utility providers to adopt efficient demand management policies using real-time pricing. Finally, a cost-benefit analysis is performed to display the economic feasibility of implementing such a controller as part of a building energy management system, and the payback period is identified considering cost of prototype build and cost savings to help the adoption of this controller in the building HVAC control industry.

  6. Neurite, a finite difference large scale parallel program for the simulation of electrical signal propagation in neurites under mechanical loading.

    Directory of Open Access Journals (Sweden)

    Julián A García-Grajales

    Full Text Available With the growing body of research on traumatic brain injury and spinal cord injury, computational neuroscience has recently focused its modeling efforts on neuronal functional deficits following mechanical loading. However, in most of these efforts, cell damage is generally only characterized by purely mechanistic criteria, functions of quantities such as stress, strain or their corresponding rates. The modeling of functional deficits in neurites as a consequence of macroscopic mechanical insults has been rarely explored. In particular, a quantitative mechanically based model of electrophysiological impairment in neuronal cells, Neurite, has only very recently been proposed. In this paper, we present the implementation details of this model: a finite difference parallel program for simulating electrical signal propagation along neurites under mechanical loading. Following the application of a macroscopic strain at a given strain rate produced by a mechanical insult, Neurite is able to simulate the resulting neuronal electrical signal propagation, and thus the corresponding functional deficits. The simulation of the coupled mechanical and electrophysiological behaviors requires computational expensive calculations that increase in complexity as the network of the simulated cells grows. The solvers implemented in Neurite--explicit and implicit--were therefore parallelized using graphics processing units in order to reduce the burden of the simulation costs of large scale scenarios. Cable Theory and Hodgkin-Huxley models were implemented to account for the electrophysiological passive and active regions of a neurite, respectively, whereas a coupled mechanical model accounting for the neurite mechanical behavior within its surrounding medium was adopted as a link between electrophysiology and mechanics. This paper provides the details of the parallel implementation of Neurite, along with three different application examples: a long myelinated axon

  7. Neurite, a finite difference large scale parallel program for the simulation of electrical signal propagation in neurites under mechanical loading.

    Science.gov (United States)

    García-Grajales, Julián A; Rucabado, Gabriel; García-Dopico, Antonio; Peña, José-María; Jérusalem, Antoine

    2015-01-01

    With the growing body of research on traumatic brain injury and spinal cord injury, computational neuroscience has recently focused its modeling efforts on neuronal functional deficits following mechanical loading. However, in most of these efforts, cell damage is generally only characterized by purely mechanistic criteria, functions of quantities such as stress, strain or their corresponding rates. The modeling of functional deficits in neurites as a consequence of macroscopic mechanical insults has been rarely explored. In particular, a quantitative mechanically based model of electrophysiological impairment in neuronal cells, Neurite, has only very recently been proposed. In this paper, we present the implementation details of this model: a finite difference parallel program for simulating electrical signal propagation along neurites under mechanical loading. Following the application of a macroscopic strain at a given strain rate produced by a mechanical insult, Neurite is able to simulate the resulting neuronal electrical signal propagation, and thus the corresponding functional deficits. The simulation of the coupled mechanical and electrophysiological behaviors requires computational expensive calculations that increase in complexity as the network of the simulated cells grows. The solvers implemented in Neurite--explicit and implicit--were therefore parallelized using graphics processing units in order to reduce the burden of the simulation costs of large scale scenarios. Cable Theory and Hodgkin-Huxley models were implemented to account for the electrophysiological passive and active regions of a neurite, respectively, whereas a coupled mechanical model accounting for the neurite mechanical behavior within its surrounding medium was adopted as a link between electrophysiology and mechanics. This paper provides the details of the parallel implementation of Neurite, along with three different application examples: a long myelinated axon, a segmented

  8. Assessment and Methods for Supply-Following Loads in Modern Electricity Grids with Deep Renewables Penetration

    Science.gov (United States)

    2013-12-18

    Generation Type Capacity / Peak (GW ) Total Energy (%) Capacity/Load Factors (%) Renewables Geothermal 2.600 / 1.095 3.8% 38.7% / 92.0% Biomass/Biogas...fossil fuel needs can apply to other generation types as well. For example, geothermal , biomass, and biogas facilities all may have flexibility in... power plant , or flexible refrigerators could flatten duration curves of fossil fuel resources rather than the total demand on the grid, perhaps

  9. Influence of applied load on wear behavior of C/C-Cu composites under electric current

    Directory of Open Access Journals (Sweden)

    Jian Yin

    2017-04-01

    Full Text Available Using carbon fiber needled fabrics with Cu-mesh and graphite powder as the preform, Cu mesh modified carbon/carbon(C/C-Cu composites were prepared by chemical vapor deposition (CVD with C3H6 and impregnation-carbonization (I/C with furan resin. C/C composites, as a comparison, were also prepared. Their microstructures and wear morphologies were observed by optical microscopy (OM and scanning electron microscope (SEM, respectively. Wear behavior of C/C and C/C-Cu composites under different applied loads were investigated on a pin-on-disc wear tester. The results show that Cu meshes are well dispersed and pyrolytic carbon is in rough laminar structure. Both C/C and C/C-Cu composites had good wear properties. The current-carrying capacity of C/C-Cu composites increases and the arc discharge is hindered as the applied load increases from 40 N to 80 N. Both C/C and C/C-Cu composites had good wear properties. The mass wear rate of C/C-Cu composites under 80 N was only 4.2% of that under 60 N. In addition, C/C-Cu composites represent different wear behaviors because wear mechanisms of arc erosion, abrasive wear, adhesive wear, and oxidative wear are changing under different applied loads.

  10. Road load simulator tests of the Gould phase 1 functional model silicon controlled rectifier ac motor controller for electric vehicles

    Science.gov (United States)

    Gourash, F.

    1984-02-01

    The test results for a functional model ac motor controller for electric vehicles and a three-phase induction motor which were dynamically tested on the Lewis Research Center road load simulator are presented. Results show that the controller has the capability to meet the SAE-J227a D cycle test schedule and to accelerate a 1576-kg (3456-lb) simulated vehicle to a cruise speed of 88.5 km/hr (55 mph). Combined motor controller efficiency is 72 percent and the power inverter efficiency alone is 89 percent for the cruise region of the D cycle. Steady state test results for motoring, regeneration, and thermal data obtained by operating the simulator as a conventional dynamometer are in agreement with the contractor's previously reported data. The regeneration test results indicate that a reduction in energy requirements for urban driving cycles is attainable with regenerative braking. Test results and data in this report serve as a data base for further development of ac motor controllers and propulsion systems for electric vehicles. The controller uses state-of-the-art silicon controlled rectifier (SCR) power semiconductors and microprocessor-based logic and control circuitry. The controller was developed by Gould Laboratories under a Lewis contract for the Department of Energy's Electric and Hybrid Vehicle program.

  11. Road load simulator tests of the Gould phase 1 functional model silicon controlled rectifier ac motor controller for electric vehicles

    Science.gov (United States)

    Gourash, F.

    1984-01-01

    The test results for a functional model ac motor controller for electric vehicles and a three-phase induction motor which were dynamically tested on the Lewis Research Center road load simulator are presented. Results show that the controller has the capability to meet the SAE-J227a D cycle test schedule and to accelerate a 1576-kg (3456-lb) simulated vehicle to a cruise speed of 88.5 km/hr (55 mph). Combined motor controller efficiency is 72 percent and the power inverter efficiency alone is 89 percent for the cruise region of the D cycle. Steady state test results for motoring, regeneration, and thermal data obtained by operating the simulator as a conventional dynamometer are in agreement with the contractor's previously reported data. The regeneration test results indicate that a reduction in energy requirements for urban driving cycles is attainable with regenerative braking. Test results and data in this report serve as a data base for further development of ac motor controllers and propulsion systems for electric vehicles. The controller uses state-of-the-art silicon controlled rectifier (SCR) power semiconductors and microprocessor-based logic and control circuitry. The controller was developed by Gould Laboratories under a Lewis contract for the Department of Energy's Electric and Hybrid Vehicle program.

  12. Electricity use and load management in electricity heated one-family houses from customer and utility perspective; Effekten av effekten - Elanvaendning och laststyrning i elvaermda smaahus ur kund- och foeretagsperspektiv

    Energy Technology Data Exchange (ETDEWEB)

    Sernhed, Kerstin

    2004-11-01

    Until recently, the increase in electricity demand and peak power demand has been met by expansion of the electricity production. Today, due to the deregulation of the electricity market, the production capacity is decreasing. Therefore, there is a national interest in finding solutions to peak problems also on the demand side. In the studies described here (Study 1 and 2) ten households in electrically heated houses were examined. In 1999 the utility equipped their customers with a remote metering system (CustCom) that has an in-built load control component. In Study 1, the load pattern of ten households was examined by using energy diaries combined with frequent meter readings (every five minutes) of the load demand for heating, hot water service and domestic electricity use. Household members kept energy diaries over a four-day period in January 2004, noting time, activities and the use of household appliances that run on electricity. The analysis showed that the use of heat-producing household appliances, e.g. sauna, washing machine and dryer, appliances used for cooking, dishwasher and extra electric heaters, contribute to the household's highest peaks. Turning on the sauna and at the same time using the shower equates to a peak load of 7-9 kW. This, in addition to the use of electricity for heating and lighting along alongside electricity use for refrigerators and freezers, results in some households reaching their main fuse level (roughly 13,8 kW for a main fuse of 20 A). This means that the domestic use of electricity makes up a considerable part of the highest peak loads in a household, but the highest peaks occur together with the use of electricity for heating and hot water. In the second study, Study 2, the households participated in a load control experiment, in which the utility was able to turn on and switch off the heating and hot water systems remotely, using the CustCom system. Heating and water heaters were switched off for periods of 1

  13. Day-Ahead Short-Term Forecasting Electricity Load via Approximation

    Science.gov (United States)

    Khamitov, R. N.; Gritsay, A. S.; Tyunkov, D. A.; E Sinitsin, G.

    2017-04-01

    The method of short-term forecasting of a power consumption which can be applied to short-term forecasting of power consumption is offered. The offered model is based on sinusoidal function for the description of day and night cycles of power consumption. Function coefficients - the period and amplitude are set up is adaptive, considering dynamics of power consumption with use of an artificial neural network. The presented results are tested on real retrospective data of power supply company. The offered method can be especially useful if there are no opportunities of collection of interval indications of metering devices of consumers, and the power supply company operates with electrical supply points. The offered method can be used by any power supply company upon purchase of the electric power in the wholesale market. For this purpose, it is necessary to receive coefficients of approximation of sinusoidal function and to have retrospective data on power consumption on an interval not less than one year.

  14. Green neighbourhoods in low voltage networks: measuring impact of electric vehicles and photovoltaics on load profiles

    CERN Document Server

    Hattam, Laura

    2016-01-01

    In the near future various types of low-carbon technologies (LCTs) are expected to be widely employed throughout the United Kingdom. However, the effect that these technologies will have at a household level on the existing low voltage (LV) network is still an area of extensive research. We propose an agent based model that estimates the growth of LCTs within local neighbourhoods, where social influence is imposed. Real-life data from a LV network is used that comprises of many socially diverse neighbourhoods. Both electric vehicle uptake and the combined scenario of electric vehicle and photovoltaic adoption are investigated with this data. A probabilistic approach is outlined, which determines lower and upper bounds for the model response at every neighbourhood. This technique is used to assess the implications of modifying model assumptions and introducing new model features. Moreover, we discuss how the calculation of these bounds can inform future network planning decisions.

  15. Analysis of the axial electric field in a plasma-loaded-helix travelling wave tube

    Institute of Scientific and Technical Information of China (English)

    Xie Hong-Quan; Liu Pu-Kun

    2006-01-01

    A helix type slow wave structure filled with plasma is immersed in a strong longitudinal magnetic field. Taking into account the effect of the plasma and the dielectric, the system is separated radially into three regions. By means of the sheath model and Maxwell equation, the distribution of the electromagnetic field is established. Using the boundary conditions of each region, the dispersion relation of the slow wave structure is derived. The trend of change for the radial profile of the axial electric field is analysed respectively in different plasma densities, plasma column radius and dielectric constant by numerical computation. Some useful results are obtained on the basis of the discussion.

  16. Electric Load Forecasting Based on a Least Squares Support Vector Machine with Fuzzy Time Series and Global Harmony Search Algorithm

    Directory of Open Access Journals (Sweden)

    Yan Hong Chen

    2016-01-01

    Full Text Available This paper proposes a new electric load forecasting model by hybridizing the fuzzy time series (FTS and global harmony search algorithm (GHSA with least squares support vector machines (LSSVM, namely GHSA-FTS-LSSVM model. Firstly, the fuzzy c-means clustering (FCS algorithm is used to calculate the clustering center of each cluster. Secondly, the LSSVM is applied to model the resultant series, which is optimized by GHSA. Finally, a real-world example is adopted to test the performance of the proposed model. In this investigation, the proposed model is verified using experimental datasets from the Guangdong Province Industrial Development Database, and results are compared against autoregressive integrated moving average (ARIMA model and other algorithms hybridized with LSSVM including genetic algorithm (GA, particle swarm optimization (PSO, harmony search, and so on. The forecasting results indicate that the proposed GHSA-FTS-LSSVM model effectively generates more accurate predictive results.

  17. A new load frequency control strategy for micro-grids with considering electrical vehicles

    DEFF Research Database (Denmark)

    Khooban, Mohammad-Hassan; Niknam, Taher; Blaabjerg, Frede

    2017-01-01

    sets (GT2FLS) and the Modified Harmony Search Algorithm (MHSA) technique, as a novel heuristic algorithm, to adaptively tune the proportional-integral (PI) controller for LFC in islanded MicroGrids (MGs). Although implementing general type-2 fuzzy systems is generally computationally cumbersome...... optimization algorithm to tune the scaling factors and the membership functions of general type-2 fuzzy PI (GT2FPI) controller and thereby to minimize the frequency deviations of the MG system against load disturbances more effectively. To evaluate the efficiency of the proposed controller, the obtained...... results are compared with those of the proportional integral derivative (PID), Fuzzy-PID (FPID), and Interval Type II fuzzy based PI (IT2FPI) controllers, which are the most recent methods applied in this respect. Simulation results demonstrate the perfection and efficacy of proposed controller....

  18. Reducing Gridlock on the Grid: Utility Trends in Managing Peak Electric Load through Residential Demand Response

    Science.gov (United States)

    McDonald, Betsy

    Utilities across the United States are piloting residential demand response programs to help manage peak electric demand. Using publicly available program evaluations, this thesis analyzes nine such programs to uncover and synthesize the range of program offerings, goals, enrollment strategies, and customer experiences. This review reveals that program participation, components, and results differ based on a variety of factors, including geographic characteristics, program goals, and implementation strategies. The diversity of program designs and evaluation findings suggests an underlying tension between the need to generate cost-effective program impacts and the desire to increase accessibility so that program benefits are not exclusive to certain segments of the population. For more significant and impactful engagement, program goals may need to shift. State level policy support could help shift program goals toward increasing program accessibility. Future research should explore creative strategies that target existing barriers and allow for more inclusive deployment.

  19. Stability of nonlinear load electric arc furnaces in the presence of reactive power sources

    Directory of Open Access Journals (Sweden)

    Pegah Sagha

    2014-04-01

    Full Text Available This paper first discusses about Electric arc.the model used in this paper is a dynamic model shown with a differential equation. Then, this model is placed with power system model which is considered as a thevenin equivalent model,and whole dynamical system is derived. With linearization around the work places, Jacobian Matrix of the system was extracted and the stability of equilibrium points specificed. Infollow, restricted equation to the central manifold for system intended is achieved and using that, possible events in the system the critical values of the bifurcation parameter is investigated. At the end, the analytical result is compared with the simulation results obtained with the help of Auto software. Finally, we will conclude that, using one type of the analytical method, one split of power system is characterized, but with using Auto software, all bifurcation are identified in the power system.

  20. Households under the impression of the energy turnaround. Development of electricity demand and load profiles; Die Haushalte im Zeichen der Energiewende. Entwicklung der Stromnachfrage und Lastprofile

    Energy Technology Data Exchange (ETDEWEB)

    Elsland, Rainer; Bossmann, Tobias; Gnann, Till; Wietschel, Martin [Fraunhofer-Institut fuer System- und Innovationsforschung (ISI), Karlsruhe (Germany); Hartel, Rupert; Fichtner, Wolf [Karlsruher Institut fuer Technologie (KIT), Karlsruhe (Germany). Inst. fuer Industriebetriebslehre und Industrielle Produktion (IIP)

    2013-01-15

    One of the central components of the energy turnaround is the improvement of energy efficiency. Households play a key role in this connection, not only due to their high potentials for saving energy and shifting loads, but also because of the growing importance of electricity as an energy carrier. This makes it interesting to explore how the continuing dissemination of efficient energy applications, electromobility and decentralised electricity production through photovoltaics will impact on load and electricity production profiles in the German household sector until the year 2040. The results show that with ambitious energy policy goals it will be possible to lower the electricity demand of households by 30%. However, this decrease could be more than undone by electromobility.

  1. Will we be heating with green electricity tomorrow? The large potential of load-variable private customer tariffs; Heizen wir kuenftig mit Oekostrom? Das grosse Potenzial lastvariabler Privatkundentarife

    Energy Technology Data Exchange (ETDEWEB)

    Zierdt, Tobias; Lang, Dirk [RWE Effizienz GmbH, Dortmund (Germany)

    2012-09-15

    Momentous changes loom ahead for Germany's energy supply system as a result of the energy turnaround. One central question is how load peaks from renewable energy plants can be conveniently accommodated on the demand side. Two research projects are currently being carried out to examine the acceptance of time-variable and load-variable tariffs for private households. First results show that using green electricity for heat generation is significantly more attractive for both customers and energy suppliers than using it to cover day-to-day electricity demand at a later time.

  2. Research and Application of Hybrid Forecasting Model Based on an Optimal Feature Selection System—A Case Study on Electrical Load Forecasting

    Directory of Open Access Journals (Sweden)

    Yunxuan Dong

    2017-04-01

    Full Text Available The process of modernizing smart grid prominently increases the complexity and uncertainty in scheduling and operation of power systems, and, in order to develop a more reliable, flexible, efficient and resilient grid, electrical load forecasting is not only an important key but is still a difficult and challenging task as well. In this paper, a short-term electrical load forecasting model, with a unit for feature learning named Pyramid System and recurrent neural networks, has been developed and it can effectively promote the stability and security of the power grid. Nine types of methods for feature learning are compared in this work to select the best one for learning target, and two criteria have been employed to evaluate the accuracy of the prediction intervals. Furthermore, an electrical load forecasting method based on recurrent neural networks has been formed to achieve the relational diagram of historical data, and, to be specific, the proposed techniques are applied to electrical load forecasting using the data collected from New South Wales, Australia. The simulation results show that the proposed hybrid models can not only satisfactorily approximate the actual value but they are also able to be effective tools in the planning of smart grids.

  3. Load Electricity Impact on Process of Dust Filtration%荷电对粉尘过滤过程影响的研究

    Institute of Scientific and Technical Information of China (English)

    詹亮亮; 卢锦奎; 翁煜彬

    2011-01-01

    Based on the requirement of technical development of electrical bag complex precipitator,tested load elec-tricity impact on process of dust filtration is made.The result shows that the load electricity makes an impact on the filtration pressure reduction of dust and filtration classification efficiency and particle could generate a certain accumulation phenomena in transportation.%针对电袋复合除尘器工程技术开发的需求,进行了粉尘荷电对过滤过程影响的测试实验。测试结果显示,荷电对粉尘的过滤压降等都会产生一定影响,并且在荷电条件下,粉尘颗粒在输送过程中会产生一定程度的聚并现象。

  4. Research of Electric Motor Multi-type Soft Start Control Mode Based on over-load Protection

    Directory of Open Access Journals (Sweden)

    Lina Liu

    2011-03-01

    Full Text Available This article in view of the question that the high power motor could not starting and stopping directly in the industry, proposed one kind of design based on PIC single chip high power motor soft start and intelligence protective devices, utilized real-time measurement and control method with the feature of synchronous sampling electric current spurt value inverse time lag protection, according to the load situation four starting and protection control soft start ways of the under intelligent protection controller were designed. Intelligent soft starter design principles based on PIC single chip is articulated. The hardware circuit design, software flow design and test data analysis are given in details. By producing in Zibo Galaxy high-technology development co., Ltd.,it shows that this smart soft starter has the characteristics which are flexible parameter setting, intuitive liquid crystal display, diverse starting way, precise current limiting protection, accurate protection of lack phase, low-cost, collecting soft start and running protection with a body's protection controller, are suitable specially for the starting and control of high power motor, so the protector has broad application prospects.

  5. Optimizing the Operation of Windfarms, Energy Storage and Flexible Loads in Modern Power Systems and Deregulated Electricity Markets

    Science.gov (United States)

    Dar, Zamiyad

    most turbines is quite close to 1/3 and yaw angle acts as the dominant optimization variable. In the next part of this dissertation, a system comprising of a windfarm and energy storage operating in real-time electricity markets is studied. An Energy-balancing Threshold Price (ETP) policy is proposed to maximize the revenue of a windfarm with on-site storage. We propose and analyze a scheme for a windfarm to store or sell energy based on a threshold price. The threshold price is calculated based on long-term distributions of the electricity price and wind power generation processes, and is chosen so as to balance the energy flows in and out of the storage-equipped windfarm. It is also shown mathematically that the proposed policy is optimal in terms of the long-term revenue generated. Comparing it with the optimal policy that has knowledge of the future, we observe that the revenue obtained by the proposed ETP policy is approximately 90% of the maximum attainable revenue at a storage capacity of 10-15 times the power rating of the windfarm. The intermittent nature of wind power is a hindrance to the efficient participation of windfarms in the day-ahead and forward electricity markets. In this regard, a flexible forward contract is proposed in this dissertation which allows the windfarms to enter into a forward contract with flexible load with an option to deviate from the contracted amount of power. Using such a flexible contract would allow the windfarms to supply more or less than the contracted amount of power in case of unexpected wind conditions or real-time prices. We also propose models for forecasting wind power and real-time electricity prices. The comparison between the proposed contracting framework and a simple fixed contract (currently existing in the market) for different levels of flexibility and load shows that there is a net gain in windfarm revenues, if the transaction price of the two contracts are set equal. Lastly, we present and analyze

  6. Appropriateness of a load-management agreement as the rate format for customer thermal storage: why a closeout sale on off-peak electricity should be adopted

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, S.H.

    1980-03-01

    This report demonstrates why a load-management agreement is the best rate format for customer thermal energy storage (TES) from electricity. The first section presents the basic operating and cost characteristics of TES systems as well as potential problems that affect rate setting. Then, the criteria for choosing a rate structure are put forth, and the various rate formats available are analyzed considering the above information. Finally, the means of achieving the maximum social benefits using a load-management agreement are explored.

  7. SSPC-based automatic management technology of electrical loads%基于SSPC的负载自动管理技术

    Institute of Scientific and Technical Information of China (English)

    刘晓羽

    2015-01-01

    随着飞机上用电设备的增多以及多电飞机概念的引入,常规配电方式及电网保护技术已经不能满足大规模用电负载的需要。电力电子技术的发展为自动配电技术提供了可能。基于固态功率控制器SSPC进行负载管理和电路保护,可根据负载控制方程自动管理负载。通过分布式配电技术实现负载就近取电,采用分层式总线布局代替传统控制线路,从而减轻了电网的重量。%With a greater amount of electrical equipments mounted on modern aircraft,especially with the concept introduc⁃tion of more electric aircraft,the conventional power distribution and grid protection technique can meet the requirements of mas⁃sive electricity load,but the power electronic technology provides possibilities for automatic power distribution. SSPC is used in load management and circuit protection system,which can automatically manage the electrical load according to the load control equations. The whole system weight can be reduced by the distributed power distribution technology to get power nearby and hierarchical bus architecture to replace the traditional control wires.

  8. Charging and discharging time control of electric vehicles for the purpose of load leveling; Fuka heijunka wo mokuteki to suru denki jidosha no juhoden jikan seigyo hosaku

    Energy Technology Data Exchange (ETDEWEB)

    Koyanagi, F.; Uriu, Y. [Seikei University, Tokyo (Japan)

    1998-05-01

    By ZEV regulation of the California government in 1990, not only the United States but also European countries and Japan are largely interested in replacing gasoline car by electric vehicle. Electric utilities expect that the electric vehicle improves the difference between the daytime and nighttime of a recent demand as a new market of electric power demand. There are some reports that indicates on the danger which generates the new peaks as the electric vehicles spread through the market in charging start hour. As the countermeasure for avoiding this problem, the authors propose that 1) inverse load flow by discharging of the contract private use EV is carried out as an energy shift in daytime, 2) the regional charging time shift method is introduced in the midnight charging time zone, in this paper. Therefore, the energy actual consumption of the automobile was investigated, and future demand was predicted by the mathematical consumption modeling. Especially, it is described a strategy of optimum introduction on scheme of effective electric vehicle for energy shift in section 2.2. And authors point out the necessity of market regulation for EV. 14 refs., 10 figs., 1 tab.

  9. Modeling of the effects of the electrical dynamics on the electromechanical response of a DEAP circular actuator with a mass-spring load

    Science.gov (United States)

    Rizzello, G.; Hodgins, M.; Naso, D.; York, A.; Seelecke, S.

    2015-09-01

    This paper presents a modeling approach of an actuator system based on a dielectric electro-active polymer (DEAP) circular membrane mechanically loaded with a mass and a linear spring. The motion is generated by the deformation of the membrane caused by the electrostatic compressive force between two compliant electrodes applied on the surface of the polymer. A mass and a linear spring are used to pre-load the membrane, allowing stroke in the out-of-plane direction. The development of mathematical models which accurately describe the nonlinear coupling between electrical and mechanical dynamics is a fundamental step in order to design model-based, high-precision position control algorithms operating in high-frequency regimes (up to 150 Hz). The knowledge of the nonlinear electrical dynamics of the actuator driving circuit can be exploited during the control system design in order to achieve desirable features, such as higher modeling accuracy for high-frequency actuation, self-sensing or control energy minimization. This work proposes a physical model of the DEAP actuator system which couples both electrical and mechanical dynamics occurring during the actuation process. By means of numerous experiments, it is shown that the model can be used to predict both actuator current and displacement, and therefore to increase the overall displacement prediction accuracy with respect to actuator models which neglect electrical behavior.

  10. Fatigue of Pb(Zr,Ti)O{sub 3} for different electrical-load forms; Ermuedung von Pb(Zr,Ti)O{sub 3} fuer unterschiedliche elektrische Belastungsformen

    Energy Technology Data Exchange (ETDEWEB)

    Balke, N.

    2006-07-01

    The present work deals with the effect of unipolar, sesquipolar, and bipolar cycling on material properties of Pb(Zr,Ti)O{sub 3} (PZT) ceramics and works out models to describe and explain the observed effects. In the case of bipolar fatigue the influence of different dopants and electrode material was observed. Additionally, the change of material parameters with applied dc voltages was investigated. The application of dc voltage and the unipolar cycling lead to the asymmetry and shifts of the ferroelectric hystereses. These changes can be explained by the separation of charge carriers which built up an offset field and offset polarisation in the material. In the case of bipolar fatigue two different scenarios can occur. If the electric contact between sample and electrode is bad or the grain boundaries are mechanically weak (microcrack formation), then drastic material changes in near electrode regions can be observed. The damaged region can be identified by colour changes and the microstructure in this region seem to be molten. The origin of the material damage is supposed to be decomposition of the sample, this is the formation of PbO due to electrical breakdowns at the microcracks and the accompanied temperature increase. Is the electric contact between sample and electrode good and no microcracks form, the sample is homogeneously fatigued and no material damage can be observed. In this case space charges are created in the material which influences the orientation of the polarisation by pinning of domains. PFM (Piezoresponse Force Microscopy) measurements show that the space charges must be positive. Also the local switching behaviour, which can be measured with PFM, influences the fatigue behaviour. A small distribution of coercive voltages leads to much less fatigue than a broader distribution. A broad distribution of coercive voltages is accompanied by more mechanical stress during switching and more cracking can occur. Besides the pure unipolar and pure

  11. Mechanical loading of knee articular cartilage induced by muscle contraction can be assessed by measuring electrical potentials at the surface of the knee.

    Science.gov (United States)

    Zhu, Lin; Buschmann, Michael D; Savard, Pierre

    2016-02-01

    Electroarthrography (EAG) consists of recording electrical potentials on the knee surface that originate from streaming potentials within articular cartilage while the joint is undergoing compressive loading. The aim was to investigate how the contraction of specific leg muscles affects the contact force of the knee joint and, in turn, the EAG values. For six normal subjects, voluntary isometric muscle contractions were repeatedly conducted to activate four leg muscle groups while the subject was lying on his back. Two EAG signals were recorded on the medial and lateral sides of the knee, as well as four EMG signals (gastrocnemius, hamstring, quadriceps, tensor fascia latae), and the signal from a force plate fixed against the foot according to the direction of the force. The EAG and force signals were very well correlated: the median of the correlation coefficients between an EAG signal and the corresponding force signal during each loading cycle was 0.91, and 86% of the correlation coefficients were statistically significant (pmuscle contraction was possible for the gastrocnemius and hamstring, but not always for the quadriceps and tensor fascia latae. Using the clinical loading protocol which consists of a one-legged stance, the quadriceps and hamstring EMGs showed minimal activity; loading cycles with increased EAG amplitude were associated with higher EMG activity from the gastrocnemius, which is involved in antero-posterior balance. These results document the role of the EAG as a "sensor" of the knee contact force and contribute to the development of clinical loading protocols with improved reproducibility.

  12. Bulk simulation for establishing the potential within the planning of load distribution and load shifting of an enhanced number of electrical consumers; Massensimulation zur Potenzialermittlung bei der Lastverlaufsplanung und -verlagerung einer hohen Anzahl elektrischer Verbraucher

    Energy Technology Data Exchange (ETDEWEB)

    Braunagel, Johannes; Schaefers, Hans; Renz, Wolfgang [Hochschule fuer Angewandte Wissenschaften Hamburg (Germany). Center for Demand Side Integration (C4DSI); Wiechmann, Holger [EnBW Vertrieb GmbH, Stuttgart (Germany)

    2012-07-01

    The shift to a renewable electricity production requires a reconstruction of the current electricity supply system. In a system with a big share of fluctuating electricity producers using renewable resources the production as well as the consumption has to be able to react flexibly to the current supply situation. This applies for the grid as a whole and in particular for parts of the distribution grid. In this context there is a demand for a robust, cheap and flexible control system which enables a utility to activate large numbers of consumers in the low power range. In this context the Center for Demand Side Integration at the University of Applied Sciences (HAW) Hamburg has been contracted by Energie Baden-Wuerttemberg (EnBW) (Germany's 3{sup rd} largest utility) to conduct a study on the development of control algorithms to control a large number (several tens of thousands) of decentralized applications. These algorithms were tested in an extensive modeling and simulation approach in which the behavior of the system was analyzed. The focus was on electric heating systems like domestic heat pumps and night storage heating. Thermal models of the applications and of domestic buildings were developed using Matlab/Simulink. Compiled as dynamic-link libraries these models were transferred to the multi-agent framework Jadex. This way it was possible to test the developed control algorithms on a network of up to 100,000 consumers. The mass simulation model was analyzed in terms of potentials, scale effects and reliability of load schedules and load shifting potentials. (orig.)

  13. Multi nodal load forecasting in electric power systems using a radial basis neural network; Previsao de carga multinodal em sistemas eletricos de potencia usando uma rede neural de base radial

    Energy Technology Data Exchange (ETDEWEB)

    Altran, A.B.; Lotufo, A.D.P.; Minussi, C.R. [Universidade Estadual Paulista Julio de Mesquita Filho (UNESP), Ilha Solteira, SP (Brazil). Dept. de Engenharia Eletrica], Emails: lealtran@yahoo.com.br, annadiva@dee.feis.unesp.br, minussi@dee.feis.unesp.br; Lopes, M.L.M. [Universidade Estadual Paulista Julio de Mesquita Filho (UNESP), Ilha Solteira, SP (Brazil). Dept. de Matematica], E-mail: mara@mat.feis.unesp.br

    2009-07-01

    This paper presents a methodology for electrical load forecasting, using radial base functions as activation function in artificial neural networks with the training by backpropagation algorithm. This methodology is applied to short term electrical load forecasting (24 h ahead). Therefore, results are presented analyzing the use of radial base functions substituting the sigmoid function as activation function in multilayer perceptron neural networks. However, the main contribution of this paper is the proposal of a new formulation of load forecasting dedicated to the forecasting in several points of the electrical network, as well as considering several types of users (residential, commercial, industrial). It deals with the MLF (Multimodal Load Forecasting), with the same processing time as the GLF (Global Load Forecasting). (author)

  14. Load Electricity Impact on Process of Dust Filtration%废弃啤酒酵母对重金属离子的吸附特性研究

    Institute of Scientific and Technical Information of China (English)

    张利祥; 孙志武; 吴宁; 戚秀云

    2011-01-01

    重金属污染问题已成为当今世界性的水污染治理难题,也是全球性的环境问题之一。实验采用发酵工业产生的废啤酒酵母为生物吸附材料,通过静态吸附实验,研究其对重金属离子Cu2+和Pb2+的吸附可行性及各种实验条件对吸附性能的影响,得出最佳工艺条件并对其动力学和热力学吸附过程进行分析。为下一步实验及扩大生产应用奠定了重要基础。%Based on the requirement of technical development of electrical bag complex precipitator, tested load electricity impact on process of dust filtration is made. The result shows that the load electricity makes an impact on the filtration pressure reduction of dust and filtration classification efficiency and particle could generate a certain accumulation phenomena in transportation.

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

    Energy Technology Data Exchange (ETDEWEB)

    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

  16. Regenerative electronic load for electric power sources tests using capacitive idling converter; Carga eletronica regenerativa para testes de fontes de energia eletrica utilizando conversor com capacitor flutuante

    Energy Technology Data Exchange (ETDEWEB)

    Vendrusculo, Edson Adriano

    1996-07-01

    The conventional method for testing power supplies, batteries, uninterruptible power supply and other sources of electric power uses resistors as load. This results in wasted heat and increases the equipment production cost. This work presents a Regenerative electronic Load to substitute those resistors. The basic topology is a capacitive idling Cuk converter. This converter allows to control independently the input current and permits to provide a sinusoidal output current. An appropriate gate command allows to have some soft-commutation without the use of any auxiliary circuit. The same converter, with input and output changed, can operate as a Power Supply with Input Power Factor Correction. The characteristics of soft-commutation and high efficiency are maintained. A simple high-efficiency transformer allows output isolation. All theoretical results are experimentally verified. (author)

  17. Dielectric properties of PLZT-x/65/35 (2≤x≤13 under mechanical stress, electric field and temperature loading

    Directory of Open Access Journals (Sweden)

    K. Pytel

    2013-01-01

    Full Text Available We investigated the effect of uniaxial pressure (0÷1000 bars applied parallely to the ac electric field on dielectric properties of PLZT-x/65/35 (2≤x≤13 ceramics. There was revealed a significant effect of the external stress on these properties. The application of uniaxial pressure leads to the change of the peak intensity of the electric permittivity (ϵ, of the frequency dispersion as well as of the dielectric hysteresis. The peak intensity ϵ becomes diffused/sharpened and shifts to a higher/lower temperatures with increasing the pressure. It was concluded that the application of uniaxial pressure induces similar effects as increasing the Ti ion concentration in PZT system. We interpreted our results based on the domain switching processes under the action of combined electromechanical loading.

  18. Nonintrusive electrical load identification and monitoring%非侵入式电力负荷的辨识和监测

    Institute of Scientific and Technical Information of China (English)

    朱德省; 尹建丰; 周琨荔

    2015-01-01

    本文提出了一种基于Mallat小波变换的电力负荷瞬态和动态轨迹综合辨识方法。其核心原理在于不同种电力负荷的动态和静态频域特征不尽相同;通过对负荷的电流和电压进行实时采样,并对其有功和无功功率进行实时计算,然后通过Mallat小波变换,将电压与电流、有功与无功功率的分层频谱轨迹特征图实时计算出。通过预先对每种负载的预学习和辨识,在实际使用中便可准确地对各类负载的使用及运行状态做出识别。当系统辨识的负载与预存的数据出现严重差异,可以推测出所接入的设备出现异常,或者有新的负载被接入;系统便可以启动相应的报警和应急处理机制,从而达到对电力负载的实时监控和管理的目的。%In this paper a Mallat wavelet transform based electrical load transient and steady state identification model is proposed. It is based on the fact that different electrical appliance has different transient and steady state spectrum signa-tures. Through load voltage and current sampling, active and reactive power calculation, and using Mallat wavelet trans-form FPGA, the trajectory patterns between voltage and current, between active power and reactive power for each wavelet output frequency segment could be obtained. This group of spectrum trajectory signatures for each type of load could be learnt in advance, so that the load can be identified when being used. When there is a large difference between the identified results and pre-learnt signature data, it means a load could be working abnormally or an alien device has been branched in. The system could then trigger warning and response mechanism, so as to achieve the objective of monitoring and controlling the connected electrical appliances.

  19. Electric drives

    CERN Document Server

    Boldea, Ion

    2005-01-01

    ENERGY CONVERSION IN ELECTRIC DRIVESElectric Drives: A DefinitionApplication Range of Electric DrivesEnergy Savings Pay Off RapidlyGlobal Energy Savings Through PEC DrivesMotor/Mechanical Load MatchMotion/Time Profile MatchLoad Dynamics and StabilityMultiquadrant OperationPerformance IndexesProblemsELECTRIC MOTORS FOR DRIVESElectric Drives: A Typical ConfigurationElectric Motors for DrivesDC Brush MotorsConventional AC MotorsPower Electronic Converter Dependent MotorsEnergy Conversion in Electric Motors/GeneratorsPOWER ELECTRONIC CONVERTERS (PECs) FOR DRIVESPower Electronic Switches (PESs)The

  20. Optimisation of load control

    Energy Technology Data Exchange (ETDEWEB)

    Koponen, P. [VTT Energy, Espoo (Finland)

    1998-08-01

    Electricity cannot be stored in large quantities. That is why the electricity supply and consumption are always almost equal in large power supply systems. If this balance were disturbed beyond stability, the system or a part of it would collapse until a new stable equilibrium is reached. The balance between supply and consumption is mainly maintained by controlling the power production, but also the electricity consumption or, in other words, the load is controlled. Controlling the load of the power supply system is important, if easily controllable power production capacity is limited. Temporary shortage of capacity causes high peaks in the energy price in the electricity market. Load control either reduces the electricity consumption during peak consumption and peak price or moves electricity consumption to some other time. The project Optimisation of Load Control is a part of the EDISON research program for distribution automation. The following areas were studied: Optimization of space heating and ventilation, when electricity price is time variable, load control model in power purchase optimization, optimization of direct load control sequences, interaction between load control optimization and power purchase optimization, literature on load control, optimization methods and field tests and response models of direct load control and the effects of the electricity market deregulation on load control. An overview of the main results is given in this chapter

  1. 短期电力负荷预测研究%Study on short term electric load forecasting

    Institute of Scientific and Technical Information of China (English)

    许祎; 王世芳

    2015-01-01

    Power system load forecasting through the historical data analysis,forecast future demand. In this paper,we use wavelet clustering to load data.Then we use the classical genetic algorithm,Elman neural network,wavelet neural network and combined intelligent algorithm to build the forecasting model.By comparing the simulation results of several short-term power load forecasting models,the hybrid intelligent algorithm can greatly enhance the accuracy and reliability of the load forecasting results,and has good application prospect.%电力系统负荷预测通过对历史数据分析,预测未来需求。本文先用小波聚类对数据进行负荷分类,再分别用经典的遗传算法、Elman神经网络算法、小波-神经网络算法和组合智能算法建立预测模型。通过比较以上几种短期电力负荷预测模型的仿真结果,验证了混合智能算法可以大大增强负荷预测结果的准确性和可靠性,具有良好的应用前景。

  2. Load Identification of Electric Locomotive Based on RBF Neural Network%基于RBF神经网络的电力机车负荷辨识

    Institute of Scientific and Technical Information of China (English)

    薛强; 蔡承才; 米海亭

    2016-01-01

    针对目前我国铁路机车型号较多,牵引网故障后机车类型辨识过程环节较多,实时性较差问题,本文研究了不同机车运行时电流有效值特点和谐波特性,提出了利用人工神经网络的方法来在线实现电力机车负荷辨识的方法,实验仿真结果表明,该方法可以准确快速的识别出运行于供电臂上的电力机车负荷类型,实时性好。%Aimed at the current problems of the railway locomotive in China, such as the models are too many, the links of locomotive type identification process after the failure of traction network are too much and the real-time problems are poor, this paper studies the characteristics of current effective value and harmonic of the operation of different locomotives. The method of using artificial neural network to realize load identification of electric locomotive is presented. Experimental results show that the proposed method can accurately and quickly identify the load type of electric locomotive running on the power supply arm, and the real-time performance is good.

  3. 46 CFR 169.689 - Demand loads.

    Science.gov (United States)

    2010-10-01

    ... Electrical Electrical Installations on Vessels of 100 Gross Tons and Over § 169.689 Demand loads. Demand loads must meet § 111.60-7 of this chapter except that smaller demand loads for motor feeders...

  4. Hierarchical Load Tracking Control of a Grid-connected Solid Oxide Fuel Cell for Maximum Electrical Efficiency Operation

    DEFF Research Database (Denmark)

    Li, Yonghui; Wu, Qiuwei; Zhu, Haiyu

    2015-01-01

    Based on the benchmark solid oxide fuel cell (SOFC) dynamic model for power system studies and the analysis of the SOFC operating conditions, the nonlinear programming (NLP) optimization method was used to determine the maximum electrical efficiency of the grid-connected SOFC subject...

  5. 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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  6. Load Flow Calculation of Electric Power System Based on MATLAB%基于MATLAB的电力系统潮流计算

    Institute of Scientific and Technical Information of China (English)

    毕永廷; 杨海波; 师秀凤

    2016-01-01

    通过应用MATLAB软件对给定的电力系统进行潮流计算。通过比较MATLAB程序、Simulink仿真和Matpower同一负荷变化情况下的潮流计算结果,结果满足系统要求,验证了三种方法的有效性。同时三种方法运算效率符合现在潮流计算的发展,为电网潮流计算开辟了新方向。%MATLAB is used to calculate the load flow of the electric system. By comparing the calculation results of MATLAB, Simulation and Matpower under the same load change, it is found that all the results meet the system requirements, thus the three methods' effectiveness is verified. And the calculation efficiency of the three methods conform to the development of modern load flow calculation, so these methods have opened up a new direction for power flow calculation.

  7. Improvement of quality and reliability of electric power supply using the supply transformer with under load tap change device

    Science.gov (United States)

    Grabko, Volodymyr V.; Balzan, Igor V.; Smolarz, Andrzej; Asambay, Azat

    2015-12-01

    On the base of the analysis of laws on voltage regulation by the supply transformers with the under load tap change device, the paper presents the modified regulation law, the use of which, unlike the known ones, allows to limit the number of tap changing of the supply transformer, which results in improvement of voltage quality of the consumers and the reliability of the under voltage tap change device operation.

  8. An In-Depth Look at Ground Source Heat Pumps and Other Electric Loads in Two GreenMax Homes

    Energy Technology Data Exchange (ETDEWEB)

    Puttagunta, Srikanth [Consortium for Advanced Residential Buildings (CARB), Norwalk, CT (United States); Shapiro, Carl [Consortium for Advanced Residential Buildings (CARB), Norwalk, CT (United States)

    2012-04-01

    Building America research team Consortium for Advanced Residential Buildings (CARB) partnered with WPPI Energy to answer key research questions on in-field performance of ground-source heat pumps and lighting, appliance, and miscellaneous loads (LAMELs) through extensive field monitoring at two WPPI GreenMax demonstration homes in Wisconsin. These two test home evaluations provided valuable data on the true in-field performance of various building mechanical systems and LAMELs.

  9. Modeling of plug-in electric vehicle travel patterns and charging load based on trip chain generation

    Science.gov (United States)

    Wang, Dai; Gao, Junyu; Li, Pan; Wang, Bin; Zhang, Cong; Saxena, Samveg

    2017-08-01

    Modeling PEV travel and charging behavior is the key to estimate the charging demand and further explore the potential of providing grid services. This paper presents a stochastic simulation methodology to generate itineraries and charging load profiles for a population of PEVs based on real-world vehicle driving data. In order to describe the sequence of daily travel activities, we use the trip chain model which contains the detailed information of each trip, namely start time, end time, trip distance, start location and end location. A trip chain generation method is developed based on the Naive Bayes model to generate a large number of trips which are temporally and spatially coupled. We apply the proposed methodology to investigate the multi-location charging loads in three different scenarios. Simulation results show that home charging can meet the energy demand of the majority of PEVs in an average condition. In addition, we calculate the lower bound of charging load peak on the premise of lowest charging cost. The results are instructive for the design and construction of charging facilities to avoid excessive infrastructure.

  10. Method to Estimate Long-term Change of Heat and Electric Power Daily Load Curves in Japan

    Science.gov (United States)

    Oda, Takuya; Akisawa, Atushi; Kashiwagi, Takao

    The rapid spread of CHP systems will put pressure on the regional power system to requiring an examination of the power and heat output of CHP systems. When considering the country-wide potential of the CHP system one should examine such system in coordination with the grid power system. It is essential to calculate the heat and power demand at end-use level. In the paper, annual heat and power demands of end-use sectors are forecast to the year 2025 based on 20 year data. Regression analysis is used. Estimated annual demands are divided into the seasonal hourly demands considering demand characteristics. Daily load curves of heat and power demands are determined for the Japanese end-use sectors, and the annual changes of such demands are shown by duration curves of heat to power ratios. Moreover, the grid power daily load curves are computed numerically from the estimated heat and power demands at manufacturing, residential and commercial sectors. Such load curves also consider self-generated power at manufacturing industry and own consumption of the grid power. Estimating heat and power demands allow for a joint analysis between the power system and the future phasing in of CHP systems.

  11. Calculation of cooling internal circuits loss of load curve in giant electric machines; Calculo da curva de perda de carga dos circuitos axiais internos de refrigeracao de maquinas eletricas gigantes

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Hilton Penha [Parana Univ., Curitiba, PR (Brazil). Dept. de Engenharia Mecanica. Dept. de Engenharia do Produto; Passos, Alex Sandro Barbosa [Parana Univ., Curitiba, PR (Brazil). Dept. de Engenharia Mecanica. Dept. de Pesquisa e Desenvolvimento do Produto

    2001-07-01

    This article describes a method for calculation of the loss of load curve for the ventilation axial circuits. The method assumes the ventilation circuit representation in a way similar to the electrical circuits. The great difficulty of circuit solution resides in the non linearity of the loss of load resistances and the equations relating the pressures and flows. The method is based on the association of the resistance curves of loss of load in a such way that, when the resistance curve of the total circuit loss of load is obtained, the blower operation point can be easily obtained and, consequently, the individual flows for each section of the circuit.

  12. The Structure-Dependent Electric Release and Enhanced Oxidation of Drug in Graphene Oxide-Based Nanocarrier Loaded with Anticancer Herbal Drug Berberine.

    Science.gov (United States)

    Yu, Danni; Ruan, Pan; Meng, Ziyuan; Zhou, Jianping

    2015-08-01

    The aim of the current investigation is to explore graphene oxide (GO) special electric and electrochemical properties in modulating and tuning drug delivery in tumor special environment of electrophysiology. The electric-sensitive drug release and redox behavior of GO-bearing berberine (Ber) was studied. Drug release in cell potential was applied in a designed electrode system: tumor environment was simulated at pH 6.2 with 0.1 V pulse voltage, whereas the normal was at pH 7.4 with 0.2 V. Quite different from the pH-depended profile, the electricity-triggered behavior indicated a high correlation with the carriers' structure: GO-based nanocomposite showed a burst release on its special "skin effect," whereas the PEGylated ones released slowly owing to the electroviscous effect of polymer. Cyclic voltammetry was used to investigate the redox behaviors of colloid PEGylated GO toward absorbed Ber in pH 5.8 and 7.2 solutions. After drug loading, the oxidation of Ber was enhanced in a neutral environment, whereas the enhancement of PEG-GO was in an acidic one, which means a possible increased susceptibility of their biotransformation in vivo. The studies designed in this work may help to establish a kind of carrier system for the sensitive delivery and metabolic regulation of drugs according to the different electrophysiological environment in tumor therapy. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association.

  13. THE NUMERICAL-FIELD ANALYSIS OF THE MAGNETIC FIELD AND THE ELECTRICAL QUANTITIES IN THE TURBOGENERATOR STATOR UNDER AUTONOMOUS UNBALANCED LOADING

    Directory of Open Access Journals (Sweden)

    V. I. Milykh

    2016-11-01

    Full Text Available Purpose. Assessing the impact of load asymmetry of turbogenerator (TG on the magnetic field distribution, on the electrical and energy processes in it based on the numerical-field analysis within the constraints regulated by the standards. Methodology. The calculation model of TG has been constructed on the method of symmetrical components of the three-phase current system. The formed asymmetric system of the currents is used for multi-position numerical calculations of rotating magnetic fields. The temporal functions of the electromagnetic quantities which are subjected to the harmonic analysis are obtained on this basis. Results. Test calculations are conducted on a three-phase 35 MW TG during his work under autonomous unbalanced loading. The analysis of the temporal functions of the magnetic induction at different points of the TG stator and also similar functions of the magnetic flux linkage, EMF phase stator windings and other variables have been executed. Originality. Problems of exploitation of turbo-generators under unbalanced loading are detected by the consideration of their electromagnetic system on the whole, but not their simplified local parts, as usual. It has been shown that the temporal functions of EMF of the phase stator windings under unbalanced loading significantly differ in shape from sine waves and from each other and contain a number of significant upper harmonics. It has been detected that the phase currents would contain not only the first but also significant upper harmonics under unbalanced loading. Practical value. Analysis of the work of TG under unbalanced loading showed the «top» level of problems of electromagnetic character. It has been established that the function of the magnetic induction at the fixed points of the magnetic system on the whole have been changed but not in principle. The temporal functions of EMF, and, hence, the voltage of the stator phase windings significantly differ in shape from sine

  14. Probabilistic Load Modeling of Electric Vehicle Charging Stations%电动汽车充电站的概率负荷建模

    Institute of Scientific and Technical Information of China (English)

    杨波; 陈卫; 明浩; 陈学有

    2014-01-01

    The load of electric vehicle(EV) charging stations has some stochastic features that make the study on the general load model difficult.In connection with three EV charging stations including battery swap stations,residential quarters charging stations and public charging stations,a probabilistic load modeling method is proposed based on charging modes, locations and trip characteristics.The probabilistic load models of three kinds of EV charging stations are obtained using Monte Carlo simulation and probability statistics analysis,by analyzing some vital factors of charging station load modeling in general. Moreover,optimized configuration schemes of three typical charging stations with best valley effect are obtained by using particle swarm algorithm optimization,and the validity and practicability of the proposed probabilistic load model are verified. This work is supported by National High Technology Research and Development Program of China (863 Program) (No.201 1AA05A109) and National Natural Science Foundation of China(No.5 1277085).%电动汽车充电站负荷的随机性特征,使相关建立具有通用性负荷模型的研究存在一定的困难,针对三类典型电动汽车充电站,即电池更换站、居民区充电站、公共场所充电站,提出了一种以充电方式、地理位置、出行特征为基础的概率负荷建模方法,通过全面研究充电站负荷建模的影响因素,采用蒙特卡洛模拟与概率统计分析规律相结合的方法综合建立三类典型充电站的概率负荷模型。在此基础上,运用粒子群算法优化得到了填谷效应最优的三类典型充电站的优化配置方案,验证了所建立的概率负荷模型的有效性和实用性。

  15. A Permutation Importance-Based Feature Selection Method for Short-Term Electricity Load Forecasting Using Random Forest

    Directory of Open Access Journals (Sweden)

    Nantian Huang

    2016-09-01

    Full Text Available The prediction accuracy of short-term load forecast (STLF depends on prediction model choice and feature selection result. In this paper, a novel random forest (RF-based feature selection method for STLF is proposed. First, 243 related features were extracted from historical load data and the time information of prediction points to form the original feature set. Subsequently, the original feature set was used to train an RF as the original model. After the training process, the prediction error of the original model on the test set was recorded and the permutation importance (PI value of each feature was obtained. Then, an improved sequential backward search method was used to select the optimal forecasting feature subset based on the PI value of each feature. Finally, the optimal forecasting feature subset was used to train a new RF model as the final prediction model. Experiments showed that the prediction accuracy of RF trained by the optimal forecasting feature subset was higher than that of the original model and comparative models based on support vector regression and artificial neural network.

  16. In-situ neutron diffraction study of cathode/electrolyte interactions under electrical load and elevated temperature

    Science.gov (United States)

    Tonus, F.; Skinner, S. J.

    2016-05-01

    Fuel cells are proposed as a future energy conversion technology that will reduce greenhouse gas emissions at the point of operation due to their ability to produce electrical energy from non-hydrocarbon fuel sources. The Solid Oxide Fuel Cell (SOFC) is amongst the most efficient fuel cell types, however, due to the high cell operating temperature cation diffusion occurs between the different components of the cell, resulting in rapid degradation of the power output. In this paper we investigate cation migration between the promising intermediate temperature-SOFC cathode La1-xSrxCo1-yFeyO3-δ (LSCF) and a fluorite type electrolyte Ce1-xPrxO2-δ (CPO). The crystallographic structure evolution and degradation of the materials were studied by neutron diffraction in-situ under pseudo-operating conditions, i.e. at 600 °C under air and under electrical polarisation. The lattice parameter and cation occupancy evolution were analysed by Rietveld refinement as a function of time and applied potential. The materials were found to be stable, as no impurity formation, lattice parameter or site occupancy evolution was observed during the experiment. However La migration prior to the experiment from LSCF to CPO was observed as well as B-site vacancies in LSCF.

  17. ETLS干扰力矩抑制及加载性能改善方法%Disturbance torque suppression and improved dynamic loading performance for electric torque loading simulator

    Institute of Scientific and Technical Information of China (English)

    赵文德; 唐琪; 张铭钧

    2016-01-01

    本文研制了ETLS的实验样机,建立了考虑加载系统摩擦非线性的ETLS综合数学模型。本文研究舵机系统位置扰动造成的多余力矩干扰问题,提出基于舵机系统输出角速度的前馈补偿控制进行抑制;考虑到加载系统的摩擦非线性问题,本文采用基于死区逆的方法进行补偿。接着,本文在力矩加载中存在幅值衰减和相位滞后问题上,采用基于最小均方差( least mean square error, LMSE)的幅相控制算法进行抑制以提高ETLS的加载性能,并提出基于Sigmoid函数变步长LMSE的幅相控制算法减小算法中收敛速度和稳态精度对步长需求相互矛盾,以提高算法整体改善。最后,通过仿真和实际实验,验证本文干扰力矩抑制和加载性能改善方法的有效性,在0.5 Hz和5 Hz频率下,基于本文方法的跟踪精度分别提高了87.0%和64.9%。%In this paper, an experimental prototype of electric torque loading simulator ( ETLS) is developed and the integrated mathematic model is built for ETLS along with friction nonlinearity of loading system. Based on the inves⁃tigation of the problem of surplus torque caused by position disturbance of the loaded system, this paper designs a feedforward compensation control method based on the output angular velocity of the loaded system. A compensation method is then developed on the basis of dead⁃inverse by considering friction nonlinearity of the loaded system. In addition, with respect to the problem of amplitude attenuation and phase lag of ETLS, this paper adopts an ampli⁃tude and phase control ( APC) algorithm based on the least mean square error ( LMSE) technique to improve the loading performance of ETLS. The APC algorithm based on the sigmoid function adaptive⁃step LMSE algorithm is subsequently proposed, with the aim of reducing the contradiction of step required by the convergence rate and steady precision, thereby improving the

  18. Effective properties of coated fibrous piezoelectric composites with spring-type interfaces under anti-plane mechanical and in-plane electrical loads

    Science.gov (United States)

    Shi, Yin; Wan, YongPing; Zhong, Zheng

    2016-10-01

    In this paper, we investigate the effective properties of three-phase (matrix/coating/fiber) cylindrical piezoelectric composites with imperfect interfaces under anti-plane mechanical and in-plane electrical loads. By using the electromechanically coupling spring-type interface model and the generalized self-consistent method (GSM), we analytically derived the effective electroelastic moduli. The present solutions include as special cases the three-phase cylindrical piezoelectric composites with perfect interfaces as well as the two-phase (matrix/fiber) case with imperfect or perfect interfaces. Selected calculations are graphically shown to demonstrate dependence of the effective moduli on the interfacial properties. The particular size-dependent characteristic due to the interfacial imperfection is also discussed.

  19. Simulink Based Study of the Load Characteristics of Electric Locomotive%基于SIMULINK的电力机车负荷特性研究

    Institute of Scientific and Technical Information of China (English)

    李欣然; 张广东; 朱湘友; 胡宗耀; 胡航帆

    2009-01-01

    By estimating the load structure of the locomotive, it has been proved that the characteristics of locomotive depend on traction loop.By studying the steady-state and transient characteristics of traction motor, a new method for the study of the pulsating-current traction motor and synthetic load characteristics of electric railway load has been introduced.The representative parameters of traction motor have been deducted in measured-based method and the results of simulation have proved the validity of the method.%通过研究典型电力机车的负荷构成特性,认为电力机车的负荷特性主要由牵引回路特性所决定.通过对系统运行于稳态和暂态两种状态下串励牵引电机特性的分析和数学模型的推导,得到脉流牵引电机的运行特性规律.利用总体测辨法,得到了能够描述牵引电机运行特性的负荷模型及参数.数字仿真结果也验证了该方法和结论的正确性和有效性,从而为研究电力机车的负荷特性及电气化铁路负荷的综合负荷特性提供了一种新的思路.

  20. A Comparative Study of Electric Load Curve Changes in an Urban Low-Voltage Substation in Spain during the Economic Crisis (2008–2013)

    Science.gov (United States)

    Lara-Santillán, Pedro M.; Mendoza-Villena, Montserrat; Fernández-Jiménez, L. Alfredo; Mañana-Canteli, Mario

    2014-01-01

    This paper presents a comparative study of the electricity consumption (EC) in an urban low-voltage substation before and during the economic crisis (2008–2013). This low-voltage substation supplies electric power to near 400 users. The EC was measured for an 11-year period (2002–2012) with a sampling time of 1 minute. The study described in the paper consists of detecting the changes produced in the load curves of this substation along the time due to changes in the behaviour of consumers. The EC was compared using representative curves per time period (precrisis and crisis). These representative curves were obtained after a computational process, which was based on a search for days with similar curves to the curve of a determined (base) date. This similitude was assessed by the proximity on the calendar, day of the week, daylight time, and outdoor temperature. The last selection parameter was the error between the nearest neighbour curves and the base date curve. The obtained representative curves were linearized to determine changes in their structure (maximum and minimum consumption values, duration of the daily time slot, etc.). The results primarily indicate an increase in the EC in the night slot during the summer months in the crisis period. PMID:24895677

  1. A comparative study of electric load curve changes in an urban low-voltage substation in Spain during the economic crisis (2008-2013).

    Science.gov (United States)

    Lara-Santillán, Pedro M; Mendoza-Villena, Montserrat; Fernández-Jiménez, L Alfredo; Mañana-Canteli, Mario

    2014-01-01

    This paper presents a comparative study of the electricity consumption (EC) in an urban low-voltage substation before and during the economic crisis (2008-2013). This low-voltage substation supplies electric power to near 400 users. The EC was measured for an 11-year period (2002-2012) with a sampling time of 1 minute. The study described in the paper consists of detecting the changes produced in the load curves of this substation along the time due to changes in the behaviour of consumers. The EC was compared using representative curves per time period (precrisis and crisis). These representative curves were obtained after a computational process, which was based on a search for days with similar curves to the curve of a determined (base) date. This similitude was assessed by the proximity on the calendar, day of the week, daylight time, and outdoor temperature. The last selection parameter was the error between the nearest neighbour curves and the base date curve. The obtained representative curves were linearized to determine changes in their structure (maximum and minimum consumption values, duration of the daily time slot, etc.). The results primarily indicate an increase in the EC in the night slot during the summer months in the crisis period.

  2. A Comparative Study of Electric Load Curve Changes in an Urban Low-Voltage Substation in Spain during the Economic Crisis (2008–2013

    Directory of Open Access Journals (Sweden)

    Pedro M. Lara-Santillán

    2014-01-01

    Full Text Available This paper presents a comparative study of the electricity consumption (EC in an urban low-voltage substation before and during the economic crisis (2008–2013. This low-voltage substation supplies electric power to near 400 users. The EC was measured for an 11-year period (2002–2012 with a sampling time of 1 minute. The study described in the paper consists of detecting the changes produced in the load curves of this substation along the time due to changes in the behaviour of consumers. The EC was compared using representative curves per time period (precrisis and crisis. These representative curves were obtained after a computational process, which was based on a search for days with similar curves to the curve of a determined (base date. This similitude was assessed by the proximity on the calendar, day of the week, daylight time, and outdoor temperature. The last selection parameter was the error between the nearest neighbour curves and the base date curve. The obtained representative curves were linearized to determine changes in their structure (maximum and minimum consumption values, duration of the daily time slot, etc.. The results primarily indicate an increase in the EC in the night slot during the summer months in the crisis period.

  3. Rechargeability and economic aspects of alkaline zinc-manganese dioxide cells for electrical storage and load leveling

    Energy Technology Data Exchange (ETDEWEB)

    Ingale, ND; Gallaway, JW; Nyce, M; Couzis, A; Banerjee, S

    2015-02-15

    Batteries based on manganese dioxide (MnO2) cathodes are good candidates for grid-scale electrical energy storage, as MnO2 is low-cost, relatively energy dense, safe, water-compatible, and non-toxic. Alkaline Zn-MnO2 cells, if cycled at reduced depth of discharge (DOD), have been found to achieve substantial cycle life with battery costs projected to be in the range of $100 to 150 per kWh (delivered). Commercialization of rechargeable Zn-MnO2 batteries has in the past been hampered due to poor cycle life. In view of this, the work reported here focuses on the long-term rechargeability of prismatic MnO2 cathodes at reduced DOD when exposed to the effects of Zn anodes and with no additives or specialty materials. Over 3000 cycles is shown to be obtainable at 10% DOD with energy efficiency >80%. The causes of capacity fade during long-term cycling are also investigated and appear to be mainly due to the formation of irreversible manganese oxides in the cathode. Analysis of the data indicates that capacity loss is rapid in the first 250 cycles, followed by a regime of stability that can last for thousands of cycles. A model has been developed that captures the behavior of the cells investigated using measured state of charge (SOC) data as input. An approximate economic analysis is also presented to evaluate the economic viability of Zn-MnO2 batteries based on the experiments reported here. (C) 2014 Elsevier B.V. All rights reserved.

  4. Research on Real-Time Optimization Strategy Based on Correlation of Household Electrical Load%基于家庭用电负荷关联度的实时优化策略

    Institute of Scientific and Technical Information of China (English)

    孙毅; 刘迪; 李彬; 李德智; 石坤

    2016-01-01

    针对家庭负荷在需求响应中巨大的不确定性,提出家电配合使用情况是家庭用户响应情况的重要影响因素之一,并提出家庭用电负荷关联度的概念。建立家庭用电负荷模型,设计基于家庭用电负荷关联度的实时更新的优化策略。通过Matlab 对算法模型在单个家庭用户以及多个家庭用户综合情况下进行仿真,验证了纳入家庭用电负荷关联度的实时优化策的有效性及优越性。%In view of huge uncertainty in demand response of household loads, this paper puts forward that cooperative use of household electrical appliance is an important factor affecting household user’s response, and proposes concept of household electricity load correlation. It builds household electricity load model and designs real time updated optimization strategy based on household electricity load correlation. Cases of single and multiple home users are simulated with a MATLAB model and effectiveness and superiority of the strategy are verified.

  5. Introduction effect of a load levelling system in an electric power system with a photovoltaic and wind system; Taiyoko/furyoku hatsuden wo donyu shita denryoku keito ni okeru fuka heijunka shisutemu no donyu koka

    Energy Technology Data Exchange (ETDEWEB)

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

    1998-12-05

    Introduction effect of load levelling system by a battery in an electric power system by a battery in an electric power system with a PV and wind system is investigated. Charge and discharge power of the battery are determined from a load curve and every hour data of PV and wind output. Annual cost of the power system is calculated from the generating power and the capacity of each source via the installed utility capacity and the capacity factor. It is found that (1) the battery system reduces the maximum demand and improves the load factor, (2) the cost effect of the battery system when introducing the PV system is higher than that when introducing the wind system. (author)

  6. Influence of frequency variation in the load behaviour in electric power systems; Influencia da variacao da frequencia no comportamento da carga dos sistemas eletricos de potencia

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira Sobrinho, Mauro de

    1994-11-01

    This work presents several models for the representation of load-frequency control systems and describes the main characteristics of the load. The composition of the load is described in details, divided by sectors. Finally, simulations of the load-frequency control system is performed. Conclusions are presented.

  7. daily nigerian nigerian nigerian peak load forec peak load forec ...

    African Journals Online (AJOL)

    User

    is generally needed for control and scheduling power system and also as inputs to load flo analysis .... Figure 1 Seasonal indices computing neural network ... Feedback paths are sometimes used. In applying a neural network to electric load ...

  8. Leveling of battery load and extension of battery life by serial connection of electric double layer capacitors with batteries for electric vehicles. Experimental results on the small model; Denki jidoshayo denchi to denki nijuso capacitor no chokuretsu setsuzoku ni yoru denchi futan no heijunka oyobi denchijumyo no enshinka. (kogata model ni yoru jikken seika). Kogata model ni yoru jikken seika

    Energy Technology Data Exchange (ETDEWEB)

    Takehara, J.; Okubo, N.; Miyaoka, K. [Chugoku Electric Power Co. Inc., Hiroshima (Japan)

    1996-10-25

    The load leveling method of batteries for electric vehicles was studied for extension of a battery life and mileage every charging. Under large load fluctuation conditions such as deceleration and acceleration, use of electric power sources other than battery for peek load at acceleration can improve a battery life, output power capacity and mileage every charging. Combination of effective recovery of regenerative power at deceleration with its discharge at acceleration is one of the effective methods. The electric double layer capacitors are serially connected with the batteries, regenerative power is charged only into the capacitors, and both voltages of the battery and capacitor are applied to a power circuit. Battery load is reduced by load on the capacitor. Until the capacitor is re-charged by regenerative power after full discharge, power is supplied only by battery through a diode. Capacitor power is used as effectively as possible until approaching considerably low voltage. As peak load of the battery is reduced by 30%, the mileage increases by 5.7%, and the battery cycle life becomes 1.5 times longer. 7 refs., 5 figs., 3 tabs.

  9. 聚合物膜上的微尺度金属导线在力电耦合作用下的屈曲行为%Buckling behavior of micro metal wire on polymer membrane under combined effect of electrical loading and mechanical loading

    Institute of Scientific and Technical Information of China (English)

    王庆华; 岸本哲; 谢惠民; 李艳杰; 吴丹

    2014-01-01

    The buckling behavior of a typical structure consisting of a micro constantan wire and a polymer membrane under coupled electrical-mechanical loading was studied. The phenomenon that the constantan wire delaminates from the polymer membrane was observed after unloading. The interfacial toughness of the constantan wire and the polymer membrane was estimated. Moreover, several new instability modes of the constantan wire could be further triggered based on the buckle-driven delamination. After electrical loading and tensile loading, the constantan wire was likely to fracture based on buckling. After electrical loading and compressive loading, the constantan wire was easily folded at the top of the buckling region. On the occasion, the constantan wire buckled towards the inside of the polymer membrane under electrical-compressive loading. The mechanisms of these instability modes were analyzed.%研究一种典型的微尺度康铜线/聚合物膜结构在力电耦合作用下的屈曲行为。根据卸载后康铜线从聚合物基底上屈曲的现象,评估康铜线与聚合物基底间的界面韧性。此外,力电耦合作用还会诱发新的失稳模态。在电载荷和拉伸载荷作用下,康铜线易在屈曲时发生断裂。在电载荷和压缩载荷作用下,康铜线易在屈曲区域的顶部发生折叠,偶尔还会向聚合物基底内部方向发生屈曲。分析了这些失稳模态的产生机理。

  10. Instruments. Climate protection of reduction of no-load losses in electric appliances and equipment; Klimaschutz durch Minderung von Leerlaufverlusten bei Elektrogeraeten. Instrumente

    Energy Technology Data Exchange (ETDEWEB)

    Rath, U.; Hellmann, R. [Ingenieurbuero fuer Energieberatung, Haustechnik und Oekologische Konzepte GbR (eboek), Tuebingen (Germany); Moehring-Hueser, W.; Wortmann, K.; Bregas, J. [Energiestiftung Schleswig-Holstein, Kiel (Germany); Mordziol, C. [Umweltbundesamt, Berlin (Germany)

    1999-12-01

    Two studies on the subject of 'Climate Protection through Reduction of No-load Losses in Electric Applicances and Equipment' have been performed on behalf of the German Federal Ministry for the Environment, Nature Conservation and Nuclear Safety and the German Federal Environmental Agency. The first study, carried out by the Tuebingen-based engineering bureau eboek, has been published in the Federal Environmental Agency's TEXTE series (Texte 45/97, 2{sup nd} edition, 1998). It was the starting point for a multitude of activities among them two information campaigns carried out in 1998 and 1999 that were funded by the Federal Ministry for the Environment and the German Section of the Friends of the Earth (BUND). The study also served as a basis for decisions taken by the German Bundestag and the Bundesrat (Council of Constituent States). The second study on the subject was carried out by the engineering bureau eboek and Energiestiftung Schleswig-Holstein. Building on the results obtained in the first study, it presents estimates of relevant data for the European Union and examines various approaches for possible measures to reduce no-load losses as to their suitability. The studies impressively show that effective climate protection can be achieved in all relevant sectors, and in many cases even save costs. The results are detailed below. (orig.) [German] Im Auftrag des Bundesministeriums fuer Umwelt, Naturschutz und Reaktorsicherheit sowie des Umweltbundesamtes wurden zwei Studien zum Thema: 'Klimaschutz durch Minderung von Leerlaufverlusten bei Elektrogeraeten' durchgefuehrt: Die erste, vom Ingenieurbuero fuer Energieberatung, Haustechnik und oekologische Konzepte (eboek), Tuebingen, earbeitete Studie wurde in der Reihe TEXTE des UBA veroeffentlicht (Texte 45/97, 2. Auflage 1998). Sie bildete den Ausgangspunkt fuer eine Vielzahl von Aktivitaeten, unter anderem zwei vom Bundesumweltministerium finanzierte und vom Bund fuer Umwelt und

  11. Let everybody think about energy problems (what to do with energy supply). Electric power storage as a trump to make load flat; Energy mondai wo minnade kangaeyo (energy kyokyu wo dosuruka). Fuka heijunka no kirifuda (denryoku chozo)

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, T. [Tokyo Electric Power Co., Inc. (Japan)

    1995-09-20

    Difference of electric power load between day and night has been growing due to increase of need for cooling in summer. In the case of Tokyo Electric Power Co., Ltd., the power maximum in a day exceeds 2-fold of the minimum. As a means of making load flat, power storage is a last resort to improve operation efficiency and suppress generation cost. Various technologies for electric power storage are overviewed and a sodium-sulfur (NaS) cell is introduced, whose practical application in near future is expected as a novel technology for power storage. Pumped storage generation has been put into practical use widely, sharing 10% of the overall capacity for generation facilities in Japan. However, since proper sites for its construction have been limited, compensating technologies, using electric cells, air compression, super-conduction and flywheels are in progress of research and development. There are three types of electric cells being under development; NaS, Zinc-bromine, redox flow cells. The NaS cell uses highly active electrodes of Na(+) and S(-), and {beta} alumina as electrolyte, which is neither electron-conductive nor self-discharging. 2 figs., 2 tabs.

  12. 电弧炉中废钢料的元素监测%Elemental monitoring of steel scrap loading an electrical arc furance

    Institute of Scientific and Technical Information of China (English)

    STURM Volker; EILERS Daniel; WERHEIT Patrick; CHIAROTTI Ugo; VOLPONI Vincenzo; DE MIRANDA Uggero; ZANI Marco; MAKOWE Joachim

    2012-01-01

    The use of laser-induced breakdown spectroscopy (LIBS) for scrap analysis has been evaluated for elemental monitoring of steel scrap loading an electrical arc furnace (EAF). A LIBS prototype was developed and installed during a field test above a pendulum conveying trough between the scrap charging area and the EAF, approx. 25 m from the EAF. The width and depth of the conveying trough filled with the scrap are approx. 2 m and 1 m, respectively. The average scrap velocity is adjusted to the EAF loading requirements within a range of 0. 3 to 5. 5 m/min, resulting in a scrap throughput of 100 tons per hour, typically. At the installation site, primarily, the detection of a high content of silicon in the low-alloy steel scrap is of interest for an improved control of the EAF. The on-line LIBS measurement showed the capability of detecting high silicon scrap in an industrial environment, although the developed prototype detected only a fraction of the scrap load surface due to the restricted measuring volume of 600 X 600 X 180 mm3. Increasing the measuring volume should further improve the performance in order to exploit it for charging/process control and management.%评估了激光诱导击穿光谱(LIBS)在废钢料分析中的使用,以用于电弧炉中废钢料的元素监测.开发了一个LIBS原型用于现场试验,并将其安装在位于废钢料填充区和电弧炉之间的钟摆式输送槽上.LIBS原型距离电弧炉大约25 m.废钢料填充的钟摆式输送槽的宽度和深度分别为大约2m和1 m.调整废钢料的平均速率在0.3~5.5 m/min的范围内,使之满足电弧炉的装填要求,从而使废钢料的生产能力达到100 t/h.在安装地点,低合金废钢料中高含量硅的检测基本上对电弧炉控制的改进很有帮助.由于测量体积受限在600×600×180mm3,研发的原型仅检测了一小部分的钢料表面.但是,在线LIBS测量还是显示了在工业环境下测定高硅废钢料样品的能力.为了拓展

  13. Realization of load balance technology in information system of Ningxia Electric Power Corporation%负载均衡技术在宁夏电力公司信息系统中的实现

    Institute of Scientific and Technical Information of China (English)

    李鹏

    2012-01-01

    针对宁夏电力公司信息化建设实践,分析了F5负载均衡设备对服务器的负载均衡的技术特点,提出了负载均衡设备的应用方案,结果表明:F5负载均衡设备在宁夏电力公司信息系统中的的合理使用,有效地提高了系统的运行效率,充分利用了现有资源,实现了信息系统的高可用性和高可靠性。%Aiming at the practice of information system construction in Ningxia Electric Power Corporation, analyzes the technical characteristics of F5 load balance equipment to balance the server' s load, brings forward the application schemes of load balance equipment. The results show that the rational application of F5 load balance equipment in information system of Ningxia Electric Power Corporation effectively improve operation efficiency of the system, make full use of the available resources, realizes the high usability and reliability of information system.

  14. Electrical Performance Influence of Loading on Inverted Long-wave Antenna%加载对垂挂式长波天线电气性能影响的研究

    Institute of Scientific and Technical Information of China (English)

    宫烨; 翟琦; 蒋宇中

    2016-01-01

    在借鉴机载长波天线、气球天线和COCO天线的基础上,建立三种形式的垂挂式长波发信天线模型,然后就顶容性加载和电感加载两个方面研究顶容线数量以及电感加载位置、加感量等对天线电气性能的影响.仿真结果表明:顶容性加载和电感加载均能使天线的阻抗特性和辐射性能得到改善,且电感加载能够间接缩短天线物理长度.这一研究结果对改善长波天线电气性能、缩短天线物理长度等具有重要的指导意义.%Based on the airborne long-wave antenna, kptoon and COCO antenna. The three types of inverted long-wave antenna model are established. The influence of capacitive loading and inductance loading, particularly of the top-line number, inductance loading position and quantity on antenna electrical performance, is fairly studied. Simulation shows that the capacitive loading and inductance loading could improve impedance characteristic and radiation property of the antenna, while the inductance loading shortening the physical length of antenna. This research result has a guiding significance in electrical performance improvement and physical length shortening of the antenna.

  15. Study on Plug-in Electric Vehicles Charging Load Calculating%电动汽车充电负荷计算方法

    Institute of Scientific and Technical Information of China (English)

    罗卓伟; 胡泽春; 宋永华; 杨霞; 占恺峤; 吴俊阳

    2011-01-01

    The policy and the development of plug-in electric vehicles(PEVs) in China are analyzed first.Then the charging modes and charging time of different kinds of PEVs' charging behaviors in China are proposed according to the field survey.The charging periods of different kinds of PEVs' charging behaviors are divided.The Monte Carlo simulation method is applied to determine the starting state of charge(SOC) and the initial charging point.With the charging methods(either on slow,regular,or fast mode) and initial charging point,together with the sampled starting SOC and charging needs of different PEVs' charging behaviors,the charging time can be calculated to get the charging curve.Based on the study,the future charging load in China is forecasted.The results indicate that the charging of PEVs will have significant impacts on the planning and operation of the power system.The huge difference between charging peak and off-peak provides a substantial potential to coordinate the charging of PEVs.%在研究中国电动汽车相关政策、发展趋势的基础上,基于调研结果,分析了不同类型电动汽车不同充电行为对应的充电方式及充电时段。根据不同类型电动汽车不同充电行为的充电功率,提出采用蒙特卡洛模拟抽取起始荷电状态、起始充电时间的电动汽车充电负荷计算方法。该方法将不同车辆的不同充电行为按充电需求进行分类,根据充电方式、起始荷电状态、充电需求、起始充电时间计算充电时间,获得充电负荷曲线。对中国未来电动汽车充电负荷水平进行了计算和分析。分析结果表明:随着中国电动汽车的发展,充电负荷将对电网的运行和规划带来较大的影响;充电负

  16. High Power Disk Loaded Guide Load

    Energy Technology Data Exchange (ETDEWEB)

    Farkas, Z.D.; /SLAC

    2006-02-22

    A method to design a matching section from a smooth guide to a disk-loaded guide, using a variation of broadband matching, [1, 2] is described. Using this method, we show how to design high power loads. The load consists of a disk-loaded coaxial guide operating in the TE{sub 01}-mode. We use this mode because it has no electric field terminating on a conductor, has no axial currents, and has no current at the cylinder-disk interface. A high power load design that has -35 dB reflection and a 200 MHz, -20 dB bandwidth, is presented. It is expected that it will carry the 600 MW output peak power of the pulse compression network. We use coaxial geometry and stainless steel material to increase the attenuation per cell.

  17. A comparison of four methods to evaluate the effect of a utility residential air-conditioner load control program on peak electricity use

    Energy Technology Data Exchange (ETDEWEB)

    Newsham, Guy R., E-mail: guy.newsham@nrc-cnrc.gc.ca [National Research Council Canada-Institute for Research in Construction, Building M24, 1200 Montreal Road, Ottawa, Ontario, K1A 0R6 (Canada); Birt, Benjamin J. [National Research Council Canada-Institute for Research in Construction, Building M24, 1200 Montreal Road, Ottawa, Ontario, K1A 0R6 (Canada); Rowlands, Ian H. [University of Waterloo, Ontario (Canada)

    2011-10-15

    We analyzed the peak load reductions due to a residential direct load control program for air-conditioners in southern Ontario in 2008. In this program, participant thermostats were increased by 2 deg. C for four hours on five event days. We used hourly, whole-house data for 195 participant households and 268 non-participant households, and four different methods of analysis ranging from simple spreadsheet-based comparisons of average loads on event days, to complex time-series regression. Average peak load reductions were 0.2-0.9 kWh/h per household, or 10-35%. However, there were large differences between event days and across event hours, and in results for the same event day/hour, with different analysis methods. There was also a wide range of load reductions between individual households, and only a minority of households contributed to any given event. Policy makers should be aware of how the choice of an analysis method may affect decisions regarding which demand-side management programs to support, and how they might be incentivized. We recommend greater use of time-series methods, although it might take time to become comfortable with their complexity. Further investigation of what type of households contribute most to aggregate load reductions would also help policy makers better target programs. - Highlights: > We analyzed peak load reductions due to residential a/c load control. > We used four methods, ranging from simple comparisons to time-series regression. > Average peak load reductions were 0.2-0.9 kW per household, varying by method. > We recommend a move towards time-series regression for future studies. > A minority of participant households contributed to a given load control event.

  18. Preseismic electric signals generated by critical stress loading of the lithosphere. A review of the type of signals obtained from a long lasted (1999 to 2012) experiment conducted in Greece

    CERN Document Server

    Thanassoulas, C; Verveniotis, G; Zymaris, N

    2012-01-01

    In this work a review is made of the various preseismic electric signals that have been observed before large EQs in Greece during the period of 1999 to 2012. The observed preseismic electric signals comply quite well with the theoretical ones that are expected to be generated by a large scale piezoelectric mechanism been activatsd at the focal area due to its excess stress-load. Preseismic electric signals of the total piezoelectric field, its first time derivative, its oscillation due to M1 and K1 tidal components have been observed by single monitoring sites during the actual 1999 to 2012 experiment in Greece. Moreover, the "strange attractor like" electric preseismic signal was detected by the simultaneously use of two distant monitoring sites. It is demonstrated that the preseismic electric signals can not only determine quite accurately a very short time window for the EQ occurrence and its epicentral location but the latter can be achieved without any prior knowledge of the geological, tectonic setting...

  19. 基于多因素加法模型的中期电力负荷预测%Multiple Factors Addictive Model for Mid-Term Electric Load Forecasting

    Institute of Scientific and Technical Information of China (English)

    翁金芳; 黄伟; 江育娥; 林劼

    2016-01-01

    提前准确预测所需电力负荷,做好电力规划是电力部门保证电力供应稳定不可或缺的重要环节.基于欧洲智能网络(EUNITE)竞赛电力数据和北美电力数据,提出一种多因素加法模型,进行中期电力预测.考虑到温度、假期、星期等因素对电力负荷产生不同的影响,拟合出这些因素与电力负荷之间的映射关系,相加得到电力负荷预测的函数.还比较了业界常用的7种不同的算法模型,使用6种不同指标对这些模型和多因素加法模型进行评估,实验结果发现,在这8种不同算法模型中,多因素加法模型有着更加精确的预测性能,运算速度比其他模型快,并且模型更加容易理解和解释.%Accuracy forecasting of electric load is important for power system to make plan. A Multiple Factors Addictive (MFA) model is proposed to predict mid-term electric load based on Europe (EUNITE) competition dataset and North American electric dataset. Firstly, MFA considers factors such as temperature, holiday, and week separately to fit functions for electric loads. And then all these fitted functions are added together to a unified function, which is used to make prediction of the electric load. Seven other state-of-art algorithms which are popular in the field are also used to make forecasting. The performances of prediction models are evaluated by using 6 different metrics. Compared with 7 other kinds of different models prediction results, MFA has the advantages of more accurate forecasting performance and faster operational speed, and is simple and easy to understand.

  20. Analysis and Modeling for Short- to Medium-Term Load Forecasting Using a Hybrid Manifold Learning Principal Component Model and Comparison with Classical Statistical Models (SARIMAX, Exponential Smoothing and Artificial Intelligence Models (ANN, SVM: The Case of Greek Electricity Market

    Directory of Open Access Journals (Sweden)

    George P. Papaioannou

    2016-08-01

    Full Text Available In this work we propose a new hybrid model, a combination of the manifold learning Principal Components (PC technique and the traditional multiple regression (PC-regression, for short and medium-term forecasting of daily, aggregated, day-ahead, electricity system-wide load in the Greek Electricity Market for the period 2004–2014. PC-regression is shown to effectively capture the intraday, intraweek and annual patterns of load. We compare our model with a number of classical statistical approaches (Holt-Winters exponential smoothing of its generalizations Error-Trend-Seasonal, ETS models, the Seasonal Autoregressive Moving Average with exogenous variables, Seasonal Autoregressive Integrated Moving Average with eXogenous (SARIMAX model as well as with the more sophisticated artificial intelligence models, Artificial Neural Networks (ANN and Support Vector Machines (SVM. Using a number of criteria for measuring the quality of the generated in-and out-of-sample forecasts, we have concluded that the forecasts of our hybrid model outperforms the ones generated by the other model, with the SARMAX model being the next best performing approach, giving comparable results. Our approach contributes to studies aimed at providing more accurate and reliable load forecasting, prerequisites for an efficient management of modern power systems.

  1. Household electricity demand profiles

    DEFF Research Database (Denmark)

    Marszal, Anna Joanna; Heiselberg, Per Kvols; Larsen, Olena Kalyanova

    2016-01-01

    Highlights •A 1-min resolution household electricity load model is presented. •Model adapts a bottom-up approach with single appliance as the main building block. •Load profiles are used to analyse the flexibility potential of household appliances. •Load profiles can be applied in other domains, e...

  2. Determination of the NOx loading of an automotive lean NOx trap by directly monitoring the electrical properties of the catalyst material itself.

    Science.gov (United States)

    Fremerey, Peter; Reiss, Sebastian; Geupel, Andrea; Fischerauer, Gerhard; Moos, Ralf

    2011-01-01

    Recently, it has been shown that the degree of loading of several types of automotive exhaust aftertreatment devices can be directly monitored in situ and in a contactless way by a microwave-based method. The goal of this study was to clarify whether this method can also be applied to NOx storage and reduction catalysts (lean NOx traps) in order to obtain further knowledge about the reactions occurring in the catalyst and to compare the results with those obtained by wirebound NOx loading sensors. It is shown that both methods are able to detect the different catalyst loading states. However, the sensitivity of the microwave-based method turned out to be small compared to that previously observed for other exhaust aftertreatment devices. This may limit the practical applicability of the microwave-based NOx loading detection in lean NOx traps.

  3. Determination of the NOx Loading of an Automotive Lean NOx Trap by Directly Monitoring the Electrical Properties of the Catalyst Material Itself

    Directory of Open Access Journals (Sweden)

    Ralf Moos

    2011-08-01

    Full Text Available Recently, it has been shown that the degree of loading of several types of automotive exhaust aftertreatment devices can be directly monitored in situ and in a contactless way by a microwave-based method. The goal of this study was to clarify whether this method can also be applied to NOx storage and reduction catalysts (lean NOx traps in order to obtain further knowledge about the reactions occurring in the catalyst and to compare the results with those obtained by wirebound NOx loading sensors. It is shown that both methods are able to detect the different catalyst loading states. However, the sensitivity of the microwave-based method turned out to be small compared to that previously observed for other exhaust aftertreatment devices. This may limit the practical applicability of the microwave-based NOx loading detection in lean NOx traps.

  4. 计及负荷率分档的峰谷分时电价定价模型%Pricing model of time-of-use electricity tariff considering customers classified by load factor

    Institute of Scientific and Technical Information of China (English)

    黄海涛; 吴洁晶; 顾丹珍; 蔚芳

    2016-01-01

    There is coordination problem between load factor price and peak-valley time-of-use price (TOU) of large and medium industrial and commercial users. Therefore, combining with the electricity power system and environment in China, this paper bases on the users demand and supply cost otherness to build the power consumption market segment and demand-price elastic model of load factor classification. Time-of-use electricity pricing model considering customers classified by load factor is settled applying the marginal cost pricing theory. The model adopts the method of hierarchical coordination optimization. The first layer applies the density clustering and two-part price theory to analyze the marginal electricity and capacity cost of each load factor block, and formulate the method for load factor classification and pricing average price for each one. The second layer takes the average price level of each block as constraint and cutting peak load to fill valley as the goal, then sets coordination optimization model of TOU tariff with load factor block based on the electric price elasticity matrix. This model coordinates multiple targets such as efficiency, fairness and peak load shifting. Its rationality and validity are validated by one case.%针对大中工商业用户负荷率电价与峰谷电价的配合问题,结合我国电力体制和电价制度环境,基于消费者需求和供电成本异质性,构造了负荷率分档用户的用电消费细分市场,建立了各档用户的边际供电成本模型及需求价格弹性模型。应用边际成本定价理论,构建了计及负荷率分档的峰谷分时电价模型。该模型采用分层协调优化的方法:第一层深入分析每一负荷率档位用户的边际电量成本和边际容量成本,应用密度聚类技术及两部制定价理论,建立了每一负荷率档位及其两部制平均电价水平的制定方法。第二层以各档平均电度电价水平为约束,以

  5. The Research of Electric Buses Power Plant Charging Optimization Based on Load Shifting%考虑削峰填谷的电动公交换电站充电优化研究

    Institute of Scientific and Technical Information of China (English)

    苗淼; 雷霞; 何建平; 李菲

    2015-01-01

    The electric buses which work in battery swapping mode achieve rapid growth in the field of public transportation. The normal operation of electric buses power plant is related to many factors, such as the replacement of the battery,battery charging and power load and so on. In order to improve the economy of power plant operation, the daily charging demands of electric buses are ana-lyzed and calculated. We set up the charging model of double objective optimization considering load shifting to minimum the charging costand reduce the load fluctuation. Lastly, the weight factor transformation method is utilized to analyze the example based on genetic algorithm and the simulation results show that the optimized charging cost can be saved 30 % with the sharpening peak effect.%采用换电模式的电动公交车在公共交通领域内发展迅速。电动公交换电站的正常运营与电池更换、充电和电网负荷等多方面因素有关。为提高电动公交换电站运营的经济性,首先分析和计算电动公交车的日换电量需求,然后以充电成本最小和减小负荷波动为目标建立考虑削峰填谷作用的双目标充电优化模型,最后利用遗传算法的权重系数变换法对实例进行求解。实例仿真计算结果表明,优化后的充电成本可节约30%,同时达到削峰填谷作用。

  6. 纯电动汽车空调系统负荷特性的试验研究%An Experimental Study on the Load Characteristics of A/C System in Pure Electric Vehicle

    Institute of Scientific and Technical Information of China (English)

    孙乐; 李红旗; 程睿; 马天琦

    2014-01-01

    鉴于纯电动汽车与普通汽车的空调系统负荷特性的较大差异,引入电动机室传入热的概念。在考虑电池包对空调冷负荷影响的基础上,对空调冷负荷进行了计算和测试,得到怠速工况和行驶工况下,从不同围护结构的瞬时得热量随时间的变化曲线。最后,比较分析了理论计算与测试的结果,为纯电动汽车空调系统负荷特性的研究提供参考。%In view of the big difference between pure electric vehicles and ordinary vehicles in load charac-teristics of A/C system, a concept of‘incoming heat from motor compartment’ is introduced. With consideration of the effects of battery pack on the cooling load of A/C system, both calculation and test on the cooling load of A/C system are conducted with the time-history curves of instantaneous heat acquired from different enclosure structures obtained in both idling and normal driving conditions. Finally the results of theoretical calculation and test data are compared and analyzed, providing references for further research on the load characteristics of A/C system in pure electric vehicles.

  7. Load forecasting of supermarket refrigeration

    DEFF Research Database (Denmark)

    Rasmussen, Lisa Buth; Bacher, Peder; Madsen, Henrik

    2016-01-01

    This paper presents a novel study of models for forecasting the electrical load for supermarket refrigeration. The data used for building the models consists of load measurements, local climate measurements and weather forecasts. The load measurements are from a supermarket located in a village...... in Denmark. Every hour the hourly electrical load for refrigeration is forecasted for the following 42 h. The forecast models are adaptive linear time series models. The model has two regimes; one for opening hours and one for closing hours, this is modeled by a regime switching model and two different...

  8. Load-shift incentives for household demand response: Evaluation of hourly dynamic pricing and rebate schemes in a wind-based electricity system

    DEFF Research Database (Denmark)

    Katz, Jonas; Møller Andersen, Frits; Morthorst, Poul Erik

    2016-01-01

    under scenarios with large shares of wind power in a Danish case study. Our results indicate strategies that could be favourable in ensuring high adoption of products and efficient response by households. We find that simple pricing schemes, though economically less efficient, could become important......Applying a partial equilibrium model of the electricity market we analyse effects of exposing household electricity customers to retail products with variable pricing. Both short-term and long-term effects of exposing customers to hourly spot market prices and a simpler rebate scheme are analysed...

  9. Load curve modelling of the residential segment electric power consumption applying a demand side energy management program; Modelagem da curva de carga das faixas de consumo de energia eletrica residencial a partir da aplicacao de um programa de gerenciamento de energia pelo lado da demanda

    Energy Technology Data Exchange (ETDEWEB)

    Rahde, Sergio Barbosa [Pontificia Univ. Catolica do Rio Grande do Sul, Porto Alegre (Brazil). Dept. de Engenharia Mecanica e Mecatronica]. E-mail: sergio@em.pucrs.br; Kaehler, Jose Wagner [Pontificia Univ. Catolica do Rio Grande do Sul, Porto Alegre (Brazil). Faculdade de Engenharia]. E-mail: kaehlerjw@pucrs.br

    2000-07-01

    The dissertation aims to offer a current vision on the use of electrical energy inside CEEE's newly defined area of operation. It also intends to propose different alternatives to set up a Demand Side Management (DSM) project to be carried out on the same market segment, through a Residential Load Management program. Starting from studies developed by DNAEE (the Brazilian federal government's agency for electrical energy), to establish the load curve characteristics, as well as from a research on electrical equipment ownership and electricity consumption habits, along with the contribution supplied by other utilities, especially in the US, an evaluation is offered, concerning several approaches to residential energy management, setting up conditions that simulate the residential segment's scenarios and their influence on the general system's load. (author)

  10. Dielectrically Loaded Biconical Antennas

    Science.gov (United States)

    Nusseibeh, Fouad Ahmed

    1995-01-01

    Biconical antennas are of great interest to those who deal with broadband applications including the transmission/reception of pulses. In particular, wide-angle conical antennas are an attractive choice in many applications including Electronic Support Measures (ESM) and the measurements of transient surface currents and charge densities on aircraft. Dielectric loading in the interior region of a conical antenna can be used to reduce the size of the antenna especially at low frequencies and/or for structural strength. Therefore, having an analytical solution for the input impedance and the frequency response is very helpful in optimizing the design and understanding the behavior of the antenna. From the quasi-analytical solution for the input impedance and the electric field of a wide-angle conical antenna, it can be seen that the dielectric loading in the antenna region improves the input impedance at low frequencies, but increases the number of resonance points and the magnitude of these peaks. When an inhomogeneous dielectric load is used, the magnitude of the resonance peaks is decreased (depending on the way the load is distributed), improving the input impedance of the antenna significantly. Introducing a dielectric load in the interior region of an electrically short receiving cone makes the antenna behave as an electrically longer antenna. However, this is not true for the case for electrical1y long antennas. For the case of pulse transmission, the dielectric load affects only the amplitude. Of course, if the dielectric fills the whole space, both transmitting and receiving antennas behave as electrically longer antennas.

  11. Influence of electric vehicle charging load distribution on power grid%考虑电动汽车充电负荷空间分布的系统特性分析

    Institute of Scientific and Technical Information of China (English)

    张明霞; 田立亭; 杨水丽; 胡娟; 侯朝勇

    2014-01-01

    Convenience and safety of electric vehicle is essential for electric vehicle industrialization. Since electric vehicle charging load is of random and aggregation, different charging position and power affect power system in different way. Integration of EV charging load will become one of the important problems for grid plan. Based on current charging modes, this paper investigates the voltage distribution and power loss of power system with random distribution and local concentration of charging load taken into account. The simulation indicates that the voltage and power loss are both closely related with the distribution of charging load. The EV charging station design and site selection principle are proposed.%电动汽车充电的便捷、安全是电动汽车产业化的必要保障。电动汽车充电负荷具有一定的随机性和集聚性,充电负荷接入电网的位置和容量不同,势必给电网带来不同的影响。如何适应电动汽车充电负荷的接入成为电网建设规划中面临的重点问题之一。基于现有的电动汽车充电方式的讨论,考虑电动汽车充电负荷随机分布和局部集中分布两种方式,通过仿真计算,详细研究了接入电网的电压和损耗特性,并对关键因素进行了分析。结果显示,接入电网的电压和损耗特性与充电负荷的分布密切相关。最后提出电动汽车充电站点设计和选址依据。

  12. A new combinational electrical load analysis method for demand side management%一种面向需求侧管理的用户负荷形态组合分析方法

    Institute of Scientific and Technical Information of China (English)

    黄宇腾; 侯芳; 周勤; 付博; 郭创新

    2013-01-01

    Traditional electrical load analysis methods have disadvantages on gaining the representative load profile of a single customer as well as evaluating similarity between the different load patterns. This paper proposes a new combinational load analysis method by using the density based clustering to gain the representative load profile of a single customer and clustering different customers into different clusters according to the cosine similarity function. After applying this method to a real power system’s data set, the result is compared with the one using traditional analysis method and the applications in demand side management (DSM) are discussed. The results show that this new method could effectively find the representative load profiles and recognize the different load profiles, and thus confirm the value of this method in DSM applications.%  提出了一种面向需求侧管理的用户负荷形态组合分析方法,改善了传统方法在单一用户典型负荷形态提取以及不同负荷形态相似性度量上的不足。该方法以密度聚类算法剔除单一用户异常日用电形态的影响,提取其典型负荷形态,再以余弦相似度度量不同用户典型负荷形态的相似波动特性,对用户进行分类。将该方法应用于实际电力负荷数据,将获得的用户分类结果与传统方法进行了比较,并以此为基础对负荷聚类在需求侧管理中的应用做了探讨。结果表明该方法能够有效地提取单一用户的典型负荷形态,并能够较好地度量不同负荷形态之间的相似波动特性,在需求侧管理中具有实用价值。

  13. 基于可避免购电成本的持续负荷转移成本有效性分析%Cost-effectiveness Analysis of Continuous Load Transfer Based on Avoidable Cost of Electricity Purchase

    Institute of Scientific and Technical Information of China (English)

    赵建华; 刘洋; 周飞; 曾鸣

    2012-01-01

    为使实时电价制度下电力供应紧缺时用户可通过可中断负荷合同自觉选择中断用电,避免一定的购电成本,建立了基于可避免成本的总购电成本模型,考虑了可再生能源投资标准约束和输配电容量约束对可避免成本估算的影响,提出逐时可避免成本影响下的持续负荷转移的成本有效性分析模型及年可避免购电成本的计算模型,并分析了持续负荷转移实现的成本效益.%When encountering the shortage of electricity supply,the user can consciously choose to interrupt the elec tricity through an interruptible load contract,which avoids the cost of power purchase in real-time pricing system. Based on the avoidable cost,this paper establishes a model of total cost of power purchase. Consdiering the impact of the standard constraints for renewable energy investment and capacity constraints on transmission and distribution on the estima tion of avoidable cost,it puts forward the cost-effectiveness analysis model for continuous load transfer under the influence of the avoidable cost and the calculation model for annual avoided electricity purchase cost is proposed. Finally,the cost benefit of continuous load transfer is analyzed.

  14. Design of the Electric Power Load Management System Based on ARM9%基于ARM9的电力负控终端系统的设计

    Institute of Scientific and Technical Information of China (English)

    马晓莉; 南权

    2011-01-01

    介绍了采用高端嵌入式单片机ARM9和嵌入式Linux操作系统构成的电力负荷终端系统,以及该系统的整体设计方案。终端利用嵌入式Linux操作系统为应用软件提供强大、稳定的资源环境,根据Q/GDW 374.1-2009《电力用户用电信息采集系统技术规范:专变采集终端技术规范》的要求,将智能电网管理终端多个任务划分为应用软件下执行任务多个线程,使得系统完成多任务的能力更强、稳定性更高%This paper introduces the Electric Power Load Management Terminals system which adopt the operating systems of ARM9 and Linux and the design of the system.The Electric Power Load Management Terminals have strong and steady application software depending on the Linux system.By the technique criterion Q/GDW 374.1-2009,the tasks of the smart electric network management terminals are resolved into several threads of the executive tasks under application softwares,thus improving the capability and stability with which the system implements multi-tasks

  15. Economic impacts of current harmonic from nonlinear loads on residential electricity distribution networks; Impactos economicos dos harmonicos de corrente das cargas nao lineares em redes eletricas de distribuicao residenciais

    Energy Technology Data Exchange (ETDEWEB)

    Duarte, Carlos Henrique

    2010-04-15

    To achieve more efficient energy use, power electronics systems (PES) may be employed. However, this introduce nonlinear loads into the system by generating undesired frequencies that are harmonic in relation to (multiples of) the fundamental frequency (60 Hz in Brazil). Consequently, devices using PES (power electronics systems) are more efficient but also contribute significantly to degradation of power quality. Besides this, both the conventional rules on design and operation of power systems and the usual premises followed in energy efficiency programs (without mentioning the electricity consumed by the devices themselves) consider the sinusoidal voltage and current waveforms at the fixed fundamental frequency (60 Hz in Brazil) of the power grid. Thus, analysis of electricity consumption reductions in energy efficiency programs that include the use of PES considers the reduction of kWh to the final consumer but not the additional losses caused by the increase in harmonic distortion. This dissertation investigates this problem by exploring a case study of the ownership and use of television sets (TV sets) to estimate the economic impacts of residential PES on a mainly residential electricity distribution system. (author)

  16. Load-shift incentives for household demand response: Evaluation of hourly dynamic pricing and rebate schemes in a wind-based electricity system

    DEFF Research Database (Denmark)

    Katz, Jonas; Møller Andersen, Frits; Morthorst, Poul Erik

    2016-01-01

    Applying a partial equilibrium model of the electricity market we analyse effects of exposing household electricity customers to retail products with variable pricing. Both short-term and long-term effects of exposing customers to hourly spot market prices and a simpler rebate scheme are analysed...... under scenarios with large shares of wind power in a Danish case study. Our results indicate strategies that could be favourable in ensuring high adoption of products and efficient response by households. We find that simple pricing schemes, though economically less efficient, could become important...... in an early phase to initialise the development of household demand response. At a later point, when long-term dynamics take effect, a larger effort should be made to shift consumers onto real-time rates, and an increased focus on overall adoption of variable pricing will be required. Another finding...

  17. Transformers in electrical energy engineering (part 1): Idle running and load; Transformatoren in der elektrischen Energietechnik (Teil 1): Leerlauf und Belastung

    Energy Technology Data Exchange (ETDEWEB)

    Kunze, G.

    1998-07-01

    Power transformers transform electric power from one state - voltage, current, phase - into another while maintaining the frequency and phase number. The process is described both theoretically and by examples. (orig.) [Deutsch] Leistungstransformatoren formen elektrische Energie einer Zustandsform - Spannung, Strom und Phasenlage - in die einer anderen um. Frequenz und Phasenzahl bleiben dabei erhalten. Wie das bei diesen ruhenden elektrischen Maschinen im Detail ablaeuft, wird zuerst theoretisch anvisiert und spaeter an praktischen Beispielen untermauert. (orig.)

  18. Electrical power distribution control methods, electrical energy demand monitoring methods, and power management devices

    Science.gov (United States)

    Chassin, David P.; Donnelly, Matthew K.; Dagle, Jeffery E.

    2006-12-12

    Electrical power distribution control methods, electrical energy demand monitoring methods, and power management devices are described. In one aspect, an electrical power distribution control method includes providing electrical energy from an electrical power distribution system, applying the electrical energy to a load, providing a plurality of different values for a threshold at a plurality of moments in time and corresponding to an electrical characteristic of the electrical energy, and adjusting an amount of the electrical energy applied to the load responsive to an electrical characteristic of the electrical energy triggering one of the values of the threshold at the respective moment in time.

  19. 一种特殊车载发电系统——驻车取力发电系统的研制%Development of Special Car Load Generating Electricity System Called Halt Car Taking Dint Generating Electricity

    Institute of Scientific and Technical Information of China (English)

    黄芳; 罗云行

    2011-01-01

    This paper introduced the development of a kind of special generating electricity the system called halt the car taking the dint generating electricity, mainly emphasized a few keys problem that must be resolved in research of manufacture process with the homologous solution technique or without the effect to driving abilities of car itself, added taking the dint equipment, designed taking the dint turns to control the system soon to guarantee the quality of the power supply of generating electricity system.%介绍了一种特殊车栽发电系统--驻车取力发电系统的研制,着重阐述了在研制过程中需要解决的几个关键问题和相应的解决技术,即在不影响汽车本身行驶性能的情况下加装取力装置、设计取力转速控制系统来保证发电系统的电源品质等.

  20. A New Combinational Electrical Load Analysis Method Based on Bilayer Clustering Analysis%一种基于双层聚类分析的负荷形态组合识别方法

    Institute of Scientific and Technical Information of China (English)

    王星华; 陈卓优; 彭显刚

    2016-01-01

    区别于传统用户用电行为分析方法,提出一种以聚类算法为基础的双层聚类分析方法。该方法结合给出的内、外层变随机设置为有目的选取初始聚类中心的选取规则,解决了聚类算法受初始聚类中心随机选取的影响,其收敛容易陷入局部最小化的问题。利用余弦相似度形态相似作为外层聚类的判据、欧式距离相近作为内层聚类的判据,对不需要经过归一化处理的用户用电轨迹向量进行分类。最后对某地区电力用户日负荷曲线进行算例分析,结果表明:双层聚类组合方法能把不同负荷形态及其大、小用户准确识别出来,实现了地区负荷形态的自动分类识别功能,证明了上述方法的有效性和优越性。%1Different from traditional electricity customer behavior analysis method, this paper presents a combinational load profile recognition method with two layers based on improved clustering algorithm. In order to overcome defect of traditional clustering algorithm, sensitive to initial conditions and usually leading to local minimum results, selection rules for two layers of initial cluster centers are proposed. It changes cluster center selection from random set to purposeful selection. On outer layer, it uses cosine similarity function as its performance evaluation index; on inner layer, Euclidean distance function is used as evaluation index. For the proposed method, it is not necessary to normalize load curve vector in analysis. This method is utilized to analyze calculation examples and daily electricity consumption curves of whole customers in a certain area. The method can automatically recognize cluster number, load categories and load distributions. The result verifies effectiveness and superiority of the proposed method.

  1. Load Measurements

    DEFF Research Database (Denmark)

    Kock, Carsten Weber; Vesth, Allan

    The report describes Load measurements carried out on a given wind turbine. The aim of the measurement program regarding the loads on the turbine is to verify the basic characteristics of the wind turbine and loads on the blades, the rotor and the tower, using [Ref 1], [Ref2] and [Ref 3]. Regarding...... the fatigue loads, the rotor, blades and tower moments are presented. The fatigue loads are evaluated using rainflow counting described in detail in Ref. [1]. The 1Hz equivalent load ranges are calculated at different wind speeds. All information regarding the instrumentation is collected in [ref 4] and [ref...

  2. 基于果蝇优化灰色神经网络的年电力负荷预测%Annual Electric Load Forecasting Based on Gray Neural Network with Fruit Fly Optimization Algorithm

    Institute of Scientific and Technical Information of China (English)

    傅军栋; 刘晶; 喻勇

    2015-01-01

    The accuracy of annual electric load forecasting plays an important role in economic and social benefits of electric power systems. The Gray Neural Network is an innovative computing approach, which has found wide application in reality. As a novel meta-heuristic and evolutionary algorithm, the fruit fly optimization algorithm has the advantages of being easy to understand and fast convergence to the global optimal solution. Therefore, to improve the forecasting performance, this paper proposes a GNN-based annual electric load forecasting model that uses FOA to automatically determine the appropriate values of the parameters for the GNN model to improve the forecasting accuracy and stability of the model. By taking the annual electricity consumption of China as an in⁃stance, the computational result shows that the GNN combined with FOA outperforms other alternative methods, namely the single GNN, the generalized regression neural network, the least squares support vector machine (LSSUM) and the regression model.%年电力负荷预测的准确性对电力系统的经济效益和社会效益具有重要作用。灰色神经网络(GNN)是一种创新的智能计算方法,在实际中广泛应用。尤其在预测问题方面具有极大的潜力。作为一种新型的启发式和进化算法,果蝇优化算法(FOA)具有易理解和快速收敛到全局最优解的优点。为提高预测性能,提出一种以GNN为基础的年电力负荷预测模型,使用FOA自动确定GNN模型的相应参数值,提高模型的稳定性和预测精度。通过利用中国的年用电量为实例,计算结果表明,GNN结合FOA(GNN-FOA)优于GNN ,广义回归神经网络(GRNN),最小二乘支持向量机(LSSVM)和回归模型等其他替代方法。

  3. Modelling and simulation of electrical energy systems through a complex systems approach using agent-based models. Case study: Under-frequency load shedding for refrigerators

    Energy Technology Data Exchange (ETDEWEB)

    Kremers, Enrique [Karlsruhe Institute of Technology (KIT), Karlsruhe (Germany). European Inst. for Energy Research (EIFER); Gonzalez de Durana, Jose Maria; Barambones, Oscar [Universidad del Pais Vasco, Vitoria (Spain). Escuela Universitaria de Ingenieria de Vitoria-Gasteiz

    2013-09-01

    One of the ways of studying complex systems is through modelling and simulation, which are used as tools to represent these systems in a virtual environment. Current advances in computing performance (which has been a major constraint in this field for some time) allow for the simulation these kinds of systems within reasonable time horizons. One of the tools for simulating complex systems is agent-based modelling. This individual-centric approach is based on autonomous entities that can interact with each other, thus modelling the system in a disaggregated way. Agent-based models can be coupled with other modelling methods, such as continuous models and discrete events, which can be embedded or run in parallel to the multi-agent system. When representing the electrical energy system in a systemic and multi-layered way, it is treated as a true socio-technical system, in which not only technical models are taken into account, but also socio-behavioural ones. In this work, a number of different models for the parts of an electrical system are presented, related to production, demand and storage. The models are intended to be as simple as possible in order to be simulated in an integrated framework representing the system as a whole. Furthermore, the models allow the inclusion of social behaviour and other, not purely engineering-related aspects of the system, which have to be considered from a complex point of view. (orig.)

  4. Influence of the intensity and loading time of direct current electric field on the directional migration of rat bone marrow mesenchymal stem cells.

    Science.gov (United States)

    Wang, Xiaoyu; Gao, Yuxuan; Shi, Haigang; Liu, Na; Zhang, Wei; Li, Hongbo

    2016-09-01

    Exogenic electric fields can effectively accelerate bone healing and remodeling through the enhanced migration of bone marrow mesenchymal stem cells (BMSCs) toward the injured area. This study aimed to determine the following: (1) the direction of rat BMSC (rBMSC) migration upon exposure to a direct current electric field (DCEF), (2) the optimal DCEF intensity and duration, and (3) the possible regulatory role of SDF-1/CXCR4 axis in rBMSC migration as induced by DCEF. Results showed that rBMSCs migrated to the positive electrode of the DCEF, and that the DCEF of 200 mV/mm for 4 h was found to be optimal in enhancing rBMSC migration. This DCEF strength and duration also upregulated the expression of osteoblastic genes, including ALP and OCN, and upregulated the expression of ALP and Runx2 proteins. Moreover, when CXCR4 was inhibited, rBMSC migration due to DCEF was partially blocked. These findings indicated that DCEF can effectively induce rBMSC migration. A DCEF of 200 mV/mm for 4 h was recommended because of its ability to promote rBMSC migration, proliferation, and osteogenic differentiation. The SDF-1/CXCR4 signaling pathway may play an important role in regulating the DCEF-induced migration of rBMSCs.

  5. 负荷管理系统在电力营销反窃电工作中的应用%On application of load management system in anti-electricity stealing management of power marketing

    Institute of Scientific and Technical Information of China (English)

    周惠民; 杨彩阁; 付红梅

    2012-01-01

    应用无线电力负荷管理系统进行计量异常监测来进行反窃电,该方法的优势在于既能及时发现线索,又能提供窃电证据,且相关技术成熟,操作起来形象直观、简单易行,为电力营销反窃电工作开辟了一条新途径。%Using Wireless Power Load Management System (WPLM) to have abnormal measure monitoring anti-eleetricity stealing management. The advantage of this method is both timely detecting clues, but also obtain stealing evidence, and related technologies is mature. It is visually simple to operate, which opened up a new way anti-electricity stealing management.

  6. Optimal Charge control of Electric Vehicles in Electricity Markets

    DEFF Research Database (Denmark)

    Lan, Tian; Hu, Junjie; Wu, Guang

    2011-01-01

    Environment constraints, petroleum scarcity, high price on fuel resources and recent advancements in battery technology have led to emergence of Electric Vehicles (EVs). As increasing numbers of EVs enter the electricity market, these extra loads may cause peak load and need to be properly...

  7. Development of experimental platform for airplane fly-by-wire and electric loading system%飞机电传操纵及模拟加载系统实验台开发

    Institute of Scientific and Technical Information of China (English)

    孟忱; 郝魁红; 何永勃

    2015-01-01

    Experimental platform for airplane fly‐by‐wire and electric loading system is designed to study the performance of airplane fly‐by‐wire control system and provide the experimental basis for the system . Hardware‐in‐the‐loop(HIL ) simulation of airplane control system can be completed .Students can adjust the aircraft attitude by a joystick of the experimental platform to simulate aircraft flight attitude adjustment .It can also do experiments such as permanent magnet synchronous motor system identification ,parameter debugging in PID control ,electric loading and the fault simulation of the four‐redundancy aircraft rudder .It can make students better understand the four‐redundancy EMA how to work .It also provide a platform for the research of fly‐by‐wire system .%为研究飞机电传操纵系统性能、给电传操纵系统设计提供实验依据,设计开发了飞机电传操纵及模拟加载系统实验台,实现全机飞控操纵系统半物理仿真。学生可以通过实验台操纵杆对飞机姿态进行调整,模拟飞机飞行过程中的姿态调整。并可完成永磁同步电机系统辨识、PID参数调试、电动加载模拟以及四余度方向舵故障模拟的实验,使学生更好熟悉四余度EM A机电作动器工作原理,为电传操纵系统的试验研究提供了平台。

  8. Load Measurements

    DEFF Research Database (Denmark)

    Vesth, Allan; Kock, Carsten Weber

    The report describes Load measurements carried out on a given wind turbine. The aim of the measurement program regarding the loads on the turbine is to verify the basic characteristics of the wind turbine and loads on the blades, the rotor and the tower, using [Ref 1], [Ref2] and [Ref 3]. Regardi...

  9. Load Measurements

    DEFF Research Database (Denmark)

    Kock, Carsten Weber; Vesth, Allan

    The report describes Load measurements carried out on a given wind turbine. The aim of the measurement program regarding the loads on the turbine is to verify the basic characteristics of the wind turbine and loads on the blades, the rotor and the tower, using [Ref 1], [Ref2] and [Ref 3]. Regarding...

  10. Long-term assessment of economic plug-in hybrid electric vehicle battery lifetime degradation management through near optimal fuel cell load sharing

    Science.gov (United States)

    Martel, François; Dubé, Yves; Kelouwani, Sousso; Jaguemont, Joris; Agbossou, Kodjo

    2016-06-01

    This work evaluates the performance of a plug-in hybrid electric vehicle (PHEV) energy management process that relies on the active management of the degradation of its energy carriers - in this scenario, a lithium-ion battery pack and a polymer electrolyte membrane fuel cell (PEMFC) - to produce a near economically-optimal vehicle operating profile over its entire useful lifetime. This solution is obtained through experimentally-supported PHEV models exploited by an optimal discrete dynamic programming (DDP) algorithm designed to efficiently process vehicle usage cycles over an extended timescale. Our results demonstrate the economic and component lifetime gains afforded by our strategy when compared with alternative rule-based PHEV energy management benchmarks.

  11. 200 km/h 八轴客运电力机车轴重转移分析%Axle - load Transfer Analysis of 200 km/h Eight - axle Passenger Electric Locomotive

    Institute of Scientific and Technical Information of China (English)

    吕凯凯; 王开云; 张志和

    2015-01-01

    An axle - load transfer model for a new 200 km/ h eight - axle passenger electric locomotive is established in this paper. Comparisons between calculation results obtained from the established model and that from the commercial dynamic software under the quasi - static condition are made. Some factors that affect the locomotive axle - load transfer are analyzed. The result shows that the axle - load of the first axle and second axle are reducing,while for the third axle and fourth axle they are increasing. The maxi-mum load - increasing ratio is happened to the fourth axle,which is 6. 28 percent,and the maximum load- reducing ratio is for the first axle,which is also 6. 28 percent. The calculation result is similar to that by using the commercial dynamic software where the difference is only about 0. 8 percent. Compared with the traction motor suspended on wheel - set,the traction motor suspended on frame could reduce the axle- load transfer by about 5. 77 percent. The optimal traction height for the 200 km/ h eight - axle passen-ger electric locomotive is 260 mm. Reducing the distance between motor front and rear suspension points can improve the adhesion weight usage of a locomotive.%针对一种新型的200 km/ h 八轴客运电力机车,建立了轴重转移计算模型。利用该模型计算其轴重转移,与动力学软件在准静态条件下的仿真结果进行对比,并分析影响机车轴重转移的因素。研究表明,该机车第一、二轴为减载,第三、四轴为增载,且第四轴增载最大,增载6.28%,第一轴减载最大,减载6.28%;模型计算结果与动力学软件仿真结果相差0.8%;机车牵引电机采用架悬方式能有效减小机车轴重转移,相比电机采用轴悬方式,机车轴重转移减小5.77%;该机车最优牵引点高度为260 mm;减小电机前后悬挂点之间的纵向跨距能有效提高机车黏着重量利用率。

  12. Load management using electric energy metering automation system%利用电能计量自动化系统开展负荷管理的探索

    Institute of Scientific and Technical Information of China (English)

    周勤兴; 郑日荣

    2014-01-01

    With the process of intelligent grid construction going along deeply in Shantou city,the power consumption of all the customers in this business district contained by electric energy metering automation management provides a very large amount of data and expanding the scope of application;therefore,it is neces-sary to manage the application function according to the load in the system.At the same time,combining with the work experience and the actual needs, the paper explores, develops and promotes the use of load management function reasonably so as to standardize customers demands and improve the efficiency of daily work.%介绍电能计量自动化系统在停电管理、配变重过载管理工作中的作用以及该系统在配网规划和业扩报装的辅助作用,阐述该系统利用其庞大的数据量,结合工作经验和实际需要,将其拓展应用到负荷管理工作中,规范了电力需求侧管理,提高了工作效率。

  13. Verification test for an electric vehicle using capacitor-battery series connection for battery load levelling; Denchi no fuka heijunka no tame no kyapashita to denchi no chokuretsu setsuzoku hoshiki wo saiyoshita denki jidosha no jissho shiken

    Energy Technology Data Exchange (ETDEWEB)

    Miyaoka, K.; Takehara, J.; Kato, S. [Chugoku Electric Power Co. Inc., Hiroshima (Japan)

    1998-03-25

    For the prolongation of the distance that an electric vehicle (EV) can cover on a single charge and of the service life of the EV battery unit, a system is developed, in which the battery unit and the capacitor unit are connected in series for the levelling-off of battery peak loads, and the system is tested aboard a running real vehicle. Installed on the real vehicle is a battery unit that is a series connection of 20 12V-38Ah seal-type lead-acid batteries, each battery consisting of two cells connected in parallel. Driving the vehicle is a DC brushless motor capable of a maximum operation of 9000rpm. Also installed is a capacitor unit that is a parallel connection of 40 2.3V-1800F capacitors, each capacitor consisting of two capacitors connected in parallel. Findings are described below. In a 0-400m acceleration test, 22.5 seconds is recorded with the capacitor unit in operation, meaning an improvement of 0.7 seconds. The maximum speed remains unchanged at 110km/h, which agrees with the pre-calculated value. Although the battery peak load reduction rate in a 15-mode drive pattern marks 23%, the distances covered on a single charge in this drive pattern turn out to be almost the same whether the capacitor unit is in operation or not. 3 refs., 15 figs., 3 tabs.

  14. 大数据背景下的充电站负荷预测方法%Load Forecasting Method for Electric Vehicle Charging Station Based on Big Data

    Institute of Scientific and Technical Information of China (English)

    黄小庆; 陈颉; 陈永新; 杨夯; 曹一家; 江磊

    2016-01-01

    The load forecast of electric vehicles (EVs) is the foundation of planning and scheduling of charging stations. Compared with the traditional method,the load forecast method under big data has the feature that the data to be forecast is quickly observable,real time,etc.Hence the need of the corresponding adjustments of the load forecast methods.This paper first analyzes the data demand for charging station planning and scheduling,and then the ways of main data acquisition.Based on volume,variety,velocity data,each EV”s start time,duration and location for charging,it will be possible to build the load model of a single EV.Furthermore,the total charging power of a charging station can be estimated by origin-destination(OD) flow statistics or adding up all the EV loads that are connected with its related transport line and node.Finally,a case study is given around the load forecast of EV station,and the load forecasting results from different load forecasting methods are compared.%电动汽车负荷预测是充电站规划及调度的研究基础。相比传统的负荷预测,大数据背景下的负荷预测具有待预测数据可快速观测的特点,此时负荷预测方法需要相应调整。首先分析了充电站负荷预测所需数据及主要数据来源。其次,针对单辆电动汽车,基于大量、快速更新、多种类的数据分析电动汽车的充电习惯,预测每一辆电动汽车的充电开始时间、持续时间和充电地点,获取单辆电动汽车的负荷模型。该模型综合考虑电池状态、出行时间、行驶路径与速度、充电偏好等信息。然后,面向任意充电站,对与其相关的路网节点与交通线路上的所有电动汽车负荷求和,估算该充电站的总充电功率。最后,进行实例仿真,并与传统方法下的充电负荷预测结果进行了对比。

  15. On Influence of Auto Electrical Load on Energy Saving and Emission Reduction%浅析汽车电气负荷对节能减排的影响

    Institute of Scientific and Technical Information of China (English)

    邵小进

    2014-01-01

    汽车给人们带来出行便捷的同时,也带来了一些负面影响,特别是日益严重的环境污染已经直接威胁人们的身心健康。本文从汽车电气负荷影响发动机油耗的角度来剖析驾驶汽车时合理使用汽车用电设备对降低油耗、减少污染的重要意义。%Automobile brings convenience for people's travel, but also brings many negative impacts at the same time, especially the increasingly serious environmental pollution which has direct threat to people's physical and mental health. This article analyzes the significance of rational use of automobile electrical equipment when driving a car in reducing fuel consumption and reducing pollution from the perspective of auto electrical load affecting the engine fuel consumption.

  16. Study on Charging Load Modeling and Coordinated Charging of Electric Vehicles Under Battery Swapping Modes%换电模式下电动汽车电池充电负荷建模与有序充电研究

    Institute of Scientific and Technical Information of China (English)

    罗卓伟; 胡泽春; 宋永华; 徐智威; 贾龙

    2012-01-01

    为了建立换电模式下电动汽车电池充电负荷及优化模型,对2种电动汽车换电模式即充换电模式和集中充电统一配送模式的结构、运营流程进行了分析.在满足用户换电需求的约束下,基于分时电价机制,提出考虑2种换电方式的以总充电费用最小为目标的第1阶段优化模型.第2阶段优化以第1阶段求取的最小充电费用为总充电费用的上限,以日负荷曲线波动最小为目标.以中国2020年充电负荷为例进行计算,对不同类型电动汽车采用不同的换电方式,并将换电模式与充电模式的充电负荷进行比较.计算结果表明,换电模式下无序充电情景峰荷较充电模式时增加较小,有序充电情景电网峰荷将不会增加,所提出的换电模式下有序充电模型能够有效减少充电费用及日负荷曲线波动.%To build the charging load calculation and optimization model under the battery swapping modes of electric vehicles (Evs), the structure and operation of two kinds of battery swapping modes, I.e. charging-swapping modes and centralized charging unified distribution modes, were analyzed. Then taken the constrains of satisfying the battery swapping needs of customers, the first stage coordinated charging formulation considering both the battery swap modes to minimize charging cost based on the time of use (TOU) power price mechanism were proposed. The peak load obtained from the first stage were set as the upper bound of the second stage optimization. In the second stage, the objective is to smooth the daily load curve fluctuation. Case studies calculate the charging loads of Evs in the year of 2020 in China, different kinds of battery swapping modes were matched for different kinds of Evs. The results were compared with those of the plug-in charging mode. The calculation results show that, the peak load under battery swapping modes increases less than the plug-in modes in the uncoordinated charging scenario

  17. Electric generators: Roesel

    Energy Technology Data Exchange (ETDEWEB)

    Segaser, C.L.

    1977-04-01

    A new and unique type of electrical generator is described that will provide constant frequency output (within 0.01% or better) regardless of rotational speed variations. It accomplishes this with no added bulk over conventional generators, and with excellent efficiency. The same principle that permits constant frequency output also provides the means for output voltage regulation with varying drive speed and/or varying load. Onsite power generation aspects of the Integrated Community Energy Systems (ICES) concept include the requirement to follow community electric loads and the possible use of internal combustion piston engines with waste heat recovery to drive electric generators. The diesel engine is a prime candidate from commercially available technologies for which part-load shaft efficiency is better at reduced speed than for constant-speed operation required by conventional AC generators. The unique characteristics of the Roesel generator allow prime mover speed to decrease with load and offer improved engine-generator system efficiency in ICES applications.

  18. Reliability impact of solar electric generation upon electric utility systems

    Science.gov (United States)

    Day, J. T.; Hobbs, W. J.

    1982-08-01

    The introduction of solar electric systems into an electric utility grid brings new considerations in the assessment of the utility's power supply reliability. This paper summarizes a methodology for estimating the reliability impact of solar electric technologies upon electric utilities for value assessment and planning purposes. Utility expansion and operating impacts are considered. Sample results from photovoltaic analysis show that solar electric plants can increase the reliable load-carrying capability of a utility system. However, the load-carrying capability of the incremental power tends to decrease, particularly at significant capacity penetration levels. Other factors influencing reliability impact are identified.

  19. Metamaterial Loadings for Waveguide Miniaturization

    CERN Document Server

    Odabasi, H

    2013-01-01

    We show that a rectangular metallic waveguide loaded with metamaterial elements consisting of electric-field coupled (ELC) resonators placed at the side walls can operate well below the cutoff frequency of the respective unloaded waveguide. The dispersion diagrams indicate that propagating modes in ELC-loaded waveguides are of forward-type for both TE and TM modes. We also study the dispersion diagram and transmission characteristics of rectangular metallic waveguides simultaneously loaded with ELCs and split ring resonators (SRRs). Such doubly-loaded waveguides can support both forward wave and backward waves, and provide independent control of the propagation characteristics for the respective modes.

  20. Multi-step constant-current charging method for electric vehicle, valve-regulated, lead/acid batteries during night time for load-levelling

    Energy Technology Data Exchange (ETDEWEB)

    Ikeya, Tomohiko; Mita, Yuichi; Ishihara, Kaoru [Central Research Inst. of Electric Power Industry, Tokyo (Japan); Sawada, Nobuyuki [Hokkaido Electric Power, Sapporo (Japan); Takagi, Sakae; Murakami, Jun-ichi [Tohoku Electric Power, Sendai (Japan); Kobayashi, Kazuyuki [Tokyo Electric Power, Yokohama (Japan); Sakabe, Tetsuya [Chubu Electric Power, Nagoya (Japan); Kousaka, Eiichi [Hokuriku Electric Power, Toyama (Japan); Yoshioka, Haruki [The Kansai Electric Power, Osaka (Japan); Kato, Satoru [The Chugoku Electric Power, Hiroshima (Japan); Yamashita, Masanori [Shikoku Research Inst., Takamatsu (Japan); Narisoko, Hayato [The Okinawa Electric Power, Naha (Japan); Nishiyama, Kazuo [The Central Electric Power Council, Tokyo (Japan); Adachi, Kazuyuki [Kyushu Electric Power, Fukuoka (Japan)

    1998-09-01

    For the popularization of electric vehicles (EVs), the conditions for charging EV batteries with available current patterns should allow complete charging in a short time, i.e., less than 5 to 8 h. Therefore, in this study, a new charging condition is investigated for the EV valve-regulated lead/acid battery system, which should allow complete charging of EV battery systems with multi-step constant currents in a much shorter time with longer cycle life and higher energy efficiency compared with two-step constant-current charging. Although a high magnitude of the first current in the two-step constant-current method prolongs cycle life by suppressing the softening of positive active material, too large a charging current magnitude degrades cells due to excess internal evolution of heat. A charging current magnitude of approximately 0.5 C is expected to prolong cycle life further. Three-step charging could also increase the magnitude of charging current in the first step without shortening cycle life. Four-or six-step constant-current methods could shorten the charging time to less than 5 h, as well as yield higher energy efficiency and enhanced cycle life of over 400 cycles compared with two-step charging with the first step current of 0.5 C. Investigation of the degradation mechanism of the batteries revealed that the conditions of multi-step constant-current charging suppressed softening of positive active material and sulfation of negative active material, but, unfortunately, advanced the corrosion of the grids in the positive plates. By adopting improved grids and cooling of the battery system, the multistep constant-current method may enhance the cycle life. (orig.)

  1. 电力用户侧大数据分析与并行负荷预测%Big Data Analysis and Parallel Load Forecasting of Electric Power User Side

    Institute of Scientific and Technical Information of China (English)

    王德文; 孙志伟

    2015-01-01

    With the development of smart grids, communication network and sensor technology, the electric power user side data is growing exponentially, more complexi, and gradually forms the big data of electric power user side. Now the traditional data analysis model can’t meet the demand of big data, so a new data analysis model aiming at analyzing and processing big data of power user side is urgently necessary. The source of the big data of electric power user side is analyzed in this paper. Those challenges facing data storage, availability, processing of the power user side are pointed out based on volume, variety and speed and other characteristics of the big data. Combining cloud computing technology, an analysis and processing platform of big data of electric power user side is given, which integrates smart meter data, SCADA systems data and various sensors data to be processed by MapReduce or Spark. A load forecasting method based on parallel random forests algorithm is proposed. Parallelization random forest algorithm is used to analyze data, such as load data, temperature, wind speed. The method shortens the time of load forecasting and improves random forests algorithm on data processing capability. Parallel load forecasting prototype system of electric power users side big data based on Hadoop is designed and implemented, including cluster management, data management, predictive classification algorithms library functions and so on. By using data sets of different sizes to do load forecasting experiment with parallelization random forest algorithm, the experiment results show that the prediction accuracy of the parallel random forest algorithm is significant higher than that of the decision tree. The prediction accuracy of different data sets is generally higher than the forecast accuracy of the decision tree, and applying the parallel random forest algorithm to analyze and processing big data is a better choice.%随着智能电网、通信网络技术和传

  2. Computer program for analysis of the electrical power consumption billing through the A-load and potency hyperboloid in a cold-storage slaughter house; Programa computacional para analise do faturamento do consumo de energia eletrica atraves do A-hiperboloide de carga e potencia em uma empresa frigorifica abatedora de bovinos

    Energy Technology Data Exchange (ETDEWEB)

    Cardim, Delcio [UNESP, Botucatu, SP (Brazil). Faculdade de Ciencias Agronomicas. Programa de Pos-Graduacao em Agronomia]. E-mail: delciocardim@uol.com.br; Gabriel, Luiz Roberto Almeida [UNESP, Presidente Prudente, SP (Brazil). Dept. de Matematica]. E-mail: gabriel@prudente.unesp.br

    2001-12-01

    The purpose of this work was to project and develop a computer program to analyze the billing of the electrical power consumption and the demand of active and reactive potency of a cold-storage slaughter house, by verifying their efficient and rational use of the electrical power. From the electrical standards of a enterprise, it is obtained,during peak and non-peak times, the potency factor (FP), the load factor (FC) and the average active consumption C{sub m}. Basing on the load factor (FC) and potency factor (FP) dta of slaughter house in a specific period, and by means of mathematical models, which govern the electrical consumption billing and demand of both the active and the reactive potency, it was possible to generate the surface denominated A-Load and Potency Hyperboloid. Then, the areas and volumes that were determined by this Hyperboloid were calculated. The results that were obtained through the volumes of the solids, determined by the hyperboloid and the areas of the regions determined by this surface, were used to analyze the situation of the considered slaughter house, regarding the electrical power consumption billing and demand of both the active and the reactive potency. Borland Delphi 5.0 Microsoft Windows environment was used of elaborating the compute program. (author)

  3. Electrical system design of loading test based on distributed control%基于分布式控制的某加载试验电气测控系统设计

    Institute of Scientific and Technical Information of China (English)

    任新胜; 王纪森; 赵雅菲

    2013-01-01

    According to the characteristics of the aircraft doors pneumatic loading tests,the measurement and control requirements of 21 loading channel are analyzed,the distributed control scheme is applied and the structure of the upper and lower computer is used; reasonable circuit design and Suitable PCI card are selected to complete the acquisition and Communication function of the lower computer; in the upper computer,supervisory control and data acquisition are realized through the LabWindows/CVI platform,Using the technology of multithreaded mechanism and the multimedia timer to ensure real-time requirements of the multi-channel distributed systems,and the electrical design in the ground simulated flight test works well and fully meet the requirements of the test in every index.%针对飞机舱门气动加载试验的特点,分析了21个加载通道的测控要求,应用分布式控制方案,采用上下住机结构;选用PCI板卡及合理的调理电路设计,完成了下住机的采集通信功能;上位机中,在labWindows/CVI平台下实现了了监督控制与数据采集,利用多线程机制及多媒体定时器技术,保证了多通道分布式系统中的实时性要求,该电气设计在地面模拟飞行试验中工作良好,充分满足了试验的各项指标要求.

  4. Impact of electric vehicle charging on distribution network load and coordinated control%电动汽车充电对配电网负荷的影响及有序控制研究

    Institute of Scientific and Technical Information of China (English)

    王建; 吴奎华; 刘志珍; 吴奎忠; 孙伟

    2013-01-01

    Aiming at the negative impact of large scale application of EV(Electric Vehicle) on the planning and operation of power system,a concept combining centralized optimal control and distributed optimal control is put forward and a coordinated control model is established.In order to realize the dynamic optimal control of EV charging,the centralized control takes the minimal network load fluctuation as its optimization objective while the distributed control takes the minimal deviation between the charging load within a dynamic time window and the result of centralized optimal control,the minimal charging cost and the prolonged battery life as its objectives.With the planning data of Shandong Grid as an example and the consideration of different factors such as charging time,charging pattern and penetration rate,the impact of EV charging on distribution network is analyzed for different scenarios,such as uncoordinated charging,time-of-use scheduled charging and coordinated charging,which verifies the validity and feasibility of the charging load model and the optimal control algorithm.%针对电动汽车规模化应用对电网规划运行带来的负面影响,提出采用集中式与分布式结合的优化控制理念,建立协调控制模型.集中式控制以电网负荷波动最小化作为优化目标,分布式控制以动态时间窗内充电需求与集中式优化控制结果之间的偏差、用户充电成本最小化以及延长电池寿命为优化目标,实现了电动汽车充放电的动态优化控制.以山东电网规划数据为例,考虑充电时间、充电模式、不同渗透率等因素,分析无序充电、时段控制充电、有序充电等多情景下电动汽车充电对配电网负荷的影响,结果验证了充电负荷模型和优化控制算法的有效性与可行性.

  5. Simulación de sistemas eléctricos con cargas no lineales y variantes en el tiempo Simulation of electric systems with non-linear and time-variant loads

    Directory of Open Access Journals (Sweden)

    William Carvajal Carreño

    2011-06-01

    of them and it permits to analyze linear and non linear systems in the time domain, linear systems in the frequency domain and mixed systems using the proposed hybrid method. The tool is intended to be a versatile and comprehensive computation instrument. Besides, it can be used in a straightforward way to analyze harmonic propagation in electrical networks. Examples from the literature used in electrical circuits, power systems, and power electronics courses are shown. Likewise, in order to analyze non-linear or time-varying loads, test systems were created as a benchmark for testing simulators of harmonics in electrical systems. Simulation results are analyzed and observations about the convergence features and algorithm stability of the proposed method are given. Due to the complexity and computational burden of hybrid analysis, we have selected element models, system models and suitable algorithms to guarantee that the solution is reasonable in terms of simulation time and computer resources.

  6. Load research manual. Volume 2. Fundamentals of implementing load research procedures

    Energy Technology Data Exchange (ETDEWEB)

    Brandenburg, L.; Clarkson, G.; Grund, Jr., C.; Leo, J.; Asbury, J.; Brandon-Brown, F.; Derderian, H.; Mueller, R.; Swaroop, R.

    1980-11-01

    This three-volume manual presents technical guidelines for electric utility load research. Special attention is given to issues raised by the load data reporting requirements of the Public Utility Regulatory Policies Act of 1978 and to problems faced by smaller utilities that are initiating load research programs. In Volumes 1 and 2, procedures are suggested for determining data requirements for load research, establishing the size and customer composition of a load survey sample, selecting and using equipment to record customer electricity usage, processing data tapes from the recording equipment, and analyzing the data. Statistical techniques used in customer sampling are discussed in detail. The costs of load research also are estimated, and ongoing load research programs at three utilities are described. The manual includes guides to load research literature and glossaries of load research and statistical terms.

  7. Iron load

    Directory of Open Access Journals (Sweden)

    Filippo Cassarà

    2013-03-01

    Full Text Available Recent research addressed the main role of hepcidin in the regulation of iron metabolism. However, while this mechanism could be relevant in causing iron load in Thalassemia Intermedia and Sickle-Cell Anemia, its role in Thalassemia Major (TM is marginal. This is mainly due to the high impact of transfusional requirement into the severe increase of body iron. Moreover, the damage of iron load may be worsened by infections, as HCV hepatitis, or liver and endocrinological damage. One of the most relevant associations was found between splenectomy and increase of risk for mortality due,probably, to more severe iron load. These issues suggest as morbidity and mortality of this group of patients they do not depend only by our ability in controlling heart damage but even in preventing or treating particular infections and complications. This finding is supported by the impairment of survival curves in patients with complications different from heart damage. However, because, during recent years different direct and indirect methods to detect iron overload in patients affected by secondary hemochromatosis have been implemented, our ability to maintain under control iron load is significantly improved. Anyway, the future in iron load management remains to be able to have an iron load map of our body for targeting chelation and other medical treatment according to the single organ damage.

  8. TE_01 High Power Disk Loaded Guide Load

    Energy Technology Data Exchange (ETDEWEB)

    Farkas, Z.D.; /SLAC

    2005-06-01

    A method to design a matching section from a smooth guide to a disk-loaded guide, using a variation of broadband matching, [1, 2] is described. Using this method, we show how to design high power loads, attenuators and filters. The load consists of a disk-loaded coaxial guide operating in the TE{sub 01}-mode. We use this mode because it has no electric field terminating on a conductor, has no axial currents, and has no current at the cylinder-disk interface. A high power load design that has -35 dB reflection and a 200 MHz, -20 dB bandwidth, is presented. It is expected that it will carry the 600 MW output peak power of the pulse compression network. We use coaxial geometry and stainless steel material to increase the attenuation per cell.

  9. multilevel buck converter for automotive electrical load

    African Journals Online (AJOL)

    user

    development of DCM based buck converter and its applications in the HEVs/EVs using ... The paper also highlights the implications of implementing a single stage buck converter, and ..... instance when the saw tooth signal within the internal.

  10. Beam loading

    CERN Document Server

    Gamp, Alexander

    2013-01-01

    We begin by giving a description of the radio-frequency generator-cavity-beam coupled system in terms of basic quantities. Taking beam loading and cavity detuning into account, expressions for the cavity impedance as seen by the generator and as seen by the beam are derived. Subsequently methods of beam-loading compensation by cavity detuning, radio-frequency feedback and feedforward are described. Examples of digital radio-frequency phase and amplitude control for the special case of superconducting cavities are also given. Finally, a dedicated phase loop for damping synchrotron oscillations is discussed.

  11. Knowledge-Based System to Support Plug Load Management

    Data.gov (United States)

    National Aeronautics and Space Administration — Electrical plug loads comprise an increasingly larger share of building energy consumption as improvements have been made to Heating, Ventilation, and Air...

  12. Carbohydrate Loading.

    Science.gov (United States)

    Csernus, Marilyn

    Carbohydrate loading is a frequently used technique to improve performance by altering an athlete's diet. The objective is to increase glycogen stored in muscles for use in prolonged strenuous exercise. For two to three days, the athlete consumes a diet that is low in carbohydrates and high in fat and protein while continuing to exercise and…

  13. Load sensor

    NARCIS (Netherlands)

    Van den Ende, D.; Almeida, P.M.R.; Dingemans, T.J.; Van der Zwaag, S.

    2007-01-01

    The invention relates to a load sensor comprising a polymer matrix and a piezo-ceramic material such as PZT, em not bedded in the polymer matrix, which together form a compos not ite, wherein the polymer matrix is a liquid crystalline resin, and wherein the piezo-ceramic material is a PZT powder for

  14. Carbohydrate Loading.

    Science.gov (United States)

    Csernus, Marilyn

    Carbohydrate loading is a frequently used technique to improve performance by altering an athlete's diet. The objective is to increase glycogen stored in muscles for use in prolonged strenuous exercise. For two to three days, the athlete consumes a diet that is low in carbohydrates and high in fat and protein while continuing to exercise and…

  15. Environmental Aspects of Load Management

    Energy Technology Data Exchange (ETDEWEB)

    Abaravicius, Juozas

    2004-02-01

    This study approaches load management from an environmental perspective. It identifies and discusses the possible environmental benefits of load management and evaluates their significance, primary focusing on CO{sub 2} emissions reduction. The analysis is carried out on two levels: national - the Swedish electricity market, and local - one electric utility in southern Sweden. Our results show the importance of considering the influence of site-specific or level-specific conditions on the environmental effects of load management. On the national level, load management measures can hardly provide significant environmental benefits, due to the high hydropower production in Sweden, which is the demand following production source. Emission reductions will rather be the result of energy efficiency measures, which will cut the load demand as well as the energy demand. However, when it comes to a local (utility) level, where load management is considered as an alternative to an installation of peak diesel power plant, the benefits are clear. It is demonstrated that significant CO{sub 2} emissions savings can be achieved due to avoided peak diesel power production.

  16. Performance of the tariffs of a single-phase electric energy meter, type electronic, operating with non-linear loads; Desempenho tarifario do medidor monofasico de energia eletrica do tipo eletronico operando com cargas nao-lineares

    Energy Technology Data Exchange (ETDEWEB)

    Santos, G.B.; Pinheiro Neto, D.; Lisita, L.R.; Machado, P.C.M.; Oliveira, J.V.M. [Universidade Federal de Goias (UFG), Goiania, GO (Brazil). Escola de Engenharia Eletrica e de Computacao], Emails: guilhermebsantos@gmail.com, daywes@gmail.com, lrlisi-ta@gmail.com, pcesar@eee.ufg.br, joao.eee@gmail.com

    2009-07-01

    This paper analyzes the behavior of a electronic meter of single-phase in the laboratory when it is subjected to a environment with linear loads and nonlinear loads kind residential and commercial. It differs from correlated studies mainly for making use of real loads encountered in day-to-day, rather than as sources of electronic loads how has been observed in the state of the art. The comparison of results is made based on high precision energy pattern developed by virtual instrumentation means.

  17. Projecting Electricity Demand in 2050

    Energy Technology Data Exchange (ETDEWEB)

    Hostick, Donna J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Belzer, David B. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hadley, Stanton W. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Markel, Tony [National Renewable Energy Lab. (NREL), Golden, CO (United States); Marnay, Chris [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Kintner-Meyer, Michael C. W. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2014-07-01

    This paper describes the development of end-use electricity projections and load curves that were developed for the Renewable Electricity (RE) Futures Study (hereafter RE Futures), which explored the prospect of higher percentages (30% - 90%) of total electricity generation that could be supplied by renewable sources in the United States. As input to RE Futures, two projections of electricity demand were produced representing reasonable upper and lower bounds of electricity demand out to 2050. The electric sector models used in RE Futures required underlying load profiles, so RE Futures also produced load profile data in two formats: 8760 hourly data for the year 2050 for the GridView model, and in 2-year increments for 17 time slices as input to the Regional Energy Deployment System (ReEDS) model. The process for developing demand projections and load profiles involved three steps: discussion regarding the scenario approach and general assumptions, literature reviews to determine readily available data, and development of the demand curves and load profiles.

  18. 基于用户意愿和出行规律的电动汽车充电负荷分配策略%A strategy for distribution of electric vehicles charging load based on user intention and trip rule

    Institute of Scientific and Technical Information of China (English)

    党杰; 汤奕; 宁佳; 伏祥运

    2015-01-01

    如何将大规模电动汽车有序充电控制需求在充分考虑充电个体需求和用户意愿的基础上进行合理分配是一个亟待解决的问题。首先提出电动汽车有序充电策略。其次,以电动汽车用户的意愿为前提,将每辆电动汽车电池充电次数最少作为目标,利用电动汽车的历史出行里程和电池实时状态确定电动汽车充电的加权系数,将电动汽车整体充电安排分解至每一辆电动汽车。最后,对所提方法进行了仿真验证。结果表明:考虑不同电动汽车使用特点和充电状态,约束每辆电动汽车的充电次数,可以在满足充电负荷要求的基础上安排电动汽车充电次序,同时减少每辆电动汽车充电次数,其分配原则具有合理性。%It is a serious problem that how to distribute large-scale electric vehicles coordinated charging load with the consideration of every single electric vehicle’s charging demands and user intention. Firstly, a coordinated charging strategy for electric vehicles is proposed. Secondly, based on meeting the intention of every electric vehicle user, aiming at minimizing charging times of electric vehicles, charging arrangements for electric vehicles are decomposed to every electric vehicle with the historical driving distances and battery real-time states made as the weighted coefficient. Finally, practical data are applied to the simulation. The results show that with the consideration of application characteristic, charging state and charging times of every electric vehicle, the charging strategy of every electric vehicle is arranged based on the satisfaction of the charging load required. At the same time, the charging times are reduced. The distribution principle proposed is reasonable.

  19. Electricity Customers

    Science.gov (United States)

    This page discusses key sectors and how they use electricity. Residential, commercial, and industrial customers each account for roughly one-third of the nation’s electricity use. The transportation sector also accounts for a small fraction of electricity.

  20. Model Predictive Load Scheduling Using Solar Power Forecasting

    OpenAIRE

    Habib, Abdulelah H.; Kleissl, Jan; de Callafon, Raymond A.

    2016-01-01

    In this paper a model is developed to solve the on/off scheduling of (non-linear) dynamic electric loads based on predictions of the power delivery of a (standalone) solar power source. Knowledge of variations in the solar power output is used to optimally select the timing and the combinations of a set of given electric loads, where each load has a desired dynamic power profile. The optimization exploits the desired power profiles of the electric loads in terms of dynamic power ramp up/down ...

  1. The influence of the reactive energy in the electric power sector planning and the need of consolidation of the hourly period for evaluation of the power factor of the loads; A influencia da energia eletrica reativa no planejamento do setor eletrico e a necessidade de consolidacao do periodo horario para avaliacao do fator de potencia das cargas

    Energy Technology Data Exchange (ETDEWEB)

    Andrade, Moacyr Trindade de Oliveira

    1993-07-01

    Among expectations of optimization of electric power systems and the national electric rating laws, there is the important factors of consumption and transmission of reactive energy which concerns the objectives of electric sector. Related to it, the DNAEE, ELETROBRAS and the concessionaires have been developing studies in order to optimize the electric system performance, and consequently the investments of concessionaires and consumers, reducing costs imposed to society due to the form of consumption and/or compensation of reactive loads. This work shows the evolution and consolidation of tariff studies and electric performance of the system, indicating the ways which attend the expectations os all segments of the society through a small adaptation of present regulations an rules related to reactive energy, making possible the system growing in supply by the minimum cost. The main objective of this work is to reinforce the real necessity of to remain intact all the new regulation of power factor, that has been consolidated by the DNAEE's document number 085/92 and your revaluation document number 613/93, including the interval of hourly integration for reactive energy at the determinate date and show the damages for the society caused by the postponement of this condition, that has been considerate in the document number 613/93, from April 1994 until April 1996, however keeping in 1994 the introduction of the new power factor reference of 0.92. (author)

  2. Electrical energy consumption control apparatuses and electrical energy consumption control methods

    Science.gov (United States)

    Hammerstrom, Donald J.

    2012-09-04

    Electrical energy consumption control apparatuses and electrical energy consumption control methods are described. According to one aspect, an electrical energy consumption control apparatus includes processing circuitry configured to receive a signal which is indicative of current of electrical energy which is consumed by a plurality of loads at a site, to compare the signal which is indicative of current of electrical energy which is consumed by the plurality of loads at the site with a desired substantially sinusoidal waveform of current of electrical energy which is received at the site from an electrical power system, and to use the comparison to control an amount of the electrical energy which is consumed by at least one of the loads of the site.

  3. Electricity Storage. Technology Brief

    Energy Technology Data Exchange (ETDEWEB)

    Simbolotti, G. [Italian National Agency for New Technologies, Energy and Sustainable Economic Development ENEA, Rome (Italy); Kempener, R. [International Renewable Energy Agency IRENA, Bonn (Germany)

    2012-04-15

    Electricity storage is a key technology for electricity systems with a high share of renewables as it allows electricity to be generated when renewable sources (i.e. wind, sunlight) are available and to be consumed on demand. It is expected that the increasing price of fossil fuels and peak-load electricity and the growing share of renewables will result in electricity storage to grow rapidly and become more cost effective. However, electricity storage is technically challenging because electricity can only be stored after conversion into other forms of energy, and this involves expensive equipment and energy losses. At present, the only commercial storage option is pumped hydro power where surplus electricity (e.g. electricity produced overnight by base-load coal or nuclear power) is used to pump water from a lower to an upper reservoir. The stored energy is then used to produce hydropower during daily high-demand periods. Pumped hydro plants are large-scale storage systems with a typical efficiency between 70% and 80%, which means that a quarter of the energy is lost in the process. Other storage technologies with different characteristics (i.e. storage process and capacity, conversion back to electricity and response to power demand, energy losses and costs) are currently in demonstration or pre-commercial stages and discussed in this brief report: Compressed air energy storage (CAES) systems, Flywheels; Electrical batteries; Supercapacitors; Superconducting magnetic storage; and Thermal energy storage. No single electricity storage technology scores high in all dimensions. The technology of choice often depends on the size of the system, the specific service, the electricity sources and the marginal cost of peak electricity. Pumped hydro currently accounts for 95% of the global storage capacity and still offers a considerable expansion potential but does not suit residential or small-size applications. CAES expansion is limited due to the lack of suitable

  4. Load testing circuit

    DEFF Research Database (Denmark)

    2009-01-01

    A load testing circuit a circuit tests the load impedance of a load connected to an amplifier. The load impedance includes a first terminal and a second terminal, the load testing circuit comprising a signal generator providing a test signal of a defined bandwidth to the first terminal of the load...

  5. 46 CFR 169.682 - Distribution and circuit loads.

    Science.gov (United States)

    2010-10-01

    ... Machinery and Electrical Electrical Installations Operating at Potentials of 50 Volts Or More on Vessels of... be installed; or (2) 50 watts per outlet. (b) Circuits supplying electrical discharge lamps must be computed using the ballast input current. (c) The branch circuit cables for motor and lighting loads...

  6. Usage monitoring of electrical devices in a smart home.

    Science.gov (United States)

    Rahimi, Saba; Chan, Adrian D C; Goubran, Rafik A

    2011-01-01

    Profiling the usage of electrical devices within a smart home can be used as a method for determining an occupant's activities of daily living. A nonintrusive load monitoring system monitors the electrical consumption at a single electrical source (e.g., main electric utility service entry) and the operating schedules of individual devices are determined by disaggregating the composite electrical consumption waveforms. An electrical device's load signature plays a key role in nonintrusive load monitoring systems. A load signature is the unique electrical behaviour of an individual device when it is in operation. This paper proposes a feature-based model, using the real power and reactive power as features for describing the load signatures of individual devices. Experimental results for single device recognition for 7 devices show that the proposed approach can achieve 100% classification accuracy with discriminant analysis using Mahalanobis distances.

  7. Structure and algorithm of hybrid control in cerebella model articulation controller for electric loading system%新型小脑模型关联控制器复合控制在电动加载系统中的结构及算法

    Institute of Scientific and Technical Information of China (English)

    杨波,; 王哲

    2011-01-01

    在电动加载系统中,多余力矩强扰动和其他非线性因素直接影响力矩跟踪精度,传统的控制方法很难得到满意的控制效果.本文分析了电动加载系统中多余力矩产生机理,提出了一种新型小脑模型关联控制器(CMAC)复合控制策略,并对其结构及算法进行了研究.在控制结构上以系统的指令输入和实际输出作为CMAC的激励信号,采用误差作为训练信号,并根据激励信号的特点,提出了非均匀量化的思想.不同于常规CMAC的误差平均分配,新型CMAC根据高斯权重系数来分配误差.动态仿真结果表明,该方法有效抑制了加载系统的多余力矩及摩擦等非线性因素干扰,提高了电动加载系统的控制精度,增强了系统的稳定性.%The disturbance of surplus torque and the nonlinearity deteriorate the precision of torque tracking in the electric loading system. This undesired effect can not be removed satisfactorily by the conventional control. To deal with this problem, after analyzing the effect of surplus torque on the electric loading system, we propose a hybrid control based on the novel cerebella model articulation controller(CMAC) and investigate its structure and algorithm. This control adopts the desired output and the actual output of the electric loading system as the incentive signals of CMAC, and treats the error between the desired output and the actual output as the training signal for the CMAC structure. A non-uniform quantization scheme is then proposed according to the characteristics of the incentive signals. In the conventional CMAC, errors are equally distributed into memory cells; while the novel CMAC allocates errors according to the Gaussian weighting coefficients. Simulation results show that the proposed hybrid controller effectively suppresses the disturbance of surplus torque and the nonlinearity such as friction, improves the control precision of the electric loading system and enhances the

  8. Loads and loads and loads: The influence of prospective load, retrospective load, and ongoing task load in prospective memory

    Directory of Open Access Journals (Sweden)

    Beat eMeier

    2015-06-01

    Full Text Available In prospective memory tasks different kinds of load can occur. Adding a prospective memory task can impose a load on ongoing task performance. Adding ongoing task load can affect prospective memory performance. The existence of multiple target events increases prospective load and adding complexity to the to-be-remembered action increases retrospective load. In two experiments, we systematically examined the effects of these different types of load on prospective memory performance. Results showed an effect of prospective load on costs in the ongoing task for categorical targets (Experiment 2, but not for specific targets (Experiment 1. Retrospective load and ongoing task load both affected remembering the retrospective component of the prospective memory task. We suggest that prospective load can enhance costs in the ongoing task due to additional monitoring requirements. Retrospective load and ongoing task load seem to impact the division of resources between the ongoing task and retrieval of the retrospective component, which may affect disengagement from the ongoing task. In general, the results demonstrate that the different types of load affect prospective memory differentially.

  9. Marine electrical practice

    CERN Document Server

    Watson, G O

    1991-01-01

    Marine Engineering Series: Marine Electrical Practice, Sixth Edition focuses on changes in the marine industry, including the application of programmable electronic systems, generators, and motors. The publication first ponders on insulation and temperature ratings of equipment, protection and discrimination, and AC generators. Discussions focus on construction, shaft-drive generators, effect of unbalanced loading, subtransient and transient reactance, protection discrimination, fault current, measurement of ambient air temperature, and basis of machine ratings. The text then examines AC switc

  10. Transmission grid requirements with scattered and flutuating renewable electricity sources

    DEFF Research Database (Denmark)

    Østergaard, Poul Alberg

    2002-01-01

    Denmark is in a situation with many scattered sources of electricity, that are not controlled by the central load dispatch. At the same time, Denmark is being used as an electricity transit corridor between Norway/Sweden and Germany. Through energy systems analyses and load-flow analyses, it is d......Denmark is in a situation with many scattered sources of electricity, that are not controlled by the central load dispatch. At the same time, Denmark is being used as an electricity transit corridor between Norway/Sweden and Germany. Through energy systems analyses and load-flow analyses...

  11. Short term load forecasting of anomalous load using hybrid soft computing methods

    Science.gov (United States)

    Rasyid, S. A.; Abdullah, A. G.; Mulyadi, Y.

    2016-04-01

    Load forecast accuracy will have an impact on the generation cost is more economical. The use of electrical energy by consumers on holiday, show the tendency of the load patterns are not identical, it is different from the pattern of the load on a normal day. It is then defined as a anomalous load. In this paper, the method of hybrid ANN-Particle Swarm proposed to improve the accuracy of anomalous load forecasting that often occur on holidays. The proposed methodology has been used to forecast the half-hourly electricity demand for power systems in the Indonesia National Electricity Market in West Java region. Experiments were conducted by testing various of learning rate and learning data input. Performance of this methodology will be validated with real data from the national of electricity company. The result of observations show that the proposed formula is very effective to short-term load forecasting in the case of anomalous load. Hybrid ANN-Swarm Particle relatively simple and easy as a analysis tool by engineers.

  12. Thermal energy storage for electricity-driven space heating in a day-ahead electricity market

    DEFF Research Database (Denmark)

    Pensini, Alessandro

    2012-01-01

    of electricity in a system with a TES unit to the case where no storage is in use and the entire heat requirement is fulfilled by purchasing electricity according to the actual load. The study had two goals: 1. Determining how the size – in terms of electricity input (Pmax) and energy capacity (Emax...

  13. Load Situation Awareness Design for Integration in Multi-Energy System

    DEFF Research Database (Denmark)

    Cai, Hanmin; You, Shi; Bindner, Henrik W.

    2017-01-01

    -energy system, thermal load management will benefit not only electric network but also district heating network. Electric heater will be the main focus of this paper as a common thermal load. A situation awareness framework for its integration into electric and district heating network will be proposed...

  14. Hybrid electric vehicle power management system

    Energy Technology Data Exchange (ETDEWEB)

    Bissontz, Jay E.

    2015-08-25

    Level voltage levels/states of charge are maintained among a plurality of high voltage DC electrical storage devices/traction battery packs that are arrayed in series to support operation of a hybrid electric vehicle drive train. Each high voltage DC electrical storage device supports a high voltage power bus, to which at least one controllable load is connected, and at least a first lower voltage level electrical distribution system. The rate of power transfer from the high voltage DC electrical storage devices to the at least first lower voltage electrical distribution system is controlled by DC-DC converters.

  15. Electric Power

    Institute of Scientific and Technical Information of China (English)

    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.

  16. Electricity economics

    CERN Document Server

    Hu, Zhaoguang

    2013-01-01

    Systematically analyzing for the first time the production output from electricity consumption for enterprises, sectors, and industries, this study uses the function of EAI (electricity as input), and includes national E-GDP figures for more than 20 countries.

  17. Electrical actuators applications and performance

    CERN Document Server

    De Fornel, Bernard

    2013-01-01

    This helpful resource covers a large range of information regarding electrical actuators. In particular, robustness, a very problematic issue, is fully explored in a dedicated chapter. The text also deals with he estimate of non-measurable mechanical variables by examining the estimate of load moment, then observation of the positioning of a command without mechanical sensor. Finally, it examines the conditions needed to measure variables and real implementation of numerical algorithms. This is a key working resource for electrical engineers.

  18. Electrical contracting

    CERN Document Server

    Neidle, Michael

    2013-01-01

    Electrical Contracting, Second Edition is a nine-chapter text guide for the greater efficiency in planning and completing installations for the design, installation and control of electrical contracts. This book starts with a general overview of the efficient cabling and techniques that must be employed for safe wiring design, as well as the cost estimation of the complete electrical contract. The subsequent chapters are devoted to other electrical contracting requirements, including electronic motor control, lighting, and electricity tariffs. A chapter focuses on the IEE Wiring Regulations an

  19. Distribution load estimation (DLE)

    Energy Technology Data Exchange (ETDEWEB)

    Seppaelae, A.; Lehtonen, M. [VTT Energy, Espoo (Finland)

    1998-08-01

    The load research has produced customer class load models to convert the customers` annual energy consumption to hourly load values. The reliability of load models applied from a nation-wide sample is limited in any specific network because many local circumstances are different from utility to utility and time to time. Therefore there is a need to find improvements to the load models or, in general, improvements to the load estimates. In Distribution Load Estimation (DLE) the measurements from the network are utilized to improve the customer class load models. The results of DLE will be new load models that better correspond to the loading of the distribution network but are still close to the original load models obtained by load research. The principal data flow of DLE is presented

  20. Electric vehicles

    Science.gov (United States)

    1990-03-01

    Quiet, clean, and efficient, electric vehicles (EVs) may someday become a practical mode of transportation for the general public. Electric vehicles can provide many advantages for the nation's environment and energy supply because they run on electricity, which can be produced from many sources of energy such as coal, natural gas, uranium, and hydropower. These vehicles offer fuel versatility to the transportation sector, which depends almost solely on oil for its energy needs. Electric vehicles are any mode of transportation operated by a motor that receives electricity from a battery or fuel cell. EVs come in all shapes and sizes and may be used for different tasks. Some EVs are small and simple, such as golf carts and electric wheel chairs. Others are larger and more complex, such as automobile and vans. Some EVs, such as fork lifts, are used in industries. In this fact sheet, we will discuss mostly automobiles and vans. There are also variations on electric vehicles, such as hybrid vehicles and solar-powered vehicles. Hybrid vehicles use electricity as their primary source of energy, however, they also use a backup source of energy, such as gasoline, methanol or ethanol. Solar-powered vehicles are electric vehicles that use photovoltaic cells (cells that convert solar energy to electricity) rather than utility-supplied electricity to recharge the batteries. These concepts are discussed.

  1. HYBRID AND INTEGRATED APPROACH TO SHORT TERM LOAD FORECASTING

    Directory of Open Access Journals (Sweden)

    J. P. Rothe,

    2010-12-01

    Full Text Available The forecasting of electricity demand has become one of the major research fields in Electrical Engineering. In recent years, much research has been carried out on the application of artificial intelligence techniques to the Load-Forecasting problem. Various Artificial Intelligence (AI techniques used for load forecasting are Expert systems, Fuzzy, Genetic Algorithm, Artificial Neural Network (ANN. This research work is an attempt to apply hybrid and ntegrated effort to forecast load. Regression, Fuzzy and Neural alongwith Genetic Algorithm will empower the analysts to strongly forecast fairly accurate load demand on hourly base.

  2. Short-Term Load Forecasting for Microgrids Based on Artificial Neural Networks

    Directory of Open Access Journals (Sweden)

    Antonio J. Sanchez-Esguevillas

    2013-03-01

    Full Text Available Electricity is indispensable and of strategic importance to national economies. Consequently, electric utilities make an effort to balance power generation and demand in order to offer a good service at a competitive price. For this purpose, these utilities need electric load forecasts to be as accurate as possible. However, electric load depends on many factors (day of the week, month of the year, etc., which makes load forecasting quite a complex process requiring something other than statistical methods. This study presents an electric load forecast architectural model based on an Artificial Neural Network (ANN that performs Short-Term Load Forecasting (STLF. In this study, we present the excellent results obtained, and highlight the simplicity of the proposed model. Load forecasting was performed in a geographic location of the size of a potential microgrid, as microgrids appear to be the future of electric power supply.

  3. Energy modelling of PREMIO platform, an architecture dedicated to dynamic load management on electric grid; Modelisation energetique de la plate-forme PREMIO, une architecture dediee a la gestion dynamique de la charge sur le reseau electrique

    Energy Technology Data Exchange (ETDEWEB)

    Bougnol, P.; Imbert, P. [ParisTech et l' Institut EIFER, 75 (France); Chartres, S. [Institut EIFER (France); Normand, O. [EDF R and D/EIFER (France)

    2010-01-15

    The cluster of competencies CapEnergies in co-founding with the PACA region launched PREMIO project in 2008. This project aims at implementing a local, innovative and replicable energy architecture that optimizes dynamic load management in order to diminish constraints on power grid and CO{sub 2} emissions. Technical, economical, environmental and sociological impacts of this technology are a strategic issue for project partners that elaborate the business models and future energy policies.The model developed in the frame of PREMIO project provides at local scale (district to city) a method to assess the impact of PREMIO architecture on load curve, CO{sub 2} emissions and energy savings. A case study realised in Lambesc (PACA region) simulates two deployment scenarios of manageable systems: 100% and 50% of the territory consumption, storage and production usages. The exploitation of these results gives prospects to improve this model. (authors)

  4. Wind Loads on Structures

    DEFF Research Database (Denmark)

    Dyrbye, Claes; Hansen, Svend Ole

    pressure to structural response) and design criteria. Starting with an introduction of the wind load chain, the book moves on to meteorological considerations, atmospheric boundary layer, static wind load, dynamic wind load and scaling laws used in wind-tunnel tests. The dynamic wind load covers vibrations......Wind loads have to be taken into account when designing civil engineering structures. The wind load on structures can be systematised by means of the wind load chain: wind climate (global), terrain (wind at low height), aerodynamic response (wind load to pressure), mechanical response (wind...

  5. Distribution load estimation - DLE

    Energy Technology Data Exchange (ETDEWEB)

    Seppaelae, A. [VTT Energy, Espoo (Finland)

    1996-12-31

    The load research project has produced statistical information in the form of load models to convert the figures of annual energy consumption to hourly load values. The reliability of load models is limited to a certain network because many local circumstances are different from utility to utility and time to time. Therefore there is a need to make improvements in the load models. Distribution load estimation (DLE) is the method developed here to improve load estimates from the load models. The method is also quite cheap to apply as it utilises information that is already available in SCADA systems

  6. Wind Loads on Structures

    DEFF Research Database (Denmark)

    Dyrbye, Claes; Hansen, Svend Ole

    pressure to structural response) and design criteria. Starting with an introduction of the wind load chain, the book moves on to meteorological considerations, atmospheric boundary layer, static wind load, dynamic wind load and scaling laws used in wind-tunnel tests. The dynamic wind load covers vibrations......Wind loads have to be taken into account when designing civil engineering structures. The wind load on structures can be systematised by means of the wind load chain: wind climate (global), terrain (wind at low height), aerodynamic response (wind load to pressure), mechanical response (wind...

  7. 舵机加载系统的自适应滑模控制策略研究%Research for adaptive sliding mode control in aircraft rudder electric loading system

    Institute of Scientific and Technical Information of China (English)

    史本杰; 王易炜

    2012-01-01

    舵机加载系统主要用于模拟导弹在飞行过程中舵面受到的各种气动力矩,但存在力矩效率低,多余力较多,干扰复杂等特点.为使电动加载系统的仿真度和力矩精度进一步提高,采用自适应滑模控制对多余力矩和其他位置干扰进行抑制,同时对滑模控制的切换函数进行改进,以削弱系统存在的抖振.仿真结果显示,加载系统的精度和抗干扰能力有进一步提高.%The steering mechanism loading system is used to simulate various aerodynamic torques that the missile rudder suffers from flying, but it has some characteristics, such as low efficiency, much redundant torque and complex disturbance. In order to improve the precision and reliability of the steering mechanism loading system, adaptive sliding mode control was used and the switch function of sliding mode control (SMC) was modified to weaken system chattering. The simulation result indicates that the precision and anti-jamming of the loading system are improved.

  8. 'Development and introduction of ice water conveyance system and verification of low temperature blast system' for leveling off electric power load; Denryoku fuka heijunka wo misueta 'hyosui hanso hoshiki no kaihatsu donyu to teion sofu hoshiki no kensho'

    Energy Technology Data Exchange (ETDEWEB)

    Kuriyama, T. [Nikken Sekkei Ltd., Osaka (Japan)

    1999-11-05

    From the view point of the earth environment protection, energy-saving in the field of building air-conditioning has become increasingly important. On the other hand, the utilization of nighttime electric power is needed to ease the electric power supply and demand problem, and in this connection, a wider introduction of the ice heat storage system is recommended as one of the means to cope with such a problem. However, the ice heat storage system also has problems to be solved such as energy savability, and economy. Under such circumstances, various technical research and development efforts as well as evaluation thereof have been made centering around the 'technical development of the ice water conveyance system' and the 'evaluation of the low temperature blast system' for energy-saving, facility cost reduction and electric power load leveling off, and as a matter of fact these systems have been installed in actual buildings with useful results. (author)

  9. Variable speed electrical actuators. 3, converter-network and converter-motor-load interactions; Entrainements electriques a vitesse variable. 3, interactions convertisseur-reseau et convertisseur-moteur-charge

    Energy Technology Data Exchange (ETDEWEB)

    Bonal, J.; Seguier, G.

    2000-07-01

    This third part of the study of variable speed electrical actuators analyzes the harmonics generated by the converter, which are the main cause of disturbances related to such actuators. It analyzes also the propagation and effects of these harmonics when injected in the power network, and the effects of the use of a static converter for the power supply of the motor. (J.S.)

  10. Ancillary-service details: regulation, load following, and generator response

    Energy Technology Data Exchange (ETDEWEB)

    Hirst, E.; Kirby, B.

    1996-09-01

    The purpose of this report is to examine empirically these intrahour and interhour load changes and the responses of a utility`s generating resources to those load changes. We analyze data, primarily from one control area, to see how it maintains ACE close to zero in an effort to meet the A1 and A2 criteria. Overall, we estimate that load following costs US electric utilities over one billion dollars a year. We first test alternative ways to identify trends over multihour periods using both regression analysis and rolling averages. Then, we consider several metrics for intrahour load following. Next we examine characteristics of load following for different time-averaging periods and compare the dynamics of loads and load following generation across these time periods. Finally, we consider the contribution of each load to the total load following requirements of the control area.

  11. Power load leveling and energy saving measures for office buildings. Power load leveling and energy saving technology for the new building of the Kobe branch of the Kansai Electric Power Co., and its effect; Office biru no denryoku fuka heijunka sho energy hosaku. Kobe shiten shinshaoku ni okeru denryoku fuka heijunka sho energy gijutsu to sono koka

    Energy Technology Data Exchange (ETDEWEB)

    Tsuchiyama, M. [Kansai Electric Power Co. Inc., Osaka (Japan)

    1999-06-10

    This paper presents power load leveling and energy saving measures for heat source, air conditioning and lighting of the new Kobe branch building. The low-temperature hot-air system adopts an ice storage system, and reduces blowing power by 12 degreesC blowing in place of normal 16 degreesC blowing, and an initial cost by duct size reduction. The continuous air conditioning system levels an initial peak load of air conditioning as compared with normal air conditioning only for working hours for buildings with large heat capacity. In addition, as power load leveling measures for the whole building, the complete heat storage system using an underground internal melting type ice storage tank is adopted. Energy saving for lighting is achieved with a dimming lighting controlling its lighting output by inverter. The following effects are expected by these new technologies: Load leveling effect of 30%, energy saving effect of 20.2% and CO{sub 2} reduction effect of 24.1%. (NEDO)

  12. Systems and methods for providing power to a load based upon a control strategy

    Energy Technology Data Exchange (ETDEWEB)

    Perisic, Milun; Lawrence, Christopher P; Ransom, Ray M; Kajouke, Lateef A

    2014-11-04

    Systems and methods are provided for an electrical system. The electrical system, for example, includes a first load, an interface configured to receive a voltage from a voltage source, and a controller configured to receive the voltage through the interface and to provide a voltage and current to the first load. The controller may be further configured to, receive information on a second load electrically connected to the voltage source, determine an amount of reactive current to return to the voltage source such that a current drawn by the electrical system and the second load from the voltage source is substantially real, and provide the determined reactive current to the voltage source.

  13. Atmospheric electricity

    CERN Document Server

    Chalmers, J Alan

    1957-01-01

    Atmospheric Electricity brings together numerous studies on various aspects of atmospheric electricity. This book is composed of 13 chapters that cover the main problems in the field, including the maintenance of the negative charge on the earth and the origin of the charges in thunderstorms. After a brief overview of the historical developments of atmospheric electricity, this book goes on dealing with the general principles, results, methods, and the MKS system of the field. The succeeding chapters are devoted to some aspects of electricity in the atmosphere, such as the occurrence and d

  14. Electrical stator

    Science.gov (United States)

    Fanning, Alan W.; Olich, Eugene E.

    1994-01-01

    An electrical stator of an electromagnetic pump includes first and second spaced apart coils each having input and output terminals for carrying electrical current. An elongate electrical connector extends between the first and second coils and has first and second opposite ends. The connector ends include respective slots receiving therein respective ones of the coil terminals to define respective first and second joints. Each of the joints includes a braze filler fixedly joining the connector ends to the respective coil terminals for carrying electrical current therethrough.

  15. 1995 Pacific Northwest Loads and Resources Study.

    Energy Technology Data Exchange (ETDEWEB)

    United States. Bonneville Power Administration.

    1995-12-01

    The study establishes the planning basis for supplying electricity to customers. The study presents projections of regional and Federal system load and resource capabilities, and serves as a benchmark for annual BPA determinations made pursuant to the 1981 regional power sales contracts.

  16. 采用负荷电量计算低压配电台区理论线损的牛拉法%Newton-Raphson method for theoretical line loss calculation of low-voltage distribution transformer district by using the load electrical energy

    Institute of Scientific and Technical Information of China (English)

    刘庭磊; 王韶; 张知; 朱姜峰

    2015-01-01

    In order to calculate the theoretical line loss of low-voltage distribution transformer district and improve the line loss management level by using automatic meter reading system, a Newton-Raphson method to calculate the theoretical line loss of low-voltage distribution transformer district by adopting the load electrical energy is proposed. On the basis of the equivalent resistance method and the electrical energy acquired from the watt-hour meters of customers, the mathematical model of regarding theoretical line loss of transformer district as a variable is created. The model introduces relationship between load shape coefficients and the average load current, and the line loss modified coefficient of unbalanced three-phase load. The procedure of the Newton-Raphson method to solve the model is presented. Case analyses show that the proposed method can not only calculate the theoretical line loss of low-voltage distribution transformer district, but also provide the information to identify unknown line loss.%为计算低压配电台区理论线损和利用远程自动抄表系统提高管理线损水平,提出一种采用负荷电量计算低压配电台区理论线损的牛拉法.该方法基于等值电阻法和用户电能表实抄电量,通过引入线路负荷曲线形状系数与平均负荷电流的关系和三相负荷不平衡线损修正系数建立以台区理论线损为变量的数学模型.给出了运用牛拉法求解该模型的实现过程.算例分析表明,提出的方法不仅能够计算低压配电台区的理论线损,而且能够为识别不明线损提供信息.

  17. Transmission grid requirements with scattered and flutuating renewable electricity sources

    DEFF Research Database (Denmark)

    Østergaard, Poul Alberg

    2002-01-01

    Denmark is in a situation with many scattered sources of electricity, that are not controlled by the central load dispatch. At the same time, Denmark is being used as an electricity transit corridor between Norway/Sweden and Germany. Through energy systems analyses and load-flow analyses, it is d...

  18. Fuel Cell Equivalent Electric Circuit Parameter Mapping

    DEFF Research Database (Denmark)

    Jeppesen, Christian; Zhou, Fan; Andreasen, Søren Juhl

    In this work a simple model for a fuel cell is investigated for diagnostic purpose. The fuel cell is characterized, with respect to the electrical impedance of the fuel cell at non-faulty conditions and under variations in load current. Based on this the equivalent electrical circuit parameters c...

  19. 基于需求响应的电动汽车集群充电负荷建模及容量边界控制策略%Study on Modeling of Aggregated Charging Load of Electric Vehicles and Control Strategy by Adjusting Capacity Boundaries Based on Demand Response

    Institute of Scientific and Technical Information of China (English)

    孙强; 许方园; 唐佳; 王丹; 罗凤章

    2016-01-01

    对电动汽车充电进行合理有序的控制是实现大规模电动汽车入网的关键。首先介绍了一种电动汽车集群的分层分区域的电动汽车控制架构。其次,建立了电动汽车集群的控制模型,并在此基础之上提出了一种通过改变电动汽车可调容量边界的电动汽车集群的需求响应控制策略。最后,通过算例分析,首先研究了模型中的参数对电动汽车集群充电负荷的影响,其次验证了文中提出的控制模型和策略,仿真结果表明,在满足用户用电需求的基础上,文中建立的电动汽车控制模型和控制策略能够很好地实现电动汽车集群需求响应的功能。%Reasonable and orderly control of electric vehicle charging is the key to realizelarge-scale electric vehiclesaccessing to power grid.Firstly,a layered and partitioned control framework of electric vehicle clusteris presented. Secondly, charging model of aggregated electric vehicles is established.Onthisbasis,a control strategyof aggregated electric vehicles for demand response is proposed.It adjustsEVs charging capacity boundaryto realize desired control. Finally, influence of model parameters is studied, and the control model and strategy are verified.Simulation results show that the control model and strategy can achieve objectiveof electric vehicle charging load without missing customerneed.

  20. Radio Frequency Power Load and Associated Method

    Science.gov (United States)

    Srinivasan, V. Karthik (Inventor); Freestone, Todd M. (Inventor); Sims, William Herbert, III (Inventor)

    2014-01-01

    A radio frequency power load and associated method. A radio frequency power load apparatus may include a container with an ionized fluid therein. The apparatus may include one conductor immersed in a fluid and another conductor electrically connected to the container. A radio frequency transmission system may include a radio frequency transmitter, a radio frequency amplifier connected to the transmitter and a radio frequency power load apparatus connected to the amplifier. The apparatus may include a fluid having an ion source therein, one conductor immersed in a fluid, and another conductor electrically connected to the container. A method of dissipating power generated by a radio frequency transmission system may include constructing a waveguide with ionized fluid in a container and connecting the waveguide to an amplifier of the transmission system.

  1. Electric machine

    Science.gov (United States)

    El-Refaie, Ayman Mohamed Fawzi [Niskayuna, NY; Reddy, Patel Bhageerath [Madison, WI

    2012-07-17

    An interior permanent magnet electric machine is disclosed. The interior permanent magnet electric machine comprises a rotor comprising a plurality of radially placed magnets each having a proximal end and a distal end, wherein each magnet comprises a plurality of magnetic segments and at least one magnetic segment towards the distal end comprises a high resistivity magnetic material.

  2. Load controller and method to enhance effective capacity of a photovotaic power supply using a dynamically determined expected peak loading

    Science.gov (United States)

    Perez, Richard

    2003-04-01

    A load controller and method are provided for maximizing effective capacity of a non-controllable, renewable power supply coupled to a variable electrical load also coupled to a conventional power grid. Effective capacity is enhanced by monitoring power output of the renewable supply and loading, and comparing the loading against the power output and a load adjustment threshold determined from an expected peak loading. A value for a load adjustment parameter is calculated by subtracting the renewable supply output and the load adjustment parameter from the current load. This value is then employed to control the variable load in an amount proportional to the value of the load control parameter when the parameter is within a predefined range. By so controlling the load, the effective capacity of the non-controllable, renewable power supply is increased without any attempt at operational feedback control of the renewable supply. The expected peak loading of the variable load can be dynamically determined within a defined time interval with reference to variations in the variable load.

  3. 基于TMS320F28335的恒流型馈能式电子负载的设计%Design of a kind of constant-current energy-feedback electric load based on TMS320F28335

    Institute of Scientific and Technical Information of China (English)

    张胜高; 张庆范; 王思尧; 侯典立

    2012-01-01

    In order to solve the energy-wasting problem of power devices in the process of burn-in test, a kind of constant- current energy-feedback electric load based on TMS320F28335DSP is designed. It describes the operating feathers of a phase shifting full bridge ZVS PWM converter with clamping diodes in the primary side of transformer; and a feasible phase shifting PWM wave digital control method is adopted. Based on the method of voltage feed-forward in DC/DC, and current-voltage dual loop control in DC/AC, a 3.5 kW electric load is made. The test results show that this device has stable performance, fast corresponding speed, and can meet the requirements of burn-in test and grid feedback.%针对电源设备出厂老化测试电能浪费问题,设计了一种基于TMS320F28335DSP的恒流型馈能式电子负载。描述了一种原边带箝位二极管的ZVS移相全桥变换器的工作特点,采用了一种简便易行的移相波形数字控制方法 ;基于DC/DC电压前馈、DC/AC电压电流双环控制方法,研制出一台3.5 kW试验样机。实验结果表明:该系统性能稳定、调节速度快,能很好地满足测试老化及馈网要求。

  4. Recharging infrastructure for electric vehicles; Las infraestructuras de recarga para el vehiculo electrico

    Energy Technology Data Exchange (ETDEWEB)

    Asin Munoa, J.

    2012-11-01

    Load managers are those stakeholders being themselves electric electricity consumers, are able to resell to their customers electricity; intended to charge electric vehicles. Figure cargo manager is critical in the successful development of charging infrastructure for electric vehicles, and occupies a conceptually similar role to that of mobile operator. (Author)

  5. 1997 Pacific Northwest Loads and Resources Study.

    Energy Technology Data Exchange (ETDEWEB)

    United States. Bonneville Power Administration.

    1997-12-01

    The 1997 White Book is presented in two documents: (1) this summary of Federal system and Pacific Northwest region loads and resources; and (2) a technical appendix detailing the loads and resources for each major Pacific Northwest generating utility. Data detailing Pacific Northwest non-utility generating (NUG) resources is also available upon request. This analysis updates the 1996 pacific Northwest Loads and Resources Study, published in December 1996. In this loads and resources study, resource availability is compared with a medium forecast of electricity consumption. This document analyzes the Pacific Northwest`s projected loads and available generating resources in two parts: (1) the loads and resources of the Federal system, for which BPA is the marketing agency; and (2) the larger Pacific Northwest regional power system which includes loads and resources in addition to the Federal system. This study presents the Federal system and regional analyses for the medium load forecast. This analysis projects the yearly average energy consumption and resource availability for Operating Years (OY) 1998--99 through 2007--08.

  6. Optimization of electric energy

    Energy Technology Data Exchange (ETDEWEB)

    Kraner, A.R.

    1984-02-01

    Several examples are used to show how electrical energy consumption can be reduced using appropriate consultation. According to on detailed analysis on energy consumption, a reduction can be achieved with peak loads as well as with the application of a combined emergency power supply - thermal machine, at least for middle- and large-sized buildings. The calculations for profitability are extended for the following areas: energy-saving light systems, ventilation plants, elevator plants, and kitchen equipment. A comment on employee motivation closes the report.

  7. Electrical machines with Matlab

    CERN Document Server

    Gonen, Turan

    2011-01-01

    Basic ConceptsDistribution SystemImpact of Dispersed Storage and GenerationBrief Overview of Basic Electrical MachinesReal and Reactive Powers in Single-Phase AC CircuitsThree-Phase CircuitsThree-Phase SystemsUnbalanced Three-Phase LoadsMeasurement of Average Power in Three-Phase CircuitsPower Factor CorrectionMagnetic CircuitsMagnetic Field of Current-Carrying ConductorsAmpère's Magnetic Circuital LawMagnetic CircuitsMagnetic Circuit with Air GapBrief Review of FerromagnetismMagnetic Core LossesHow to Determine Flux for a Given MMFPermanent MagnetsTransformersTransformer ConstructionBrief Rev

  8. Testing of Uninterruptible Power Supplies with nonlinear loads

    Science.gov (United States)

    Heydt, Gerald; Briggs, Steve; Holcomb, Franklin; Edgar, Daiva

    1994-09-01

    Uninterruptible power supplies (UPS's) are used to provide power to sensitive and critical loads when the commercial supply has been interrupted. These loads may be nonlinear, which in the military often includes communications equipment, adjustable speed drives, fluorescent lighting, and mainframe and small computers. Most electrical characteristics of UPS's are not currently subject to codes and standards, and there are no military specifications for UPS's. Existing standards assume that UPS's will be operated with linear loads. Since most UPS systems are operated with nonlinear loads, there is concern that UPSs will suffer degraded performance or failure when operated with these loads. This work developed a test methodology by which UPS systems can be tested and their susceptibility to nonlinear loads quantified. The tests measure load transfer, efficiency, heating, load support, voltage regulation, and isolation. Several commercially available UPS systems are recommended for testing.

  9. Electric fields and electrical insulation

    DEFF Research Database (Denmark)

    McAllister, Iain Wilson

    2002-01-01

    The adoption of a field-theoretical approach to problems arising in the framework of electrical insulation is discussed with reference to six main topics, which have been addressed over the last 30 years. These include uniform field electrodes, Green's differential equation, electrode surface......, it is amply demonstrated that such an approach can lead to significant progress in many areas of electrical insulation....

  10. Probabilistic load forecasting via Quantile Regression Averaging on sister forecasts

    OpenAIRE

    Bidong Liu; Jakub Nowotarski; Tao Hong; Rafal Weron

    2015-01-01

    Majority of the load forecasting literature has been on point forecasting, which provides the expected value for each step throughout the forecast horizon. In the smart grid era, the electricity demand is more active and less predictable than ever before. As a result, probabilistic load forecasting, which provides additional information on the variability and uncertainty of future load values, is becoming of great importance to power systems planning and operations. This paper proposes a prac...

  11. Optimal load scheduling in commercial and residential microgrids

    Science.gov (United States)

    Ganji Tanha, Mohammad Mahdi

    Residential and commercial electricity customers use more than two third of the total energy consumed in the United States, representing a significant resource of demand response. Price-based demand response, which is in response to changes in electricity prices, represents the adjustments in load through optimal load scheduling (OLS). In this study, an efficient model for OLS is developed for residential and commercial microgrids which include aggregated loads in single-units and communal loads. Single unit loads which include fixed, adjustable and shiftable loads are controllable by the unit occupants. Communal loads which include pool pumps, elevators and central heating/cooling systems are shared among the units. In order to optimally schedule residential and commercial loads, a community-based optimal load scheduling (CBOLS) is proposed in this thesis. The CBOLS schedule considers hourly market prices, occupants' comfort level, and microgrid operation constraints. The CBOLS' objective in residential and commercial microgrids is the constrained minimization of the total cost of supplying the aggregator load, defined as the microgrid load minus the microgrid generation. This problem is represented by a large-scale mixed-integer optimization for supplying single-unit and communal loads. The Lagrangian relaxation methodology is used to relax the linking communal load constraint and decompose the independent single-unit functions into subproblems which can be solved in parallel. The optimal solution is acceptable if the aggregator load limit and the duality gap are within the bounds. If any of the proposed criteria is not satisfied, the Lagrangian multiplier will be updated and a new optimal load schedule will be regenerated until both constraints are satisfied. The proposed method is applied to several case studies and the results are presented for the Galvin Center load on the 16th floor of the IIT Tower in Chicago.

  12. Electrical Conductivity.

    Science.gov (United States)

    Hershey, David R.; Sand, Susan

    1993-01-01

    Explains how electrical conductivity (EC) can be used to measure ion concentration in solutions. Describes instrumentation for the measurement, temperature dependence and EC, and the EC of common substances. (PR)

  13. Electrical Injuries

    Science.gov (United States)

    ... it can pass through your body and cause injuries. These electrical injuries can be external or internal. You may have one or both types. External injuries are skin burns. Internal injuries include damage to ...

  14. Electricity derivatives

    CERN Document Server

    Aïd, René

    2015-01-01

    Offering a concise but complete survey of the common features of the microstructure of electricity markets, this book describes the state of the art in the different proposed electricity price models for pricing derivatives and in the numerical methods used to price and hedge the most prominent derivatives in electricity markets, namely power plants and swings. The mathematical content of the book has intentionally been made light in order to concentrate on the main subject matter, avoiding fastidious computations. Wherever possible, the models are illustrated by diagrams. The book should allow prospective researchers in the field of electricity derivatives to focus on the actual difficulties associated with the subject. It should also offer a brief but exhaustive overview of the latest techniques used by financial engineers in energy utilities and energy trading desks.

  15. Lightening the Load

    OpenAIRE

    Remington, Anna M.; Swettenham, John G.; Lavie, Nilli

    2012-01-01

    Autism spectrum disorder (ASD) research portrays a mixed picture of attentional abilities with demonstrations of enhancements (e.g., superior visual search) and deficits (e.g., higher distractibility). Here we test a potential resolution derived from the Load Theory of Attention (e.g., Lavie, 2005). In Load Theory, distractor processing depends on the perceptual load of the task and as such can only be eliminated under high load that engages full capacity. We hypothesize that ASD involves enh...

  16. Increase of energy efficiency of testing of traction electric machines of direct and pulsating current

    Directory of Open Access Journals (Sweden)

    A.M. Afanasov

    2015-03-01

    Full Text Available The results of the analysis of the effect of the load current of traction electric machines when tested for heating on the total electricity consumption for the test are presented. It is shown that increase of load current at the heating test permits to significantly reduce the consumption of electrical energy, and reduce the testing time without reducing its quality.

  17. BP Network Based on Particle Swarm Optimization of Short- term Electric Load Forecasting%基于粒子群优化RP网络短期电力负荷预测方法

    Institute of Scientific and Technical Information of China (English)

    姚刚; 陈政石; 李晓竹

    2011-01-01

    As conventional BP network for the slow convergence and easy to fall into local minimum problem, the use of LM algorithm for network training, the improved particle swarm optimization BP network initial weights and threshold. Application of this method in the text grid in a city short - term load forecasting, showed that compared with conventional BP network, L- M algorithm to improve prediction models. This article describes the results of the prediction algorithm in the prediction accuracy and speed have increased greatly.%针对常规BP网络收敛速度慢,易陷入局部极小值等问题,采用L—M算法对网络进行训练,利用改进粒子群算法优化BP网络初始权值和阈值。将该方法应用在南方某市短期电网负荷预测中,预测结果表明,相较于常规BP网络、L—M算法改进预测模型,该预测算法在预测结果精度和速度上均有较大幅度提高。

  18. A strategy for short-term load forecasting in Ireland

    OpenAIRE

    Fay, Damien

    2004-01-01

    Electric utilities require short-term forecasts of electricity demand (load) in order to schedule generating plant up to several days ahead on an hourly basis. Errors in the forecasts may lead to generation plant operation that is not required or sub-optimal scheduling of generation plants. In addition, with the introduction of the Electricity Regulation Act 1999, a deregulated market structure has been introduced, adding increased impetus to reducing forecast error and the associated costs. ...

  19. Electrical Emissions from Concrete under Three-point Bending Tests

    Institute of Scientific and Technical Information of China (English)

    LIU Qingping; SUN Mingqing; LI Zhuoqiu; LI Guoqiang

    2005-01-01

    Electrical emission(EM) signals, which are generated from the concrete specimens under three-point bending tests, were conducted. It is shown that electrical emission phenomena are related to cracking of the specimens, cohesive failure, contact-separation etc. The simultaneous appearance of electric emission signals and visible cracks during the flexure loading of beams was also observed.

  20. 46 CFR 28.850 - Main source of electrical power.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Main source of electrical power. 28.850 Section 28.850... FISHING INDUSTRY VESSELS Aleutian Trade Act Vessels § 28.850 Main source of electrical power. (a) Applicability: Each vessel that relies on electricity to power any of the following essential loads must have at...

  1. 46 CFR 28.355 - Main source of electrical power.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Main source of electrical power. 28.355 Section 28.355... Operate With More Than 16 Individuals on Board § 28.355 Main source of electrical power. (a) Applicability. Each vessel that relies on electricity to power any of the following essential loads must have at least...

  2. Loads Providing Ancillary Services: Review of International Experience

    Energy Technology Data Exchange (ETDEWEB)

    Heffner, Grayson; Goldman, Charles; Kintner-Meyer, Michael

    2007-05-01

    In this study, we examine the arrangements for and experiences of end-use loads providing ancillary services (AS) in five electricity markets: Australia, the United Kingdom (UK), the Nordic market, and the ERCOT and PJM markets in the United States. Our objective in undertaking this review of international experience was to identify specific approaches or market designs that have enabled customer loads to effectively deliver various ancillary services (AS) products. We hope that this report will contribute to the ongoing discussion in the U.S. and elsewhere regarding what institutional and technical developments are needed to ensure that customer loads can meaningfully participate in all wholesale electricity markets.

  3. Taking a Load Off.

    Science.gov (United States)

    Kenny, John

    1995-01-01

    Discusses the snow -load capacity of school roofs and how understanding this data aids in planning preventive measures and easing fear of roof collapse. Describes how to determine snow-load capacity, and explains the load-bearing behavior of flat versus sloped roofs. Collapse prevention measures are highlighted. (GR)

  4. 提高电动加载系统输出平滑的CMAC复合控制%Improving the output smoothing of the electric loading system based on the CMAC+PD compound control strategy

    Institute of Scientific and Technical Information of China (English)

    杨波; 程龙

    2013-01-01

    Cerebellar model articulation controller and proportional derivative (CMAC +PD) compound control strategy had an unsmooth output,which would increase the vibration of loading motor and decrease the control performance.An improved CMAC+PD compound control strategy with a new weights updating formula was proposed after analyzing the reason of the unsmooth problem.The improved CMAC+PD compound control strategy could not only decrease the error,but also improve the output smoothness in the weights updating process.The simulation and experimental results demonstrated that the improved CMAC+PD compound control strategy has a more smooth output and a better stability performance than the conventional CMAC+PD compound control strategy.And the steady state error is reduced by 21%.%CMAC(Cerebellar Model Articulation Controller)和PD(Proportional Derivative)复合控制算法有时因输出不平滑会引起加载电机抖动而影响控制效果.通过对该输出不平滑问题进行分析,提出了一种新的提高输出平滑性的改进CMAC复合控制算法,该方法通过新的权值更新公式,在权值更新时直接达到减小误差和提高输出平滑性的目的.仿真和实验结果表明:改进后的算法能够有效提高输出平滑性,降低了21%的稳态误差,且保证在加载时有良好的稳定性和抗干扰能力.

  5. An Electricity Market Model With Distributed Generation and Interruptible Load Under Incomplete Information%计及分布式发电和不完全信息可中断负荷选择的电力市场模型

    Institute of Scientific and Technical Information of China (English)

    杨彦; 陈皓勇; 张尧; 李方兴; 荆朝霞; 王玉荣

    2011-01-01

    Distributed generation (DG) and interruptible load are two important resources of smart grid. Because different kinds of power users have different willingness to curtail their demands, the type of the interruptible loads owned by a distribution company (DISCO) was assumed to be a stochastic variable which meets a discrete distribution. Further an energy acquisition model with the distributed generation and the interruptible load under incomplete information was formulated for the distribution company. Comprehensively taking into consideration of the strategic behavior of a generation company (GENCO), the integrated electricity market model under incomplete information was proposed finally. The coevolutionary approach was improved and further employed to solve the Bayesian Nash equilibrium of the market model. The IEEE 9-bus system appropriately modified was used to illustrate the proposed model and approach. The simulation results show that the market equilibrium is greatly affected by the distributed generation and interruptible load, the strategic behavior of the generation company and the incomplete information.%分布式发电(distributed generation,DG)与可中断负荷是智能电网的2种重要资源。针对电力用户停电意愿不尽相同,将配电公司的可中断负荷类型建模为离散分布的随机变量,进而建立具有分布式发电与不完全信息可中断负荷选择的配电公司能量获取模型,综合考虑到发电公司的竞价策略行为,最后建立了完整的不完全信息博弈下的电力市场模型。针对不完全信息博弈的特征,扩展改进了协同进化算法,并用于求解市场贝叶斯纳什均衡。修正的IEEE9节点系统验证了模型与求解方法的有效性。结果表明分布式发电与可中断负荷、发电公司策略行为及不完全信息对市场均衡有着重要的影响。

  6. Compensator configurations for load currents' symmetrization

    Science.gov (United States)

    Rusinaru, D.; Manescu, L. G.; Dinu, R. C.

    2016-02-01

    This paper approaches aspects regarding the mitigation effects of asymmetries in 3-phase 3-wire networks. The measure consisting in connecting of load current symmetrization devices at the load coupling point is presented. A time-variation of compensators parameters is determined as a function of the time-recorded electrical values. The general sizing principle of the load current symmetrization reactive components is based on a simple equivalent model of the unbalanced 3-phase loads. By using these compensators a certain control of the power components transits is ensured in the network. The control is based on the variations laws of the compensators parameters as functions of the recorded electrical values: [B] = [T]·[M]. The link between compensator parameters and measured values is ensured by a transformation matrix [T] for each operation conditions of the supply network. Additional conditions for improving of energy and efficiency performance of the compensator are considered: i.e. reactive power compensation. The compensator sizing algorithm was implemented into a MATLAB environment software, which generate the time-evolution of the parameters of load current symmetrization device. The input data of application takes into account time-recording of the electrical values. By using the compensator sizing software, some results were achieved for the case of a consumer connected at 20 kV busbar of a distribution substation, during 24 hours measurement session. Even the sizing of the compensators aimed some additional network operation aspects (power factor correction) correlated with the total or major load symmetrizations, the harmonics aspects of the network values were neglected.

  7. Duration of load revisited

    DEFF Research Database (Denmark)

    Hoffmeyer, Preben; Sørensen, John Dalsgaard

    2007-01-01

    were formed. Four groups were subjected to short-term strength tests, and four groups were subjected to long-term tests. Creep and time to failure were moni-tored. Time to failure as a function of stress level was established and the reliability of stress level assessment was discussed. A significant...... mechanosorptive effect was demonstrated both in terms of increased creep and shortening of time to failure. The test results were employed for the calibration of four existing duration of load models. The effect of long-term loading was expressed as the stress level SL50 to cause failure after 50 years of loading...... and of the short-term and long-term strengths. For permanent and imposed library loads, reliability-based estimation of the load duration factor gave almost the same results as direct, deterministic calibration. Keywords: Creep, damage models, duration of load, equal rank assumption, load duration factor, matched...

  8. Technique applied in electrical power distribution for Satellite Launch Vehicle

    Directory of Open Access Journals (Sweden)

    João Maurício Rosário

    2010-09-01

    Full Text Available The Satellite Launch Vehicle electrical network, which is currently being developed in Brazil, is sub-divided for analysis in the following parts: Service Electrical Network, Controlling Electrical Network, Safety Electrical Network and Telemetry Electrical Network. During the pre-launching and launching phases, these electrical networks are associated electrically and mechanically to the structure of the vehicle. In order to succeed in the integration of these electrical networks it is necessary to employ techniques of electrical power distribution, which are proper to Launch Vehicle systems. This work presents the most important techniques to be considered in the characterization of the electrical power supply applied to Launch Vehicle systems. Such techniques are primarily designed to allow the electrical networks, when submitted to the single-phase fault to ground, to be able of keeping the power supply to the loads.

  9. Large Scale Demand Response of Thermostatic Loads

    DEFF Research Database (Denmark)

    Totu, Luminita Cristiana

    This study is concerned with large populations of residential thermostatic loads (e.g. refrigerators, air conditioning or heat pumps). The purpose is to gain control over the aggregate power consumption in order to provide balancing services for the electrical grid. Without affecting...... the temperature limits and other operational constraints, and by using only limited communication, it is possible to make use of the individual thermostat deadband flexibility to step-up or step-down the power consumption of the population as if it were a power plant. The individual thermostatic loads experience...

  10. electric vehicle

    Directory of Open Access Journals (Sweden)

    W. R. Lee

    1999-01-01

    Full Text Available A major problem facing battery-powered electric vehicles is in their batteries: weight and charge capacity. Thus, a battery-powered electric vehicle only has a short driving range. To travel for a longer distance, the batteries are required to be recharged frequently. In this paper, we construct a model for a battery-powered electric vehicle, in which driving strategy is to be obtained such that the total travelling time between two locations is minimized. The problem is formulated as an optimization problem with switching times and speed as decision variables. This is an unconventional optimization problem. However, by using the control parametrization enhancing technique (CPET, it is shown that this unconventional optimization is equivalent to a conventional optimal parameter selection problem. Numerical examples are solved using the proposed method.

  11. FORECASTING ELECTRICITY PRICES IN DEREGULATED WHOLESALE SPOT ELECTRICITY MARKET - A REVIEW

    Directory of Open Access Journals (Sweden)

    Girish Godekere Panchakshara Murthy,

    2014-01-01

    Full Text Available In the new framework of competitive electricity markets, all power market participants need accurate price forecasting tools. Electricity price forecasts characterize significant information that can help captive power producer, independent power producer, power generation companies, power distribution companies or open access consumers in careful planning of their bidding strategies for maximizing their profits, benefits and utilities from long term, medium term and short term perspective. Short term spot electricity price forecasting techniques are either inspired from electrical engineering literature (i.e. load forecasting or from economics literature (i.e. game theory models and the time-series econometric models. In this study we investigate the emergence of spot electricity markets with particular emphasis on Indian electricity market which has never been done before and review selected finance and econometrics inspired literature and models for forecasting electricity spot prices in deregulated wholesale spot electricity markets.

  12. Improving the Model for Energy Consumption Load Demand Forecasting

    Science.gov (United States)

    Bunnoon, Pituk; Chalermyanont, Kusumal; Limsakul, Chusak

    This paper proposes an application of a filter method in preprocessing stage for mid-term load demand forecasting to improve electricity load forecasting and to guarantee satisfactory forecasting accuracy. Case study employs the historical electricity consumption demand data in Thailand which were recorded in the 12 years of 1997 through to 2007. The load demand forecasted value is used for unit commitment and fuel reserve planning in the power system. This method consists of a trend component and a cyclical component decomposed from the original load demand using the Hodrick-Prescott (HP) filter in the preprocessing stage and the forecasting of each component using Double Neural Networks (DNNs) in the forecasting stage. Experimental results show that with preprocessing before forecasting can predict the load demand better than that without preprocessing.

  13. Modeling spot markets for electricity and pricing electricity derivatives

    Science.gov (United States)

    Ning, Yumei

    Spot prices for electricity have been very volatile with dramatic price spikes occurring in restructured market. The task of forecasting electricity prices and managing price risk presents a new challenge for market players. The objectives of this dissertation are: (1) to develop a stochastic model of price behavior and predict price spikes; (2) to examine the effect of weather forecasts on forecasted prices; (3) to price electricity options and value generation capacity. The volatile behavior of prices can be represented by a stochastic regime-switching model. In the model, the means of the high-price and low-price regimes and the probabilities of switching from one regime to the other are specified as functions of daily peak load. The probability of switching to the high-price regime is positively related to load, but is still not high enough at the highest loads to predict price spikes accurately. An application of this model shows how the structure of the Pennsylvania-New Jersey-Maryland market changed when market-based offers were allowed, resulting in higher price spikes. An ARIMA model including temperature, seasonal, and weekly effects is estimated to forecast daily peak load. Forecasts of load under different assumptions about weather patterns are used to predict changes of price behavior given the regime-switching model of prices. Results show that the range of temperature forecasts from a normal summer to an extremely warm summer cause relatively small increases in temperature (+1.5%) and load (+3.0%). In contrast, the increases in prices are large (+20%). The conclusion is that the seasonal outlook forecasts provided by NOAA are potentially valuable for predicting prices in electricity markets. The traditional option models, based on Geometric Brownian Motion are not appropriate for electricity prices. An option model using the regime-switching framework is developed to value a European call option. The model includes volatility risk and allows changes

  14. Electric Backpack

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    @@ Backpacks are convenient. They can hold your books,your lunch,and a change of clothes,leaving your hands free to do other things. Someday,if you don't mind carrying a heavy load,your backpack might also power your MP3 player,keep your cell phone running,and maybe even light your way home.

  15. Systems and methods for providing power to a load based upon a control strategy

    Science.gov (United States)

    Perisic, Milun; Kajouke, Lateef A; Ransom, Ray M

    2013-12-24

    Systems and methods are provided for an electrical system. The electrical system includes a load, an interface configured to receive a voltage from a voltage source, and a controller configured to receive the voltage from the voltage source through the interface and to provide a voltage and current to the load. Wherein, when the controller is in a constant voltage mode, the controller provides a constant voltage to the load, when the controller is in a constant current mode, the controller provides a constant current to the load, and when the controller is in a constant power mode, the controller provides a constant power to the load.

  16. Modeling of the electric ship

    OpenAIRE

    2010-01-01

    Approved for public release; distribution is unlimited As the United States Navy continues to refine its designs for future ships, one approach that it is currently being explored is to use a unified electrical grid to power every system aboard a ship, including propulsion and weapons. Some concerns with this design are estimating the power demands placed upon the grid by various systems and anticipating transients induced on the grid by high power pulsed loads. The first part of this thes...

  17. Anchor Loads on Pipelines

    OpenAIRE

    Wei, Ying

    2015-01-01

    Anchor hooking on a subsea pipeline has been investigated in this thesis. Anchor loads on pipelines is in general a rarely occurring event, however, the severity when it occurs could easily jeopardize the integrity of any pipeline. It is considered as an accidental load in the design of pipelines. Pipeline Loads, limit state criteria and anchor categories are defined by the DNV standards. For pipeline, DNV-OS-F101 (08.2012), Submarine Pipeline Systems is adopted. Offshore standard DNV-RP...

  18. Load induced blindness

    OpenAIRE

    Macdonald, J. S. P.; Lavie, N.

    2008-01-01

    Although the perceptual load theory of attention has stimulated a great deal of research, evidence for the role of perceptual load in determining perception has typically relied oil indirect measures that infer perception from distractor effects on reaction times or neural activity (see N. Lavie, 2005. for a review). Here we varied the level of perceptual load in a letter-search task and assessed its effect oil the conscious perception of a search-irrelevant shape stimulus appearing in the pe...

  19. 浅谈大同推广应用智能电网技术--电能量采集和负荷管理系统%Discussion on Electric Energy Acquisition and Load Management System Which Is the Smart Grid Technology Promoted and Applied by Datong

    Institute of Scientific and Technical Information of China (English)

    冯立伟

    2015-01-01

    According to the"Twelve-Five"power marketing development plan of national grid company, Datong Power Supply Company speeds up the marketing modernization and measurement scientization construction, actively promotes the use of smart grid technology, vigorously implements the construction of electric energy acquisition and load management system in order to achieve the change from artificial remote meter reading to the automated meter reading, implement the techniques and services to electricity customers through modern management, and realize digital and fine marketing management based on the existing management platforms and technical conditions. These measures have important strategic significance for enhancing the company's power marketing automation and intelligence level.%根据国家电网公司“十二五”电力营销发展规划,大同供电公司加快营销现代化和计量科学化建设,积极推广应用智能电网技术,大力实施电能量采集和负荷管理系统的建设,实现由人工抄表到远程自动化抄表方式的转变,通过现代化技术将管理和服务落实到用电客户,基于现有的管理平台和技术条件,实现营销管理的数字化、精细化。对于提升公司电力营销自动化、智能化水平具有重要的战略意义。

  20. Concentrated loads on concrete

    DEFF Research Database (Denmark)

    Lorenzen, Karen Grøndahl; Nielsen, Mogens Peter

    1997-01-01

    This report deals with concentrated loads on concrete.A new upper bound solution in the axisymmetrical case of a point load in the center of the end face of a cylinder is developed.Based on previous work dealing with failure mechanisms and upper bound solutions, new approximate formulas are devel......This report deals with concentrated loads on concrete.A new upper bound solution in the axisymmetrical case of a point load in the center of the end face of a cylinder is developed.Based on previous work dealing with failure mechanisms and upper bound solutions, new approximate formulas...

  1. Concentrated loads on concrete

    DEFF Research Database (Denmark)

    Lorenzen, Karen Grøndahl; Nielsen, Mogens Peter

    1997-01-01

    This report deals with concentrated loads on concrete.A new upper bound solution in the axisymmetrical case of a point load in the center of the end face of a cylinder is developed.Based on previous work dealing with failure mechanisms and upper bound solutions, new approximate formulas are devel......This report deals with concentrated loads on concrete.A new upper bound solution in the axisymmetrical case of a point load in the center of the end face of a cylinder is developed.Based on previous work dealing with failure mechanisms and upper bound solutions, new approximate formulas...

  2. Critical Axial Load

    Directory of Open Access Journals (Sweden)

    Walt Wells

    2008-01-01

    Full Text Available Our objective in this paper is to solve a second order differential equation for a long, simply supported column member subjected to a lateral axial load using Heun's numerical method. We will use the solution to find the critical load at which the column member will fail due to buckling. We will calculate this load using Euler's derived analytical approach for an exact solution, as well as Euler's Numerical Method. We will then compare the three calculated values to see how much they deviate from one another. During the critical load calculation, it will be necessary to calculate the moment of inertia for the column member.

  3. Modeling of STATCOM under different loading conditions

    DEFF Research Database (Denmark)

    George, G.J.; Ramachandran, Rakesh; Kowsalya, M.

    2012-01-01

    This paper deals with the study and analysis of Flexible AC Transmission Systems (FACTS), mainly the modeling of STATCOM. Reactive Power Compensation plays a very important role in the transmission of Electric Power. A comparative study of how the reactive power is injected into the transmission ...... system with and without STATCOM under different loading condition is also illustrated in this paper. Simulations are performed using MATLAB/SIMULINK software. © 2012 IEEE....

  4. Stability Analysis of a Constant Power Load Serviced by a Buck Converter as the Source Impedance Varies

    Science.gov (United States)

    2012-09-01

    electric ships, being aware of the stability issues associated with direct current (DC)-DC and DC-alternating current (AC) power converters and... Electric vehicles FCV Fuel Cell Vehicle HEV Hybrid Electric Vehicle Hf Final Load Transfer Function Hf_vec Final Load Transfer Function...Voltage Law SL Source Inductance MEV More Electric Vehicle MVDC Medium Voltage DC xiv P Power OP Output Power Pof Final Power Level Poi

  5. High voltage load resistor array

    Energy Technology Data Exchange (ETDEWEB)

    Lehmann, Monty Ray [Smithfield, VA

    2005-01-18

    A high voltage resistor comprising an array of a plurality of parallel electrically connected resistor elements each containing a resistive solution, attached at each end thereof to an end plate, and about the circumference of each of the end plates, a corona reduction ring. Each of the resistor elements comprises an insulating tube having an electrode inserted into each end thereof and held in position by one or more hose clamps about the outer periphery of the insulating tube. According to a preferred embodiment, the electrode is fabricated from stainless steel and has a mushroom shape at one end, that inserted into the tube, and a flat end for engagement with the end plates that provides connection of the resistor array and with a load.

  6. Modelling grid losses and the geographic distribution of electricity generation

    DEFF Research Database (Denmark)

    Østergaard, Poul Alberg

    2005-01-01

    In Denmark more than 40% of the electricity consumption is covered by geographically scattered electricity sources namely wind power and local CHP (cogeneration of heat and power) plants. This causes problems in regard to load balancing and possible grid overloads. The potential grid problems...... and methods for solving these are analysed in this article on the basis of energy systems analyses, geographic distribution of consumption and production and grid load-flow analyses. It is concluded that by introducing scattered load balancing using local CHP plants actively and using interruptible loads...

  7. Electric Propulsion

    Science.gov (United States)

    Baggett, R.

    2004-11-01

    Next Generation Electric Propulsion (NGEP) technology development tasks are working towards advancing solar-powered electric propulsion systems and components to levels ready for transition to flight systems. Current tasks within NGEP include NASA's Evolutionary Xenon Thruster (NEXT), Carbon Based Ion Optics (CBIO), NSTAR Extended Life Test (ELT) and low-power Hall Effect thrusters. The growing number of solar electric propulsion options provides reduced cost and flexibility to capture a wide range of Solar System exploration missions. Benefits of electric propulsion systems over state-of-the-art chemical systems include increased launch windows, which reduce mission risk; increased deliverable payload mass for more science; and a reduction in launch vehicle size-- all of which increase the opportunities for New Frontiers and Discovery class missions. The Dawn Discovery mission makes use of electric propulsion for sequential rendezvous with two large asteroids (Vesta then Ceres), something not possible using chemical propulsion. NEXT components and thruster system under development have NSTAR heritage with significant increases in maximum power and Isp along with deep throttling capability to accommodate changes in input power over the mission trajectory. NEXT will produce engineering model system components that will be validated (through qualification-level and integrated system testing) and ready for transition to flight system development. NEXT offers Discovery, New Frontiers, Mars Exploration and outer-planet missions a larger deliverable payload mass and a smaller launch vehicle size. CBIO addresses the need to further extend ion thruster lifetime by using low erosion carbon-based materials. Testing of 30-cm Carbon-Carbon and Pyrolytic graphite grids using a lab model NSTAR thruster are complete. In addition, JPL completed a 1000 hr. life test on 30-cm Carbon-Carbon grids. The NSTAR ELT was a life time qualification test started in 1999 with a goal of 88 kg

  8. Optimisation models and solution methods for load management

    Energy Technology Data Exchange (ETDEWEB)

    Gustafsson, Stig-Inge [Linkoeping Univ. (Sweden). Div. of Wood Science and Technology; Roennqvist, Mikael; Claesson, Marcus [Linkoeping Univ. (Sweden). Div. of Optimisation

    2001-02-01

    The electricity market in Sweden has changed during recent years. Electricity for industrial use can nowadays be purchased from a number of competing electricity suppliers. Hence, the price for each kilowatt-hour is significantly lower than just two years ago and the interest for electricity conservation measures has declined. Part of the electricity tariff is, however, almost the same as before, i.e. the demand cost expressed in Swedish Kronor, SEK, for each kilowatt. This has put focus on load management measures in order to decrease this specific cost. Saving one kWh might lead to monetary savings between 0.22 to 914 SEK and this paper shows how to save only those kWh which really save money. A load management system has been installed in a small carpentry factory and the device can turn off equipment due to a certain priority and for a number of minutes each hour. The question is now, what level on the electricity load is optimal in a strict mathematical sense, i.e. how many kW should be set in the load management computer in order to get the best profitability? In this paper we develop a mathematical model which can be used both as a tool to find a best profitable subscription level and as a tool to control the turn of choices. Numerical results from a case study are presented.

  9. Optimal Load Dispatch Using Ant Lion Optimization

    Directory of Open Access Journals (Sweden)

    Menakshi Mahendru Nischal

    2015-08-01

    Full Text Available This paper presents Ant lion optimization (ALO technique to solve optimal load dispatch problem. Ant lion optimization (ALO is a novel nature inspired algorithm. The ALO algorithm mimics the hunting mechanism of ant lions in nature. Five main steps of hunting prey such as the random walk of ants, building traps, entrapment of ants in traps, catching preys, and re-building traps are implemented. Optimal load dispatch (OLD is a method of determining the most efficient, low-cost and reliable operation of a power system by dispatching available electricity generation resources to supply load on the system. The primary objective of OLD is to minimize total cost of generation while honoring operational constraints of available generation resources. The proposed technique is implemented on 3, 6 & 20 unit test system for solving the OLD. Numerical results shows that the proposed method has good convergence property and better in quality of solution than other algorithms reported in recent literature.

  10. Topics on electricity trade

    Energy Technology Data Exchange (ETDEWEB)

    Skytte, K.

    2001-07-01

    The first chapter in this thesis is a survey of studies on electricity trade, which has been included in order to show how subjects in this thesis fit into this aspect of energy research. Transitions from centralised monopolies to liberalised electricity markets have been inaugurated in the northern European countries during the last decade. The backgrounds and speed of transitions differ within the countries. Where Norway liberalised its electricity market in order to stabilise the prices, EU urged a liberalisation in order to make the electricity supply industry more effective. Together with national liberalisation, the opening of the cross border trade between the countries is also urged. The first paper in this thesis describes those different liberalisation processes within northern Europe and discusses problems that may arise in a transition period for integrating the countries into a common electricity market with efficient cross-border competition. Before the liberalisation process started, the electricity generation was determined by a central load dispatch at known prices. The introduction of competition has necessitated the creation of new competitive markets, power exchanges and financial markets where generation and prices are determined by demand and supply on the markets. One implication of this is that investments in new plants shall be made under levels of uncertainty about future prices. The second paper in this thesis analyses the importance of introducing uncertainty in energy-economic modelling of the electricity supply sector. Another implication, which arises on introducing a new market structure and power exchanges, is that the design of the power exchanges influences the price setting on the markets. The third paper of this thesis analyses the price setting on the regulating power market on the Nordic power exchange Nord Pool. More precisely, the paper reveals the pattern of the prices on the regulating power market by analysing the cost of

  11. Theories and technologies of electronic-electrical-mechanical integrated(EEMI)transmission system

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    @@ EEMI is one of the hot spots in cross-disciplinary research. The research in this topic was to discard the traditional mechanical gear reducer, integrate electrical motor with mechanical load, control the electrical motor by electrical power generated by microelectronics and electrical electronics; namely, form a EEMI transmission system in the mechanical equipments with low rotation rate and large rotation torque.

  12. Electrical Percolation Effect on Electromechanical Behavior of CNT Nanocomposites

    Directory of Open Access Journals (Sweden)

    Yves Ngabonziza

    2011-12-01

    Full Text Available Electrical resistance responses of multi-walled carbon nanotubes (MWCNT reinforced polypropylene (PP nanocomposites under mechanical tensile loading are studied in this paper. A standard tensile test was conducted while the electrical resistance was measured using 2-probe method. From our previous works on the CNT/PP nanocomposites, the percolation threshold of electrical conductivity is around 3.8 wt% of CNT. The influence of this percolation threshold on the electrical resistance upon mechanical loading was investigated. The results will be discussed and compared.

  13. Transient Thermoelectric Generator: An Active Load Story

    Science.gov (United States)

    Stockholm, J. G.; Goupil, C.; Maussion, P.; Ouerdane, H.

    2015-06-01

    Under stationary conditions, the optimization of maximum power output and efficiency of thermoelectric generators (TEG) is a well-known subject. Use of a finite-time thermodynamics (FTT) approach to the description of TEGs has demonstrated that there exists a closed feedback effect between the output electrical load value and the entering heat current. From the practical point of view, this effect is strongly evidenced by the use of direct current (DC-to-DC) converters as active loads. Both transient conditions and FTT contribute to a complex landscape of the optimization of the power and efficiencies of a TEG. It has been claimed that the use of inductive load may lead to a strong enhancement of the efficiency, and the frequency response of a TEG as a band-pass filter has also been recently reported. We consider these results using a classical linear Onsager approach of a TEG operating under transient conditions. We show that a trans-admittance may be defined as a coupling element between the input and the output, leading to the observed electric-to-thermal feedback. We discuss recent experiments on a TEG connected to an active load, which is reported to boast an efficiency exceeding the usual stationary DC thermoelectric efficiency.

  14. Preset Electrodes for Electrical-Discharge Machining

    Science.gov (United States)

    Coker, Bill E.

    1987-01-01

    New electrode holder for electrical-discharge machining (EDM) provides for repeatable loading and setting of many electrodes. New holder is rotating-index tool carrying six, eight, or more electrodes. Before use, all electrodes set with aid of ring surrounding tool, and locked in position with screws. When electrode replaced, EDM operator pulls spring-loaded pin on tool so it rotates about center pin. Fresh electrode then rotated into position against workpiece.

  15. Electric monopoly

    Energy Technology Data Exchange (ETDEWEB)

    Norton, C.

    1981-09-14

    A controversial proposal to deregulate a major part of the electric utility industry could transform how electric power is produced. The proposal involves one-third of US energy consumption and violates the classic economic theory that tightly regulated natural monopolies serve society's needs best. Supporters of the proposal suggest that free-market competition may now be valid because new technologies and new power-supply sources can introduce innovation and efficiency into cost control. Many states, for example, allow utilities to pass capital costs through to their users. Alternative energy sources could include small hydro, wind power, and industrial cogeneration. Opponents, who question whether there really is a free market in energy production, suggest better regulation to protect consumers. Some of the opposition will come from utilities wanting to keep their captive markets. (DCK)

  16. Electricity unplugged

    Science.gov (United States)

    Karalis, Aristeidis

    2009-02-01

    The judge was driving back late one cold winter night. Entering the garage, the battery-charging indicator in his wirelessly powered electric car came on. "Home at last," crossed his mind. He swiped his personal smartcard on the front-door detector to be let in. He heard a "charging" beep from his mobile phone. The blinking cursor on the half-finished e-mail on the laptop had been waiting all day on the side table. He picked the computer up and walked towards his desk. "Good evening, your honour. Your wirelessly heated robe," said the butler-robot as it approached from the kitchen. Putting on the electric garment, he sat on the medical desk chair. His artificial heart was now beating faster.

  17. Combination of external loads

    Energy Technology Data Exchange (ETDEWEB)

    Frandsen, S.; Tarp Johansen, N.J.; Joergensen, H. [Forskningscenter Risoe, Roskilde (Denmark); Gravesen, H.; Soerensen, S.L. [Carl Bro, Glostrup (Denmark); Pedersen, J. [Elsam Engineering, Fredericia (Denmark); Zorn, R.; Hvidberg Knudsen, M. [DHI Water and Environment, Hoersholm (Denmark); Voelund, P. [Energi E2, Koebenhavn (Denmark)

    2003-09-01

    The project onbectives have been: To improve and consequently opimise the basis for design of offshore wind turbines. This is done through 1) mapping the wind, wave ice and current as well as correlations of these, and 2) by clarifyring how these external conditions transform into loads. A comprehensive effort has been made to get a thorough understanding of the uncertainties that govern the reliability of wind turbines with respect to wind and wave loading. One of the conclusions is that the reliability of wind turbines is generally lower, than the average reliability of building structures that are subject not only to environmental loads, which are very uncertain, but also imposed loads and self weight, which are less uncertain than the environmental loads. The implication is that, at the moment lower load partial safety factors for onshore wind turbines cannot be recommended. For the combination of wind and wave design loads the problem is twofold: 1). A very conservative design will be generated by simply adding the individual wind and wave design loads disregarding the independence of the short-term fluctuations of wind and wave loads. 2). Characteristic values and partial safety factors for wind and wave loads are not defined similarly. This implies that the reliability levels of turbine support structures subject to purely aerodynamic loads and subject to purely hydrodynamic loads are not identical. For the problem of combining aerodynamic design loads and hydrodynamic design loads two results have been obtained in the project: 1). By simple means a site specific wave load safety factor rendering the same safety level for hydrodynamic loads as for aerodynamic loads is derived, and next, by direct square summation of extreme fluctuations, the wind and wave load safety factors are weighted. 2). Under the assumptions that a deep water site is considered and that the wave loading is a fifty-fifty mix of drag and inertia the same wind and wave load safety factor

  18. Load Induced Blindness

    Science.gov (United States)

    Macdonald, James S. P.; Lavie, Nilli

    2008-01-01

    Although the perceptual load theory of attention has stimulated a great deal of research, evidence for the role of perceptual load in determining perception has typically relied on indirect measures that infer perception from distractor effects on reaction times or neural activity (see N. Lavie, 2005, for a review). Here we varied the level of…

  19. Electric Car

    Science.gov (United States)

    1977-01-01

    NASA's Lewis Research Center undertook research toward a practical, economical battery with higher energy density. Borrowing from space satellite battery technology, Lewis came up with a nickel-zinc battery that promises longer life and twice the range of the lead-acid counterpart. Lewis researchers fabricated a prototype battery and installed it in an Otis P-500 electric utility van, using only the battery space already available and allowing battery weight equal to that of the va's conventional lead-acid battery

  20. INDIA’S ELECTRICITY DEMAND FORECAST USING REGRESSION ANALYSIS AND ARTIFICIAL NEURAL NETWORKS BASED ON PRINCIPAL COMPONENTS

    OpenAIRE

    Saravanan, S; Kannan, S.; C. Thangaraj

    2012-01-01

    Power System planning starts with Electric load (demand) forecasting. Accurate electricity load forecasting is one of the most important challenges in managing supply and demand of the electricity, since the electricity demand is volatile in nature; it cannot be stored and has to be consumed instantly. The aim of this study deals with electricity consumption in India, to forecast future projection of demand for a period of 19 years from 2012 to 2030. The eleven input variables used are Amount...

  1. Indentation load relaxation test

    Energy Technology Data Exchange (ETDEWEB)

    Hannula, S.P.; Stone, D.; Li, C.Y. (Cornell Univ., Ithaca, NY (USA))

    Most of the models that are used to describe the nonelastic behavior of materials utilize stress-strain rate relations which can be obtained by a load relaxation test. The conventional load relaxation test, however, cannot be performed if the volume of the material to be tested is very small. For such applications the indentation type of test offers an attractive means of obtaining data necessary for materials characterization. In this work the feasibility of the indentation load relaxation test is studied. Experimental techniques are described together with results on Al, Cu and 316 SS. These results are compared to those of conventional uniaxial load relaxation tests, and the conversion of the load-indentation rate data into the stress-strain rate data is discussed.

  2. Regression based peak load forecasting using a transformation technique

    Energy Technology Data Exchange (ETDEWEB)

    Haida, Takeshi; Muto, Shoichi (Tokyo Electric Power Co. (Japan). Computer and Communication Research Center)

    1994-11-01

    This paper presents a regression based daily peak load forecasting method with a transformation technique. In order to forecast the load precisely through a year, the authors should consider seasonal load change, annual load growth and the latest daily load change. To deal with these characteristics in the load forecasting, a transformation technique is presented. This technique consists of a transformation function with translation and reflection methods. The transformation function is estimated with the previous year's data points, in order that the function converts the data points into a set of new data points with preserving the shape of temperature-load relationships in the previous year. Then, the function is slightly translated so that the transformed data points will fit the shape of temperature-load relationships in the year. Finally, multivariate regression analysis with the latest daily loads and weather observations estimates the forecasting model. Large forecasting errors caused by the weather-load nonlinear characteristic in the transitional seasons such as spring and fall are reduced. Performance of the technique which is verified with simulations on actual load data of Tokyo Electric Power Company is also described.

  3. Integration of electric drive vehicles in the Danish electricity network with high wind power penetration

    DEFF Research Database (Denmark)

    Chandrashekhara, Divya K; Østergaard, Jacob; Larsen, Esben

    2010-01-01

    /conventional) which are likely to fuel these cars. The study was carried out considering the Danish electricity network state around 2025, when the EDV penetration levels would be significant enough to have an impact on the power system. Some of the interesting findings of this study are - EDV have the potential......This paper presents the results of a study carried out to examine the feasibility of integrating electric drive vehicles (EDV) in the Danish electricity network which is characterised by high wind power penetration. One of the main aims of this study was to examine the effect of electric drive...... vehicles on the Danish electricity network, wind power penetration and electricity market. In particular the study examined the effect of electric drive vehicles on the generation capacity constraints, load curve, cross border transmission capacity and the type of generating sources (renewable...

  4. Unsupervised/supervised learning concept for 24-hour load forecasting

    Energy Technology Data Exchange (ETDEWEB)

    Djukanovic, M. (Electrical Engineering Inst. ' Nikola Tesla' , Belgrade (Yugoslavia)); Babic, B. (Electrical Power Industry of Serbia, Belgrade (Yugoslavia)); Sobajic, D.J.; Pao, Y.-H. (Case Western Reserve Univ., Cleveland, OH (United States). Dept. of Electrical Engineering and Computer Science)

    1993-07-01

    An application of artificial neural networks in short-term load forecasting is described. An algorithm using an unsupervised/supervised learning concept and historical relationship between the load and temperature for a given season, day type and hour of the day to forecast hourly electric load with a lead time of 24 hours is proposed. An additional approach using functional link net, temperature variables, average load and last one-hour load of previous day is introduced and compared with the ANN model with one hidden layer load forecast. In spite of limited available weather variables (maximum, minimum and average temperature for the day) quite acceptable results have been achieved. The 24-hour-ahead forecast errors (absolute average) ranged from 2.78% for Saturdays and 3.12% for working days to 3.54% for Sundays. (Author)

  5. Voltage stability dynamical analysis by comparing static and dynamical loads; Estudio dinamico de estabilidad de tension comparando modelos de carga estatica y carga dinamica

    Energy Technology Data Exchange (ETDEWEB)

    Aromataris, Luis [Universidad Nacional de Rio Cuarto (UNRC) (Argentina); Arnera, Patricia; Riubrugent, Jean [Universidad Nacional de La Plata, Buenos Aires (Argentina). Facultad de Ingenieria. Instituto de Investigaciones Tecnologicas para Redes y Equipos Electricos

    2001-07-01

    This work investigate the impact produced by the load model on the voltage stability analysis of an electric system. Qualitative and quantitative analyses are approached in connection with the effects of modeling the electric loads by both dynamical and static way. Also it is highlighted the importance of using dynamical models of load, mainly when it is composed by motors.

  6. Activation energy of the low-load NaCl transition from nanoindentation loading curves.

    Science.gov (United States)

    Kaupp, Gerd

    2014-01-01

    Access to activation energies E(a) of phase transitions is opened by unprecedented analyses of temperature dependent nanoindentation loading curves. It is based on kinks in linearized loading curves, with additional support by coincidence of kink and electrical conductivity of silicon loading curves. Physical properties of B1, B2, NaCl and further phases are discussed. The normalized low-load transition energy of NaCl (Wtrans/µN) increases with temperature and slightly decreases with load. Its semi-logarithmic plot versus T obtains activation energy E(a)/µN for calculation of the transition work for all interesting temperatures and pressures. Arrhenius-type activation energy (kJ/mol) is unavailable for indentation phase transitions. The E(a) per load normalization proves insensitive to creep-on-load, which excludes normalization to depth or volume for large temperature ranges. Such phase transition E(a)/µN is unprecedented material's property and will be of practical importance for the compatibility of composite materials under impact and further shearing interactions at elevated temperatures.

  7. Artificial Intelligence for Load Management Based On Load Shifting in the Textile Industry

    Directory of Open Access Journals (Sweden)

    Chaimongkon Chokpanyasuwan

    2015-02-01

    Full Text Available The target of any load management is to maintain a constant level of load. The important benefits of load management are reduction in maximum demand, reduction in power loss, better equipment utilization and saving through reduced maximum demand charges. Load shifting, one of the simplest methods of load management, is to reduce customer demand during the peak period by shifting the use of appliances and equipment to partial peak and on-peak periods. This paper proposes an application of artificial intelligent (AI optimization methods i.e. genetic algorithm (GA, particle swarm optimization (PSO and bee algorithm (BA to develop the load shifting and the same has been tried with the actual load data collected from the textile industry plant. The objective is to minimize the total electricity tariff cost. The methodology proposed can be used for determining the optimal response for textile industry under time varying tariffs such as flat rate and time of use (TOU.To show its efficiency, the AI methods are applied to solve the case studies in case of single process multi-jobs (SPMJ. The results show that the proposed methods are able to achieve the best solution efficiently and easy to implement.

  8. Shuttle Electrical Power Analysis Program (SEPAP) distribution circuit analysis report

    Science.gov (United States)

    Torina, E. M.

    1975-01-01

    An analysis and evaluation was made of the operating parameters of the shuttle electrical power distribution circuit under load conditions encountered during a normal Sortie 2 Mission with emphasis on main periods of liftoff and landing.

  9. Computation of loss allocation in electric power networks using loss ...

    African Journals Online (AJOL)

    Computation of loss allocation in electric power networks using loss vector. ... The losses to be allocated are derived from load flow of a specified power network and operating conditions. Loss vectors associated with demand ... Article Metrics.

  10. Peak load arrangements : Assessment of Nordel guidelines

    Energy Technology Data Exchange (ETDEWEB)

    2009-07-01

    Two Nordic countries, Sweden and Finland, have legislation that empowers the TSO to acquire designated peak load resources to mitigate the risk for shortage situations during the winter. In Denmark, the system operator procures resources to maintain a satisfactory level of security of supply. In Norway the TSO has set up a Regulation Power Option Market (RKOM) to secure a satisfactory level of operational reserves at all times, also in winter with high load demand. Only the arrangements in Finland and Sweden fall under the heading of Peak Load Arrangements defined in Nordel Guidelines. NordREG has been invited by the Electricity Market Group (EMG) to evaluate Nordel's proposal for 'Guidelines for transitional Peak Load Arrangements'. The EMG has also financed a study made by EC Group to support NordREG in the evaluation of the proposal. The study has been taken into account in NordREG's evaluation. In parallel to the EMG task, the Swedish regulator, the Energy Markets Inspectorate, has been given the task by the Swedish government to investigate a long term solution of the peak load issue. The Swedish and Finnish TSOs have together with Nord Pool Spot worked on finding a harmonized solution for activation of the peak load reserves in the market. An agreement accepted by the relevant authorities was reached in early January 2009, and the arrangement has been implemented since 19th January 2009. NordREG views that the proposed Nordel guidelines have served as a starting point for the presently agreed procedure. However, NordREG does not see any need to further develop the Nordel guidelines for peak load arrangements. NordREG agrees with Nordel that the market should be designed to solve peak load problems through proper incentives to market players. NordREG presumes that the relevant authorities in each country will take decisions on the need for any peak load arrangement to ensure security of supply. NordREG proposes that such decisions should be

  11. Load Balancing Scientific Applications

    Energy Technology Data Exchange (ETDEWEB)

    Pearce, Olga Tkachyshyn [Texas A & M Univ., College Station, TX (United States)

    2014-12-01

    The largest supercomputers have millions of independent processors, and concurrency levels are rapidly increasing. For ideal efficiency, developers of the simulations that run on these machines must ensure that computational work is evenly balanced among processors. Assigning work evenly is challenging because many large modern parallel codes simulate behavior of physical systems that evolve over time, and their workloads change over time. Furthermore, the cost of imbalanced load increases with scale because most large-scale scientific simulations today use a Single Program Multiple Data (SPMD) parallel programming model, and an increasing number of processors will wait for the slowest one at the synchronization points. To address load imbalance, many large-scale parallel applications use dynamic load balance algorithms to redistribute work evenly. The research objective of this dissertation is to develop methods to decide when and how to load balance the application, and to balance it effectively and affordably. We measure and evaluate the computational load of the application, and develop strategies to decide when and how to correct the imbalance. Depending on the simulation, a fast, local load balance algorithm may be suitable, or a more sophisticated and expensive algorithm may be required. We developed a model for comparison of load balance algorithms for a specific state of the simulation that enables the selection of a balancing algorithm that will minimize overall runtime.

  12. Impact of Smart Grid Technologies on Peak Load to 2050

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-07-01

    The IEA's Smart Grids Technology Roadmap identified five global trends that could be effectively addressed by deploying smart grids. These are: increasing peak load (the maximum power that the grid delivers during peak hours), rising electricity consumption, electrification of transport, deployment of variable generation technologies (e.g. wind and solar PV) and ageing infrastructure. Along with this roadmap, a new working paper -- Impact of Smart Grid Technologies on Peak Load to 2050 -- develops a methodology to estimate the evolution of peak load until 2050. It also analyses the impact of smart grid technologies in reducing peak load for four key regions; OECD North America, OECD Europe, OECD Pacific and China. This working paper is a first IEA effort in an evolving modelling process of smart grids that is considering demand response in residential and commercial sectors as well as the integration of electric vehicles.

  13. Climate Action Benefits: Electricity

    Science.gov (United States)

    This page provides background on the relationship between electricity and climate change and describes what the CIRA Electricity analyses cover. It provides links to the subsectors Electricity Demand and Electricity Supply.

  14. Electrically switched ion exchange

    Energy Technology Data Exchange (ETDEWEB)

    Lilga, M.A. [Pacific Northwest National Lab., Richland, WA (United States); Schwartz, D.T.; Genders, D.

    1997-10-01

    A variety of waste types containing radioactive {sup 137}Cs are found throughout the DOE complex. These waste types include water in reactor cooling basins, radioactive high-level waste (HLW) in underground storage tanks, and groundwater. Safety and regulatory requirements and economics require the removal of radiocesium before these wastes can be permanently disposed of. Electrically Switched Ion Exchange (ESIX) is an approach for radioactive cesium separation that combines IX and electrochemistry to provide a selective, reversible, and economic separation method that also produces little or no secondary waste. In the ESIX process, an electroactive IX film is deposited electrochemically onto a high-surface area electrode, and ion uptake and elution are controlled directly by modulating the potential of the film. For cesium, the electroactive films under investigation are ferrocyanides, which are well known to have high selectivities for cesium in concentrated sodium solutions. When a cathode potential is applied to the film, Fe{sup +3} is reduced to the Fe{sup +2} state, and a cation must be intercalated into the film to maintain charge neutrality (i.e., Cs{sup +} is loaded). Conversely, if an anodic potential is applied, a cation must be released from the film (i.e., Cs{sup +} is unloaded). Therefore, to load the film with cesium, the film is simply reduced; to unload cesium, the film is oxidized.

  15. Solar Electricity

    Science.gov (United States)

    1988-01-01

    ARCO Solar manufactures PV Systems tailored to a broad variety of applications. PV arrays are routinely used at remote communications installations to operate large microwave repeaters, TV and radio repeaters rural telephone, and small telemetry systems that monitor environmental conditions. Also used to power agricultural water pumping systems, to provide electricity for isolated villages and medical clinics, for corrosion protection for pipelines and bridges, to power railroad signals, air/sea navigational aids, and for many types of military systems. ARCO is now moving into large scale generation for utilities.

  16. Electrical Power Distribution and Control Modeling and Analysis

    Science.gov (United States)

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

    2001-01-01

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

  17. Opportunities for electrical efficiency in the meat processing industry

    Energy Technology Data Exchange (ETDEWEB)

    Chow, A.T.

    1991-01-16

    A study was carried out to assess the potential of improving energy efficiency in the meat processing industry, by means of a survey. It was found that opportunities for improving electrical efficiency include: heat recovery from refrigeration compressors for hot water and space heating; better insulation in cold spaces to reduce refrigeration load; load shifting electric water heaters to reduce maximum demand; efficient lighting in cold spaces; and electric stimulation of beef to reduce refrigerated aging time by up to 50%. The independent meat processors were very interested in opportunities for improving electrical efficiency, and with ca 100 meat processors in Ontario, total estimated load reduction is estimated at 480 kW, and electrical consumption can be reduced by ca 2,550 MWh each year. 24 figs., 3 tabs.

  18. 驱动大惯量低刚度负载的推力矢量控制电动伺服机构的μ综合鲁棒控制%μ Synthesis Robust Control of Thrust Vector Control Electric Servo Mechanism Driving Large Inertia and Low Stiffness Load

    Institute of Scientific and Technical Information of China (English)

    陆豪; 李运华; 田胜利; 陈建涛

    2011-01-01

    Addressing on the uncertainty problems resulting from the parametric perturbation and the modeling error existing in the electric servo mechanism, the robust control technology for a class of electric servo mechanism used to drive the load with large inertia and low stiffness in aircrafts is researched via μ synthesis theory. For this class of electric servo mechanism, modeling according to one-DOF system will bring about big deviation. In order solving the problem, its two-DOF mathematic model is built by analyzing the dynamic characteristic of thrust vector control electric servo mechanism. Aiming at the performance requirements of controlled plant in position command tracking and torque disturbance restraint, theμ synthesis controller is designed by managing parametric perturbation and modeling error, whereas an optimization design method of weighting functions is put forward. The closed-loop system with μ synthesis controller in the normal case and the positive & negative perturbations is simulated by using MATLAB software, and its control performances are researched and compared with the performances of H∞ controller. The simulation results show that for this class of servo mechanism, the μ synthesis controller can effectively improve the conservative results of H∞ controller with condition of selecting the same weighting functions, and can make the closed-loop system not only have preferable performance robustness but also satisfy the requirements of dynamic performance targets for controlling system. The proposed optimization design method of weighting functions is good for the application of robust control technology in engineering field.%针对电动伺服机构存在的由参数摄动和建模误差引起的不确定性问题,应用μ综合理论研究一类用于驱动大惯量、低刚度负载的飞行器电动伺服机构的鲁棒控制技术.为了解决该类电动伺服机构按照单自由度系统建模会产生较大偏差的问题,通

  19. Modular load flow for restructured power systems

    CERN Document Server

    Hariharan, M V; Gupta, Pragati P

    2016-01-01

    In the subject of power systems, authors felt that a re-look is necessary at some conventional methods of analysis. In this book, the authors have subjected the time-honoured load flow to a close scrutiny. Authors have discovered and discussed a new load flow procedure – Modular Load Flow. Modular Load Flow explores use of power – a scalar – as source for electrical circuits which are conventionally analysed by means of phasors – the ac voltages or currents. The method embeds Kirchhoff’s circuit laws as topological property into its scalar equations and results in a unique wonderland where phase angles do not exist! Generators are shown to have their own worlds which can be superimposed to obtain the state of the composite power system. The treatment is useful in restructured power systems where stakeholders and the system operators may desire to know individual generator contributions in line flows and line losses for commercial reasons. Solution in Modular Load Flow consists of explicit expression...

  20. 2006 Pacific Northwest Loads and Resources Study.

    Energy Technology Data Exchange (ETDEWEB)

    United States. Bonneville Power Administration.

    2006-03-01

    The Pacific Northwest Loads and Resources Study (White Book), which is published annually by the Bonneville Power Administration (BPA), establishes one of the planning bases for supplying electricity to customers. The White Book contains projections of regional and Federal system load and resource capabilities, along with relevant definitions and explanations. The White Book also contains information obtained from formalized resource planning reports and data submittals including those from individual utilities, the Northwest Power and Conservation Council (Council), and the Pacific Northwest Utilities Conference Committee (PNUCC). The White Book is not an operational planning guide, nor is it used for determining BPA revenues, although the database that generates the data for the White Book analysis contributes to the development of BPA's inventory and ratemaking processes. Operation of the Federal Columbia River Power System (FCRPS) is based on a set of criteria different from that used for resource planning decisions. Operational planning is dependent upon real-time or near-term knowledge of system conditions that include expectations of river flows and runoff, market opportunities, availability of reservoir storage, energy exchanges, and other factors affecting the dynamics of operating a power system. The load resource balance of both the Federal system and the region is determined by comparing resource availability to an expected level of total retail electricity consumption. Resources include projected energy capability plus contract purchases. Loads include a forecast of retail obligations plus contract obligations. Surplus energy is available when resources are greater than loads. This surplus energy could be marketed to increase revenues. Energy deficits occur when resources are less than loads. These energy deficits will be met by any combination of the following: better-than-critical water conditions, demand-side management and conservation

  1. Peak loads and network investments in sustainable energy transitions

    Energy Technology Data Exchange (ETDEWEB)

    Blokhuis, Erik, E-mail: e.g.j.blokhuis@tue.nl [Eindhoven University of Technology, Department of Architecture, Building and Planning, Vertigo 8.11, P.O. Box 513, 5600MB Eindhoven (Netherlands); Brouwers, Bart [Eindhoven University of Technology, Department of Architecture, Building and Planning, Vertigo 8.11, P.O. Box 513, 5600MB Eindhoven (Netherlands); Putten, Eric van der [Endinet, Gas and Electricity Network Operations, P.O. Box 2005, 5600CA Eindhoven (Netherlands); Schaefer, Wim [Eindhoven University of Technology, Department of Architecture, Building and Planning, Vertigo 8.11, P.O. Box 513, 5600MB Eindhoven (Netherlands)

    2011-10-15

    Current energy distribution networks are often not equipped for facilitating expected sustainable transitions. Major concerns for future electricity networks are the possibility of peak load increases and the expected growth of decentralized energy generation. In this article, we focus on peak load increases; the effects of possible future developments on peak loads are studied, together with the consequences for the network. The city of Eindhoven (the Netherlands) is used as reference city, for which a scenario is developed in which the assumed future developments adversely influence the maximum peak loads on the network. In this scenario, the total electricity peak load in Eindhoven is expected to increase from 198 MVA in 2009 to 591-633 MVA in 2040. The necessary investments for facilitating the expected increased peak loads are estimated at 305-375 million Euros. Based upon these projections, it is advocated that - contrary to current Dutch policy - choices regarding sustainable transitions should be made from the viewpoint of integral energy systems, evaluating economic implications of changes to generation, grid development, and consumption. Recently applied and finished policies on energy demand reduction showed to be effective; however, additional and connecting policies on energy generation and distribution should be considered on short term. - Highlights: > Sustainable energy transitions can result in major electricity peak load increases. > Introduction of heat pumps and electrical vehicles requires network expansion. > Under worst case assumptions, peak loads in Eindhoven increase with 200% until 2040. > The necessary investment for facilitating this 2040 peak demand is Euro 305-375 million. > Future policy choices should be made from the viewpoint of the integral energy system.

  2. Propagation along azimuthally magnetized ferrite-loaded circular waveguides

    Science.gov (United States)

    Mueller, R. S.; Rosenbaum, F. J.

    1977-01-01

    The paper describes the modal dispersion characteristics of electromagnetic waves traveling along the azimuthally magnetized ferrite-loaded coaxial transmission line and the ferrite-loaded wire. The modal dispersion curves are used to determine the pass and stop bands of normal propagation. Boundary-value problems were solved with Bolle-Heller functions. The dispersion characteristics of transverse electric modes are presented as plots of the normalized propagation constant vs the normalized frequency.

  3. Load curves of industrial consumers: aggregation with other loads; Curvas de carga de consumidores industriais - agregacao com outras cargas

    Energy Technology Data Exchange (ETDEWEB)

    Casolari, Ronaldo Pedro; Jardini, Jose Antonio

    1996-07-01

    This work presents a methodology for load curves of industrial consumers, considering voltages up to 13.8 kV and inclusive. Initially, load curves representing the most significant activities were obtained, by performing a research of the industrial consumers from a survey of consumers and the respective month basis electric power consumption. The analysis similarity among the curves of various activities was conducted without using of any appropriated software, in accordance with the results obtained from the study of the commercial area. A computer program was developed for the determination of the expected loading in primary transformers and feeders, from representative curves and the month basis consumption of the consumers connected to those systems, considering the residential, commercial and industrial sectors. The test of the proposed methodology, for evaluation of loading of transformers and feeders, was performed by comparing the obtained curves with the measurements conducted by the electric power utilities in a transformer and a feeder.

  4. Electric-Drive Vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Septon, Kendall K [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-09-11

    Electric-drive vehicles use electricity as their primary fuel or to improve the efficiency of conventional vehicle designs. These vehicles can be divided into three categories: Hybrid electric vehicles (HEVs), Plug-in hybrid electric vehicles (PHEVs), All-electric vehicles (EVs). Together, PHEVs and EVs can also be referred to as plug-in electric vehicles (PEVs).

  5. Lumbriculus variegatus loading study

    Data.gov (United States)

    U.S. Environmental Protection Agency — Results from sediment bioaccumulation tests with Lumbriculus variegatus with evaluating the effects of organism loading density. This dataset is associated with the...

  6. Carbohydrate-Loading Diet

    Science.gov (United States)

    ... Grape juice (12 ounces) 55 225 Lunch Milk, chocolate, reduced fat (12 ounces) 45 285 4 slices ... of carb-loading for sports performance. Academy of Nutrition and Dietetics. http://www.eatright.org/resource/fitness/ ...

  7. LOADING SIMULATION PROGRAM C

    Data.gov (United States)

    U.S. Environmental Protection Agency — LSPC is the Loading Simulation Program in C++, a watershed modeling system that includes streamlined Hydrologic Simulation Program Fortran (HSPF) algorithms for...

  8. Cognitive load theory

    NARCIS (Netherlands)

    Kirschner, Paul A.; Kirschner, Femke; Paas, Fred

    2010-01-01

    Kirschner, P. A., Kirschner, F. C., & Paas, F. (2009). Cognitive load theory. In E. M. Anderman & L. H. Anderman (Eds.). Psychology of classroom learning: An encyclopedia, Volume 1, a-j (pp. 205-209). Detroit, MI: Macmillan Reference.

  9. Static Loads Test Facility

    Data.gov (United States)

    Federal Laboratory Consortium — FUNCTION: Provides the capability to perform large-scale structural loads testing on spacecraft and other structures. Results from these tests can be used to verify...

  10. Plug Load Data

    Data.gov (United States)

    National Aeronautics and Space Administration — We provide MATLAB binary files (.mat) and comma separated values files of data collected from a pilot study of a plug load management system that allows for the...

  11. Traffic modelling framework for electric vehicles

    Science.gov (United States)

    Schlote, Arieh; Crisostomi, Emanuele; Kirkland, Stephen; Shorten, Robert

    2012-07-01

    This article reviews and improves a recently proposed model of road network dynamics. The model is also adapted and generalised to represent the patterns of battery consumption of electric vehicles travelling in the road network. Simulations from the mobility simulator SUMO are given to support and to illustrate the efficacy of the proposed approach. Applications relevant in the field of electric vehicles, such as optimal routing and traffic load control, are provided to illustrate how the proposed model can be used to address typical problems arising in contemporary road network planning and electric vehicle mobility.

  12. Analysis of Electricity Consumption for Industrial Consumers

    Directory of Open Access Journals (Sweden)

    Marius Constantin Georgescu

    2016-10-01

    Full Text Available This paper presents a case study regarding the analysis of electricity consumption for a slaughter house as industrial consumer. This analysis takes into consideration the load curves during a whole year time delay. Based on data processing statistical methods within this case study, the author develops a forecasting procedure with time series analysis in order to better estimate the electricity consumption during a year. For the considered consumer, continuous supplied all the day by two power delivery networks of 20kV by means of an electrical transformer, practical results have been considered in order to verify the accuracy of statistical analysis.

  13. Using the internet of things to enable electrical load optimisation

    CSIR Research Space (South Africa)

    Butgereit, L

    2012-05-01

    Full Text Available . When a Resource Adaptor receives a message, it converts the message to a common format and forwards it to the Beachcomber routing facility. The routing facility refers to configuration tables and forwards the information to a... business process. The business processes are implemented as Mobicents Service Building Blocks (SBBs). These SBBs process the information and then send replies back to the routing facility which then forwards the replies to one or more...

  14. Neuromuscular impairment following backpack load carriage.

    Science.gov (United States)

    Blacker, Sam D; Fallowfield, Joanne L; Bilzon, James L J; Willems, Mark E T

    2013-01-01

    Load Carriage using backpacks is an occupational task and can be a recreational pursuit. The aim of this study was to investigate the mechanisms responsible for changes in neuromuscular function of the m. quadriceps femoris following load carriage. The physiological responses of 10 male participants to voluntary and electrically stimulated isometric contractions were measured before and immediately after two hours of treadmill walking at 6.5 km•h(-1) during level walking with no load [LW], and level walking with load carriage (25 kg backpack) [LC]. Maximal voluntary contraction force decreased by 15 ± 11 % following LC (p=0.006), with no change following LW (p=0.292). Voluntary activation decreased after LW and LC (p=0.033) with no difference between conditions (p=0.405). Doublet contraction time decreased after both LW and LC (p=0.002), with no difference between conditions (p=0.232). There were no other changes in electrically invoked doublet parameters in either condition. The 20:50 Hz ratio did not change following LW (p=0.864) but decreased from 0.88 ± 0.04 to 0.84 ± 0.04 after LC (p=0.011) indicating reduced Ca2+ release from the sarcoplasmic reticulum during excitation contraction coupling. In conclusion, two hours of load carriage carrying a 25 kg back pack caused neuromuscular impairment through a decrease in voluntary activation (i.e. central drive) and fatigue or damage to the peripheral muscle, including impairment of the excitation contraction coupling process. This may reduce physical performance and increase the risk of musculoskeletal injury.

  15. Electricity Demand and Energy Consumption Management System

    CERN Document Server

    Sarmiento, Juan Ojeda

    2008-01-01

    This project describes the electricity demand and energy consumption management system and its application to the Smelter Plant of Southern Peru. It is composted of an hourly demand-forecasting module and of a simulation component for a plant electrical system. The first module was done using dynamic neural networks, with backpropagation training algorithm; it is used to predict the electric power demanded every hour, with an error percentage below of 1%. This information allows management the peak demand before this happen, distributing the raise of electric load to other hours or improving those equipments that increase the demand. The simulation module is based in advanced estimation techniques, such as: parametric estimation, neural network modeling, statistic regression and previously developed models, which simulates the electric behavior of the smelter plant. These modules allow the proper planning because it allows knowing the behavior of the hourly demand and the consumption patterns of the plant, in...

  16. Loads as a Resource: Frequency Responsive Demand

    Energy Technology Data Exchange (ETDEWEB)

    Kalsi, Karanjit [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Williams, Tess L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Marinovici, Laurentiu D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Elizondo, Marcelo A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Lian, Jianming [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-11-30

    Demand-side frequency control can complement traditional generator controls to maintain the stability of large electric systems in the face of rising uncertainty and variability associated with renewable energy resources. This report presents a hierarchical frequency-based load control strategy that uses a supervisor to flexibly adjust control gains that a population of end-use loads respond to in a decentralized manner to help meet the NERC BAL-003-1 frequency response standard at both the area level and interconnection level. The load model is calibrated and used to model populations of frequency-responsive water heaters in a PowerWorld simulation of the U.S. Western Interconnection (WECC). The proposed design is implemented and demonstrated on physical water heaters in a laboratory setting. A significant fraction of the required frequency response in the WECC could be supplied by electric water heaters alone at penetration levels of less than 15%, while contributing to NERC requirements at the interconnection and area levels.

  17. Optimal Operation of Electric Vehicles in Competitive Electricity Markets and Its Impact on Distribution Power Systems

    DEFF Research Database (Denmark)

    Hu, Weihao; Chen, Zhe; Bak-Jensen, Birgitte

    2011-01-01

    operation strategy for a Plug-In Electric Vehicle (PEV) in relation to the hourly electricity price in order to achieve minimum energy costs of the PEV. The western Danish power system, which is currently the grid area in the world that has the largest share of wind power in its generation profiles and may...... represent the future of electricity markets in some ways, is chosen as the studied power system in this paper. The impact of the optimal operation strategy for electric vehicles together with the optimal load response to spot market price on the distribution power system with high wind power penetrations......Since the hourly spot market price is available one day ahead in Denmark, the electricity price could be transferred to the consumers and they may make some optimal charge and discharge schedules for their electric vehicles in order to minimize their energy costs. This paper presents an optimal...

  18. Thermal energy storage for electricity-driven space heating in a day-ahead electricity market

    DEFF Research Database (Denmark)

    Pensini, Alessandro

    2012-01-01

    Thermal Energy Storage (TES) in a space heating (SH) application was investigated. The study aimed to determine the economic benefits of introducing TES into an electricity-driven SH system under a day-ahead electricity market. The performance of the TES was assessed by comparing the cost...... of electricity in a system with a TES unit to the case where no storage is in use and the entire heat requirement is fulfilled by purchasing electricity according to the actual load. The study had two goals: 1. Determining how the size – in terms of electricity input (Pmax) and energy capacity (Emax......) – of the TES unit influences the savings. For this purpose, a reference price signal was used. Results show that it is possible to save up to approximately 14% of the electricity costs. In general, savings increase with Pmax and Emax. However, the benefit of increasing these two values ceases when certain...

  19. Optimal Operation of Electric Vehicles in Competitive Electricity Markets and Its Impact on Distribution Power Systems

    DEFF Research Database (Denmark)

    Hu, Weihao; Chen, Zhe; Bak-Jensen, Birgitte

    2011-01-01

    Since the hourly spot market price is available one day ahead in Denmark, the electricity price could be transferred to the consumers and they may make some optimal charge and discharge schedules for their electric vehicles in order to minimize their energy costs. This paper presents an optimal...... operation strategy for a Plug-In Electric Vehicle (PEV) in relation to the hourly electricity price in order to achieve minimum energy costs of the PEV. The western Danish power system, which is currently the grid area in the world that has the largest share of wind power in its generation profiles and may...... represent the future of electricity markets in some ways, is chosen as the studied power system in this paper. The impact of the optimal operation strategy for electric vehicles together with the optimal load response to spot market price on the distribution power system with high wind power penetrations...

  20. Community Energy: Analysis of Hydrogen Distributed Energy Systems with Photovoltaics for Load Leveling and Vehicle Refueling

    Energy Technology Data Exchange (ETDEWEB)

    Steward, D.; Zuboy, J.

    2014-10-01

    Energy storage could complement PV electricity generation at the community level. Because PV generation is intermittent, strategies must be implemented to integrate it into the electricity system. Hydrogen and fuel cell technologies offer possible PV integration strategies, including the community-level approaches analyzed in this report: (1) using hydrogen production, storage, and reconversion to electricity to level PV generation and grid loads (reconversion scenario); (2) using hydrogen production and storage to capture peak PV generation and refuel hydrogen fuel cell electric vehicles (FCEVs) (hydrogen fueling scenario); and (3) a comparison scenario using a battery system to store electricity for EV nighttime charging (electric charging scenario).