WorldWideScience

Sample records for energy control system

  1. Control of Solar Energy Systems

    CERN Document Server

    Camacho, Eduardo F; Rubio, Francisco R; Martínez, Diego

    2012-01-01

    Control of Solar Energy Systems details the main solar energy systems, problems involved with their control, and how control systems can help in increasing their efficiency.  After a brief introduction to the fundamental concepts associated with the use of solar energy in both photovoltaic and thermal plants, specific issues related to control of solar systems are embarked upon. Thermal energy systems are then explored in depth, as well as  other solar energy applications such as solar furnaces and solar refrigeration systems. Problems of variable generation profile and of the contribution of many solar plants to the same grid system are considered with the necessary integrated and supervisory control solutions being discussed. The text includes material on: ·         A comparison of basic and advanced control methods for parabolic troughs from PID to nonlinear model-based control; ·         solar towers and solar tracking; ·         heliostat calibration, characterization and off...

  2. Wind energy systems control engineering design

    CERN Document Server

    Garcia-Sanz, Mario

    2012-01-01

    IntroductionBroad Context and MotivationConcurrent Engineering: A Road Map for EnergyQuantitative Robust ControlNovel CAD Toolbox for QFT Controller DesignOutline Part I: Advanced Robust Control Techniques: QFT and Nonlinear SwitchingIntroduction to QFTQuantitative Feedback TheoryWhy Feedback? QFT OverviewInsight into the QFT TechniqueBenefits of QFTMISO Analog QFT Control SystemIntroductionQFT Method (Single-Loop MISO System)Design Procedure OutlineMinimum-Phase System Performance SpecificationsJ LTI Plant ModelsPlant Templates of P?(s), P( j_i )Nominal PlantU-Contour (Stability Bound)Trackin

  3. Synchronous generator wind energy conversion control system

    Energy Technology Data Exchange (ETDEWEB)

    Medeiros, A.L.R. [Wind Energy Group, Recife (Brazil); Lima, A.M.N.; Jacobina, C.B.; Simoes, F.J. [DEE, Campina Grande (Brazil)

    1996-12-31

    This paper presents the performance evaluation and the design of the control system of a WECS (Wind Energy Conversion System) that employs a synchronous generator based on its digital simulation. The WECS discussed in this paper is connected to the utility grid through two Pulse Width Modulated (PWM) power converters. The structure of the proposed WECS enables us to achieve high performance energy conversion by: (i) maximizing the wind energy capture and (ii) minimizing the reactive power flowing between the grid and the synchronous generator. 8 refs., 19 figs.

  4. Electron beam accelerator energy control system

    International Nuclear Information System (INIS)

    Sharma, Vijay; Rajan, Rehim; Acharya, S.; Mittal, K.C.

    2011-01-01

    A control system has been developed for the energy control of the electron beam accelerator using PLC. The accelerating voltage of 3 MV has been obtained by using parallel coupled voltage multiplier circuit. A autotransformer controlled variable 0-10 KV DC is fed to a tube based push pull oscillator to generate 120 Khz, 10 KV AC. Oscillator output voltage is stepped up to 0-300 KV/AC using a transformer. 0-300 KVAC is fed to the voltage multiplier column to generate the accelerating voltage at the dome 0-3 MV/DC. The control system has been designed to maintain the accelerator voltage same throughout the operation by adjusting the input voltage in close loop. Whenever there is any change in the output voltage either because of beam loading or arcing in the accelerator. The instantaneous accelerator voltage or energy is a direct proportional to 0-10 KVDC obtained from autotransformer. A PLC based control system with user settable energy level has been installed for 3 MeV, EB accelerator. The PLC takes the user defined energy value through a touch screen and compares it to the actual accelerating voltage (obtained using resistive divider). Depending upon the error the PLC generates the pulses to adjust the autotransformer to bring the actual voltage to the set value within the window of error (presently set to +/- 0.1%). (author)

  5. Control and automation, and energy system engineering

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Tai-hoon [Hannam Univ., Daejeon (Korea, Republic of); Adeli, Hojjat [Ohio State Univ., Columbus, OH (United States); Stoica, Adrian [Jet Propulsion Laboratory, Pasadena, CA (United States); Kang, Byeong-Ho (eds.) [Tasmania Univ., Hobart, TAS (Australia)

    2011-07-01

    This book comprises selected papers of the International Conferences, CA and CES3 2011, held as Part of the Future Generation Information Technology Conference, FGIT 2011, in Conjunction with GDC 2011, Jeju Island, Korea, in December 2011. The papers presented were carefully reviewed and selected from numerous submissions and focused on the various aspects of control and automation, and circuits, control, communication, electricity, electronics, energy, system, signal and simulation. (orig.)

  6. Adaptive control of solar energy collector systems

    CERN Document Server

    Lemos, João M; Igreja, José M

    2014-01-01

    This book describes methods for adaptive control of distributed-collector solar fields: plants that collect solar energy and deliver it in thermal form. Controller design methods are presented that can overcome difficulties found in these type of plants:they are distributed-parameter systems, i.e., systems with dynamics that depend on space as well as time;their dynamics is nonlinear, with a bilinear structure;there is a significant level of uncertainty in plant knowledge.Adaptive methods form the focus of the text because of the degree of uncertainty in the knowledge of plant dynamics. Parts

  7. Smart energy control systems for sustainable buildings

    CERN Document Server

    Spataru, Catalina; Howlett, Robert; Jain, Lakhmi

    2017-01-01

    There is widespread interest in the way that smart energy control systems, such as assessment and monitoring techniques for low carbon, nearly-zero energy and net positive buildings can contribute to a Sustainable future, for current and future generations. There is a turning point on the horizon for the supply of energy from finite resources such as natural gas and oil become less reliable in economic terms and extraction become more challenging, and more unacceptable socially, such as adverse public reaction to ‘fracking’. Thus, in 2016 these challenges are having a major influence on the design, optimisation, performance measurements, operation and preservation of: buildings, neighbourhoods, cities, regions, countries and continents. The source and nature of energy, the security of supply and the equity of distribution, the environmental impact of its supply and utilization, are all crucial matters to be addressed by suppliers, consumers, governments, industry, academia, and financial institutions. Thi...

  8. Energy Efficiency of Distributed Environmental Control Systems

    Energy Technology Data Exchange (ETDEWEB)

    Khalifa, H. Ezzat; Isik, Can; Dannenhoffer, John F. III

    2011-02-23

    In this report, we present an analytical evaluation of the potential of occupant-regulated distributed environmental control systems (DECS) to enhance individual occupant thermal comfort in an office building with no increase, and possibly even a decrease in annual energy consumption. To this end we developed and applied several analytical models that allowed us to optimize comfort and energy consumption in partitioned office buildings equipped with either conventional central HVAC systems or occupant-regulated DECS. Our approach involved the following interrelated components: 1. Development of a simplified lumped-parameter thermal circuit model to compute the annual energy consumption. This was necessitated by the need to perform tens of thousands of optimization calculations involving different US climatic regions, and different occupant thermal preferences of a population of ~50 office occupants. Yearly transient simulations using TRNSYS, a time-dependent building energy modeling program, were run to determine the robustness of the simplified approach against time-dependent simulations. The simplified model predicts yearly energy consumption within approximately 0.6% of an equivalent transient simulation. Simulations of building energy usage were run for a wide variety of climatic regions and control scenarios, including traditional “one-size-fits-all” (OSFA) control; providing a uniform temperature to the entire building, and occupant-selected “have-it-your-way” (HIYW) control with a thermostat at each workstation. The thermal model shows that, un-optimized, DECS would lead to an increase in building energy consumption between 3-16% compared to the conventional approach depending on the climate regional and personal preferences of building occupants. Variations in building shape had little impact in the relative energy usage. 2. Development of a gradient-based optimization method to minimize energy consumption of DECS while keeping each occupant

  9. Robust Control of Laddermill Wind Energy System

    NARCIS (Netherlands)

    Podgaets, A.R.; Ockels, W.J.

    2007-01-01

    Laddermill flight control problem with closed loop is considered in this paper. Laddermill is an alternative concept for energy production using high altitude kites. The kites have been simulated as rigid bodies and the cable as a thin elastic line. Euler angles and cable speed are controls. Flight

  10. Swinging control of two-pendulum system under energy constraints

    NARCIS (Netherlands)

    Ananyevskiy, M.S.; Fradkov, A.L.; Nijmeijer, H.; Leonov, G.; Nijmeijer, H.; Pogromsky, A.; Fradkov, A.

    2009-01-01

    A method for control of mechanical systems under phase constraints, applicable to energy control of Hamiltonian systems is proposed. The constrained energy control problem for two pendulums by a single control action is studied both analytically and numerically. It is shown that for a proper choice

  11. Geothermal energy control system and method

    Science.gov (United States)

    Matthews, Hugh B.

    1977-01-01

    A geothermal energy transfer and utilization system makes use of thermal energy stored in hot solute-bearing well water to generate super-heated steam from an injected flow of clean water; the super-heated steam is then used for operating a turbine-driven pump at the well bottom for pumping the hot solute-bearing water at high pressure and in liquid state to the earth's surface, where it is used by transfer of its heat to a closed-loop boiler-turbine-alternator combination for the generation of electrical or other power. Residual concentrated solute-bearing water is pumped back into the earth. The clean cooled water is regenerated at the surface-located system and is returned to the deep well pumping system also for lubrication of a novel bearing arrangement supporting the turbine-driven pump system. The bearing system employs liquid lubricated thrust and radial bearings with all bearing surfaces bathed in clean water serving as a lubricant and maintained under pressure to prevent entry into the bearings of contaminated geothermal fluid, an auxiliary thrust ball bearing arrangement comes into operation when starting or stopping the pumping system.

  12. Energy: Systems for Control, Maintenance, and Storage. A Bibliography.

    Science.gov (United States)

    Thomas, Gerald, Comp.; McKane, Irving, Comp.

    This publication is a bibliography of available periodical literature on specific aspects of energy and today's technology. The Applied Science and Technology Indexes were searched for articles that related to these specific areas: (1) Energy control systems; (2) Maintenance of Energy Systems; and (3) Energy storage. The articles and papers…

  13. Smart Cooling Controlled System Exploiting Photovoltaic Renewable Energy Systems

    Directory of Open Access Journals (Sweden)

    Ahmad Atieh

    2018-03-01

    Full Text Available A smart cooling system to control the ambient temperature of a premise in Amman, Jordan, is investigated and implemented. The premise holds 650 people and has 14 air conditioners with the cooling capacity ranging from 3 to 5 ton refrigerant (TR each. The control of the cooling system includes implementing different electronics circuits that are used to sense the ambient temperature and humidity, count the number of people in the premise and then turn ON/OFF certain air conditioner(s. The data collected by different electronic circuits are fed wirelessly to a microcontroller, which decides which air conditioner will be turned ON/OFF, its location and its desired set cooling temperature. The cooling system is integrated with an on-grid solar photovoltaic energy system to minimize the operational cost of the overall cooling system.

  14. Model Predictive Control for Smart Energy Systems

    DEFF Research Database (Denmark)

    Halvgaard, Rasmus

    pumps, heat tanks, electrical vehicle battery charging/discharging, wind farms, power plants). 2.Embed forecasting methodologies for the weather (e.g. temperature, solar radiation), the electricity consumption, and the electricity price in a predictive control system. 3.Develop optimization algorithms....... Chapter 3 introduces Model Predictive Control (MPC) including state estimation, filtering and prediction for linear models. Chapter 4 simulates the models from Chapter 2 with the certainty equivalent MPC from Chapter 3. An economic MPC minimizes the costs of consumption based on real electricity prices...... that determined the flexibility of the units. A predictive control system easily handles constraints, e.g. limitations in power consumption, and predicts the future behavior of a unit by integrating predictions of electricity prices, consumption, and weather variables. The simulations demonstrate the expected...

  15. Control Methods Utilizing Energy Optimizing Schemes in Refrigeration Systems

    DEFF Research Database (Denmark)

    Larsen, L.S; Thybo, C.; Stoustrup, Jakob

    2003-01-01

    The potential energy savings in refrigeration systems using energy optimal control has been proved to be substantial. This however requires an intelligent control that drives the refrigeration systems towards the energy optimal state. This paper proposes an approach for a control, which drives th...... the condenser pressure towards an optimal state. The objective of this is to present a feasible method that can be used for energy optimizing control. A simulation model of a simple refrigeration system will be used as basis for testing the control method....

  16. [Central nervous system control of energy homeostasis].

    Science.gov (United States)

    Machleidt, F; Lehnert, H

    2011-03-01

    The brain is continuously supplied with information about the distribution and amount of energy stores from the body periphery. Endocrine, autonomic and cognitive-hedonic signals are centrally integrated and exert effects on the whole organism via anabolic and catabolic pathways. The adiposity signals insulin and leptin reflect the amount of body fat and are part of a negative feedback mechanism between the periphery and the central nervous system. The hypothalamic arcuate nucleus is the most important central nervous structure, which integrates this information. Furthermore, the CNS is able to directly measure and to respond to changes in the concentration of certain nutrients. In order to develop effective therapies for the treatment of disorders of energy balance the further elucidation of these neuro-biological processes is of crucial importance. This article provides an overview of the CNS regulation of metabolism and its underlying molecular mechanisms. © Georg Thieme Verlag KG Stuttgart · New York.

  17. Qt based control system software for Low Energy Accelerator Facility

    International Nuclear Information System (INIS)

    Basu, A.; Singh, S.; Nagraju, S.B.V.; Gupta, S.; Singh, P.

    2012-01-01

    Qt based control system software for Low Energy Accelerating Facility (LEAF) is operational at Bhabha Atomic Research Centre (BARC), Trombay, Mumbai. LEAF is a 50 keV negative ion electrostatic accelerator based on SNICS ion source. Control system uses Nokia Trolltech's QT 4.x API for control system software. Ni 6008 USB based multifunction cards has been used for control and read back field equipments such as power supplies, pumps, valves etc. Control system architecture is designed to be client server. Qt is chosen for its excellent GUI capability and platform independent nature. Control system follows client server architecture. The paper will describe the control system. (author)

  18. Secure Control Systems for the Energy Sector

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Rhett [Schweitzer Engineering Lab., Inc., Alpharetta, GA (United States); Stewart, John [Tennessee Valley Authority, Knoxville, TN (United States); Chavez, Adrian [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2014-10-22

    The Padlock Project is an alliance between Tennessee Valley Authority (TVA), Sandia National Laboratories (SNL), and Schweitzer Engineering Laboratories Inc. (SEL). SEL is the prime contractor on the Padlock project. Rhett Smith (SEL) is the project director and Adrian Chaves (SNL) and John Stewart (TVA) are principle investigators. SEL is the world’s leader in microprocessor-based electronic equipment for protecting electric power systems. The Tennessee Valley Authority, a corporation owned by the U.S. government, provides electricity for 9 million people in parts of seven southeastern states at prices below the national average. TVA, which receives no taxpayer money and makes no profits, also provides flood control, navigation and land management for the Tennessee River system and assists utilities, and state and local governments with economic development.

  19. Software systems for energy control in the English industry

    International Nuclear Information System (INIS)

    Bouma, J.W.J.

    1993-01-01

    Monitoring and targeting software systems have proved to be valuable tools for energy control, permitting to save five to ten percent of energy. The article reviews the systems that are presently available in England and illustrates how these systems are successfully used in practice in small (British Telecom) and middle large (Charles Wells Brewery) industrial applications. (A.S.)

  20. Intelligent control of energy-saving power generation system

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Zhiyuan; Zhang, Guoqing; Guo, Zhizhong [Harbin Institute of Technology, Harbin (China). Dept. of Electrical Engineering

    2013-07-01

    Highway power generation system which is environmentally friendly and sustainable provides an innovative method of energy conversion. It is also as a kind of city science and technology innovation, which has the characteristics of environmental protection and sustainable utilization. Making full use of vehicle impact speed control humps, we design a new kind of highway speed control humps combined with solar electric generation system integration. Developing green energy, energy saving and environment protection can be achieved.

  1. Energy Efficient Engine: Control system preliminary definition report

    Science.gov (United States)

    Howe, David C.

    1986-01-01

    The object of the Control Preliminary Definition Program was to define a preliminary control system concept as a part of the Energy Efficient Engine program. The program was limited to a conceptual definition of a full authority digital electronic control system. System requirements were determined and a control system was conceptually defined to these requirements. Areas requiring technological development were identified and a plan was established for implementing the identified technological features, including a control technology demonstration. A significant element of this program was a study of the potential benefits of closed-loop active clearance control, along with laboratory tests of candidate clearance sensor elements for a closed loop system.

  2. Direct Energy Centre underground parking integrated light control system

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-10-15

    LightSavers is a project undertaken by the Toronto Atmospheric Fund to accelerate the use of lighting technologies. As part of the project a pilot test has been carried out in the Direct Energy Center in Toronto. The aim of this report is to present the study and its results. The Direct Energy Center is a large event facility with an large underground parking facility. A lighting energy management system, the energy control system (ECS), capable of adjusting lighting levels based on occupancy was implemented in the centre and data was collected during over one year. Results showed that the ECS permitted a reduction in energy consumption and thus greenhouse gas emissions by 47% and the payback will take less than 6 years. This project demonstrated that the energy control system provides better energy, environmental and economic performance than a traditional automation system.

  3. Energy Efficient Pump Control for an Offshore Oil Processing System

    DEFF Research Database (Denmark)

    Yang, Zhenyu; Soleiman, Kian; Løhndorf, Bo

    2012-01-01

    The energy efficient control of a pump system for an offshore oil processing system is investigated. The seawater is lifted up by a pump system which consists of three identical centrifugal pumps in parallel, and the lifted seawater is used to cool down the crude oil flowing out of a threephase...... separator on one of the Danish north-sea platform. A hierarchical pump-speed control strategy is developed for the considered system by minimizing the pump power consumption subject to keeping a satisfactory system performance. The proposed control strategy consists of online estimation of some system...... operating parameters, optimization of pump configurations, and a real-time feedback control. Comparing with the current control strategy at the considered system, where the pump system is on/off controlled, and the seawater flows are controlled by a number of control valves, the proposed control strategy...

  4. Fuzzy-Logic Subsumption Controller for Home Energy Management Systems

    Energy Technology Data Exchange (ETDEWEB)

    Ainsworth, Nathan; Johnson, Brian; Lundstrom, Blake

    2015-10-06

    Home Energy Management Systems (HEMS) are controllers that manage and coordinate the generation, storage, and loads in a home. These controllers are increasingly necessary to ensure that increasing penetrations of distributed energy resources are used effectively and do not disrupt the operation of the grid. In this paper, we propose a novel approach to HEMS design based on behavioral control methods, which do not require accurate models or predictions and are very responsive to changing conditions. We develop a proof-of-concept behavioral HEMS controller and show by simulation on an example home energy system that it capable of making context-dependent tradeoffs between goals under challenging conditions.

  5. A review of residential computer oriented energy control systems

    Energy Technology Data Exchange (ETDEWEB)

    North, Greg

    2000-07-01

    The purpose of this report is to bring together as much information on Residential Computer Oriented Energy Control Systems as possible within a single document. This report identifies the main elements of the system and is intended to provide many technical options for the design and implementation of various energy related services.

  6. Advanced Grid Control Technologies Workshop Series | Energy Systems

    Science.gov (United States)

    : Smart Grid and Beyond John McDonald, Director, Technical Strategy and Policy Development, General Control Technologies Workshop Series In July 2015, NREL's energy systems integration team hosted workshops the Energy Systems Integration Facility (ESIF) and included a technology showcase featuring projects

  7. Application of fuzzy control in cooling systems save energy design

    Energy Technology Data Exchange (ETDEWEB)

    Chen, M.L.; Liang, H.Y. [Chienkuo Technology Univ., Changhua, Taiwan (China). Dept. of Electrical Engineering

    2005-07-01

    A fuzzy logic programmable logic controller (PLC) was used to control the cooling systems of frigorific equipment. Frigorific equipment is used to move unwanted heat outside of building in order to control indoor temperatures. The aim of the fuzzy logic PLC was to improve the energy efficiency of the cooling system. Control of the cooling pump and cooling tower in the system was based on the water temperature of the condenser during frigorific system operation. A human computer design for the cooling system control was used to set speeds and to automate and adjust the motor according to the fuzzy logic controller. It was concluded that if fuzzy logic controllers are used with all components of frigorific equipment, energy efficiency will be significantly increased. 5 refs., 3 tabs., 9 figs.

  8. Energy-Based Controller Design of Stochastic Magnetic Levitation System

    Directory of Open Access Journals (Sweden)

    Weiwei Sun

    2017-01-01

    Full Text Available This paper investigates the control problem of magnetic levitation system, in which velocity feedback signal is influenced by stochastic disturbance. Firstly, single-degree-freedom magnetic levitation is regarded as an energy-transform action device. From the view of energy-balance relation, the magnetic levitation system is transformed into port-controlled Hamiltonian system model. Next, based on the Hamiltonian structure, the control law of magnetic levitation system is designed by applying Lyapunov theory. Finally, the simulation verifies the correctness of the proposed results.

  9. Gate controlled high efficiency ballistic energy conversion system

    NARCIS (Netherlands)

    Xie, Yanbo; Bos, Diederik; de Boer, Hans L.; van den Berg, Albert; Eijkel, Jan C.T.; Zengerle, R.

    2013-01-01

    Last year we demonstrated the microjet ballistic energy conversion system[1]. Here we show that the efficiency of such a system can be further improved by gate control. With gate control the electrical current generation is enhanced a hundred times with respect to the current generated from the zeta

  10. Feedback Linearization Controller for a Wind Energy Power System

    Directory of Open Access Journals (Sweden)

    Muthana Alrifai

    2016-09-01

    Full Text Available This paper deals with the control of a doubly-fed induction generator (DFIG-based variable speed wind turbine power system. A system of eight ordinary differential equations is used to model the wind energy conversion system. The generator has a wound rotor type with back-to-back three-phase power converter bridges between its rotor and the grid; it is modeled using the direct-quadrature rotating reference frame with aligned stator flux. An input-state feedback linearization controller is proposed for the wind energy power system. The controller guarantees that the states of the system track the desired states. Simulation results are presented to validate the proposed control scheme. Moreover, further simulation results are shown to investigate the robustness of the proposed control scheme to changes in some of the parameters of the system.

  11. Stochastic Model Predictive Control with Applications in Smart Energy Systems

    DEFF Research Database (Denmark)

    Sokoler, Leo Emil; Edlund, Kristian; Mølbak, Tommy

    2012-01-01

    to cover more than 50% of the total consumption by 2050. Energy systems based on significant amounts of renewable energy sources are subject to uncertainties. To accommodate the need for model predictive control (MPC) of such systems, the effect of the stochastic effects on the constraints must...... study, we consider a system consisting of fuel-fired thermal power plants, wind farms and electric vehicles....

  12. Electrical appliance energy consumption control methods and electrical energy consumption systems

    Science.gov (United States)

    Donnelly, Matthew K [Kennewick, WA; Chassin, David P [Pasco, WA; Dagle, Jeffery E [Richland, WA; Kintner-Meyer, Michael [Richland, WA; Winiarski, David W [Kennewick, WA; Pratt, Robert G [Kennewick, WA; Boberly-Bartis, Anne Marie [Alexandria, VA

    2006-03-07

    Electrical appliance energy consumption control methods and electrical energy consumption systems are described. In one aspect, an electrical appliance energy consumption control method includes providing an electrical appliance coupled with a power distribution system, receiving electrical energy within the appliance from the power distribution system, consuming the received electrical energy using a plurality of loads of the appliance, monitoring electrical energy of the power distribution system, and adjusting an amount of consumption of the received electrical energy via one of the loads of the appliance from an initial level of consumption to an other level of consumption different than the initial level of consumption responsive to the monitoring.

  13. Electrical appliance energy consumption control methods and electrical energy consumption systems

    Science.gov (United States)

    Donnelly, Matthew K [Kennewick, WA; Chassin, David P [Pasco, WA; Dagle, Jeffery E [Richland, WA; Kintner-Meyer, Michael [Richland, WA; Winiarski, David W [Kennewick, WA; Pratt, Robert G [Kennewick, WA; Boberly-Bartis, Anne Marie [Alexandria, VA

    2008-09-02

    Electrical appliance energy consumption control methods and electrical energy consumption systems are described. In one aspect, an electrical appliance energy consumption control method includes providing an electrical appliance coupled with a power distribution system, receiving electrical energy within the appliance from the power distribution system, consuming the received electrical energy using a plurality of loads of the appliance, monitoring electrical energy of the power distribution system, and adjusting an amount of consumption of the received electrical energy via one of the loads of the appliance from an initial level of consumption to an other level of consumption different than the initial level of consumption responsive to the monitoring.

  14. The energy consumption of control systems; Het energiegebruik van regelinstallaties

    Energy Technology Data Exchange (ETDEWEB)

    Van Gulik, A.R.; De Wildt, M.G. [Grontmij Nederland, Amersfoort (Netherlands)

    2013-07-15

    Control systems for e.g. indoor climate and illumination are essential in modern building services, and useful for comfort or energy conservation. Energy conservation is of course an important aim, but what is the energy consumption of the control systems? Is the consumption higher than the savings? This question was subject of a comprehensive study, with measurements and simulation calculations. It can be concluded that the energy consumption of control installation for spaces is substantial [Dutch] Regelinstallaties voor bijvoorbeeld klimaatregeling, verlichtingsregeling en domotica zijn niet meer weg te denken uit de moderne installatietechniek, of ze nu dienen voor comfort, gemak of energiebesparing. Maar hoeveel energie gebruiken deze installaties eigenlijk? Voor ontwerpers blijkt dit helemaal geen issue te zijn terwijl adviseurs, installateurs en zelfs fabrikanten zeggen hiervan geen idee te hebben. Door metingen en het gebruik van berekeningsmodellen is vastgesteld wat het energiegebruik van regelinstallaties op jaarbasis is. Dit blijkt substantieel te zijn, maar er zijn mogelijkheden om het gebruik te reduceren.

  15. Controlling chaotic and hyperchaotic systems via energy regulation

    International Nuclear Information System (INIS)

    Laval, L.; M'Sirdi, N.K.

    2003-01-01

    This paper focuses on a new control approach to steer trajectories of chaotic or hyperchaotic systems towards stable periodic orbits or stationary points of interest. This approach mainly consists in a variable structure control (VSC) that we extend by explicitly considering the system energy as basis for both controller design and system stabilization. In this paper, we present some theoretical results for a class of nonlinear (possibly chaotic or hyperchaotic) systems. Then some capabilities of the proposed approach are illustrated through examples related to a four-dimensional hyperchaotic system

  16. Power Converters and Control of Renewable Energy Systems

    DEFF Research Database (Denmark)

    Blaabjerg, Frede; Teodorescu, Remus; Chen, Zhe

    2004-01-01

    The global electrical energy consumption is steadily rising and therefore a continuous demand to increase the power generation capacity. A significant percentage of the required capacity increase can be based on renewable energy sources. Wind turbine technology, as the most cost effective renewable...... energy conversion system, will play an important part in our future energy supply. But other sources like microturbines, photovoltaics and fuel cell systems may also be serious contributor to the power supply. Characteristically, power electronics will be an efficient and important interface to the grid...... for the renewables and this paper will first briefly discuss three different alternative/renewable energy sources. Next, various configurations of small and medium power conversion topologies are presented including their control (mainly for PV-systems). Finally wind turbine configuration and their control...

  17. Hierarchical fuzzy control of low-energy building systems

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Zhen; Dexter, Arthur [Department of Engineering Science, University of Oxford, Parks Road, Oxford OX1 3PJ (United Kingdom)

    2010-04-15

    A hierarchical fuzzy supervisory controller is described that is capable of optimizing the operation of a low-energy building, which uses solar energy to heat and cool its interior spaces. The highest level fuzzy rules choose the most appropriate set of lower level rules according to the weather and occupancy information; the second level fuzzy rules determine an optimal energy profile and the overall modes of operation of the heating, ventilating and air-conditioning system (HVAC); the third level fuzzy rules select the mode of operation of specific equipment, and assign schedules to the local controllers so that the optimal energy profile can be achieved in the most efficient way. Computer simulation is used to compare the hierarchical fuzzy control scheme with a supervisory control scheme based on expert rules. The performance is evaluated by comparing the energy consumption and thermal comfort. (author)

  18. Controlled cooling of an electronic system for reduced energy consumption

    Science.gov (United States)

    David, Milnes P.; Iyengar, Madhusudan K.; Schmidt, Roger R.

    2016-08-09

    Energy efficient control of a cooling system cooling an electronic system is provided. The control includes automatically determining at least one adjusted control setting for at least one adjustable cooling component of a cooling system cooling the electronic system. The automatically determining is based, at least in part, on power being consumed by the cooling system and temperature of a heat sink to which heat extracted by the cooling system is rejected. The automatically determining operates to reduce power consumption of the cooling system and/or the electronic system while ensuring that at least one targeted temperature associated with the cooling system or the electronic system is within a desired range. The automatically determining may be based, at least in part, on one or more experimentally obtained models relating the targeted temperature and power consumption of the one or more adjustable cooling components of the cooling system.

  19. Controlled cooling of an electronic system for reduced energy consumption

    Energy Technology Data Exchange (ETDEWEB)

    David, Milnes P.; Iyengar, Madhusudan K.; Schmidt, Roger R.

    2018-01-30

    Energy efficient control of a cooling system cooling an electronic system is provided. The control includes automatically determining at least one adjusted control setting for at least one adjustable cooling component of a cooling system cooling the electronic system. The automatically determining is based, at least in part, on power being consumed by the cooling system and temperature of a heat sink to which heat extracted by the cooling system is rejected. The automatically determining operates to reduce power consumption of the cooling system and/or the electronic system while ensuring that at least one targeted temperature associated with the cooling system or the electronic system is within a desired range. The automatically determining may be based, at least in part, on one or more experimentally obtained models relating the targeted temperature and power consumption of the one or more adjustable cooling components of the cooling system.

  20. Hypothalamic control of energy metabolism via the autonomic nervous system

    NARCIS (Netherlands)

    Kalsbeek, A.; Bruinstroop, E.; Yi, C. X.; Klieverik, L. P.; La Fleur, S. E.; Fliers, E.

    2010-01-01

    The hypothalamic control of hepatic glucose production is an evident aspect of energy homeostasis. In addition to the control of glucose metabolism by the circadian timing system, the hypothalamus also serves as a key relay center for (humoral) feedback information from the periphery, with the

  1. Intelligent control with implementation on the wind energy conversion system

    International Nuclear Information System (INIS)

    Basma, Mohamad Khalil

    1997-05-01

    In this thesis our main job is to compare intelligent control and conventional control algorithms, by applying each scheme to the same control problem. Based on simulation, we analyze and compare the results of applying fuzzy logic and neural networks controllers on a popular control problem: variable speed wind energy conversion system. The reason behind our choice is the challenging nature of the problem where the plant should be controlled to maximize the power generated, while respecting its hardware constraints under varying operating conditions and disturbances. We have shown the effectiveness of fuzzy logic exciter controller for the adopted wind energy generator when compared to a conventional PI exciter. It showed better performance in the whole operating range. However, in the high wind speeds region, both controllers were unable to deliver the rpm requirements. We proposed the use of neural network intelligent techniques to supply us the optimal pitch. Our aim was to develop a simple and reliable controller that can deliver this optimal output, while remaining adaptive to system uncertainties and disturbances. The proposed fuzzy controller with a neural pitch controller showed best dynamic and robust performance as compared to the adaptive pitch controller together with the PI exciter. This study has shown that artificial neural networks and fuzzy logic control algorithms can be implemented for real time control implementations. the neuro-fuzzy control approach is robust and its performance is superior to that of traditional control methods. (author)

  2. Potential energy consumption reduction of automotive climate control systems

    International Nuclear Information System (INIS)

    Nielsen, Filip; Uddheim, Åsa; Dalenbäck, Jan-Olof

    2016-01-01

    Highlights: • Twenty-on energy saving measures for vehicle interior climate were evaluated. • Few single energy saving measures could reduce the energy use significantly. • The operation of the system in intermediate conditions determines the energy use. • Required heating/cooling of passenger compartment had small effect on energy use. - Abstract: In recent years fuel consumption of passenger vehicles has received increased attention by customers, the automotive industry, regulatory agencies and academia. One area which affect the fuel consumption is climate control systems. Twenty-one energy saving measures were evaluated regarding the total energy use for vehicle interior climate using simulation. Evaluated properties were heat flow into the passenger compartment, electrical and mechanical work. The simulation model included sub models of the passenger compartment, air-handling unit, Air Conditioning (AC) system, engine and engine cooling system. A real-world representative test cycle, which included tests in cold, intermediate and warm conditions, was used for evaluation. In general, few single energy saving measures could reduce the energy use significantly. The measures with most potential were increased blower efficiency with a reduction of 46% of the electrical work and increased AC-system disengage temperature with a reduction of 27% of the mechanical work. These results show that the operation of the climate control system had a large effect on the energy use, especially compared to the required heating and cooling of the passenger compartment. As a result energy saving measures need to address how heating and cooling is generated before reducing the heat flow into the passenger compartment.

  3. Automatic Energy Control And Monitoring System For Building

    Directory of Open Access Journals (Sweden)

    Hnin Nu Thaung

    2015-08-01

    Full Text Available The use of smart home technology in the home or building offers significant potential for energy savings. In this paper an energy management system based on wireless sensor networks. The proposed system is composed of two main components a wireless sensor network and monitoring terminal. Wireless sensors are used for sensing and transmitting electricity data and remote monitoring and control of appliances are provided to users through computer. The system enables users to save energy by monitoring and controlling appliances through terminal. This paper gives an overview of sensor technology and wireless networks in the development of an intelligent energy management system for buildings. This technology has ample potential to change the way live and work. ZigBee is used as a communication medium in building intelligent energy management system in this paper. From the prototype setup it is shown that ZigBee is a suitable technology to be adopted as the communication infrastructure in energy management system for buildings .The proposed system can be installed and maintained in residential environments with ease.

  4. Remote control systems evolution in the new open energy market

    International Nuclear Information System (INIS)

    Castiglioni, L.

    2001-01-01

    Considering new energy market in Italy, the new role of remote control applications is discussed. In the open market the whole electric process is managed by several different actors; common protocol scheme and additional sharing data policies are necessaries facing the increased communications requirements due to deregulation. Remote control systems evolution then will lead from process oriented to data management oriented systems; related methodologies and solutions are described [it

  5. Monitoring and control of a hybrid energy system

    International Nuclear Information System (INIS)

    Raceanu, M.; Culcer, M.; Patularu, L.; Enache, A.; Balan, M.; Varlam, M.

    2010-01-01

    Full text: This article presents monitoring and control of a Hybrid Energy System (HES). The HES is composed of six main components: solar panels, electrolyzer, fuel cells stack, charge controller, DC-AC inverter and lead acid batteries. Solar panels function as the primary source of energy, converting the energy from the sun into electricity that is given to a DC bus. Electrolyzer is a device that produces hydrogen and oxygen from the water following a process electrochemical. When there is excess energy from solar panels, electrolyzer is switched to produce hydrogen which is stored in hydrogen tank. Hydrogen produced is used by an assembly of fuel cell; this produces electricity that is transmitted on the DC bus, using hydrogen produced by electrolysis. Can be measured and displayed in real time data including, voltage, current, flow of hydrogen from the fuel cell, voltage, current, temperature of the photovoltaic panels, pressure hydrogen from electrolysis, pressure hydrogen tank and battery voltage. The control system is designed according to state of charge (SoC) of the battery. Are presented control strategy which ensures the On/Off control of the electrolyzer, to consume electricity from the battery and to generate electricity from fuel cells. The system hardware consists of an acquisition board, communication system of type CAN, sensors and interface devices. Monitoring and control software was developed in LabView 9.0. (authors)

  6. Compressed Air Energy Storage System Control and Performance Assessment Using Energy Harvested Index

    Directory of Open Access Journals (Sweden)

    Hanif SedighNejad

    2014-01-01

    Full Text Available In this paper a new concept for control and performance assessment of compressed air energy storage (CAES systems in a hybrid energy system is introduced. The proposed criterion, based on the concept of energy harvest index (HEI, measures the capability of a storage system to capture renewable energy. The overall efficiency of the CAES system and optimum control and design from the technical and economic point of view is presented. A possible application of this idea is an isolated community with significant wind energy resource. A case study reveals the usefulness of the proposed criterion in design, control and implementation of a small CAES system in a hybrid power system (HPM for an isolated community. Energy harvested index and its effectiveness in increasing the wind penetration rate in the total energy production is discussed.

  7. Adaptive control for solar energy based DC microgrid system development

    Science.gov (United States)

    Zhang, Qinhao

    During the upgrading of current electric power grid, it is expected to develop smarter, more robust and more reliable power systems integrated with distributed generations. To realize these objectives, traditional control techniques are no longer effective in either stabilizing systems or delivering optimal and robust performances. Therefore, development of advanced control methods has received increasing attention in power engineering. This work addresses two specific problems in the control of solar panel based microgrid systems. First, a new control scheme is proposed for the microgrid systems to achieve optimal energy conversion ratio in the solar panels. The control system can optimize the efficiency of the maximum power point tracking (MPPT) algorithm by implementing two layers of adaptive control. Such a hierarchical control architecture has greatly improved the system performance, which is validated through both mathematical analysis and computer simulation. Second, in the development of the microgrid transmission system, the issues related to the tele-communication delay and constant power load (CPL)'s negative incremental impedance are investigated. A reference model based method is proposed for pole and zero placements that address the challenges of the time delay and CPL in closed-loop control. The effectiveness of the proposed modeling and control design methods are demonstrated in a simulation testbed. Practical aspects of the proposed methods for general microgrid systems are also discussed.

  8. Control systems in the intersection of energy and ICT industries

    Energy Technology Data Exchange (ETDEWEB)

    Hellsten, K.; Kaessi, T.; Mustonen, T.; Paetaeri, S.; Soininen, L.

    2008-07-01

    The main objective of this research report is to shed light on business possibilities that are related to monitoring and control systems in the intersection of energy and ICT industries. The study uses both primary and secondary data sources that include a qualitative Delphi study, themed interviews, idea generation session, quantitative data regarding the alliances between the energy and ICT sectors as well as relevant literature. The environmental issues, the availability of energy, the opening energy markets, modern distributed generation and the saturation of existing transmission and distribution grids have raised a need to develop new energy solutions and business activities based on them. At the same time, the fast development in ICT technologies and automation has offered better possibilities for their implementation. Thus, the external factors and demands posed e.g. by political and social quarters as well as the internal needs of the energy companies make the cooperation in the intersection necessary and elaborate. The report reveals two major areas for the development of the cooperation between the energy and ICT sectors: households' energy utilization and distributed energy generation. In the former theme, e.g. the follow-up and guidance of energy consumption as well as new ways of electricity purchasing came up as issues for further examination. As regards to the second theme, the distributed energy solutions are seen to increase unavoidably and forcefully in the future. The emergence of distributed generation poses many new challenges for the whole energy system but also a vast amount of opportunities for the two sectors' co-operative activities, as the interfaces between the small local units and networks and the centralized system need to be controlled effectively and legitimately. (orig.)

  9. A Novel Coordinated Control of Renewable Energy Sources and Energy Storage System in Islanded Microgrid

    DEFF Research Database (Denmark)

    Gui, Yonghao; Li, Mingshen; Guerrero, Josep M.

    2018-01-01

    A novel coordinated control for energy storage system (ESS) and renewable energy source (RES) units is proposed in islanded AC microgrids without a phase-locked loop system. We use a proportional-resonant control technique for the ESS, which fixes the voltage and frequency of the microgrid...

  10. Hybrid photovoltaic system control for enhancing sustainable energy. Economic aspects

    International Nuclear Information System (INIS)

    Leva, Sonia; Roscia, Mariacristina; Zaninelli, Dario

    2005-01-01

    The paper introduces hybrid photovoltaic/diesel generation systems for supplying remote power plant taking into account the enhancement of sustainable energy on the economic point of view. In particular, a new monitoring and control device is presented in order to carry out the optimum energy flows and a cost evaluation is performed on a real plant showing the effect and weight of the economical sustainability and economical saving. (authors)

  11. On knowledge representation for high energy physics control systems

    International Nuclear Information System (INIS)

    Huuskonen, P.; Kaarela, K.; Meri, M.; Le Goff, J.M.

    1994-01-01

    A framework for knowledge representation in the domain of high energy physics control systems is presented. Models of process equipment, controls, documents, information systems, functional dependencies, physical interconnections, and design decisions are necessary to allow for automated reasoning about such systems. A number of support systems can use these models: alarm processing, fault diagnosis, sensor validation, preventive maintenance, action analysis, information abstraction, intelligent help systems, and on-line documentation. Our aim is to achieve representations that would be understood by end users, could be constructed by domain experts, and would be powerful enough to function as a basis for these support systems. It is proposed to base these models on means-end-analysis, implemented through an entity-relationship type of representation and extended with the notion of contribution. The paper outlines class hierarchies and relation types to form a vocabulary for talking about this specific domain. A number of implementation concerns are raised and some examples of how these representations can be used in real cases are offered. The representations are likely to prove most useful for support systems that function in the user assisting mode, as opposed to fully autonomous systems. Intelligent help and information abstraction applications, in particular, are expected to benefit. The main focus of the work is that of the control information system concepts based on encapsulated real- time objects (CICERO) project at CERN, experiment controls, but the results are usable for accelerator control systems and for industrial control systems in general. (author). 37 refs., 7 figs

  12. Optimal control of Formula One car energy recovery systems

    Science.gov (United States)

    Limebeer, D. J. N.; Perantoni, G.; Rao, A. V.

    2014-10-01

    The utility of orthogonal collocation methods in the solution of optimal control problems relating to Formula One racing is demonstrated. These methods can be used to optimise driver controls such as the steering, braking and throttle usage, and to optimise vehicle parameters such as the aerodynamic down force and mass distributions. Of particular interest is the optimal usage of energy recovery systems (ERSs). Contemporary kinetic energy recovery systems are studied and compared with future hybrid kinetic and thermal/heat ERSs known as ERS-K and ERS-H, respectively. It is demonstrated that these systems, when properly controlled, can produce contemporary lap time using approximately two-thirds of the fuel required by earlier generation (2013 and prior) vehicles.

  13. Modeling Smart Energy Systems for Model Predictive Control

    DEFF Research Database (Denmark)

    Halvgaard, Rasmus; Poulsen, Niels Kjølstad; Madsen, Henrik

    2012-01-01

    as it is produced requires a very exible and controllable power consumption. Examples of controllable electric loads are heat pumps in buildings and Electric Vehicles (EVs) that are expected to play a large role in the future danish energy system. These units in a smart energy system can potentially oer exibility...... on a time scale ranging from seconds to several days by moving power consumption, exploiting thermal inertia or battery storage capacity, respectively. Using advanced control algorithms these systems are able to reduce their own electricity costs by planning ahead and moving consumption to periods...... future price should also be available in order for the individual units to plan ahead in the most feasible way. This is necessary since Economic MPCs do not respond to the absolute cost of electricity, but to variations of the price over the prediction horizon. Economic MPC is ideal for price responsive...

  14. Energy Analysis for Air Conditioning System Using Fuzzy Logic Control

    Directory of Open Access Journals (Sweden)

    Henry Nasution

    2011-04-01

    Full Text Available Reducing energy consumption and to ensure thermal comfort are two important considerations for the designing an air conditioning system. An alternative approach to reduce energy consumption proposed in this study is to use a variable speed compressor. The control strategy will be proposed using the fuzzy logic controller (FLC. FLC was developed to imitate the performance of human expert operators by encoding their knowledge in the form of linguistic rules. The system is installed on a thermal environmental room with a data acquisition system to monitor the temperature of the room, coefficient of performance (COP, energy consumption and energy saving. The measurements taken during the two hour experimental periods at 5-minutes interval times for temperature setpoints of 20oC, 22oC and 24oC with internal heat loads 0, 500, 700 and 1000 W. The experimental results indicate that the proposed technique can save energy in comparison with On/Off and proportional-integral-derivative (PID control.

  15. Design and Control of Full Scale Wave Energy Simulator System

    DEFF Research Database (Denmark)

    Pedersen, Henrik C.; Hansen, Anders Hedegaard; Hansen, Rico Hjerm

    2012-01-01

    For wave energy to become feasible it is a requirement that the efficiency and reliability of the power take-off (PTO) systems are significantly improved. The cost of installing and testing PTO-systems at sea are however very high, and the focus of the current paper is therefore on the design...... of a full scale wave simulator for testing PTO-systems for point absorbers. The main challenge is here to design a system, which mimics the behavior of a wave when interacting with a given PTO-system. The paper includes a description of the developed system, located at Aalborg University......, and the considerations behind the design. Based on the description a model of the system is presented, which, along with a description of the wave theory applied, makes the foundation for the control strategy. The objective of the control strategy is to emulate not only the wave behavior, but also the dynamic wave...

  16. Trends in Energy Management Technology - Part 3: State of Practiceof Energy Management, Control, and Information Systems

    Energy Technology Data Exchange (ETDEWEB)

    Yee, Gaymond; Webster, Tom

    2004-02-01

    In this report, the third in a series, we provide an evaluation of several products that exemplify the current state of practice of Energy Management, Control, and Information Systems (EMCIS). The available features for these products are summarized and analyzed with regard to emerging trends in EMCIS and potential benefits to the federal sector. The first report [1] covered enabling technologies for emerging energy management systems. The second report [2] serves as a basic reference for building control system (BCS) networking fundamentals and includes an assessment of current approaches to open communications. Part 4 of this series will discuss applications software from a user's perspective. It is important for energy managers in the Federal sector to have a high level of knowledge and understanding of these complex energy management systems. This series of reports provides energy practitioners with some basic informational and educational tools to help make decisions relative to energy management systems design, specification, procurement, and energy savings potential.

  17. Energy Storage System Control Algorithm by Operating Target Power to Improve Energy Sustainability of Smart Home

    OpenAIRE

    Byeongkwan Kang; Kyuhee Jang; Sounghoan Park; Myeong-in Choi; Sehyun Park

    2018-01-01

    As energy issues are emerging around the world, a variety of smart home technologies aimed at realizing zero energy houses are being introduced. Energy storage system (ESS) for smart home energy independence is increasingly gaining interest. However, limitations exist in that most of them are controlled according to time schedules or used in conjunction with photovoltaic (PV) generation systems. In consideration of load usage patterns and PV generation of smart home, this study proposes an ES...

  18. Feedback control and adaptive control of the energy resource chaotic system

    International Nuclear Information System (INIS)

    Sun Mei; Tian Lixin; Jiang Shumin; Xu Jun

    2007-01-01

    In this paper, the problem of control for the energy resource chaotic system is considered. Two different method of control, feedback control (include linear feedback control, non-autonomous feedback control) and adaptive control methods are used to suppress chaos to unstable equilibrium or unstable periodic orbits. The Routh-Hurwitz criteria and Lyapunov direct method are used to study the conditions of the asymptotic stability of the steady states of the controlled system. The designed adaptive controller is robust with respect to certain class of disturbances in the energy resource chaotic system. Numerical simulations are presented to show these results

  19. Energy Management Control Systems: Tools for Energy Savings and Environmental Protection

    Science.gov (United States)

    Zsebik, Albin; Zala, Laszlo F.

    2002-01-01

    The change in the price of energy has encouraged the increase of energy efficiency. This report will discuss a tool to promote energy efficiency in intelligent buildings, energy management control systems (EMCS). In addition to the online control of energy production, supply, and consumption, the function of the EMCS is to support short- and long-term planning of the system operation as well as to collect, store, and regularly evaluate operation data. The strategies behind planning and implementing the EMCS as well as the manipulating the resulting data are discussed in this report.

  20. Model predictive control of wind energy conversion systems

    CERN Document Server

    Yaramasu, Venkata Narasimha R

    2017-01-01

    The authors provide a comprehensive analysis on the model predictive control of power converters employed in a wide variety of variable-speed wind energy conversion systems (WECS). The contents of this book includes an overview of wind energy system configurations, power converters for variable-speed WECS, digital control techniques, MPC, modeling of power converters and wind generators for MPC design. Other topics include the mapping of continuous-time models to discrete-time models by various exact, approximate, and quasi-exact discretization methods, modeling and control of wind turbine grid-side two-level and multilevel voltage source converters. The authors also focus on the MPC of several power converter configurations for full variable-speed permanent magnet synchronous generator based WECS, squirrel-cage induction generator based WECS, and semi-variable-speed doubly fed induction generator based WECS.

  1. Model Predictive Control for Distributed Microgrid Battery Energy Storage Systems

    DEFF Research Database (Denmark)

    Morstyn, Thomas; Hredzak, Branislav; Aguilera, Ricardo P.

    2018-01-01

    , and converter current constraints to be addressed. In addition, nonlinear variations in the charge and discharge efficiencies of lithium ion batteries are analyzed and included in the control strategy. Real-time digital simulations were carried out for an islanded microgrid based on the IEEE 13 bus prototypical......This brief proposes a new convex model predictive control (MPC) strategy for dynamic optimal power flow between battery energy storage (ES) systems distributed in an ac microgrid. The proposed control strategy uses a new problem formulation, based on a linear $d$ – $q$ reference frame voltage...... feeder, with distributed battery ES systems and intermittent photovoltaic generation. It is shown that the proposed control strategy approaches the performance of a strategy based on nonconvex optimization, while reducing the required computation time by a factor of 1000, making it suitable for a real...

  2. Control of Energy Storage Systems for Aeronautic Applications

    Directory of Open Access Journals (Sweden)

    G. Canciello

    2017-01-01

    Full Text Available Future aircraft will make more and more use of automated electric power system management onboard. Different solutions are currently being explored, and in particular the use of a supercapacitor as an intelligent energy storage device is addressed in this paper. The main task of the supercapacitor is to protect the electric generator from abrupt power changes resulting from sudden insertion or disconnection of loads or from loads with regenerative power capabilities, like electromagnetic actuators. A controller based on high-gain concepts is designed to drive a DC/DC converter connecting the supercapacitor to the main electric bus. Formal stability proofs are given for the resulting nonlinear system, and strong robustness results from the use of high-gain and variable structure control implementation. Moreover, detailed simulations including switching devices and electrical parasitic elements are provided for different working scenarios, showing the effectiveness of the proposed solution.

  3. Energy Storage System Control Algorithm by Operating Target Power to Improve Energy Sustainability of Smart Home

    Directory of Open Access Journals (Sweden)

    Byeongkwan Kang

    2018-01-01

    Full Text Available As energy issues are emerging around the world, a variety of smart home technologies aimed at realizing zero energy houses are being introduced. Energy storage system (ESS for smart home energy independence is increasingly gaining interest. However, limitations exist in that most of them are controlled according to time schedules or used in conjunction with photovoltaic (PV generation systems. In consideration of load usage patterns and PV generation of smart home, this study proposes an ESS control algorithm that uses constant energy of energy network while making maximum use of ESS. Constant energy means that the load consumes a certain amount of power under all conditions, which translates to low variability. The proposed algorithm makes a smart home a load of energy network with low uncertainty and complexity. The simulation results show that the optimal ESS operating target power not only makes the smart home use power constantly from the energy network, but also maximizes utilization of the ESS. In addition, since the smart home is a load that uses constant energy, it has the advantage of being able to operate an efficient energy network from the viewpoint of energy providers.

  4. Electro-mechanical energy conversion system having a permanent magnet machine with stator, resonant transfer link and energy converter controls

    Science.gov (United States)

    Skeist, S. Merrill; Baker, Richard H.

    2006-01-10

    An electro-mechanical energy conversion system coupled between an energy source and an energy load comprising an energy converter device including a permanent magnet induction machine coupled between the energy source and the energy load to convert the energy from the energy source and to transfer the converted energy to the energy load and an energy transfer multiplexer to control the flow of power or energy through the permanent magnetic induction machine.

  5. Economic Model Predictive Control for Smart Energy Systems

    DEFF Research Database (Denmark)

    Halvgaard, Rasmus

    Model Predictive Control (MPC) can be used to control the energy distribution in a Smart Grid with a high share of stochastic energy production from renewable energy sources like wind. Heat pumps for heating residential buildings can exploit the slow heat dynamics of a building to store heat and ...... and hereby shift the heat pump power consumption to periods with both low electricity prices and a high fraction of green energy in the grid.......Model Predictive Control (MPC) can be used to control the energy distribution in a Smart Grid with a high share of stochastic energy production from renewable energy sources like wind. Heat pumps for heating residential buildings can exploit the slow heat dynamics of a building to store heat...

  6. Improved Control Strategy for Microgrid Ultracapacitor Energy Storage Systems

    Directory of Open Access Journals (Sweden)

    Xiaobo Dou

    2014-12-01

    Full Text Available Ultracapacitors (UCs, with their features of high power density and high current charge-discharge, have become the best choice for dynamic power compensation to improve the stability of microgrids and are increasingly being applied in microgrids. This paper presents the control of an energy storage system (ESS based on ultracapacitors in the context of grid-connected microgrids. The ESS is composed of DC/AC and DC/DC converters tied by a dc link. An improved dynamic model for the ESS is proposed. Based on the proposed model a Proportional-Integral-Resonant (PIR DC link voltage controller is proposed to maintain the DC link voltage through the charging-discharging control of ultracapacitors, capable of working properly under all operating conditions. An extra double frequency component is injected into the UC current by a R controller to dynamically compensate for DC instantaneous power and double frequency AC instantaneous power due to unbalanced grid conditions and disturbances. This feature maintains the DC link voltage constant under unbalanced conditions and increases the degrees of freedom of the DC/AC converter and thus facilitates the application of UCs in microgrids. Simulation and experimental results verify the effectiveness of the proposed control strategy.

  7. Energy Systems Integration: Demonstrating Distribution Feeder Voltage Control

    Energy Technology Data Exchange (ETDEWEB)

    2017-01-01

    Overview fact sheet about the Smarter Grid Solutions Integrated Network Testbed for Energy Grid Research and Technology Experimentation (INTEGRATE) project at the Energy Systems Integration Facility. INTEGRATE is part of the U.S. Department of Energy's Grid Modernization Initiative.

  8. Energy Systems Integration: Demonstrating Distributed Grid-Edge Control Hierarchy

    Energy Technology Data Exchange (ETDEWEB)

    2017-01-01

    Overview fact sheet about the OMNETRIC Group Integrated Network Testbed for Energy Grid Research and Technology Experimentation (INTEGRATE) project at the Energy Systems Integration Facility. INTEGRATE is part of the U.S. Department of Energy's Grid Modernization Initiative.

  9. Expert system to control a fusion energy experiment

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, R.R.; Canales, T.; Lager, D.

    1986-01-01

    This paper describes a system that automates neutral beam source conditioning. The system achieves this with artificial intelligence techniques by encoding the behavior of several experts as a set of if-then rules in an expert system. One of the functions of the expert system is to control an adaptive controller that, in turn, controls the neutral beam source. The architecture of the system is presented followed by a description of its performance.

  10. Expert system to control a fusion energy experiment

    International Nuclear Information System (INIS)

    Johnson, R.R.; Canales, T.; Lager, D.

    1986-01-01

    This paper describes a system that automates neutral beam source conditioning. The system achieves this with artificial intelligence techniques by encoding the behavior of several experts as a set of if-then rules in an expert system. One of the functions of the expert system is to control an adaptive controller that, in turn, controls the neutral beam source. The architecture of the system is presented followed by a description of its performance

  11. Energy Optimal Tracking Control with Discrete Fluid Power Systems using Model Predictive Control

    DEFF Research Database (Denmark)

    Hansen, Anders Hedegaard; Asmussen, Magnus Færing; Bech, Michael Møller

    2017-01-01

    For Discrete Displacement Cylinder (DDC) drives the control task lies in choosing force level. Hence, which force level to apply and thereby which pressure level each cylinder chambers shall be connected to. The DDC system is inherently a force system why often a force reference is generated...... and compared to a PID like tracking controller combined with a FSA. The results indicate that the energy efficiency of position tracking DDC systems may be improved significantly by using the MPC algorithm....

  12. DSTATCOM with Flywheel Energy Storage System for wind energy applications: Control design and simulation

    Energy Technology Data Exchange (ETDEWEB)

    Suvire, G.O.; Mercado, P.E. [CONICET, Instituto de Energia Electrica, Universidad Nacional de San Juan, San Juan (Argentina)

    2010-03-15

    In this work, the use of a Distribution Static Synchronous Compensator (DSTATCOM) coupled with a Flywheel Energy Storage System (FESS) is proposed to mitigate problems introduced by wind generation in the electric system. A dynamic model of the DSTATCOM/FESS device is introduced and a multi-level control technique is proposed. This control technique presents one control mode for active power and two control modes for reactive power, power factor correction, and voltage control. Tests of dynamic response of the device are conducted, and performance characteristics are studied taking into consideration variations of power references. Moreover, the behaviour of the device is analyzed when combined with wind generation in the electric system. The results obtained demonstrate a good performance of the model developed and of the control technique proposed as well as a high effectiveness of the device to mitigate problems introduced by wind generation. (author)

  13. Stepless control system for reciprocating compressors: energy savings + process control improvement

    Energy Technology Data Exchange (ETDEWEB)

    Grande, Alvaro; Wenisch, Markus [Hoerbiger Ventilwerke GmbH and Co KG, Wien (Austria); Jacobs, Denis [HOERBIGER do Brasil Industria de Equipamentos, Cajamar, SP (Brazil)

    2012-07-01

    In the past, the capacity of reciprocating compressors was typically controlled by on/off unloaders (step-control) and recycle valves. But due to the fact that the power ratings of new reciprocating compressors for the oil and gas industry increase significantly, advanced control systems are required to reduce power costs and save energy. On top of that, multi-stage compressors are frequently integrated into complex process plants that demand precise control and operational flexibility. There are several solutions for this equation, but maybe the most successful is the use of the reverse flow principle applied to an electronically controlled and hydraulically actuated suction valve unloaders system. (author)

  14. Computer Controlled Portable Greenhouse Climate Control System for Enhanced Energy Efficiency

    Science.gov (United States)

    Datsenko, Anthony; Myer, Steve; Petties, Albert; Hustek, Ryan; Thompson, Mark

    2010-04-01

    This paper discusses a student project at Kettering University focusing on the design and construction of an energy efficient greenhouse climate control system. In order to maintain acceptable temperatures and stabilize temperature fluctuations in a portable plastic greenhouse economically, a computer controlled climate control system was developed to capture and store thermal energy incident on the structure during daylight periods and release the stored thermal energy during dark periods. The thermal storage mass for the greenhouse system consisted of a water filled base unit. The heat exchanger consisted of a system of PVC tubing. The control system used a programmable LabView computer interface to meet functional specifications that minimized temperature fluctuations and recorded data during operation. The greenhouse was a portable sized unit with a 5' x 5' footprint. Control input sensors were temperature, water level, and humidity sensors and output control devices were fan actuating relays and water fill solenoid valves. A Graphical User Interface was developed to monitor the system, set control parameters, and to provide programmable data recording times and intervals.

  15. Energy Storage System Control for Energy Management in Advanced Aeronautic Applications

    Directory of Open Access Journals (Sweden)

    A. Cavallo

    2017-01-01

    Full Text Available In this paper an issue related to electric energy management on board an aircraft is considered. A battery pack is connected to a high-voltage bus through a controlled Battery Charge/Discharge Unit (BCDU that makes the overall behaviour of the battery “intelligent.” Specifically, when the aeronautic generator feeding the high-voltage bus has enough energy the battery is kept under charge, while if more loads are connected to the bus, so that the overload capacity of the generator is exceeded, the battery “helps” the generator by releasing its stored energy. The core of the application is a robust, supervised control strategy for the BCDU that automatically reverts the flow of power in the battery, when needed. Robustness is guaranteed by a low-level high gain control strategy. Switching from full-charge mode (i.e., when the battery absorbs power from the generator to generator mode (i.e., when the battery pumps energy on the high-voltage bus is imposed by a high-level supervisor. Different from previous approaches, mathematical proofs of stability are given for the controlled system. A switching implementation using a finite-time convergent controller is also proposed. The effectiveness of the proposed strategy is shown by detailed simulations in Matlab/Stateflow/SimPowerSystem.

  16. Stochastic control applied to the ISWEC Wave Energy System

    International Nuclear Information System (INIS)

    Bracco, Giovanni; Casassa, Maria; Giorcelli, Ermanno; Mattiazzo, Giuliana; Passione, Biagio; Raffero, Mattia; Vissio, Giacomo; Martini, Michele

    2015-01-01

    ISWEC (Inertial Sea Wave Energy Converter) is a floating marine device able to harvest sea waves energy by the interaction between the pitching motion of a floater and a spinning flywheel which can drive an electric PTO. In the ISWEC the hull dynamics is governed and controlled by the gyroscopic torque. The optimal control logic results in tuning the floater dynamics to the incoming waves in order to maximize the power transfer from the waves to the floater. In this paper the control problems of the ISWEC are stated and a control scheme based on the sub-optimal stochastic control logic is presented. The control scheme here presented has been tested using real wave records acquired at the deployment location in Pantelleria Island, which is one of the most energetic sites of the Mediterranean Sea.

  17. Trends in Power Electronics and Control of Renewable Energy Systems

    DEFF Research Database (Denmark)

    Blaabjerg, Frede; Iov, Florin; Kerekes, Tamas

    2010-01-01

    term) based energy sources to renewable energy sources. Another is to use high efficient power electronics in power generation, power transmission/distribution and end-user application. This paper discuss trends of the most emerging renewable energy sources, wind energy and photovoltaics, which...... by means of power electronics are changing the future electrical infrastructure but also contributes steadily more to non-carbon based electricity production. Most focus is on the power electronics technologies used. In the case of photovoltaics transformer-less systems are discussed as they have...

  18. Fuzzy logic controller versus classical logic controller for residential hybrid solar-wind-storage energy system

    Energy Technology Data Exchange (ETDEWEB)

    Derrouazin, A., E-mail: derrsid@gmail.com [University Hassiba BenBouali of Chlef, LGEER,Chlef (Algeria); Université de Lorraine, LMOPS, EA 4423, 57070 Metz (France); CentraleSupélec, LMOPS, 57070 Metz (France); Aillerie, M., E-mail: aillerie@metz.supelec.fr; Charles, J. P. [Université de Lorraine, LMOPS, EA 4423, 57070 Metz (France); CentraleSupélec, LMOPS, 57070 Metz (France); Mekkakia-Maaza, N. [Université des sciences et de la Technologie d’Oran, Mohamed Boudiaf-USTO MB,LMSE, Oran Algérie (Algeria)

    2016-07-25

    Several researches for management of diverse hybrid energy systems and many techniques have been proposed for robustness, savings and environmental purpose. In this work we aim to make a comparative study between two supervision and control techniques: fuzzy and classic logics to manage the hybrid energy system applied for typical housing fed by solar and wind power, with rack of batteries for storage. The system is assisted by the electric grid during energy drop moments. A hydrogen production device is integrated into the system to retrieve surplus energy production from renewable sources for the household purposes, intending the maximum exploitation of these sources over years. The models have been achieved and generated signals for electronic switches command of proposed both techniques are presented and discussed in this paper.

  19. Fuzzy logic controller versus classical logic controller for residential hybrid solar-wind-storage energy system

    International Nuclear Information System (INIS)

    Derrouazin, A.; Aillerie, M.; Charles, J. P.; Mekkakia-Maaza, N.

    2016-01-01

    Several researches for management of diverse hybrid energy systems and many techniques have been proposed for robustness, savings and environmental purpose. In this work we aim to make a comparative study between two supervision and control techniques: fuzzy and classic logics to manage the hybrid energy system applied for typical housing fed by solar and wind power, with rack of batteries for storage. The system is assisted by the electric grid during energy drop moments. A hydrogen production device is integrated into the system to retrieve surplus energy production from renewable sources for the household purposes, intending the maximum exploitation of these sources over years. The models have been achieved and generated signals for electronic switches command of proposed both techniques are presented and discussed in this paper.

  20. Power Electronics Control of Wind Energy in Distributed Power System

    DEFF Research Database (Denmark)

    Iov, Florin; Ciobotaru, Mihai; Blaabjerg, Frede

    2008-01-01

    is to change the electrical power production sources from the conventional, fossil (and short term) based energy sources to renewable energy resources. The other is to use high efficient power electronics in power generation, power transmission/distribution and end-user application. This paper discuss the most...... emerging renewable energy sources, wind energy, which by means of power electronics are changing from being a minor energy source to be acting as an important power source in the energy system. Power electronics is the enabling technology and the presentation will cover the development in wind turbine...... technology from kW to MW, discuss which power electronic solutions are most feasible and used today....

  1. Investigation of energy management strategies for photovoltaic systems - A predictive control algorithm

    Science.gov (United States)

    Cull, R. C.; Eltimsahy, A. H.

    1983-01-01

    The present investigation is concerned with the formulation of energy management strategies for stand-alone photovoltaic (PV) systems, taking into account a basic control algorithm for a possible predictive, (and adaptive) controller. The control system controls the flow of energy in the system according to the amount of energy available, and predicts the appropriate control set-points based on the energy (insolation) available by using an appropriate system model. Aspects of adaptation to the conditions of the system are also considered. Attention is given to a statistical analysis technique, the analysis inputs, the analysis procedure, and details regarding the basic control algorithm.

  2. Adaptive control of energy storage systems for power smoothing applications

    DEFF Research Database (Denmark)

    Meng, Lexuan; Dragicevic, Tomislav; Guerrero, Josep M.

    2017-01-01

    Energy storage systems (ESSs) are desired and widely applied for power smoothing especially in systems with renewable generation and pulsed loads. High-pass-filter (HPF) is commonly applied in those applications in which the HPF extracts the high frequency fluctuating power and uses...... that as the power reference for ESS. The cut-off frequency, as the critical parameter, actually decides the power/energy compensated by ESS. Practically the state-of-charge (SoC) of the ESS has to be limited for safety and life-cycle considerations. In this paper an adaptive cut-off frequency design is proposed...

  3. Control Methods for Energy Management of Refrigeration Systems

    DEFF Research Database (Denmark)

    Shafiei, Seyed Ehsan

    is decreased as the method does not need an explicit model of the system and, at the same time, the desired load following performance is attained. Recent research findings indicate that the refrigeration system commonly employed in food transportation can account for 40% of the total greenhouse gas emissions...... from the corresponding vehicle engines. Finally, the problem of optimization of a hybrid transport refrigeration system is addressed here. The hybrid refrigeration system is made by the integration of conventional refrigeration technology with thermal energy storage devices....

  4. Intelligent Photovoltaic Maximum Power Point Tracking Controller for Energy Enhancement in Renewable Energy System

    Directory of Open Access Journals (Sweden)

    Subiyanto

    2013-01-01

    Full Text Available Photovoltaic (PV system is one of the promising renewable energy technologies. Although the energy conversion efficiency of the system is still low, but it has the advantage that the operating cost is free, very low maintenance and pollution-free. Maximum power point tracking (MPPT is a significant part of PV systems. This paper presents a novel intelligent MPPT controller for PV systems. For the MPPT algorithm, an optimized fuzzy logic controller (FLC using the Hopfield neural network is proposed. It utilizes an automatically tuned FLC membership function instead of the trial-and-error approach. The MPPT algorithm is implemented in a new variant of coupled inductor soft switching boost converter with high voltage gain to increase the converter output from the PV panel. The applied switching technique, which includes passive and active regenerative snubber circuits, reduces the insulated gate bipolar transistor switching losses. The proposed MPPT algorithm is implemented using the dSPACE DS1104 platform software on a DS1104 board controller. The prototype MPPT controller is tested using an agilent solar array simulator together with a 3 kW real PV panel. Experimental test results show that the proposed boost converter produces higher output voltages and gives better efficiency (90% than the conventional boost converter with an RCD snubber, which gives 81% efficiency. The prototype MPPT controller is also found to be capable of tracking power from the 3 kW PV array about 2.4 times more than that without using the MPPT controller.

  5. Energy Management of An Extended Hybrid Renewable Energy System For Isolated Sites Using A Fuzzy Logic Controller

    Science.gov (United States)

    Faquir, Sanaa; Yahyaouy, Ali; Tairi, Hamid; Sabor, Jalal

    2018-05-01

    This paper presents the implementation of a fuzzy logic controller to manage the flow of energy in an extended hybrid renewable energy system employed to satisfy the load for a wide isolated site at the city of Essaouira in Morocco. To achieve Efficient energy management, the system is combining two important renewable energies: solar and wind. Lithium Ion batteries were also used as storage devices to store the excess of energy provided by the renewable sources or to supply the system with the required energy when the energy delivered by the input sources is not enough to satisfy the load demand. To manage the energy in the system, a controller based on fuzzy logic was implemented. Real data taken from previous research and meteorological sites was used to test the controller.

  6. Improved beam jitter control methods for high energy laser systems

    OpenAIRE

    Frist, Duane C.

    2009-01-01

    Approved for public release, distribution unlimited The objective of this research was to develop beam jitter control methods for a High Energy Laser (HEL) testbed. The first step was to characterize the new HEL testbed at NPS. This included determination of natural frequencies and component models which were used to create a Matlab/Simulink model of the testbed. Adaptive filters using Filtered-X Least Mean Squares (FX-LMS) and Filtered-X Recursive Least Square (FX-RLS) were then implement...

  7. Solar-energy conversion system provides electrical power and thermal control for life-support systems

    Science.gov (United States)

    Davis, B. K.

    1974-01-01

    System utilizes Freon cycle and includes boiler turbogenerator with heat exchanger, regenerator and thermal-control heat exchangers, low-pressure and boiler-feed pumps, and condenser. Exchanger may be of interest to engineers and scientists investigating new energy sources.

  8. Energy-efficiency-oriented cascade control for vapor compression refrigeration cycle systems

    International Nuclear Information System (INIS)

    Yin, Xiaohong; Wang, Xinli; Li, Shaoyuan; Cai, Wenjian

    2016-01-01

    The vapor compression refrigeration cycle (VCC) system plays an important role and accounts for a large proportion of energy consumption from the heating, ventilating, and air-conditioning (HVAC) system. The traditional control approaches, for example PID control method, however, cannot meet the cooling demands with the satisfactory energy efficiency as well. This paper presents a novel energy-efficiency-oriented cascade control strategy for the VCC systems to improve the energy efficiency and fulfill the cooling requirements of indoor occupants simultaneously. In outer loop, a mathematic model is developed to determine the set point of superheat by a PI controller based on the nonlinear correlation between cooling demands and superheat degree. In inner loop, the pressure difference and superheat degree of evaporator are controlled by a model predictive control (MPC) strategy to track the values which are determined in the outer loop, simultaneously to enhance system efficiency of the VCC systems. Simulation and experiments studies are carried out to show the effectiveness of this proposed cascade control strategy and the results indicate significant tracking performance and energy efficiency improvements on VCC system. Compared to other schemes, the proposed cascade control strategy can improve energy efficiency by up to 5.8%. - Highlights: • Energy-efficiency-oriented cascade control strategy for VCC system is presented. • The correlation between cooling requirements and superheat is analyzed. • A MPC-based controller is developed to maximize system energy efficiency. • Experimental results confirm the effectiveness of the proposed control strategy.

  9. A Control Architecture to Coordinate Renewable Energy Sources and Energy Storage Systems in Islanded Microgrids

    DEFF Research Database (Denmark)

    Wu, Dan; Tang, Fen; Dragicevic, Tomislav

    2015-01-01

    Coordinated operation of microgrids requires that energy management system takes into account both the available power in renewable energy sources (RES) and storage capacity of energy storage systems (ESS). In this paper, a coordinated architecture of islanded AC microgrids with smooth switching...

  10. Energy evaluation of optimal control strategies for central VWV chiller systems

    International Nuclear Information System (INIS)

    Jin Xinqiao; Du Zhimin; Xiao Xiaokun

    2007-01-01

    Under various conditions, the actual load of the heating, ventilation and air conditioning (HVAC) systems is less than it is originally designed in most operation periods. To save energy and to optimize the controls for chilling systems, the performance of variable water volume (VWV) systems and characteristics of control systems are analyzed, and three strategies are presented and tested based on simulation in this paper. Energy evaluation for the three strategies shows that they can save energy to some extent, and there is potential remained. To minimize the energy consumption of chilling system, the setpoints of controls of supply chilled water temperature and supply head of secondary pump should be optimized simultaneously

  11. Control of hybrid fuel cell/energy storage distributed generation system against voltage sag

    Energy Technology Data Exchange (ETDEWEB)

    Hajizadeh, Amin; Golkar, Masoud Aliakbar [Electrical Engineering Department, K.N. Toosi University of Technology, Seyedkhandan, Dr. Shariati Ave, P.O. Box 16315-1355, Tehran (Iran)

    2010-06-15

    Fuel cell (FC) and energy storage (ES) based hybrid distributed power generation systems appear to be very promising for satisfying high energy and high power requirements of power quality problems in distributed generation (DG) systems. In this study, design of control strategy for hybrid fuel cell/energy storage distributed power generation system during voltage sag has been presented. The proposed control strategy allows hybrid distributed generation system works properly when a voltage disturbance occurs in distribution system and hybrid system stays connected to the main grid. Hence, modeling, controller design, and simulation study of a hybrid distributed generation system are investigated. The physical model of the fuel cell stack, energy storage and the models of power conditioning units are described. Then the control design methodology for each component of the hybrid system is proposed. Simulation results are given to show the overall system performance including active power control and voltage sag ride-through capability of the hybrid distributed generation system. (author)

  12. Data-driven modeling and real-time distributed control for energy efficient manufacturing systems

    International Nuclear Information System (INIS)

    Zou, Jing; Chang, Qing; Arinez, Jorge; Xiao, Guoxian

    2017-01-01

    As manufacturers face the challenges of increasing global competition and energy saving requirements, it is imperative to seek out opportunities to reduce energy waste and overall cost. In this paper, a novel data-driven stochastic manufacturing system modeling method is proposed to identify and predict energy saving opportunities and their impact on production. A real-time distributed feedback production control policy, which integrates the current and predicted system performance, is established to improve the overall profit and energy efficiency. A case study is presented to demonstrate the effectiveness of the proposed control policy. - Highlights: • A data-driven stochastic manufacturing system model is proposed. • Real-time system performance and energy saving opportunity identification method is developed. • Prediction method for future potential system performance and energy saving opportunity is developed. • A real-time distributed feedback control policy is established to improve energy efficiency and overall system profit.

  13. Industrial Control Systems/SCADA systems risk assessment in the energy sector

    Science.gov (United States)

    Falodun, Babatunde

    The energy sector is one of the most critical components of our national infrastructure. It not only provides the electrical power and petroleum required to run day-to-day operations and mechanisms in society, it's also an important element that directly impacts the economy with regard to growth and stability. Industrial Control Systems (ICS) /Supervisory Control and Data Acquisition Systems (SCADA) are computerized mechanisms, they are both software and hardware that are used to control real time processes and operations in power plants and oil production facilities. A significant attack on these control systems that leads to widespread disruption of energy could result in catastrophic consequences for any major city and even the nation. This research paper explores cyber threats and vulnerabilities faced by ICS/SCADA systems in the energy sector and also highlights possible outcomes of a successful breach. Furthermore, the research underscores mitigation strategies that could be used to prevent and respond to an attack. Keywords: Cybersecurity, SCADA, Cyber Attacks, Threats, Vulnerabilities, Risk Assessment, Dr. Albert Orbinati.

  14. Trends in Energy Management Technology - Part 4: Review ofAdvanced Applications in Energy Management, Control, and InformationSystems

    Energy Technology Data Exchange (ETDEWEB)

    Yee, Gaymond; Webster, Tom

    2003-08-01

    In this article, the fourth in a series, we provide a review of advanced applications in Energy Management, Control, and Information Systems (EMCIS). The available features for these products are summarized and analyzed with regard to emerging trends in EMCIS and potential benefits to the Federal sector. The first article [1] covered enabling technologies for emerging energy management systems. The second article [2] serves as a basic reference for building control system (BCS) networking fundamentals and includes an assessment of current approaches to open communications. The third article [3] evaluated several products that exemplify the current state of practice in EMCIS. It is important for energy managers in the Federal sector to have a high level of knowledge and understanding of these complex energy management systems. This series of articles provides energy practitioners with some basic informational and educational tools to help make decisions relative to energy management systems design, specification, procurement, and energy savings potential.

  15. Power electronics for renewable and distributed energy systems a sourcebook of topologies, control and integration

    CERN Document Server

    Chakraborty, Sudipta; Kramer, William E

    2013-01-01

    While most books approach power electronics and renewable energy as two separate subjects, Power Electronics for Renewable and Distributed Energy Systems takes an integrative approach; discussing power electronic converters topologies, controls and integration that are specific to the renewable and distributed energy system applications. An overview of power electronic technologies is followed by the introduction of various renewable and distributed energy resources that includes photovoltaics, wind, small hydroelectric, fuel cells, microturbines and variable speed generation. Energy storage s

  16. System state estimation and optimal energy control framework for multicell lithium-ion battery system

    International Nuclear Information System (INIS)

    Wei, Jingwen; Dong, Guangzhong; Chen, Zonghai; Kang, Yu

    2017-01-01

    Highlights: • Employed a dual-scale EKF based estimator for in-pack cells’ SOC values. • Proposed a two-stage hybrid state-feedback and output-feedback equalization algorithm. • A switchable balance current mode is designed in the equalization topology. • Verified the performance of proposed method under two conditions. - Abstract: Cell variations caused by the inevitable inconsistency during manufacture and use of battery cells have significant impacts on battery capacity, security and durability for battery energy storage systems. Thus, the battery equalization systems are essentially required to reduce variations of in-pack cells and increase battery pack capability. In order to protect all in-pack cells from damaging, estimate battery state and reduce variations, a system state estimation and energy optimal control framework for multicell lithium-ion battery system is proposed. The state-of-charge (SOC) values of all in-pack cells are firstly estimated using a dual-scale extended Kalman filtering (EKF) to improve estimation accuracy and reduce computation simultaneously. These estimated SOC values provide specific details of battery system, which cannot only be used to protect cells from over-charging/over-discharging, but also be employed to design state-feedback controller for battery equalization system. A two-stage hybrid state-feedback and output-feedback equalization algorithm is proposed. The state-feedback controller is firstly employed for coarse-grained adjustment to reduce equalization time cost with large current. However, due to the inevitable SOC estimation errors, the output-feedback controller is then used for fine-grained adjustment with trickle current. Experimental results show that the proposed framework can provide an effectively estimation and energy control for multicell battery systems. Finally, the implementation of the proposed method is further discussed for the real applications.

  17. Marine energy generation systems and related monitoring and control

    DEFF Research Database (Denmark)

    Blaabjerg, Frede; Liu, Hui; Loh, Poh Chiang

    2014-01-01

    Energy is very important to the world as a driver of the modern society. According to estimations done by the International Energy Agency (IEA), the total global energy consumption is about 17 500 TW·h/yr [1]. In the past, fossil fuels like coal, oil and natural gas supplied the biggest part...... of this global consumption, and they were far larger than those of the renewable energy sources as Fig. 1 shows for 1973 [2]. In 2011, the production of renewable energy and global energy consumption increased, even though renewable energy was still much smaller than fossil fuels as Fig. 1 shows. [2]....

  18. Multi-agent system-based event-triggered hybrid control scheme for energy internet

    DEFF Research Database (Denmark)

    Dou, Chunxia; Yue, Dong; Han, Qing Long

    2017-01-01

    This paper is concerned with an event-triggered hybrid control for the energy Internet based on a multi-agent system approach with which renewable energy resources can be fully utilized to meet load demand with high security and well dynamical quality. In the design of control, a multi-agent system...

  19. Energy-saving control strategy for lighting system based on multivariate extremum seeking with Newton algorithm

    International Nuclear Information System (INIS)

    Yin, Chun; Dadras, Sara; Huang, Xuegang; Mei, Jun; Malek, Hadi; Cheng, Yuhua

    2017-01-01

    Highlights: • An energy-saving control strategy is proposed for multi-group lighting sources. • The proposed controller is designed to minimize the light-energy consumption. • It is designed to speed up the convergence rate without increasing the oscillation. • The minimal energy usage is guaranteed, while keeping the desired lighting level. • Experimental results shows the superiorities of the energy-saving control strategy. - Abstract: In recent years, the energy problem has been a universal concern. In order to improve the lighting energy efficiency and reduce the electric energy consumption, this paper develops an energy-saving control strategy for the lighting system with multiple lighting sources. The control strategy presented in this paper includes two parts: a new multivariate extremum seeking control method with Newton algorithm is developed to minimize the light-energy consumption by separately manipulating the brightness of multiple lighting sources, and a proportion-integration-differentiation control approach is adopted to realize the desired lighting level. The proposed scheme can increase the convergence speed of the closed loop system toward the minimum light-energy consumption, meanwhile, the accuracy of the control strategy will be improved. Experimental results illustrate that the light-energy consumption via the proposed method can reach more rapidly to a smaller vicinity of the minimum energy point, so, the lighting energy efficiency is greatly increased accordingly.

  20. Fuzzy droop control loops adjustment for stored energy balance in distributed energy storage system

    DEFF Research Database (Denmark)

    Aldana, Nelson Leonardo Diaz; Wu, Dan; Dragicevic, Tomislav

    2015-01-01

    system, in order to smooth the variations at the prime energy generator. In this paper, a decentralized strategy based on fuzzy logic is proposed in order to balance the state of charge of distributed energy storage systems in lowvoltage three phase AC microgrid. The proposed method weights the action...

  1. Power Electronics and Control of Renewable Energy Systems

    DEFF Research Database (Denmark)

    Iov, Florin; Ciobotaru, Mihai; Sera, Dezso

    2007-01-01

    sources from the conventional, fossil (and short term) based energy sources to renewable energy resources. Another is to use high efficient power electronics in power generation, power transmission/distribution and end-user application. This paper discuss some of the most emerging renewable energy sources......The global electrical energy consumption is still rising and there is a demand to double the power capacity within 20 years. The production, distribution and use of energy should be as technological efficient as possible and incentives to save energy at the end-user should also be set up....... Deregulation of energy has in the past lowered the investment in larger power plants, which means the need for new electrical power sources may be very high in the near future. Two major technologies will play important roles to solve the future problems. One is to change the electrical power production...

  2. Energy consumption reduction in existing HVAC-R systems via a power law controlling kit

    International Nuclear Information System (INIS)

    Pinnola, C.F.; Vargas, J.V.C.; Buiar, C.L.; Ordonez, J.C.

    2015-01-01

    This paper presents an alternative solution for reducing energy consumption in heating, ventilation, air conditioning and refrigeration (HVAC-R) systems. For that, an existing typical commercial refrigeration system was equipped with a novel control system based on a power law, using a frequency inverter and a programmable logic controller (PLC). Hence, it was possible to compare the operation and energy consumption of the system with the power law control and with the on-off system, quantifying the obtained gains. The experimental unit consisted of a cooling chamber, an enclosing chamber (antechamber), and a vapor compression refrigeration system, i.e., an example of a practical commercial cooling system. A set of graphs shows the experimental measurements performed with the two systems. In this way, the measured temperatures in some selected points of the two systems, as well as the consumption in kWh for a period of 6 h and 10 min were compared in the tests. The main conclusions of this work are: i) The system operating with the power law control with respect to the conventional on-off control, showed energy consumption savings of up to 31% in a test period of 6 h and 10 min, and ii) The system compressor cycling frequency in the system operating with the power law control is smaller than with the traditional on-off system. Therefore, the study shows that the developed power law control kit has potential to be installed in any existing system with immediate significant energy savings with no need for HVAC-R hardware changes. - Highlights: • An energy consumption reduction strategy for HVAC-R systems is presented. • Power law and on-off control actions are experimentally compared. • Energy savings of 31% were obtained with power law control. • Compressor cycling frequency is smaller with power law control. • Power law control kit has potential to be installed in any existing system

  3. Control Systems for a Dynamic Multi-Physics Model of a Nuclear Hybrid Energy System

    Energy Technology Data Exchange (ETDEWEB)

    Greenwood, Michael Scott [ORNL; Fugate, David W [ORNL; Cetiner, Sacit M [ORNL

    2017-01-01

    A Nuclear Hybrid Energy System (NHES) uses a nuclear reactor as the basic power generation unit, and the power generated is used by multiple customers as either thermal power, electrical power, or both. The definition and architecture of a particular NHES can be adapted based on the needs and opportunities of different local markets. For example, locations in need of potable water may be best served by coupling a desalination plant to the NHES. Similarly, a location near oil refineries may have a need for emission-free hydrogen production. Using the flexible, multi-domain capabilities of Modelica, Argonne National Laboratory, Idaho National Laboratory, and Oak Ridge National Laboratory are investigating the dynamics (e.g., thermal hydraulics and electrical generation/consumption) and cost of a hybrid system. This paper examines the NHES work underway, emphasizing the control system developed for individual subsystems and the overall supervisory control system.

  4. Control of the DC-DC Converter used into Energy Generation System

    International Nuclear Information System (INIS)

    Bizon, Nicu; Oproescu, Mihai

    2006-01-01

    This paper presents an investigation of the DC-DC Converter controller used into Energy Generation System. The full bridge is used into an Energy Generation System (EGS) as second power interface between the energy source and the high DC bus. The simulation results show that the DC-DC Converter behavior can be improved using a well designed PI control surface. The used Simulink models for the EGS blocks and some design considerations are presented, too. (authors)

  5. Design a Smart Control Strategy to Implement an Intelligent Energy Safety and Management System

    OpenAIRE

    Jing-Min Wang; Ming-Ta Yang

    2014-01-01

    The energy saving and electricity safety are today a cause for increasing concern for homes and buildings. Integrating the radio frequency identification (RFID) and ZigBee wireless sensor network (WSN) mature technologies, the paper designs a smart control strategy to implement an intelligent energy safety and management system (IESMS) which performs energy measuring, controlling, monitoring, and saving of the power outlet system. The presented RFID and billing module is used to identify user...

  6. Systems and methods for controlling energy use in a building management system using energy budgets

    Science.gov (United States)

    Wenzel, Michael J.

    2012-06-17

    Systems and methods for limiting power consumption by a heating, ventilation, and air conditioning (HVAC) subsystem of a building are shown and described. A mathematical linear operator is found that transforms the unused or deferred cooling power usage of the HVAC system based on pre-determined temperature settings to a target cooling power usage. The mathematical operator is applied to the temperature settings to create a temperature setpoint trajectory expected to provide the target cooling power usage.

  7. The use of energy management and control systems to monitor the energy performance of commercial buildings

    Energy Technology Data Exchange (ETDEWEB)

    Heinemeier, Kristin Elizabeth [Univ. of California, Berkeley, CA (United States). Dept. of Architecture

    1994-12-01

    Monitored data play a very important part in the implementation and evaluation of energy conservation technologies and programs. However, these data can be expensive to collect, so there is a need for lower-cost alternatives. In many situations, using the computerized Energy Management and Control Systems (EMCSs)--already installed in many buildings--to collect these commercial building performance data has advantages over more conventional methods. This method provides data without installing incremental hardware, and the large amounts of available operational data can be a very rich resource for understanding building performance. This dissertation addresses several of these issues. One specific objective is to describe a monitoring-project planning process that includes definition of objectives, constraints, resources and approaches for the monitoring. The choice of tools is an important part of this process. The dissertation goes on to demonstrate, through eight case studies, that EMCS monitoring is possible, and to identify and categorize the problems and issues that can be encountered. These issues lead to the creation, use, and testing of a set of methods for evaluation of EMCS monitoring, in the form of guidelines. Finally, EMCS monitoring is demonstrated and compared with conventional monitoring more methodically in a detailed case study.

  8. Intelligent energy management control of vehicle air conditioning system coupled with engine

    International Nuclear Information System (INIS)

    Khayyam, Hamid; Abawajy, Jemal; Jazar, Reza N.

    2012-01-01

    Vehicle Air Conditioning (AC) systems consist of an engine powered compressor activated by an electrical clutch. The AC system imposes an extra load to the vehicle's engine increasing the vehicle fuel consumption and emissions. Energy management control of the vehicle air conditioning is a nonlinear dynamic system, influenced by uncertain disturbances. In addition, the vehicle energy management control system interacts with different complex systems, such as engine, air conditioning system, environment, and driver, to deliver fuel consumption improvements. In this paper, we describe the energy management control of vehicle AC system coupled with vehicle engine through an intelligent control design. The Intelligent Energy Management Control (IEMC) system presented in this paper includes an intelligent algorithm which uses five exterior units and three integrated fuzzy controllers to produce desirable internal temperature and air quality, improved fuel consumption, low emission, and smooth driving. The three fuzzy controllers include: (i) a fuzzy cruise controller to adapt vehicle cruise speed via prediction of the road ahead using a Look-Ahead system, (ii) a fuzzy air conditioning controller to produce desirable temperature and air quality inside vehicle cabin room via a road information system, and (iii) a fuzzy engine controller to generate the required engine torque to move the vehicle smoothly on the road. We optimised the integrated operation of the air conditioning and the engine under various driving patterns and performed three simulations. Results show that the proposed IEMC system developed based on Fuzzy Air Conditioning Controller with Look-Ahead (FAC-LA) method is a more efficient controller for vehicle air conditioning system than the previously developed Coordinated Energy Management Systems (CEMS). - Highlights: ► AC interacts: vehicle, environment, driver components, and the interrelationships between them. ► Intelligent AC algorithm which uses

  9. A current controlled matrix converter for wind energy conversion systems based on permanent magnet synchronous generator

    OpenAIRE

    Naggar H. Saad; Ahmed A. El-Sattar; Mohamed I. Marei

    2016-01-01

    The main challenges of wind energy conversion systems (WECS) are to maximize the energy capture from the wind and injecting reactive power during the fault. This paper presents a current controlled matrix converter to interface Permanent Magnet Synchronous Generators (PMSG) based WECS with the grid. To achieve fast dynamic response with reduced current ripples, a hysteresis current control is utilized. The proposed control system decouples the active and reactive components of the PMSG curren...

  10. The Control Based on Internal Average Kinetic Energy in Complex Environment for Multi-robot System

    Science.gov (United States)

    Yang, Mao; Tian, Yantao; Yin, Xianghua

    In this paper, reference trajectory is designed according to minimum energy consumed for multi-robot system, which nonlinear programming and cubic spline interpolation are adopted. The control strategy is composed of two levels, which lower-level is simple PD control and the upper-level is based on the internal average kinetic energy for multi-robot system in the complex environment with velocity damping. Simulation tests verify the effectiveness of this control strategy.

  11. Co-Simulation of Building Energy and Control Systems with the Building Controls Virtual Test Bed

    Energy Technology Data Exchange (ETDEWEB)

    Wetter, Michael

    2010-08-22

    This article describes the implementation of the Building Controls Virtual Test Bed (BCVTB). The BCVTB is a software environment that allows connecting different simulation programs to exchange data during the time integration, and that allows conducting hardware in the loop simulation. The software architecture is a modular design based on Ptolemy II, a software environment for design and analysis of heterogeneous systems. Ptolemy II provides a graphical model building environment, synchronizes the exchanged data and visualizes the system evolution during run-time. The BCVTB provides additions to Ptolemy II that allow the run-time coupling of different simulation programs for data exchange, including EnergyPlus, MATLAB, Simulink and the Modelica modelling and simulation environment Dymola. The additions also allow executing system commands, such as a script that executes a Radiance simulation. In this article, the software architecture is presented and the mathematical model used to implement the co-simulation is discussed. The simulation program interface that the BCVTB provides is explained. The article concludes by presenting applications in which different state of the art simulation programs are linked for run-time data exchange. This link allows the use of the simulation program that is best suited for the particular problem to model building heat transfer, HVAC system dynamics and control algorithms, and to compute a solution to the coupled problem using co-simulation.

  12. Economic Model Predictive Control for Large-Scale and Distributed Energy Systems

    DEFF Research Database (Denmark)

    Standardi, Laura

    Sources (RESs) in the smart grids is increasing. These energy sources bring uncertainty to the production due to their fluctuations. Hence,smart grids need suitable control systems that are able to continuously balance power production and consumption.  We apply the Economic Model Predictive Control (EMPC......) strategy to optimise the economic performances of the energy systems and to balance the power production and consumption. In the case of large-scale energy systems, the electrical grid connects a high number of power units. Because of this, the related control problem involves a high number of variables......In this thesis, we consider control strategies for large and distributed energy systems that are important for the implementation of smart grid technologies.  An electrical grid has to ensure reliability and avoid long-term interruptions in the power supply. Moreover, the share of Renewable Energy...

  13. Distributed Model Predictive Control for Smart Energy Systems

    DEFF Research Database (Denmark)

    Halvgaard, Rasmus Fogtmann; Vandenberghe, Lieven; Poulsen, Niels Kjølstad

    2016-01-01

    Integration of a large number of flexible consumers in a smart grid requires a scalable power balancing strategy. We formulate the control problem as an optimization problem to be solved repeatedly by the aggregator in a model predictive control framework. To solve the large-scale control problem...

  14. Enhanced Reliability of Photovoltaic Systems with Energy Storage and Controls

    Energy Technology Data Exchange (ETDEWEB)

    Manz, D.; Schelenz, O.; Chandra, R.; Bose, S.; de Rooij, M.; Bebic, J.

    2008-02-01

    This report summarizes efforts to reconfigure loads during outages to allow individual customers the opportunity to enhance the reliability of their electric service through the management of their loads, photovoltaics, and energy storage devices.

  15. Fuzzy Logic based Coordinated Control of Battery Energy Storage System and Dispatchable Distributed Generation for Microgrid

    DEFF Research Database (Denmark)

    Zhao, Haoran; Wu, Qiuwei; Wang, Chengshan

    2015-01-01

    Microgrid is an efficient solution to integraterenewable energy sources (RES) into power systems. Inorder to deal with the intermittent characteristics of therenewable energy based distributed generation (DG) units,a fuzzy-logic based coordinated control strategy of thebattery energy storage system...... (BESS) and dispatchableDG units is proposed in this paper for the microgridmanagement system (MMS). In the proposed coordinatedcontrol strategy, the BESS is used to mitigate the activepower exchange at the point of common coupling of themicrogrid for the grid-connected operation, and is used forthe...... frequency control for the island operation. Theeffectiveness of the proposed control strategy was verifiedby case studies using DIgSILENT/PowerFactroy....

  16. Calibrating a combined energy systems analysis and controller design method with empirical data

    International Nuclear Information System (INIS)

    Murphy, Gavin Bruce; Counsell, John; Allison, John; Brindley, Joseph

    2013-01-01

    The drive towards low carbon constructions has seen buildings increasingly utilise many different energy systems simultaneously to control the human comfort of the indoor environment; such as ventilation with heat recovery, various heating solutions and applications of renewable energy. This paper describes a dynamic modelling and simulation method (IDEAS – Inverse Dynamics based Energy Assessment and Simulation) for analysing the energy utilisation of a building and its complex servicing systems. The IDEAS case study presented in this paper is based upon small perturbation theory and can be used for the analysis of the performance of complex energy systems and also for the design of smart control systems. This paper presents a process of how any dynamic model can be calibrated against a more empirical based data model, in this case the UK Government's SAP (Standard Assessment Procedure). The research targets of this work are building simulation experts for analysing the energy use of a building and also control engineers to assist in the design of smart control systems for dwellings. The calibration process presented is transferable and has applications for simulation experts to assist in calibrating any dynamic building simulation method with an empirical based method. - Highlights: • Presentation of an energy systems analysis method for assessing the energy utilisation of buildings and their complex servicing systems. • An inverse dynamics based controller design method is detailed. • Method of how a dynamic model can be calibrated with an empirical based model

  17. Robust multi-objective control of hybrid renewable microgeneration systems with energy storage

    International Nuclear Information System (INIS)

    Allison, John

    2017-01-01

    Highlights: • A hybrid energy system of micro-CHP, solar PV, and battery storage is presented. • Possible to exploit synergy of systems to fulfil the thermal and electrical demands. • Can control to minimise the interaction with the local electrical network. • Three different control approaches were compared. • The nonlinear inversion-based control strategy exhibits optimum performance. - Abstract: Microgeneration technologies are positioned to address future building energy efficiency requirements and facilitate the integration of renewables into buildings to ensure a sustainable, energy-secure future. This paper explores the development of a robust multi-input multi-output (MIMO) controller applicable to the control of hybrid renewable microgeneration systems with the objective of minimising the electrical grid utilisation of a building while fulfilling the thermal demands. The controller employs the inverse dynamics of the building, servicing systems, and energy storage with a robust control methodology. These inverse dynamics provides the control system with knowledge of the complex cause and effect relationships between the system, the controlled inputs, and the external disturbances, while an outer-loop control ensures robust, stable control in the presence of modelling deficiencies/uncertainty and unknown disturbances. Variable structure control compensates for the physical limitations of the systems whereby the control strategy employed switches depending on the current utilisation and availability of the energy supplies. Preliminary results presented for a system consisting of a micro-CHP unit, solar PV, and battery storage indicate that the control strategy is effective in minimising the interaction with the local electrical network and maximising the utilisation of the available renewable energy.

  18. Modeling and Nonlinear Control of Fuel Cell / Supercapacitor Hybrid Energy Storage System for Electric Vehicles

    DEFF Research Database (Denmark)

    El Fadil, Hassan; Giri, Fouad; Guerrero, Josep M.

    2014-01-01

    This paper deals with the problem of controlling hybrid energy storage system (HESS) for electric vehicle. The storage system consists of a fuel cell (FC), serving as the main power source, and a supercapacitor (SC), serving as an auxiliary power source. It also contains a power block for energy...

  19. Lyapunov based control of hybrid energy storage system in electric vehicles

    DEFF Research Database (Denmark)

    El Fadil, H.; Giri, F.; Guerrero, Josep M.

    2012-01-01

    This paper deals with a Lyapunov based control principle in a hybrid energy storage system for electric vehicle. The storage system consists on fuel cell (FC) as a main power source and a supercapacitor (SC) as an auxiliary power source. The power stage of energy conversion consists on a boost...

  20. Dynamic target high pressure control of a VRF system for heating energy savings

    International Nuclear Information System (INIS)

    Yun, Geun Young; Lee, Je Hyeon; Kim, Inhan

    2017-01-01

    Highlights: • We developed the dynamic target high pressure control of a VRF system. • We created the VRF control model using the EnergyPlus runtime language. • Multicalorimeter experimental results indicate that the energy efficiency improved by 21%. • EnergyPlus simulations demonstrate that the annual heating energy consumption was lowered by 22%. - Abstract: Variable refrigerant flow (VRF) systems are widely used because of their ability to provide individualized comfort control with energy-saving potential. This study develops load responsive high pressure control of a VRF system with the aim of reducing the heating energy consumption of a VRF system under part load conditions. The developed control consists of two parts: one part that determines the level of heating load, and the other that assigns a target high pressure based on the level of heating load. In this way, the compressor speed can be accurately matched to heating load, which improves the energy performance of the VRF system. A series of multicalorimeter experiments revealed that the heating capacity of the VRF system varied by 45% by modulating the target high pressure and that its efficiency was enhanced by 21% by changing the high pressure from 30 kgf/cm"2 to 25 kgf/cm"2. To evaluate the annual heating energy performance of the VRF system with the developed control, a custom computer code was developed to implement the developed control using a programming language called EnergyPlus Runtime Language. Simulation outcomes showed that the annual heating energy consumption of a medium-size office building was reduced by 22% when the developed control was applied.

  1. Experimental analysis of fuzzy controlled energy efficient demand controlled ventilation economizer cycle variable air volume air conditioning system

    Directory of Open Access Journals (Sweden)

    Rajagopalan Parameshwaran

    2008-01-01

    Full Text Available In the quest for energy conservative building design, there is now a great opportunity for a flexible and sophisticated air conditioning system capable of addressing better thermal comfort, indoor air quality, and energy efficiency, that are strongly desired. The variable refrigerant volume air conditioning system provides considerable energy savings, cost effectiveness and reduced space requirements. Applications of intelligent control like fuzzy logic controller, especially adapted to variable air volume air conditioning systems, have drawn more interest in recent years than classical control systems. An experimental analysis was performed to investigate the inherent operational characteristics of the combined variable refrigerant volume and variable air volume air conditioning systems under fixed ventilation, demand controlled ventilation, and combined demand controlled ventilation and economizer cycle techniques for two seasonal conditions. The test results of the variable refrigerant volume and variable air volume air conditioning system for each techniques are presented. The test results infer that the system controlled by fuzzy logic methodology and operated under the CO2 based mechanical ventilation scheme, effectively yields 37% and 56% per day of average energy-saving in summer and winter conditions, respectively. Based on the experimental results, the fuzzy based combined system can be considered to be an alternative energy efficient air conditioning scheme, having significant energy-saving potential compared to the conventional constant air volume air conditioning system.

  2. Towards energy efficient operation of Heating, Ventilation and Air Conditioning systems via advanced supervisory control design

    Science.gov (United States)

    Oswiecinska, A.; Hibbs, J.; Zajic, I.; Burnham, K. J.

    2015-11-01

    This paper presents conceptual control solution for reliable and energy efficient operation of heating, ventilation and air conditioning (HVAC) systems used in large volume building applications, e.g. warehouse facilities or exhibition centres. Advanced two-level scalable control solution, designed to extend capabilities of the existing low-level control strategies via remote internet connection, is presented. The high-level, supervisory controller is based on Model Predictive Control (MPC) architecture, which is the state-of-the-art for indoor climate control systems. The innovative approach benefits from using passive heating and cooling control strategies for reducing the HVAC system operational costs, while ensuring that required environmental conditions are met.

  3. Computer-controlled system for plasma ion energy auto-analyzer

    International Nuclear Information System (INIS)

    Wu Xianqiu; Chen Junfang; Jiang Zhenmei; Zhong Qinghua; Xiong Yuying; Wu Kaihua

    2003-01-01

    A computer-controlled system for plasma ion energy auto-analyzer was technically studied for rapid and online measurement of plasma ion energy distribution. The system intelligently controls all the equipments via a RS-232 port, a printer port and a home-built circuit. The software designed by LabVIEW G language automatically fulfils all of the tasks such as system initializing, adjustment of scanning-voltage, measurement of weak-current, data processing, graphic export, etc. By using the system, a few minutes are taken to acquire the whole ion energy distribution, which rapidly provide important parameters of plasma process techniques based on semiconductor devices and microelectronics

  4. Comparison of Sliding Mode Control and Fuzzy Logic control applied to Variable Speed Wind Energy Conversion Systems

    Directory of Open Access Journals (Sweden)

    Souhila Rached Zine

    2015-08-01

    Full Text Available wind energy features prominently as a supplementary energy booster. It does not pollute and is inexhaustible. However, its high cost is a major constraint, especially on the less windy sites. The purpose of wind energy systems is to maximize energy efficiency, and extract maximum power from the wind speed. In This case, the MPPT control becomes important. To realize this control, strategy conventional Proportional and Integral (PI controller is usually used. However, this strategy cannot achieve better performance. This paper proposes other control methods of a turbine which optimizes its production such as fuzzy logic, sliding mode control. These methods improve the quality and energy efficiency. The proposed Sliding Mode Control (SMC strategy and the fuzzy controllers have presented attractive features such as robustness to parametric uncertainties of the turbine, simplicity of its design and good performances. The simulation result under Matlab\\Simulink has validated the performance of the proposed MPPT strategies.

  5. Sustainable Energy Solutions Task 1.0: Networked Monitoring and Control of Small Interconnected Wind Energy Systems

    Energy Technology Data Exchange (ETDEWEB)

    edu, Janet. twomey@wichita. [Wichita State Univ., KS (United States)

    2010-04-30

    This report presents accomplishments, results, and future work for one task of five in the Wichita State University Sustainable Energy Solutions Project: To develop a scale model laboratory distribution system for research into questions that arise from networked control and monitoring of low-wind energy systems connected to the AC distribution system. The lab models developed under this task are located in the Electric Power Quality Lab in the Engineering Research Building on the Wichita State University campus. The lab system consists of four parts: 1. A doubly-fed induction generator 2. A wind turbine emulator 3. A solar photovoltaic emulator, with battery energy storage 4. Distribution transformers, lines, and other components, and wireless and wired communications and control These lab elements will be interconnected and will function together to form a complete testbed for distributed resource monitoring and control strategies and smart grid applications testing. Development of the lab system will continue beyond this project.

  6. Information Support of Optimal Control of Modes of Electric Systems with Renewable Energy Sources

    Directory of Open Access Journals (Sweden)

    Michalina Gryniewicz-Jaworska

    2017-12-01

    Full Text Available To provide necessary quality of electric energy and reliable supply and reduce environmental contamination as a result of energy units operation, renewable sources of energy (RSE, in particular solar electric stations (SES, wind electric stations (WES and small hydropower stations (SHES are intensively developed. The paper considers the conditions of optimality of renewable sources of energy (RSE functioning in electric systems, controllability of which is limited by the impact of non-stable weather conditions. The influence of control system information support on the efficiency of RSE usage is shown.

  7. Challenges of implementing economic model predictive control strategy for buildings interacting with smart energy systems

    DEFF Research Database (Denmark)

    Zong, Yi; Böning, Georg Martin; Santos, Rui Mirra

    2016-01-01

    ) strategy for energy management in smart buildings, which can act as active users interacting with smart energy systems. The challenges encountered during the implementation of EMPC for active demand side management are investigated in detail in this paper. A pilot testing study shows energy savings......When there is a high penetration of renewables in the energy system, it requires proactive control of large numbers of distributed demand response resources to maintain the system’s reliability and improve its operational economics. This paper presents the Economic Model Predictive Control (EMPC...

  8. DC Distributed Power Systems. Analysis, Design and Control for a Renewable Energy System

    Energy Technology Data Exchange (ETDEWEB)

    Karlsson, Per

    2002-12-01

    Renewable energy systems are likely to become wide spread in the future due to environmental demands. As a consequence of the dispersed nature of renewable energy systems, this implies that there will be a distributed generation of electric power. Since most of the distributed electrical energy sources do not provide their electric power at line frequency and voltage, a DC bus is a useful common connection for several such sources. Due to the differences in output voltage among the sources, depending on both the type of source and their actual operating point, the sources are connected to the DC power system via power electronic converters. The intention behind the presented work is not to replace the existing AC power system, but to include local DC power systems. The AC and DC power systems are connected at some points in the network. The renewable energy sources are weak compared to the present hydro power and nuclear power plants, resulting in a need of power conditioning before the renewable energy is fed to the transmission lines. The benefit of such an approach is that power conditioning is applied on a central level, i.e. at the interface between the AC and DC power systems. The thesis starts with an overview of related work. Present DC transmission systems are discussed and investigated in simulations. Then, different methods for load sharing and voltage control are discussed. Especially, the voltage droop control scheme is examined thoroughly. Since the droop control method does not require any high-speed communication between sources and loads, this is considered the most suitable for DC distributed power systems. The voltage feed back design of the controller also results in a specification of the DC bus capacitors (equivalents to DC link capacitors of single converters) needed for filtering. If the converters in the DC distribution system are equipped with capacitors selected from this design criterion and if the DC bus impedance is neglected, the

  9. Genetic algorithm-based fuzzy-PID control methodologies for enhancement of energy efficiency of a dynamic energy system

    International Nuclear Information System (INIS)

    Jahedi, G.; Ardehali, M.M.

    2011-01-01

    The simplicity in coding the heuristic judgment of experienced operator by means of fuzzy logic can be exploited for enhancement of energy efficiency. Fuzzy logic has been used as an effective tool for scheduling conventional PID controllers gain coefficients (F-PID). However, to search for the most desirable fuzzy system characteristics that allow for best performance of the energy system with minimum energy input, optimization techniques such as genetic algorithm (GA) could be utilized and the control methodology is identified as GA-based F-PID (GA-F-PID). The objective of this study is to examine the performance of PID, F-PID, and GA-F-PID controllers for enhancement of energy efficiency of a dynamic energy system. The performance evaluation of the controllers is accomplished by means of two cost functions that are based on the quadratic forms of the energy input and deviation from a setpoint temperature, referred to as energy and comfort costs, respectively. The GA-F-PID controller is examined in two different forms, namely, global form and local form. For the global form, all possible combinations of fuzzy system characteristics in the search domain are explored by GA for finding the fittest chromosome for all discrete time intervals during the entire operation period. For the local form, however, GA is used in each discrete time interval to find the fittest chromosome for implementation. The results show that the global form GA-F-PID and local form GA-F-PID control methodologies, in comparison with PID controller, achieve higher energy efficiency by lowering energy costs by 51.2%, and 67.8%, respectively. Similarly, the comfort costs for deviation from setpoint are enhanced by 54.4%, and 62.4%, respectively. It is determined that GA-F-PID performs better in local from than global form.

  10. Dynamic Modeling and Control of Electromechanical Coupling for Mechanical Elastic Energy Storage System

    Directory of Open Access Journals (Sweden)

    Yang Yu

    2013-01-01

    Full Text Available The structural scheme of mechanical elastic energy storage (MEES system served by permanent magnet synchronous motor (PMSM and bidirectional converters is designed. The aim of the research is to model and control the complex electromechanical system. The mechanical device of the complex system is considered as a node in generalized coordinate system, the terse nonlinear dynamic model of electromechanical coupling for the electromechanical system is constructed through Lagrange-Maxwell energy method, and the detailed deduction of the mathematical model is presented in the paper. The theory of direct feedback linearization (DFL is applied to decouple the nonlinear dynamic model and convert the developed model from nonlinear to linear. The optimal control theory is utilized to accomplish speed tracking control for the linearized system. The simulation results in three different cases show that the proposed nonlinear dynamic model of MEES system is correct; the designed algorithm has a better control performance in contrast with the conventional PI control.

  11. Transactive control: a framework for operating power systems characterized by high penetration of distributed energy resources

    DEFF Research Database (Denmark)

    Hu, Junjie; Yang, Guangya; Kok, Koen

    2016-01-01

    The increasing number of distributed energy resources connected to power systems raises operational challenges for the network operator, such as introducing grid congestion and voltage deviations in the distribution network level, as well as increasing balancing needs at the whole system level......, followed by a literature review and demonstration projects that apply to transactive control. Cases are then presented to illustrate the transactive control framework. At the end, discussions and research directions are presented, for applying transactive control to operating power systems, characterized...

  12. Optimal sizing and control strategy of isolated grid with wind power and energy storage system

    International Nuclear Information System (INIS)

    Luo, Yi; Shi, Lin; Tu, Guangyu

    2014-01-01

    Highlights: • An energy storage sizing scheme for wind powered isolated grid is developed. • A bi-level control strategy for wind-battery isolated grid is proposed. • The energy storage type selection method for Nan’ao island grid is presented. • The sizing method and the control strategy are verified based on the Nan’ao island. • The wind-battery demonstration system has great benefit for remote areas. - Abstract: Integrating renewable energy and energy storage system provides a prospective way for power supply of remote areas. Focused on the isolated grids comprising renewable energy generation and energy storage, an energy storage sizing method for taking account of the reliability requirement and a bi-level control strategy of the isolated grids are presented in this paper. Based on comparative analysis of current energy storage characteristics and practicability, Sodium–sulfur battery is recommended for power balance control in the isolated grids. The optimal size of the energy storage system is determined by genetic algorithm and sequential simulation. The annualized cost considering the compensation cost of curtailed wind power and load is minimized when the reliability requirement can be satisfied. The sizing method emphasizes the tradeoff between energy storage size and reliability of power supply. The bi-level control strategy is designed as upper level wide area power balance control in dispatch timescale and lower level battery energy storage system V/f control in real-time range for isolated operation. The mixed timescale simulation results of Nan’ao Island grid verify the effectiveness of the proposed sizing method and control strategy

  13. Peak Power Control with an Energy Management System

    Science.gov (United States)

    2013-03-01

    EMS. .....................18  Figure 17.  Circuit schematic implemented in the Simulink model. ..................................18  Figure 18.  The...21  Figure 20.  The non-critical load block implementation ...Modulation SCR Silicon Controller Rectifier SDC Student Design Center TTL Transistor Transistor Logic USB Universal Serial Bus VHDL VHSIC Hardware

  14. A control-oriented model for combined building climate comfort and aquifer thermal energy storage system

    NARCIS (Netherlands)

    Rostampour Samarin, Vahab; Bloemendal, J.M.; Jaxa-Rozen, M.; Keviczky, T.

    2016-01-01

    This paper presents a control-oriented model for combined building climate comfort and aquifer thermal energy storage (ATES) system. In particular, we first provide a description of building operational systems together with control framework variables. We then focus on the derivation of an

  15. An Optimal Control Method for Maximizing the Efficiency of Direct Drive Ocean Wave Energy Extraction System

    Science.gov (United States)

    Chen, Zhongxian; Yu, Haitao; Wen, Cheng

    2014-01-01

    The goal of direct drive ocean wave energy extraction system is to convert ocean wave energy into electricity. The problem explored in this paper is the design and optimal control for the direct drive ocean wave energy extraction system. An optimal control method based on internal model proportion integration differentiation (IM-PID) is proposed in this paper though most of ocean wave energy extraction systems are optimized by the structure, weight, and material. With this control method, the heavy speed of outer heavy buoy of the energy extraction system is in resonance with incident wave, and the system efficiency is largely improved. Validity of the proposed optimal control method is verified in both regular and irregular ocean waves, and it is shown that IM-PID control method is optimal in that it maximizes the energy conversion efficiency. In addition, the anti-interference ability of IM-PID control method has been assessed, and the results show that the IM-PID control method has good robustness, high precision, and strong anti-interference ability. PMID:25152913

  16. Energy Center Structure Optimization by using Smart Technologies in Process Control System

    Science.gov (United States)

    Shilkina, Svetlana V.

    2018-03-01

    The article deals with practical application of fuzzy logic methods in process control systems. A control object - agroindustrial greenhouse complex, which includes its own energy center - is considered. The paper analyzes object power supply options taking into account connection to external power grids and/or installation of own power generating equipment with various layouts. The main problem of a greenhouse facility basic process is extremely uneven power consumption, which forces to purchase redundant generating equipment idling most of the time, which quite negatively affects project profitability. Energy center structure optimization is largely based on solving the object process control system construction issue. To cut investor’s costs it was proposed to optimize power consumption by building an energy-saving production control system based on a fuzzy logic controller. The developed algorithm of automated process control system functioning ensured more even electric and thermal energy consumption, allowed to propose construction of the object energy center with a smaller number of units due to their more even utilization. As a result, it is shown how practical use of microclimate parameters fuzzy control system during object functioning leads to optimization of agroindustrial complex energy facility structure, which contributes to a significant reduction in object construction and operation costs.

  17. An optimal control method for maximizing the efficiency of direct drive ocean wave energy extraction system.

    Science.gov (United States)

    Chen, Zhongxian; Yu, Haitao; Wen, Cheng

    2014-01-01

    The goal of direct drive ocean wave energy extraction system is to convert ocean wave energy into electricity. The problem explored in this paper is the design and optimal control for the direct drive ocean wave energy extraction system. An optimal control method based on internal model proportion integration differentiation (IM-PID) is proposed in this paper though most of ocean wave energy extraction systems are optimized by the structure, weight, and material. With this control method, the heavy speed of outer heavy buoy of the energy extraction system is in resonance with incident wave, and the system efficiency is largely improved. Validity of the proposed optimal control method is verified in both regular and irregular ocean waves, and it is shown that IM-PID control method is optimal in that it maximizes the energy conversion efficiency. In addition, the anti-interference ability of IM-PID control method has been assessed, and the results show that the IM-PID control method has good robustness, high precision, and strong anti-interference ability.

  18. Multi-Agent System based Event-Triggered Hybrid Controls for High-Security Hybrid Energy Generation Systems

    DEFF Research Database (Denmark)

    Dou, Chun-Xia; Yue, Dong; Guerrero, Josep M.

    2017-01-01

    This paper proposes multi-agent system based event- triggered hybrid controls for guaranteeing energy supply of a hybrid energy generation system with high security. First, a mul-ti-agent system is constituted by an upper-level central coordi-nated control agent combined with several lower......-level unit agents. Each lower-level unit agent is responsible for dealing with internal switching control and distributed dynamic regula-tion for its unit system. The upper-level agent implements coor-dinated switching control to guarantee the power supply of over-all system with high security. The internal...

  19. Design of scanning motion control system for high-energy X-ray industrial CT

    International Nuclear Information System (INIS)

    Duan Liming

    2008-01-01

    A scanning motion control system was developed for the high-energy X-ray industrial computerized tomography (CT). The system consists of an industrial control computer, a counter card, a control card, servo drivers, servo motors, working platforms, gratings and control software. Based on windows driver model(WDM) mode, the composition of the driver pro- gram for the system was studied. Took the motor control card as an example, the method to develop the driver program was researched, and the intercourse process between the device driver program and the user-program was analyzed. The real-time control of the system was implemented using the WDM driver. The real-time performance and reliability of the system can satisfy the requirement of high-energy X-ray industrial CT. (authors)

  20. A novel integrated renewable energy system modelling approach, allowing fast FPGA controller prototyping

    DEFF Research Database (Denmark)

    Teodorescu, Remus; Ruiz, Alberto Parera; Cirstea, Marcian

    2008-01-01

    The paper describes a new holistic approach to the modeling of integrated renewable energy systems. The method is using the DK5 modeling/design environment from Celoxica and is based on the new Handel-C programming language. The goal of the work carried out was to achieve a combined model...... containing a Xilinx Spartan II FPGA and was successfully experimentally tested. This approach enables the design and fast hardware implementation of efficient controllers for Distributed Energy Resource (DER) hybrid systems....... of a photovoltaic energy system and a wind power system, which would allow an optimized holistic digital control system design, followed by rapid prototyping of the controller into a single Field Programmable Gate Array (FPGA). Initially, the system was simulated using Matlab / Simulink, to create a reference...

  1. Energy Management Systems and tertiary regulation in hierarchical control architectures for islanded micro-grids

    DEFF Research Database (Denmark)

    Sanseverino, Eleonora Riva; Di Silvestre, Maria Luisa; Quang, Ninh Nguyen

    2015-01-01

    In this paper, the structure of the highest level of a hierarchical control architecture for micro-grids is proposed. Such structure includes two sub-levels: the Energy Management System, EMS, and the tertiary regulation. The first devoted to energy resources allocation in each time slot based...

  2. A Wireless Power Sharing Control Strategy for Hybrid Energy Storage Systems in DC Microgrids

    DEFF Research Database (Denmark)

    Yang, Jie; Jin, Xinmin; Wu, Xuezhi

    2017-01-01

    In order to compensate multiple time scales power fluctuation resulted from distributed energy resources and loads, hybrid energy storage systems are employed as the buffer unit in DC microgrid. In this paper, a wireless hierarchical control strategy is proposed to realize power sharing between...

  3. Systems and methods for controlling energy use during a demand limiting period

    Science.gov (United States)

    Wenzel, Michael J.; Drees, Kirk H.

    2016-04-26

    Systems and methods for limiting power consumption by a heating, ventilation, and air conditioning (HVAC) subsystem of a building are shown and described. A feedback controller is used to generate a manipulated variable based on an energy use setpoint and a measured energy use. The manipulated variable may be used for adjusting the operation of an HVAC device.

  4. Energy systems

    International Nuclear Information System (INIS)

    Haefele, W.

    1974-01-01

    Up to the present the production, transmission and distribution of energy has been considered mostly as a fragmented problem; at best only subsystems have been considered. Today the scale of energy utilization is increasing rapidly, and correspondingly, the reliance of societies on energy. Such strong quantitative increases influence the qualitative nature of energy utilization in most of its aspects. Resources, reserves, reliability and environment are among the key words that may characterize the change in the nature of the energy utilization problem. Energy can no longer be considered an isolated technical and economical problem, rather it is embedded in the ecosphere and the society-technology complex. Restraints and boundary conditions have to be taken into account with the same degree of attention as in traditional technical problems, for example a steam turbine. This results in a strong degree of interweaving. Further, the purpose of providing energy becomes more visible, that is, to make survival possible in a civilized and highly populated world on a finite globe. Because of such interweaving and finiteness it is felt that energy should be considered as a system and therefore the term 'energy systems' is used. The production of energy is only one component of such a system; the handling of energy and the embedding of energy into the global and social complex in terms of ecology, economy, risks and resources are of similar importance. he systems approach to the energy problem needs more explanation. This paper is meant to give an outline of the underlying problems and it is hoped that by so doing the wide range of sometimes confusing voices about energy can be better understood. Such confusion starts already with the term 'energy crisis'. Is there an energy crisis or not? Much future work is required to tackle the problems of energy systems. This paper can only marginally help in that respect. But it is hoped that it will help understand the scope of the

  5. Energy systems

    Energy Technology Data Exchange (ETDEWEB)

    Haefele, W [Nuclear Research Centre, Applied Systems Analysis and Reactor Physics, Karlsruhe (Germany); International Institute for Applied Systems Analysis, Laxenburg (Austria)

    1974-07-01

    Up to the present the production, transmission and distribution of energy has been considered mostly as a fragmented problem; at best only subsystems have been considered. Today the scale of energy utilization is increasing rapidly, and correspondingly, the reliance of societies on energy. Such strong quantitative increases influence the qualitative nature of energy utilization in most of its aspects. Resources, reserves, reliability and environment are among the key words that may characterize the change in the nature of the energy utilization problem. Energy can no longer be considered an isolated technical and economical problem, rather it is embedded in the ecosphere and the society-technology complex. Restraints and boundary conditions have to be taken into account with the same degree of attention as in traditional technical problems, for example a steam turbine. This results in a strong degree of interweaving. Further, the purpose of providing energy becomes more visible, that is, to make survival possible in a civilized and highly populated world on a finite globe. Because of such interweaving and finiteness it is felt that energy should be considered as a system and therefore the term 'energy systems' is used. The production of energy is only one component of such a system; the handling of energy and the embedding of energy into the global and social complex in terms of ecology, economy, risks and resources are of similar importance. he systems approach to the energy problem needs more explanation. This paper is meant to give an outline of the underlying problems and it is hoped that by so doing the wide range of sometimes confusing voices about energy can be better understood. Such confusion starts already with the term 'energy crisis'. Is there an energy crisis or not? Much future work is required to tackle the problems of energy systems. This paper can only marginally help in that respect. But it is hoped that it will help understand the scope of the

  6. Energy Management System Based on Fuzzy fractional order PID Controller for Transient Stability Improvement in Microgrids with Energy Storage

    DEFF Research Database (Denmark)

    Moafi, Milad; Marzband, Mousa; Savaghebi, Mehdi

    2016-01-01

    in the islanded Microgrid (MG). To increase performance for a wide range of power system operating conditions, an energy management systems (EMS) is proposed based on a fuzzy fractional order PID (FFOPID) controller. It is able to analyze and simulate the dynamic behavior in grid connected MGs. This controller...... is proposed in the MG encompassing distributed generation resources with “plug and play” ability. The performance of FFOPID controller is verified for frequency control purposes and to support internal bus voltage in both islanded and grid connected operating modes in accordance with the failure time. Energy...... combined with a PID-controller (termed as FLPID) and Fuzzy fractional order PID (termed as FFOPID) are implemented according to the characteristics and limitations of overloading and state of charge (SOC). The obtained results show good performance of FFOPID controllers by improving the transient stability...

  7. Robust Sliding Mode Control of Permanent Magnet Synchronous Generator-Based Wind Energy Conversion Systems

    Directory of Open Access Journals (Sweden)

    Guangping Zhuo

    2016-12-01

    Full Text Available The subject of this paper pertains to sliding mode control and its application in nonlinear electrical power systems as seen in wind energy conversion systems. Due to the robustness in dealing with unmodeled system dynamics, sliding mode control has been widely used in electrical power system applications. This paper presents first and high order sliding mode control schemes for permanent magnet synchronous generator-based wind energy conversion systems. The application of these methods for control using dynamic models of the d-axis and q-axis currents, as well as those of the high speed shaft rotational speed show a high level of efficiency in power extraction from a varying wind resource. Computer simulation results have shown the efficacy of the proposed sliding mode control approaches.

  8. Modeling and Coordinated Control Strategy of Large Scale Grid-Connected Wind/Photovoltaic/Energy Storage Hybrid Energy Conversion System

    Directory of Open Access Journals (Sweden)

    Lingguo Kong

    2015-01-01

    Full Text Available An AC-linked large scale wind/photovoltaic (PV/energy storage (ES hybrid energy conversion system for grid-connected application was proposed in this paper. Wind energy conversion system (WECS and PV generation system are the primary power sources of the hybrid system. The ES system, including battery and fuel cell (FC, is used as a backup and a power regulation unit to ensure continuous power supply and to take care of the intermittent nature of wind and photovoltaic resources. Static synchronous compensator (STATCOM is employed to support the AC-linked bus voltage and improve low voltage ride through (LVRT capability of the proposed system. An overall power coordinated control strategy is designed to manage real-power and reactive-power flows among the different energy sources, the storage unit, and the STATCOM system in the hybrid system. A simulation case study carried out on Western System Coordinating Council (WSCC 3-machine 9-bus test system for the large scale hybrid energy conversion system has been developed using the DIgSILENT/Power Factory software platform. The hybrid system performance under different scenarios has been verified by simulation studies using practical load demand profiles and real weather data.

  9. Design and control of mobile traction energy storage system; Auslegung und Steuerung mobiler Traktionsenergiespeicher

    Energy Technology Data Exchange (ETDEWEB)

    Lehnert, Martin; Klausner, Sven [Fraunhofer-Institut fuer Verkehrs- und Infrastruktursysteme IVI, Dresden (Germany). Abt. fuer Fahrzeug- und Verkehrssystemtechnik

    2009-07-01

    Energy storage systems in trams may contribute to a noticeable reduction of energy consumption. Whether this or another operating purpose is to be pursued by the use of an energy store, major importance must in any case be attached to the type of storage technology to be selected, the design of the storage system and the kind of storage control strategy to be used. The latter has an influence on the efficiency of the store usage. It is especially predicative control strategies that offer a high potential to this effect. (orig.)

  10. Robustness Improvement of Superconducting Magnetic Energy Storage System in Microgrids Using an Energy Shaping Passivity-Based Control Strategy

    Directory of Open Access Journals (Sweden)

    Rui Hou

    2017-05-01

    Full Text Available Superconducting magnetic energy storage (SMES systems, in which the proportional-integral (PI method is usually used to control the SMESs, have been used in microgrids for improving the control performance. However, the robustness of PI-based SMES controllers may be unsatisfactory due to the high nonlinearity and coupling of the SMES system. In this study, the energy shaping passivity (ESP-based control strategy, which is a novel nonlinear control based on the methodology of interconnection and damping assignment (IDA, is proposed for robustness improvement of SMES systems. A step-by-step design of the ESP-based method considering the robustness of SMES systems is presented. A comparative analysis of the performance between ESP-based and PI control strategies is shown. Simulation and experimental results prove that the ESP-based strategy achieves the stronger robustness toward the system parameter uncertainties than the conventional PI control. Besides, the use of ESP-based control method can reduce the eddy current losses of a SMES system due to the significant reduction of 2nd and 3rd harmonics of superconducting coil DC current.

  11. Dynamic performance improvement of standalone battery integrated PMSG wind energy system using proportional resonant controller

    Directory of Open Access Journals (Sweden)

    Dileep Kumar Varma Sagiraju

    2017-08-01

    Full Text Available The load voltage and frequency should be controlled under steady state and transient conditions in off grid applications. Power quality and power management is very important task for rural communities under erratic wind and load conditions. This paper presents a coordinated Proportional resonant (PR and battery energy controller for enhancement of power quality and power management in direct drive standalone wind energy system. The dynamic performance of standalone direct drive Permanent Magnet Synchronous Generator (PMSG is investigated with the proposed control scheme under various operating conditions such as fluctuating wind with step increase and decrease in wind velocity, balanced and unbalanced load conditions. The proposed PR control strategy with battery energy controller also ensures effective power balance between wind and battery source in order to fulfill the load demand. The superiority of the proposed control strategy is confirmed by comparing with the traditional vector control strategy under fluctuating wind and load conditions through MATLAB/SIMULINK platform.

  12. Damping of Low Frequency Oscillation in Power System using Robust Control of Superconductor Flywheel Energy Storage System

    International Nuclear Information System (INIS)

    Lee, Jung Pil; Kim, Han Gun

    2012-01-01

    In this paper, the robust superconductor flywheel energy storage system(SFESS) controller using H control theory was designed to damp low frequency oscillation of power system. The main advantage of the controller is that uncertainties of power system can be included at the stage of controller design. Both disturbance attenuation and robust stability for the power system were treated simultaneously by using mixed sensitivity problem. The robust stability and the performance for uncertainties of power system were represented by frequency weighted transfer function. To verify control performance of proposed SFESS controller using control, the closed loop eigenvalue and the damping ratio in dominant oscillation mode of power system were analyzed and nonlinear simulation for one-machine infinite bus system was performed under disturbance for various operating conditions. The results showed that the proposed SFESS controller was more robust than conventional power system stabilizer (PSS).

  13. Choreographing Cyber-Physical Distributed Control Systems for the Energy Sector

    DEFF Research Database (Denmark)

    López-Acosta, Hugo-Andrés; Heussen, Kai

    2017-01-01

    Energy Systems are facing a significant change in the way their management and control is conceived. With the introduction of distributed and renewable energy based resources, a shift to a more distributed operation paradigm is emerging, overturning the conventional top-down design and operation...... principles. This shift creates a demand for distributed control systems (DCS) to facilitate a more adaptive and efficient operation of power networks. One key challenge here is to ensure the required reliability of distributed control systems. Whereas proven strategies exist for reliable control...... for coordination of physical actions, with increasing distribution of such control, the reliability and degradation properties in response to communications issues become more important. We build on the notion of Quality Choreographies, a formal model for the development of failure-aware distributed systems...

  14. FPA Tuned Fuzzy Logic Controlled Synchronous Buck Converter for a Wave/SC Energy System

    Directory of Open Access Journals (Sweden)

    SAHIN, E.

    2017-02-01

    Full Text Available This paper presents a flower pollination algorithm (FPA tuned fuzzy logic controlled (FLC synchronous buck converter (SBC for an integrated wave/ supercapacitor (SC hybrid energy system. In order to compensate the irregular wave effects on electrical side of the wave energy converter (WEC, a SC unit charged by solar panels is connected in parallel to the WEC system and a SBC is controlled to provide more reliable and stable voltage to the DC load. In order to test the performance of the designed FLC, a classical proportional-integral-derivative (PID controller is also employed. Both of the controllers are optimized by FPA which is a pretty new optimization algorithm and a well-known optimization algorithm of which particle swarm optimization (PSO to minimize the integral of time weighted absolute error (ITAE performance index. Also, the other error-based objective functions are considered. The entire energy system and controllers are developed in Matlab/Simulink and realized experimentally. Real time applications are done through DS1104 Controller Board. The simulation and experimental results show that FPA tuned fuzzy logic controller provides lower value performance indices than conventional PID controller by reducing output voltage sags and swells of the wave/SC energy system.

  15. Model Predictive Control of Hybrid Thermal Energy Systems in Transport Refrigeration

    DEFF Research Database (Denmark)

    Shafiei, Seyed Ehsan; Alleyne, Andrew

    2015-01-01

    A predictive control scheme is designed to control a transport refrigeration system, such as a delivery truck, that includes a vapor compression cycle configured in parallel with a thermal energy storage (TES) unit. A novel approach to TES utilization is introduced and is based on the current...

  16. A new energy control system for the Sao Paulo 8UD pelletron

    International Nuclear Information System (INIS)

    Acquadro, J.C.; Schnitter, U.; Teles, A.P.; Pereira, D.; Sala, O.; Freitas, P.A.B.

    1986-01-01

    The conventional control slits of the analyzing magnet have been substituted by a new energy control system using a thin carbon foil, for the 8UD Pelletron of the Universidade de Sao Paulo. This report describes the preliminary tests and results. (orig.)

  17. Control System Development for Power Generation from Small-Scale Compressed Air Energy Storage

    Science.gov (United States)

    2017-06-01

    35  Figure 26  Control Program Flowchart ...Figure 26 Control Program Flowchart 1. Resetting Variables The Micro850 has internal memory that stores the last state of variables when power is...Research, Energy Systems Technology Evaluation Program (ESTEP), under the technical monitoring of Stacey Curtis, Marissa Brand and Richard Carlin 10

  18. A Review on Battery Charging and Discharging Control Strategies: Application to Renewable Energy Systems

    Directory of Open Access Journals (Sweden)

    Edison Banguero

    2018-04-01

    Full Text Available Energy storage has become a fundamental component in renewable energy systems, especially those including batteries. However, in charging and discharging processes, some of the parameters are not controlled by the battery’s user. That uncontrolled working leads to aging of the batteries and a reduction of their life cycle. Therefore, it causes an early replacement. Development of control methods seeks battery protection and a longer life expectancy, thus the constant-current–constant-voltage method is mostly used. However, several studies show that charging time can be reduced by using fuzzy logic control or model predictive control. Another benefit is temperature control. This paper reviews the existing control methods used to control charging and discharging processes, focusing on their impacts on battery life. Classical and modern methods are studied together in order to find the best approach to real systems.

  19. Coordinated Secondary Control for Balanced Discharge Rate of Energy Storage System in Islanded AC Microgrids

    DEFF Research Database (Denmark)

    Guan, Yajuan; Quintero, Juan Carlos Vasquez; Guerrero, Josep M.

    2016-01-01

    A coordinated secondary control approach based on an autonomous current-sharing control strategy for balancing the discharge rates of energy storage systems (ESSs) in islanded AC microgrids is proposed in this paper. The coordinated secondary controller can regulate the power outputs of distributed...... incidents and unintentional outages in DG units, but also aims to provide a fast transient response and an accurate output-current-sharing performance. A complete root locus analysis is given in order to achieve system stability and parameter sensitivity. Experimental results are presented to show...... the performance of the whole system and to verify the effectiveness of the proposed controller....

  20. Design, analysis, operation, and advanced control of hybrid renewable energy systems

    Science.gov (United States)

    Whiteman, Zachary S.

    Because using non-renewable energy systems (e.g., coal-powered co-generation power plants) to generate electricity is an unsustainable, environmentally hazardous practice, it is important to develop cost-effective and reliable renewable energy systems, such as photovoltaics (PVs), wind turbines (WTs), and fuel cells (FCs). Non-renewable energy systems, however, are currently less expensive than individual renewable energy systems (IRESs). Furthermore, IRESs based on intermittent natural resources (e.g., solar irradiance and wind) are incapable of meeting continuous energy demands. Such shortcomings can be mitigated by judiciously combining two or more complementary IRESs to form a hybrid renewable energy system (HRES). Although previous research efforts focused on the design, operation, and control of HRESs has proven useful, no prior HRES research endeavor has taken a systematic and comprehensive approach towards establishing guidelines by which HRESs should be designed, operated, and controlled. The overall goal of this dissertation, therefore, is to establish the principles governing the design, operation, and control of HRESs resulting in cost-effective and reliable energy solutions for stationary and mobile applications. To achieve this goal, we developed and demonstrated four separate HRES principles. Rational selection of HRES type: HRES components and their sizes should be rationally selected using knowledge of component costs, availability of renewable energy resources, and expected power demands of the application. HRES design: by default, the components of a HRES should be arranged in parallel for increased efficiency and reliability. However, a series HRES design may be preferred depending on the operational considerations of the HRES components. HRES control strategy selection: the choice of HRES control strategy depends on the dynamics of HRES components, their operational considerations, and the practical limitations of the HRES end-use. HRES data

  1. A multiobjective ? control strategy for energy harvesting in regenerative vehicle suspension systems

    Science.gov (United States)

    Casavola, Alessandro; Di Iorio, Fabio; Tedesco, Francesco

    2018-04-01

    A significant amount of energy induced by road unevenness and vehicle roll and pitch motions is usually dissipated by conventional shock-absorbers. In this paper, a novel active multiobjective ? control design methodology is proposed which explicitly includes, besides the usual control objectives on ride comfort, road handling and suspension stroke, the amount of energy to be harvested as an additional, though conflicting, control objective and allows the designer to directly trade-off among them depending on the application. An electromechanical regenerative suspension system is considered where the viscous damper is replaced by a linear electrical motor which is actively governed. It is shown that the proposed control law is able to achieve remarkable improvements on the amount of the harvested energy with respect to passive or semi-active control strategies while maintaining the other objectives at acceptable levels. Simulative studies undertaken via CarSim are also reported that confirm the potentiality and flexibility of the proposed control design strategy.

  2. Implementation of EPICS based vacuum control system for variable energy cyclotron centre, Kolkata

    Science.gov (United States)

    Roy, Anindya; Bhole, R. B.; Nandy, Partha P.; Yadav, R. C.; Pal, Sarbajit; Roy, Amitava

    2015-03-01

    The vacuum system of the Room Temperature (K = 130) Cyclotron of Variable Energy Cyclotron Centre is comprised of vacuum systems of main machine and Beam Transport System. The vacuum control system is upgraded to a PLC based Automated system from the initial relay based Manual system. The supervisory control of the vacuum system is implemented in Experimental Physics and Industrial Control System (EPICS). An EPICS embedded ARM based vacuum gauge controller is developed to mitigate the requirement of vendor specific gauge controller for gauges and also for seamless integration of the gauge controllers with the control system. A set of MS-Windows ActiveX components with embedded EPICS Channel Access interface are developed to build operator interfaces with less complex programming and to incorporate typical Windows feature, e.g., user authentication, file handling, better fonts, colors, mouse actions etc. into the operator interfaces. The control parameters, monitoring parameters, and system interlocks of the system are archived in MySQL based EPICS MySQL Archiver developed indigenously. In this paper, we describe the architecture, the implementation details, and the performance of the system.

  3. Implementation of EPICS based vacuum control system for variable energy cyclotron centre, Kolkata

    Energy Technology Data Exchange (ETDEWEB)

    Roy, Anindya, E-mail: r-ani@vecc.gov.in; Bhole, R. B.; Nandy, Partha P.; Yadav, R. C.; Pal, Sarbajit; Roy, Amitava [Variable Energy Cyclotron Centre, 1/AF Bidhan Nagar, Kolkata 700064 (India)

    2015-03-15

    The vacuum system of the Room Temperature (K = 130) Cyclotron of Variable Energy Cyclotron Centre is comprised of vacuum systems of main machine and Beam Transport System. The vacuum control system is upgraded to a PLC based Automated system from the initial relay based Manual system. The supervisory control of the vacuum system is implemented in Experimental Physics and Industrial Control System (EPICS). An EPICS embedded ARM based vacuum gauge controller is developed to mitigate the requirement of vendor specific gauge controller for gauges and also for seamless integration of the gauge controllers with the control system. A set of MS-Windows ActiveX components with embedded EPICS Channel Access interface are developed to build operator interfaces with less complex programming and to incorporate typical Windows feature, e.g., user authentication, file handling, better fonts, colors, mouse actions etc. into the operator interfaces. The control parameters, monitoring parameters, and system interlocks of the system are archived in MySQL based EPICS MySQL Archiver developed indigenously. In this paper, we describe the architecture, the implementation details, and the performance of the system.

  4. Implementation of EPICS based vacuum control system for variable energy cyclotron centre, Kolkata

    International Nuclear Information System (INIS)

    Roy, Anindya; Bhole, R. B.; Nandy, Partha P.; Yadav, R. C.; Pal, Sarbajit; Roy, Amitava

    2015-01-01

    The vacuum system of the Room Temperature (K = 130) Cyclotron of Variable Energy Cyclotron Centre is comprised of vacuum systems of main machine and Beam Transport System. The vacuum control system is upgraded to a PLC based Automated system from the initial relay based Manual system. The supervisory control of the vacuum system is implemented in Experimental Physics and Industrial Control System (EPICS). An EPICS embedded ARM based vacuum gauge controller is developed to mitigate the requirement of vendor specific gauge controller for gauges and also for seamless integration of the gauge controllers with the control system. A set of MS-Windows ActiveX components with embedded EPICS Channel Access interface are developed to build operator interfaces with less complex programming and to incorporate typical Windows feature, e.g., user authentication, file handling, better fonts, colors, mouse actions etc. into the operator interfaces. The control parameters, monitoring parameters, and system interlocks of the system are archived in MySQL based EPICS MySQL Archiver developed indigenously. In this paper, we describe the architecture, the implementation details, and the performance of the system

  5. Integrated wireless sensor network and real time smart controlling and monitoring system for efficient energy management in standalone photovoltaic systems

    Science.gov (United States)

    Abou-Elnour, Ali; Thabt, A.; Helmy, S.; Kashf, Y.; Hadad, Y.; Tarique, M.; Abo-Elnor, Ossama

    2014-04-01

    In the present work, wireless sensor network and smart real-time controlling and monitoring system are integrated for efficient energy management of standalone photovoltaic system. The proposed system has two main components namely the monitoring and controlling system and the wireless communication system. LabView software has been used in the implementation of the monitoring and controlling system. On the other hand, ZigBee wireless modules have been used to implement the wireless system. The main functions of monitoring and controlling unit is to efficiently control the energy consumption form the photovoltaic system based on accurate determination of the periods of times at which the loads are required to be operated. The wireless communication system send the data from the monitoring and controlling unit to the loads at which desired switching operations are performed. The wireless communication system also continuously feeds the monitoring and controlling unit with updated input data from the sensors and from the photovoltaic module send to calculate and record the generated, the consumed, and the stored energy to apply load switching saving schemes if necessary. It has to be mentioned that our proposed system is a low cost and low power system because and it is flexible to be upgraded to fulfill additional users' requirements.

  6. Design and control strategy for a hybrid green energy system for mobile telecommunication sites

    Science.gov (United States)

    Okundamiya, Michael S.; Emagbetere, Joy O.; Ogujor, Emmanuel A.

    2014-07-01

    The rising energy costs and carbon footprint of operating mobile telecommunication sites in the emerging world have increased research interests in green technology. The intermittent nature of most green energy sources creates the problem of designing the optimum configuration for a given location. This study presents the design analysis and control strategy for a cost effective and reliable operation of the hybrid green energy system (HGES) for GSM base transceiver station (BTS) sites in isolated regions. The design constrains the generation and distribution of power to reliably satisfy the energy demand while ensuring safe operation of the system. The overall process control applies the genetic algorithm-based technique for optimal techno-economic sizing of system's components. The process simulation utilized meteorological data for 3 locations (Abuja, Benin City and Sokoto) with varying climatic conditions in Nigeria. Simulation results presented for green GSM BTS sites are discussed and compared with existing approaches.

  7. Control of Refrigeration Systems for Trade-off between Energy Consumption and Food Quality Loss

    DEFF Research Database (Denmark)

    Cai, Junping

    In supermarkets, control strategies determine both the energy consumption of refrigeration systems and the quality loss of refrigerated foodstuffs. The question is, what can be done to optimize the balance between quality loss and energy consumption? This thesis tries to answer this question...... by applying two main optimization strategies to traditional refrigeration systems. The first strategy is a new defrost-on-demand scheme, which based on an objective function between quality loss and energy consumption, continuously seeks an optimal time interval for defrosting in dynamic situation. The second...... strategy is through utilization of the thermal mass of the refrigerated foodstuffs, the day-night temperature variation and the capacity control of the compressor, to realize a trade-off between system energy consumption and food quality loss....

  8. Control of Flywheel Energy Storage Systems in Electrical Vehicle Charging Stations

    DEFF Research Database (Denmark)

    Sun, Bo

    energy storage system (FESS). The proposed PhD project supports a corresponding smart control strategy that could be termed “charging station to grid (CS2G)”. It explores the possibility of using a dedicated energy storage system (FESS) within the charging station to alleviate grid and market conditions...... converters is built and analyzed. |Based on modeling analysis, centralized and distributed control methods are both explored to realize the coordination control of each components in the system. Specially, this project proposes a “dc voltage vs speed” droop strategy for FESS control based on distributed bus...... function method when the system switches its operation behavior between two modes. Finally, a downscaled FCS prototype with FESS is built in the intelligent MG lab, and experiments and hardware-in-loop simulation results are conducted to verify the effectiveness and feasibility with the proposed FCS...

  9. Speed-sensorless control strategy for multi-phase induction generator in wind energy conversion systems

    Directory of Open Access Journals (Sweden)

    Dumnić Boris P.

    2016-01-01

    Full Text Available Renewable energy sources, especially wind energy conversion systems (WECS, exhibit constant growth. Increase in power and installed capacity led to advances in WECS topologies. Multi-phase approach presents a new development direction, with several key advantages over three-phase systems. Paired with a sensorless control strategy, multi-phase machines are expected to take primacy over standard solutions. This paper presents speed sensorless vector control of an asymmetrical six-phase induction generator based on a model reference adaptive system (MRAS. Suggested topology and developed control algorithm show that sensorless control can yield appropriate dynamic characteristics for the use in WECS with increase in reliability and robustness. [Projekat Ministarstva nauke Republike Srbije, br. III 042004: Smart Electricity Distribution Grids Based on Distribution Management System and Distributed Generation

  10. Optimization of Thermal Object Nonlinear Control Systems by Energy Efficiency Criterion.

    Science.gov (United States)

    Velichkin, Vladimir A.; Zavyalov, Vladimir A.

    2018-03-01

    This article presents the results of thermal object functioning control analysis (heat exchanger, dryer, heat treatment chamber, etc.). The results were used to determine a mathematical model of the generalized thermal control object. The appropriate optimality criterion was chosen to make the control more energy-efficient. The mathematical programming task was formulated based on the chosen optimality criterion, control object mathematical model and technological constraints. The “maximum energy efficiency” criterion helped avoid solving a system of nonlinear differential equations and solve the formulated problem of mathematical programming in an analytical way. It should be noted that in the case under review the search for optimal control and optimal trajectory reduces to solving an algebraic system of equations. In addition, it is shown that the optimal trajectory does not depend on the dynamic characteristics of the control object.

  11. Energy-optimal speed control of fans and compressor in a refrigeration system

    DEFF Research Database (Denmark)

    Jakobsen, Arne; Rasmussen, Bjarne D.

    1998-01-01

    Use of variable speed compressors and variable speed fans for both the evaporator and the condenser makes the refrigeration system more flexible, adds to the degree of freedom of the control system and therefore makes it possible to (on-line) optimise the various speeds involved. Say, for example...... and therefore the achievement of the potential for energy saving. This control/optimisation problem is investigated using a steady-state simulation model....

  12. Hierarchical energy management system for stand-alone hybrid system based on generation costs and cascade control

    International Nuclear Information System (INIS)

    Torreglosa, J.P.; García, P.; Fernández, L.M.; Jurado, F.

    2014-01-01

    Highlights: • We present an energy management system for a stand-alone WT/PV/hydrogen/battery hybrid system. • Hierarchical control composed by master and slave control strategies. • Control assures reliable electricity support for stand-alone applications subject to technical and economic criteria. - Abstract: This paper presents an energy management system (EMS) for stand-alone hybrid systems composed by photovoltaic (PV) solar panels and a wind turbine (WT) as primary energy sources and two energy storage systems, which are a hydrogen system and a battery. The hydrogen system is composed of fuel cell (FC), electrolyzer and hydrogen storage tank. The EMS is a hierarchical control composed by a master control strategy and a slave control strategy. On the one hand, the master control generates the reference powers to meet several premises (such as to satisfy the load power demand, and to maintain the hydrogen tank level and the state of charge (SOC) of the battery between their target margins), taking also into account economic aspects to discriminate between using the battery or hydrogen system. On the other hand, the slave control modifies the reference powers generated by the master control according to the energy sources dynamic limitations, and maintains the DC bus voltage at its reference value. The models, implemented in MATLAB-Simulink environment, have been developed from commercially available components. To check the viability of the proposed EMS, two kinds of simulations were carried out: (1) A long-term simulation of 25 years (expected lifetime of the system) with a sample time of one hour to validate the master control of the EMS; and (2) A short-term simulation with sudden net power variations to validate the slave control of the EMS

  13. Energy conservation. Purposeful regulation and control systems for gas infrared radiation heating

    Energy Technology Data Exchange (ETDEWEB)

    Reitsch, L [GoGaS Goch G.m.b.H. und Co., Dortmund (Germany, F.R.)

    1978-01-01

    Gas infrared radiators have been in use for a long time for heating large halls of trade and industrial buildings as well as sport centers. The success of this heating system is based mainly on considerably reduced energy consumption as against convective heating systems. However, the biggest energy savings can be achieved when heating systems of this kind are equipped with regulation and control systems which are adapted to the way the rooms are used. Solutions to problems are described and information is given for planning.

  14. A distributed control approach for power and energy management in a notional shipboard power system

    Science.gov (United States)

    Shen, Qunying

    The main goal of this thesis is to present a power control module (PCON) based approach for power and energy management and to examine its control capability in shipboard power system (SPS). The proposed control scheme is implemented in a notional medium voltage direct current (MVDC) integrated power system (IPS) for electric ship. To realize the control functions such as ship mode selection, generator launch schedule, blackout monitoring, and fault ride-through, a PCON based distributed power and energy management system (PEMS) is developed. The control scheme is proposed as two-layer hierarchical architecture with system level on the top as the supervisory control and zonal level on the bottom as the decentralized control, which is based on the zonal distribution characteristic of the notional MVDC IPS that was proposed as one of the approaches for Next Generation Integrated Power System (NGIPS) by Norbert Doerry. Several types of modules with different functionalities are used to derive the control scheme in detail for the notional MVDC IPS. Those modules include the power generation module (PGM) that controls the function of generators, the power conversion module (PCM) that controls the functions of DC/DC or DC/AC converters, etc. Among them, the power control module (PCON) plays a critical role in the PEMS. It is the core of the control process. PCONs in the PEMS interact with all the other modules, such as power propulsion module (PPM), energy storage module (ESM), load shedding module (LSHED), and human machine interface (HMI) to realize the control algorithm in PEMS. The proposed control scheme is implemented in real time using the real time digital simulator (RTDS) to verify its validity. To achieve this, a system level energy storage module (SESM) and a zonal level energy storage module (ZESM) are developed in RTDS to cooperate with PCONs to realize the control functionalities. In addition, a load shedding module which takes into account the reliability

  15. An Energy-Based Control Strategy for Battery Energy Storage Systems: A Case Study on Microgrid Applications

    Directory of Open Access Journals (Sweden)

    Rui Hou

    2017-02-01

    Full Text Available Battery energy storage systems (BESSs with proportional-integral (PI control methods have been widely studied in microgrids (MGs. However, the performance of PI control methods might be unsatisfactory for BESSs due to the nonlinear characteristics of the system. To overcome this problem, an energy-based (EB control method is applied to control the converter of a BESS in this study. The EB method is a robust nonlinear control method based on passivity theory with good performance in both transient and steady states. The detailed design process of the EB method in the BESS by adopting an interconnection and damping assignment (IDA strategy is described. The design process comprises three steps: the construction of the port-controlled Hamiltonian model, the determination of the equilibrium point and the solution of the undetermined matrix. In addition, integral action is combined to eliminate the steady state error generated by the model mismatch. To establish the correctness and validity of the proposed method, we implement several case simulation studies based on a test MG system and compare the control performance of the EB and PI methods carefully. The case simulation results demonstrate that the EB method has better tracking and anti-disturbance performance compared with the classic PI method. Moreover, the proposed EB method shows stronger robustness to the uncertainty of system parameters.

  16. Coordinated Secondary Control for Balanced Discharge Rate of Energy Storage System in Islanded Microgrids

    DEFF Research Database (Denmark)

    Guan, Yajuan; Guerrero, Josep M.; Quintero, Juan Carlos Vasquez

    2015-01-01

    current and unintentional outage of DGs. Thus, the stability and reliability of islanded MG can be improved. The eigenvalues and root locus with the proposed controller are presented to design the parameters as well as analyzing the system stability. Simulation results based on Matlab......A coordinated secondary control based on a novel autonomous currents sharing control strategy for balanced discharge rate of energy storage systems in islanded microgrid (MG) is proposed in this paper. The coordinated secondary controller is able to regulate the output power of distributed...... generating (DG) systems according to their state-of-charge by adjusting the virtual resistances of their voltage controlled inverters. This controller can not only provide the faster response and accurate output current sharing control, but also avoid the potential operation failure resulting from the over...

  17. Research on Control Strategy of the Micro Grid’s Hybrid Energy System

    Science.gov (United States)

    Gao, Zi-jun; Li, Yang; Wang, Yan-ping; Zong, Ke-yong; Zhang, Jing

    2018-03-01

    This paper study the structure and operating characteristic of the hybrid energy system which is made of super-capacitor and battery. The system is controlled by strategy of bus voltage following. The bus voltage can change the state from swings to stable quickly when load mutation occurs in the micro grid. The transient impact also can be reduced by this way. The passage set up the model of energy system and make an analysis by the software named MATLAB/Simulink. At last, the passage proves the correctness and the effectiveness of the control strategy and draws a conclusion that the transient impact can be inhibited which occurs in the bus voltage of energy system.

  18. A Fuzzy-Logic Subsumption Controller for Home Energy Management Systems

    Energy Technology Data Exchange (ETDEWEB)

    Ainstworth, Nathan; Johnson, Brian; Lundstrom, Blake

    2015-10-05

    Presentation for NAPS 2015 associated with conference publication CP-64392. Home Energy Management Systems (HEMS) are controllers that manage and coordinate the generation, storage, and loads in a home. These controllers are increasingly necessary to ensure that increasing penetrations of distributed energy resources are used effectively and do not disrupt the operation of the grid. In this paper, we propose a novel approach to HEMS design based on behavioral control methods, which do not require accurate models or predictions and are very responsive to changing conditions.

  19. Designing an Energy Storage System Fuzzy PID Controller for Microgrid Islanded Operation

    Directory of Open Access Journals (Sweden)

    Jin-Hong Jeon

    2011-09-01

    Full Text Available Recently, interest in microgrids, which are composed of distributed generation (DG, distributed storage (DS, and loads, has been growing as a potentially effective clean energy system to mitigate against climate change. The microgrid is operated in the grid-connected mode and the islanded mode according to the conditions of the upstream power grid. The role of the energy storage system (ESS is especially important to maintain constant the frequency and voltage of an islanded microgrid. For this reason, various approaches for ESS control have been put forth. In this paper, a fuzzy PID controller is proposed to improve the frequency control performance of the ESS. This fuzzy PID controller consists of a fuzzy logic controller and a conventional PI controller, connected in series. The fuzzy logic controller has two input signals, and then the output signal of the fuzzy logic controller is the input signal of the conventional PI controller. For comparison of control performance, gains of each PI controller and fuzzy PID controller are tuned by the particle swam optimization (PSO algorithm. In the simulation study, the control performance of the fuzzy PID was also tested under various operating conditions using the PSCAD/EMTDC simulation platform.

  20. An energy-saving nonlinear position control strategy for electro-hydraulic servo systems.

    Science.gov (United States)

    Baghestan, Keivan; Rezaei, Seyed Mehdi; Talebi, Heidar Ali; Zareinejad, Mohammad

    2015-11-01

    The electro-hydraulic servo system (EHSS) demonstrates numerous advantages in size and performance compared to other actuation methods. Oftentimes, its utilization in industrial and machinery settings is limited by its inferior efficiency. In this paper, a nonlinear backstepping control algorithm with an energy-saving approach is proposed for position control in the EHSS. To achieve improved efficiency, two control valves including a proportional directional valve (PDV) and a proportional relief valve (PRV) are used to achieve the control objectives. To design the control algorithm, the state space model equations of the system are transformed to their normal form and the control law through the PDV is designed using a backstepping approach for position tracking. Then, another nonlinear set of laws is derived to achieve energy-saving through the PRV input. This control design method, based on the normal form representation, imposes internal dynamics on the closed-loop system. The stability of the internal dynamics is analyzed in special cases of operation. Experimental results verify that both tracking and energy-saving objectives are satisfied for the closed-loop system. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.

  1. Assessment of control strategies for fault ride through of SCIG-based wind energy conversion systems

    Directory of Open Access Journals (Sweden)

    Manaullah

    2016-01-01

    Full Text Available With increasing penetration of wind energy into the power grid, researchers have started focusing more on control and coordination of wind energy conversion systems (WECS with the other components at system level, especially during fault. It is important to implement a suitable fault ride through control strategy to avoid tripping of the generators when the power system is subjected to voltage dips normally below 90% of nominal voltage. The dips below 90% may lead to a significant loss of generation and frequency collapse, followed by a blackout. This article implements and assesses the methodologies to deal with such situations for squirrel cage induction generator-based wind energy conversion systems employing fully rated power electronic converters. Three distinct control techniques—namely, balanced positive sequence control, positive negative sequence control, and dual current control—have been simulated and applied to grid side converter of SCIG-based WECS. The performance of all the three control strategies has been compared and presented in this work. During this study, the system is subjected to the most common unsymmetrical line to ground (LG fault and most severe symmetrical LLL fault on grid for the purpose of anaysis.

  2. Power electronics and control techniques for maximum energy harvesting in photovoltaic systems

    CERN Document Server

    Femia, Nicola

    2012-01-01

    Incentives provided by European governments have resulted in the rapid growth of the photovoltaic (PV) market. Many PV modules are now commercially available, and there are a number of power electronic systems for processing the electrical power produced by PV systems, especially for grid-connected applications. Filling a gap in the literature, Power Electronics and Control Techniques for Maximum Energy Harvesting in Photovoltaic Systems brings together research on control circuits, systems, and techniques dedicated to the maximization of the electrical power produced by a photovoltaic (PV) so

  3. A switched energy saving position controller for variable-pressure electro-hydraulic servo systems.

    Science.gov (United States)

    Tivay, Ali; Zareinejad, Mohammad; Rezaei, S Mehdi; Baghestan, Keivan

    2014-07-01

    The electro-hydraulic servo system (EHSS) demonstrates a relatively low level of efficiency compared to other available actuation methods. The objective of this paper is to increase this efficiency by introducing a variable supply pressure into the system and controlling this pressure during the task of position tracking. For this purpose, an EHSS structure with controllable supply pressure is proposed and its dynamic model is derived from the basic laws of physics. A switching control structure is then proposed to control both the supply pressure and the cylinder position at the same time, in a way that reduces the overall energy consumption of the system. The stability of the proposed switching control system is guaranteed by proof, and its performance is verified by experimental testing. Copyright © 2014 ISA. Published by Elsevier Ltd. All rights reserved.

  4. Demonstrating Hybrid Heat Transport and Energy Conversion System Performance Characterization Using Intelligent Control Systems

    International Nuclear Information System (INIS)

    Ostrum, Lee; Manic, Milos

    2017-01-01

    The debate continues on the magnitude and validity of climate change caused by human activities. However, there is no debate about the need to make buildings, modes of transportation, factories, and homes as energy efficient as possible. Given that climate change could occur with the wasteful use of fossil fuel and the fact that fossil energy costs could and will swing wildly, it is imperative that every effort be made to utilize energy sources to their fullest. Hybrid energy systems (HES) are two or more separate energy producers used together to produce energy commodities. The HES this report focuses on is the use of nuclear reactor waste heat as a source of further energy utilization. Nuclear reactors use a fluid to cool the core and produce the steam needed for the production of electricity. Traditionally this steam, or coolant, is used to convert the energy then cooled elsewhere. The heat is released into the environment without being used further. By adding technologies to nuclear reactors to use the wasted heat, a system can be developed to make more than just electricity and allow for loading following capabilities.

  5. Demonstrating Hybrid Heat Transport and Energy Conversion System Performance Characterization Using Intelligent Control Systems

    Energy Technology Data Exchange (ETDEWEB)

    Ostrum, Lee [Univ. of Idaho and Idaho Falls Center, Idaho Falls, ID (United States); Manic, Milos [Virginia Commonwealth Univ., Richmond, VA (United States)

    2017-09-28

    The debate continues on the magnitude and validity of climate change caused by human activities. However, there is no debate about the need to make buildings, modes of transportation, factories, and homes as energy efficient as possible. Given that climate change could occur with the wasteful use of fossil fuel and the fact that fossil energy costs could and will swing wildly, it is imperative that every effort be made to utilize energy sources to their fullest. Hybrid energy systems (HES) are two or more separate energy producers used together to produce energy commodities. The HES this report focuses on is the use of nuclear reactor waste heat as a source of further energy utilization. Nuclear reactors use a fluid to cool the core and produce the steam needed for the production of electricity. Traditionally this steam, or coolant, is used to convert the energy then cooled elsewhere. The heat is released into the environment without being used further. By adding technologies to nuclear reactors to use the wasted heat, a system can be developed to make more than just electricity and allow for loading following capabilities.

  6. Control Strategies to Reduce the Energy Consumption of Central Domestic Hot Water Systems

    Energy Technology Data Exchange (ETDEWEB)

    Dentz, Jordan [The Levy Partnership, Inc., New York, NY (United States). Advanced Residential Integrated Energy Solutions; Ansanelli, Eric [The Levy Partnership, Inc., New York, NY (United States). Advanced Residential Integrated Energy Solutions; Henderson, Hugh [The Levy Partnership, Inc., New York, NY (United States). Advanced Residential Integrated Energy Solutions; Varshney, Kapil [The Levy Partnership, Inc., New York, NY (United States). Advanced Residential Integrated Energy Solutions

    2016-06-23

    Domestic hot water (DHW) heating is the second largest energy end use in U.S. buildings, exceeded only by space conditioning. Recirculation systems consisting of a pump and piping loop(s) are commonly used in multifamily buildings to reduce wait time for hot water at faucets; however, constant pumping increases energy consumption by exposing supply and return line piping to continuous heat loss, even during periods when there is no demand for hot water. In this study, ARIES installed and tested two types of recirculation controls in a pair of buildings in order to evaluate their energy savings potential. Demand control, temperature modulation controls, and the simultaneous operation of both were compared to the baseline case of constant recirculation. Additionally, interactive effects between DHW control fuel reductions and space conditioning (heating and cooling) were estimated in order to make more realistic predictions of the payback and financial viability of retrofitting DHW systems with these controls. Results showed that DHW fuel consumption reduced by 7% after implementing the demand control technique, 2% after implementing temperature modulation, and 15% after implementing demand control and temperature modulation techniques simultaneously; recirculation pump runtime was reduced to 14 minutes or less per day. With space heating and cooling interactions included, the estimated annual cost savings were 8%, 1%, and 14% for the respective control techniques. Possible complications in the installation, commissioning and operation of the controls were identified and solutions offered.

  7. Control Strategies to Reduce the Energy Consumption of Central Domestic Hot Water Systems

    Energy Technology Data Exchange (ETDEWEB)

    Dentz, Jordan; Ansanelli, Eric; Henderson, Hugh; Varshney, Kapil

    2016-06-03

    Domestic hot water (DHW) heating is the second largest energy end use in U.S. buildings, exceeded only by space conditioning. Recirculation systems consisting of a pump and piping loop(s) are commonly used in multifamily buildings to reduce wait time for hot water at faucets; however, constant pumping increases energy consumption by exposing supply and return line piping to continuous heat loss, even during periods when there is no demand for hot water. In this study, ARIES installed and tested two types of recirculation controls in a pair of buildings in order to evaluate their energy savings potential. Demand control, temperature modulation controls, and the simultaneous operation of both were compared to the baseline case of constant recirculation. Additionally, interactive effects between DHW control fuel reductions and space conditioning (heating and cooling) were estimated in order to make more realistic predictions of the payback and financial viability of retrofitting DHW systems with these controls. Results showed that DHW fuel consumption reduced by 7% after implementing the demand control technique, 2% after implementing temperature modulation, and 15% after implementing demand control and temperature modulation techniques simultaneously; recirculation pump runtime was reduced to 14 minutes or less per day. With space heating and cooling interactions included, the estimated annual cost savings were 8%, 1%, and 14% for the respective control techniques. Possible complications in the installation, commissioning and operation of the controls were identified and solutions offered.

  8. Modeling and control of a small solar fuel cell hybrid energy system

    Institute of Scientific and Technical Information of China (English)

    LI Wei; ZHU Xin-jian; CAO Guang-yi

    2007-01-01

    This paper describes a solar photovoltaic fuel cell (PVEC) hybrid generation system consisting of a photovoltaic (PV) generator, a proton exchange membrane fuel cell (PEMFC), an electrolyser, a supercapacitor, a storage gas tank and power conditioning unit (PCU). The load is supplied from the PV generator with a fuel cell working in parallel. Excess PV energy when available is converted to hydrogen using an electrolyser for later use in the fuel cell. The individual mathematical model for each component is presented. Control strategy for the system is described. MATLAB/Simulink is used for the simulation of this highly nonlinear hybrid energy system. The simulation results are shown in the paper.

  9. Energy reduction for a dual circuit cooling water system using advanced regulatory control

    International Nuclear Information System (INIS)

    Muller, C.J.; Craig, I.K.

    2016-01-01

    Highlights: • Potentially reduce energy required by a dual circuit cooling water system by 30%. • Accomplished using an advanced regulatory control and switching strategy. • No formal process model is required. • Can be implemented on control system hardware commonly used in industry. - Abstract: Various process utilities are used in the petrochemical industry as auxiliary variables to facilitate the addition/removal of energy to/from the process, power process equipment and inhibit unwanted reaction. Optimisation activities usually focus on the process itself or on the utility consumption though the generation and distribution of these utilities are often overlooked in this regard. Many utilities are prepared or generated far from the process plant and have to be transported or transmitted, giving rise to more losses and potential inefficiencies. To illustrate the potential benefit of utility optimisation, this paper explores the control of a dual circuit cooling water system with focus on energy reduction subject process constraints. This is accomplished through the development of an advanced regulatory control (ARC) and switching strategy which does not require the development of a system model, only rudimentary knowledge of the behaviour of the process and system constraints. The novelty of this manuscript lies in the fact that it demonstrates that significant energy savings can be obtained by applying ARC to a process utility containing both discrete and continuous dynamics. Furthermore, the proposed ARC strategy does not require a plant model, uses only existing plant equipment, and can be implemented on control system hardware commonly used in industry. The simulation results indicate energy saving potential in the region of 30% on the system under investigation.

  10. Advanced experimental method for self-optimizing control system to a new energy converce plant

    International Nuclear Information System (INIS)

    Vasiliev, V.V.

    1992-01-01

    The progress in the development and studying of new methods of producing electric energy, based on direct conversion of heat, light, fuel or chemical energy into electric energy, raises the problem of more effective use of their power characteristics. In this paper, disclosure is made of a self-optimizing control system for an abject with a unimodal quality function. The system comprises an object, a divider, a band-pass filter, an averaging filter, a multiplier, a final control element, and adder and further includes a search signal generator. The fashion and the system are presented in the USSR No. 684510, in the USA No. 4179730, in France No. 2386854, in Germany No. 2814963, in Japan No. 1369882

  11. Efficient start–up energy management via nonlinear control for eco–traction systems

    International Nuclear Information System (INIS)

    Becherif, M.; Ramadan, H.S.; Ayad, M.Y.; Hissel, D.; Desideri, U.; Antonelli, M.

    2017-01-01

    Highlights: • Renewable HPS for the train start-up within feeding durations. • Dynamic modelling of the modern HPS applied to traction systems. • Port-Controlled Hamiltonian (PCH) design for supercapacitors’ charge/discharge operation. • Experimental validation and applicability of HPSs for energy management in eco-tractions. - Abstract: Electrochemical capacitors, called supercapacitors (SCs) or ultracapacitors, are devices conveniently used for embedded electrical energy management owing to their huge capacitance, low internal resistance and flexible control through power electronic conversion. This paper proposes a main power supply of hybrid Wind Generator (WG)–SC within the train station for feeding the traction onboard SC through specified limited feeding transit durations. Onboard SCs provide the train with the requested start–up self–energy. The hybrid WG–SCs system is an environmental–friendly source that enables the independency on national grid and guarantees an efficient bidirectional power transfer for energy management with enhanced dynamic performance. Therefore, the dynamic modelling and the experimental analysis of the modern hybrid WG–SCs used for managing the charge/discharge operation of SCs at Unity Power Factor (UPF) mode are presented. For this purpose, the Port–Controlled Hamiltonian (PCH) methodology is deduced and explicitly presented. Simulation results, via MATLAB™, reveal that the proposed PCH control methodology can be successfully implemented to ensure acceptable system dynamic behavior. Numerical results are validated with experimental measurements to investigate the significance of the PCH approach for the energy management operation in eco-tractions.

  12. Control and management of energy in a PV system equipped with batteries storage

    Directory of Open Access Journals (Sweden)

    Kamal Hirech

    2016-06-01

    Full Text Available In this paper we present a work concerning the conception, implementation and testing of a photovoltaic system that is equipped with a new concept of control and manage the energy in a PV system with a battery storage. The objective is to exploit the maximum of power using Hill climbing improved algorithm that considers optimal electrical characteristics of PV panels regardless of the system perturbation, to manage the energy between blocs of PV system in order to control the charge/discharge process and inject the energy surplus into the grid and also to estimate the state of charge with precision. Moreover, the system guarantees the acquisition and presentation of results on computer, supervision and so on. The results obtained show the robustness of the PV system, good control and protection of batteries under the maximum of energy provided by the PV panels. The state of charge estimation is evaluated by using measured parameters in real time; it shows an improvement of around 5% compared to the conventional technique.

  13. Energy Conservation in an Office Building Using an Enhanced Blind System Control

    Directory of Open Access Journals (Sweden)

    Edorta Carrascal-Lekunberri

    2017-02-01

    Full Text Available The two spaces office module is usually considered as a representative case-study to analyse the energetic improvement in office buildings. In this kind of buildings, the use of a model predictive control (MPC scheme for the climate system control provides energy savings over 15% in comparison to classic control policies. This paper focuses on the influence of solar radiation on the climate control of the office module under Belgian weather conditions. Considering MPC as main climate control, it proposes a novel distributed enhanced control for the blind system (BS that takes into account part of the predictive information of the MPC. In addition to the savings that are usually achieved by MPC, it adds a potential 15% improvement in global energy use with respect to the usually proposed BS hysteresis control. Moreover, from the simulation results it can be concluded that the thermal comfort is also improved. The proposed BS scheme increases the energy use ratio between the thermally activated building system (TABS and air-handling unit (AHU; therefore increasing the use of TABS and allowing economic savings, due to the use of more cost-effective thermal equipment.

  14. A Control Strategy for Flywheel Energy Storage System for Frequency Stability Improvement in Islanded Microgrid

    Directory of Open Access Journals (Sweden)

    A. A. Khodadoost Arani

    2017-03-01

    Full Text Available The Micro-Grid (MG stability is a significant issue that must be maintained in all operational modes. Usually, two control strategies can be applied to MG; V/f control and PQ control strategies. MGs with V/f control strategy should have some Distributed Generators (DGs which have fast responses versus load changes. The Flywheel Energy Storage System (FESS has this characteristic. The FESS, which converts the mechanical energy to electrical form, can generate electrical power or absorb the additional power in power systems or MGs. In this paper, the FESS structure modeled in detail and two control strategies (V/f and PQ control are applied for this application. In addition, in order to improve the MG frequency and voltage stability, two complementary controllers are proposed for the V/f control strategy; conventional PI and Fuzzy Controllers. A typical low voltage network, including FESS is simulated for four distinct scenarios in the MATLAB/ Simulink environment. It is shown that fuzzy controller has better performance than conventional PI controller in islanded microgrid.

  15. Distributed Generation Integration in the Electric Grid: Energy Storage System for Frequency Control

    Directory of Open Access Journals (Sweden)

    Maurizio Delfanti

    2014-01-01

    Full Text Available During the last few years generation from renewable energy sources (RESs has grown considerably in European electrical networks. Transmission system operators are greatly concerned about the impact of RESs on the operational security and efficiency of their networks and more in general of the ENTSO-E interconnected system. Grid codes are to be revised in order to harmonise the rules regarding the connection of RES power plants. A main issue concerns frequency control: frequency is greatly affected by RESs intermittency and its deviations must be limited as much as possible in order to guarantee a suitable level of power quality. To improve frequency stability, in the future, Grid codes could extend frequency control requirements also to RES units, whereas today they are applied only to conventional power plants. Energy storage systems can be a possible solution to increase the flexibility and performance of RES power plants: they allow generators to modulate their power injections without wasting renewable energy. In this paper, the authors studied the suitability of extending frequency control to RES units integrating them with energy storage systems. In particular, the paper focuses on the impact of frequency control on the storage lifetime by analysing the power charge/discharge in response to real frequency oscillations.

  16. Design of Energy Storage Control Strategy to Improve the PV System Power Quality

    DEFF Research Database (Denmark)

    Lei, Mingyu; Yang, Zilong; Wang, Yibo

    2016-01-01

    Random fluctuation of PV power is becoming a more and more serious problem affecting the power quality and stability of grid as the PV penetration keeps increasing recent years. Aiming at this problem, this paper proposed a control strategy of energy storage system based on Model Predictive Contr...

  17. Control of a battery energy storage system connected to a low voltage grid

    NARCIS (Netherlands)

    van Dun, J.J.C.M.; de Groot, Robert; Morren, Johan; Slootweg, Han

    2015-01-01

    This paper describes the development of a control algorithm for a battery energy storage system, which is connected to a residential low voltage grid. By predicting future load demand and photovoltaic production within the neighbourhood concerned, flattening of the aggregated neighbourhood

  18. A Control Algorithm for Electric Vehicle Fast Charging Stations Equipped with Flywheel Energy Storage Systems

    DEFF Research Database (Denmark)

    Sun, Bo; Dragicevic, Tomislav; Freijedo Fernandez, Francisco Daniel

    2016-01-01

    This paper proposes a control strategy for plugin electric vehicle (PEV) fast charging station (FCS) equipped with a flywheel energy storage system (FESS). The main role of the FESS is not to compromise the predefined charging profile of PEV battery during the provision of a hysteresis-type active...

  19. Two-Level Control for Fast Electrical Vehicle Charging Stations with Multi Flywheel Energy Storage System

    DEFF Research Database (Denmark)

    SUN, BO; Dragicevic, Tomislav; Vasquez, Juan Carlos

    2015-01-01

    This paper applies a hierarchical control for a fast charging station (FCS) composed of paralleled PWM rectifier and dedicated paralleled multiple flywheel energy storage systems (FESSs), in order to mitigate peak power shock on grid caused by sudden connection of electrical vehicle (EV) chargers...

  20. Potential energy savings using dynamically optimizing control in refrigeration systems under daily variations in ambient temperature

    DEFF Research Database (Denmark)

    Larsen, Lars Finn Sloth; Thybo, Claus; Wisniewski, Rafal

    2007-01-01

    The objective of this study is to investigate the energy saving potential for refrigeration systems by refrigeration more at the colder night time than at the warmer day time. The potential is evaluated using an optimal control policy and illustrated on a simulation example. The results show...

  1. Design and Analysis of the Power Control System of the Fast Zero Energy Reactor FR-0

    Energy Technology Data Exchange (ETDEWEB)

    Schuh, N J.H.

    1966-12-15

    This report describes the power control by means of the fine-control rod and the design of the control system of the fast zero energy reactor FR-0 located in Studsvik, Sweden. System requirements and some operational conditions were used as design criteria. Manual and automatic control is possible. Variable electronic end-stops for the control rod have been designed, because of the special construction of the reactor and control rod. Noise in the control system caused by the reactor, detector and electronics caused disturbances of the control system at the lower power levels. The noise power-spectrum was measured. Statistical design methods, using the measured noise power spectrum, were used to design filters, which will reduce the influence of the noise at the lower power levels. Root Loci sketches and Bode diagrams were used for stability analyses. The system was simulated on an analogue computer, taking into account even nonlinearities of the control system and noise. Typical cases of reactor operation were simulated and stability analysis performed.

  2. Design and Analysis of the Power Control System of the Fast Zero Energy Reactor FR-0

    International Nuclear Information System (INIS)

    Schuh, N.J.H.

    1966-12-01

    This report describes the power control by means of the fine-control rod and the design of the control system of the fast zero energy reactor FR-0 located in Studsvik, Sweden. System requirements and some operational conditions were used as design criteria. Manual and automatic control is possible. Variable electronic end-stops for the control rod have been designed, because of the special construction of the reactor and control rod. Noise in the control system caused by the reactor, detector and electronics caused disturbances of the control system at the lower power levels. The noise power-spectrum was measured. Statistical design methods, using the measured noise power spectrum, were used to design filters, which will reduce the influence of the noise at the lower power levels. Root Loci sketches and Bode diagrams were used for stability analyses. The system was simulated on an analogue computer, taking into account even nonlinearities of the control system and noise. Typical cases of reactor operation were simulated and stability analysis performed

  3. Variable flow controls of closed system pumps for energy savings in maritime power systems

    DEFF Research Database (Denmark)

    Su, Chun-Lien; Liao, Chi-Hsiang; Chou, Tso-Chu

    2016-01-01

    and field tests of a practical auxiliary boiler feed water management system on a commercial vessel. It is proved that the proposed method can maintain constant water pressure for closed system pumps and provide an efficient way to measure energy savings and maintenance benefits. The results serve......Pumps are extensively used in maritime industries as marine vessels utilize a wide range of pumps and pumping techniques to transfer and distribute all types of air and fluids. The electrical energy consumed by the various motors accounts for about 70% of a vessel’s total power consumption......, and this presents a problem in unique marine environments. Such situations are especially conducive to energy-saving strategies using variable frequency drives (VFDs) in centrifugal load service. This paper presents the design and results of applying variable frequency constant pressure technology in closed system...

  4. Multi-sources model and control algorithm of an energy management system for light electric vehicles

    International Nuclear Information System (INIS)

    Hannan, M.A.; Azidin, F.A.; Mohamed, A.

    2012-01-01

    Highlights: ► An energy management system (EMS) is developed for a scooter under normal and heavy power load conditions. ► The battery, FC, SC, EMS, DC machine and vehicle dynamics are modeled and designed for the system. ► State-based logic control algorithms provide an efficient and feasible multi-source EMS for light electric vehicles. ► Vehicle’s speed and power are closely matched with the ECE-47 driving cycle under normal and heavy load conditions. ► Sources of energy changeover occurred at 50% of the battery state of charge level in heavy load conditions. - Abstract: This paper presents the multi-sources energy models and ruled based feedback control algorithm of an energy management system (EMS) for light electric vehicle (LEV), i.e., scooters. The multiple sources of energy, such as a battery, fuel cell (FC) and super-capacitor (SC), EMS and power controller, DC machine and vehicle dynamics are designed and modeled using MATLAB/SIMULINK. The developed control strategies continuously support the EMS of the multiple sources of energy for a scooter under normal and heavy power load conditions. The performance of the proposed system is analyzed and compared with that of the ECE-47 test drive cycle in terms of vehicle speed and load power. The results show that the designed vehicle’s speed and load power closely match those of the ECE-47 test driving cycle under normal and heavy load conditions. This study’s results suggest that the proposed control algorithm provides an efficient and feasible EMS for LEV.

  5. Optimal Active Power Control of A Wind Farm Equipped with Energy Storage System based on Distributed Model Predictive Control

    DEFF Research Database (Denmark)

    Zhao, Haoran; Wu, Qiuwei; Guo, Qinglai

    2016-01-01

    This paper presents the Distributed Model Predictive Control (D-MPC) of a wind farm equipped with fast and short-term Energy Storage System (ESS) for optimal active power control using the fast gradient method via dual decomposition. The primary objective of the D-MPC control of the wind farm...... is power reference tracking from system operators. Besides, by optimal distribution of the power references to individual wind turbines and the ESS unit, the wind turbine mechanical loads are alleviated. With the fast gradient method, the convergence rate of the DMPC is significantly improved which leads...

  6. Adaptive automatic generation control with superconducting magnetic energy storage in power systems

    International Nuclear Information System (INIS)

    Tripathy, S.C.; Balasubramanian, R.; Nair, P.S.C.

    1992-01-01

    An improved automatic generation control (AGC) employing self-tuning adaptive control for both main AGC loop and superconducting magnetic energy storage (SMES) is presented in this paper. Computer simulations on a two-area interconnected power system show that the proposed adaptive control scheme is very effective in damping out oscillations caused by load disturbances and its performance is quite insensitive to controller gain parameter changes of SMES. A comprehensive comparative performance evaluation of control schemes using adaptive and non-adaptive controllers in the main AGC and in the SMES control loops is presented. The improvement in performance brought in by the adaptive scheme is particularly pronounced for load changes of random magnitude and duration. The proposed controller can be easily implemented using microprocessors

  7. A Model Predictive Control-Based Power Converter System for Oscillating Water Column Wave Energy Converters

    Directory of Open Access Journals (Sweden)

    Gimara Rajapakse

    2017-10-01

    Full Text Available Despite the predictability and availability at large scale, wave energy conversion (WEC has still not become a mainstream renewable energy technology. One of the main reasons is the large variations in the extracted power which could lead to instabilities in the power grid. In addition, maintaining the speed of the turbine within optimal range under changing wave conditions is another control challenge, especially in oscillating water column (OWC type WEC systems. As a solution to the first issue, this paper proposes the direct connection of a battery bank into the dc-link of the back-to-back power converter system, thereby smoothening the power delivered to the grid. For the second issue, model predictive controllers (MPCs are developed for the rectifier and the inverter of the back-to-back converter system aiming to maintain the turbine speed within its optimum range. In addition, MPC controllers are designed to control the battery current as well, in both charging and discharging conditions. Operations of the proposed battery direct integration scheme and control solutions are verified through computer simulations. Simulation results show that the proposed integrated energy storage and control solutions are capable of delivering smooth power to the grid while maintaining the turbine speed within its optimum range under varying wave conditions.

  8. WAMS Based Damping Control of Inter-area Oscillations Employing Energy Storage System

    Directory of Open Access Journals (Sweden)

    MA, J.

    2012-05-01

    Full Text Available This paper presents a systematic design procedure for a wide-area damping controller (WADC employing Energy Storage Systems (ESSs. The WADC is aimed at enhancing the damping of multiple inter-area modes in a large scale power system. Firstly, geometric measures of controllability and obsevability are used to select the control locations for ESSs and most effective stabilizing signals, respectively. Then, the WADC coordinates these signals to achieve multiple-input-multiple-output (MIMO controllers with the least Frobenius norm feedback gain matrix. The simulation results of frequency and time domains verify the effectiveness of the wide-area damping controller for various operating conditions. Furthermore, the robustness of the wide-area damping controller is also tested with respect to time delay and uncertainty of models.

  9. A new energy-efficient control approach for astronomical telescope drive system

    Science.gov (United States)

    Zhou, W.; Wang, Y.

    2012-12-01

    Drive control makes the astronomical telescope accurately tracking celestial bodies in spite of external and internal disturbances, which is a key technique to the performance of telescopes. In this paper, we propose a nonlinear ad, aptive observer based on power reversible approach for high precision telescope position tracking. The nonlinear adaptive observer automatically estimates the disturbances in drive system, and the observed value is applied to compensate for the real disturbances. With greatly reduced disturbances, the control precision can be evidently improved. In conventional drive control, the brake device is often used to slow down the reaction wheel and may waste enormous energy. To avoid those disadvantages, an H-bridge is put forward for wheel speed regulation. Such H-bridge has four independent sections, and each section mainly consists of a power electronic switch and an anti-parallel diode. During the period of the mount slowing down, the armature current of drive motor goes through the two path-wise diodes to charge the battery. Thus, energy waste is avoided. Based on the disturbance compensation, an optimal controller is designed to minimize an evaluation function which is made up of a weighted sum of position errors and energy consumption.The outputs of the controller are applied to control the H-bridge. Simulations are performed in MATLAB language. The results show that high precision control can be obtained by the proposed approach. And the energy consumption will be remarkably reduced.

  10. Hybrid Intelligent Control Method to Improve the Frequency Support Capability of Wind Energy Conversion Systems

    Directory of Open Access Journals (Sweden)

    Shin Young Heo

    2015-10-01

    Full Text Available This paper presents a hybrid intelligent control method that enables frequency support control for permanent magnet synchronous generators (PMSGs wind turbines. The proposed method for a wind energy conversion system (WECS is designed to have PMSG modeling and full-scale back-to-back insulated-gate bipolar transistor (IGBT converters comprising the machine and grid side. The controller of the machine side converter (MSC and the grid side converter (GSC are designed to achieve maximum power point tracking (MPPT based on an improved hill climb searching (IHCS control algorithm and de-loaded (DL operation to obtain a power margin. Along with this comprehensive control of maximum power tracking mode based on the IHCS, a method for kinetic energy (KE discharge control of the supporting primary frequency control scheme with DL operation is developed to regulate the short-term frequency response and maintain reliable operation of the power system. The effectiveness of the hybrid intelligent control method is verified by a numerical simulation in PSCAD/EMTDC. Simulation results show that the proposed approach can improve the frequency regulation capability in the power system.

  11. Monitoring and controlling energy consumption as a basis for energy management systems in hotels

    International Nuclear Information System (INIS)

    Pino, C.

    2016-01-01

    Following the sharp increases in the price of energy over the last six years and the increasingly widespread incorporation of installations that offer added value to the establishment but which increase its energy expenditure (spas, swimming pools, gymnasiums, etc.), the hotel sector today is aware of the significance of energy as part of its operating costs. Proof of this is that fact that a large proportion of hotels have undertaken, or are considering carrying out, some form of measure to improve energy efficiency. (Author)

  12. Flexible Mode Control of Grid Connected Wind Energy Conversion System Using Wavelet

    OpenAIRE

    Jain, Bhavna; Singh, Sameer; Jain, Shailendra; Nema, R. K.

    2015-01-01

    Small wind turbine systems offer services to critical loads during grid faults and also connected back to grid in normal condition. The connection of a wind energy conversion system to the grid requires a robust phase locked loop (PLL) and continuous monitoring of the grid conditions such as overvoltage, undervoltage, overfrequency, underfrequency, and grid outages. This paper describes a flexible control operation to operate a small wind turbine in both stand-alone mode via planned islanding...

  13. Design and experiment of controlled bistable vortex induced vibration energy harvesting systems operating in chaotic regions

    Science.gov (United States)

    Huynh, B. H.; Tjahjowidodo, T.; Zhong, Z.-W.; Wang, Y.; Srikanth, N.

    2018-01-01

    Vortex induced vibration based energy harvesting systems have gained interests in these recent years due to its potential as a low water current energy source. However, the effectiveness of the system is limited only at a certain water current due to the resonance principle that governs the concept. In order to extend the working range, a bistable spring to support the structure is introduced on the system. The improvement on the performance is essentially dependent on the bistable gap as one of the main parameters of the nonlinear spring. A sufficiently large bistable gap will result in a significant performance improvement. Unfortunately, a large bistable gap might also increase a chance of chaotic responses, which in turn will result in diminutive harvested power. To mitigate the problem, an appropriate control structure is required to stabilize the chaotic vibrations of a VIV energy converter with the bistable supporting structure. Based on the nature of the double-well potential energy in a bistable spring, the ideal control structure will attempt to drive the responses to inter-well periodic vibrations in order to maximize the harvested power. In this paper, the OGY control algorithm is designed and implemented to the system. The control strategy is selected since it requires only a small perturbation in a structural parameter to execute the control effort, thus, minimum power is needed to drive the control input. Facilitated by a wake oscillator model, the bistable VIV system is modelled as a 4-dimensional autonomous continuous-time dynamical system. To implement the controller strategy, the system is discretized at a period estimated from the subspace hyperplane intersecting to the chaotic trajectory, whereas the fixed points that correspond to the desired periodic orbits are estimated by the recurrence method. Simultaneously, the Jacobian and sensitivity matrices are estimated by the least square regression method. Based on the defined fixed point and the

  14. Frequency Transient Suppression in Hybrid Electric Ship Power Systems: A Model Predictive Control Strategy for Converter Control with Energy Storage

    Directory of Open Access Journals (Sweden)

    Viknash Shagar

    2018-03-01

    Full Text Available This paper aims to understand how the common phenomenon of fluctuations in propulsion and service load demand contribute to frequency transients in hybrid electric ship power systems. These fluctuations arise mainly due to changes in sea conditions resulting in significant variations in the propulsion load demand of ships. This leads to poor power quality for the power system that can potentially cause hazardous conditions such as blackout on board the ship. Effects of these fluctuations are analysed using a hybrid electric ship power system model and a proposed Model Predictive Control (MPC strategy to prevent propagation of transients from the propellers into the shipboard power system. A battery energy storage system, which is directly connected to the DC-link of the frequency converter, is used as the smoothing element. Case studies that involve propulsion and service load changes have been carried out to investigate the efficacy of the proposed solution. Simulation results show that the proposed solution with energy storage and MPC is able to contain frequency transients in the shipboard power system within the permissible levels stipulated by the relevant power quality standards. These findings will help ship builders and operators to consider using battery energy storage systems controlled by advanced control techniques such as MPC to improve the power quality on board ships.

  15. Performance improvement of a slip energy recovery drive system by a voltage-controlled technique

    Energy Technology Data Exchange (ETDEWEB)

    Tunyasrirut, Satean [Department of Instrumentation Engineering, Faculty of Engineering, Pathumwan Institute of Technology, 833 Rama1 Road, Pathumwan, Bangkok 10330 (Thailand); Kinnares, Vijit [Department of Electrical Engineering, Faculty of Engineering, King Mongkut' s Institute of Technology Ladkrabang, Bangkok 10520 (Thailand); Ngamwiwit, Jongkol [Department of Control Engineering, Faculty of Engineering, King Mongkut' s Institute of Technology Ladkrabang, Bangkok 10520 (Thailand)

    2010-10-15

    This paper introduces the performance improvement of a slip energy recovery drive system for the speed control of a wound rotor induction motor by a voltage-controlled technique. The slip energy occurred in the rotor circuit is transferred back to ac mains supply through a reactor instead of a step up transformer. The objective of the voltage-controlled technique is to increase power factor of the system and to reduce low order harmonics of the input line current. The drive system is designed and implemented using a voltage source inverter in conjunction with a boost chopper for DC link voltage, instead of a conventional drive using a 6 pulse converter or a Scherbius system. The slip power is recovered by the help of a voltage source inverter (VSI) based on a space vector pulse width modulation (SVPWM) technique. In order to keep the speed of the wound rotor induction motor constant over a certain range of operating conditions, the servo state feedback controller designed by a linear quadratic regulator (LQR) is also introduced in this paper. The overall control system is implemented on DSP, DS1104'TMS320F240 controller board. The performance improvement of the proposed system is tested in comparison with the conventional Scherbius system and the modified conventional Scherbius system by a 12 pulse converter in conjunction with a chopper at steady state and at dynamic conditions. A 220 W wound motor is employed for testing. It is found that the motor speed can be controlled to be constant in the operating range of 450-1200 rpm at no load and full load. It is also found that the efficiency of the proposed system is remarkably increased since the harmonics of the input ac line current is reduced while the ac line input power factor is increased. (author)

  16. Min-max control of fuel-cell-car-based smart energy systems

    OpenAIRE

    Alavi, F.; van de Wouw, N.; De Schutter, B.H.K.; Rantzer, Anders; Bagterp Jørgensen, John; Stoustrup, Jakob

    2016-01-01

    Recently, the idea of using fuel cell vehicles as the future way of producing electricity has emerged. A fuel cell car has all the necessary devices on board to convert the chemical energy of hydrogen into electricity. This paper considers a scenario where a parking lot for fuel cell cars acts as a virtual power plant. In order to describe the system behavior from the energy point of view, a hybrid (mixed logical dynamical) model is constructed. With this model, a control system is designed t...

  17. Energy efficient model based algorithm for control of building HVAC systems.

    Science.gov (United States)

    Kirubakaran, V; Sahu, Chinmay; Radhakrishnan, T K; Sivakumaran, N

    2015-11-01

    Energy efficient designs are receiving increasing attention in various fields of engineering. Heating ventilation and air conditioning (HVAC) control system designs involve improved energy usage with an acceptable relaxation in thermal comfort. In this paper, real time data from a building HVAC system provided by BuildingLAB is considered. A resistor-capacitor (RC) framework for representing thermal dynamics of the building is estimated using particle swarm optimization (PSO) algorithm. With objective costs as thermal comfort (deviation of room temperature from required temperature) and energy measure (Ecm) explicit MPC design for this building model is executed based on its state space representation of the supply water temperature (input)/room temperature (output) dynamics. The controllers are subjected to servo tracking and external disturbance (ambient temperature) is provided from the real time data during closed loop control. The control strategies are ported on a PIC32mx series microcontroller platform. The building model is implemented in MATLAB and hardware in loop (HIL) testing of the strategies is executed over a USB port. Results indicate that compared to traditional proportional integral (PI) controllers, the explicit MPC's improve both energy efficiency and thermal comfort significantly. Copyright © 2015 Elsevier Inc. All rights reserved.

  18. Stand-alone power systems for the future: Optimal design, operation and control of solar-hydrogen energy systems

    Energy Technology Data Exchange (ETDEWEB)

    Ulleberg, Oeystein

    1999-12-31

    This thesis gives a systematic review of the fundamentals of energy systems, the governing physical and chemical laws related to energy, inherent characteristics of energy system, and the availability of the earth`s energy. It shows clearly why solar-hydrogen systems are one of the most viable options for the future. The main subject discussed is the modelling of SAPS (Stand-Alone Power Systems), with focus on photovoltaic-hydrogen energy systems. Simulation models for a transient simulation program are developed for PV-H{sub 2} components, including models for photovoltaics, water electrolysis, hydrogen storage, fuel cells, and secondary batteries. A PV-H{sub 2} demonstration plant in Juelich, Germany, is studied as a reference plant and the models validated against data from this plant. Most of the models developed were found to be sufficiently accurate to perform short-term system simulations, while all were more than accurate enough to perform long-term simulations. Finally, the verified simulation models are used to find the optimal operation and control strategies of an existing PV-H{sub 2} system. The main conclusion is that the simulation methods can be successfully used to find optimal operation and control strategies for a system with fixed design, and similar methods could be used to find alternative system designs. 148 refs., 78 figs., 31 tabs.

  19. Stand-alone power systems for the future: Optimal design, operation and control of solar-hydrogen energy systems

    Energy Technology Data Exchange (ETDEWEB)

    Ulleberg, Oeystein

    1998-12-31

    This thesis gives a systematic review of the fundamentals of energy systems, the governing physical and chemical laws related to energy, inherent characteristics of energy system, and the availability of the earth`s energy. It shows clearly why solar-hydrogen systems are one of the most viable options for the future. The main subject discussed is the modelling of SAPS (Stand-Alone Power Systems), with focus on photovoltaic-hydrogen energy systems. Simulation models for a transient simulation program are developed for PV-H{sub 2} components, including models for photovoltaics, water electrolysis, hydrogen storage, fuel cells, and secondary batteries. A PV-H{sub 2} demonstration plant in Juelich, Germany, is studied as a reference plant and the models validated against data from this plant. Most of the models developed were found to be sufficiently accurate to perform short-term system simulations, while all were more than accurate enough to perform long-term simulations. Finally, the verified simulation models are used to find the optimal operation and control strategies of an existing PV-H{sub 2} system. The main conclusion is that the simulation methods can be successfully used to find optimal operation and control strategies for a system with fixed design, and similar methods could be used to find alternative system designs. 148 refs., 78 figs., 31 tabs.

  20. Load Frequency Control of Two-Area Network using Renewable Energy Resources and Battery Energy Storage System

    Directory of Open Access Journals (Sweden)

    Norhafiz Bin SALIM

    2017-06-01

    Full Text Available In an interconnected system, the frequency and tie-line power interchange are very susceptible with the diversification of power load demand. Literally, in a multi-area power system, the load frequency control (LFC is substantially aimed to minimise the deviations of these parameters relatively. Knowingly, the power production from renewable energy resources could offer promising solutions despite their intermittency (i.e. photovoltaic/wind generation, hence in this context, a battery energy storage system (BESS is proposed to delineate dynamic response along with grid—connection. This study has proposed LFC with BESS control method to suppress frequency deviations for a power system and being compared with photovoltaic (PV approach. The effectiveness was verified using newly developed AGC30 model of Japanese Power System and was modelled using MATLAB Simulink. Furthermore, an analysis of the tie-line power oscillations also are carried out and comparison analysis demonstrates further the reliability of the proposed model and control methods.

  1. Development and Application of a ZigBee-Based Building Energy Monitoring and Control System

    Directory of Open Access Journals (Sweden)

    Changhai Peng

    2014-01-01

    Full Text Available Increasing in energy consumption, particularly with the ever-increasing growth and development of urban systems, has become a major concern in most countries. In this paper, the authors propose a cost-effective ZigBee-based building energy monitoring and control system (ZBEMCS, which is composed of a gateway, a base station, and sensors. Specifically, a new hardware platform for power sensor nodes is developed to perform both local/remote power parameter measurement and power on/off switching for electric appliances. The experimental results show that the ZBEMCS can easily monitor energy usage with a high level of accuracy. Two typical applications of ZBEMCS such as subentry metering and household metering of building energy are presented. The former includes lighting socket electricity, HVAC electricity, power electricity and special electricity. The latter includes household metering according to the campus’s main function zone and each college or department. Therefore, this system can be used for energy consumption monitoring, long-term energy conservation planning, and the development of automated energy conservation for building applications.

  2. A current controlled matrix converter for wind energy conversion systems based on permanent magnet synchronous generator

    Directory of Open Access Journals (Sweden)

    Naggar H. Saad

    2016-05-01

    Full Text Available The main challenges of wind energy conversion systems (WECS are to maximize the energy capture from the wind and injecting reactive power during the fault. This paper presents a current controlled matrix converter to interface Permanent Magnet Synchronous Generators (PMSG based WECS with the grid. To achieve fast dynamic response with reduced current ripples, a hysteresis current control is utilized. The proposed control system decouples the active and reactive components of the PMSG current to extract the maximum power from the wind at a given wind velocity and to inject reactive power to the grid. Reactive power injection during the fault satisfying the grid-codes requirement. The proposed WECS has been modeled and simulated using PSCAD/EMTDC software package.

  3. Discomfort glare with complex fenestration systems and the impact on energy use when using daylighting control

    Energy Technology Data Exchange (ETDEWEB)

    Hoffmann, Sabine; McNeil, Andrew; Lee, Eleanor S.; Kalyanam, Raghuram

    2015-11-03

    Glare is a frequent issue in highly glazed buildings. A modelling approach is presented that uses discomfort glare probability and discomfort glare index as metrics to determine occupants’ behaviour. A glare control algorithm that actuated an interior shade for glare protection based on the predicted perception was implemented in a building simulation program. A reference case with a state-of-the-art base glazing was compared to the same glazing but with five different complex fenestration systems, i.e., exterior shades. The windows with exterior shades showed significant variations in glare frequencies. Energy use intensity in a prototypical office building with daylighting controls was greatly influenced for the systems with frequent glare occurrence. While the base glazing could benefit from glare control, some of the exterior shades showed significantly greater energy use when discomfort glare-based operation of interior shades was considered.

  4. Development of distributed measurement and control systems for application in electrical energy systems

    Directory of Open Access Journals (Sweden)

    Gajić Tomislav

    2013-01-01

    Full Text Available In this paper LPC1766 microcontroller based network capable application processor (NCAP system, is described. This system is intended to be used in modern distributed control and monitoring systems for application in power plants and industry, as well as in modern electricity distribution networks. In order to do that it is necessary to analyze different aspects of the system, like signal processing part or communication requirements. The chosen microcontroller has enough resources to satisfy requirements of an transducer interface module (TIM. Beside the realization of NCAp and TIM controllers it is necessary to develop the necessary measurement modules, in order to realize measurement-control systems. The developed layout could be connected to actuators to the local area network (LAN, as well. If the local LAN is connected to the internet it is possible to monitor and configure measurement modules form the remote site. Having in mind the growing complexity in control systems, it has been a real challenge to detect a diagnose problems in today's large scale distributed systems. Implementation of the proposed module could potentially reduce the time necessary to extract necessary information from the abundant quantity of information that are usually provided by the complex distributed systems.

  5. Modular Hybrid Energy Concept Employing a Novel Control Structure Based on a Simple Analog System

    Directory of Open Access Journals (Sweden)

    PETREUS, D.

    2016-05-01

    Full Text Available This paper proposes a novel control topology which enables the setup of a low cost analog system leading to the implementation of a modular energy conversion system. The modular concept is based on hybrid renewable energy (solar and wind and uses high voltage inverters already available on the market. An important feature of the proposed topology is a permanently active current loop, which assures short circuit protection and simplifies the control loops compensation. The innovative analogue solution of the control structure is based on a dedicated integrated circuit (IC for power factor correction (PFC circuits, used in a new configuration, to assure an efficient inverter start-up. The energy conversion system (control structure and maximum power point tracking algorithm is simulated using a new macromodel-based concept, which reduces the usual computational burden of the simulator and achieves high processing speed. The proposed novel system is presented in this article from concept, through the design and implementation stages, is verified through simulation and is validated by experimental results.

  6. Direct Load Control (DLC) Considering Nodal Interrupted Energy Assessment Rate (NIEAR) in Restructured Power Systems

    DEFF Research Database (Denmark)

    Wu, Qiuwei; Wang, Peng; Goel, Lalit

    2010-01-01

    is used as the bids from the ACL customers, is utilized to determine the direct monetary compensation to the ACL customers. The proposed scheme was investigated for the PoolCo electricity market. The optimal DLC scheme is determined based on the minimum system operating cost which is comprised......A direct load control (DLC) scheme of air conditioning loads (ACL) considering direct monetary compensation to ACL customers for the service interruption caused by the DLC program is proposed in this paper for restructured power systems. The nodal interrupted energy assessment rate (NIEAR), which...... of the system energy cost, the system spinning reserve cost and the compensation cost to the ACL customers. Dynamic programming (DP) was used to obtain the optimal DLC scheme. The IEEE reliability test system (RTS) was studied to illustrate the proposed DLC scheme....

  7. A Predictive Power Control Strategy for DFIGs Based on a Wind Energy Converter System

    Directory of Open Access Journals (Sweden)

    Xiaoliang Yang

    2017-07-01

    Full Text Available A feasible control strategy is proposed to control a doubly fed induction generator based on the wind energy converter system (DFIG-WECS. The main aim is to enhance the steady state and dynamic performance under the condition of the parameter perturbations and external disturbances and to satisfy the stator power response of the system. Within the proposed control method, the control scheme for the rotor side converter (RSC is developed on the model predictive control. Firstly, the self-adaptive reference trajectory is established from the deduced discrete state-space equation of the generator. Then, the rotor voltage is calculated by minimizing the global performance index under the current prediction steps at the sampling instant. Through the control scheme for the grid side converter (GSC and wind turbine, we have re-applied the conventional control. The effectiveness of the proposed control strategy is verified via time domain simulation of a 150 kW-575 V DFIG-WECS using Matlab/Simulink. The simulation result shows that the control of the DFIG with the proposed control method can enhance the steady and dynamic response capability better than the conventional ones when the system faces errors due to the parameter perturbations, external disturbances and the rotor speed.

  8. Research on Improved VSG Control Algorithm Based on Capacity-Limited Energy Storage System

    Directory of Open Access Journals (Sweden)

    Yanfeng Ma

    2018-03-01

    Full Text Available A large scale of renewable energy employing grid connected electronic inverters fail to contribute inertia or damping to power systems, and, therefore, may bring negative effects to the stability of power system. As a solution, an advanced Virtual Synchronous Generator (VSG control technology based on Hamilton approach is introduced in this paper firstly to support the frequency and enhance the suitability and robustness of the system. The charge and discharge process of power storage devices forms the virtual inertia and damping of VSG, and, therefore, limits on storage capacity may change the coefficients of VSG. To provide a method in keeping system output in an acceptable level with the capacity restriction in a transient period, an energy control algorithm is designed for VSG adaptive control. Finally, simulations are conducted in DIgSILENT to demonstrate the correctness of the algorithm. The demonstration shows: (1 the proposed control model aims at better system robustness and stability; and (2 the model performs in the environment closer to practical engineering by fitting the operation state of storage system.

  9. Model predictive control-based efficient energy recovery control strategy for regenerative braking system of hybrid electric bus

    International Nuclear Information System (INIS)

    Li, Liang; Zhang, Yuanbo; Yang, Chao; Yan, Bingjie; Marina Martinez, C.

    2016-01-01

    Highlights: • A 7-degree-of-freedom model of hybrid electric vehicle with regenerative braking system is built. • A modified nonlinear model predictive control strategy is developed. • The particle swarm optimization algorithm is employed to solve the optimization problem. • The proposed control strategy is verified by simulation and hardware-in-loop tests. • Test results verify the effectiveness of the proposed control strategy. - Abstract: As one of the main working modes, the energy recovered with regenerative braking system provides an effective approach so as to greatly improve fuel economy of hybrid electric bus. However, it is still a challenging issue to ensure braking stability while maximizing braking energy recovery. To solve this problem, an efficient energy recovery control strategy is proposed based on the modified nonlinear model predictive control method. Firstly, combined with the characteristics of the compound braking process of single-shaft parallel hybrid electric bus, a 7 degrees of freedom model of the vehicle longitudinal dynamics is built. Secondly, considering nonlinear characteristic of the vehicle model and the efficiency of regenerative braking system, the particle swarm optimization algorithm within the modified nonlinear model predictive control is adopted to optimize the torque distribution between regenerative braking system and pneumatic braking system at the wheels. So as to reduce the computational time of modified nonlinear model predictive control, a nearest point method is employed during the braking process. Finally, the simulation and hardware-in-loop test are carried out on road conditions with different tire–road adhesion coefficients, and the proposed control strategy is verified by comparing it with the conventional control method employed in the baseline vehicle controller. The simulation and hardware-in-loop test results show that the proposed strategy can ensure vehicle safety during emergency braking

  10. Power converter topologies for wind energy conversion systems: Integrated modeling, control strategy and performance simulation

    Energy Technology Data Exchange (ETDEWEB)

    Melicio, R.; Catalao, J.P.S. [Department of Electromechanical Engineering, University of Beira Interior, R. Fonte do Lameiro, 6201-001 Covilha (Portugal); Mendes, V.M.F. [Department of Electrical Engineering and Automation, Instituto Superior de Engenharia de Lisboa, R. Conselheiro Emidio Navarro, 1950-062 Lisbon (Portugal)

    2010-10-15

    This paper presents new integrated model for variable-speed wind energy conversion systems, considering a more accurate dynamic of the wind turbine, rotor, generator, power converter and filter. Pulse width modulation by space vector modulation associated with sliding mode is used for controlling the power converters. Also, power factor control is introduced at the output of the power converters. Comprehensive performance simulation studies are carried out with matrix, two-level and multilevel power converter topologies in order to adequately assert the system performance. Conclusions are duly drawn. (author)

  11. A quality control method by ultrasonic vibration energy and diagnosis system at trimming process

    International Nuclear Information System (INIS)

    Suh, Chang Min; Song, Gil Ho; Pyoun, Young Shik

    2007-01-01

    In this paper, the characteristics in mechanical properties of ultrasonic cold forging treatment (UCFT) used for the trimming knife and the effects of ultrasonic vibration energy (UVE) into the trimming process on the state of the strip cutting face were studied. And a diagnosis system to quality control for trimming knife and strip cutting face was developed and installed in plant. By the plant application of UCFT, service life of knife was more increased over 100% than that of conventional knife and using the developed diagnosis system, the knife breakage and saw ear have been perfectly detected and quality control of trimming face is effectively obtained

  12. Distributed energy resources and control: A power system point of view

    Energy Technology Data Exchange (ETDEWEB)

    Gehrke, O.; Ropenus, S.; Venne, P.

    2007-05-15

    The power grid is currently facing tremendous changes in the way the energy is produced, transmitted and consumed. The increasing number of actors and the demand for more and more complex services to be provided by the grid exceed the capabilities of today's control systems. This paper gives an overview of the changes that the power system is undergoing and how these affect the aspects of communication, ancillary services, demand response, the role of the control room and market participation. (au)

  13. Air pollution control systems and technologies for waste-to-energy facilities

    International Nuclear Information System (INIS)

    Getz, N.P.; Amos, C.K. Jr.; Siebert, P.C.

    1991-01-01

    One of the primary topics of concern to those planning, developing, and operating waste-to-energy (W-T-E) [also known as municipal waste combustors (MWCs)] facilities is air emissions. This paper presents a description of the state-of-the-art air pollution control (APC) systems and technology for particulate, heavy metals, organics, and acid gases control for W-T-E facilities. Items covered include regulations, guidelines, and control techniques as applied in the W-T-E industry. Available APC technologies are viewed in detail on the basis of their potential removal efficiencies, design considerations, operations, and maintenance costs

  14. Modeling and control of distributed energy systems during transition between grid connected and standalone modes

    Science.gov (United States)

    Arafat, Md Nayeem

    Distributed generation systems (DGs) have been penetrating into our energy networks with the advancement in the renewable energy sources and energy storage elements. These systems can operate in synchronism with the utility grid referred to as the grid connected (GC) mode of operation, or work independently, referred to as the standalone (SA) mode of operation. There is a need to ensure continuous power flow during transition between GC and SA modes, referred to as the transition mode, in operating DGs. In this dissertation, efficient and effective transition control algorithms are developed for DGs operating either independently or collectively with other units. Three techniques are proposed in this dissertation to manage the proper transition operations. In the first technique, a new control algorithm is proposed for an independent DG which can operate in SA and GC modes. The proposed transition control algorithm ensures low total harmonic distortion (THD) and less voltage fluctuation during mode transitions compared to the other techniques. In the second technique, a transition control is suggested for a collective of DGs operating in a microgrid system architecture to improve the reliability of the system, reduce the cost, and provide better performance. In this technique, one of the DGs in a microgrid system, referred to as a dispatch unit , takes the additional responsibility of mode transitioning to ensure smooth transition and supply/demand balance in the microgrid. In the third technique, an alternative transition technique is proposed through hybridizing the current and droop controllers. The proposed hybrid transition control technique has higher reliability compared to the dispatch unit concept. During the GC mode, the proposed hybrid controller uses current control. During the SA mode, the hybrid controller uses droop control. During the transition mode, both of the controllers participate in formulating the inverter output voltage but with different

  15. An improved control method of battery energy storage system for hourly dispatch of photovoltaic power sources

    International Nuclear Information System (INIS)

    Daud, Muhamad Zalani; Mohamed, Azah; Hannan, M.A.

    2013-01-01

    Highlights: • Control of BES for smoothing and hourly dispatch of a PV farm output is developed. • Optimal control strategy for SOC and size of BES are evaluated using GA. • Effectiveness of the control system has been investigated for the case of Malaysia. • The proposed optimal SOC feedback controller has been found effective. • Payback calculations of BES investment is given to highlight the economic benefits. - Abstract: The effects of intermittent cloud and changes in temperature cause a randomly fluctuated output of a photovoltaic (PV) system. To mitigate the PV system impacts particularly on a weak electricity network, battery energy storage (BES) system is an effective means to smooth out the power fluctuations. Consequently, the net power injected to the electricity grid by PV and BES (PV/BES) systems can be dispatched smoothly such as on an hourly basis. This paper presents an improved control strategy for a grid-connected hybrid PV/BES systems for mitigating PV farm output power fluctuations. A feedback controller for BES state of charge is proposed, where the control parameters are optimized using genetic algorithm (GA). GA-based multi objective optimization utilizes the daily average PV farm output power profile which was obtained from simulation using the historical PV system input data of Malaysia. In this way, the optimal size for the BES is also determined to hourly dispatch a 1.2 MW PV farm. A case study for Malaysia is carried out to evaluate the effectiveness of the proposed control scheme using PSCAD/EMTDC software package. Furthermore, the validation of results of the proposed controller and BES size on the actual PV system output data are also given. Finally, a simple payback calculation is presented to study the economical aspects of the BES investment on the proposed mitigation strategy under Malaysian Feed-in Tariff program

  16. An automatic energy-saving and thermal monitoring/controlling system for a pond

    Directory of Open Access Journals (Sweden)

    Cheng Ching-Chien

    2017-01-01

    Full Text Available Because of low temperatures and oxygen in cold water, fish will die when cold currents arrive. This will cause tremendous loss of money. In order reduce the cooling of the pond, an automatic thermal detecting and cold-roofing system using a wind-proofing device, heaters, and thermal detectors is proposed. To reduce heat loss due to thermal convection above the pond surface, a motor-driven wind-proofing device automatically controlled by a PLC controller is adopted. Here, the wind-proofing device, thermal detectors, and heating system are connected to the PLC controller. The PLC will also be connected to the PC interface. The temperature thresholds used to trigger the heater and the wind proofing device can be set at the PC interface. Two options for manipulating the heating and the automatic heating can be selected. The related wind-proofing area and the number of heaters will be determined according to the current temperature. Moreover, the PLC can be wirelessly connected to the server PC in the control room. The pond keeper can monitor everything online and control the pond water's temperature. With this, the problem of fish dying in a cold wave can be solved. Consequently, to reduce the electrical exhaust when heating up the pond water, green energy, solar energy and wind energy, is used.

  17. Space and energy. [space systems for energy generation, distribution and control

    Science.gov (United States)

    Bekey, I.

    1976-01-01

    Potential contributions of space to energy-related activities are discussed. Advanced concepts presented include worldwide energy distribution to substation-sized users using low-altitude space reflectors; powering large numbers of large aircraft worldwide using laser beams reflected from space mirror complexes; providing night illumination via sunlight-reflecting space mirrors; fine-scale power programming and monitoring in transmission networks by monitoring millions of network points from space; prevention of undetected hijacking of nuclear reactor fuels by space tracking of signals from tagging transmitters on all such materials; and disposal of nuclear power plant radioactive wastes in space.

  18. Applied & Computational MathematicsChallenges for the Design and Control of Dynamic Energy Systems

    Energy Technology Data Exchange (ETDEWEB)

    Brown, D L; Burns, J A; Collis, S; Grosh, J; Jacobson, C A; Johansen, H; Mezic, I; Narayanan, S; Wetter, M

    2011-03-10

    consumption. In addition the finding was that there are tools and technologies that can be assembled and deployed in the short term - the next 3-5 years - that can be used to significantly reduce the cost and time effective delivery of moderate energy savings in the U.S. building stock. Simulation tools, which are a core strength of current DOE computational research programs, provide only a part of the answer by providing a basis for simulation enabled design. New investments will be required within a broad dynamics and control research agenda which must focus on dynamics, control, optimization and simulation of multi-scale energy systems during design and operation. U.S. investments in high performance and high productivity computing (HP2C) should be leveraged and coupled with advances in dynamics and control to impact both the existing building stock through retrofits and also new construction. The essential R&D areas requiring investment are: (1) Characterizing the Dynamics of Multi-scale Energy Systems; (2) Control and Optimization Methodologies of Multi-scale Energy Systems Under Uncertainty; and (3) Multiscale Modeling and Simulation Enabled Design and Operation. The concept of using design and control specific computational tools is a new idea for the building industry. The potential payoffs in terms of accelerated design cycle times, performance optimization and optimal supervisory control to obtain and maintain energy savings are huge. Recent advances in computational power, computer science, and mathematical algorithms offer the foundations to address the control problems presented by the complex dynamics of whole building systems. The key areas for focus and associated metrics with targets for establishing competitiveness in energy efficient building design and operation are: (1) Scalability - Current methodology and tools can provide design guidance for very low energy buildings in weeks to months; what is needed is hours to days. A 50X improvement is needed. (2

  19. NLCC controller for SEPIC-based micro-wind energy conversion system

    Science.gov (United States)

    Justin Nayagam, Brintha Jane; Sathi, Rama Reddy; Olimuthu, Divya

    2017-04-01

    The growth of the power industry is gaining greater momentum as the usage of the non-conventional energy sources that include fuel, solar, and wind energies, increases. Wind energy conversion systems (WECSs) are gaining more popularity and are expected to be able to control the power at the output. This paper describes the current control (CC), non-linear carrier charge control (NLCCC), and fuzzy logic control (FLC) applied to the single-ended primary inductor converter (SEPIC)-based WECS. The current controller has an inherent overcurrent protection with better line noise rejection. The pulses for the switch of the SEPIC are obtained by comparing the current flowing through it with the virtual current reference. FLC is also investigated for the micro-wind energy conversion system (μWECS), since it improves the damping characteristics of WECS over a wide range of operating points. This cannot attain the unity power factor rectification. In this paper, NLCCC is proposed for high-power factor rectifier-based SEPIC in continuous conduction mode (CCM) for μWECS. The proposed converter provides an output voltage with low input current ripple due to the presence of the inductor at the input side. By comparing the signal proportional to the integral of switch current with a periodic non-linear carrier wave, the duty ratio of the converter switch is determined for the NLCC controller. By selecting the shape of the periodic non-linear carrier wave the input-line current can be made to follow the input-line voltage. This work employs a parabolic carrier waveform generator. The output voltage is regulated for changes in the wind speed. The results obtained prove the effectiveness of the NLCC controller in improving the power factor.

  20. Minimum Energy Control of 2D Positive Continuous-Discrete Linear Systems

    Directory of Open Access Journals (Sweden)

    Kaczorek Tadeusz

    2014-09-01

    Full Text Available The minimum energy control problem for the 2D positive continuous-discrete linear systems is formulated and solved. Necessary and sufficient conditions for the reachability at the point of the systems are given. Sufficient conditions for the existence of solution to the problem are established. It is shown that if the system is reachable then there exists an optimal input that steers the state from zero boundary conditions to given final state and minimizing the performance index for only one step (q = 1. A procedure for solving of the problem is proposed and illustrated by a numerical example.

  1. Control strategy for a distributed DC power system with renewable energy

    Energy Technology Data Exchange (ETDEWEB)

    Kurohane, Kyohei; Uehara, Akie; Senjyu, Tomonobu; Yona, Atsushi; Urasaki, Naomitsu [University of the Ryukyus, 1 Senbaru, Nishihara-cho, Nakagami, Okinawa 903-0213 (Japan); Funabashi, Toshihisa [Meidensha Corporation, 36-2 Nihonbashi-Hakozakicho, Chuo-ku, Tokyo 103-8513 (Japan); Kim, Chul-Hwan [Sungkyunkwan University and NPT Center, Suwon City 440-746 (Korea)

    2011-01-15

    This paper deals with a DC-micro-grid with renewable energy. The proposed method is composed of a gearless wind power generation system, a battery, and DC loads in a DC distribution system. The battery helps to avoid the DC over-voltages by absorbing the power of the permanent magnet synchronous generator (PMSG) during line-fault. In addition, the control schemes presented in this paper including the maximum power point tracking (MPPT) control and a pitch angle control for the gearless wind turbine generator. By means of the proposed method, high-reliable power can be supplied to the DC distribution system during the line-fault and stable power supply from the PMSG can be achieved after line-fault clearing. The effectiveness of the proposed method is examined in a MATLAB/Simulink {sup registered} environment. (author)

  2. High-performance sensorless nonlinear power control of a flywheel energy storage system

    International Nuclear Information System (INIS)

    Amodeo, S.J.; Chiacchiarini, H.G.; Solsona, J.A.; Busada, C.A.

    2009-01-01

    The flywheel energy storage systems (FESS) can be used to store and release energy in high power pulsed systems. Based on the use of a homopolar synchronous machine in a FESS, a high performance model-based power flow control law is developed using the feedback linearization methodology. This law is based on the voltage space vector reference frame machine model. To reduce the magnetic losses, a pulse amplitude modulation driver for the armature is more adequate. The restrictions in amplitude and phase imposed by the driver are also included. A full order Luenberger observer for the torque angle and rotor speed is developed to implement a sensorless control strategy. Simulation results are presented to illustrate the performance.

  3. Controlling system for an experimental demonstration plant for energy conversion using PEMFCs

    International Nuclear Information System (INIS)

    Culcer, Mihail; Iliescu, Mariana; Stefanescu, Ioan; Raceanu, Mircea; Enache, Adrian; Patularu, Laurentiu

    2006-01-01

    Full text: In the last decades of the previous century, due to global environmental problems, energy security and supply issues, many studies were conducted to investigate the uses for hydrogen energy and facilitate its penetration as an energy carrier. Subsequently, many industries worldwide began developing and producing hydrogen, hydrogen-powered vehicles, hydrogen fuel cells, and other hydrogen-based technologies. In view of the substantial long-term public and private benefits arising from hydrogen and fuel cells, the European Union and national governments throughout Europe, including the Romanian one, are working towards developing a consistent policy framework preparing the transition to a hydrogen based economy. ICIT Rm Valcea developed a research program on energy conversion using fuel cells, a project supported by the Romanian Ministry of Education and Research within the National R and D Program. An experimental demonstration pilot plant of energy conversion using PEMFCs and hydrogen producing via steam methane reforming (SMR) was achieved in order to investigate the development of small-scale SMR technologies and to allow testing and developing of specific components. The paper deals with the dedicated controlling system that provides automated data acquisition, manual or 'on line' operational control, gas management, humidification, temperature and flow controls of the pilot plant. (authors)

  4. Fundamentals of Using Battery Energy Storage Systems to Provide Primary Control Reserves in Germany

    Directory of Open Access Journals (Sweden)

    Alexander Zeh

    2016-09-01

    Full Text Available The application of stationary battery storage systems to German electrical grids can help with various storage services. This application requires controlling the charge and discharge power of such a system. For example, photovoltaic (PV home storage, uninterruptible power supply, and storage systems for providing ancillary services such as primary control reserves (PCRs represent battery applications with positive profitability. Because PCRs are essential for stabilizing grid frequency and maintaining a robust electrical grid, German transmission system operators (TSOs released strict regulations in August 2015 for providing PCRs with battery storage systems as part of regulating the International Grid Control Cooperation (IGCC region in Europe. These regulations focused on the permissible state of charge (SoC of the battery during nominal and extreme conditions. The concomitant increased capacity demand oversizing may result in a significant profitability reduction, which can be attenuated only by using an optimal parameterization of the control algorithm for energy management of the storage systems. In this paper, the sizing optimization is achieved and a recommendation for a control algorithm that includes the appropriate parameters for the requirements in the German market is given. Furthermore, the storage cost is estimated, including battery aging simulations for different aging parameter sets to allow for a realistic profitability calculation.

  5. Data-driven modeling, control and tools for cyber-physical energy systems

    Science.gov (United States)

    Behl, Madhur

    Energy systems are experiencing a gradual but substantial change in moving away from being non-interactive and manually-controlled systems to utilizing tight integration of both cyber (computation, communications, and control) and physical representations guided by first principles based models, at all scales and levels. Furthermore, peak power reduction programs like demand response (DR) are becoming increasingly important as the volatility on the grid continues to increase due to regulation, integration of renewables and extreme weather conditions. In order to shield themselves from the risk of price volatility, end-user electricity consumers must monitor electricity prices and be flexible in the ways they choose to use electricity. This requires the use of control-oriented predictive models of an energy system's dynamics and energy consumption. Such models are needed for understanding and improving the overall energy efficiency and operating costs. However, learning dynamical models using grey/white box approaches is very cost and time prohibitive since it often requires significant financial investments in retrofitting the system with several sensors and hiring domain experts for building the model. We present the use of data-driven methods for making model capture easy and efficient for cyber-physical energy systems. We develop Model-IQ, a methodology for analysis of uncertainty propagation for building inverse modeling and controls. Given a grey-box model structure and real input data from a temporary set of sensors, Model-IQ evaluates the effect of the uncertainty propagation from sensor data to model accuracy and to closed-loop control performance. We also developed a statistical method to quantify the bias in the sensor measurement and to determine near optimal sensor placement and density for accurate data collection for model training and control. Using a real building test-bed, we show how performing an uncertainty analysis can reveal trends about

  6. Energy-Saving Tunnel Illumination System Based on LED's Intelligent Control

    International Nuclear Information System (INIS)

    Guo Shanshan; Wu Lan; Gu Hanting; Jiang Shuixiu

    2011-01-01

    At present there is a lot of electric energy wastage in tunnel illumination, whose design is based on the maximum brightness outside and the maximum vehicle speed all year round. LED's energy consumption is low, and the control of its brightness is simple and effective. It can be quickly adjusted between 0-100% of its maximum brightness, and will not affect the service life. Therefore, using LED as tunnel's illumination source, we can achieve a good energy saving effect. According to real-time data acquisition of vehicle speed, traffic flow and brightness outside the tunnel, the auto real-time control of tunnel illumination can be achieved. And the system regulated the LED luminance by means of combination of LED power module and intelligent control module. The tunnel information was detected by inspection equipments, which included luminometer, vehicle detector, and received by RTU(Remote Terminal Unit), then synchronously transmitted to PC. After data processing, RTU emitted the dimming signal to the LED driver to adjust the brightness of LED. Despite the relatively high cost of high-power LED lights, the enormous energy-saving effect and the well-behaved controllability is beyond compare to other lighting devices.

  7. A Novel Maximum Power Point Tracking Control for Permanent Magnet Direct Drive Wind Energy Conversion Systems

    Directory of Open Access Journals (Sweden)

    Wei Wang

    2012-05-01

    Full Text Available This paper proposes a novel optimal current given (OCG maximum power point tracking (MPPT control strategy based on the theory of power feedback and hill climb searching (HCS for a permanent magnet direct drive wind energy conversion system (WECS. The presented strategy not only has the advantages of not needing the wind speed and wind turbine characteristics of the traditional HCS method, but it also improves the stability and accuracy of MPPT by estimating the exact loss torque. The OCG MPPT control strategy is first carried out by simulation, then an experimental platform based on the dSPACE1103 controller is built and a 5.5 kW permanent magnet synchronous generator (PMSG is tested. Furthermore, the proposed method is compared experimentally with the traditional optimum tip speed ratio (TSR MPPT control. The experiments verify the effectiveness of the proposed OCG MPPT strategy and demonstrate its better performance than the traditional TSR MPPT control.

  8. Flexible Mode Control of Grid Connected Wind Energy Conversion System Using Wavelet

    Directory of Open Access Journals (Sweden)

    Bhavna Jain

    2015-01-01

    Full Text Available Small wind turbine systems offer services to critical loads during grid faults and also connected back to grid in normal condition. The connection of a wind energy conversion system to the grid requires a robust phase locked loop (PLL and continuous monitoring of the grid conditions such as overvoltage, undervoltage, overfrequency, underfrequency, and grid outages. This paper describes a flexible control operation to operate a small wind turbine in both stand-alone mode via planned islanding and grid connected mode as well. In particular, a proper monitoring and control algorithm is required for transition between the modes. A wavelet based energy function is used for detection of grid disturbances as well as recovery of grid so that transition between the modes is made. To obtain good power quality LCL filter is used to reduce ripples. PLL is used for synchronization whenever mode changes from stand-alone to grid connected. Simulation results from a 10 kW wind energy conversion system are included to show the usefulness of the proposed methods. The control method is tested by generated gate pulses for single phase bridge inverter using field programmable gate array (FPGA.

  9. Engineering Support for Handling Controller Conflicts in Energy Storage Systems Applications

    Directory of Open Access Journals (Sweden)

    Claudia Zanabria

    2017-10-01

    Full Text Available Energy storage systems will play a major role in the decarbonization of future sustainable electric power systems, allowing a high penetration of distributed renewable energy sources and contributing to the distribution network stability and reliability. To accomplish this, a storage system is required to provide multiple services such as self-consumption, grid support, peak-shaving, etc. The simultaneous activation of controllers operation may lead to conflicts, as a consequence the execution of committed services is not guaranteed. This paper presents and discusses a solution to the exposed issue by developing an engineering support approach to semi-automatically detect and handle conflicts for multi-usage storage systems applications. To accomplish that an ontology is developed and exploited by model-driven engineering mechanisms. The proposed approach is evaluated by implementing a use case example, where detection of conflicts is automatically done at an early design stage. Besides this, exploitable source code for conflicts resolution is generated and used during the design and prototype stages of controllers development. Thus, the proposed engineering support enhances the design and development of storage system controllers, especially for multi-usage applications.

  10. Self Adaptive Air Turbine for Wave Energy Conversion Using Shutter Valve and OWC Heoght Control System

    Energy Technology Data Exchange (ETDEWEB)

    Di Bella, Francis A

    2014-09-29

    An oscillating water column (OWC) is one of the most technically viable options for converting wave energy into useful electric power. The OWC system uses the wave energy to “push or pull” air through a high-speed turbine, as illustrated in Figure 1. The turbine is typically a bi-directional turbine, such as a Wells turbine or an advanced Dennis-Auld turbine, as developed by Oceanlinx Ltd. (Oceanlinx), a major developer of OWC systems and a major collaborator with Concepts NREC (CN) in Phase II of this STTR effort. Prior to awarding the STTR to CN, work was underway by CN and Oceanlinx to produce a mechanical linkage mechanism that can be cost-effectively manufactured, and can articulate turbine blades to improve wave energy capture. The articulation is controlled by monitoring the chamber pressure. Funding has been made available from the U.S. Department of Energy (DOE) to CN (DOE DE-FG-08GO18171) to co-share the development of a blade articulation mechanism for the purpose of increasing energy recovery. However, articulating the blades is only one of the many effective design improvements that can be made to the composite subsystems that constitute the turbine generator system.

  11. A new energy-efficient control approach for space telescope drive system

    Science.gov (United States)

    Zhou, Wangping; Wang, Yong

    Drive control makes the telescope accurately track celestial bodies in spite of external and in-ternal disturbances, and is a key technique to the performance of telescopes. In this paper, we propose a nonlinear adaptive observer based on power reversible approach for high preci-sion position tracking, i.e., space telescopes. The nonlinear adaptive observer automatically estimates the disturbances in drive system, and the observed value is applied to compensate for the real disturbances. With greatly reduced disturbances, the control precision can be ev-idently improved. In conventional drive control, the brake device is often used to slow down the reaction wheel and may waste enormous energy. To avoid those disadvantages, an H-bridge is put forward for wheel speed regulation. Such H-bridge has four independent sections, and each section mainly consists of a power electronic switch and an anti-parallel diode. A pair of diagonal sections is switched on for speeding up the reaction wheel and the other pair act in reverse. During the period of the wheel slowing down, the armature current of drive motor goes through the two path-wise diodes to discharge the battery. Thusly, energy waste is avoided. Based on the disturbance compensation, an optimal controller is designed to minimize an eval-uation function which is made up of a weighted sum of position errors and energy consumption. The outputs of the controller are amplified to control the H-bridge. Simulations are performed in MATLAB language. The results show that high precision control can be obtained by the proposed approach. And the energy consumption will be remarkably reduced.

  12. Simulation Modeling of Intelligent Control Algorithms for Constructing Autonomous Power Supply Systems with Improved Energy Efficiency

    Directory of Open Access Journals (Sweden)

    Gimazov Ruslan

    2018-01-01

    Full Text Available The paper considers the issue of supplying autonomous robots by solar batteries. Low efficiency of modern solar batteries is a critical issue for the whole industry of renewable energy. The urgency of solving the problem of improved energy efficiency of solar batteries for supplying the robotic system is linked with the task of maximizing autonomous operation time. Several methods to improve the energy efficiency of solar batteries exist. The use of MPPT charge controller is one these methods. MPPT technology allows increasing the power generated by the solar battery by 15 – 30%. The most common MPPT algorithm is the perturbation and observation algorithm. This algorithm has several disadvantages, such as power fluctuation and the fixed time of the maximum power point tracking. These problems can be solved by using a sufficiently accurate predictive and adaptive algorithm. In order to improve the efficiency of solar batteries, autonomous power supply system was developed, which included an intelligent MPPT charge controller with the fuzzy logic-based perturbation and observation algorithm. To study the implementation of the fuzzy logic apparatus in the MPPT algorithm, in Matlab/Simulink environment, we developed a simulation model of the system, including solar battery, MPPT controller, accumulator and load. Results of the simulation modeling established that the use of MPPT technology had increased energy production by 23%; introduction of the fuzzy logic algorithm to MPPT controller had greatly increased the speed of the maximum power point tracking and neutralized the voltage fluctuations, which in turn reduced the power underproduction by 2%.

  13. State-of-Charge Balance Using Adaptive Droop Control for Distributed Energy Storage Systems in DC MicroGrid Applications

    DEFF Research Database (Denmark)

    Lu, Xiaonan; Sun, Kai; Guerrero, Josep M.

    2014-01-01

    This paper presents the coordinated control of distributed energy storage systems (DESSs) in DC micro-grids. In order to balance the state-of-charge (SoC) of each energy storage unit (ESU), an SoC-based adaptive droop control method is proposed. In this decentralized control method, the droop...

  14. Output power maximization of low-power wind energy conversion systems revisited: Possible control solutions

    Energy Technology Data Exchange (ETDEWEB)

    Vlad, Ciprian; Munteanu, Iulian; Bratcu, Antoneta Iuliana; Ceanga, Emil [' ' Dunarea de Jos' ' University of Galati, 47, Domneasca, 800008-Galati (Romania)

    2010-02-15

    This paper discusses the problem of output power maximization for low-power wind energy conversion systems operated in partial load. These systems are generally based on multi-polar permanent-magnet synchronous generators, who exhibit significant efficiency variations over the operating range. Unlike the high-power systems, whose mechanical-to-electrical conversion efficiency is high and practically does not modify the global optimum, the low-power systems global conversion efficiency is affected by the generator behavior and the electrical power optimization is no longer equivalent with the mechanical power optimization. The system efficiency has been analyzed by using both the maxima locus of the mechanical power versus the rotational speed characteristics, and the maxima locus of the electrical power delivered versus the rotational speed characteristics. The experimental investigation has been carried out by using a torque-controlled generator taken from a real-world wind turbine coupled to a physically simulated wind turbine rotor. The experimental results indeed show that the steady-state performance of the conversion system is strongly determined by the generator behavior. Some control solutions aiming at maximizing the energy efficiency are envisaged and thoroughly compared through experimental results. (author)

  15. Output power maximization of low-power wind energy conversion systems revisited: Possible control solutions

    International Nuclear Information System (INIS)

    Vlad, Ciprian; Munteanu, Iulian; Bratcu, Antoneta Iuliana; Ceanga, Emil

    2010-01-01

    This paper discusses the problem of output power maximization for low-power wind energy conversion systems operated in partial load. These systems are generally based on multi-polar permanent-magnet synchronous generators, who exhibit significant efficiency variations over the operating range. Unlike the high-power systems, whose mechanical-to-electrical conversion efficiency is high and practically does not modify the global optimum, the low-power systems global conversion efficiency is affected by the generator behavior and the electrical power optimization is no longer equivalent with the mechanical power optimization. The system efficiency has been analyzed by using both the maxima locus of the mechanical power versus the rotational speed characteristics, and the maxima locus of the electrical power delivered versus the rotational speed characteristics. The experimental investigation has been carried out by using a torque-controlled generator taken from a real-world wind turbine coupled to a physically simulated wind turbine rotor. The experimental results indeed show that the steady-state performance of the conversion system is strongly determined by the generator behavior. Some control solutions aiming at maximizing the energy efficiency are envisaged and thoroughly compared through experimental results.

  16. Control Strategies for Smoothing of Output Power of Wind Energy Conversion Systems

    Science.gov (United States)

    Pratap, Alok; Urasaki, Naomitsu; Senju, Tomonobu

    2013-10-01

    This article presents a control method for output power smoothing of a wind energy conversion system (WECS) with a permanent magnet synchronous generator (PMSG) using the inertia of wind turbine and the pitch control. The WECS used in this article adopts an AC-DC-AC converter system. The generator-side converter controls the torque of the PMSG, while the grid-side inverter controls the DC-link and grid voltages. For the generator-side converter, the torque command is determined by using the fuzzy logic. The inputs of the fuzzy logic are the operating point of the rotational speed of the PMSG and the difference between the wind turbine torque and the generator torque. By means of the proposed method, the generator torque is smoothed, and the kinetic energy stored by the inertia of the wind turbine can be utilized to smooth the output power fluctuations of the PMSG. In addition, the wind turbines shaft stress is mitigated compared to a conventional maximum power point tracking control. Effectiveness of the proposed method is verified by the numerical simulations.

  17. Control of base-excited dynamical systems through piezoelectric energy harvesting absorber

    Science.gov (United States)

    Abdelmoula, H.; Dai, H. L.; Abdelkefi, A.; Wang, L.

    2017-09-01

    The spring-mass absorber usually offers a good control to dynamical systems under direct base excitations for a specific value of the excitation frequency. As the vibrational energy of a primary dynamical system is transferred to the absorber, it gets dissipated. In this study, this energy is no longer dissipated but converted to available electrical power by designing efficient energy harvesters. A novel design of a piezoelectric beam installed inside an elastically-mounted dynamical system undergoing base excitations is considered. A design is carried out in order to determine the properties and dimensions of the energy harvester with the constraint of simultaneously decreasing the oscillating amplitudes of the primary dynamical system and increasing the harvested power of the energy harvesting absorber. An analytical model for the coupled system is constructed using Euler-Lagrange principle and Galerkin discretization. Different strategies for controlling the primary structure displacement and enhancing the harvested power as functions of the electrical load resistance and thickness of the beam substrate are performed. The linear polynomial approximation of the system’s key parameters as a function of the beam’s substrate thickness is first carried out. Then, the gradient method is applied to determine the adequate values of the electrical load resistance and thickness of the substrate under the constraints of minimizing the amplitudes of the primary structure or maximizing the levels of the harvested power. After that, an iterative strategy is considered in order to simultaneously minimize the amplitudes of the primary structure and maximize the levels of the harvested power as functions of the thickness of the substrate and electrical load resistance. In addition to harmonic excitations, the coupled system subjected to a white noise is explored. Through this analysis, the load resistance and thickness of the substrate of the piezoelectric energy harvester

  18. Wind energy analysis system

    OpenAIRE

    2014-01-01

    M.Ing. (Electrical & Electronic Engineering) One of the most important steps to be taken before a site is to be selected for the extraction of wind energy is the analysis of the energy within the wind on that particular site. No wind energy analysis system exists for the measurement and analysis of wind power. This dissertation documents the design and development of a Wind Energy Analysis System (WEAS). Using a micro-controller based design in conjunction with sensors, WEAS measure, calcu...

  19. Distributed Cooperative Control of Multi Flywheel Energy Storage System for Electrical Vehicle Fast Charging Stations

    DEFF Research Database (Denmark)

    Sun, Bo; Dragicevic, Tomislav; Quintero, Juan Carlos Vasquez

    2015-01-01

    Plug-in electrical vehicles will play a critical role in future smart grid and sudden connection of electrical vehicles chargers may cause huge power-peaks with high slew-rates on grid. In order to cope with this issue, this paper applies a distributed cooperative control for fast charging station...... with dedicated paralleled flywheel-based energy storage system. The distributed DC-bus signaling method is employed in the power coordination of grid and flywheel converters, and a distributed secondary controller generates DC voltage correction term to adjust the local voltage set-point through a dynamic...... consensus based voltage observer by communicating with its neighbors. The control system can realize the power balancing and DC voltage regulation with low reliance on communications. Finally, real-time hardware-in-the-loop results have been reported in order to verify the feasibility of proposed approach....

  20. Automatic generation control of an interconnected hydrothermal power system considering superconducting magnetic energy storage

    Energy Technology Data Exchange (ETDEWEB)

    Abraham, Rajesh Joseph; Das, D.; Patra, Amit [Department of Electrical Engineering, Indian Institute of Technology, Kharagpur 721 302 (India)

    2007-10-15

    This paper presents the analysis of automatic generation control (AGC) of an interconnected hydrothermal power system in the presence of generation rate constraints (GRCs). The improvement of AGC with the addition of a small capacity superconducting magnetic energy storage (SMES) unit in either, as well as in both the areas are studied. Time domain simulations are used to study the performance of the power system and control logic. The optimal values of the integral gain settings are obtained using integral squared error (ISE) technique by minimising a quadratic performance index. Suitable method for controlling the SMES unit is described. Analysis reveals that SMES unit fitted in either of the areas is as effective as SMES units fitted in both the areas and improves the dynamic performances to a considerable extent following a load disturbance in either of the areas. (author)

  1. Recent Developments of the Modelica"Buildings" Library for Building Energy and Control Systems

    Energy Technology Data Exchange (ETDEWEB)

    Wetter, Michael; Zuo, Wangda; Nouidui, Thierry Stephane

    2011-04-01

    At the Modelica 2009 conference, we introduced the Buildings library, a freely available Modelica library for building energy and control systems. This paper reports the updates of the library and presents example applications for a range of heating, ventilation and air conditioning (HVAC) systems. Over the past two years, the library has been further developed. The number of HVAC components models has been doubled and various components have been revised to increase numerical robustness.The paper starts with an overview of the library architecture and a description of the main packages. To demonstrate the features of the Buildings library, applications that include multizone airflow simulation as well as supervisory and local loop control of a variable air volume (VAV) system are briefly described. The paper closes with a discussion of the current development.

  2. Study and experimental verification of control tuning strategies in a variable speed wind energy conversion system

    Energy Technology Data Exchange (ETDEWEB)

    Zaragoza, Jordi; Pou, Josep; Arias, Antoni [Electronic Engineering Dept., Technical University of Catalonia, Campus Terrassa, C. Colom 1, 08222 Terrassa (Spain); Spiteri, Cyril [Department of Industrial Electrical Power Conversion, University of Malta, Faculty of Engineering, Msida (Malta); Robles, Eider; Ceballos, Salvador [Energy Unit, Robotiker-Tecnalia Technology Corporation, Zamudio, Basque Country (Spain)

    2011-05-15

    This paper analyzes and compares different control tuning strategies for a variable speed wind energy conversion system (WECS) based on a permanent-magnet synchronous generator (PMSG). The aerodynamics of the wind turbine (WT) and a PMSG have been modeled. The control strategy used in this research is composed of three regulators, which may be based on either linear or nonlinear controllers. In this analysis, proportional-integral (PI) linear controllers have been used. Two different tuning strategies are analyzed and compared. The main goal is to enhance the overall performance by achieving a low sensitivity to disturbances and minimal overshoot under variable operating conditions. Finally, the results have been verified by an experimental WECS laboratory prototype. (author)

  3. Coordinated Control of Wind Turbine and Energy Storage System for Reducing Wind Power Fluctuation

    Energy Technology Data Exchange (ETDEWEB)

    Muljadi, Eduard [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Kim, Chunghun [Hanyang University; Chung, Chung Choo [Hanyang University

    2017-11-13

    This paper proposes a coordinated control of wind turbine and energy storage system (ESS). Because wind power (WP) is highly dependent on variable wind speed and could induce a severe stability problem to power system especially when the WP has high penetration level. To solve this problem, many power generation corporations or grid operators recently use the ESS. It has very quick response and good performance for reducing the impact of WP fluctuation but has high cost for its installation. Therefore, it is very important to design the control algorithm considering both ESS capacity and grid reliability. Thus, we propose the control algorithm to mitigate the WP fluctuation by using the coordinated control between wind turbine and ESS considering ESS state of charge (SoC) and the WP fluctuation. From deloaded control according to WP fluctuation and ESS SoC management, we can expect the ESS lifespan expansion and improved grid reliability. The effectiveness of the proposed method is validated in MATLAB/Simulink considering power system including both wind turbine generator and conventional generators which react to system frequency deviation.

  4. An Optimal Control Strategy for DC Bus Voltage Regulation in Photovoltaic System with Battery Energy Storage

    Directory of Open Access Journals (Sweden)

    Muhamad Zalani Daud

    2014-01-01

    Full Text Available This paper presents an evaluation of an optimal DC bus voltage regulation strategy for grid-connected photovoltaic (PV system with battery energy storage (BES. The BES is connected to the PV system DC bus using a DC/DC buck-boost converter. The converter facilitates the BES power charge/discharge to compensate for the DC bus voltage deviation during severe disturbance conditions. In this way, the regulation of DC bus voltage of the PV/BES system can be enhanced as compared to the conventional regulation that is solely based on the voltage-sourced converter (VSC. For the grid side VSC (G-VSC, two control methods, namely, the voltage-mode and current-mode controls, are applied. For control parameter optimization, the simplex optimization technique is applied for the G-VSC voltage- and current-mode controls, including the BES DC/DC buck-boost converter controllers. A new set of optimized parameters are obtained for each of the power converters for comparison purposes. The PSCAD/EMTDC-based simulation case studies are presented to evaluate the performance of the proposed optimized control scheme in comparison to the conventional methods.

  5. An optimal control strategy for DC bus voltage regulation in photovoltaic system with battery energy storage.

    Science.gov (United States)

    Daud, Muhamad Zalani; Mohamed, Azah; Hannan, M A

    2014-01-01

    This paper presents an evaluation of an optimal DC bus voltage regulation strategy for grid-connected photovoltaic (PV) system with battery energy storage (BES). The BES is connected to the PV system DC bus using a DC/DC buck-boost converter. The converter facilitates the BES power charge/discharge to compensate for the DC bus voltage deviation during severe disturbance conditions. In this way, the regulation of DC bus voltage of the PV/BES system can be enhanced as compared to the conventional regulation that is solely based on the voltage-sourced converter (VSC). For the grid side VSC (G-VSC), two control methods, namely, the voltage-mode and current-mode controls, are applied. For control parameter optimization, the simplex optimization technique is applied for the G-VSC voltage- and current-mode controls, including the BES DC/DC buck-boost converter controllers. A new set of optimized parameters are obtained for each of the power converters for comparison purposes. The PSCAD/EMTDC-based simulation case studies are presented to evaluate the performance of the proposed optimized control scheme in comparison to the conventional methods.

  6. Sliding Mode Control of a Variable- Speed Wind Energy Conversion System Using a Squirrel Cage Induction Generator

    Directory of Open Access Journals (Sweden)

    Mohamed Zribi

    2017-05-01

    Full Text Available This paper deals with the control of a variable-speed wind energy conversion (WEC system using a squirrel cage induction generator (SCIG connected to the grid through a back-to-back three phase (AC-DC-AC power converter. The sliding mode control technique is used to control the WEC system. The objective of the controllers is to force the states of the system to track their desired states. One controller is used to regulate the generator speed and the flux so that maximum power is extracted from the wind. Another controller is used to control the grid side converter, which controls the DC bus voltage and the active and reactive powers injected into the grid. The performance of the controlled wind energy conversion system is verified through MATLAB simulations, which show that the controlled system performs well.

  7. Full scale impact testing for environmental and safety control of energy material shipping container systems

    International Nuclear Information System (INIS)

    Seagren, R.D.

    1978-01-01

    Heavily-shielded energy material shipping systems, similar in size and weight to those presently employed to transport irradiated reactor fuel elements, are being destructively tested under dynamic conditions. In these tests, the outer and inner steel shells interact in a complex manner with the massive biological shielding in the system. Results obtained from these tests provide needed information for new design concepts. Containment failure (and the resulting release of radioactive material to the environment which might occur in an extremely severe accident) is most likely through the seals and other ancillary features of the shipping systems. Analyses and experiments provide engineering data on the behavior of these shipping systems under severe accident conditions and information for predicting potential survivability and environmental control with a rational margin of safety

  8. Droop Control Design of Multi-VSC Systems for Offshore Networks to Integrate Wind Energy

    Directory of Open Access Journals (Sweden)

    Muhammad Raza

    2016-10-01

    Full Text Available This research envisages the droop control design of multi voltage source converter systems for offshore networks to integrate wind power plant with the grids. An offshore AC network is formulated by connecting several nearby wind power plants together with AC cables. The net energy in the network is transferred to onshore using voltage source high voltage direct current (VSC-HVDC transmissionsystems. In the proposed configuration, an offshore network is energized by more than one VSC-HVDC system, hereby providing redundancy to continue operation in case of failure in one of the HVDC transmission lines. The power distribution between VSC-HVDC systems is done using a droop control scheme. Frequency droop is implemented to share active power, and voltage droop is implemented to share reactive power. Furthermore, a method of calculating droop gains according to the contribution factor of each converter is presented. The system has been analyzed to evaluate the voltage profile of the network affected by the droop control. Nonlinear dynamic simulation has been performed for the verification of the control principle.

  9. Energy management via Internet. Process control system helps companies save energy; Energiemanagement via Internet. Prozessleitsystem hilft Unternehmen Energie sparen

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2009-02-15

    In view of constantly rising oil and natural gas prices and the demand for environmentally compatible production processes, efficient use of energy is a decisive factor governing the productivity of an industrial company, now more than ever. (orig.)

  10. Evaluation of Seismic Behavior of Steel Braced Frames with Controlled Rocking System and Energy Dissipating Fuses

    Directory of Open Access Journals (Sweden)

    Hassan Amirzehni

    2016-12-01

    Full Text Available The self-centering rocking steel braced frames are new type of seismic lateral-force resisting systems that are developed with aim to limiting structural damages, minimizing residual drifts on systems and creating easy and inexpensive reconstruction capability, after sever earthquakes. In Steel braced frames with controlled rocking system, column bases on seismic resisting frame are not attached to the foundation and the frame allowed to rock freely. The task of restoring the rotated frame to its initial location is on post-tensioned cables, which attaches top of the frame to foundation. The design of post tensioned stands and braced frame members is such that during earthquakes they remain in elastic region. Seismic energy, dissipates by plastic deformations in replaceable elements on each rock of frame. In current research work, the seismic behavior of this type of lateral resisting systems is evaluated. The research conducted on a one bay steel braced frame with controlled rocking system that is analyzed using nonlinear dynamic time history analysis (NLTHA procedure. The frame is subjected to JMA-Kobe and Northridge ground motions records that are scaled to unit, 1.2 and 1.5 times of maximum considered earthquake (MCE ground motion level intensity. Extracted results show that seismic behavior of this type of lateral force resisting systems are so desirable even under MCE ground motion levels. The only anxiety is about occurring fatigue in post-tensioned strands that endangers overall stability of system.

  11. Reduction of external noise of mobile energy facilities by using active noise control system in muffler

    Science.gov (United States)

    Polivaev, O. I.; Kuznetsov, A. N.; Larionov, A. N.; Beliansky, R. G.

    2018-03-01

    The paper describes a method for the reducing emission of low-frequency noise of modern automotive vehicles into the environment. The importance of reducing the external noise of modern mobile energy facilities made in Russia is substantiated. Standard methods for controlling external noise in technology are of low efficiency when low-frequency sound waves are reduced. In this case, it is in the low-frequency zone of the sound range that the main power of the noise emitted by the machinery lies. The most effective way to reduce such sound waves is to use active noise control systems. A design of a muffler using a similar system is presented. This muffler allowed one to reduce the emission of increased noise levels into the environment by 7-11 dB and to increase acoustic comfort at the operator's workplace by 3-5 dB.

  12. Improved energy performance of ammonia recycling system using floating condensing temperature control

    International Nuclear Information System (INIS)

    Lu, Wei; Meng, Zhuo; Sun, Yize; Zhong, Qianwen; Zhu, Helei

    2016-01-01

    Highlights: • Thermodynamic models for the compressor and evaporative condenser were developed. • An evaluation index was proposed to determine the optimal set point. • An algorithm was presented to compute the optimal set point. • Strategies for operating ammonia recycling system were proposed. - Abstract: Aiming at reducing the energy-consumption of ammonia recycling system, we presented floating condensing temperature control to maximize the coefficient of performance (COP) of the system. Firstly, thermodynamic models for the compressor and evaporative condenser were developed respectively. Then, an evaluation index and a solution scheme were proposed to determine the optimal set point of condensing temperature and the corresponding compressor speed. It is found that the system COP can be maximized by controlling the compressor speed to adjust the set point based on any given operating conditions. When the wet-bulb temperature is 22 °C, the system COP could be improved by 19.2–27.6% under floating condensing temperature control.

  13. Atomic Energy Control Act

    International Nuclear Information System (INIS)

    1970-01-01

    This act provides for the establishment of the Atomic Energy Control Board. The board is responsible for the control and supervision of the development, application and use of atomic energy. The board is also considered necessary to enable Canada to participate effectively in measures of international control of atomic energy

  14. Coordinated control of wind generation and energy storage for power system frequency regulation

    Science.gov (United States)

    Baone, Chaitanya Ashok

    Large-scale centralized synchronous generators have long been the primary actors in exercising active power and frequency control, and much of the existing grid control framework is predicated upon their dynamic terminal characteristics. Important among these characteristics is the inertia of such generators. These play key roles in determining the electromechanical stability of the electric power grid. Modern wind generator systems are partially or fully connected to the grid through power electronic interfaces, and hence do not present the same level of inertial coupling. The absence of inertial frequency response from modern wind generator systems is a topic of growing concern in power engineering practice, as the penetration of wind generation is expected to grow dramatically in the next few years. Solutions proposed in the literature have sought to address this problem by seeking to mimic the inherent inertial response characteristics of traditional synchronous generators via control loops added to wind generators. Recent literature has raised concerns regarding this approach, and the work here will further examine its shortcomings, motivating approaches that seek to optimally design for the characteristics of the equipment exercising the control, rather than forcing new technologies to mimic the characteristics of synchronous machines. In particular, this work will develop a new approach to power system frequency regulation, with features suited to distributed energy storage devices such as grid-scale batteries and wind turbine speed and blade pitch control. The dynamic characteristics of these new technologies are treated along with existing mechanisms, such as synchronous machine governor control, to develop a comprehensive multi-input control design approach. To make the method practically feasible for geographically distributed power systems, an observer-based distributed control design utilizing phasor measurement unit (PMU) signals along with local

  15. Modeling and control design of a stand alone wind energy conversion system based on functional model predictive control

    Energy Technology Data Exchange (ETDEWEB)

    Kassem, Ahmed M. [Beni-Suef University, Electrical Dept., Beni Suef (Egypt)

    2012-09-15

    This paper investigates the application of the model predictive control (MPC) approach to control the voltage and frequency of a stand alone wind generation system. This scheme consists of a wind turbine which drives an induction generator feeding an isolated load. A static VAR compensator is connected at the induction generator terminals to regulate the load voltage. The rotor speed, and thereby the load frequency are controlled via adjusting the mechanical power input using the blade pitch-angle. The MPC is used to calculate the optimal control actions including system constraints. To alleviate computational effort and to reduce numerical problems, particularly in large prediction horizon, an exponentially weighted functional model predictive control (FMPC) is employed. Digital simulations have been carried out in order to validate the effectiveness of the proposed scheme. The proposed controller has been tested through step changes in the wind speed and the load impedance. Simulation results show that adequate performance of the proposed wind energy scheme has been achieved. Moreover, this scheme is robust against the parameters variation and eliminates the influence of modeling and measurement errors. (orig.)

  16. Hierarchical Control Design for Shipboard Power System with DC Distribution and Energy Storage aboard Future More-Electric Ships

    DEFF Research Database (Denmark)

    Jin, Zheming; Meng, Lexuan; Guerrero, Josep M.

    2018-01-01

    power system (SPS) with DC distribution and energy storage system (ESS) is picked as study case. To meet the requirement of control and management of such a large-scale mobile power system, a hierarchical control design is proposed in this paper. In order to fully exploit the benefit of ESS, as well...

  17. A Novel Four-Dimensional Energy-Saving and Emission-Reduction System and Its Linear Feedback Control

    Directory of Open Access Journals (Sweden)

    Minggang Wang

    2012-01-01

    Full Text Available This paper reports a new four-dimensional energy-saving and emission-reduction chaotic system. The system is obtained in accordance with the complicated relationship between energy saving and emission reduction, carbon emission, economic growth, and new energy development. The dynamics behavior of the system will be analyzed by means of Lyapunov exponents and equilibrium points. Linear feedback control methods are used to suppress chaos to unstable equilibrium. Numerical simulations are presented to show these results.

  18. Real time implementation and control validation of the wind energy conversion system

    Science.gov (United States)

    Sattar, Adnan

    The purpose of the thesis is to analyze dynamic and transient characteristics of wind energy conversion systems including the stability issues in real time environment using the Real Time Digital Simulator (RTDS). There are different power system simulation tools available in the market. Real time digital simulator (RTDS) is one of the powerful tools among those. RTDS simulator has a Graphical User Interface called RSCAD which contains detail component model library for both power system and control relevant analysis. The hardware is based upon the digital signal processors mounted in the racks. RTDS simulator has the advantage of interfacing the real world signals from the external devices, hence used to test the protection and control system equipments. Dynamic and transient characteristics of the fixed and variable speed wind turbine generating systems (WTGSs) are analyzed, in this thesis. Static Synchronous Compensator (STATCOM) as a flexible ac transmission system (FACTS) device is used to enhance the fault ride through (FRT) capability of the fixed speed wind farm. Two level voltage source converter based STATCOM is modeled in both VSC small time-step and VSC large time-step of RTDS. The simulation results of the RTDS model system are compared with the off-line EMTP software i.e. PSCAD/EMTDC. A new operational scheme for a MW class grid-connected variable speed wind turbine driven permanent magnet synchronous generator (VSWT-PMSG) is developed. VSWT-PMSG uses fully controlled frequency converters for the grid interfacing and thus have the ability to control the real and reactive powers simultaneously. Frequency converters are modeled in the VSC small time-step of the RTDS and three phase realistic grid is adopted with RSCAD simulation through the use of optical analogue digital converter (OADC) card of the RTDS. Steady state and LVRT characteristics are carried out to validate the proposed operational scheme. Simulation results show good agreement with real

  19. Multi input-output fuzzy logic smart controller for a residential hybrid solar-wind-storage energy system

    International Nuclear Information System (INIS)

    Derrouazin, A.; Aillerie, M.; Mekkakia-Maaza, N.; Charles, J.-P.

    2017-01-01

    Highlights: • We present a fuzzy smart controller for hybrid renewable and conventional energy system. • The rules are based on human intelligence and implemented in the smart controller. • Efficient tracking capability of the proposed controller is proofed in this paper by an example. • Excess produced renewable energy is converted to hydrogen for household use . • Considerable electric grid energy saving is highlighted in the proposed controller system. - Abstract: This study concerns the conception and development of an efficient multi input-output fuzzy logic smart controller, to manage the energy flux of a sustainable hybrid power system, based on renewable power sources, integrating solar panels and a wind turbine associated with storage, applied to a typical residential habitat. In the suggested topology, the energy surplus is redirected to an electrolysis system to produce hydrogen suitable for household utilities. To assume a constant access to electricity in case of consumption peak, connection to the grid is also considered as an exceptional rescue resource. The objective of the presented controller is to exploit instantaneously the produced renewable electric energy and insure savings of electric grid energy. The proposed multi input-output fuzzy logic smart controller has been achieved and verified, outcome switches command signals are discussed and the renewable energy system integration ratio is highlighted.

  20. Realization of the Energy Saving of the Environmental Examination Device Temperature Control System in Consideration of Temperature Characteristics

    Science.gov (United States)

    Onogaki, Hitoshi; Yokoyama, Shuichi

    The temperature control of the environmental examination device has loss of the energy consumption to cool it while warming it. This paper proposed a tempareture control system method with energy saving for the enviromental examination device without using cooling in consideration of temperature characteristics.

  1. Energy conservation in industrial buildings. Higher energy efficiency with smart control systems; Energieeinsparung im Gewerbebau. Hoehere Energieeffizienz durch 'intelligente' Regeltechnik

    Energy Technology Data Exchange (ETDEWEB)

    Mayer, Edgar [CentraLine c/o Honeywell GmbH, Schoenaich (Germany)

    2009-07-01

    With smart control systems, the energy conservation potential of industrial buildings could be fully utilized. This means, e.g., that classic control algorithms must be replaced by new solutions. New methods will ensure higher energy efficiency with maximum comfort; they will also prolong the service life and the inspection intervals of the technical facilities. (orig.)

  2. Novel high efficient speed sensorless controller for maximum power extraction from wind energy conversion systems

    International Nuclear Information System (INIS)

    Fathabadi, Hassan

    2016-01-01

    Highlights: • Novel sensorless MPPT technique without drawbacks of other sensor/sensorless methods. • Tracking the actual MPP of WECSs, no tracking the MPP of their wind turbines. • Actually extracting the highest output power from WECSs. • Novel MPPT technique having the MPPT efficiency more than 98.5% for WECSs. • Novel MPPT technique having short convergence time for WECSs. - Abstract: In this study, a novel high accurate sensorless maximum power point tracking (MPPT) method is proposed. The technique tracks the actual maximum power point of a wind energy conversion system (WECS) at which maximum output power is extracted from the system, not the maximum power point of its wind turbine at which maximum mechanical power is obtained from the turbine, so it actually extracts the highest output power from the system. The technique only uses input voltage and current of the converter used in the system, and neither needs any speed sensors (anemometer and tachometer) nor has the drawbacks of other sensor/sensorless based MPPT methods. The technique has been implemented as a MPPT controller by constructing a WECS. Theoretical results, the technique performance, and its advantages are validated by presenting real experimental results. The real static-dynamic response of the MPPT controller is experimentally obtained that verifies the proposed MPPT technique high accurately extracts the highest instant power from wind energy conversion systems with the MPPT efficiency of more than 98.5% and a short convergence time that is only 25 s for the constructed system having a total inertia and friction coefficient of 3.93 kg m 2 and 0.014 N m s, respectively.

  3. Special Issue on Advances in Integrated Energy Systems Design, Control and Optimization

    DEFF Research Database (Denmark)

    Anvari-Moghaddam, Amjad; Guerrero, Josep M.

    2017-01-01

    and novel operation schemes, and new incentives and business models. This revolution is affecting the current paradigm and demanding that energy systems be integrated into multi-carrier energy hubs [1]. It is greatly increasing the interactions between today’s energy systems at various scales (ranging from...... energy costs to all consumers, increase reliability of service and mitigate carbon footprints. However, this plan of action necessitates regulatory frameworks, strategic incentives and business models for efficient deployment....

  4. Evaluation of Strategies to Reducing Traction Energy Consumption of Metro Systems Using an Optimal Train Control Simulation Model

    Directory of Open Access Journals (Sweden)

    Shuai Su

    2016-02-01

    Full Text Available Increasing attention is being paid to the energy efficiency in metro systems to reduce the operational cost and to advocate the sustainability of railway systems. Classical research has studied the energy-efficient operational strategy and the energy-efficient system design separately to reduce the traction energy consumption. This paper aims to combine the operational strategies and the system design by analyzing how the infrastructure and vehicle parameters of metro systems influence the operational traction energy consumption. Firstly, a solution approach to the optimal train control model is introduced, which is used to design the Optimal Train Control Simulator(OTCS. Then, based on the OTCS, the performance of some important energy-efficient system design strategies is investigated to reduce the trains’ traction energy consumption, including reduction of the train mass, improvement of the kinematic resistance, the design of the energy-saving gradient, increasing the maximum traction and braking forces, introducing regenerative braking and timetable optimization. As for these energy-efficient strategies, the performances are finally evaluated using the OTCS with the practical operational data of the Beijing Yizhuang metro line. The proposed approach gives an example to quantitatively analyze the energy reduction of different strategies in the system design procedure, which may help the decision makers to have an overview of the energy-efficient performances and then to make decisions by balancing the costs and the benefits.

  5. Hybrid model predictive control of a residential HVAC system with on-site thermal energy generation and storage

    International Nuclear Information System (INIS)

    Fiorentini, Massimo; Wall, Josh; Ma, Zhenjun; Braslavsky, Julio H.; Cooper, Paul

    2017-01-01

    Highlights: • A comprehensive approach to managing thermal energy in residential buildings. • Solar-assisted HVAC system with on-site energy generation and storage. • Mixed logic-dynamical building model identified using experimental data. • Design and implementation of a logic-dynamical model predictive control strategy. • MPC applied to the Net-Zero Energy house winner of the Solar Decathlon China 2013. - Abstract: This paper describes the development, implementation and experimental investigation of a Hybrid Model Predictive Control (HMPC) strategy to control solar-assisted heating, ventilation and air-conditioning (HVAC) systems with on-site thermal energy generation and storage. A comprehensive approach to the thermal energy management of a residential building is presented to optimise the scheduling of the available thermal energy resources to meet a comfort objective. The system has a hybrid nature with both continuous variables and discrete, logic-driven operating modes. The proposed control strategy is organized in two hierarchical levels. At the high-level, an HMPC controller with a 24-h prediction horizon and a 1-h control step is used to select the operating mode of the HVAC system. At the low-level, each operating mode is optimised using a 1-h rolling prediction horizon with a 5-min control step. The proposed control strategy has been practically implemented on the Building Management and Control System (BMCS) of a Net Zero-Energy Solar Decathlon house. This house features a sophisticated HVAC system comprising of an air-based photovoltaic thermal (PVT) collector and a phase change material (PCM) thermal storage integrated with the air-handling unit (AHU) of a ducted reverse-cycle heat pump system. The simulation and experimental results demonstrated the high performance achievable using an HMPC approach to optimising complex multimode HVAC systems in residential buildings, illustrating efficient selection of the appropriate operating modes

  6. Power Control and Optimization of Photovoltaic and Wind Energy Conversion Systems

    Science.gov (United States)

    Ghaffari, Azad

    Power map and Maximum Power Point (MPP) of Photovoltaic (PV) and Wind Energy Conversion Systems (WECS) highly depend on system dynamics and environmental parameters, e.g., solar irradiance, temperature, and wind speed. Power optimization algorithms for PV systems and WECS are collectively known as Maximum Power Point Tracking (MPPT) algorithm. Gradient-based Extremum Seeking (ES), as a non-model-based MPPT algorithm, governs the system to its peak point on the steepest descent curve regardless of changes of the system dynamics and variations of the environmental parameters. Since the power map shape defines the gradient vector, then a close estimate of the power map shape is needed to create user assignable transients in the MPPT algorithm. The Hessian gives a precise estimate of the power map in a neighborhood around the MPP. The estimate of the inverse of the Hessian in combination with the estimate of the gradient vector are the key parts to implement the Newton-based ES algorithm. Hence, we generate an estimate of the Hessian using our proposed perturbation matrix. Also, we introduce a dynamic estimator to calculate the inverse of the Hessian which is an essential part of our algorithm. We present various simulations and experiments on the micro-converter PV systems to verify the validity of our proposed algorithm. The ES scheme can also be used in combination with other control algorithms to achieve desired closed-loop performance. The WECS dynamics is slow which causes even slower response time for the MPPT based on the ES. Hence, we present a control scheme, extended from Field-Oriented Control (FOC), in combination with feedback linearization to reduce the convergence time of the closed-loop system. Furthermore, the nonlinear control prevents magnetic saturation of the stator of the Induction Generator (IG). The proposed control algorithm in combination with the ES guarantees the closed-loop system robustness with respect to high level parameter uncertainty

  7. Energy management algorithm for an optimum control of a photovoltaic water pumping system

    International Nuclear Information System (INIS)

    Sallem, Souhir; Chaabene, Maher; Kamoun, M.B.A.

    2009-01-01

    The effectiveness of photovoltaic water pumping systems depends on the adequacy between the generated energy and the volume of pumped water. This paper presents an intelligent algorithm which makes decision on the interconnection modes and instants of photovoltaic installation components: battery, water pump and photovoltaic panel. The decision is made by fuzzy rules on the basis of the Photovoltaic Panel Generation (PVPG) forecast during a considered day, on the load required power, and by considering the battery safety. The algorithm aims to extend operation time of the water pump by controlling a switching unit which links the system components with respect to multi objective management criteria. The algorithm implementation demonstrates that the approach extends the pumping period for more than 5 h a day which gives a mean daily improvement of 97% of the water pumped volume.

  8. Advanced Manufacturing for Thermal and Environmental Control Systems: Achieving National Energy Goals

    Energy Technology Data Exchange (ETDEWEB)

    Bogucz, Edward A. [Syracuse Univ., NY (United States)

    2017-02-20

    This project was part of a regional initiative in the five counties of Central New York (CNY) that received funding from the U.S. Department of Energy (DOE) and four other federal agencies through the 2012 Advanced Manufacturing Jobs and Innovation Accelerator Challenge (AMJIAC). The CNY initiative was focused on cultivating the emergent regional cluster in “Advanced Manufacturing for Thermal and Environmental Control (AM-TEC).” As one component of the CNY AM-TEC initiative, the DOE-funded project supported five research & development seed projects that strategically targeted: 1) needs and opportunities of CNY AM-TEC companies, and 2) the goal of DOE’s Advanced Manufacturing Office (AMO) to reduce energy consumption by 50% across product life-cycles over 10 years. The project also sought to fulfill the AMO mission of developing and demonstrating new, energy-efficient processing and materials technologies at a scale adequate to prove their value to manufacturers and spur investment. The five seed projects demonstrated technologies and processes that can reduce energy intensity and improve production as well as use less energy throughout their lifecycles. The project was conducted over three years in two 18-month budget periods. During the first budget period, two projects proposed in the original AMJAIC application were successfully completed: Seed Project 1 focused on saving energy in heat transfer processes via development of nano structured surfaces to significantly increase heat flux; Seed Project 2 addressed saving energy in data centers via subzero cooling of the computing processors. Also during the first budget period, a process was developed and executed to select a second round of seed projects via a competitive request for proposals from regional companies and university collaborators. Applicants were encouraged to form industry-academic partnerships to leverage experience and resources of public and private sectors in the CNY region. Proposals were

  9. A Flywheel Energy Storage System Based on a Doubly Fed Induction Machine and Battery for Microgrid Control

    Directory of Open Access Journals (Sweden)

    Thai-Thanh Nguyen

    2015-06-01

    Full Text Available Microgrids are eco-friendly power systems because they use renewable sources such as solar and wind power as the main power source. However, the stochastic nature of wind and solar power is a considerable challenge for the efficient operation of microgrids. Microgrid operations have to satisfy quality requirements in terms of the frequency and voltage. To overcome these problems, energy storage systems for short- and long-term storage are used with microgrids. Recently, the use of short-term energy storage systems such as flywheels has attracted significant interest as a potential solution to this problem. Conventional flywheel energy storage systems exhibit only one control mode during operation: either smoothing wind power control or frequency control. In this paper, we propose a new flywheel energy storage system based on a doubly fed induction machine and a battery for use with microgrids. The new flywheel energy storage system can be used not only to mitigate wind power fluctuations, but also to control the frequency as well as the voltage of the microgrid during islanded operation. The performance of the proposed flywheel energy storage system is investigated through various simulations using MATLAB/Simulink software. In addition, a conventional flywheel energy storage system based on a doubly fed induction machine is simulated and its performance compared with that of the proposed one.

  10. Variable flow controls of closed system pumps for energy savings in maritime power systems

    OpenAIRE

    Su, Chun-Lien; Liao, Chi-Hsiang; Chou, Tso-Chu; Chou, Ming-Hung; Guerrero, Josep M.

    2016-01-01

    Pumps are extensively used in maritime industries as marine vessels utilize a wide range of pumps and pumping techniques to transfer and distribute all types of air and fluids. The electrical energy consumed by the various motors accounts for about 70% of a vessel’s total power consumption, and this presents a problem in unique marine environments. Such situations are especially conducive to energy-saving strategies using variable frequency drives (VFDs) in centrifugal load service. This pape...

  11. Dynamic modeling, experimental evaluation, optimal design and control of integrated fuel cell system and hybrid energy systems for building demands

    Science.gov (United States)

    Nguyen, Gia Luong Huu

    obtained experimental data, the research studied the control of airflow to regulate the temperature of reactors within the fuel processor. The dynamic model provided a platform to test the dynamic response for different control gains. With sufficient sensing and appropriate control, a rapid response to maintain the temperature of the reactor despite an increase in power was possible. The third part of the research studied the use of a fuel cell in conjunction with photovoltaic panels, and energy storage to provide electricity for buildings. This research developed an optimization framework to determine the size of each device in the hybrid energy system to satisfy the electrical demands of buildings and yield the lowest cost. The advantage of having the fuel cell with photovoltaic and energy storage was the ability to operate the fuel cell at baseload at night, thus reducing the need for large battery systems to shift the solar power produced in the day to the night. In addition, the dispatchability of the fuel cell provided an extra degree of freedom necessary for unforeseen disturbances. An operation framework based on model predictive control showed that the method is suitable for optimizing the dispatch of the hybrid energy system.

  12. Comparison of three topologies and controls of a hybrid energy storage system for microgrids

    International Nuclear Information System (INIS)

    Etxeberria, A.; Vechiu, I.; Camblong, H.; Vinassa, J.-M.

    2012-01-01

    Highlight: ► A microgrid with high penetration of renewable sources is analysed. ► A storage system formed by a supercapacitor and a vanadium redox battery is used. ► Three topologies to connect the storage devices and manage the microgrid are compared. ► Effect of renewable sources and grid disconnection are simulated. ► The feasibility, power losses and THD of each topology are compared. - Abstract: A high penetration rate of the Renewable Energy Sources (RES) can create stability, reliability and power quality problems in the main electrical grid. The microgrid should be a feasible alternative to solve these issues. As it is a weak electrical grid, the microgrid is very sensitive to any variation and consequently an Energy Storage System (ESS) is necessary to reduce their effect. A microgrid needs an ESS with high energy and power densities, but none of the currently available storage technologies satisfies both requirements at the same time. Consequently, it is necessary to associate more than one storage technology creating a Hybrid Energy Storage System (HESS). The objective of this work is to compare by means of simulations three different topologies that are used to control a HESS formed by a SuperCapacitor (SC) bank and a Vanadium Redox Battery (VRB). The compared topologies are the parallel active topology, the floating topology and the Three-Level Neutral Point Clamped (3LNPC) converter topology. The analysed microgrid is formed by the mentioned HESS and different renewable energy sources. This microgrid is interconnected to a weak grid based on a Diesel Generator (DG). Two case studies have been analysed: the effect of the RES while the microgrid is connected to the weak grid and the effect of the disconnection of the microgrid from the weak grid. The different topologies are compared analysing their capability of facing the mentioned variations, their power losses and their Total Harmonic Distortion (THD). The Matlab/Simulink software and the

  13. Online optimal control of variable refrigerant flow and variable air volume combined air conditioning system for energy saving

    International Nuclear Information System (INIS)

    Zhu, Yonghua; Jin, Xinqiao; Du, Zhimin; Fang, Xing

    2015-01-01

    The variable refrigerant flow (VRF) and variable air volume (VAV) combined air conditioning system can solve the problem of the VRF system in outdoor air ventilation while taking advantage of its high part load energy efficiency. Energy performance of the combined air conditioning system can also be optimized by joint control of both the VRF and the VAV parts. A model-based online optimal control strategy for the combined air conditioning system is presented. Simplified adaptive models of major components of the combined air conditioning system are firstly developed for predicting system performances. And a cost function in terms of energy consumption and thermal comfort is constructed. Genetic algorithm is used to search for the optimal control sets. The optimal control strategy is tested and evaluated through two case studies based on the simulation platform. Results show that the optimal strategy can effectively reduce energy consumption of the combined air conditioning system while maintaining acceptable thermal comfort. - Highlights: • A VRF and VAV combined system is proposed. • A model-based online optimal control strategy is proposed for the combined system. • The strategy can reduce energy consumption without sacrificing thermal comfort. • Novel simplified adaptive models are firstly developed for the VRF system

  14. A Hybrid Estimator for Active/Reactive Power Control of Single-Phase Distributed Generation Systems with Energy Storage

    DEFF Research Database (Denmark)

    Pahlevani, Majid; Eren, Suzan; Guerrero, Josep M.

    2016-01-01

    This paper presents a new active/reactive power closed-loop control system for a hybrid renewable energy generation system used for single-phase residential/commercial applications. The proposed active/reactive control method includes a hybrid estimator, which is able to quickly and accurately es...

  15. A whole process quality control system for energy measuring instruments inspection based on IOT technology

    Science.gov (United States)

    Yin, Bo; Liu, Li; Wang, Jiahan; Li, Xiran; Liu, Zhenbo; Li, Dewei; Wang, Jun; Liu, Lu; Wu, Jun; Xu, Tingting; Cui, He

    2017-10-01

    Electric energy measurement as a basic work, an accurate measurements play a vital role for the economic interests of both parties of power supply, the standardized management of the measurement laboratory at all levels is a direct factor that directly affects the fairness of measurement. Currently, the management of metering laboratories generally uses one-dimensional bar code as the recognition object, advances the testing process by manual management, most of the test data requires human input to generate reports. There are many problems and potential risks in this process: Data cannot be saved completely, cannot trace the status of inspection, the inspection process isn't completely controllable and so on. For the provincial metrology center's actual requirements of the whole process management for the performance test of the power measuring appliances, using of large-capacity RF tags as a process management information media, we developed a set of general measurement experiment management system, formulated a standardized full performance test process, improved the raw data recording mode of experimental process, developed a storehouse automatic inventory device, established a strict test sample transfer and storage system, ensured that all the raw data of the inspection can be traced back, achieved full life-cycle control of the sample, significantly improved the quality control level and the effectiveness of inspection work.

  16. The energy control

    International Nuclear Information System (INIS)

    2002-01-01

    Because of strong constraints, the energy control has not been a priority of the public choices. With the market liberalization, the framework of the energy control is modified. But the new program became not sufficient. This study aims to present the necessary new policy of the energy control, which must be integrated in the attitudes and must imply the local government. (A.L.B.)

  17. Quantifying demand flexibility of power-to-heat and thermal energy storage in the control of building heating systems

    DEFF Research Database (Denmark)

    Finck, Christian; Li, Rongling; Kramer, Rick

    2018-01-01

    restricted by power-to-heat conversion such as heat pumps and thermal energy storage possibilities of a building. To quantify building demand flexibility, it is essential to capture the dynamic response of the building energy system with thermal energy storage. To identify the maximum flexibility a building......’s energy system can provide, optimal control is required. In this paper, optimal control serves to determine in detail demand flexibility of an office building equipped with heat pump, electric heater, and thermal energy storage tanks. The demand flexibility is quantified using different performance...... of TES and power-to-heat in any case of charging, discharging or idle mode. A simulation case study is performed showing that a water tank, a phase change material tank, and a thermochemical material tank integrated with building heating system can be designed to provide flexibility with optimal control....

  18. Energy management system. Opti-dmaX Control; Sistema de administracion de energia. Control Opti-dmaX

    Energy Technology Data Exchange (ETDEWEB)

    Automatizacion, Productividad y Calidad S.A. de C.V. Puebla (Mexico)

    2005-07-01

    The electrical energy is an essential element in the activities of the present world. Optimizing its consumption represents a competitive advantage for the companies, since the operation costs would be reduced as well as the negative impact to the environment. In billing the electrical energy the tariffs consider: the consumption, the demand, the power and the schedule of use for the medium and large companies. With the Opti-dmaX system the necessary information for the correct administration of the electrical energy consumption is obtained from the measurement in the strategic points of the installation. At the same time, the processes and services are controlled, maintaining an efficient power operation that diminishes operative costs. [Spanish] La energia electrica es un elemento indispensable en las actividades del mundo actual, y optimizar su consumo, representa una ventaja competitiva para las empresas, ya que se consigue reducir los costos de operacion y el impacto al ambiente. En la facturacion de la energia electrica las tarifas consideran: el consumo, la demanda, la potencia y el horario de uso para las medianas y grandes empresas. Con el sistema Opti-dmaX se obtiene la informacion necesaria para la correcta administracion del consumo de energia electrica a partir de la medicion en los puntos estrategicos de la instalacion. A su vez, se controlan los procesos y servicios, manteniendo una operacion energetica eficiente que minimiza los costos operativos.

  19. Monitoring and Control by Virtual Tools of an Educational Renewable Energy System

    Directory of Open Access Journals (Sweden)

    Gligor Adrian

    2009-12-01

    Full Text Available The scope of the present paper is to present the architecture and design of an effective tool useful for monitoring, maintenance and training of specialists in the field of photovoltaic renewable energy Among renewable energy resources, solar energy represents an easy to use, accessible and green source of energy. An important goal is the efficient use of solar energy which can only be achieved by the knowledge of solar datum and equipment characteristics from a studied area. Based on this idea, the paper presents a concept of virtual tools developed on web technologies and virtual instrumentation for monitoring and control of solar renewable energy. These tools are mainly designed as a base for a virtual laboratory that can be used for the study of photovoltaic and thermal solar energy parameters, representing, by didactical point of view, a handful way for students to study the phenomenology and also a training tool for specialists in the field of solar photovoltaic energy.

  20. Small Wind Energy Systems

    DEFF Research Database (Denmark)

    Simões, Marcelo Godoy; Farret, Felix Alberto; Blaabjerg, Frede

    2017-01-01

    considered when selecting a generator for a wind power plant, including capacity of the AC system, types of loads, availability of spare parts, voltage regulation, technical personal and cost. If several loads are likely inductive, such asphase-controlled converters, motors and fluorescent lights......This chapter intends to serve as a brief guide when someone is considering the use of wind energy for small power applications. It is discussed that small wind energy systems act as the major energy source for residential or commercial applications, or how to make it part of a microgrid...... as a distributed generator. In this way, sources and loads are connected in such a way to behave as a renewable dispatch center. With this regard, non-critical loads might be curtailed or shed during times of energy shortfall or periods of high costs of energy production. If such a wind energy system is connected...

  1. Filtering and Control of High Speed Motor Current in a Flywheel Energy Storage System

    Science.gov (United States)

    Kenny, Barbara H.; Santiago, Walter

    2004-01-01

    The NASA Glenn Research Center has been developing technology to enable the use of high speed flywheel energy storage units in future spacecraft for the last several years. An integral part of the flywheel unit is the three phase motor/generator that is used to accelerate and decelerate the flywheel. The motor/generator voltage is supplied from a pulse width modulated (PWM) inverter operating from a fixed DC voltage supply. The motor current is regulated through a closed loop current control that commands the necessary voltage from the inverter to achieve the desired current. The current regulation loop is the innermost control loop of the overall flywheel system and, as a result, must be fast and accurate over the entire operating speed range (20,000 to 60,000 rpm) of the flywheel. The voltage applied to the motor is a high frequency PWM version of the DC bus voltage that results in the commanded fundamental value plus higher order harmonics. Most of the harmonic content is at the switching frequency and above. The higher order harmonics cause a rapid change in voltage to be applied to the motor that can result in large voltage stresses across the motor windings. In addition, the high frequency content in the motor causes sensor noise in the magnetic bearings that leads to disturbances for the bearing control. To alleviate these problems, a filter is used to present a more sinusoidal voltage to the motor/generator. However, the filter adds additional dynamics and phase lag to the motor system that can interfere with the performance of the current regulator. This paper will discuss the tuning methodology and results for the motor/generator current regulator and the impact of the filter on the control. Results at speeds up to 50,000 rpm are presented.

  2. Particle swarm optimization based fuzzy logic controller for autonomous green power energy system with hydrogen storage

    International Nuclear Information System (INIS)

    Safari, S.; Ardehali, M.M.; Sirizi, M.J.

    2013-01-01

    Highlights: ► Optimized fuzzy logic controller for a hybrid green power system is developed. ► PSO algorithm is used to optimize membership functions of controller. ► Optimized fuzzy logic controller results in lower O and M costs and LPSP. ► Optimization results in less variation of battery state of charge. - Abstract: The objective of this study is to develop an optimized fuzzy logic controller (FLC) for operating an autonomous hybrid green power system (HGPS) based on the particle swarm optimization (PSO) algorithm. An electrolyzer produces hydrogen from surplus energy generated by the wind turbine and photovoltaic array of HGPS for later use by a fuel cell. The PSO algorithm is used to optimize membership functions of the FLC. The FLC inputs are (a) net power flow and (b) batteries state of charge (SOC) and FLC output determines the time for hydrogen production or consumption. Actual data for weekly residential load, wind speed, ambient temperature, and solar irradiation are used for performance simulation and analysis of the HGPS examined. The weekly operation and maintenance (O and M) costs and the loss of power supply probability (LPSP) are considered in the optimization procedure. It is determined that FLC optimization results in (a) reduced fluctuations in batteries SOC which translates into longer life for batteries and the average SOC is increased by 6.18% and (b) less working hours for fuel cell, when the load is met by wind and PV. It is found that the optimized FLC results in lower O and M costs and LPSP by 57% and 33%, respectively, as compared to its un-optimized counterpart. In addition, a reduction of 18% in investment cost is achievable by optimal sizing and reducing the capacity of HGPS equipment.

  3. Power control based on particle swarm optimization of grid-connected inverter for hybrid renewable energy system

    International Nuclear Information System (INIS)

    García-Triviño, Pablo; Gil-Mena, Antonio José; Llorens-Iborra, Francisco; García-Vázquez, Carlos Andrés; Fernández-Ramírez, Luis M.; Jurado, Francisco

    2015-01-01

    Highlights: • Three PSO-based PI controllers for a grid-connected inverter were presented. • Two online PSO-based PI controllers were compared with an offline PSO-tuned PI. • The HRES and the inverter were evaluated under power changes and grid voltage sags. • Online ITAE-based PSO reduced ITAE (current THD) by 15.24% (5.32%) versus offline one. - Abstract: This paper is focused on the study of particle swarm optimization (PSO)-based PI controllers for the power control of a grid-connected inverter supplied from a hybrid renewable energy system. It is composed of two renewable energy sources (wind turbine and photovoltaic – PV – solar panels) and two energy storage systems (battery and hydrogen system, integrated by fuel cell and electrolyzer). Three PSO-based PI controllers are implemented: (1) conventional PI controller with offline tuning by PSO algorithm based on the integral time absolute error (ITAE) index; (2) PI controllers with online self-tuning by PSO algorithm based on the error; and (3) PI controllers with online self-tuning by PSO algorithm based on the ITAE index. To evaluate and compare the three controllers, the hybrid renewable energy system and the grid-connected inverter are simulated under changes in the active and reactive power values, as well as under a grid voltage sag. The results show that the online PSO-based PI controllers that optimize the ITAE index achieves the best response

  4. Parameter optimization via cuckoo optimization algorithm of fuzzy controller for energy management of a hybrid power system

    International Nuclear Information System (INIS)

    Berrazouane, S.; Mohammedi, K.

    2014-01-01

    Highlights: • Optimized fuzzy logic controller (FLC) for operating a standalone hybrid power system based on cuckoo search algorithm. • Comparison between optimized fuzzy logic controller based on cuckoo search and swarm intelligent. • Loss of power supply probability and levelized energy cost are introduced. - Abstract: This paper presents the development of an optimized fuzzy logic controller (FLC) for operating a standalone hybrid power system based on cuckoo search algorithm. The FLC inputs are batteries state of charge (SOC) and net power flow, FLC outputs are the power rate of batteries, photovoltaic and diesel generator. Data for weekly solar irradiation, ambient temperature and load profile are used to tune the proposed controller by using cuckoo search algorithm. The optimized FLC is able to minimize loss of power supply probability (LPSP), excess energy (EE) and levelized energy cost (LEC). Moreover, the results of CS optimization are better than of particle swarm optimization PSO for fuzzy system controller

  5. A Voltage and Frequency Control Strategy for Stand-Alone Full Converter Wind Energy Conversion Systems

    Directory of Open Access Journals (Sweden)

    Andrés Peña Asensio

    2018-02-01

    Full Text Available This paper addresses the design and analysis of a voltage and frequency control (VFC strategy for full converter (FC-based wind energy conversion systems (WECSs and its applicability for the supply of an isolated load. When supplying an isolated load, the role of the back-to-back converters in the FC must change with respect to a grid-connected application. Voltage and frequency are established by the FC line side converter (LSC, while the generator side converter (GSC is responsible for maintaining constant voltage in the DC link. Thus, the roles of the converters in the WECS are inverted. Under such control strategies, the LSC will automatically supply the load power and hence, in order to maintain a stable operation of the WECS, the wind turbine (WT power must also be controlled in a load-following strategy. The proposed VFC is fully modelled and a stability analysis is performed. Then, the operation of the WECS under the proposed VFC is simulated and tested on a real-time test bench, demonstrating the performance of the VFC for the isolated operation of the WECS.

  6. Atomic Energy Control Board

    International Nuclear Information System (INIS)

    Blackman, N.S.; Gummer, W.K.

    1982-02-01

    This paper has been prepared to provide an overview of the responsibilities and activities of the Atomic Energy Control Board. It is designed to address questions that are often asked concerning the establishment of the Atomic Energy Control Board, its enabling legislation, licensing and compliance activities, federal-provincial relationships, international obligations, and communications with the public

  7. Energy infrastructure: hydrogen energy system

    Energy Technology Data Exchange (ETDEWEB)

    Veziroglu, T N

    1979-02-01

    In a hydrogen system, hydrogen is not a primary source of energy, but an intermediary, an energy carrier between the primary energy sources and the user. The new unconventional energy sources, such as nuclear breeder reactors, fusion reactors, direct solar radiation, wind energy, ocean thermal energy, and geothermal energy have their shortcomings. These shortcomings of the new sources point out to the need for an intermediary energy system to form the link between the primary energy sources and the user. In such a system, the intermediary energy form must be transportable and storable; economical to produce; and if possible renewable and pollution-free. The above prerequisites are best met by hydrogen. Hydrogen is plentiful in the form of water. It is the cheapest synthetic fuel to manufacture per unit of energy stored in it. It is the least polluting of all of the fuels, and is the lightest and recyclable. In the proposed system, hydrogen would be produced in large plants located away from the consumption centers at the sites where primary new energy sources and water are available. Hydrogen would then be transported to energy consumption centers where it would be used in every application where fossil fuels are being used today. Once such a system is established, it will never be necessary to change to any other energy system.

  8. Comparing Whole Building Energy Implications of Sidelighting Systems with Alternate Manual Blind Control Algorithms

    Directory of Open Access Journals (Sweden)

    Christopher Dyke

    2015-05-01

    Full Text Available Currently, there is no manual blind control guideline used consistently throughout the energy modeling community. This paper identifies and compares five manual blind control algorithms with unique control patterns and reports blind occlusion, rate of change data, and annual building energy consumption. The blind control schemes detailed here represent five reasonable candidates for use in lighting and energy simulation based on difference driving factors. This study was performed on a medium-sized office building using EnergyPlus with the internal daylight harvesting engine. Results show that applying manual blind control algorithms affects the total annual consumption of the building by as much as 12.5% and 11.5% for interior and exterior blinds respectively, compared to the Always Retracted blinds algorithm. Peak demand was also compared showing blind algorithms affected zone load sizing by as much as 9.8%. The alternate algorithms were tested for their impact on American Society of Heating, Refrigeration and Air-Conditioning Engineers (ASHRAE Guideline 14 calibration metrics and all models were found to differ from the original calibrated baseline by more than the recommended ±15% for coefficient of variance of the mean square error (CVRMSE and ±5% for normalized mean bias error (NMBE. The paper recommends that energy modelers use one or more manual blind control algorithms during design stages when making decisions about energy efficiency and other design alternatives.

  9. Energy-Shaping of Port-Controlled Hamiltonian Systems by Interconnection

    NARCIS (Netherlands)

    Ortega, Romeo; Schaft, Arjan van der; Maschke, Bernhard; Escobar, Gerardo

    1999-01-01

    Passivity-based control (PBC) has shown to be very powerful to design robust controllers for physical systems described by Euler-Lagrange (EL) equations of motion. The application of PBC in regulation problems of mechanical systems yields controllers that have a clear physical interpretation in

  10. An energy-saving set-point optimizer with a sliding mode controller for automotive air-conditioning/refrigeration systems

    International Nuclear Information System (INIS)

    Huang, Yanjun; Khajepour, Amir; Ding, Haitao; Bagheri, Farshid; Bahrami, Majid

    2017-01-01

    Highlights: • A novel two-layer energy-saving controller for automotive A/C-R system is developed. • A set-point optimizer at the outer loop is designed based on the steady state model. • A sliding mode controller in the inner loop is built. • Extensively experiments studies show that about 9% energy can be saving by this controller. - Abstract: This paper presents an energy-saving controller for automotive air-conditioning/refrigeration (A/C-R) systems. With their extensive application in homes, industry, and vehicles, A/C-R systems are consuming considerable amounts of energy. The proposed controller consists of two different time-scale layers. The outer or the slow time-scale layer called a set-point optimizer is used to find the set points related to energy efficiency by using the steady state model; whereas, the inner or the fast time-scale layer is used to track the obtained set points. In the inner loop, thanks to its robustness, a sliding mode controller (SMC) is utilized to track the set point of the cargo temperature. The currently used on/off controller is presented and employed as a basis for comparison to the proposed controller. More importantly, the real experimental results under several disturbed scenarios are analysed to demonstrate how the proposed controller can improve performance while reducing the energy consumption by 9% comparing with the on/off controller. The controller is suitable for any type of A/C-R system even though it is applied to an automotive A/C-R system in this paper.

  11. Renewable generation and demand response integration in micro-grids. Development of a new energy management and control system

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez-Bel, C.; Escriva-Escriva, G.; Alcazar-Ortega, M. [Institute for Energy Engineering, Universitat Politecnica de Valencia, Valencia (Spain)

    2013-11-15

    The aim of this research resides in the development of an energy management and control system to control a micro-grid based on the use of renewable generation and demand resources to introduce the application of demand response concepts to the management of micro-grids in order to effectively integrate the demand side as an operation resource for the grid and improve energy efficiency of the elements. As an additional result, the evaluation of reductions in the total amount of CO2 emitted into the atmosphere due to the improvement of the energy efficiency of the system is assessed.

  12. Electrical energy systems

    CERN Document Server

    El-Hawary, Mohamed E

    2007-01-01

    Features discussions ranging from the technical aspects of generation, transmission, distribution, and utilization to power system components, theory, protection, and the energy control center that offer an introduction to effects of deregulating electric power systems, blackouts and their causes, and minimizing their effects.

  13. Indirect Load Control for Energy Storage Systems Using Incentive Pricing under Time-of-Use Tariff

    Directory of Open Access Journals (Sweden)

    Mu-Gu Jeong

    2016-07-01

    Full Text Available Indirect load control (ILC is a method by which the customer determines load reduction of electricity by using a price signal. One of the ILCs is a time-of-use (TOU tariff, which is the most commonly used time-varying retail pricing. Under the TOU tariff, the customer can reduce the energy cost through an energy storage system (ESS. However, because this tariff is fixed for several months, the ESS operation does not truly reflect the wholesale market price, which could widely fluctuate. To overcome this limitation, this paper proposes an incentive pricing method in which the load-serving entity (LSE gives the incentive pricing signal to the customers with ESSs. Because the ESS charging schedule is determined by the customer through ILC, a bilevel optimization problem that includes the customer optimization problem is utilized to determine the incentive pricing signal. Further, the bilevel optimization problem is reformulated into a one-level problem to be solved by an interior point method. In the proposed incentive scheme: (1 the social welfare increases and (2 the increased social welfare can be equitably divided between the LSE and the customer; and (3 the proposed incentive scheme leads the customer to voluntarily follow the pricing signal.

  14. The development of control and monitoring system on marine current renewable energy Case study: strait of Toyapakeh - Nusa Penida, Bali

    Science.gov (United States)

    Arief, I. S.; Suherman, I. H.; Wardani, A. Y.; Baidowi, A.

    2017-05-01

    Control and monitoring system is a continuous process of securing the asset in the Marine Current Renewable Energy. A control and monitoring system is existed each critical components which is embedded in Failure Mode Effect Analysis (FMEA) method. As the result, the process in this paper developed through a matrix sensor. The matrix correlated to critical components and monitoring system which supported by sensors to conduct decision-making.

  15. Comparison of strategies for model predictive control for home heating in future energy systems

    DEFF Research Database (Denmark)

    Vogler-Finck, Pierre Jacques Camille; Popovski, Petar; Wisniewski, Rafal

    2017-01-01

    Model predictive control is seen as one of the key future enabler in increasing energy efficiency in buildings. This paper presents a comparison of the performance of the control for different formulations of the objective function. This comparison is made in a simulation study on a single buildi...

  16. Smart energy management system

    Science.gov (United States)

    Desai, Aniruddha; Singh, Jugdutt

    2010-04-01

    Peak and average energy usage in domestic and industrial environments is growing rapidly and absence of detailed energy consumption metrics is making systematic reduction of energy usage very difficult. Smart energy management system aims at providing a cost-effective solution for managing soaring energy consumption and its impact on green house gas emissions and climate change. The solution is based on seamless integration of existing wired and wireless communication technologies combined with smart context-aware software which offers a complete solution for automation of energy measurement and device control. The persuasive software presents users with easy-to-assimilate visual cues identifying problem areas and time periods and encourages a behavioural change to conserve energy. The system allows analysis of real-time/statistical consumption data with the ability to drill down into detailed analysis of power consumption, CO2 emissions and cost. The system generates intelligent projections and suggests potential methods (e.g. reducing standby, tuning heating/cooling temperature, etc.) of reducing energy consumption. The user interface is accessible using web enabled devices such as PDAs, PCs, etc. or using SMS, email, and instant messaging. Successful real-world trial of the system has demonstrated the potential to save 20 to 30% energy consumption on an average. Low cost of deployment and the ability to easily manage consumption from various web enabled devices offers gives this system a high penetration and impact capability offering a sustainable solution to act on climate change today.

  17. Dynamic modelling and robust control of a wind energy conversion system

    NARCIS (Netherlands)

    Steinbuch, M.

    1989-01-01

    The application of wind energy conversion systems for the production of electrical energy requires a cheap and reliable operation. Especially at high wind velocities fluctuations from the wind field result in large mechanical loads of the wind turbine. Also fluctuations in the grid voltage may yield

  18. Autonomous Active Power Control for Islanded AC Microgrids with Photovoltaic Generation and Energy Storage System

    DEFF Research Database (Denmark)

    Wu, Dan; Tang, Fen; Dragicevic, Tomislav

    2014-01-01

    In an islanded AC microgrid with distributed energy storage system (ESS), photovoltaic (PV) generation and loads, a coordinated active power regulation is required to ensure efficient utilization of renewable energy, while keeping the ESS from overcharge and over discharge conditions. In this paper...

  19. Load Shifting Control and Management of Domestic Microgeneration Systems for Improved Energy Efficiency and Comfort

    DEFF Research Database (Denmark)

    Anvari-Moghaddam, Amjad; Quintero, Juan Carlos Vasquez; Guerrero, Josep M.

    2015-01-01

    In this paper, an intelligent energy management system based on energy saving and user’s comfort is introduced and applied to a residential smart home as a case study. The proposed multi-objective mixed-integer nonlinear programming (MINLP)-based architecture takes the advantages of several key...

  20. Wind energy systems

    Science.gov (United States)

    Stewart, H. J.

    1978-01-01

    A discussion on wind energy systems involved with the DOE wind energy program is presented. Some of the problems associated with wind energy systems are discussed. The cost, efficiency, and structural design of wind energy systems are analyzed.

  1. Designing an Energy Storage System Fuzzy PID Controller for Microgrid Islanded Operation

    OpenAIRE

    Jong-Yul Kim; Hak-Man Kim; Seul-Ki Kim; Jin-Hong Jeon; Heung-Kwan Choi

    2011-01-01

    Recently, interest in microgrids, which are composed of distributed generation (DG), distributed storage (DS), and loads, has been growing as a potentially effective clean energy system to mitigate against climate change. The microgrid is operated in the grid-connected mode and the islanded mode according to the conditions of the upstream power grid. The role of the energy storage system (ESS) is especially important to maintain constant the frequency and voltage of an islanded microgrid. For...

  2. L1 Adaptive Speed Control of a Small Wind Energy Conversion System for Maximum Power Point Tracking

    DEFF Research Database (Denmark)

    Zhao, Haoran; Wu, Qiuwei; Rasmussen, Claus Nygaard

    2014-01-01

    This paper presents the design of an L1 adaptive controller for maximum power point tracking (MPPT) of a small variable speed Wind Energy Conversion System (WECS). The proposed controller generates the optimal torque command for the vector controlled generator side converter (GSC) based on the wi......) is used to carry out case studies using Matlab/Simulink. The case study results show that the designed L1 adaptive controller has good tracking performance even with unmodeled dynamics and in the presence of parameter uncertainties and unknown disturbances.......This paper presents the design of an L1 adaptive controller for maximum power point tracking (MPPT) of a small variable speed Wind Energy Conversion System (WECS). The proposed controller generates the optimal torque command for the vector controlled generator side converter (GSC) based on the wind...

  3. A rule-based phase control methodology for a slider-crank wave energy converter power take-off system

    Energy Technology Data Exchange (ETDEWEB)

    Sang, Yuanrui; Karayaka, H. Bora; Yan, Yanjun; Zhang, James Z.; Bogucki, Darek; Yu, Yi-Hsiang

    2017-09-01

    The slider crank is a proven mechanical linkage system with a long history of successful applications, and the slider-crank ocean wave energy converter (WEC) is a type of WEC that converts linear motion into rotation. This paper presents a control algorithm for a slider-crank WEC. In this study, a time-domain hydrodynamic analysis is adopted, and an AC synchronous machine is used in the power take-off system to achieve relatively high system performance. Also, a rule-based phase control strategy is applied to maximize energy extraction, making the system suitable for not only regular sinusoidal waves but also irregular waves. Simulations are carried out under regular sinusoidal wave and synthetically produced irregular wave conditions; performance validations are also presented with high-precision, real ocean wave surface elevation data. The influences of significant wave height, and peak period upon energy extraction of the system are studied. Energy extraction results using the proposed method are compared to those of the passive loading and complex conjugate control strategies; results show that the level of energy extraction is between those of the passive loading and complex conjugate control strategies, and the suboptimal nature of this control strategy is verified.

  4. Different Predictive Control Strategies for Active Load Management in Distributed Power Systems with High Penetration of Renewable Energy Sources

    DEFF Research Database (Denmark)

    Zong, Yi; Bindner, Henrik W.; Gehrke, Oliver

    2013-01-01

    In order to achieve a Danish energy supply based on 100% renewable energy from combinations of wind, biomass, wave and solar power in 2050 and to cover 50% of the Danish electricity consumption by wind power in 2020, it requires more renewable energy in buildings and industries (e.g. cold stores......, greenhouses, etc.), and to coordinate the management of large numbers of distributed energy resources with the smart grid solution. This paper presents different predictive control (Genetic Algorithm-based and Model Predictive Control-based) strategies that schedule controlled loads in the industrial...... and residential sectors, based on dynamic power price and weather forecast, considering users’ comfort settings to meet an optimization objective, such as maximum profit or minimum energy consumption. Some field tests were carried out on a facility for intelligent, active and distributed power systems, which...

  5. Integrating of renewable energy in operation system: the Special Regime Control Centre (CECRE)

    International Nuclear Information System (INIS)

    Division, M.

    2007-01-01

    The implementation of Red Electrica de Espana Special Regime Control Centre (CECRE) has demonstrated the Spanish System Operators commitment of integrating the maximum possible wind power generation into the electrical system compatible with secure operation. With this leadership initiative,for the first time in the world, a System Operator Control Centre (CECRE) has succeeded in sending power control instructions to wind power generators over the country through Generation Control Centres (CGC) to which these generators must be connected complying with the Spanish Rules. (Author)

  6. Atomic Energy Control Regulations

    International Nuclear Information System (INIS)

    1992-01-01

    This is the consolidated text of the Atomic Energy Control Regulations of 17 March 1960, with amendments to 27 August 1992. The Regulations cover the licensing of nuclear facilities, radiation sources, including uranium mining, radiation protection questions, etc. (NEA)

  7. Model-based predictive control applied to multi-carrier energy systems

    NARCIS (Netherlands)

    Arnold, M.; Negenborn, R.R.; Andersson, G.; De Schutter, B.

    2009-01-01

    The optimal operation of an integrated electricity and natural gas infrastructure is investigated. The couplings between the electricity system and the gas system are modeled by so-called energy hubs, which represent the interface between the loads on the one hand and the transmission

  8. Wisdom Appliance Control System

    Science.gov (United States)

    Hendrick; Jheng, Jyun-Teng; Tsai, Chen-Chai; Liou, Jia-Wei; Wang, Zhi-Hao; Jong, Gwo-Jia

    2017-07-01

    Intelligent appliances wisdom involves security, home care, convenient and energy saving, but the home automation system is still one of the core unit, and also using micro-processing electronics technology to centralized and control the home electrical products and systems, such as: lighting, television, fan, air conditioning, stereo, it composed of front-controller systems and back-controller panels, user using front-controller to control command, and then through the back-controller to powered the device.

  9. Small Wind Energy Systems

    DEFF Research Database (Denmark)

    Simoes, Marcelo; Farret, Felix Alberto; Blaabjerg, Frede

    2015-01-01

    devices, and a centralized distribution control. In order to establish a small wind energy system it is important to observe the following: (i) Attending the energy requirements of the actual or future consumers; (ii) Establishing civil liabilities in case of accidents and financial losses due to shortage...... or low quality of energy; (iii) Negotiating collective conditions to interconnect the microgrid with the public network or with other sources of energy that is independent of wind resources; (iv) Establishing a performance criteria of power quality and reliability to end-users, in order to reduce costs...... and guaranteeing an acceptable energy supply. This paper discuss how performance is affected by local conditions and random nature of the wind, power demand profiles, turbine related factors, and presents the technical issues for implementing a self-excited induction generator system, or a permanent magnet based...

  10. Information and Communications Systems for Control-by-Price of Distributed Energy Resources and Flexible Demand

    OpenAIRE

    Nyeng, Preben; Østergaard, Jacob

    2011-01-01

    The control-by-price concept fits well with controlling small-scale generation, storage and demand. In this paper, we investigate the required information and communications systems that are needed to realize the control-by-price concept for such units. We first present a proposal for overall infrastructure and subsystem design and secondly focus on the design and implementation of the end-user price-responsive controller, interfaces, and communications. The design and its applicability on ex...

  11. A Novel Supercapacitor/Lithium-Ion Hybrid Energy System with a Fuzzy Logic-Controlled Fast Charging and Intelligent Energy Management System

    Directory of Open Access Journals (Sweden)

    Muhammad Adil Khan

    2018-05-01

    Full Text Available The electric powered wheelchair (EPW is an essential assistive tool for people with serious injuries or disability. This manuscript describes the validation of applied research for reducing the charging time of an electric wheelchair using a hybrid electric system (HES composed of a supercapacitor (SC bank and a lithium-ion battery with a fuzzy logic controller (FLC-based fast charging system for Li-ion batteries and a fuzzy logic-based intelligent energy management system (FLIEMS for controlling the power flow within the HES. The fast charging FLC was designed to drive the voltage difference (Vd among the different cells of a multi-cell battery and the cell voltage (Vc of an individual cell. These parameters (voltage difference and cell voltage were used as input voltages to reduce the charge time and activate a bypass equalization (BPE scheme. BPE was introduced in this paper so that the battery operates within the safe voltage range. For SC/Li-ion HES, the FLIEMS presented in this paper controls the bi-directional power flow to smooth the power extracted from Li-ion batteries. Moreover, a dual active bridge isolated bidirectional DC converter (DAB-IBDC was used for power conversion. The DAB-IBDC presented in this paper has the characteristics of galvanic isolation, and high power conversion efficiency compared to the conventional converter circuits due to the reduced reverse power flow and current stresses.

  12. Real-time control and data-acquisition system for high-energy neutral-beam injectors

    International Nuclear Information System (INIS)

    Glad, A.S.; Jacobson, V.

    1981-12-01

    The need for a real-time control system and a data acquisition, processing and archiving system operating in parallel on the same computer became a requirement on General Atomic's Doublet III fusion energy project with the addition of high energy neutral beam injectors. The data acquisition processing and archiving system is driven from external events and is sequenced through each experimental shot utilizing ModComp's intertask message service. This system processes, archives and displays on operator console CRTs all physics diagnostic data related to the neutral beam injectores such as temperature, beam alignment, etc. The real-time control system is data base driven and provides periodic monitoring and control of the numerous dynamic subsystems of the neutral beam injectors such as power supplies, timing, water cooling, etc

  13. A control strategy of hybrid solar-wind energy generation system

    Directory of Open Access Journals (Sweden)

    Sharma Himanshu

    2017-06-01

    Full Text Available Synchronization in the energy generated by renewable energy sources is one of the significant issue associated with the converter used in the system module. The presented paper concentrates on the design aspect of a PV and wind power input to a DC-DC converter which can be practically useful in hybrid renewable energy power systems. In this regard, the proposed converter can be utilized to obtain a smooth regulated output voltage from the given input renewable energy power sources. The proposed converter can be efficiently work under critical conditions having very few ripple in current waveform of input or output. A major advantage with this type of converter is the simple circuit with respect to the conventional converters in some critical situations. At the end, the result based on the simulation exercise and various experiments, performance of the converter in different situations is presented so that the efficiency of the designed converter arrangement is accepted.

  14. Energy storage connection system

    Science.gov (United States)

    Benedict, Eric L.; Borland, Nicholas P.; Dale, Magdelena; Freeman, Belvin; Kite, Kim A.; Petter, Jeffrey K.; Taylor, Brendan F.

    2012-07-03

    A power system for connecting a variable voltage power source, such as a power controller, with a plurality of energy storage devices, at least two of which have a different initial voltage than the output voltage of the variable voltage power source. The power system includes a controller that increases the output voltage of the variable voltage power source. When such output voltage is substantially equal to the initial voltage of a first one of the energy storage devices, the controller sends a signal that causes a switch to connect the variable voltage power source with the first one of the energy storage devices. The controller then causes the output voltage of the variable voltage power source to continue increasing. When the output voltage is substantially equal to the initial voltage of a second one of the energy storage devices, the controller sends a signal that causes a switch to connect the variable voltage power source with the second one of the energy storage devices.

  15. Model Predictive Control of a Wave Energy Converter with Discrete Fluid Power Power Take-Off System

    Directory of Open Access Journals (Sweden)

    Anders Hedegaard Hansen

    2018-03-01

    Full Text Available Wave power extraction algorithms for wave energy converters are normally designed without taking system losses into account leading to suboptimal power extraction. In the current work, a model predictive power extraction algorithm is designed for a discretized power take of system. It is shown how the quantized nature of a discrete fluid power system may be included in a new model predictive control algorithm leading to a significant increase in the harvested power. A detailed investigation of the influence of the prediction horizon and the time step is reported. Furthermore, it is shown how the inclusion of a loss model may increase the energy output. Based on the presented results it is concluded that power extraction algorithms based on model predictive control principles are both feasible and favorable for use in a discrete fluid power power take-off system for point absorber wave energy converters.

  16. Fractional-order control and simulation of wind energy systems with PMSG/full-power converter topology

    International Nuclear Information System (INIS)

    Melicio, R.; Mendes, V.M.F.; Catalao, J.P.S.

    2010-01-01

    This paper presents a new integrated model for the simulation of wind energy systems. The proposed model is more realistic and accurate, considering a variable-speed wind turbine, two-mass rotor, permanent magnet synchronous generator (PMSG), different power converter topologies, and filters. Additionally, a new control strategy is proposed for the variable-speed operation of wind turbines with PMSG/full-power converter topology, based on fractional-order controllers. Comprehensive simulation studies are carried out with matrix and multilevel power converter topologies, in order to adequately assert the system performance in what regards the quality of the energy injected into the electric grid. Finally, conclusions are duly drawn.

  17. Fractional-order control and simulation of wind energy systems with PMSG/full-power converter topology

    Energy Technology Data Exchange (ETDEWEB)

    Melicio, R.; Catalao, J.P.S. [Department of Electromechanical Engineering, University of Beira Interior, R. Fonte do Lameiro, 6201-001 Covilha (Portugal); Mendes, V.M.F. [Department of Electrical Engineering and Automation, Instituto Superior de Engenharia de Lisboa, R. Conselheiro Emidio Navarro, 1950-062 Lisbon (Portugal)

    2010-06-15

    This paper presents a new integrated model for the simulation of wind energy systems. The proposed model is more realistic and accurate, considering a variable-speed wind turbine, two-mass rotor, permanent magnet synchronous generator (PMSG), different power converter topologies, and filters. Additionally, a new control strategy is proposed for the variable-speed operation of wind turbines with PMSG/full-power converter topology, based on fractional-order controllers. Comprehensive simulation studies are carried out with matrix and multilevel power converter topologies, in order to adequately assert the system performance in what regards the quality of the energy injected into the electric grid. Finally, conclusions are duly drawn. (author)

  18. Control of mitochondrial metabolism and systemic energy homeostasis by microRNAs 378 and 378*.

    Science.gov (United States)

    Carrer, Michele; Liu, Ning; Grueter, Chad E; Williams, Andrew H; Frisard, Madlyn I; Hulver, Matthew W; Bassel-Duby, Rhonda; Olson, Eric N

    2012-09-18

    Obesity and metabolic syndrome are associated with mitochondrial dysfunction and deranged regulation of metabolic genes. Peroxisome proliferator-activated receptor γ coactivator 1β (PGC-1β) is a transcriptional coactivator that regulates metabolism and mitochondrial biogenesis through stimulation of nuclear hormone receptors and other transcription factors. We report that the PGC-1β gene encodes two microRNAs (miRNAs), miR-378 and miR-378*, which counterbalance the metabolic actions of PGC-1β. Mice genetically lacking miR-378 and miR-378* are resistant to high-fat diet-induced obesity and exhibit enhanced mitochondrial fatty acid metabolism and elevated oxidative capacity of insulin-target tissues. Among the many targets of these miRNAs, carnitine O-acetyltransferase, a mitochondrial enzyme involved in fatty acid metabolism, and MED13, a component of the Mediator complex that controls nuclear hormone receptor activity, are repressed by miR-378 and miR-378*, respectively, and are elevated in the livers of miR-378/378* KO mice. Consistent with these targets as contributors to the metabolic actions of miR-378 and miR-378*, previous studies have implicated carnitine O-acetyltransferase and MED13 in metabolic syndrome and obesity. Our findings identify miR-378 and miR-378* as integral components of a regulatory circuit that functions under conditions of metabolic stress to control systemic energy homeostasis and the overall oxidative capacity of insulin target tissues. Thus, these miRNAs provide potential targets for pharmacologic intervention in obesity and metabolic syndrome.

  19. A comparative study between three sensorless control strategies for PMSG in wind energy conversion system

    Energy Technology Data Exchange (ETDEWEB)

    Brahmi, Jemaa; Krichen, Lotfi; Ouali, Abderrazak [Advanced Control and Energy Management Research Unit ENIS, Department of Electrical Engineering, University of Sfax, 3038 Sfax (Tunisia)

    2009-09-15

    This paper presents a comparative study of sliding mode, artificial neural network and model reference adaptive speed observers for a speed sensorless permanent magnet synchronous generator (PMSG) in wind energy conversion system (WECS). Wind velocity and position sensorless operating methods for wind generation system using observer are proposed only by measuring phase voltages and currents. Maximum wind energy extraction is achieved by running the wind turbine generator in variable-speed mode. In addition the three speed observers are compared to verify the robustness against parameter variations. (author)

  20. Design and Implementation of Energy Efficiency in HVAC Systems Based on Robust PID Control for Industrial Applications

    Directory of Open Access Journals (Sweden)

    Muharrem Imal

    2015-01-01

    Full Text Available Energy efficiency in heating, ventilating, and air-conditioning (HVAC systems is a primary concern in process projects, since the energy consumption has the highest percentage in HVAC for all processes. Without sacrifice of thermal comfort, to reset the suitable operating parameters, such as the humidity and air temperature, would have energy saving with immediate effect. In this paper, the simulation-optimization approach described the effective energy efficiency for HVAC systems which are used in industrial process. Due to the complex relationship of the HVAC system parameters, it is necessary to suggest optimum settings for different operations in response to the dynamic cooling loads and changing weather conditions during a year. Proportional-integral-derivative (PID programming was developed which can effectively handle the discrete, nonlinear and highly constrained optimization problems. Energy efficiency process has been made by controlling of alternative current (AC drivers for ventilation and exhaust fans, according to supplied air flow capacity and differential air pressure between supplied and exhaust air. Supervisory controller software was developed by using programmable controllers and human machine interface (HMI units. The new designed HVAC control system would have a saving potential of about 40% as compared to the existing operational settings, without any extra cost.

  1. Stochastic Model Predictive Fault Tolerant Control Based on Conditional Value at Risk for Wind Energy Conversion System

    Directory of Open Access Journals (Sweden)

    Yun-Tao Shi

    2018-01-01

    Full Text Available Wind energy has been drawing considerable attention in recent years. However, due to the random nature of wind and high failure rate of wind energy conversion systems (WECSs, how to implement fault-tolerant WECS control is becoming a significant issue. This paper addresses the fault-tolerant control problem of a WECS with a probable actuator fault. A new stochastic model predictive control (SMPC fault-tolerant controller with the Conditional Value at Risk (CVaR objective function is proposed in this paper. First, the Markov jump linear model is used to describe the WECS dynamics, which are affected by many stochastic factors, like the wind. The Markov jump linear model can precisely model the random WECS properties. Second, the scenario-based SMPC is used as the controller to address the control problem of the WECS. With this controller, all the possible realizations of the disturbance in prediction horizon are enumerated by scenario trees so that an uncertain SMPC problem can be transformed into a deterministic model predictive control (MPC problem. Finally, the CVaR object function is adopted to improve the fault-tolerant control performance of the SMPC controller. CVaR can provide a balance between the performance and random failure risks of the system. The Min-Max performance index is introduced to compare the fault-tolerant control performance with the proposed controller. The comparison results show that the proposed method has better fault-tolerant control performance.

  2. Preventing Control Constraint Violations by Use of Energy Balances for a Class of Coupled Systems: Applied to a Power Plant

    DEFF Research Database (Denmark)

    Odgaard, Peter Fogh; Stoustrup, Jakob

    2007-01-01

    recomputes the reference values to the system such that control signal constraint violations are avoided. The new reference values are found using an energy balance of the system. The scheme is intended to handle rarely occurring constraint violations, so the only concern is that the system should be stable...... and not to optimize performance during all conditions. The scheme is applied to an example with a coal mill pulverizing coal for a power plant.  ...

  3. Reducing the energy consumption of an earth–air heat exchanger with a PID control system

    International Nuclear Information System (INIS)

    Diaz-Mendez, S.E.; Patiño-Carachure, C.; Herrera-Castillo, J.A.

    2014-01-01

    Highlights: • The application of control actions to green technologies has been simulated. • Energy consumption of green technologies can be reduced even more. • The efficiency of green technologies can be raised. • Environmental concerns can be diminished. • The sustainability of the planet can be increased. - Abstract: Reducing environmental emissions is one of the challenges that human being has to overcome. It can only be reached with a proper energetic efficiency and management of the processes that exist in the society nowadays. Several academic works have mentioned that raising the efficiency of a process it also increases sustainability and in turn decreases the environmental impact. One process that requires much attention is the cooling and heating of buildings; this process contributes to the major part of the electric bill, in particular, if a conventional and old air conditioning is used as commonly occurs in many countries. In recent years there have been developed new alternatives that are used in few countries, such as the earth–air heat exchanger, where air is passed through a heat exchanger buried a few meters below the ground. The heat exchanger takes advantage of the well-known difference between the temperature of the surrounding air and the temperature of the ground for cooling or heating the air that is subsequently injected into the buildings. This process requires less energy, then in the present work is thought that a PID (Proportional, Integral and Derivative) controller can be applied to an earth–air heat exchanger to reduce even more the energy consumption. Therefore, a simulation of a thermodynamic model of an earth–air heat exchanger was done and used along with a PID controller, to estimate savings in energy consumption. The results show that the energy consumption can be reduced up to 87% with the PID control, hence the efficiency of the process is increased as well as the sustainability of the planet and thus the

  4. Adaptive control paradigm for photovoltaic and solid oxide fuel cell in a grid-integrated hybrid renewable energy system

    Science.gov (United States)

    Khan, Laiq

    2017-01-01

    The hybrid power system (HPS) is an emerging power generation scheme due to the plentiful availability of renewable energy sources. Renewable energy sources are characterized as highly intermittent in nature due to meteorological conditions, while the domestic load also behaves in a quite uncertain manner. In this scenario, to maintain the balance between generation and load, the development of an intelligent and adaptive control algorithm has preoccupied power engineers and researchers. This paper proposes a Hermite wavelet embedded NeuroFuzzy indirect adaptive MPPT (maximum power point tracking) control of photovoltaic (PV) systems to extract maximum power and a Hermite wavelet incorporated NeuroFuzzy indirect adaptive control of Solid Oxide Fuel Cells (SOFC) to obtain a swift response in a grid-connected hybrid power system. A comprehensive simulation testbed for a grid-connected hybrid power system (wind turbine, PV cells, SOFC, electrolyzer, battery storage system, supercapacitor (SC), micro-turbine (MT) and domestic load) is developed in Matlab/Simulink. The robustness and superiority of the proposed indirect adaptive control paradigm are evaluated through simulation results in a grid-connected hybrid power system testbed by comparison with a conventional PI (proportional and integral) control system. The simulation results verify the effectiveness of the proposed control paradigm. PMID:28329015

  5. Adaptive control paradigm for photovoltaic and solid oxide fuel cell in a grid-integrated hybrid renewable energy system.

    Science.gov (United States)

    Mumtaz, Sidra; Khan, Laiq

    2017-01-01

    The hybrid power system (HPS) is an emerging power generation scheme due to the plentiful availability of renewable energy sources. Renewable energy sources are characterized as highly intermittent in nature due to meteorological conditions, while the domestic load also behaves in a quite uncertain manner. In this scenario, to maintain the balance between generation and load, the development of an intelligent and adaptive control algorithm has preoccupied power engineers and researchers. This paper proposes a Hermite wavelet embedded NeuroFuzzy indirect adaptive MPPT (maximum power point tracking) control of photovoltaic (PV) systems to extract maximum power and a Hermite wavelet incorporated NeuroFuzzy indirect adaptive control of Solid Oxide Fuel Cells (SOFC) to obtain a swift response in a grid-connected hybrid power system. A comprehensive simulation testbed for a grid-connected hybrid power system (wind turbine, PV cells, SOFC, electrolyzer, battery storage system, supercapacitor (SC), micro-turbine (MT) and domestic load) is developed in Matlab/Simulink. The robustness and superiority of the proposed indirect adaptive control paradigm are evaluated through simulation results in a grid-connected hybrid power system testbed by comparison with a conventional PI (proportional and integral) control system. The simulation results verify the effectiveness of the proposed control paradigm.

  6. Control of a Stand-Alone Variable Speed Wind Energy Supply System

    Directory of Open Access Journals (Sweden)

    Mohamed M. Hamada

    2013-04-01

    Full Text Available This paper presents a simple control strategy for the operation of a variable speed stand-alone wind turbine with a permanent magnet synchronous generator (PMSG. The PMSG is connected to a three phase resistive load through a switch mode rectifier and a voltage source inverter. Control of the generator side converter is used to achieve maximum power extraction from the available wind power. Control of the DC-DC bidirectional buck-boost converter, which is connected between batteries bank and DC-link voltage, is used to maintain the DC-link voltage at a constant value. It is also used to make the batteries bank stores the surplus of wind energy and supplies this energy to the load during a wind power shortage. The load side voltage source inverter uses a relatively complex vector control scheme to control the output load voltage in terms of amplitude and frequency. The control strategy works under wind speed variation as well as with variable load. Extensive simulation results have been performed using MATLAB/SIMULINK.

  7. Primary Frequency Regulation with Li-Ion Battery Energy Storage System - Evaluation and Comparison of Different Control Strategies

    DEFF Research Database (Denmark)

    Thorbergsson, Egill; Knap, Vaclav; Swierczynski, Maciej Jozef

    2013-01-01

    devices is becoming more attractive, the aim of this paper is to analyse the viability of providing primary frequency regulation with Lithium-ion based energy storage systems. Three control strategies of the energy storage system are analysed and compared in terms of economic benefits on the Danish energy...... market. The revenues and degradation of the Lithium-ion batteries are obtained by simulations. Furthermore, an energy management strategy based on variable state-of-charge (SOC) set-point is evaluated. Preliminary, the influence of different state-of-charge levels on the cycle lifetime is estimated......The increased grid penetration levels of renewable sources are at the expense of the conventional power plants. This means that the grid support functions, traditionally achieved by the conventional power plants, need to be provided by new technologies. Since grid support with energy storage...

  8. Study on the application of NASA energy management techniques for control of a terrestrial solar water heating system

    Science.gov (United States)

    Swanson, T. D.; Ollendorf, S.

    1979-01-01

    This paper addresses the potential for enhanced solar system performance through sophisticated control of the collector loop flow rate. Computer simulations utilizing the TRNSYS solar energy program were performed to study the relative effect on system performance of eight specific control algorithms. Six of these control algorithms are of the proportional type: two are concave exponentials, two are simple linear functions, and two are convex exponentials. These six functions are typical of what might be expected from future, more advanced, controllers. The other two algorithms are of the on/off type and are thus typical of existing control devices. Results of extensive computer simulations utilizing actual weather data indicate that proportional control does not significantly improve system performance. However, it is shown that thermal stratification in the liquid storage tank may significantly improve performance.

  9. Simulation models developed for voltage control in a distribution network using energy storage systems for PV penetration

    DEFF Research Database (Denmark)

    Mihet-Popa, Lucian; Bindner, Henrik W.

    2013-01-01

    This paper presents the development of simulation models for DER components in a distribution network, with focus on voltage controllers using energy storage systems for PV penetration. The Vanadium Redox Battery (VRB) system model, used as an energy storage system, was implemented in MATLAB....../Simulink and DIgSILENT PowerFactory, based on the efficiency of different components-such as: cell stacks, electrolytes, pumps and power converters, whilst power losses were also taken into account. The simulation results have been validated against measurements using experimental facility of a distributed power...

  10. Control mechanisms for battery energy storage system performing primary frequency regulation and self-consumption optimization

    NARCIS (Netherlands)

    Pliatskas Stylianidis, A.

    2016-01-01

    This report contains the design of a model for the integration of a battery energy system in a household level and its use for primary frequency regulation and self-consumption optimization. The main goal of this project was to investigate what are the possible applications and the most suitable for

  11. Thirteenth symposium on energy engineering sciences: Proceedings. Fluid/thermal processes, systems analysis and control

    International Nuclear Information System (INIS)

    1995-01-01

    The DOE Office of Basic Energy Sciences, of which Engineering Research is a component program, is responsible for the long-term mission-oriented research in the Department. Consistent with the DOE/BES mission, the Engineering Research Program is charged with the identification, initiation, and management of fundamental research on broad, generic topics addressing energy-related engineering problems. Its stated goals are: (1) to improve and extend the body of knowledge underlying current engineering practice so as to create new options for enhancing energy savings and production, for prolonging useful life of energy-related structures and equipment, and for developing advanced manufacturing technologies and materials processing with emphasis on reducing costs with improved industrial production and performance quality; and (2) to expand the store of fundamental concepts for solving anticipated and unforeseen engineering problems in the energy technologies. The meeting covered the following areas: (1) fluid mechanics 1--fundamental properties; (2) fluid mechanics 2--two phase flow; (3) thermal processes; (4) fluid mechanics 3; (5) process analysis and control; (6) fluid mechanics 4--turbulence; (7) fluid mechanics 5--chaos; (8) materials issues; and (9) plasma processes. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database

  12. Thirteenth symposium on energy engineering sciences: Proceedings. Fluid/thermal processes, systems analysis and control

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-11-01

    The DOE Office of Basic Energy Sciences, of which Engineering Research is a component program, is responsible for the long-term mission-oriented research in the Department. Consistent with the DOE/BES mission, the Engineering Research Program is charged with the identification, initiation, and management of fundamental research on broad, generic topics addressing energy-related engineering problems. Its stated goals are: (1) to improve and extend the body of knowledge underlying current engineering practice so as to create new options for enhancing energy savings and production, for prolonging useful life of energy-related structures and equipment, and for developing advanced manufacturing technologies and materials processing with emphasis on reducing costs with improved industrial production and performance quality; and (2) to expand the store of fundamental concepts for solving anticipated and unforeseen engineering problems in the energy technologies. The meeting covered the following areas: (1) fluid mechanics 1--fundamental properties; (2) fluid mechanics 2--two phase flow; (3) thermal processes; (4) fluid mechanics 3; (5) process analysis and control; (6) fluid mechanics 4--turbulence; (7) fluid mechanics 5--chaos; (8) materials issues; and (9) plasma processes. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database.

  13. The Csr System Regulates Escherichia coli Fitness by Controlling Glycogen Accumulation and Energy Levels

    Directory of Open Access Journals (Sweden)

    Manon Morin

    2017-10-01

    Full Text Available In the bacterium Escherichia coli, the posttranscriptional regulatory system Csr was postulated to influence the transition from glycolysis to gluconeogenesis. Here, we explored the role of the Csr system in the glucose-acetate transition as a model of the glycolysis-to-gluconeogenesis switch. Mutations in the Csr system influence the reorganization of gene expression after glucose exhaustion and disturb the timing of acetate reconsumption after glucose exhaustion. Analysis of metabolite concentrations during the transition revealed that the Csr system has a major effect on the energy levels of the cells after glucose exhaustion. This influence was demonstrated to result directly from the effect of the Csr system on glycogen accumulation. Mutation in glycogen metabolism was also demonstrated to hinder metabolic adaptation after glucose exhaustion because of insufficient energy. This work explains how the Csr system influences E. coli fitness during the glycolysis-gluconeogenesis switch and demonstrates the role of glycogen in maintenance of the energy charge during metabolic adaptation.

  14. Energy control and sustainable development

    International Nuclear Information System (INIS)

    2002-01-01

    The contributions are dealing with the different aspects of energy control: key figures of the world consumption, evolution perspectives (energy control and energy demand in middle- and long-term world scenarios, global challenges, European perspectives, energy control in public decision in France, the new French energy accounting), regional differences (energy control in the United States, Russia, China, India, Brazil, West Africa, Mediterranean Sea), energy control and society (electricity privatisation in Salvador, regulatory approach or voluntary agreements for domestic appliances, comparison of energy control and renewable energies in France, complex accounting for energy demand control in a consumption society)

  15. The Csr System Regulates Escherichia coli Fitness by Controlling Glycogen Accumulation and Energy Levels.

    Science.gov (United States)

    Morin, Manon; Ropers, Delphine; Cinquemani, Eugenio; Portais, Jean-Charles; Enjalbert, Brice; Cocaign-Bousquet, Muriel

    2017-10-31

    In the bacterium Escherichia coli , the posttranscriptional regulatory system Csr was postulated to influence the transition from glycolysis to gluconeogenesis. Here, we explored the role of the Csr system in the glucose-acetate transition as a model of the glycolysis-to-gluconeogenesis switch. Mutations in the Csr system influence the reorganization of gene expression after glucose exhaustion and disturb the timing of acetate reconsumption after glucose exhaustion. Analysis of metabolite concentrations during the transition revealed that the Csr system has a major effect on the energy levels of the cells after glucose exhaustion. This influence was demonstrated to result directly from the effect of the Csr system on glycogen accumulation. Mutation in glycogen metabolism was also demonstrated to hinder metabolic adaptation after glucose exhaustion because of insufficient energy. This work explains how the Csr system influences E. coli fitness during the glycolysis-gluconeogenesis switch and demonstrates the role of glycogen in maintenance of the energy charge during metabolic adaptation. IMPORTANCE Glycogen is a polysaccharide and the main storage form of glucose from bacteria such as Escherichia coli to yeasts and mammals. Although its function as a sugar reserve in mammals is well documented, the role of glycogen in bacteria is not as clear. By studying the role of posttranscriptional regulation during metabolic adaptation, for the first time, we demonstrate the role of sugar reserve played by glycogen in E. coli Indeed, glycogen not only makes it possible to maintain sufficient energy during metabolic transitions but is also the key component in the capacity of cells to resume growth. Since the essential posttranscriptional regulatory system Csr is a major regulator of glycogen accumulation, this work also sheds light on the central role of posttranscriptional regulation in metabolic adaptation. Copyright © 2017 Morin et al.

  16. Selection of Non-Restorable Reserved Energy Process Control and Management Systems

    Directory of Open Access Journals (Sweden)

    V. A. Anischenko

    2012-01-01

    Full Text Available The paper considers problems pertaining to selection of non-restorable continuously reserved discrete control and management systems of electric and heat and power processes. Two problems concerning system optimization on the basis of the following criteria – their reliability and cost have been solved in the paper. 

  17. Intelligent energy management control for independent microgrid

    Indian Academy of Sciences (India)

    Energy management control; multi-agent system; microgrid; energy forecast; hybrid power ... power to the local load most of the time in this energy management strategy. ... Electrical and Electronics Engineering Department, PSG College of ...

  18. Energy Systems Integration News | Energy Systems Integration Facility |

    Science.gov (United States)

    organization and independent system operator settle energy transactions in its real-time markets at the same time interval it dispatches energy, and settle operating reserves transactions in its real-time markets the electric grid. These control systems will enable real-time coordination between distributed energy

  19. Control system of test and research facilities for nuclear energy industry

    International Nuclear Information System (INIS)

    1983-01-01

    IHI manufactures several kinds of test and research facilities used for research and development of new type power reactor and solidification system of high level radioactive liquid waste and safety research of light water reactor. These facilities are usually new type plants themselves, so that their control systems have to be designed individually for each plant with the basic conception. They have many operation modes because of their purposes of research and development, so the operation has to be automatized and requires the complicated sequence control system. In addition to these requirements, the detail design is hardly fixed on schedule and often modified during the initial start up period. Therefore, the computer control system was applied to these facilities with CRT display for man-machine communication earlier than to commercial power plants, because in the computer system the control logic is not hard wired but soft programmed and can be easily modified. In this paper, two typical computer control systems, one for PWR reflood test facility and another for mock-up test facility for solidification of liquid waste, are introduced. (author)

  20. Information and Communications Systems for Control-by-Price of Distributed Energy Resources and Flexible Demand

    DEFF Research Database (Denmark)

    Nyeng, Preben; Østergaard, Jacob

    2011-01-01

    infrastructure and subsystem design and secondly focus on the design and implementation of the end-user price-responsive controller, interfaces, and communications. The design and its applicability on existing devices is verified through laboratory tests with two cases: electric space heating thermostat control...... and a small combined heat and power unit. The results show that the price-responsive controller reduces the end user’s electricity cost, or increases his income respectively, by about 7%. At the same time, the price-responsive controller provides an interface for the transmission system operator to utilize...

  1. Energy Systems Integration News - October 2016 | Energy Systems Integration

    Science.gov (United States)

    Facility | NREL October 2016 Energy Systems Integration News A monthly recap of the latest energy systems integration (ESI) developments at NREL and around the world. Subscribe Archives October Integration Facility's main control room. OMNETRIC Group Demonstrates a Distributed Control Hierarchy for

  2. Selection and Implementation of Single Building EMCS (Energy Monitoring and Control Systems).

    Science.gov (United States)

    1983-08-01

    Setpoint Night Setback 161 Figure 20: Dual Setpoint Night Setback/up 162 Figure 21: Centrifugal Chiller Reset 166 Figure 22: Centrifugal Chiller Capacity...Program outputs. Hot water temperature. Application notes. A dedicated local loop controller may be implemented. Chiller optimization . The chiller ... optimization program can be implemented in chilled water plants with multiple chillers . Based on chiller operating data and the energy input requirements

  3. Implementation of the fuzzy theory in control of alternative energy generation system; Aplicacao da teoria fuzzy no controle de sistemas de geracao de energias alternativas

    Energy Technology Data Exchange (ETDEWEB)

    Caneppele, Fernando de Lima [Universidade Estadual Paulista (FCA/UNESP), Botucatu, SP (Brazil). Fac. de Ciencias Agronomicas. Curso de Pos-Graduacao em Energia na Agricultura], E-mail: fernando@itapeva.unesp.br; Seraphim, Odivaldo Jose [Universidade Estadual Paulista (FCA/UNESP), Botucatu, SP (Brazil). Fac. de Ciencias Agronomicas. Dept. de Engenharia Rural], E-mail: seraphim@fca.unesp.br

    2010-07-01

    This paper presents the application and use of a methodology based on fuzzy theory and simulates its use in intelligent control of a hybrid system for generating electricity, using solar energy, photovoltaic and wind. When using a fuzzy control system, it reached the point of maximum generation of energy, thus shifting all energy generated from the alternative sources-solar photovoltaic and wind, cargo and / or batteries when its use not immediately. The model uses three variables used for entry, which are: wind speed, solar radiation and loading the bank of batteries. For output variable has to choose which of the batteries of the battery bank is charged. For the simulations of this work is used MATLAB software. In this environment mathematical computational are analyzed and simulated all mathematical modeling, rules and other variables in the system described fuzzy. This model can be used in a system of control of hybrid systems for generating energy, providing the best use of energy sources, sun and wind, so we can extract the maximum energy possible these alternative sources without any prejudice to the environment. (author)

  4. Energy Information Systems

    Science.gov (United States)

    Home > Building Energy Information Systems and Performance Monitoring (EIS-PM) Building Energy evaluate and improve performance monitoring tools for energy savings in commercial buildings. Within the and visualization capabilities to energy and facility managers. As an increasing number of

  5. Applications and Energy Consumption of Demand Controlled Ventilation Systems. Modelling, Simulation and Implementation of Modular Built Dynamical VAV Systems and Control Strategies

    Energy Technology Data Exchange (ETDEWEB)

    Soerensen, Bjoern R.

    2002-07-01

    This thesis discusses many topics of heating and ventilation. This is because the ventilation system is an integrated part of its host building. The functionality and effectiveness of the ventilation system are very much dependent on the building's architectural design, its internal materials, its occupants, its air tightness characteristics and its placement in the terrain. Although this thesis emphasizes strongly on VAV (Variable Air Volume) systems and, in particular, modelling and simulation of such systems, it touches a range of important HVAC related issues. The scope is however, limited to the field of comfort ventilation. That is because ventilation in industrial environments often is subject to separate regulations, and requires other and specialized methods of design and evaluation of ventilation performance. The main objectives have been to: (1) Develop mathematical models for VAV components and systems. (2) Evaluate existing and develop new strategies for VAV demand controlled ventilation by system simulation. (3) Investigate the potential for saving energy and the impact on indoor climate. The development of mathematical models and simulation of VAV systems are given quite much attention compared to the other topics discussed.

  6. Real-Time Dynamic Simulation of Korean Power Grid for Frequency Regulation Control by MW Battery Energy Storage System

    Directory of Open Access Journals (Sweden)

    Tae-Hwan Jin

    2016-12-01

    Full Text Available The aim of this study was to develop a real-time dynamic simulator of a power grid with power plant and battery model. The simulator was used to investigate the frequency control characteristics of a megawatt-scale high-capacity energy storage system connected to the electric power grid. In this study, a lithium-ion secondary battery was chosen as one of the batteries for a grid-connected model. The dynamics of the model was analysed in both steady and transient states. The frequency control system of the battery model plays a role in regulating the grid frequency by controlling the power of energy storage systems according to process variables and grid frequencies. The power grid model based on the current power network of South Korea, included power plants, substations and power demands. The power supply is classified by the type of turbine generator as thermal, nuclear, hydro power, pumped power storage, combined power plants, and batteries, including high-capacity energy storage systems rated for a maximum of 500 MW. This study deals with an installed capacity of 87.17 GW and peak load of 77.30 GW in the Korean power grid. For 24 hours of operation, the maximum and minimum power outputs were simulated as 61.59 GW and 46.32 GW, respectively. The commercialized real-time dynamic simulation software ProTRAX was used. The simulation was conducted to observe the operation characteristics of the frequency control system during a breakdown of power plants, as well as under governor-free operation, auto generation control operation, and with the battery energy storage system connected. The results show that the model is valid for each power plant breakdown simulation. They also confirm that the output power and frequency controls of the battery operated well during simulations.

  7. Control and automation systems

    International Nuclear Information System (INIS)

    Schmidt, R.; Zillich, H.

    1986-01-01

    A survey is given of the development of control and automation systems for energy uses. General remarks about control and automation schemes are followed by a description of modern process control systems along with process control processes as such. After discussing the particular process control requirements of nuclear power plants the paper deals with the reliability and availability of process control systems and refers to computerized simulation processes. The subsequent paragraphs are dedicated to descriptions of the operating floor, ergonomic conditions, existing systems, flue gas desulfurization systems, the electromagnetic influences on digital circuits as well as of light wave uses. (HAG) [de

  8. Coordinated Control Scheme of Battery Energy Storage System (BESS) and Distributed Generations (DGs) for Electric Distribution Grid Operation

    DEFF Research Database (Denmark)

    Cha, Seung-Tae; Zhao, Haoran; Wu, Qiuwei

    2012-01-01

    into the islanding operation mode, while the centralized joint load frequency control (CJLFC) utilizing DGs handles the secondary frequency regulation. The BESS with the associated controllers has been modelled in Real-time digital simulator (RTDS) in order to identify the improvement of the frequency and voltage......This paper describes a coordinated control scheme of battery energy storage system (BESS) and distributed generations (DGs) for electric distribution grid operation. The BESS is designed to stabilize frequency and voltages as a primary control after the electric distribution system enters...... response. The modified IEEE 9-bus system, which is comprised of several DG units, wind power plant and the BESS, has been employed to illustrate the performance of the proposed coordinated flexible control scheme using RTDS in order to verify its practical efficacy....

  9. Incorporating fan control into air-conditioning systems to improve energy efficiency and transient response

    International Nuclear Information System (INIS)

    Yeh, T.-J.; Chen, Yun-Jih; Hwang, Wei-Yang; Lin, Jin-Long

    2009-01-01

    Modern air-conditioners frequently incorporate variable-speed compressors and variable-opening expansion valves with feedback control to improve performance and power efficiency. Because making the fan speeds adjustable adds flexibility to the control design and thus can lead to further improvements in performance and efficiency, this paper proposes two control algorithms, respectively, incorporating the outdoor fan and the indoor fan as the additional control inputs for air-conditioning systems. Both of the control algorithms are designed based on a low-order, linear model obtained from system identification. The first algorithm, which modulates the outdoor fan speed, can reduce the steady state power consumption if the temperature difference between the condenser and the outdoor environment is controlled properly. The second algorithm, which adds one more degree of freedom to control by modulating the indoor fan speed, can improve the transient response because actuator saturations become less likely to occur. The two control algorithms are implemented on a split-type residential air-conditioner and their respective performance is validated experimentally.

  10. A Distributed Control Strategy Based on DC Bus Signaling for Modular Photovoltaic Generation Systems With Battery Energy Storage

    DEFF Research Database (Denmark)

    Sun, Kai; Zhang, Li; Xing, Yan

    2011-01-01

    on improved dc bus signaling is proposed for a modular photovoltaic (PV) generation system with battery energy storage elements. In this paper, the modular PV generation system is composed of three modular dc/dc converters for PV arrays, two grid-connected dc/ac converters, and one dc/dc converter for battery......, grid-connected inversion, and islanding with constant voltage (CV) generation.The power balance of the system under extreme conditions such as the islanding operation with a full-charged battery is taken into account in this control strategy. The dc bus voltage level is employed as an information......Modular generation system, which consists of modular power conditioning converters, is an effective solution to integrate renewable energy sources with conventional utility grid to improve reliability and efficiency, especially for photovoltaic generation. A distributed control strategy based...

  11. Range of expert system for control, modeling and safely operation in nuclear energy

    International Nuclear Information System (INIS)

    Gorlin, A.; Semenov, S.

    1990-01-01

    The paper describes expert system projects which had been developed formerly and are under the development now in NVIIAES Institute, Moscow. One of the accomplished systems (PEX) is a ES-shell of classical type able to manipulate fuzzy expert assessments. The system is used as a shell for ES-advisor for MCP failures diagnostics and in some applications of the same sort. Another realized system (EDES) is on-line express-diagnostical ES for NPP unit emergency regimes identification. EDES is implemented now as a component of NPP system of control and operation conditions diagnostics. Both systems are realized on conventional programming languages Pascal and C, respectively. The presentation describes current developments in ES as well, including classification system for material researches, the project of training ES for second circuit diagnostics based on event tree generating and expert planner for neutron-physical three-dimensional reactor calculations. All this projects are implemented on different versions of PROLOG programming language

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

    DEFF Research Database (Denmark)

    Yang, Yongheng; Koutroulis, Eftichios; Sangwongwanich, Ariya

    2015-01-01

    . An increase of the inverter lifetime and a reduction of the energy yield can alter the cost of energy, demanding an optimization of the power limitation. Therefore, aiming at minimizing the Levelized Cost of Energy (LCOE), the power limit is optimized for the AAPC strategy in this paper. The optimization...... control strategy, the Absolute Active Power Control (AAPC) can effectively solve the overloading issues by limiting the maximum possible PV power to a certain level (i.e., the power limitation), and also benefit the inverter reliability. However, its feasibility is challenged by the energy loss......, compared to the conventional PV inverter operating only in the maximum power point tracking mode. In the presented case study, the minimum of LCOE is achieved for the system when the power limit is optimized to a certain level of the designed maximum feed-in power (i.e., 3 kW). In addition, the proposed...

  13. Multivariable H{sub 2} and H{infinity} control for a wind energy conversion system - a comparison

    Energy Technology Data Exchange (ETDEWEB)

    Rocha, Ronilson; Coutinho, Gilmar Alves; Ferreira, Alexandre Jose; Torga, Flavio Allison [Universidade Federal de Ouro Preto (EM/DECAT/UFOP), MG (Brazil). Escola de Minas. Dept. de Engenharia de Controle e Automacao e de Tecnicas Fundamentais], Emails: rocha@em.ufop.br, gacoutinho@gmail.com, aleengaut@yahoo.com.br, torgautomacao@yahoo.com.br

    2010-10-15

    The Wind Energy Conversion System (WECS) is a nonlinear system, highly dependent on a stochastic variable characterized by sudden variations, and subjected to cyclical disturbances caused by operational phenomena. Thus, the quality of a WECS controller is measured by its capacity to deal with unmodeled dynamics, stochastic signals, and periodic, as well as non-periodic disturbances. Since the WECS' objectives can be easily specified in terms of maximum allowable gain in the disturbance-to-output transfer functions, H2 and H{infinity} methodologies can be good options for designing a WECS stabilizing controller, combining specifications such as: disturbance attenuation, asymptotic tracking, bandwidth limitation, robust stability, and trade-off between performance and control effort. Designs for WECS multivariable feedback controllers based on H2 and H{infinity} methodologies are presented in this paper. The performances of both controllers are computationally simulated, analyzed and compared in order to identify the advantages and drawbacks of each controller design. (author)

  14. Modelica-based Modeling and Simulation to Support Research and Development in Building Energy and Control Systems

    Energy Technology Data Exchange (ETDEWEB)

    Wetter, Michael

    2009-02-12

    Traditional building simulation programs possess attributes that make them difficult to use for the design and analysis of building energy and control systems and for the support of model-based research and development of systems that may not already be implemented in these programs. This article presents characteristic features of such applications, and it shows how equation-based object-oriented modelling can meet requirements that arise in such applications. Next, the implementation of an open-source component model library for building energy systems is presented. The library has been developed using the equation-based object-oriented Modelica modelling language. Technical challenges of modelling and simulating such systems are discussed. Research needs are presented to make this technology accessible to user groups that have more stringent requirements with respect to the numerical robustness of simulation than a research community may have. Two examples are presented in which models from the here described library were used. The first example describes the design of a controller for a nonlinear model of a heating coil using model reduction and frequency domain analysis. The second example describes the tuning of control parameters for a static pressure reset controller of a variable air volume flow system. The tuning has been done by solving a non-convex optimization problem that minimizes fan energy subject to state constraints.

  15. A robust control strategy for mitigating renewable energy fluctuations in a real hybrid power system combined with SMES

    Science.gov (United States)

    Magdy, G.; Shabib, G.; Elbaset, Adel A.; Qudaih, Yaser; Mitani, Yasunori

    2018-05-01

    Utilizing Renewable Energy Sources (RESs) is attracting great attention as a solution to future energy shortages. However, the irregular nature of RESs and random load deviations cause a large frequency and voltage fluctuations. Therefore, in order to benefit from a maximum capacity of the RESs, a robust mitigation strategy of power fluctuations from RESs must be applied. Hence, this paper proposes a design of Load Frequency Control (LFC) coordinated with Superconducting Magnetic Energy Storage (SMES) technology (i.e., an auxiliary LFC), using an optimal PID controller-based Particle Swarm Optimization (PSO) in the Egyptian Power System (EPS) considering high penetration of Photovoltaics (PV) power generation. Thus, from the perspective of LFC, the robust control strategy is proposed to maintain the nominal system frequency and mitigating the power fluctuations from RESs against all disturbances sources for the EPS with the multi-source environment. The EPS is decomposed into three dynamics subsystems, which are non-reheat, reheat and hydro power plants taking into consideration the system nonlinearity. The results by nonlinear simulation Matlab/Simulink for the EPS combined with SMES system considering PV solar power approves that, the proposed control strategy achieves a robust stability by reducing transient time, minimizing the frequency deviations, maintaining the system frequency, preventing conventional generators from exceeding their power ratings during load disturbances, and mitigating the power fluctuations from the RESs.

  16. Security of supply, energy spillage control and peaking options within a 100% renewable electricity system for New Zealand

    International Nuclear Information System (INIS)

    Mason, I.G.; Page, S.C.; Williamson, A.G.

    2013-01-01

    In this paper, issues of security of supply, energy spillage control, and peaking options, within a fully renewable electricity system, are addressed. We show that a generation mix comprising 49% hydro, 23% wind, 13% geothermal, 14% pumped hydro energy storage peaking plant, and 1% biomass-fuelled generation on an installed capacity basis, was capable of ensuring security of supply over an historic 6-year period, which included the driest hydrological year on record in New Zealand since 1931. Hydro spillage was minimised, or eliminated, by curtailing a proportion of geothermal generation. Wind spillage was substantially reduced by utilising surplus generation for peaking purposes, resulting in up to 99.8% utilisation of wind energy. Peaking requirements were satisfied using 1550 MW of pumped hydro energy storage generation, with a capacity factor of 0.76% and an upper reservoir storage equivalent to 8% of existing hydro storage capacity. It is proposed that alternative peaking options, including biomass-fuelled gas turbines and demand-side measures, should be considered. As a transitional policy, the use of fossil-gas–fuelled gas turbines for peaking would result in a 99.8% renewable system on an energy basis. Further research into whether a market-based system is capable of delivering such a renewable electricity system is suggested. - Highlights: • A 100% renewable electricity system was modelled over a 6-year period. • Security of supply was demonstrated, including for the driest year since 1931. • Stored energy spillage was controlled by using flexible base-load generation. • Wind energy utilisation of 99.8% was obtained. • Transitional use of fossil gas for peaking resulted in a 99.8% renewable system

  17. Neural Network based Control of SG based Standalone Generating System with Energy Storage for Power Quality Enhancement

    Science.gov (United States)

    Nayar, Priya; Singh, Bhim; Mishra, Sukumar

    2017-08-01

    An artificial intelligence based control algorithm is used in solving power quality problems of a diesel engine driven synchronous generator with automatic voltage regulator and governor based standalone system. A voltage source converter integrated with a battery energy storage system is employed to mitigate the power quality problems. An adaptive neural network based signed regressor control algorithm is used for the estimation of the fundamental component of load currents for control of a standalone system with load leveling as an integral feature. The developed model of the system performs accurately under varying load conditions and provides good dynamic response to the step changes in loads. The real time performance is achieved using MATLAB along with simulink/simpower system toolboxes and results adhere to an IEEE-519 standard for power quality enhancement.

  18. Potential Energy Flexibility for a Hot-Water Based Heating System in Smart Buildings Via Economic Model Predictive Control

    DEFF Research Database (Denmark)

    Ahmed, Awadelrahman M. A.; Zong, Yi; Mihet-Popa, Lucian

    2017-01-01

    This paper studies the potential of shifting the heating energy consumption in a residential building to low price periods based on varying electricity price signals suing Economic Model Predictive Control strategy. The investigated heating system consists of a heat pump incorporated with a hot...... water tank as active thermal energy storage, where two optimization problems are integrated together to optimize both the heat pump electricity consumption and the building heating consumption. A sensitivity analysis for the system flexibility is examined. The results revealed that the proposed...

  19. Response analysis and energy transmissibility of a vibration isolation system with real-power nonlinearities under a NMPPF controller

    International Nuclear Information System (INIS)

    Huang, Dongmei; Xu, Wei; Shi, Lingling

    2016-01-01

    Highlights: • The nonlinear modified positive position feedback (NMPPF) scheme and the real-power form of restoring and damping forces are combined to improve the response performance of a vibration isolation system. • The primary resonance, dynamical stability and energy transmissibility of the real-power vibration isolation system are studied. • The sensitivity of the controller parameters on the responses has been analyzed. • In order to suppress the amplitude peak, the feedback parameters have been determined by the frequency response. • The energy transmissibility is investigated. - Abstract: In this paper, the nonlinear modified positive position feedback (NMPPF) scheme and the real-power form of restoring and damping forces are combined to improve the response performance of a vibration isolation system. Based on the method of multiple scales, the frequency response, the stability and the energy transmissibility of the real-power vibration isolation system are studied. It is found that the controlled isolation system exhibits a softening behavior for sub-linear restoring force, while it exhibits the two peak response characteristic rather than a hardening behavior for over-linear restoring force. Further, the sensitivity of the feedback parameters on the responses is discussed. The results, compared to the conventional PPF and IRC methods, show that the proposed method is significantly more effective in controlling the steady-state response, and slightly advantageous for the steady-state dynamics control. The effectiveness of this method is also verified by time domain analysis. Then, the suitable feedback and controller parameters are derived by simulation results in which the amplitude peak is suppressed and the resonance stability is maintained. Finally, the energy transmissibility of the vibration isolation system is investigated. The results show that the feedback gain can reduce the whole transmissibility level and greatly suppress vibration

  20. Impact of the duct static pressure reset control strategy on the energy consumption by the HVAC system

    Directory of Open Access Journals (Sweden)

    Walaszczyk Juliusz

    2017-01-01

    Full Text Available This article addresses different duct static pressure control strategies which could be implemented in variable air volume air-conditioning systems (VAV. Two pressure reset control strategies are compared to the commonly used control solution based on the “Constant static pressure” method. First pressure reset control strategy, known as PID Control, uses signals from VAV boxes controllers to reset duct static pressure in a way that one of the VAV dampers is maintained almost entirely open. Second strategy decreases static pressure setpoint until an adjustable number of pressure requests occur. As a response to the certain amount of requests, static pressure setpoint is increased. This strategy is called Trim & Respond. Both static pressure reset control strategies described in this paper are considered to have more significant potential for energy savings than the “Constant static pressure” method. In order to validate this potential, several simulations for different control strategies were carried out and the obtained results are compared and analysed. The theoretical limit of the energy savings - set of the optimal control actions, was estimated with Nelder-Mead algorithm and also presented in this article. General description of the static pressure control strategies "Constant static pressure", PID Control and Trim & Respond is given.

  1. Neural Modeling of Fuzzy Controllers for Maximum Power Point Tracking in Photovoltaic Energy Systems

    Science.gov (United States)

    Lopez-Guede, Jose Manuel; Ramos-Hernanz, Josean; Altın, Necmi; Ozdemir, Saban; Kurt, Erol; Azkune, Gorka

    2018-06-01

    One field in which electronic materials have an important role is energy generation, especially within the scope of photovoltaic energy. This paper deals with one of the most relevant enabling technologies within that scope, i.e, the algorithms for maximum power point tracking implemented in the direct current to direct current converters and its modeling through artificial neural networks (ANNs). More specifically, as a proof of concept, we have addressed the problem of modeling a fuzzy logic controller that has shown its performance in previous works, and more specifically the dimensionless duty cycle signal that controls a quadratic boost converter. We achieved a very accurate model since the obtained medium squared error is 3.47 × 10-6, the maximum error is 16.32 × 10-3 and the regression coefficient R is 0.99992, all for the test dataset. This neural implementation has obvious advantages such as a higher fault tolerance and a simpler implementation, dispensing with all the complex elements needed to run a fuzzy controller (fuzzifier, defuzzifier, inference engine and knowledge base) because, ultimately, ANNs are sums and products.

  2. The Atomic Energy Control Board

    International Nuclear Information System (INIS)

    Doern, G.B.

    1976-01-01

    This study describes and assesses the regulatory and administrative processes and procedures of the Atomic Energy Control Board, the AECB. The Atomic Energy Control Act authorized the AECB to control atomic energy materials and equipment in the national interest and to participate in measures for the international control of atomic energy. The AECB is authorized to make regulations to control atomic energy materials and equipment and to make grants in support of atomic energy research. (author)

  3. Energy Storage System

    Science.gov (United States)

    1996-01-01

    SatCon Technology Corporation developed the drive train for use in the Chrysler Corporation's Patriot Mark II, which includes the Flywheel Energy Storage (FES) system. In Chrysler's experimental hybrid- electric car, the hybrid drive train uses an advanced turboalternator that generates electricity by burning a fuel; a powerful, compact electric motor; and a FES that eliminates the need for conventional batteries. The FES system incorporates technology SatCon developed in more than 30 projects with seven NASA centers, mostly for FES systems for spacecraft attitude control and momentum recovery. SatCon will continue to develop the technology with Westinghouse Electric Corporation.

  4. Design, Operation, Control, and Economics of a Photovoltaic/Fuel Cell/Battery Hybrid Renewable Energy System for Automotive Applications

    Directory of Open Access Journals (Sweden)

    Zachary S. Whiteman

    2015-06-01

    Full Text Available Meeting rapidly growing global energy demand—without producing greenhouse gases or further diminishing the availability of non-renewable resources—requires the development of affordable low-emission renewable energy systems. Here, we develop a hybrid renewable energy system (HRES for automotive applications—specifically, a roof-installed photovoltaic (PV array combined with a PEM fuel cell/NiCd battery bus currently operating shuttle routes on the University of Delaware campus. The system’s overall operating objectives—meeting the total power demand of the bus and maintaining the desired state of charge (SOC of the NiCd battery—are achieved with appropriately designed controllers: a logic-based “algebraic controller” and a standard PI controller. The design, implementation, and performance of the hybrid system are demonstrated via simulation of real shuttle runs under various operating conditions. The results show that both control strategies perform equally well in enabling the HRES to meet its objectives under typical operating conditions, and under sudden cloud cover conditions; however, at consistently high bus speeds, battery SOC maintenance is better, and the system consumes less hydrogen, with PI control. An economic analysis of the PV investment necessary to realize the HRES design objectives indicates a return on investment of approximately 30% (a slight, but nonetheless positive, ~$550 profit over the bus lifetime in Newark, DE, establishing the economic viability of the proposed addition of a PV array to the existing University of Delaware fuel cell/battery bus.

  5. Control of a Multi-Functional Inverter for Grid Integration of PV and Battery Energy Storage System

    DEFF Research Database (Denmark)

    Mousazadeh, Seyyed Yousef; Firoozabadi, Mehdi Savaghebi; Beirami, A.

    2015-01-01

    This paper presents a multi-functional control of a DC/AC inverter for Power Quality compensation of nonlinear and unequal local loads and grid integration of hybrid photovoltaic (PV) and battery energy storage systems. Multi-layer neural network estimator and a DC/DC converter are used for maximum...... is used for delivering desire power to the grid. For compensation aim, instantaneous active and reactive power theory (p-q) is used. Via the algorithm, the DC/AC inverter not only can be controlled to inject the power of battery and PV, but also it is used as shunt active filter for compensating unequal...... power point tracking (MPPT) of PV array. The power system is 3-phase 4-wires and the DC/AC inverter is chosen 4-leg three phase inverter which has good performance in presence of zero sequence components. Battery energy storage is connected to PV system in common DC bus and a power management strategy...

  6. WAMS Based Intelligent Operation and Control of Modern Power System with large Scale Renewable Energy Penetration

    DEFF Research Database (Denmark)

    Rather, Zakir Hussain

    security limits. Under such scenario, progressive displacement of conventional generation by wind generation is expected to eventually lead a complex power system with least presence of central power plants. Consequently the support from conventional power plants is expected to reach its all-time low...... system voltage control responsibility from conventional power plants to wind turbines. With increased wind penetration and displaced conventional central power plants, dynamic voltage security has been identified as one of the challenging issue for large scale wind integration. To address the dynamic...... security issue, a WAMS based systematic voltage control scheme for large scale wind integrated power system has been proposed. Along with the optimal reactive power compensation, the proposed scheme considers voltage support from wind farms (equipped with voltage support functionality) and refurbished...

  7. Croatian Energy System Defossilization

    International Nuclear Information System (INIS)

    Potocnik, V.

    2013-01-01

    Defossilization of an energy system, as primary cause of the actual climate change, means exchange of predominantly imported fossil fuels with climate more convenient energy carriers, facilitating thus the way out of crisis.Overview of the world and Croatian energy system situation is presented as well as the overview of climate change. The most important Croatian energy system defossilization measures-energy efficiency increase, renewable energy inclusion and others - are described.(author)

  8. Implementation of a Large Scale Control System for a High-Energy Physics Detector: The CMS Silicon Strip Tracker

    CERN Document Server

    Masetti, Lorenzo; Fischer, Peter

    2011-01-01

    Control systems for modern High-Energy Physics (HEP) detectors are large distributed software systems managing a significant data volume and implementing complex operational procedures. The control software for the LHC experiments at CERN is built on top of a commercial software used in industrial automation. However, HEP specific requirements call for extended functionalities. This thesis focuses on the design and implementation of the control system for the CMS Silicon Strip Tracker but presents some general strategies that have been applied in other contexts. Specific design solutions are developed to ensure acceptable response times and to provide the operator with an effective summary of the status of the devices. Detector safety is guaranteed by proper configuration of independent hardware systems. A software protection mechanism is used to avoid the widespread intervention of the hardware safety and to inhibit dangerous commands. A wizard approach allows non expert operators to recover error situations...

  9. Energy systems security

    CERN Document Server

    Voeller, John G

    2014-01-01

    Energy Systems Security features articles from the Wiley Handbook of Science and Technology for Homeland Security covering topics related to electricity transmission grids and their protection, risk assessment of energy systems, analysis of interdependent energy networks. Methods to manage electricity transmission disturbances so as to avoid blackouts are discussed, and self-healing energy system and a nano-enabled power source are presented.

  10. Coherently-enabled environmental control of optics and energy transfer pathways of hybrid quantum dot-metallic nanoparticle systems.

    Science.gov (United States)

    Hatef, Ali; Sadeghi, Seyed M; Fortin-Deschênes, Simon; Boulais, Etienne; Meunier, Michel

    2013-03-11

    It is well-known that optical properties of semiconductor quantum dots can be controlled using optical cavities or near fields of localized surface plasmon resonances (LSPRs) of metallic nanoparticles. In this paper we study the optics, energy transfer pathways, and exciton states of quantum dots when they are influenced by the near fields associated with plasmonic meta-resonances. Such resonances are formed via coherent coupling of excitons and LSPRs when the quantum dots are close to metallic nanorods and driven by a laser beam. Our results suggest an unprecedented sensitivity to the refractive index of the environment, causing significant spectral changes in the Förster resonance energy transfer from the quantum dots to the nanorods and in exciton transition energies. We demonstrate that when a quantum dot-metallic nanorod system is close to its plasmonic meta-resonance, we can adjust the refractive index to: (i) control the frequency range where the energy transfer from the quantum dot to the metallic nanorod is inhibited, (ii) manipulate the exciton transition energy shift of the quantum dot, and (iii) disengage the quantum dot from the metallic nanoparticle and laser field. Our results show that near meta-resonances the spectral forms of energy transfer and exciton energy shifts are strongly correlated to each other.

  11. Energy, economic and environmental performance simulation of a hybrid renewable microgeneration system with neural network predictive control

    Directory of Open Access Journals (Sweden)

    Evgueniy Entchev

    2018-03-01

    Full Text Available The use of artificial neural networks (ANNs in various applications has grown significantly over the years. This paper compares an ANN based approach with a conventional on-off control applied to the operation of a ground source heat pump/photovoltaic thermal system serving a single house located in Ottawa (Canada for heating and cooling purposes. The hybrid renewable microgeneration system was investigated using the dynamic simulation software TRNSYS. A controller for predicting the future room temperature was developed in the MATLAB environment and six ANN control logics were analyzed.The comparison was performed in terms of ability to maintain the desired indoor comfort levels, primary energy consumption, operating costs and carbon dioxide equivalent emissions during a week of the heating period and a week of the cooling period. The results showed that the ANN approach is potentially able to alleviate the intensity of thermal discomfort associated with overheating/overcooling phenomena, but it could cause an increase in unmet comfort hours. The analysis also highlighted that the ANNs based strategies could reduce the primary energy consumption (up to around 36%, the operating costs (up to around 81% as well as the carbon dioxide equivalent emissions (up to around 36%. Keywords: Hybrid microgeneration system, Ground source heat pump, Photovoltaic thermal, Artificial neural network, Predictive control, Energy saving

  12. Novel control algorithm of braking energy regeneration system for an electric vehicle during safety–critical driving maneuvers

    International Nuclear Information System (INIS)

    Lv, Chen; Zhang, Junzhi; Li, Yutong; Yuan, Ye

    2015-01-01

    Highlights: • Models of an electric vehicle with regenerative braking system (RBS) are built. • Control algorithm of RBS under safety–critical driving maneuvers is proposed. • Simulations and HIL tests of the proposed strategy are conducted. • Performance improvement of vehicle’s mean deceleration is up to 13.89%. • Test results verify the feasibility and effectiveness of the proposed method. - Abstract: This paper mainly focuses on control algorithm of the braking energy regeneration system of an electric bus under safety–critical driving situations. With the aims of guaranteeing vehicle stability in various types of tyre–road adhesion conditions, based on the characteristics of electrified powertrain, a novel control algorithm of regenerative braking system is proposed for electric vehicles during anti-lock braking procedures. First, the models of vehicle dynamics and main components including braking energy regenerative system of the case-study electric bus are built in MATLAB/Simulink. Then, based on the phase-plane method, the optimal brake torque is calculated for ABS control of vehicle. Next, a novel allocation strategy, wherein the target optimal brake torque is divided into two parts that are handled separately by the regenerative and friction brakes, is developed. Simulations of the proposed control strategy are conducted based on system models built using MATLAB/Simulink. The simulation results demonstrate that the developed strategy enables improved control in terms of vehicle stability and braking performance under different emergency driving conditions. To further verify the synthesized control algorithm, hardware-in-the-loop tests are also performed. The experimental results validate the simulation data and verify the feasibility and effectiveness of the developed control algorithm.

  13. Controllable Photovoltaic Grid Power Injection with an Assistance of Energy Storage System

    DEFF Research Database (Denmark)

    Morvaj, Boran; Dragicevic, Tomislav; Krajcar, Slavko

    2013-01-01

    This paper focuses on modeling and simulation of controllable Photovoltaic Battery Power System (PV BPS) interconnected to the electrical utility. After elaboration of modeling principles for different components appearing in the system, simulations of two types of PV plants connected to one branch...... of distribution network have been carried out. First one is connected through a three-phase inverter with battery string connected to a DC-link and the second string is connected to the grid in single phase configuration. In this proposed configuration unpredictable variations of irradiation and temperature...

  14. Principles for construction of control and stabilization systems for pulse energy sources on the base of compression generators

    International Nuclear Information System (INIS)

    Abdukaev, I.Kh.; Kuchinskij, V.G.; Titov, V.I.

    1984-01-01

    Principles of construction of control and stabilization systems for a compression-generator (CG)-sources of power energy pulses- are considered. CG is an electromechanical energy converter, the principle of its operation is based on magnetic flux compression with periodic change of mutual inductance of two rotating windings. In each period, with the decrease of intrinsic inductance the generator forms in the load the pulse leading edge, and in the phase rise a pulse decay. To obtain the same pulse in the following period it is neccessary that the magnetic flux initial value should be restored in the generator winding. Problems of attaining pule shaper amplitude stability are considered. The method of pulse amplitude control in the load at the expense of the change in switch moment of capacitive storage to CG windings is suggested. The block-diagram of stabilization system is presented and its operation principle is described. The control system is assembled using K 155 and K 511 microcircuits and it was tested with CG at the pulse energy to 10 kJ. The tests have shown, that already to the third pulse the system provided quite shaped series of pulses

  15. Experimental enhancement of fuzzy fractional order PI+I controller of grid connected variable speed wind energy conversion system

    International Nuclear Information System (INIS)

    Beddar, Antar; Bouzekri, Hacene; Babes, Badreddine; Afghoul, Hamza

    2016-01-01

    Highlights: • Fuzzy fractional order PI+I for wind energy conversion system is developed. • Investigation of the control methods performances under wind and load variations. • PSO algorithm with frequency method are used for parameters tuning. • Experimental results are presented. - Abstract: In this paper, fuzzy fractional order PI+I (FFOPI+I) controller for grid connected Variable Speed Wind Energy Conversion System (VS-WECS) is proposed. The FFOPI+I controller is applied to control a Permanent Magnet Synchronous Generator (PMSG) connected to the grid and nonlinear load through a back-to-back AC-DC-AC PWM converter. The control strategy of the Machine Side Converter (MSC) aims, at first, to extract a maximum power under fluctuating wind speed. Then, the Grid Side Converter (GSC) is controlled to improve the power quality and ensure sinusoidal current in the grid side. The FFOPI+I controller implements a Fuzzy Logic Controller (FLC) in parallel with Fractional Order PI (FOPI) and conventional PI controllers by having a commune proportional gain. The FLC changes the integral gains at runtime. The initial parameters of the FFOPI+I controller were calculated using a frequency method to create a search space then the PSO algorithm is used to select the optimal parameters. To evaluate the performance of the proposed controller in steady and transient states, an experimental test bench has been built in laboratory using dSPACE1104 card. The experimental results demonstrate the effectiveness and feasibility of the FFOPI+I over FOPI and conventional PI controllers by realizing maximum power extraction and improving the grid-side power factor for a wide range of wind speed.

  16. Influence of platform screen doors on energy consumption of the environment control system of a mass rapid transit system: case study of the Taipei MRT system

    International Nuclear Information System (INIS)

    Hu, S.-C.; Lee, J.-H.

    2004-01-01

    This investigation studies how platform screen doors (PSD) affect the energy consumption of the environmental control system of a mass rapid transit (MRT) system in Taipei. The environmental parameter simulation was conducted using the subway environmental simulation (SES) program, while the associated air conditioning (A/C) cooling load was predicted with the carrier E20-II program. Results show that PSD can significantly decrease average and peak cooling load, thus reducing the capacity/size of cooling equipment and allowing the chiller cooling load to be abridged. However, electricity consumption by ventilation equipment increases notably when PSD are used, particularly the electricity consumption by the under platform exhaust (UPE) fan, and thus, ultimately, little difference exists in the overall energy consumption with and without UPE

  17. Influence of platform screen doors on energy consumption of the environment control system of a mass rapid transit system: case study of the Taipei MRT system

    Energy Technology Data Exchange (ETDEWEB)

    Hu, S.-C. E-mail: f10870@ntut.edu.tw; Lee, J.-H

    2004-03-01

    This investigation studies how platform screen doors (PSD) affect the energy consumption of the environmental control system of a mass rapid transit (MRT) system in Taipei. The environmental parameter simulation was conducted using the subway environmental simulation (SES) program, while the associated air conditioning (A/C) cooling load was predicted with the carrier E20-II program. Results show that PSD can significantly decrease average and peak cooling load, thus reducing the capacity/size of cooling equipment and allowing the chiller cooling load to be abridged. However, electricity consumption by ventilation equipment increases notably when PSD are used, particularly the electricity consumption by the under platform exhaust (UPE) fan, and thus, ultimately, little difference exists in the overall energy consumption with and without UPE.

  18. Optimized Fuzzy-Cuckoo Controller for Active Power Control of Battery Energy Storage System, Photovoltaic, Fuel Cell and Wind Turbine in an Isolated Micro-Grid

    OpenAIRE

    Mohsen Einan; Hossein Torkaman; Mahdi Pourgholi

    2017-01-01

    This paper presents a new control strategy for isolated micro-grids including wind turbines (WT), fuel cells (FC), photo-voltaic (PV) and battery energy storage systems (BESS). FC have been used in parallel with BESSs in order to increase their lifetime and efficiency. The changes in some parameters such as wind speed, sunlight, and consumption, lead to improper performance of droop. To overcome this challenge, a new intelligent method using a combination of fuzzy controller and cuckoo optimi...

  19. National Renewable Energy Laboratory (NREL) Topic 2 Final Report: End-to-End Communication and Control System to Support Clean Energy Technologies

    Energy Technology Data Exchange (ETDEWEB)

    Hudgins, Andrew P. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Carrillo, Ismael M. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Jin, Xin [National Renewable Energy Lab. (NREL), Golden, CO (United States); Simmins, John [Electric Power Research Inst. (EPRI), Palo Alto, CA (United States)

    2018-02-21

    This document is the final report of a two-year development, test, and demonstration project, 'Cohesive Application of Standards- Based Connected Devices to Enable Clean Energy Technologies.' The project was part of the National Renewable Energy Laboratory's (NREL's) Integrated Network Testbed for Energy Grid Research and Technology (INTEGRATE) initiative hosted at Energy Systems Integration Facility (ESIF). This project demonstrated techniques to control distribution grid events using the coordination of traditional distribution grid devices and high-penetration renewable resources and demand response. Using standard communication protocols and semantic standards, the project examined the use cases of high/low distribution voltage, requests for volt-ampere-reactive (VAR) power support, and transactive energy strategies using Volttron. Open source software, written by EPRI to control distributed energy resources (DER) and demand response (DR), was used by an advanced distribution management system (ADMS) to abstract the resources reporting to a collection of capabilities rather than needing to know specific resource types. This architecture allows for scaling both horizontally and vertically. Several new technologies were developed and tested. Messages from the ADMS based on the common information model (CIM) were developed to control the DER and DR management systems. The OpenADR standard was used to help manage grid events by turning loads off and on. Volttron technology was used to simulate a homeowner choosing the price at which to enter the demand response market. Finally, the ADMS used newly developed algorithms to coordinate these resources with a capacitor bank and voltage regulator to respond to grid events.

  20. Model Predictive Control of a Wave Energy Converter with Discrete Fluid Power Power Take-Off System

    DEFF Research Database (Denmark)

    Hansen, Anders Hedegaard; Asmussen, Magnus Færing; Bech, Michael Møller

    2018-01-01

    Wave power extraction algorithms for wave energy converters are normally designed without taking system losses into account leading to suboptimal power extraction. In the current work, a model predictive power extraction algorithm is designed for a discretized power take of system. It is shown how...... the quantized nature of a discrete fluid power system may be included in a new model predictive control algorithm leading to a significant increase in the harvested power. A detailed investigation of the influence of the prediction horizon and the time step is reported. Furthermore, it is shown how...

  1. Application of a LiFePO4 Battery Energy Storage System to Primary Frequency Control: Simulations and Experimental Results

    Directory of Open Access Journals (Sweden)

    Fabio Massimo Gatta

    2016-10-01

    Full Text Available This paper presents an experimental application of LiFePO4 battery energy storage systems (BESSs to primary frequency control, currently being performed by Terna, the Italian transmission system operator (TSO. BESS performance in the primary frequency control role was evaluated by means of a simplified electrical-thermal circuit model, taking into account also the BESS auxiliary consumptions, coupled with a cycle-life model, in order to assess the expected life of the BESS. Numerical simulations have been carried out considering the system response to real frequency measurements taken in Italy, spanning a whole year; a parametric study taking into account different values of governor droop and of BESS charge/discharge rates (C-rates was also performed. Simulations, fully validated by experimental results obtained thus far, evidenced a severe trade-off between expected lifetime and overall efficiency, which significantly restricts the choice of operating parameters for frequency control.

  2. Adaptive Neuro-Fuzzy Inference Systems as a Strategy for Predicting and Controling the Energy Produced from Renewable Sources

    Directory of Open Access Journals (Sweden)

    Otilia Elena Dragomir

    2015-11-01

    Full Text Available The challenge for our paper consists in controlling the performance of the future state of a microgrid with energy produced from renewable energy sources. The added value of this proposal consists in identifying the most used criteria, related to each modeling step, able to lead us to an optimal neural network forecasting tool. In order to underline the effects of users’ decision making on the forecasting performance, in the second part of the article, two Adaptive Neuro-Fuzzy Inference System (ANFIS models are tested and evaluated. Several scenarios are built by changing: the prediction time horizon (Scenario 1 and the shape of membership functions (Scenario 2.

  3. Implementation and Assessment of a Decentralized Load Frequency Control: Application to Power Systems with High Wind Energy Penetration

    Directory of Open Access Journals (Sweden)

    Irene Muñoz-Benavente

    2017-01-01

    Full Text Available This paper describes and assesses a decentralized solution based on a wireless sensor-actuator network to provide primary frequency control from demand response in power systems with high wind energy penetration and, subsequently, with relevant frequency excursions. The proposed system is able to modify the electrical power demand of a variety of thermostatically-controlled loads, maintaining minimum comfort levels and minimizing both infrastructure requirements and primary reserves from the supply side. This low-cost hardware solution avoids any additional wiring, extending the wireless sensor-actuator network technology towards small customers, which account for over a 30% share of the current power demand. Frequency excursions are collected by each individual load controller, considering not only the magnitude of the frequency deviation, but also their evolution over time. Based on these time-frequency excursion characteristics, controllers are capable of modifying the power consumption of thermostatically-controlled loads by switching them off and on, thus contributing to primary frequency control in power systems with higher generation unit oscillations as a consequence of relevant wind power integration. Field tests have been carried out in a laboratory environment to assess the load controller performance, as well as to evaluate the electrical and thermal response of individual loads under frequency deviations. These frequency deviations are estimated from power systems with a high penetration of wind energy, which are more sensitive to frequency oscillations and where demand response can significantly contribute to mitigate these frequency excursions. The results, also included in the paper, evaluate the suitability of the proposed load controllers and their suitability to decrease frequency excursions from the demand side in a decentralized manner.

  4. Exploring the Impact of Fuel Data Acquisition Technology on the USMC Expeditionary Energy Command and Control System

    Science.gov (United States)

    2016-09-01

    CA: Sage Publications, Inc. Tulusan, J., Soi, L., Paefgen, J., Brogle, M., & Staake, T. (2011). Eco -efficient feedback technologies : Which eco ...IMPACT OF FUEL DATA ACQUISITION TECHNOLOGY ON THE USMC EXPEDITIONARY ENERGY COMMAND AND CONTROL SYSTEM by Jeremy F. Thomas September 2016...DATE September 2016 3. REPORT TYPE AND DATES COVERED Master’s Thesis 4. TITLE AND SUBTITLE EXPLORING THE IMPACT OF FUEL DATA ACQUISITION TECHNOLOGY

  5. Stochastic control and real options valuation of thermal storage-enabled demand response from flexible district energy systems

    OpenAIRE

    Kitapbayev, Yerkin; Moriarty, John; Mancarella, Pierluigi

    2014-01-01

    In district energy systems powered by Combined Heat and Power (CHP) plants, thermal storage can significantly increase CHP flexibility to respond to real time market signals and therefore improve the business case of such demand response schemes in a Smart Grid environment. However, main challenges remain as to what is the optimal way to control inter-temporal storage operation in the presence of uncertain market prices, and then how to value the investment into storage as flexibility enabler...

  6. Coordinated Control for Flywheel Energy Storage Matrix Systems for Wind Farm Based on Charging/Discharging Ratio Consensus Algorithms

    DEFF Research Database (Denmark)

    Cao, Qian; Song, Y. D.; Guerrero, Josep M.

    2016-01-01

    This paper proposes a distributed algorithm for coordination of flywheel energy storage matrix system (FESMS) cooperated with wind farm. A simple and distributed ratio consensus algorithm is proposed to solve FESMS dispatch problem. The algorithm is based on average consensus for both undirected...... and unbalanced directed graphs. Average consensus is guaranteed in unbalanced digraphs by updating the weight matrix with both its row sums and column sums being 1. Simulation examples illustrate the effectiveness of the proposed control method....

  7. Kinetic energy storage system

    Energy Technology Data Exchange (ETDEWEB)

    Jaeggi, M.; Folini, P.

    1983-09-03

    A flywheel system for the purpose of energy storage in decentral solar- or wind energy plants is introduced. The system comprises a rotor made out of plastic fibre, a motor/generator serving as electro-mechanical energy converter and a frequency-voltage transformer serving as electric adapter. The storable energy quantity amounts to several kWh.

  8. Model Predictive Control techniques with application to photovoltaic, DC Microgrid, and a multi-sourced hybrid energy system

    Science.gov (United States)

    Shadmand, Mohammad Bagher

    Renewable energy sources continue to gain popularity. However, two major limitations exist that prevent widespread adoption: availability and variability of the electricity generated and the cost of the equipment. The focus of this dissertation is Model Predictive Control (MPC) for optimal sized photovoltaic (PV), DC Microgrid, and multi-sourced hybrid energy systems. The main considered applications are: maximum power point tracking (MPPT) by MPC, droop predictive control of DC microgrid, MPC of grid-interaction inverter, MPC of a capacitor-less VAR compensator based on matrix converter (MC). This dissertation firstly investigates a multi-objective optimization technique for a hybrid distribution system. The variability of a high-penetration PV scenario is also studied when incorporated into the microgrid concept. Emerging (PV) technologies have enabled the creation of contoured and conformal PV surfaces; the effect of using non-planar PV modules on variability is also analyzed. The proposed predictive control to achieve maximum power point for isolated and grid-tied PV systems speeds up the control loop since it predicts error before the switching signal is applied to the converter. The low conversion efficiency of PV cells means we want to ensure always operating at maximum possible power point to make the system economical. Thus the proposed MPPT technique can capture more energy compared to the conventional MPPT techniques from same amount of installed solar panel. Because of the MPPT requirement, the output voltage of the converter may vary. Therefore a droop control is needed to feed multiple arrays of photovoltaic systems to a DC bus in microgrid community. Development of a droop control technique by means of predictive control is another application of this dissertation. Reactive power, denoted as Volt Ampere Reactive (VAR), has several undesirable consequences on AC power system network such as reduction in power transfer capability and increase in

  9. Energy management systems in buildings

    Energy Technology Data Exchange (ETDEWEB)

    Lush, D. M.

    1979-07-01

    An investigation is made of the range of possibilities available from three types of systems (automatic control devices, building envelope, and the occupants) in buildings. The following subjects are discussed: general (buildings, design and personnel); new buildings (envelope, designers, energy and load calculations, plant design, general design parameters); existing buildings (conservation measures, general energy management, air conditioned buildings, industrial buildings); man and motivation (general, energy management and documentation, maintenance, motivation); automatic energy management systems (thermostatic controls, optimized plant start up, air conditioned and industrial buildings, building automatic systems). (MCW)

  10. Wind energy conversion system

    Science.gov (United States)

    Longrigg, Paul

    1987-01-01

    The wind energy conversion system includes a wind machine having a propeller connected to a generator of electric power, the propeller rotating the generator in response to force of an incident wind. The generator converts the power of the wind to electric power for use by an electric load. Circuitry for varying the duty factor of the generator output power is connected between the generator and the load to thereby alter a loading of the generator and the propeller by the electric load. Wind speed is sensed electro-optically to provide data of wind speed upwind of the propeller, to thereby permit tip speed ratio circuitry to operate the power control circuitry and thereby optimize the tip speed ratio by varying the loading of the propeller. Accordingly, the efficiency of the wind energy conversion system is maximized.

  11. Adaptive Control Design for Autonomous Operation of Multiple Energy Storage Systems in Power Smoothing Applications

    DEFF Research Database (Denmark)

    Meng, Lexuan; Dragicevic, Tomislav; Guerrero, Josep M.

    2018-01-01

    -pass-filter (HPF) structure. It generates the power reference according to the fluctuating power and provides a stabilization effect. The power and energy supplied by ESS are majorly configured by the cut-off frequency and gain of the HPF. Considering the operational limits on ESS state-of-charge (SoC), this paper...... proposes an adaptive cut-off frequency design method to realize communication-less and autonomous operation of a system with multiple distributed ESS. The experimental results demonstrate that the SoCs of all ESS units are kept within safe margins, while the SoC level and power of the paralleled units...... converge to the final state, providing a natural plug-and-play function....

  12. Augmenting effectiveness of control loops of a PMSG (permanent magnet synchronous generator) based wind energy conversion system by a virtually adaptive PI (proportional integral) controller

    International Nuclear Information System (INIS)

    Alizadeh, Mojtaba; Kojori, Shokrollah Shokri

    2015-01-01

    Offering substantial features, PMSG (permanent magnet synchronous generator) based WECS (wind energy conversion system) is definitely one of the most reliable and efficient ways of extracting electrical power from the wind. Like other WECSs, PMSG-based WECS (PMSG WECS) encompasses two main control loops, each equipped with PI (proportional integral) controller, to control speed and currents of the system. This work develops a virtually adaptive PI controller to enhance the performance of both main control loops of a PMSG WECS. A WNN (wavelet neural network) is proposed to be added to each closed control loop in series with PI controller. Due to having a cascade connection, the transfer function of the WNN, which is a pure gain in each time step, is multiplied by PI gains. Therefore, the value of transfer function of the WNN, and consequently, both parameters of PI controller can be changed in each time step by online training of the WNN, resulting in a virtually adaptive PI controller. The performance of the proposed controller in improving efficacy of both current and speed control loops is evaluated by simulation studies and is also compared to that of PI controller, WNNC (wavelet neural network controller), and QNNC (quantum neural network controller). - Highlights: • To propose a virtually adaptive PI controller to be used in a PMSG WECS. • Both parameters of PI controller can be changed in each time step. • The proposed controller can be used as both current or speed controller. • The plant data is not required for offline training of proposed current controller.

  13. Distributed Control of Battery Energy Storage Systems for Voltage Regulation in Distribution Networks with High PV Penetration

    DEFF Research Database (Denmark)

    Zeraati, Mehdi; Golshan, Mohamad Esmaeil Hamedani; Guerrero, Josep M.

    2018-01-01

    of their installed capacity whereas the second one modifies the BESs performance in terms of their state of charge (SoC) to prevent the excessive saturation or depletion of batteries. The proposed controller enables the effective use of storage capacity in different conditions. Finally, the simulation results based...... issues of distribution networks. In this paper, the battery energy storage (BES) systems are used in order to solve the voltage rise during the peak PV generation as well as the voltage drop while meeting the peak load. A coordinated control strategy is proposed to regulate the charge/discharge of BESs...

  14. Design and Control of a Multi-Functional Energy Recovery Power Accumulator Battery Pack Testing System for Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Bo Long

    2014-03-01

    Full Text Available In this paper, aiming at the energy loss and harmonic problems in the conventional power accumulator battery pack testing system (PABPTS, an improved multi-functional energy recovery PABPTS (ERPABPTS for electric vehicles (EVs was proposed. The improved system has the functions of harmonic detection, suppression, reactive compensation and energy recovery. The ERPABPTS, which contains a bi-directional buck-boost direct current (DC-DC converter and a bi-directional alternating current (AC-DC converter with an inductor-capacitor-inductor (LCL type filter interfacing to the AC-grid, is proposed. System configuration and operation principle of the combined system are discussed first, then, the reactive compensation and harmonic suppression controller under balanced grid-voltage condition are presented. Design of a fourth order band-pass Butterworth filter for current harmonic detection is put forward, and the reactive compensator design procedure considering the non-linear load is also illustrated. The proposed scheme is implemented in a 175-kW prototype in the laboratory. Simulation and experimental results show that the combined configuration can effectively realize energy recovery for high accuracy current test requirement, meanwhile, can effectively achieve reactive compensation and current harmonic suppression.

  15. Automatic generation control of multi-area power systems with diverse energy sources using Teaching Learning Based Optimization algorithm

    Directory of Open Access Journals (Sweden)

    Rabindra Kumar Sahu

    2016-03-01

    Full Text Available This paper presents the design and analysis of Proportional-Integral-Double Derivative (PIDD controller for Automatic Generation Control (AGC of multi-area power systems with diverse energy sources using Teaching Learning Based Optimization (TLBO algorithm. At first, a two-area reheat thermal power system with appropriate Generation Rate Constraint (GRC is considered. The design problem is formulated as an optimization problem and TLBO is employed to optimize the parameters of the PIDD controller. The superiority of the proposed TLBO based PIDD controller has been demonstrated by comparing the results with recently published optimization technique such as hybrid Firefly Algorithm and Pattern Search (hFA-PS, Firefly Algorithm (FA, Bacteria Foraging Optimization Algorithm (BFOA, Genetic Algorithm (GA and conventional Ziegler Nichols (ZN for the same interconnected power system. Also, the proposed approach has been extended to two-area power system with diverse sources of generation like thermal, hydro, wind and diesel units. The system model includes boiler dynamics, GRC and Governor Dead Band (GDB non-linearity. It is observed from simulation results that the performance of the proposed approach provides better dynamic responses by comparing the results with recently published in the literature. Further, the study is extended to a three unequal-area thermal power system with different controllers in each area and the results are compared with published FA optimized PID controller for the same system under study. Finally, sensitivity analysis is performed by varying the system parameters and operating load conditions in the range of ±25% from their nominal values to test the robustness.

  16. Operational limits of a three level neutral point clamped converter used for controlling a hybrid energy storage system

    International Nuclear Information System (INIS)

    Etxeberria, A.; Vechiu, I.; Camblong, H.; Kreckelbergh, S.; Bacha, S.

    2014-01-01

    Highlights: • The control of a hybrid storage system using a Three Level NPC converter is analysed. • A sinusoidal PWM with an offset injection is used to control the storage system. • The operation of the selected converter is analysed in its entire operation range. • The operational limits of the Three Level NPC converter are defined. - Abstract: This work analyses the use of a Three-Level Neutral Point Clamped (3LNPC) converter to control the power flow of a Hybrid Energy Storage System (HESS) and at the same time interconnect it with the common AC bus of a microgrid. Nowadays there is not any storage technology capable of offering a high energy storage capacity, a high power capacity and a fast response at the same time. Therefore, the necessity of hybridising more than one storage technology is a widely accepted idea in order to satisfy the mentioned requirements. This work shows how the operational limits of the 3LNPC converter can be calculated and integrated in a control structure to facilitate an optimal use of the HESS according to the rules fixed by the user

  17. Research and application of an intelligent control system in central air-conditioning based on energy consumption simulation

    Science.gov (United States)

    Cao, Ling; Che, Wenbin

    2018-05-01

    For the central air-conditioning energy-saving, it is common practice to use a wide range of PTD controllers in engineering to optimize energy savings. However, the shortcomings of the PTD controller have also been magnified on this issue, such as: calculation accuracy is not enough, the calculation time is too long. Particle swarm optimization has the advantage of fast convergence. This paper is based on Particle Swarm Optimization apply in PTD controller tuning parameters in order to achieve the purpose of saving energy while ensuring comfort. The algorithm proposed in this paper can adjust the weight according to the change of population fitness, reduce the weights of particles with lower fitness and enhance the weights of particles with higher fitness in the population, and fully release the population vitality. The method in this paper is validated by the TRNSYS model based on the central air-conditioning system. The experimental results show that the room temperature fluctuation is small, the overshoot is small, the adjustment speed is fast, and the energy-saving fluctuates at 10%.

  18. Proceedings of the Technology Roadmap Workshop on Communication and Control Systems for Distributed Energy Implementation and Testing

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2002-05-01

    More than 50 experts from energy and information technology industries, Federal and State government agencies, universities, and National Laboratories participated in the “Communication and Control Systems for Distributed Energy Implementation and Testing Workshop” in Reston, Virginia, on May 14-15, 2002. This was a unique workshop in that, for the first time, representatives from the information technology sector and those from energy-related industries, Federal and State government agencies, universities, and National Laboratories, gathered to discuss these issues and develop a set of action-oriented implementation strategies. A planning committee of industry, consultant, and government representatives laid the groundwork for the workshop by identifying key participants and developing an appropriate agenda. This document reflects the ideas and priorities discussed by workshop participants.

  19. Micro-controller based fiber optic data telemetry system for the ion source of low energy accelerator facility at BARC

    International Nuclear Information System (INIS)

    Padmakumar, Sapna; Ware, Shailaja V.; Subrahmanyam, N.B.V.; Bhatt, J.P.; Singh, S.K.; Gupta, S.K.; Singh, P.; Choudhury, R.K.

    2009-01-01

    The Low Energy Accelerator Facility (LEAF) is a 50 keV, high intensity, negative ion accelerator facility that has been set up indigenously at Nuclear Physics Division, BARC. This facility is capable of delivering a wide range of negative ion beams of both light and heavy ions across the periodic table using a SNICS II (Source of Negative Ion by Caesium Sputtering) source. A micro-controller based control and monitoring system has been developed exclusively for the ion source parameters of LEAF. The data control and monitoring system mainly targets acquiring the data from the field in the terms of parameters such as voltages and currents. There are processes which need to be monitored continuously in order to keep certain parameters under check. The microcontroller based fiber optic data telemetry system allows us to perform the aforesaid task. The voltages can be controlled and monitored by providing the inputs and receiving the feedback through a user friendly graphic user interface. With this system one can control the status as well as analog value of the high voltage power supplies like extractor, cathode, filament, focus line heater and oven. This system consists of Fiber optic transceiver, which is connected on serial port (RS 232C) of microcontroller as well as RS232 port of PC. The whole control system is reliable even in noisy environments including RF and worse EMI conditions. This compact modular design is implemented using low cost devices and allows easy and fast maintainability. In the paper, the details of the system are presented. (author)

  20. Quantifying demand flexibility of power-to-heat and thermal energy storage in the control of building heating systems

    NARCIS (Netherlands)

    Finck, C.J.; Li, R.; Kramer, R.P.; Zeiler, W.

    2018-01-01

    In the future due to continued integration of renewable energy sources, demand-side flexibility would be required for managing power grids. Building energy systems will serve as one possible source of energy flexibility. The degree of flexibility provided by building energy systems is highly

  1. Energy conservation by technical means: the control systems matter.; Energiesparen durch technische Hilfsmittel: auf die Regelkreise kommt es an.

    Energy Technology Data Exchange (ETDEWEB)

    Benecke, J. [Verein Deutscher Ingenieure (VDI), Muenchen (Germany)

    2000-07-01

    The new German regulation on energy conservation in buildings (draft) offers certain flexibility for choosing the quality of the building envelope (thermal resistance and air tightness) and of the HV equipment (AC not considered) in order to balance and minimize the yearly heating-energy demand. Up to now, there was little consideration given to control systems which are able to assist the inhabitants in using heating and ventilation efficiently. The performance of such systems is being discussed. (orig.) [German] In Deutschland betraegt der Anteil der Raumheizenergie am Endenergieverbrauch rund 35%; ihr Anteil am Endenergieverbrauch der Haushalte und Kleinverbraucher betraegt rund 76%. Die Vorgaben der bisherigen Waermeschutzverordnungen und der geplanten Energieeinsparverordnung veranschaulichen das Energieeinsparpotential, das durch effizientere Energienutzung im Gebaeudebereich erschlossen werden kann. (orig.)

  2. A New Method for a Piezoelectric Energy Harvesting System Using a Backtracking Search Algorithm-Based PI Voltage Controller

    Directory of Open Access Journals (Sweden)

    Mahidur R. Sarker

    2016-09-01

    Full Text Available This paper presents a new method for a vibration-based piezoelectric energy harvesting system using a backtracking search algorithm (BSA-based proportional-integral (PI voltage controller. This technique eliminates the exhaustive conventional trial-and-error procedure for obtaining optimized parameter values of proportional gain (Kp, and integral gain (Ki for PI voltage controllers. The generated estimate values of Kp and Ki are executed in the PI voltage controller that is developed through the BSA optimization technique. In this study, mean absolute error (MAE is used as an objective function to minimize output error for a piezoelectric energy harvesting system (PEHS. The model for the PEHS is designed and analyzed using the BSA optimization technique. The BSA-based PI voltage controller of the PEHS produces a significant improvement in minimizing the output error of the converter and a robust, regulated pulse-width modulation (PWM signal to convert a MOSFET switch, with the best response in terms of rise time and settling time under various load conditions.

  3. [Nutrient sensing by the gastro-intestinal nervous system and control of energy homeostasis].

    Science.gov (United States)

    Gilles, Mithieux

    2015-01-01

    The gastrointestinal nerves are crucial in the sensing of nutrients and hormones and its translation in terms of control of food intake. Major macronutrients like glucose and proteins are sensed by the extrinsic nerves located around the portal vein walls, which signal to the brain and account for the satiety phenomenon they promote. Glucose is sensed in the portal vein by neurons expressing the glucose receptor SGLT3, which activates the main regions of the brain involved in the control of food intake. Proteins indirectly act on food intake by inducing intestinal gluconeogenesis and its sensing by the portal glucose sensor. The mechanism involves a prior antagonism by peptides of the μ-opioid receptors present in the portal vein nervous system and a reflex arc with the brain inducing intestinal gluconeogenesis. In a comparable manner, short chain fatty acids produced from soluble fibers act via intestinal gluconeogenesis to exert anti-obesity and anti-diabetic effects. In the case of propionate, the mechanism involves a prior activation of the free fatty acid receptor FFAR3 present in the portal nerves and a reflex arc initiating intestinal gluconeogenesis. © Société de Biologie, 2016.

  4. Real-Time Wavelet-Based Coordinated Control of Hybrid Energy Storage Systems for Denoising and Flattening Wind Power Output

    Directory of Open Access Journals (Sweden)

    Tran Thai Trung

    2014-10-01

    Full Text Available Since the penetration level of wind energy is continuously increasing, the negative impact caused by the fluctuation of wind power output needs to be carefully managed. This paper proposes a novel real-time coordinated control algorithm based on a wavelet transform to mitigate both short-term and long-term fluctuations by using a hybrid energy storage system (HESS. The short-term fluctuation is eliminated by using an electric double-layer capacitor (EDLC, while the wind-HESS system output is kept constant during each 10-min period by a Ni-MH battery (NB. State-of-charge (SOC control strategies for both EDLC and NB are proposed to maintain the SOC level of storage within safe operating limits. A ramp rate limitation (RRL requirement is also considered in the proposed algorithm. The effectiveness of the proposed algorithm has been tested by using real time simulation. The simulation model of the wind-HESS system is developed in the real-time digital simulator (RTDS/RSCAD environment. The proposed algorithm is also implemented as a user defined model of the RSCAD. The simulation results demonstrate that the HESS with the proposed control algorithm can indeed assist in dealing with the variation of wind power generation. Moreover, the proposed method shows better performance in smoothing out the fluctuation and managing the SOC of battery and EDLC than the simple moving average (SMA based method.

  5. Solar energy conversion systems

    CERN Document Server

    Brownson, Jeffrey R S

    2013-01-01

    Solar energy conversion requires a different mind-set from traditional energy engineering in order to assess distribution, scales of use, systems design, predictive economic models for fluctuating solar resources, and planning to address transient cycles and social adoption. Solar Energy Conversion Systems examines solar energy conversion as an integrative design process, applying systems thinking methods to a solid knowledge base for creators of solar energy systems. This approach permits different levels of access for the emerging broad audience of scientists, engineers, architects, planners

  6. Renewable Energy Systems

    DEFF Research Database (Denmark)

    Lund, Henrik; Mathiesen, Brian Vad; Connolly, David

    2014-01-01

    on the electricity sector, smart energy systems include the entire energy system in its approach to identifying suitable energy infrastructure designs and operation strategies. The typical smart grid sole focus on the electricity sector often leads to the conclusion that transmission lines, flexible electricity......This paper presents the learning of a series of studies that analyse the problems and perspectives of converting the present energy system into a 100 % renewable energy system using a smart energy systems approach. As opposed to, for instance, the smart grid concept, which takes a sole focus...... are to be found when the electricity sector is combined with the heating and cooling sectors and/or the transportation sector. Moreover, the combination of electricity and gas infrastructures may play an important role in the design of future renewable energy systems. The paper illustrates why electricity smart...

  7. An Innovative Control Strategy to Improve the Fault Ride-Through Capability of DFIGs Based on Wind Energy Conversion Systems

    Directory of Open Access Journals (Sweden)

    Vandai Le

    2016-01-01

    Full Text Available An innovative control strategy is proposed for enhancing the low voltage ride-through (LVRT capability of a doubly fed induction generator based on wind energy conversion systems (DFIG-WECS. Within the proposed control method, the current control loops of the rotor side converter (RSC are developed based on passivity theory. The control scheme for the grid side converter (GSC is designed based on a two-term approach to keep the DC-link voltage close to a given value. The first term based on the maximal voltage of GSC is introduced in the GSC control loops as a reference reactive current. The second one reflecting the instantaneous unbalanced power flow between the RSC and GSC is also introduced in the GSC control loops as a disturbance considering the instantaneous power of the grid filter to compensate the instantaneous rotor power. The effectiveness of the proposed control strategy is verified via time domain simulation of a 2.0 MW-575 V DFIG-WECS using PSCAD/EMTP. Simulation results show that the control of the DFIG with the proposed approach can improve the LVRT capability better than with the conventional one.

  8. Attempts to identify a control system for chemical reactivity in the living state using virtual energy.

    Science.gov (United States)

    Reid, B L; Bourke, C

    2001-07-01

    This thesis explores the activation of chemicals in metabolic systems from the viewpoint that this activation is under the control of elements of the space-sea in which the chemicals are immersed. Themselves inert, the chemicals are theorised to exploit a force or action issuing from space (fluctuation) and characterized by the homogeneity (termed symmetry) of this medium. The fluctuation is heterogenized upon collision with matter from the intervention of well recognized fields of gravity and electromagnetism at the instant of its issue to form the near field of radiation. Fractions of original space waves and of their intrinsic spin are produced resulting in the activation of the orbitals (valency) in the chemical itself. The thesis continues: the disturbed fluctuation must return to space, obliging in turn, a prior return to the homogeneous state requiring special restorative wave rearrangements known as resonance. The success of the restorative resonance is signalled by a singularity of the fluctuation now propelled to infinity (space), and the contingent chemical reactions thereby terminated. Compromise to this return can occur from many causes and, in its presence, activation of the orbitals continues. They now effectively constitute autonomous reactions alienated from the system as a whole. The thesis is supported from evidence from diverse fields such as space theory, history of quantum field theory in attempts to derive its meaning, dielectrics and the near field of electromagnetic radiation, electron-space interactions at the Fermi surface during phase transitions and evolution of equilibrium conditions in resonance phenomena. The utility of the hypothesis rests on recognition of the resonance condition at various points in the system sufficiently macroscopic as to be available clinically as an abrupt interface between physiology and pathology. Copyright 2001 Harcourt Publishers Ltd.

  9. FY 1999 report on energy conservation potential survey of measurement and control systems and energy-saving equipment

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-03-01

    Studies are conducted with a view to connecting a survey in Egypt to CDM (clean development mechanism) adopted at COP3 (Third Session of the Conference of the Parties to the United Nations Framework Convention on Climate Change). The survey covers the textile industry which is one of Egypt's main industries, and investigation is conducted for extending technical recommendation to 11 textile mills (including dyeing plants) about how to reduce greenhouse gas (CO2) emissions through energy conservation efforts. Required investment, investment recovery period, and reduction in CO2 emissions are calculated. About CO2 reduction, it is found that there will be a CO2 reduction of 44,702 tons/year at a rate of 22.4%, investment of 838.56-million yen, CO2 reduction of 53.3 tons/million yen, and investment of 18,750-yen/t-CO2. As for energy conservation, there will be a reduction at a rate of 14,449 toe/year in energy consumption, investment of 838.56-million yen, energy saved at a rate of 17.2 toe/million yen, and investment of 5,800 yen/toe. There will be an annual reduction in utility cost of 125.79-million yen at a cost reduction rate of 10.3%. The investment recovery period is calculated to be 5.8 years. The Egyptian textile has high potentials for CO2 reduction, and will present an excellent opportunity for a CDM project. (NEDO)

  10. Management information systems for controlling in energy supply companies; Management-Informationssysteme fuer das Controlling im EVU

    Energy Technology Data Exchange (ETDEWEB)

    Crombach, U. [CFI Controlling- und Fuehrungsinformationssysteme GmbH, Bodenheim (Germany); Ruf, J. [CFI Controlling- und Fuehrungsinformationssysteme GmbH, Bodenheim (Germany)

    1997-01-27

    Todays management information systems (MIS) allow flexible use of all data existing in the company for management and controlling. Instead of using fixed (coded) reports the user can easily decide about the presented data, either consolidated or in detail. Using well known Excel as front end for presentation and analysis provides easy access for all users. The authors describe how a data model for the MIS can be designed and stored in the `data warehouse` from the various sources in the company. A few typical charts are presented. (orig.) [Deutsch] Moderne Managementinformationssysteme (MIS) ermoeglichen die flexibel Nutzung aller im Unternehmen anfallenden Informationen fuer Fuehrung und Controlling. Anders als bei festgefuegten (programmierten) Auswertungen bestimmt der Nutzer frei ueber die dargestellten Informationen. Diese koennen einfach und schnell aus allen vorhandenen Datenquellen des Unternehmens zusammengefuehrt werden. Durch Verwendung der weit verbreiteten Tabellenkalkulationsprogramme, z.B. MS-Excel, als Bedieneroberflaeche, ist die Bedienung einfach erlernbar. Die Verfasser zeigen an einem Beispiel, wie ein solches MIS als Datenmodell konzipiert, einfach konfiguriert und schliesslich als Controllinginstrument flexible herangezogen werden kann. (orig.)

  11. Remote control systems evolution in the new open energy market; Evoluzione del telecontrollo nel nuovo mercato dell'energia

    Energy Technology Data Exchange (ETDEWEB)

    Castiglioni, L. [Soluzioni hardware/software per l' automazione e il controllo degli impianti industriali, Taizzano sul Naviglio, Milan (Italy)

    2001-12-01

    Considering new energy market in Italy, the new role of remote control applications is discussed. In the open market the whole electric process is managed by several different actors; common protocol scheme and additional sharing data policies are necessaries facing the increased communications requirements due to deregulation. Remote control systems evolution then will lead from process oriented to data management oriented systems; related methodologies and solutions are described. [Italian] Il telecontrollo, nell'ambito del nuovo mercato dell'energia, diviene di importanza fondamentale per la necessita' di condivisione dei dati verso il livello di pianificazione e di analisi prestazionale. Viene individuata una linea evolutiva per i sistemi di telecontrollo, dove da un'attenzione rivolta al processo si passa a sistemi orientati all'apertura verso l'esterno e al data management. Vengono descritte alcune metodologie orientate allo scambio dati tra centri e verso sistemi esterni.

  12. Neural Network Based Maximum Power Point Tracking Control with Quadratic Boost Converter for PMSG—Wind Energy Conversion System

    Directory of Open Access Journals (Sweden)

    Ramji Tiwari

    2018-02-01

    Full Text Available This paper proposes an artificial neural network (ANN based maximum power point tracking (MPPT control strategy for wind energy conversion system (WECS implemented with a DC/DC converter. The proposed topology utilizes a radial basis function network (RBFN based neural network control strategy to extract the maximum available power from the wind velocity. The results are compared with a classical Perturb and Observe (P&O method and Back propagation network (BPN method. In order to achieve a high voltage rating, the system is implemented with a quadratic boost converter and the performance of the converter is validated with a boost and single ended primary inductance converter (SEPIC. The performance of the MPPT technique along with a DC/DC converter is demonstrated using MATLAB/Simulink.

  13. Optimized Fuzzy-Cuckoo Controller for Active Power Control of Battery Energy Storage System, Photovoltaic, Fuel Cell and Wind Turbine in an Isolated Micro-Grid

    Directory of Open Access Journals (Sweden)

    Mohsen Einan

    2017-08-01

    Full Text Available This paper presents a new control strategy for isolated micro-grids including wind turbines (WT, fuel cells (FC, photo-voltaic (PV and battery energy storage systems (BESS. FC have been used in parallel with BESSs in order to increase their lifetime and efficiency. The changes in some parameters such as wind speed, sunlight, and consumption, lead to improper performance of droop. To overcome this challenge, a new intelligent method using a combination of fuzzy controller and cuckoo optimization algorithm (COA techniques for active power controllers in isolated networks is proposed. In this paper, COA is compared with genetic algorithm (GA and particles swarm optimization algorithm (PSO. In order to show efficiency of the proposed controller, this optimal controller has been compared with droop, optimized droop, and conventional fuzzy methods, the dynamic analysis of the island is implemented to assess the behavior of isolated generations accurately and simulation results are reported.

  14. A Neural Network Controller for Variable-Speed Variable-Pitch Wind Energy Conversion Systems Using Generalized Minimum Entropy Criterion

    Directory of Open Access Journals (Sweden)

    Mifeng Ren

    2014-01-01

    Full Text Available This paper considers the neural network controller design problem for variable pitch wind energy conversion systems (WECS with non-Gaussian wind speed disturbances in the stochastic distribution control framework. The approach here is used to directly model the unknown control law based on a fixed neural network (the number of layers and nodes in a neural network is fixed without the need to construct a separate model for the WECS. In order to characterize the randomness of the WECS, a generalized minimum entropy criterion is established to train connection weights of the neural network. For the train purpose, both kernel density estimation method and sliding window technique are adopted to estimate the PDF of tracking error and entropies. Due to the unknown process dynamics, the gradient of the objective function in a gradient-descent-type algorithm is estimated using an incremental perturbation method. The proposed approach is illustrated on a simulated WECS with non-Gaussian wind speed.

  15. Flexible energy systems

    DEFF Research Database (Denmark)

    Lund, Henrik

    2003-01-01

    The paper discusses and analyses diffent national strategies and points out key changes in the energy system in order to achieve a system which can benefit from a high percentage of wind and CHP without having surplus production problems, introduced here as a flexible energy system....

  16. Government control or low carbon lifestyle? – Analysis and application of a novel selective-constrained energy-saving and emission-reduction dynamic evolution system

    International Nuclear Information System (INIS)

    Fang, Guochang; Tian, Lixin; Fu, Min; Sun, Mei

    2014-01-01

    This paper explores a novel selective-constrained energy-saving and emission-reduction (ESER) dynamic evolution system, analyzing the impact of cost of conserved energy (CCE), government control, low carbon lifestyle and investment in new technology of ESER on energy intensity and economic growth. Based on artificial neural network, the quantitative coefficients of the actual system are identified. Taking the real situation in China for instance, an empirical study is undertaken by adjusting the parameters of the actual system. The dynamic evolution behavior of energy intensity and economic growth in reality are observed, with the results in perfect agreement with actual situation. The research shows that the introduction of CCE into ESER system will have certain restrictive effect on energy intensity in the earlier period. However, with the further development of the actual system, carbon emissions could be better controlled and energy intensity would decline. In the long run, the impacts of CCE on economic growth are positive. Government control and low carbon lifestyle play a decisive role in controlling ESER system and declining energy intensity. But the influence of government control on economic growth should be considered at the same time and the controlling effect of low carbon lifestyle on energy intensity should be strengthened gradually, while the investment in new technology of ESER can be neglected. Two different cases of ESER are proposed after a comprehensive analysis. The relations between variables and constraint conditions in the ESER system are harmonized remarkably. A better solution to carry out ESER is put forward at last, with numerical simulations being carried out to demonstrate the results. - Highlights: • Use of nonlinear dynamical method to model the selective-constrained ESER system. • Monotonic evolution curves of energy intensity and economic growth are obtained. • Detailed analysis of the game between government control and low

  17. Real time simulation of nonlinear generalized predictive control for wind energy conversion system with nonlinear observer.

    Science.gov (United States)

    Ouari, Kamel; Rekioua, Toufik; Ouhrouche, Mohand

    2014-01-01

    In order to make a wind power generation truly cost-effective and reliable, an advanced control techniques must be used. In this paper, we develop a new control strategy, using nonlinear generalized predictive control (NGPC) approach, for DFIG-based wind turbine. The proposed control law is based on two points: NGPC-based torque-current control loop generating the rotor reference voltage and NGPC-based speed control loop that provides the torque reference. In order to enhance the robustness of the controller, a disturbance observer is designed to estimate the aerodynamic torque which is considered as an unknown perturbation. Finally, a real-time simulation is carried out to illustrate the performance of the proposed controller. Copyright © 2013 ISA. Published by Elsevier Ltd. All rights reserved.

  18. Control strategy of wind turbine based on permanent magnet synchronous generator and energy storage for stand-alone systems

    DEFF Research Database (Denmark)

    Deng, Fujin; Liu, Dong; Chen, Zhe

    2017-01-01

    This paper investigates a variable speed wind turbine based on permanent magnet synchronous generator and a full-scale power converter in a stand-alone system. An energy storage system(ESS) including battery and fuel cell-electrolyzer combination is connected to the DC link of the full-scale power...... converter through the power electronics interface. Wind is the primary power source of the system, the battery and FC-electrolyzer combination is used as a backup and a long-term storage system to provide or absorb power in the stand-alone system, respectively. In this paper, a control strategy is proposed...... for the operation of this variable speed wind turbine in a stand-alone system, where the generator-side converter and the ESS operate together to meet the demand of the loads. This control strategy is competent for supporting the variation of the loads or wind speed and limiting the DC-link voltage of the full...

  19. Automated control of a solar microgrid-powered air compressor for use in a small-scale compressed air energy storage system

    OpenAIRE

    Williams, Joshua N.

    2017-01-01

    Approved for public release; distribution is unlimited As part of the Office of Naval Research's study of advanced energy technologies, this research examined the development and implementation of a control system for the compression phase of a small-scale compressed air energy storage system, using a solar-powered microgrid to store energy as compressed air for later use. The compression system is composed of numerous commercial-off-the-shelf components wherever possible. All electronic c...

  20. Enhanced Control for a Direct-driven Permanent Synchronous Generator Wind-power Generation System with Flywheel Energy Storage Unit Under Unbalanced Grid Fault

    DEFF Research Database (Denmark)

    Yao, Jun; Zhou, Te; Hu, Weihao

    2015-01-01

    This article presents an enhanced control strategy for a direct-driven permanent synchronous generator based wind-power generation system with a flywheel energy storage unit. The behaviors of the direct-driven permanent magnet synchronous generator system with a flywheel energy storage unit under......, the DC-link voltage oscillations can be effectively suppressed during the unbalanced grid fault by controlling the flywheel energy storage unit. Furthermore, a proportional–integral-resonant controller is designed for the flywheel motor to eliminate the oscillations in the DC-link voltage. Finally......, the proposed coordinated control strategy for the direct-driven permanent magnet synchronous generator system with a flywheel energy storage unit has been validated by the simulation results of a 1-MW direct-driven permanent magnet synchronous generator wind power generation system with a flywheel energy...

  1. LCA of Energy Systems

    DEFF Research Database (Denmark)

    Laurent, Alexis; Espinosa Martinez, Nieves; Hauschild, Michael Zwicky

    2018-01-01

    Energy systems are essential in the support of modern societies’ activities, and can span a wide spectrum of electricity and heat generation systems and cooling systems. Along with their central role and large diversity, these systems have been demonstrated to cause serious impacts on human health...... , ecosystems and natural resources. Over the past two decades, energy systems have thus been the focus of more than 1000 LCA studies, with the aim to identify and reduce these impacts. This chapter addresses LCA applications to energy systems for generation of electricity and heat . The chapter gives insight...

  2. Secure Automated Microgrid Energy System

    Science.gov (United States)

    2016-12-01

    O&M Operations and Maintenance PSO Power System Optimization PV Photovoltaic RAID Redundant Array of Independent Disks RBAC Role...elements of the initial study and operational power system model (feeder size , protective devices, generation sources, controllable loads, transformers...EW-201340) Secure Automated Microgrid Energy System December 2016 This document has been cleared for public release; Distribution Statement A

  3. Development and testing of a digital RF control system and development of a modular data acquisition system for the energy stabilisation of the S-DALINAC

    International Nuclear Information System (INIS)

    Araz, Asim

    2009-01-01

    approximately unchanged. To achieve the required amplitude stability of 8 .10 -5 further improvements to the control algorithm are needed. Within the framework of this thesis, an universal and modular data acquisition system was put into operation, being the basis of an active energy stabilization system for the electron beam by means of time of flight analysis. The required analysing system was designed and installed. First tests showed that relative energy shifts of 7.6.10 -5 can be measured reliably. Meanwhile, the modular data acquisition system is used for diagnostic purposes and for the processing of additional signals. These include the acquisition of beam currents, the monitoring of temperatures and the control of the high-voltage platform. (orig.)

  4. System control and communication

    International Nuclear Information System (INIS)

    Bindner, H.; Oestergaard, J.

    2005-01-01

    Rapid and ongoing development in the energy sector has consequences for system control at all levels. In relation to system control and communication the control system is challenged in five important ways: 1) Expectations for security of supply, robustness and vulnerability are becoming more stringent, and the control system plays a big part in meeting these expectations. 2) Services are becoming increasingly based on markets that involve the transmission system operators (TSOs), generators and distribution companies. Timely, accurate and secure communication is essential to the smooth running of the markets. 3) Adding large amounts of renewable energy (RE) to the mix is a challenge for control systems because of the intermittent availability of many RE sources. 4) Increasing the number of active components in the system, such as small CHP plants, micro-CHP and intelligent loads, means that the system control will be much more complex. 5) In the future it is likely that power, heat, gas, transport and communication systems will be tighter coupled and interact much more. (au)

  5. On Early Conflict Identification by Requirements Modeling of Energy System Control Structures

    DEFF Research Database (Denmark)

    Heussen, Kai; Gehrke, Oliver; Niemann, Hans Henrik

    2015-01-01

    issues early. For requirements formulation of control structures, cyber and physical aspects need to be jointly represented to express interdependencies, check for consistency and discover potentially conflicting requirements. Early identification of potential conflicts may prevent larger problems...... at later design stages. However, languages employed for requirements modeling today do not offer the expressiveness necessary to represent control purposes in relation to domain level interactions and therefore miss several types of interdependencies. This paper introduces the idea of control structure...... modeling for early requirements checking using a suitable modeling language, and illustrates how this approach enables the identification of several classes of controller conflict....

  6. Energy Systems Integration Newsletter - December 2016 | Energy Systems

    Science.gov (United States)

    system makes renewable energy integration easier. ESIF Research Shows That Connected Residential Devices and business intelligence. Baggu also noted the opportunity to harness next-generation graphical -through, ramp rate control, soft-start reconnection, and voltage-watt control. NREL then conducted power

  7. An Efficient Demand Side Management System with a New Optimized Home Energy Management Controller in Smart Grid

    Directory of Open Access Journals (Sweden)

    Hafiz Majid Hussain

    2018-01-01

    Full Text Available The traditional power grid is inadequate to overcome modern day challenges. As the modern era demands the traditional power grid to be more reliable, resilient, and cost-effective, the concept of smart grid evolves and various methods have been developed to overcome these demands which make the smart grid superior over the traditional power grid. One of the essential components of the smart grid, home energy management system (HEMS enhances the energy efficiency of electricity infrastructure in a residential area. In this aspect, we propose an efficient home energy management controller (EHEMC based on genetic harmony search algorithm (GHSA to reduce electricity expense, peak to average ratio (PAR, and maximize user comfort. We consider EHEMC for a single home and multiple homes with real-time electricity pricing (RTEP and critical peak pricing (CPP tariffs. In particular, for multiple homes, we classify modes of operation for the appliances according to their energy consumption with varying operation time slots. The constrained optimization problem is solved using heuristic algorithms: wind-driven optimization (WDO, harmony search algorithm (HSA, genetic algorithm (GA, and proposed algorithm GHSA. The proposed algorithm GHSA shows higher search efficiency and dynamic capability to attain optimal solutions as compared to existing algorithms. Simulation results also show that the proposed algorithm GHSA outperforms the existing algorithms in terms of reduction in electricity cost, PAR, and maximize user comfort.

  8. Renewable Energy Tracking Systems

    Science.gov (United States)

    Renewable energy generation ownership can be accounted through tracking systems. Tracking systems are highly automated, contain specific information about each MWh, and are accessible over the internet to market participants.

  9. Reducing energy consumption and leakage by active pressure control in a water supply system

    NARCIS (Netherlands)

    Bakker, M.; Rajewicz, T.; Kien, H.; Vreeburg, J.H.G.; Rietveld, L.C.

    2013-01-01

    WTP Gruszczyn supplies drinking water to a part of the city of Pozna?, in the Midwest of Poland. For the optimal automatic pressure control of the clear water pumping station, nine pressure measuring points were installed in the distribution network, and an active pressure control model was

  10. Impact of energy efficiency goals on systems of building regulations and control

    NARCIS (Netherlands)

    Visscher, H.J.; Meijer, F.M.

    2014-01-01

    Considerations of climate change, but also other political and economic reasons urge for the reduction of use of fossil fuels and the minimization of environmental impact by the built environment. The energy saving potential of the building stock is large and considered to be the most cost efficient

  11. Min-Max control of fuel-cell-car-based smart energy systems

    NARCIS (Netherlands)

    Alavi, F.; van de Wouw, N.; de Schutter, B.

    2016-01-01

    Recently, the idea of using fuel cell vehicles as the future way of producing electricity has emerged. A fuel cell car has all the necessary devices on board to convert the chemical energy of hydrogen into electricity. This paper considers a scenario where a parking lot for fuel cell cars acts as a

  12. Min-max control of fuel-cell-car-based smart energy systems

    NARCIS (Netherlands)

    Alavi, F.; van de Wouw, N.; De Schutter, B.H.K.; Rantzer, Anders; Bagterp Jørgensen, John; Stoustrup, Jakob

    2016-01-01

    Recently, the idea of using fuel cell vehicles as the future way of producing electricity has emerged. A fuel cell car has all the necessary devices on board to convert the chemical energy of hydrogen into electricity. This paper considers a scenario where a parking lot for fuel cell cars acts as a

  13. Modeling and Control System Design for an Integrated Solar Generation and Energy Storage System with a Ride-Through Capability: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Wang, X.; Yue, M.; Muljadi, E.

    2012-09-01

    This paper presents a generic approach for PV panel modeling. Data for this modeling can be easily obtained from manufacturer datasheet, which provides a convenient way for the researchers and engineers to investigate the PV integration issues. A two-stage power conversion system (PCS) is adopted in this paper for the PV generation system and a Battery Energy Storage System (BESS) can be connected to the dc-link through a bi-directional dc/dc converter. In this way, the BESS can provide some ancillary services which may be required in the high penetration PV generation scenario. In this paper, the fault ride-through (FRT) capability is specifically focused. The integrated BESS and PV generation system together with the associated control systems is modeled in PSCAD and Matlab platforms and the effectiveness of the controller is validated by the simulation results.

  14. New secondary energy systems

    International Nuclear Information System (INIS)

    Schulten, R.

    1977-01-01

    As an introduction, the FRG's energy industry situation is described, secondary energy systems to be taken into consideration are classified, and appropriate market requirements are analyzed. Dealt with is district heating, i.e. the direct transport of heat by means of circulating media, and long-distance energy, i.e. the long-distance energy transport by means of chemical conversion in closed- or open-cycle systems. In closed-cycle systems heat is transported in the form of chemical latent energy. In contrast to this, chemical energy is transported in open-cycle systems in the form of fuel gases produced by coal gasification or by thermochemical water splitting. (GG) [de

  15. PGC-1alpha Deficiency Causes Multi-System Energy Metabolic Derangements: Muscle Dysfunction, Abnormal Weight Control and Hepatic Steatosis

    Directory of Open Access Journals (Sweden)

    Leone Teresa C

    2005-01-01

    Full Text Available The gene encoding the transcriptional coactivator peroxisome proliferator-activated receptor-gamma coactivator-1alpha (PGC-1alpha was targeted in mice. PGC-1alpha null (PGC-1alpha-/- mice were viable. However, extensive phenotyping revealed multi-system abnormalities indicative of an abnormal energy metabolic phenotype. The postnatal growth of heart and slow-twitch skeletal muscle, organs with high mitochondrial energy demands, is blunted in PGC-1alpha-/- mice. With age, the PGC-1alpha-/- mice develop abnormally increased body fat, a phenotype that is more severe in females. Mitochondrial number and respiratory capacity is diminished in slow-twitch skeletal muscle of PGC-1alpha-/- mice, leading to reduced muscle performance and exercise capacity. PGC-1alpha-/- mice exhibit a modest diminution in cardiac function related largely to abnormal control of heart rate. The PGC-1alpha-/- mice were unable to maintain core body temperature following exposure to cold, consistent with an altered thermogenic response. Following short-term starvation, PGC-1alpha-/- mice develop hepatic steatosis due to a combination of reduced mitochondrial respiratory capacity and an increased expression of lipogenic genes. Surprisingly, PGC-1alpha-/- mice were less susceptible to diet-induced insulin resistance than wild-type controls. Lastly, vacuolar lesions were detected in the central nervous system of PGC-1alpha-/- mice. These results demonstrate that PGC-1alpha is necessary for appropriate adaptation to the metabolic and physiologic stressors of postnatal life.

  16. PGC-1alpha deficiency causes multi-system energy metabolic derangements: muscle dysfunction, abnormal weight control and hepatic steatosis.

    Directory of Open Access Journals (Sweden)

    Teresa C Leone

    2005-04-01

    Full Text Available The gene encoding the transcriptional coactivator peroxisome proliferator-activated receptor-gamma coactivator-1alpha (PGC-1alpha was targeted in mice. PGC-1alpha null (PGC-1alpha(-/- mice were viable. However, extensive phenotyping revealed multi-system abnormalities indicative of an abnormal energy metabolic phenotype. The postnatal growth of heart and slow-twitch skeletal muscle, organs with high mitochondrial energy demands, is blunted in PGC-1alpha(-/- mice. With age, the PGC-1alpha(-/- mice develop abnormally increased body fat, a phenotype that is more severe in females. Mitochondrial number and respiratory capacity is diminished in slow-twitch skeletal muscle of PGC-1alpha(-/- mice, leading to reduced muscle performance and exercise capacity. PGC-1alpha(-/- mice exhibit a modest diminution in cardiac function related largely to abnormal control of heart rate. The PGC-1alpha(-/- mice were unable to maintain core body temperature following exposure to cold, consistent with an altered thermogenic response. Following short-term starvation, PGC-1alpha(-/- mice develop hepatic steatosis due to a combination of reduced mitochondrial respiratory capacity and an increased expression of lipogenic genes. Surprisingly, PGC-1alpha(-/- mice were less susceptible to diet-induced insulin resistance than wild-type controls. Lastly, vacuolar lesions were detected in the central nervous system of PGC-1alpha(-/- mice. These results demonstrate that PGC-1alpha is necessary for appropriate adaptation to the metabolic and physiologic stressors of postnatal life.

  17. 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

    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......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...... stability. Finally, corresponding hardware in the loop results based on dSPACE1006 platform have been reported in order to verify the validity of proposed approach....

  18. Advanced Motor Control Test Facility for NASA GRC Flywheel Energy Storage System Technology Development Unit

    Science.gov (United States)

    Kenny, Barbara H.; Kascak, Peter E.; Hofmann, Heath; Mackin, Michael; Santiago, Walter; Jansen, Ralph

    2001-01-01

    This paper describes the flywheel test facility developed at the NASA Glenn Research Center with particular emphasis on the motor drive components and control. A four-pole permanent magnet synchronous machine, suspended on magnetic bearings, is controlled with a field orientation algorithm. A discussion of the estimation of the rotor position and speed from a "once around signal" is given. The elimination of small dc currents by using a concurrent stationary frame current regulator is discussed and demonstrated. Initial experimental results are presented showing the successful operation and control of the unit at speeds up to 20,000 rpm.

  19. Optimal Real-Time Scheduling for Hybrid Energy Storage Systems and Wind Farms Based on Model Predictive Control

    Directory of Open Access Journals (Sweden)

    Meng Xiong

    2015-08-01

    Full Text Available Energy storage devices are expected to be more frequently implemented in wind farms in near future. In this paper, both pumped hydro and fly wheel storage systems are used to assist a wind farm to smooth the power fluctuations. Due to the significant difference in the response speeds of the two storages types, the wind farm coordination with two types of energy storage is a problem. This paper presents two methods for the coordination problem: a two-level hierarchical model predictive control (MPC method and a single-level MPC method. In the single-level MPC method, only one MPC controller coordinates the wind farm and the two storage systems to follow the grid scheduling. Alternatively, in the two-level MPC method, two MPC controllers are used to coordinate the wind farm and the two storage systems. The structure of two level MPC consists of outer level and inner level MPC. They run alternatively to perform real-time scheduling and then stop, thus obtaining long-term scheduling results and sending some results to the inner level as input. The single-level MPC method performs both long- and short-term scheduling tasks in each interval. The simulation results show that the methods proposed can improve the utilization of wind power and reduce wind power spillage. In addition, the single-level MPC and the two-level MPC are not interchangeable. The single-level MPC has the advantage of following the grid schedule while the two-level MPC can reduce the optimization time by 60%.

  20. Thermal energy storage apparatus, controllers and thermal energy storage control methods

    Science.gov (United States)

    Hammerstrom, Donald J.

    2016-05-03

    Thermal energy storage apparatus, controllers and thermal energy storage control methods are described. According to one aspect, a thermal energy storage apparatus controller includes processing circuitry configured to access first information which is indicative of surpluses and deficiencies of electrical energy upon an electrical power system at a plurality of moments in time, access second information which is indicative of temperature of a thermal energy storage medium at a plurality of moments in time, and use the first and second information to control an amount of electrical energy which is utilized by a heating element to heat the thermal energy storage medium at a plurality of moments in time.

  1. Energy Systems Integration Facility News | Energy Systems Integration

    Science.gov (United States)

    Facility | NREL Energy Systems Integration Facility News Energy Systems Integration Facility Energy Dataset A massive amount of wind data was recently made accessible online, greatly expanding the Energy's National Renewable Energy Laboratory (NREL) has completed technology validation testing for Go

  2. Pricing and Inventory Control Strategy for a Periodic-Review Energy Buy-Back System

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jihong; CHEN Hongqiao; DING Xiaosong; LI Xian

    2016-01-01

    Along with the rapid development of economics and enhancement of industrialization,the power demand keeps rising and frequently creates mismatch between demand and supply in electricity.This provides miscellaneous energy buy-back programs with great opportunities.Such programs,when activated,offer certain amount of financial compensations to participants for reducing their energy consumption during peak time.They aim at encouraging participants to shift their electricity usage from peak to non-peak time,and thereby release the demand pressure during peak time.This paper considers a periodic-review joint pricing and inventory decision model under an energy buy-back program over finite planning horizons,in which the compensation levels,setup cost and additive random demand function are incorporated.The objective is to maximize a manufacturer's expected total profit.By using Veinott's conditions,it is shown that the manufacturer's optimal decision is a state dependent (s,S,P) policy under a peak market condition,or partly an (s,S,A,P) policy under the normal market condition.

  3. Higher energy efficiency and better water quality by using model predictive flow control at water supply systems

    NARCIS (Netherlands)

    Bakker, M.; Verberk, J.Q.J.C.; Palmen, L.J.; Sperber, V.; Bakker, G.

    2011-01-01

    Half of all water supply systems in the Netherlands are controlled by model predictive flow control; the other half are controlled by conventional level based control. The differences between conventional level based control and model predictive control were investigated in experiments at five full

  4. The Development of Smart Home System for Controlling and Monitoring Energy Consumption using WebSocket Protocol

    Science.gov (United States)

    Witthayawiroj, Niti; Nilaphruek, Pongpon

    2017-03-01

    Energy consumption especially electricity is considered one of the most serious problems in households these days. It is because the amount of electricity consumed is more than the amount that people actually need. This means that there is an overusing which resulted from the inconvenience of moving to the switch to turn off the light or any appliances and it is often that closing the light is forgettable, for instance; in addition, there are no tools for monitoring how much energy that is consumed in residents. From this, it can be easily seen that people are having a problem in energy usage monitor and control. There are two main objectives of this study including 1) creating the communication framework among server, clients and devices, and 2) developing the prototype system that try to solve the mentioned problems which gives the user an opportunity to know the amount of electricity they have used in their houses and also the ability to turn appliances on and off through the Internet on smart devices such as smart phones and tablets that support Android platform or any web browser. Raspberry Pi is used as a microcontroller and the data is transferred to the smart device by WebSocket protocol which is strongly recommended for real-time communication. The example features on the device’s screen are user management, controlling and monitoring of appliances. The result expresses that the system is very effective and not difficult to use from users’ satisfaction. However, current sensors may be used for a more accurate electricity measurement and Wi-Fi module for more appliances to calculate its power in the future.

  5. Coordinated control of smart microgrid during and after islanding operation to prevent under frequency load shedding using energy storage system

    International Nuclear Information System (INIS)

    Koohi-Kamali, Sam; Rahim, Nasrudin Abd

    2016-01-01

    Highlights: • A new power management system is proposed. • The novel idea of using energy storage systems to prevent under frequency load shedding is presented. • A method to estimate rate of change of frequency in islanding mode and to dispatch battery plant is introduced. • Two effective outer control loops are proposed for governor to synchronize the microgrid with main grid. • Solar photovoltaic and battery plants bring the voltage regulation ancillary service for microgrid. - Abstract: This work presents a smart microgrid consisting of diesel, photovoltaic (PV), and battery storage plants. One of the key features of smart grid is to provide a redundant high quality power for the consumers. In islanded microgrid, the under frequency and/or voltage collapse, caused by power deficiency, can lead to power outage. The current practice is to shed the load demand until the frequency and voltage are restored. However, the redundancy in supplying power has no meaning as long as the loads are shed. The main objective of this paper is to propose a power management system (PMS) that protects the microgrid against the load shedding. PMS is able to control the microgrid in both centralized and decentralized fashions. To prevent under frequency load shedding (UFLS), this work proposes using battery energy storage system (BESS) to compensate for the power mismatch in the islanded microgrid. A method is presented to estimate the rate of change of frequency and to calculate the power deficiency. The approximated value is exploited as the set-point to dispatch BESS. PV and battery plants are supposed to share the reactive power demand proportionally and thus regulate the voltage at the load bus. This work also suggests two outer control loops, namely, frequency restoration loop (FRL) and difference angle compensator (DAC). These loops ensure microgrid smooth transition from islanded mode to grid-connected mode. The microgrid is configured to investigate the effective

  6. What Is Energy Systems Integration? | Energy Systems Integration Facility |

    Science.gov (United States)

    NREL What Is Energy Systems Integration? What Is Energy Systems Integration? Energy systems integration (ESI) is an approach to solving big energy challenges that explores ways for energy systems to Research Community NREL is a founding member of the International Institute for Energy Systems Integration

  7. A multi-agent decentralized energy management system based on distributed intelligence for the design and control of autonomous polygeneration microgrids

    International Nuclear Information System (INIS)

    Karavas, Christos-Spyridon; Kyriakarakos, George; Arvanitis, Konstantinos G.; Papadakis, George

    2015-01-01

    Highlights: • A decentralized energy management system based on multi agent systems theory. • A decentralized energy management system is technically feasible. • A decentralized approach utilizes the devices better than a centralized one. • A decentralized energy management system is economically competitive. - Abstract: The autonomous polygeneration microgrid topology has been developed in order to cover holistically needs in a remote area such as electrical energy, space heating and cooling, potable water through desalination and hydrogen as fuel for transportation. The existence of an advanced energy management system is essential for the operation of an autonomous polygeneration microgrid. So far, energy management systems based on a centralized management and control have been developed for the autonomous polygeneration microgrid topology based on computational intelligence approaches. A decentralized management and control energy management system can have important benefits, when taking into consideration the autonomous character of these microgrids. This paper presents the design and investigation of a decentralized energy management system for the autonomous polygeneration microgrid topology. The decentralized energy management system gives the possibility to control each unit of the microgrid independently. The most important advantage of using a decentralized architecture is that the managed microgrid has much higher chances of partial operation in cases when malfunctions occur at different parts of it, instead of a complete system breakdown. The designed system was based on a multi-agent system and employed Fuzzy Cognitive Maps for its implementation. It was then compared through a case study with an existing centralized energy management system. The technical performance of the decentralized solution performance is on par with the existing centralized one, presenting improvements in financial and operational terms for the implementation and

  8. Energy Management and Control of Plug-In Hybrid Electric Vehicle Charging Stations in a Grid-Connected Hybrid Power System

    Directory of Open Access Journals (Sweden)

    Sidra Mumtaz

    2017-11-01

    Full Text Available The charging infrastructure plays a key role in the healthy and rapid development of the electric vehicle industry. This paper presents an energy management and control system of an electric vehicle charging station. The charging station (CS is integrated to a grid-connected hybrid power system having a wind turbine maximum power point tracking (MPPT controlled subsystem, photovoltaic (PV MPPT controlled subsystem and a controlled solid oxide fuel cell with electrolyzer subsystem which are characterized as renewable energy sources. In this article, an energy management system is designed for charging and discharging of five different plug-in hybrid electric vehicles (PHEVs simultaneously to fulfil the grid-to-vehicle (G2V, vehicle-to-grid (V2G, grid-to-battery storage system (G2BSS, battery storage system-to-grid (BSS2G, battery storage system-to-vehicle (BSS2V, vehicle-to-battery storage system (V2BSS and vehicle-to-vehicle (V2V charging and discharging requirements of the charging station. A simulation test-bed in Matlab/Simulink is developed to evaluate and control adaptively the AC-DC-AC converter of non-renewable energy source, DC-DC converters of the storage system, DC-AC grid side inverter and the converters of the CS using adaptive proportional-integral-derivate (AdapPID control paradigm. The effectiveness of the AdapPID control strategy is validated through simulation results by comparing with conventional PID control scheme.

  9. Energy control policy

    International Nuclear Information System (INIS)

    Moisan, F.; Bosseboeuf, D.

    1995-01-01

    The report 'energy efficiency policies' shows the evolution of energy efficiency for different countries since the first petroleum crisis. The countries concerned by this study are European countries, North America ones, Japan, Eastern Asia countries and some out of OECD such Brazil, Chile, Poland. The results are presented in a global way and then by industry sectors, transports and tertiary and residential sectors. 8 tabs

  10. Front Surface Tandem Filters using Sapphire (Al2O3) Substrates for Spectral Control in thermophotovoltaic Energy Conversion Systems

    International Nuclear Information System (INIS)

    T Rahmlow, Jr.; J Lazo-Wasem; E Gratrix; P Fourspring; D DePoy

    2005-01-01

    Front surface filters provide an effective means of improving thermophotovoltaic (TPV) system efficiency through spectral control of incident radiant energy. A front surface filter reflects the below band gap photons that can not be converted by the TPV cell back towards the high temperature radiator and allows convertible above band gap photons to pass through the filter into the TPV cell for conversion to electricity. The best spectral control efficiency to date has been demonstrated by front surface, tandem filters that combine an interference filter and an InPAs layer (plasma filter) in series. The InPAs material is a highly doped, epitaxially grown layer on an InP substrate. These tandem filter designs have been fabricated with energy and angle weighted spectral efficiencies of 76% for TPV cells with a 2.08(micro)m (0.6eV) band gap [1]. An alternative to the InPAs layer on an InP substrate is an Al 2 O 3 (sapphire) substrate. The use of Al 2 O 3 may increase transmission of above band gap photons, increase the mechanical strength of the tandem filter, and lower the cost of the tandem filter, all at the expense of lower spectral efficiency. This study presents design and fabrication results for front surface tandem filters that use an Al 2 O 3 substrate for 2.08(micro)m band gap TPV cells

  11. Energy production systems engineering

    CERN Document Server

    Blair, Thomas Howard

    2017-01-01

    Energy Production Systems Engineering presents IEEE, Electrical Apparatus Service Association (EASA), and International Electrotechnical Commission (IEC) standards of engineering systems and equipment in utility electric generation stations. Electrical engineers that practice in the energy industry must understand the specific characteristics of electrical and mechanical equipment commonly applied to energy production and conversion processes, including the mechanical and chemical processes involved, in order to design, operate and maintain electrical systems that support and enable these processes. To aid this understanding, Energy Production Systems Engineeringdescribes the equipment and systems found in various types of utility electric generation stations. This information is accompanied by examples and practice problems. It also addresses common issues of electrical safety that arise in electric generation stations.

  12. Energy efficiency system development

    Science.gov (United States)

    Leman, A. M.; Rahman, K. A.; Chong, Haw Jie; Salleh, Mohd Najib Mohd; Yusof, M. Z. M.

    2017-09-01

    By subjecting to the massive usage of electrical energy in Malaysia, energy efficiency is now one of the key areas of focus in climate change mitigation. This paper focuses on the development of an energy efficiency system of household electrical appliances for residential areas. Distribution of Questionnaires and pay a visit to few selected residential areas are conducted during the fulfilment of the project as well as some advice on how to save energy are shared with the participants. Based on the collected data, the system developed by the UTHM Energy Team is then evaluated from the aspect of the consumers' behaviour in using electrical appliances and the potential reduction targeted by the team. By the end of the project, 60% of the participants had successfully reduced the electrical power consumption set by the UTHM Energy Team. The reasons for whether the success and the failure is further analysed in this project.

  13. Energy Monitoring and Control Systems--Performance Verification and Endurance Test Procedures.

    Science.gov (United States)

    1982-12-01

    EM-; tK2 s) trave h.en loadted in qvstem sit ~rp sm:l , o,1 ti-’.~ -1 rouiitthe factoz’, lest. E.VEF.NT Comnmwid the system to display the status of...contractor correction of all outstanding deficiencies . 163 TEST NO: END-i Page I of 1 OBJECTIVE: To demonstrate EMCS normal mode operation 24 TITLE: Endurance

  14. Nano-scale control of energy transfer in the system 'donor-acceptor'

    International Nuclear Information System (INIS)

    Malyukin, Yu.V.; Yefimova, S.L.; Lebedenko, A.N.; Sorokin, A.V.; Borovoy, I.A.

    2005-01-01

    Fluorescence resonance energy transfer (FRET) in a cascade scheme between three amphiphilic dyes 3,3'-dioctadecyloxacarbocyanine perchlorate (DiOC 18 (3), donor), 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate (DiIC 18 (3), acceptor/donor) and 1,1'-dioctadecyl-3,3,3',3'-tetramethylindodicarbocyanine perchlorate (DiIC 18 (5), acceptor) has been investigated at low dye concentration (10 -5 mol/l) in water-micellar solutions due to a forced assembling of dyes in nanoscale volume. The experimental data have revealed that sodium dodecyl sulfate (SDS) micelles solubilize dye molecules such that their hydrophilic heads are in contact with water, while hydrophobic tails are embedded into the hydrocarbon core of the micelle. FRET efficiency has been found to depend on the concentration of dyes in micelles and the most effective when each SDS micelle contains 1 donor (DiOC 18 (3)), 2 acceptor/donor (DiIC 18 (3)) and 4 acceptor (DiIC 18 (5)) molecules

  15. Stochastic control and real options valuation of thermal storage-enabled demand response from flexible district energy systems

    International Nuclear Information System (INIS)

    Kitapbayev, Yerkin; Moriarty, John; Mancarella, Pierluigi

    2015-01-01

    Highlights: • We calculate the real option value of flexibility from CHP-thermal storage. • Stochastic optimal feedback control problem is solved under uncertain market prices. • Efficient real-time numerical solutions combine simulation, regression and recursion. • Clear, interpretable feedback control maps are produced for each hour of the day. • We give a realistic UK case study using projected market gas and electricity prices. - Abstract: In district energy systems powered by Combined Heat and Power (CHP) plants, thermal storage can significantly increase CHP flexibility to respond to real time market signals and therefore improve the business case of such demand response schemes in a Smart Grid environment. However, main challenges remain as to what is the optimal way to control inter-temporal storage operation in the presence of uncertain market prices, and then how to value the investment into storage as flexibility enabler. In this outlook, the aim of this paper is to propose a model for optimal and dynamic control and long term valuation of CHP-thermal storage in the presence of uncertain market prices. The proposed model is formulated as a stochastic control problem and numerically solved through Least Squares Monte Carlo regression analysis, with integrated investment and operational timescale analysis equivalent to real options valuation models encountered in finance. Outputs are represented by clear and interpretable feedback control strategy maps for each hour of the day, thus suitable for real time demand response under uncertainty. Numerical applications to a realistic UK case study with projected market gas and electricity prices exemplify the proposed approach and quantify the robustness of the selected storage solutions

  16. Controlling energy demand. What history?

    International Nuclear Information System (INIS)

    Beers, Marloes; Bonhomme, Noel; Bouvier, Yves; Pautard, Eric; Fevrier, Patrick; Lanthier, Pierre; Goyens, Valerie; Desama, Claude; Beltran, Alain

    2012-01-01

    this special dossier of the historical annals of electricity collection takes stock of the post 1970's history of energy demand control in industrialized countries: Abatement of energy dependence, the European Communities program of rational use of energy in the 1970's (Marloes Beers); The G7 and the energy cost: the limits of dialogue between industrialized countries - 1975-1985 (Noel Bonhomme); Saving more to consume more. The ambiguity of EDF's communication during the 'energy saving' era (Yves Bouvier); From rationing to energy saving certificates, 4 decades of electricity demand control in France and in the UK (eric Pautard); The French agency of environment and energy mastery (ADEME): between energy control and sustainable development (Patrick Fevrier); Hydro-Quebec and efficiency in household energy consumption, from 1990 to the present day (Pierre Lanthier); Control of energy consumption since the 1970's, the policy of rational use of energy in Walloon region - Belgium (Valerie Goyens); Electricity distribution in the new energy paradigm (Claude Desama); Conclusion (Alain Beltran)

  17. Smart Energy Systems and Energy Transition

    International Nuclear Information System (INIS)

    Duic, N.

    2016-01-01

    Transition to decarbonized energy systems is becoming more attractive with fall of investment costs of renewables and volatile prices and political insecurity of fossil fuels. Improving energy efficiency, especially of buildings and transport, is important, but due to long life of buildings, it will be a slow way of decarbonization. The renewable energy resources are bountiful, especially wind and solar, while integrating them into current energy systems is proving to be a challenge. Solar has reached grid parity making it cheapest electricity source for retail customers in most of the World, creating new prosumer markets. It has started to reach cost parity in sunny countries, and soon solar energy will be cheapest everywhere. The limit of cheap and easy integration for wind is around 20% of yearly electricity generation, while a combined wind and solar may reach 30%. Going any further asks for implementation of completely free energy markets (involving day ahead, intraday and various reserve and ancillary services markets), demand response, coupling of wholesale and retail energy prices, and it involves integration between electricity, heat, water and transport systems. The cheapest and simplest way of increasing further the penetration of renewables is integrating power and heating/cooling systems through the use of district heating and cooling (which may be centrally controlled and may have significant heat storage capacity), since power to heat technologies are excellent for demand response. District cooling is of particular importance to historic cities that want to remove split systems from their facades. In countries with low heat demand water supply system may be used to increase the penetration of renewables, by using water at higher potential energy as storage media, or in dry climates desalination and stored water may be used for those purposes, and reversible hydro may be used as balancing technology. Electrification of personal car transport allows

  18. Energy Usage Analysis System

    Data.gov (United States)

    General Services Administration — The EUAS application is a web based system which serves Energy Center of Expertise, under the Office of Facilitates Management and Service Programs. EUAS is used for...

  19. Load Control System Reliability

    Energy Technology Data Exchange (ETDEWEB)

    Trudnowski, Daniel [Montana Tech of the Univ. of Montana, Butte, MT (United States)

    2015-04-03

    This report summarizes the results of the Load Control System Reliability project (DOE Award DE-FC26-06NT42750). The original grant was awarded to Montana Tech April 2006. Follow-on DOE awards and expansions to the project scope occurred August 2007, January 2009, April 2011, and April 2013. In addition to the DOE monies, the project also consisted of matching funds from the states of Montana and Wyoming. Project participants included Montana Tech; the University of Wyoming; Montana State University; NorthWestern Energy, Inc., and MSE. Research focused on two areas: real-time power-system load control methodologies; and, power-system measurement-based stability-assessment operation and control tools. The majority of effort was focused on area 2. Results from the research includes: development of fundamental power-system dynamic concepts, control schemes, and signal-processing algorithms; many papers (including two prize papers) in leading journals and conferences and leadership of IEEE activities; one patent; participation in major actual-system testing in the western North American power system; prototype power-system operation and control software installed and tested at three major North American control centers; and, the incubation of a new commercial-grade operation and control software tool. Work under this grant certainly supported the DOE-OE goals in the area of “Real Time Grid Reliability Management.”

  20. Strategies and Decision Support Systems for Integrating Variable Energy Resources in Control Centers for Reliable Grid Operations

    Energy Technology Data Exchange (ETDEWEB)

    Jones, Lawrence E. [Alstom Grid Inc., Washington, DC (United States)

    2011-11-01

    This report provides findings from the field regarding the best ways in which to guide operational strategies, business processes and control room tools to support the integration of renewable energy into electrical grids.

  1. Strategies and Decision Support Systems for Integrating Variable Energy Resources in Control Centers for Reliable Grid Operations. Executive Summary

    Energy Technology Data Exchange (ETDEWEB)

    Jones, Lawrence E. [Alstom Grid, Inc., Washington, DC (United States)

    2011-11-01

    This is the executive summary for a report that provides findings from the field regarding the best ways in which to guide operational strategies, business processes and control room tools to support the integration of renewable energy into electrical grids.

  2. Flow energy conversion system

    International Nuclear Information System (INIS)

    Sargsyan, R.A.

    2011-01-01

    A cost-effective hydropower system called here Flow Energy Converter was developed, patented, manufactured and tested for water pumping, electricity generation and other purposes especially useful for the rural communities. The system consists of water-driven turbine with plane-surface blades, power transmission means and pump and/or generator. Working sample of the Flow Energy Converter was designed and manufactured at the Institute of Radio Physics and Electronics

  3. Management and monitoring of public buildings through ICT based systems: Control rules for energy saving with lighting and HVAC services

    OpenAIRE

    Aghemo, C.; Virgone, J.; Fracastoro, G.V.; Pellegrino, A.; Blaso, L.; Savoyat, J.; Johannes, Kevyn

    2013-01-01

    The presented work addresses the topic of energy savings in existing public buildings, when no significant retrofits on building envelope or plants can be done and savings can be achieved by designing intelligent ICT-based service to monitor and control environmental conditions, energy loads and plants operation. At the end of 2010 the European Commission, within the Seventh Framework Program, has founded a project entitled “Smart Energy Efficient Middleware for Public Spaces” (SEEMPubS). To ...

  4. Solar Energy Systems

    Science.gov (United States)

    1984-01-01

    Calibrated in kilowatt hours per square meter, the solar counter produced by Dodge Products, Inc. provides a numerical count of the solar energy that has accumulated on a surface. Solar energy sensing, measuring and recording devices in corporate solar cell technology developed by Lewis Research Center. Customers for their various devices include architects, engineers and others engaged in construction and operation of solar energy facilities; manufacturers of solar systems or solar related products, such as glare reducing windows; and solar energy planners in federal and state government agencies.

  5. Living Systems Energy Module

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-09-26

    The Living Systems Energy Module, renamed Voyage from the Sun, is a twenty-lesson curriculum designed to introduce students to the major ways in which energy is important in living systems. Voyage from the Sun tells the story of energy, describing its solar origins, how it is incorporated into living terrestrial systems through photosynthesis, how it flows from plants to herbivorous animals, and from herbivores to carnivores. A significant part of the unit is devoted to examining how humans use energy, and how human impact on natural habitats affects ecosystems. As students proceed through the unit, they read chapters of Voyage from the Sun, a comic book that describes the flow of energy in story form (Appendix A). During the course of the unit, an ``Energy Pyramid`` is erected in the classroom. This three-dimensional structure serves as a classroom exhibit, reminding students daily of the importance of energy and of the fragile nature of our living planet. Interactive activities teach students about adaptations that allow plants and animals to acquire, to use and to conserve energy. A complete list of curricular materials and copies of all activity sheets appear in Appendix B.

  6. Alternative Energy Systems

    Energy Technology Data Exchange (ETDEWEB)

    West, M.; Duckers, L.; Lockett, P.; Loughridge, B.; Peatfield, T.; White, P.

    1984-01-01

    The Coventry (Lanchester) Polytechnic Wave Energy Group has been involved in the United Kingdom wave energy research programme since its inception in 1975. Whilst the work of the group is mainly concerned with wave energy, and currently is directed towards the design of a wave energy device tailored to the needs of isolated/island communities, it has some involvement with other aspects of the alternatives. This conference, dealing with alternative energy systems and their electrical integration and utilisation was engendered by the general interest which the Polytechnic group members have in the alternatives and their use. The scope for electrical integration and utilisation is very broad. Energy for family groups may be provided in a relatively unsophisticated way which is acceptable to them. Small population centres, for example island communities relying upon diesel equipment, can reap the benefits of the alternatives through their ability to accept novel integration schemes and a flexible approach to the use of the energy available. Consumers already enjoying the benefits of a 'firm' electricity grid supply can use energy from a variety of alternative systems, via the grid, without having to modify their energy consumption habits. In addition to the domestic and industrial applications and coastal possibilities, specialist applications in isolated environments have also emerged. The Proceedings detail practical, technical and economic aspects of the alternatives and their electrical integration and utilisation.

  7. TECHNICAL AND ENERGY PARAMETERS IMPROVEMENT OF DIESEL LOCOMOTIVES THROUGH THE INTRODUCTION OF AUTOMATED CONTROL SYSTEMS OF A DIESEL

    Directory of Open Access Journals (Sweden)

    M. I. Kapitsa

    2015-04-01

    Full Text Available Purpose. Today the issue, connected with diesel traction remains relevant for the majority of industrial enterprises and Ukrainian railways and diesel engine continues to be the subject of extensive research and improvements. Despite the intensive process of electrification, which accompanies Railway Transport of Ukraine the last few years, diesel traction continues to play an important role both in the main and in the industrial railway traction rolling stock. Anyway, all kinds of maneuvering and chores are for locomotives, they are improved and upgraded relentlessly and hourly. This paper is focused on finding the opportunities to improve technical and energy parameters of diesels due to the development of modern control method of the fuel equipment in the diesel engine. Methodology. The proposed method increases the power of locomotives diesel engines in the range of crankshaft rotation (from idle running to maximum one. It was based on approach of mixture ignition timing up to the top «dead» center of piston position. Findings. The paper provides a brief historical background of research in the area of operating cycle in the internal combustion engine (ICE. The factors affecting the process of mixing and its quality were analyzed. The requirements for fuel feed system in to the cylinder and the «weak points» of the process were presented. A variant of the modification the fuel pump drive, which allows approaching to the regulation of fuel feed system from the other hand and to improve it was proposed. Represents a variant of embodiment of the complex system with specification of mechanical features and control circuits. The algorithm of the system operation was presented and its impact on the performance of diesel was made. Originality. The angle regulating system of fuel supply allows automating the process of fuel injection advance angle into the cylinder. Practical value. At implementation the angle regulating system of fuel supply

  8. Use cases for integrated electrical and thermal energy systems operation and control with a view on simulation tools

    DEFF Research Database (Denmark)

    Gehrke, Oliver; Richert, Thibaut Pierre

    2017-01-01

    There is a general lack of knowledge regarding energy systems coupling (also known as multi-energy systems (MES), multi-domain or integrated energy systems) and few well-defined use cases (UCs) that properly describe their operation. Energy systems coupling increases complexity due to additional...... and discuss why we consider these UCs to be the most representative of such systems. Based on these UCs we derive requirements for simulation tools and level of detail (e.g. technical and temporal resolution) to simulate MES in a holistic way. We relate these requirements to the existing tools for studying...... could have an impact into another. We show that no single tool exists to cover all UCs and why such a tool may not be desirable after all....

  9. Frequency-Division Power Sharing and Hierarchical Control Design for DC Shipboard Microgrids with Hybrid Energy Storage Systems

    DEFF Research Database (Denmark)

    Jin, Zheming; Meng, Lexuan; Quintero, Juan Carlos Vasquez

    2017-01-01

    Due to the increasing need to reduce the cost and emission of ships, shipboard applications are calling advanced technologies to go onboard. Recently, cleaner power sources (i.e. gas turbines, fuel cell, solar and wind power), energy storage, advanced control and power/energy management......, the operation point of prime movers can be maintained at their optimal area, meanwhile, different energy storages will provide characteristic based response. On the basis of the proposed power sharing method, voltage restoration and power management-level control methods are also introduced to form hierarchical...

  10. Introduction to Renewable Energy Systems

    DEFF Research Database (Denmark)

    Ma, Ke; Yang, Yongheng; Blaabjerg, Frede

    2014-01-01

    . It is concluded that as the quick development of renewable energy, wind power and PV power both show great potential to be largely integrated into the power grid. Power electronics is playing essential role in both of the systems to achieve more controllable, efficient, and reliable energy production......In this chapter, the state-of-the-arts developments of renewable energy are reviewed in respect to the installed power and market share, where wind power and photovoltaic power generation are the main focuses due to the fast growing speed and large share of installed capacity. Some basic principles...... of operation, mission profiles, as well as power electronics solutions and corresponding controls are discussed respectively in the case of wind power and photovoltaic power systems. Finally a few development trends for renewable energy conversions are also given from a power electronics point of view...

  11. Update of energy performance certificates in the residential sector and scenarios that consider the impact of automation, control and management systems: A case study of La Rioja

    International Nuclear Information System (INIS)

    López-González, Luis M.; López-Ochoa, Luis M.; Las-Heras-Casas, Jesús; García-Lozano, César

    2016-01-01

    Highlights: • A total of 9416 energy performance certificates in the residential sector were analyzed. • Approximately 40% of the energy performance certificates were incorrect. • The developed algorithms can be generalized for the remainder of Spain. • Introducing BACS and TBM systems can reduce building energy consumption by up to 26.36%. - Abstract: Energy performance certificates are considered to be tools for knowledge and energy planning in the residential sector. Although energy performance certificates describe primary energy consumption and the associated emissions of a home or building, they do not consider the influence of building automation control systems (BACS) or technical building management (TBM) systems on these parameters. The European Standard EN 15232 remedies this shortcoming and evaluates the savings in primary energy and the reduction of CO_2 emissions that can be achieved by these systems. This study investigates the energy performance certificates registered in the Autonomous Community of La Rioja and considers the policy changes in the Technical Building Code (Código Técnico de la Edificación) and, specifically, the Basic Document for Energy Saving (Documento Básico de Ahorro de Energía) (CTE-DB-HE). Due to this regulatory change, we corrected the certificates and outlined different scenarios based on the implementation of these systems in this study. These scenarios show the potential distribution of energy performance certificates and the improvements in the ratings obtained.

  12. Energy saving synergies in national energy systems

    DEFF Research Database (Denmark)

    Thellufsen, Jakob Zinck; Lund, Henrik

    2015-01-01

    In the transition towards a 100% renewable energy system, energy savings are essential. The possibility of energy savings through conservation or efficiency increases can be identified in, for instance, the heating and electricity sectors, in industry, and in transport. Several studies point...... to various optimal levels of savings in the different sectors of the energy system. However, these studies do not investigate the idea of energy savings being system dependent. This paper argues that such system dependency is critical to understand, as it does not make sense to analyse an energy saving...... without taking into account the actual benefit of the saving in relation to the energy system. The study therefore identifies a need to understand how saving methods may interact with each other and the system in which they are conducted. By using energy system analysis to do hourly simulation...

  13. Damping System for Torsional Resonances in Generator Shafts Using a Feedback Controlled Buffer Storage of Magnetic Energy at ASDEX Upgrade

    International Nuclear Information System (INIS)

    Kaesemann, C.-P.; Huart, M.; Mueller, P.; Sigalov, A.

    2006-01-01

    The electrical power and energy for ASDEX Upgrade (AUG) is provided by three separate pulsed networks based on flywheel generators. Major damages at couplings of the shaft of the synchronous generator EZ4 (220 MVA / 600 MWs) were discovered during a routine check. The damage can only be explained by torsional resonances in the generator shaft which are excited by active power transients from the converter loads. For generator protection, torque sensors were installed near the coupling between the flywheel and the rotor. They cause an early termination of plasma experiments if a predefined torque level is exceeded. These terminations limited the achievable plasma current flattop time of AUG significantly. Since a low natural damping of the torsional resonances was identified as a major cause of the phenomena observed, novel feedback controlled DC circuits were developed providing electromagnetic damping for the generator shafts in case of excitation. Each damping circuit consists of a DC choke, acting as a buffer storage of magnetic energy, fed by a thyristor converter. The current reference for the converter is derived from the torque sensor signals. This enables the choke current to alternate with the measured natural frequency of the shaft assembly. Thus, with proper phasing, torsional resonances in generator shaft systems weighing more than 100 tons can be damped with little additional power. Since April 2003, the damping circuits have been routinely operated during all plasma experiments. Despite the low damping power used, torsional resonances could be reduced to a value that avoids a trip signal from the torque sensors. This paper describes the results from analysing, designing and testing of the feedback controlled buffer storage of magnetic energy, representing an effective and low cost solution for damping torsional resonances in electric power systems. It will present the layout, analyse the results of measurements obtained during commissioning and

  14. The Smart Energy System

    DEFF Research Database (Denmark)

    Jurowetzki, Roman; Dyrelund, Anders; Hummelmose, Lars

    Copenhagen Cleantech Cluster has launched a new report, which provides an overview of Danish competencies relating to smart energy systems. The report, which is based on a questionnaire answered by almost 200 companies working with smart energy as well as a number of expert interviews, focuses on...... production, large scale solar heat, fuel cells, heat storage, waste incineration, among others, the report draws a picture of Denmark as a research and development hub for smart energy system solutions.......Copenhagen Cleantech Cluster has launched a new report, which provides an overview of Danish competencies relating to smart energy systems. The report, which is based on a questionnaire answered by almost 200 companies working with smart energy as well as a number of expert interviews, focuses...... on the synergies which are obtained through integration of the district heating and district cooling, gas, and electricity grid into a single smart energy system. Besides documenting the technology and innovation strengths that Danish companies possess particularly relating to wind, district heating, CHP...

  15. Hybrid spacecraft attitude control system

    OpenAIRE

    Renuganth Varatharajoo; Ramly Ajir; Tamizi Ahmad

    2016-01-01

    The hybrid subsystem design could be an attractive approach for futurespacecraft to cope with their demands. The idea of combining theconventional Attitude Control System and the Electrical Power System ispresented in this article. The Combined Energy and Attitude ControlSystem (CEACS) consisting of a double counter rotating flywheel assemblyis investigated for small satellites in this article. Another hybrid systemincorporating the conventional Attitude Control System into the ThermalControl...

  16. Autonomous renewable energy conversion system

    Energy Technology Data Exchange (ETDEWEB)

    Valtchev, V. [Technical University of Varna (Bulgaria). Dept. of Electronics; Bossche, A. van den; Ghijselen, J.; Melkebeek, J. [University of Gent (Belgium). Dept. of Electrical Power Engineering

    2000-02-01

    This paper briefly reviews the need for renewable power generation and describes a medium-power Autonomous Renewable Energy Conversion System (ARECS), integrating conversion of wind and solar energy sources. The objectives of the paper are to extract maximum power from the proposed wind energy conversion scheme and to transfer this power and the power derived by the photovoltaic system in a high efficiency way to a local isolated load. The wind energy conversion operates at variable shaft speed yielding an improved annual energy production over constant speed systems. An induction generator (IG) has been used because of its reduced cost, robustness, absence of separate DC source for excitation, easier dismounting and maintenance. The maximum energy transfer of the wind energy is assured by a simple and reliable control strategy adjusting the stator frequency of the IG so that the power drawn is equal to the peak power production of the wind turbine at any wind speed. The presented control strategy also provides an optimal efficiency operation of the IG by applying a quadratic dependence between the IG terminal voltage and frequency V {approx} f{sup 2}. For improving the total system efficiency, high efficiency converters have been designed and implemented. The modular principle of the proposed DC/DC conversion provides the possibility for modifying the system structure depending on different conditions. The configuration of the presented ARECS and the implementation of the proposed control algorithm for optimal power transfer are fully discussed. The stability and dynamic performance as well as the different operation modes of the proposed control and the operation of the converters are illustrated and verified on an experimental prototype. (author)

  17. Design of a Closed-Loop, Bidirectional Brain Machine Interface System With Energy Efficient Neural Feature Extraction and PID Control.

    Science.gov (United States)

    Liu, Xilin; Zhang, Milin; Richardson, Andrew G; Lucas, Timothy H; Van der Spiegel, Jan

    2017-08-01

    This paper presents a bidirectional brain machine interface (BMI) microsystem designed for closed-loop neuroscience research, especially experiments in freely behaving animals. The system-on-chip (SoC) consists of 16-channel neural recording front-ends, neural feature extraction units, 16-channel programmable neural stimulator back-ends, in-channel programmable closed-loop controllers, global analog-digital converters (ADC), and peripheral circuits. The proposed neural feature extraction units includes 1) an ultra low-power neural energy extraction unit enabling a 64-step natural logarithmic domain frequency tuning, and 2) a current-mode action potential (AP) detection unit with time-amplitude window discriminator. A programmable proportional-integral-derivative (PID) controller has been integrated in each channel enabling a various of closed-loop operations. The implemented ADCs include a 10-bit voltage-mode successive approximation register (SAR) ADC for the digitization of the neural feature outputs and/or local field potential (LFP) outputs, and an 8-bit current-mode SAR ADC for the digitization of the action potential outputs. The multi-mode stimulator can be programmed to perform monopolar or bipolar, symmetrical or asymmetrical charge balanced stimulation with a maximum current of 4 mA in an arbitrary channel configuration. The chip has been fabricated in 0.18 μ m CMOS technology, occupying a silicon area of 3.7 mm 2 . The chip dissipates 56 μW/ch on average. General purpose low-power microcontroller with Bluetooth module are integrated in the system to provide wireless link and SoC configuration. Methods, circuit techniques and system topology proposed in this work can be used in a wide range of relevant neurophysiology research, especially closed-loop BMI experiments.

  18. Small-signal stability analysis for two-area interconnected power system with load frequency controller in coordination with FACTS and energy storage device

    Directory of Open Access Journals (Sweden)

    Ravi Shankar

    2016-06-01

    Full Text Available This paper deals with the modelling and small signal stability analysis for the two areas interconnected power system using a load frequency controller. The eigenvalues and the participation factor analysis are used to examine the small signal stability and contribution of different states in a particular eigenvalue of the system, respectively. A load frequency controller is designed to stabilize the frequency deviations which occur due to the small perturbation in the system. In this paper, the proposed control scheme consists of an integral controller in coordination with the Redox Flow Energy Storage System (RFESS and the Static Synchronous Series Compensator (SSSC. The dynamic responses of the overall system have been improved by the proposed controller, which is also verified with the help of eigenvalue and participation factor analysis. This analysis shows that overall system oscillation has been reduced through a proposed controller.

  19. Nonlinear dynamics and control strategies: On a energy harvester vibrating system with a linear form to non-ideal motor torquet

    Directory of Open Access Journals (Sweden)

    de Pontes B. R.

    2012-07-01

    Full Text Available In this paper, we deal with the research of a vibrating model of an energy harvester device, including the nonlinearities in the model of the piezoelectric coupling and the non-ideal excitation. We show, using numerical simulations, in the analysis of the dynamic responses, that the harvested power is influenced by non-linear vibrations of the structure. Chaotic behavior was also observed, causing of the loss of energy throughout the simulation time. Using a perturbation technique, we find an approximate analytical solution for the non-ideal system. Then, we apply both two control techniques, to keep the considered system, into a stable condition. Both the State Dependent Ricatti Equation (SDRE control as the feedback control by changing the energy of the oscillator, were efficient in controlling of the considered non-ideal system.

  20. Energy policies and renewable energy systems monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Di Nisio, Attilio; Savino, Mario; Spadavecchia, Maurizio [Electrical and Electronic Measurements Laboratory, Dept. of Electrical and Electronic Engineering - Politecnico di Bari, Bari (Italy)], e-mails: dinisio@misure.poliba.it, savino@misure.poliba.it, spadavecchia@misure.poliba.it

    2011-07-01

    Full text: The global energy crisis is forcing every country worldwide to review its policies on energy. The environmental disaster at Japan's Fukushima Daiichi nuclear power plant has accelerated this process. Many people around the world are citing the disaster as evidence that nuclear power would endanger the survival of mankind on earth and should be banned. Today we need to focus more substantially on energy saving, especially using smart devices with low power consumption. We have also to review the approach to the exploitation of energy and move from a philosophy 'from the ground to the subsurface' to another 'from the earth to the sun'. This paper highlights the increasing importance of solar power in meeting energy needs while achieving security of supply and minimising carbon dioxide (CO{sub 2}) emissions. It deals also with the development of solar power plants, which require a supervisory control system that improves their efficiency and reliability. (author)