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Sample records for active power control

  1. Active Power Filter Using Predicted Current Control

    Xiaojie, Y.; Pivoňka, P.; Valouch, Viktor

    2001-01-01

    Roč. 46, č. 1 (2001), s. 41-50. ISSN 0001-7043 Institutional research plan: CEZ:AV0Z2057903 Keywords : active power filter * control strategy Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering

  2. Active Power Controls from Wind Power: Bridging the Gaps

    Ela, E.; Gevorgian, V.; Fleming, P.; Zhang, Y. C.; Singh, M.; Muljadi, E.; Scholbrook, A.; Aho, J.; Buckspan, A.; Pao, L.; Singhvi, V.; Tuohy, A.; Pourbeik, P.; Brooks, D.; Bhatt, N.

    2014-01-01

    This paper details a comprehensive study undertaken by the National Renewable Energy Laboratory, Electric Power Research Institute, and the University of Colorado to understand how the contribution of wind power providing active power control (APC) can benefit the total power system economics, increase revenue streams, improve the reliability and security of the power system, and provide superior and efficient response while reducing any structural and loading impacts that may reduce the life of the wind turbine or its components. The study includes power system simulations, control simulations, and actual field tests using turbines at NREL's National Wind Technology Center (NWTC). The study focuses on synthetic inertial control, primary frequency control, and automatic generation control, and analyzes timeframes ranging from milliseconds to minutes to the lifetime of wind turbines, locational scope ranging from components of turbines to large wind plants to entire synchronous interconnections, and additional topics ranging from economics to power system engineering to control design.

  3. Power system damping - Structural aspects of controlling active power

    Samuelsson, O.

    1997-04-01

    Environmental and economical aspects make it difficult to build new power lines and to reinforce existing ones. The continued growth in demand for electric power must therefore to a great extent be met by increased loading of available lines. A consequence is that power system damping is reduced, leading to a risk of poorly damped power oscillations between the generators. This thesis proposes the use of controlled active loads to increase damping of such electro-mechanical oscillations. The focus is on structural aspects of controller interaction and of sensor and actuator placement. On-off control based on machine frequency in a single machine infinite bus system is analysed using energy function analysis and phase plane plots. An on-off controller with estimated machine frequency as input has been implemented. At a field test it damped oscillations of a 0.9 MW hydro power generator by controlling a 20kW load. The linear analysis uses two power system models with three and twenty-three machines respectively. Each damper has active power as output and local bus frequency or machine frequency as input. The power system simulator EUROSTAG is used both for generation of the linearized models and for time simulations. Measures of active power mode controllability and phase angle mode observability are obtained from the eigenvectors of the differential-algebraic models. The geographical variation in the network of these quantities is illustrated using the resemblance to bending modes of flexible mechanical structures. Eigenvalue sensitivities are used to determine suitable damper locations. A spring-mass equivalent to an inter-area mode provides analytical expressions, that together with the concept of impedance matching explain the structural behaviour of the power systems. For large gains this is investigated using root locus plots. 64 refs, 99 figs, 20 tabs

  4. Prediction control of active power filters

    王莉娜; 罗安

    2003-01-01

    A prediction method to obtain harmonic reference for active power filter is presented. It is a new use ofthe adaptive predictive filter based on FIR. The delay inherent in digital controller is successfully compensated by u-sing the proposed method, and the computing load is not very large compared with the conventional method. Moreo-ver, no additional hardware is needed. Its DSP-based realization is also presented, which is characterized by time-va-riant rate sampling, quasi synchronous sampling, and synchronous operation among the line frequency, PWM gener-ating and sampling in A/D unit. Synchronous operation releases the limitation on PWM modulation ratio and guar-antees that the electrical noises resulting from the switching operation of IGBTs do not interfere with the sampledcurrent. The simulation and experimental results verify the satisfactory performance of the proposed method.

  5. Indirect control of a single-phase active power filter

    Mihai CULEA

    2006-12-01

    Full Text Available The control of shunt active power filters using PWM inverters consists in generating a reference by separating, using different methods, the harmonics to be eliminated. The methods used are time-consuming and need dedicated control and signal processing equipments. To avoid these setbacks a new method is proposed in the paper. The active power filter is a current PWM rectifier with voltage output and with a capacitor on the DC side. The PWM rectifier is controlled so that the sum of its current and the load’s current is a sinusoid. The control block as well as simulation results are presented.

  6. A New Multilevel Active Power Filter Using Switches Meticulously Controlled

    Zoubir Zahzouh

    2015-03-01

    Full Text Available Shunt active power filter based on multilevel inverter is used to compensate the power factor and to delete the harmonics. This one permits to reduce the inverse voltages applied to the filter switches and their switching frequencies. Nevertheless, the high number of used switches requires a complicated controller and increases the switching losses; where the necessity of finding another resolution system. In this work a new topology of multilevel inverter is proposed as a shunt active power filter using two IGBT transistors in series of opposite sense meticulously controlled by a parallel control algorithm, with the concept of reduced number of six switches which are able to create five levels of the output voltage. This system substute the classical system of eight switches. The harmonic currents identification is carried out using the instantaneous active and reactive power method. The simulation is performed using Matlab/Simulink. The obtained results show that the filtering performances are well enhanced.

  7. The Control of Transmitted Power in an Active Isolation System

    Elliott, S.J.; Gardonio, P.; Pinnington, R.J.;

    1997-01-01

    more practical control strategy appears to be to minimise the weighted sum of squared forces and velocities below the mounts, which gives near-optimal performance in simulations. These theoretical results are supported by experiments with a real-time control system. The actuator and sensor requirements...... distributed active mounts, and these models can be connected together to produce an overall theoretical description of a realistic active isolation system. Total transmitted power has been found to be an excellent criterion to quantify the effect of various control strategies in this model in which the...... contributions to the transmitted power in the various degrees of freedom can be clearly understood. It has also been found, however, that an active control system which minimises a practical estimate of transmitted power, calculated from the product of the axial forces and velocities under the mounts, can give...

  8. Design and control of hybrid active power filters

    Lam, Chi-Seng

    2014-01-01

    Design and Control of Hybrid Active Power Filters presents an overview of the current quality problems and their compensators. To get a balance between the system cost and performance, hybrid active power filters (HAPFs) are valuable. The book presents the coverage of resonance phenomena prevention capability, filtering performance and system robustness analysis of HAPF; nonlinear inverter current slope characteristics and their linear operation region requirement analysis of the hysteresis PWM for the HAPF; minimum inverter capacity design procedure of HAPF, adaptive dc-link voltage controller for the HAPF and the real design example of a 220V 10kVA HAPF, in which the system performance analysis method, minimum dc voltage deduction concept and adaptive dc voltage idea can be further extended into the other active compensators, such as APF, static synchronous compensator STATCOM, etc. This book will benefit researchers, graduate students, and electrical power engineers in the field of power-quality compensati...

  9. Model based active power control of a wind turbine

    Mirzaei, Mahmood; Soltani, Mohsen; Poulsen, Niels Kjølstad;

    2014-01-01

    In recent decades there has been increasing interest in green energies, of which wind energy is one of the most important. Wind turbines are the most common wind energy conversion systems and are hoped to be able to compete with traditional power plants in near future. This demands better...... technology to increase competitiveness of the wind power plants. One way to increase competitiveness of wind power plants is to offer grid services (also called ancillary services) that are normally offered by traditional power plants. One of the ancillary services is called reserve power. There are instants...... in the electricity market that selling the reserve power is more profitable than producing with the full capacity. Therefore wind turbines can be down-regulated and sell the differential capacity as the reserve power. In this paper we suggest a model based approach to control wind turbines for active...

  10. Advanced nonlinear control of three phase series active power filter

    Abouelmahjoub Y.

    2014-01-01

    Full Text Available The problem of controlling three-phase series active power filter (TPSAPF is addressed in this paper in presence of the perturbations in the voltages of the electrical supply network. The control objective of the TPSAPF is twofold: (i compensation of all voltage perturbations (voltage harmonics, voltage unbalance and voltage sags, (ii regulation of the DC bus voltage of the inverter. A controller formed by two nonlinear regulators is designed, using the Backstepping technique, to provide the above compensation. The regulation of the DC bus voltage of the inverter is ensured by the use of a diode bridge rectifier which its output is in parallel with the DC bus capacitor. The Analysis of controller performances is illustrated by numerical simulation in Matlab/Simulink environment.

  11. A predictive control algorithm for an active three-phase power filter

    R.V. Vlasenko; Bialobrzeski, O. V.

    2014-01-01

    The paper deals with grid connection circuits for active filters, structures of active power filter control systems, and methods based on full capacity components determination. The existing structures of active power filter control and control algorithm adjustment for valve commutation loss reduction are analyzed. A predictive control algorithm for an active three-phase power filter is introduced.

  12. Distributed Model Predictive Control of A Wind Farm for Optimal Active Power Control

    Zhao, Haoran; Wu, Qiuwei; Guo, Qinglai; Sun, Hongbin; Xue, Yusheng

    2015-01-01

    This paper presents a dynamic discrete-time Piece- Wise Affine (PWA) model of a wind turbine for the optimal active power control of a wind farm. The control objectives include both the power reference tracking from the system operator and the wind turbine mechanical load minimization. Instead of...

  13. Active Power Filter: Review of Converter Topologies and Control Strategies

    SARIBULUT, Lütfü; Ahmet TEKE; MERAL, M. EMIN; Tumay, Mehmet

    2011-01-01

    Decrease in the cost of power electronic devices and improvement in the efficiency of both power converters and energy storage components have increased the applicability of new technological solutions such as Custom Power (CP) and Flexible AC Transmission Systems (FACTS) Devices. Active Power Filter (APF) is one of the CP devices and can mitigate harmonics, reactive power and unbalanced load currents originating from load side. In this study, a comprehensive review of APF studies, the advant...

  14. Adaptive Current Control with PI-Fuzzy Compound Controller for Shunt Active Power Filter

    Juntao Fei

    2013-01-01

    Full Text Available An adaptive control technology and PI-fuzzy compound control technology are proposed to control an active power filter (APF. AC side current compensation and DC capacitor voltage tracking control strategy are discussed and analyzed. Model reference adaptive controller for the AC side current compensation is derived and established based on Lyapunov stability theory; proportional and integral (PI fuzzy compound controller is designed for the DC side capacitor voltage control. The adaptive current controller based on PI-fuzzy compound system is compared with the conventional PI controller for active power filter. Simulation results demonstrate the feasibility and satisfactory performance of the proposed control strategies. It is shown that the proposed control method has an excellent dynamic performance such as small current tracking error, reduced total harmonic distortion (THD, and strong robustness in the presence of parameters variation and nonlinear load.

  15. Power control of water reactors using nitrogen 16 activity measurements

    At the Grenoble Nuclear Research Centre, the open-core swimming pool reactors Melusine (2 MW) and Siloe (15 MW) are controlled at a constant overall power using nitrogen-16 channels. The conventional linear control channels react instantaneously to the rapid power fluctuations, this being necessary for the safety of the reactors, but their power indications are erroneous since they are affected by local deformations of the thermal flux caused by the compensation movements of the control rods. The nitrogen-16 channels on the other hand give an indication of the overall power proportional to the mean fission flux and independent of the rod movements, but their response time is 15 seconds, A constant overall power control is thus possible by a slow correction of the reference signal given by the automatic control governed by thu linear channels by means of a correction term given by the 'N-16' channels: This is done automatically in Melusine and manually in Siloe. (authors)

  16. Distributed Model Predictive Control of A Wind Farm for Optimal Active Power Control

    Zhao, Haoran; Wu, Qiuwei; Guo, Qinglai;

    2015-01-01

    This paper presents a dynamic discrete-time Piece- Wise Affine (PWA) model of a wind turbine for the optimal active power control of a wind farm. The control objectives include both the power reference tracking from the system operator and the wind turbine mechanical load minimization. Instead of...... partial linearization of the wind turbine model at selected operating points, the nonlinearities of the wind turbine model are represented by a piece-wise static function based on the wind turbine system inputs and state variables. The nonlinearity identification is based on the clustering-based algorithm...... other advanced optimal control applications of a wind farm....

  17. Nuclear Power Plant Control and Instrumentation activities in Finland

    Finland has achieved some remarkable achievements in nuclear power production. Existing four plants have some of the best operating records in the world - high capacity factors, low occupational doses and short refuelling outages. Although public opinion was strongly turned against nuclear power after Chernobyl accident, and no decisions for new nuclear plants can be made before next elections in 1991, the nuclear option is still open. Utility companies are maintaining readiness to start new construction immediately after a positive political decision is made. One important component of the good operation history of the Finnish nuclear power plants is connected to the continuous research, development, modification and upgrading work, which is proceeding in Finland. In the following a short description is given on recent activities related to the I and C-systems of the nuclear power plants. (author). 2 tabs

  18. Feedback Linearization Control of a Shunt Active Power Filter Using a Fuzzy Controller

    Tianhua Li

    2013-09-01

    Full Text Available In this paper, a novel feedback linearization based sliding mode controlled parallel active power filter using a fuzzy controller is presented in a three-phase three-wire grid. A feedback linearization control with fuzzy parameter self-tuning is used to implement the DC side voltage regulation while a novel integral sliding mode controller is applied to reduce the total harmonic distortion of the supply current. Since traditional unit synchronous sinusoidal signal calculation methods are not applicable when the supply voltage contains harmonics, a novel unit synchronous sinusoidal signal computing method based on synchronous frame transforming theory is presented to overcome this disadvantage. The simulation results verify that the DC side voltage is very stable for the given value and responds quickly to the external disturbance. A comparison is also made to show the advantages of the novel unit sinusoidal signal calculating method and the super harmonic treatment property of the designed active power filter.

  19. Nuclear Power Plant Control and Instrumentation activities in Czechoslovakia

    After giving a survey of the Czechoslovak nuclear power plants a description of I and C systems of the operating plants is presented together with a brief outlook for future developments to be implemented at plants which are under construction. Special attention is paid to the adopted techniques for power distribution investigation and control in the WWER 1000 reactor core in the case of load changes. Basic futures of the in-core measurement systems are outlined. Measures implemented in the I and C systems of the operating units to improve their performance are described. Information on the country's approach to NPP personnel training and training aids usage as well as information on development work in the area of surveillance and monitoring systems completes the paper. (author). 9 refs, 1 tab

  20. PI, FUZZY and ANFIS Control of 3-Phase Shunt Active Power Filter

    Brahmaiah.routhu

    2013-06-01

    Full Text Available this paper describes control of 3-phase shunt active filter by using PI, fuzzy and ANFIS controls to improve the power quality and reactive power compensation and harmonic current compensation due to nonlinear loads. The controller is capable of controlling the DC capacitor voltage capable of reference source current. Hysteresis control is used to control the current in PWM inverter. The simulation results reveals that comparative study of all this results shows the advantage anddisadvantages of 3 control strategies.

  1. Superior decoupled control of active and reactive power for three-phase voltage source converters

    RAHBARIMAGHAM, HESAM; AMIRI, ERFAN MAALI; VAHIDI, Behrooz; GHAREHPETIAN, GEVORG BABAMALEK; Abedi, Mehrdad

    2015-01-01

    This paper presents an active-reactive power control strategy for voltage source converters (VSCs) based on derivation of the direct and quadrature components of the VSC output current. The proposed method utilizes a multivariable proportional-integral controller and provides almost completely decoupled control capability of the active and reactive power with almost full disturbance rejection due to step changes in the power exchanged between the VSC and the grid. It also imposes fast transie...

  2. Development of Control Structure for Hybrid Wind Generators with Active Power Capability

    Mehdi Niroomand

    2014-01-01

    Full Text Available A hierarchical control structure is proposed for hybrid energy systems (HES which consist of wind energy system (WES and energy storage system (ESS. The proposed multilevel control structure consists of four blocks: reference generation and mode select, power balancing, control algorithms, and switching control blocks. A high performance power management strategy is used for the system. Also, the proposed system is analyzed as an active power filter (APF with ability to control the voltage, to compensate the harmonics, and to deliver active power. The HES is designed with parallel DC coupled structure. Simulation results are shown for verification of the theoretical analysis.

  3. Tutorial of Wind Turbine Control for Supporting Grid Frequency through Active Power Control: Preprint

    Aho, J.; Buckspan, A.; Laks, J.; Fleming, P.; Jeong, Y.; Dunne, F.; Churchfield, M.; Pao, L.; Johnson, K.

    2012-03-01

    As wind energy becomes a larger portion of the world's energy portfolio and wind turbines become larger and more expensive, wind turbine control systems play an ever more prominent role in the design and deployment of wind turbines. The goals of traditional wind turbine control systems are maximizing energy production while protecting the wind turbine components. As more wind generation is installed there is an increasing interest in wind turbines actively controlling their power output in order to meet power setpoints and to participate in frequency regulation for the utility grid. This capability will be beneficial for grid operators, as it seems possible that wind turbines can be more effective at providing some of these services than traditional power plants. Furthermore, establishing an ancillary market for such regulation can be beneficial for wind plant owner/operators and manufacturers that provide such services. In this tutorial paper we provide an overview of basic wind turbine control systems and highlight recent industry trends and research in wind turbine control systems for grid integration and frequency stability.

  4. Optimum PI Controllers of Active Power Filters for Harmonic Voltage Mitigation in Multibus Industrial Power Systems

    Tlustý, J.; Valouch, Viktor

    Palma de Mallorca: EA4EPQ, 2006, s. 1-5. ISBN 84-609-6604-6. [nternational Conference on Renewable Energies and Power Quality (ICREPQ'06). Palma de Mallorca (ES), 05.04.2006-07.04.2006] Institutional research plan: CEZ:AV0Z20570509 Keywords : active power filter * industrial power system * harmonic voltage mitigation Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering

  5. Wind Farm Active Power Dispatch for Output Power Maximizing Based on a Wind Turbine Control Strategy for Load Minimizing

    Zhang, Baohua; Hu, Weihao; Hou, Peng;

    2015-01-01

    Inclusion of the wake effect in the wind farm control design (WF) can increase the total captured power by wind turbines (WTs), which is usually implemented by derating upwind WTs. However, derating the WT without a proper control strategy will increase the structural loads, caused by operation in...... stall mode. Therefore, the WT control strategy for derating operation should be considered in the attempt at maximizing the total captured power while reducing structural loads. Moreover, electrical power loss on the transmission system inside a WF is also not negligible for maximizing the total output...... power of the WF. In this paper, an optimal active power dispatch strategy based on a WT derating strategy and considering the transmission loss is proposed for maximizing the total output power. The active power reference of each WT is chosen as the optimization variable. A partial swarm optimizing...

  6. Control System Design of Shunt Active Power Filter Based on Active Disturbance Rejection and Repetitive Control Techniques

    Le Ge

    2014-01-01

    Full Text Available To rely on joint active disturbance rejection control (ADRC and repetitive control (RC, in this paper, a compound control law for active power filter (APF current control system is proposed. According to the theory of ADRC, the uncertainties in the model and from the circumstance outside are considered as the unknown disturbance to the system. The extended state observer can evaluate the unknown disturbance. Next, RC is introduced into current loop to improve the steady characteristics. The ADRC is used to get a good dynamic performance, and RC is used to get a good static performance. A good simulation result is got through choosing and changing the parameters, and the feasibility, adaptability, and robustness of the control are testified by this result.

  7. Control of high power IGBT modules in the active region for fast pulsed power converters

    Cravero, J M; Garcia Retegui, R; Maestri, S; Uicich, G

    2014-01-01

    At CERN, fast pulsed power converters are used to supply trapezoidal current in different magnet loads. These converters perform output current regulation by using a high power IGBT module in its ohmic region. This paper presents a new strategy for pulsed current control applications using a specifically designed IGBT driver.

  8. Active and reactive power control of a current-source PWM-rectifier using space vectors

    Salo, M.; Tuusa, H. [Tampere University of Technology (Finland). Department of Electrical Engineering, Power Electronics

    1997-12-31

    In this paper the current-source PWM-rectifier with active and reactive power control is presented. The control system is realized using space vector methods. Also, compensation of the reactive power drawn by the line filter is discussed. Some simulation results are shown. (orig.) 8 refs.

  9. THREE-PHASE ACTIVE POWER FILTER CONTROLLER FOR BALANCED AND UNBALANCED NON-LINEAR LOAD

    G.NAGESWARA RAO

    2010-09-01

    Full Text Available The active power filter produces equal but opposite harmonic currents to the point of connection with the nonlinear load. This results in a reduction of the original distortion and correction of the power factor. A threephase insulated gate bipolar transistor based current controlled voltage source inverter with a dc bus capacitor is used as an active filter. The firing pulses to the shunt active filter will be generated by using sine PWM method. The models for three-phase active power filter controller for balanced and unbalanced non-linear load is made and is simulated using Matlab/simulink software.

  10. Active and recreative power control in the presence of types of static VAR compensators (SVC)

    Tobnaghi, Davoud Mostafa [Department of Electrical Engineering, Parsabad Moghan Branch, Islamic Azad University (Iran, Islamic Republic of)], email: dmostafa@iaupmogan.ac.ir; Najafi, Atabak; Sadeghi Nasrabadi, Jafar [Department of Electrical Engineering, Germi Branch, Islamic Azad University (Iran, Islamic Republic of)], email: Jafarsadegi64@gmail.com, email: atabak_najafi@yahoo.com; Karimi, Mohammad; Farhadi, Payam [Department of Electrical Engineering, Parsabad Moghan Branch, Islamic Azad University (Iran, Islamic Republic of)], email: mohammadkarimi62@gmail.com, email: pfarhadi@iaupmogan.ac.ir

    2011-07-01

    This paper investigates the effects of various types of Static Var Compensators, a particular sort of FACTS (Flexible AC Transmission System), on active and reactive power flow control with the purpose of increasing the capacity of existing electrical transmission systems rather than having to build new ones. The prime reasons are both economic and environmental: deregulation in the electrical market increases the need to be competitive while ensuring security and operating within various physical limitations related to thermal capacity and stability of voltage in transmission lines. The development of high power semiconductor devices makes it now possible to use these in power systems. After an overall review of SVCs, six were selected, analysed, and classified in order from lowest to highest power flow control range. It was also concluded that with the use of SVCs there is more fluctuation in reactive power control and almost no oscillation in active power control.

  11. Review of Active and Reactive Power Sharing Strategies in Hierarchical Controlled Microgrids

    Han, Yang; Li, Hong; Shen, Pan;

    2016-01-01

    Microgrids consist of multiple parallel-connected distributed generation (DG) units with coordinated control strategies, which are able to operate in both grid-connected and islanded mode. Microgrids are attracting more and more attention since they can alleviate the stress of main transmission...... systems, reduce feeder losses, and improve system power quality. When the islanded microgrids are concerned, it is important to maintain system stability and achieve load power sharing among the multiple parallel-connected DG units. However, the poor active and reactive power sharing problems due to the...... paper for active power sharing. Moreover, nonlinear and unbalanced loads could further affect the reactive power sharing when regulating the active power, and it is difficult to share the reactive power accurately only by using the enhanced virtual impedance method. Therefore, the hierarchical control...

  12. Active Power and DC-link Voltage Coordinative Control for Cascaded DC-AC Converter with Bidirectional Power Application

    Tian, Yanjun; Chen, Zhe; Deng, Fujin;

    2015-01-01

    Two stage cascaded converters are widely used in DC/AC hybrid systems to achieve the bidirectional power transmission. The topology of dual active bridge cascaded with inverter (DABCI) is commonly used in this application. This paper proposes a coordinative control method for DABCI and it’s able to...... reduce the DC-link voltage fluctuation between the DAB and inverter, then reduce the stress on the switching devices, as well as improve the system dynamic performance. In the proposed control method, the DAB and inverter are coordinated to control the DC-link voltage and the power, and this...... responsibility sharing control can effectively suppress the impact of the power variation on the DC-link voltage, without sacrificing stability. The proposed control method is also effective for DABCI in unidirectional power transmission. The effectiveness of the propose control has been validated by both...

  13. Cooperative Control of Active Power Filters in Power Systems without Mutual Communication

    Tlustý, J.; Škramlík, Jiří; Švec, J.; Valouch, Viktor

    2010-01-01

    Roč. 2010, č. 517184 (2010), s. 1-13. ISSN 1024-123X R&D Projects: GA AV ČR IAA200760703 Institutional research plan: CEZ:AV0Z20570509 Keywords : active power filter * power system * wireless cooperation Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering Impact factor: 0.689, year: 2010 http://www.hindawi.com/journals/mpe/2010/517184.html

  14. Active Harmonic Filtering Using Current-Controlled, Grid-Connected DG Units With Closed-Loop Power Control

    Jinwei He,; Yun Wei Li,; Blaabjerg, Frede; Xiongfei Wang,

    2014-01-01

    The increasing application of nonlinear loads may cause distribution system power quality issues. In order to utilize distributed generation (DG) unit interfacing converters to actively compensate harmonics, this paper proposes an enhanced current control approach, which seamlessly integrates system harmonic mitigation capabilities with the primary DG power generation function. As the proposed current controller has two well-decoupled control branches to independently control fundamental and ...

  15. Impact of thermostatically controlled loads' demand response activation on aggregated power: A field experiment

    Lakshmanan, Venkatachalam; Marinelli, Mattia; Kosek, Anna Magdalena;

    2015-01-01

    This paper describes the impacts of different types of DR (demand response) activation on TCLs' (thermostatically controlled loads) aggregated power. The different parties: power system operators, DR service providers (or aggregators) and consumers, have different objectives in relation to DR...... activation. The outcome of this experimental study quantifies the actual flexibility of household TCLs and the consequence for the different parties with respect to power behaviour. Each DR activation method adopts different scenarios to meet the power reduction, and has different impacts on the parameters....... The experiments are conducted with real domestic refrigerators representing TCL. Activating refrigerators for DR with a delay reduces the ISE (integral square error) in power limitation by 28.46%, overshoot by 7.69%. The delay in refrigerator activation causes reduction in power ramp down rate by 39...

  16. Design and control of LCL-filter with active damping for Active Power Filter

    Zeng, Guohong; Rasmussen, Tonny Wederberg; Ma, L;

    2010-01-01

    In the application of shunt Active Power Filter (APF) to compensate nonlinear load's harmonic, reactive and negative sequence current, it is more effective to use a LCL-filter than an L-filter as an interface between the Voltage Source Converter (VSC) and grid. In this paper, a designing procedure...... of LCL-filter for APF is introduced, which is aimed for simplified the implementation. To suppress the resonance that may be excited in the system, which brings in stability problems, an active damping control strategy using the current feed-back of the filter capacitor is adopted. By selecting two equal...... or similar inductances, the filter designing become more simple and effective, meanwhile the capacitance requirement is minimized. A pole-zero automatic cancellation phenomenon is discussed in this paper, which can be applied to simplify the current regulator designing. The tuning method is presented, based...

  17. Mitigation of Wind Power Fluctuation by Active Current Control of Variable Speed Wind Turbines

    Zhang, Yunqian; Chen, Zhe; Hu, Weihao; Cheng, Ming

    2013-01-01

    Wind shear and tower shadow are the sources of power fluctuation of grid connected wind turbines during continuous operation. This paper presents a simulation model of a MW-level doubly fed induction generator (DFIG) based variable speed wind turbine with a partial-scale back-to-back power...... converter in Simulink. A simple and effective method of wind power fluctuations mitigation by active current control of DFIG is proposed. It smoothes the generator output active power oscillations by adjusting the active current of the DFIG, such that the power oscillation is stored as the kinetic energy of...... the wind turbine. The simulations are performed on the NREL 1.5MW upwind reference wind turbine model. The simulation results are presented and discussed to demonstrate the validity of the proposed control method....

  18. Active control of radiated sound power from a baffled, rectangular panel

    Mørkholt, Jakob

    Active control of radiated sound power from a rectangular baffled panel by minimisation of an accurate power estimate, using piezoceramic actuators, has been investigated. Computer simulations have shown that minimising a power estimate obtained by discretised integration of the far field intensity...... with an array of eleven microphones in front of the panel, is very close to minimising the actual radiated sound power. Practical experiments where such an array estimate has been minimised using the filtered X LMS algorithm have shown that substantial reductions of radiated sound power can be obtained...

  19. Active control of radiated sound power from a baffled, rectangular panel

    Mørkholt, Jakob

    1996-01-01

    Active control of radiated sound power from a rectangular baffled panel by minimisation of an accurate power estimate, using piezoceramic actuators, has been investigated. Computer simulations have shown that minimising a power estimate obtained by discretised integration of the far field intensity...... with an array of eleven microphones in front of the panel, is very close to minimising the actual radiated sound power. Practical experiments where such an array estimate has been minimised using the filtered X LMS algorithm have shown that substantial reductions of radiated sound power can be obtained over...

  20. Active Power Control of Wind Turbines for Ancillary Services: A Comparison of Pitch and Torque Control Methodologies

    Aho, Jacob; Fleming, Paul; Pao, Lucy Y.

    2016-08-01

    As wind energy generation becomes more prevalent in some regions, there is increased demand for wind power plants to provide ancillary services, which are essential for grid reliability. This paper compares two different wind turbine control methodologies to provide active power control (APC) ancillary services, which include derating or curtailing power generation, providing automatic generation control (AGC), and providing primary frequency control (PFC). The torque APC controller provides all power control through the power electronics whereas the pitch APC controller uses the blade pitch actuators as the primary means of power control. These controllers are simulated under various wind conditions with different derating set points and AGC participation levels. The metrics used to compare their performance are the damage equivalent loads (DELs) induced on the structural components and AGC performance metrics, which are used to determine the payments for AGC services by system operators in the United States. The simulation results show that derating the turbine reduces structural loads for both control methods, with the APC pitch control providing larger reductions in DELs, lower AGC performance scores, and higher root-mean-square pitch rates. Providing AGC increases the structural loads when compared to only derating the turbine, but even the AGC DELs are generally lower than those of the baseline control system. The torque APC control methodology also allows for more sustained PFC responses under certain derating conditions.

  1. Active Participation of Air Conditioners in Power System Frequency Control Considering Users’ Thermal Comfort

    Rongxiang Zhang; Xiaodong Chu; Wen Zhang; Yutian Liu

    2015-01-01

    Air conditioners have great potential to participate in power system frequency control. This paper proposes a control strategy to facilitate the active participation of air conditioners. For each air conditioner, a decentralized control law is designed to adjust its temperature set point in response to the system frequency deviation. The decentralized control law accounts for the user’s thermal comfort that is evaluated by a fuzzy algorithm. The aggregation of air conditioners’ response is c...

  2. Computational Fluid Dynamics Simulation Study of Active Power Control in Wind Plants

    Fleming, Paul; Aho, Jake; Gebraad, Pieter; Pao, Lucy; Zhang, Yingchen

    2016-08-01

    This paper presents an analysis performed on a wind plant's ability to provide active power control services using a high-fidelity computational fluid dynamics-based wind plant simulator. This approach allows examination of the impact on wind turbine wake interactions within a wind plant on performance of the wind plant controller. The paper investigates several control methods for improving performance in waked conditions. One method uses wind plant wake controls, an active field of research in which wind turbine control systems are coordinated to account for their wakes, to improve the overall performance. Results demonstrate the challenge of providing active power control in waked conditions but also the potential methods for improving this performance.

  3. Control strategies of active filters in the context of power conditioning

    Dan, Stan George; Benjamin, Doniga Daniel; Magureanu, R.;

    2005-01-01

    Active Power Filters have been intensively explored in the past decade. Various topologies and control schemes have been documented aiming at reducing the cost and improving the performance of the compensation system. Hybrid active filters inherit the efficiency of passive filters and the improved...

  4. Active harmonic filtering using current-controlled, grid-connected DG units with closed-loop power control

    He, Jinwei; Li, Yun Wei; Blaabjerg, Frede;

    2014-01-01

    The increasing application of nonlinear loads may cause distribution system power quality issues. In order to utilize distributed generation (DG) unit interfacing converters to actively compensate harmonics, this paper proposes an enhanced current control approach, which seamlessly integrates...... voltage detection are not necessary for the proposed harmonic compensation method. Moreover, a closed-loop power control scheme is employed to directly derive the fundamental current reference without using any phase-locked loops (PLL). The proposed power control scheme effectively eliminates the impacts...... of steady-state fundamental current tracking errors in the DG units. Thus, an accurate power control is realized even when the harmonic compensation functions are activated. In addition, this paper also briefly discusses the performance of the proposed method when DG unit is connected to a grid with...

  5. Power Controller

    1982-01-01

    The device called the Power Factor Controller (PFC) offers exceptional energy conservation potential by virtue of its ability to sense shifts in the relationship between voltage and current flow, and to match them with the motor's need. Originating from the solar heating/cooling program, the PFC senses a light load, it cuts the voltage level to the minimum needed which in turn reduces current flow and heat loss. Laboratory tests showed that the PFC could reduce power used by six to eight percent under normal motor loads, and as much as 65 percent when the motor was idling. Over 150 companies have been granted NASA licenses for commercial use of this technology. One system that utilizes this technology is the Vectrol Energy System, (VES) produced by Vectrol, Inc. a subsidiary of Westinghouse. The VES is being used at Woodward & Lothrop, on their escalators. Energy use is regulated according to how many people are on the escalator at any time. It is estimated that the energy savings are between 30 to 40 percent.

  6. Active Vibration Control for Helicopter Interior Noise Reduction Using Power Minimization

    Mendoza, J.; Chevva, K.; Sun, F.; Blanc, A.; Kim, S. B.

    2014-01-01

    This report describes work performed by United Technologies Research Center (UTRC) for NASA Langley Research Center (LaRC) under Contract NNL11AA06C. The objective of this program is to develop technology to reduce helicopter interior noise resulting from multiple gear meshing frequencies. A novel active vibration control approach called Minimum Actuation Power (MAP) is developed. MAP is an optimal control strategy that minimizes the total input power into a structure by monitoring and varying the input power of controlling sources. MAP control was implemented without explicit knowledge of the phasing and magnitude of the excitation sources by driving the real part of the input power from the controlling sources to zero. It is shown that this occurs when the total mechanical input power from the excitation and controlling sources is a minimum. MAP theory is developed for multiple excitation sources with arbitrary relative phasing for single or multiple discrete frequencies and controlled by a single or multiple controlling sources. Simulations and experimental results demonstrate the feasibility of MAP for structural vibration reduction of a realistic rotorcraft interior structure. MAP control resulted in significant average global vibration reduction of a single frequency and multiple frequency excitations with one controlling actuator. Simulations also demonstrate the potential effectiveness of the observed vibration reductions on interior radiated noise.

  7. Active Power Control Simulation Platform Research of Wind Farm Based on Multi-Agent

    Liu Xingjie

    2015-01-01

    Full Text Available The realization of the automation, routinization and intelligentization of dispatch control in wind farms is the key to the integration of wind farms into power grid management system. Active power regulate and control system in wind farms has increasingly high demand on timeliness, but at present this system is mostly equipped with centralized unidirectional control with poor timeliness and low utilization ratio for wind energy resources. The characteristics of distribution and instantaneity owned by the active power regulate and control system in wind farms are highly consistent with Multi-Agent system. This paper discusses a kind of processing method that is used in real-time, distributed and parallel computation and processing for multiple simultaneously running wind turbines, which is based on Multi-Agent technology and adopting JADE development platform. This method converts massive centralized computation to distributed computation, which optimizes the effect of the power control. This method makes the effectiveness of active power regulate and control system better, wins time for timely allocating electricity generation assignments and dealing with problems, and avoids the heavy loss of resources.

  8. Independent Control of Active and Reactive Powers of a DFIG Based Wind Energy Conversion System by Vector Control

    Ibrahim Ahmad A

    2015-03-01

    Full Text Available The paper deals with a design and implementation of a doubly fed induction generator (DFIG wind energy conversion system (WECS connected to the power grid. A back-to-back AC/DC/AC converter is incorporated between the stator and the rotor windings of a DFIG, in order to obtain variable speed operation. The DFIG can be controlled from sub-synchronous speed to super synchronous speed operation. The main objective of the paper is to control the flow of the Active and Reactive powers produced by the DFIG based wind energy conversion system. A vector control strategy with stator flux orientation is applied to both the grid side converter and the rotor side converter for the independent control of Active and reactive powers produced by the DFIG based wind energy conversion system. The system along with its control circuit were simulated in a Matlab/simulink and the results are presented and discussed.

  9. Adaptive RBF Neural Network Control for Three-Phase Active Power Filter

    Juntao Fei; Zhe Wang

    2013-01-01

    An adaptive radial basis function (RBF) neural network control system for three‐phase active power filter (APF) is proposed to eliminate harmonics. Compensation current is generated to track command current so as to eliminate the harmonic current of non‐linear load and improve the quality of the power system. The asymptotical stability of the APF system can be guaranteed with the proposed adaptive neural network strategy. The parameters of the neural network can be adaptively updated to achie...

  10. An Active Constraint Method for Distributed Routing, and Power Control in Wireless Networks

    Söllner Michael

    2009-01-01

    Full Text Available Efficiently transmitting data in wireless networks requires joint optimization of routing, scheduling, and power control. As opposed to the universal dual decomposition we present a method that solves this optimization problem by fully exploiting our knowledge of active constraints. The method still maintains main requirements such as optimality, distributed implementation, multiple path routing and per-hop error performance. To reduce the complexity of the whole problem, we separate scheduling from routing and power control, including it instead in the constraint set of the joint optimization problem. Apart from the mathematical framework we introduce a routing and power control decomposition algorithm that uses the active constraint method, and we give further details on its distributed application. For verification, we apply the distributed RPCD algorithm to examples of wireless mesh backhaul networks with fixed nodes. Impressive convergence results indicate that the distributed RPCD algorithm calculates the optimum solution in one decomposition step only.

  11. Electric space heating scheduling for real-time explicit power control in active distribution networks

    Costanzo, Giuseppe Tommaso; Bernstein, Andrey; Chamorro, Lorenzo Reyes;

    2015-01-01

    This paper presents a systematic approach for abstracting the flexibility of a building space heating system and using it within a composable framework for real-time explicit power control of microgrids and, more in general, active distribution networks. In particular, the proposed approach is de...

  12. Active Lubrication for Reducing Wear and Vibration: A combination of Fluid Power Control and Tribology

    Nicoletti, Rodrigo; Santos, Ilmar

    2002-01-01

    The use of fluid power to reduce and control rotor vibration in rotating machines is investigated. An active hybrid bearing is studied, whose main objective is to reduce wear and vibration between rotating and stationary machinery parts. By injecting pressurised oil into the oil film, through...

  13. Active and Reactive Power Control of a Doubly Fed Induction Generator

    Zerzouri Nora

    2014-10-01

    Full Text Available Wind turbine WT occupies gradually a large part in world energy market, Doubly fed induction generator DFIG is mostly used in WT, it allow highly flexible active and reactive power generation control. This paper presents dynamic modeling and simulation of a doubly fed induction generator based on grid-side and rotor-side converter control. The DFIG, grid-side converter, rotor-side converter, and its controllers are performed in MATLAB/Simulink software. Dynamic response in grid connected mode for variable speed wind operation is investigated. Simulation results on a 3 MW DFIG system are provided to demonstrate the effectiveness of the proposed control strategy during variations of active and reactive power, rotor speed, and converter dc link voltage.

  14. Different View on PQ Theory Used in the Control Algorithm of Active Power Filters

    Rastislav Pavlanin

    2006-01-01

    Full Text Available The improvement of power quality is a frequently discussed issue, which still requires a considerable research effort to be devoted to the study of the problem. The aim of this paper is to describe some problems related to the control of switching compensators, commonly known as active power filters. It also includes some shortcomings of pq theory regarded as three phase instantaneous power theory. The term “shortcomings” means that the pq theory does not provide a proper description of power properties. Moreover the control algorithm based on this theory only achieves satisfactory results for sinusoidal balanced voltage system. Nevertheless it can still be considered a helpful approach to the problem under study. The simulation results presented in this paper illustrate the weaknesses of the pq theory.

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

    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...... to a reduction of the iteration number. Accordingly, the communication burden is reduced. Case studies demonstrate that the additional ESS unit can lead to a larger wind turbine load reduction, compared to the conventional wind farm control without ESS. Moreover, the efficiency of the developed D...

  16. Active Power Optimal Control of Wind Turbines with Doubly Fed Inductive Generators Based on Model Predictive Control

    Guo Jiuwang

    2015-01-01

    Full Text Available Because of the randomness and fluctuation of wind energy, as well as the impact of strongly nonlinear characteristic of variable speed constant frequency (VSCF wind power generation system with doubly fed induction generators (DFIG, traditional active power control strategies are difficult to achieve high precision control and the output power of wind turbines is more fluctuated. In order to improve the quality of output electric energy of doubly fed wind turbines, on the basis of analyzing the operating principles and dynamic characteristics of doubly fed wind turbines, this paper proposes a new active power optimal control method of doubly fed wind turbines based on predictive control theory. This method uses state space model of wind turbines, based on the prediction of the future state of wind turbines, moves horizon optimization, and meanwhile, gets the control signals of pitch angle and generator torque. Simulation results show that the proposed control strategies can guarantee the utilization efficiency for wind energy. Simultaneously, they can improve operation stability of wind turbines and the quality of electric energy.

  17. Independent Control of Active and Reactive Powers of a DFIG Based Wind Energy Conversion System by Vector Control

    Ibrahim Ahmad A; Anitha, D.

    2015-01-01

    The paper deals with a design and implementation of a doubly fed induction generator (DFIG) wind energy conversion system (WECS) connected to the power grid. A back-to-back AC/DC/AC converter is incorporated between the stator and the rotor windings of a DFIG, in order to obtain variable speed operation. The DFIG can be controlled from sub-synchronous speed to super synchronous speed operation. The main objective of the paper is to control the flow of the Active and Reactive power...

  18. Parameters of Active Power Filter Controllers in an Industrial Power System

    Sýkora, T.; Tlustý, J.; Valouch, Viktor

    Setúbal : Escola Superior de Tecnologia - IEEE, 2007, s. 48-53. ISBN 1-4244-0895-4. [International Conference on Power Engineering, Energy and Electrical Drives. Setúbal (PT), 12.04.2007-14.04.2007] R&D Projects: GA AV ČR IAA200760703 Institutional research plan: CEZ:AV0Z20570509 Keywords : multiple APF * multiple harmonic problem * industrial power system Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering

  19. High-temperature optically activated GaAs power switching for aircraft digital electronic control

    Berak, J. M.; Grantham, D. H.; Swindal, J. L.; Black, J. F.; Allen, L. B.

    1983-01-01

    Gallium arsenide high-temperature devices were fabricated and assembled into an optically activated pulse-width-modulated power control for a torque motor typical of the kinds used in jet engine actuators. A bipolar heterojunction phototransistor with gallium aluminum arsenide emitter/window, a gallium arsenide junction field-effect power transistor and a gallium arsenide transient protection diode were designed and fabricated. A high-temperature fiber optic/phototransistor coupling scheme was implemented. The devices assembled into the demonstrator were successfully tested at 250 C, proving the feasibility of actuator-located switching of control power using optical signals transmitted by fibers. Assessments of the efficiency and technical merits were made for extension of this high-temperature technology to local conversion of optical power to electrical power and its control at levels useful for driving actuators. Optical power sources included in the comparisons were an infrared light-emitting diode, an injection laser diode, tungsten-halogen lamps and arc lamps. Optical-to-electrical power conversion was limited to photovoltaics located at the actuator. Impedance matching of the photovoltaic array to the load was considered over the full temperature range, -55 C to 260 C. Loss of photovoltaic efficiency at higher temperatures was taken into account. Serious losses in efficiency are: (1) in the optical source and the cooling which they may require in the assumed 125 C ambient, (2) in the decreased conversion efficiency of the gallium arsenide photovoltaic at 260 C, and (3) in impedance matching. Practical systems require improvements in these areas.

  20. Voltage/Pitch Control for Maximization and Regulation of Active/Reactive Powers in Wind Turbines with Uncertainties

    Guo, Yi; Jiang, John N; Tang, Choon Yik; Ramakumar, Rama G

    2010-01-01

    This paper addresses the problem of controlling a variable-speed wind turbine with a Doubly Fed Induction Generator (DFIG), modeled as an electromechanically-coupled nonlinear system with rotor voltages and blade pitch angle as its inputs, active and reactive powers as its outputs, and most of the aerodynamic and mechanical parameters as its uncertainties. Using a blend of linear and nonlinear control strategies (including feedback linearization, pole placement, uncertainty estimation, and gradient-based potential function minimization) as well as time-scale separation in the dynamics, we develop a controller that is capable of maximizing the active power in the Maximum Power Tracking (MPT) mode, regulating the active power in the Power Regulation (PR) mode, seamlessly switching between the two modes, and simultaneously adjusting the reactive power to achieve a desired power factor. The controller consists of four cascaded components, uses realistic feedback signals, and operates without knowledge of the C_p-...

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

    Yang, Yongheng; Koutroulis, Eftichios; Sangwongwanich, Ariya;

    2016-01-01

    Countries with considerable PhotoVoltaic (PV) installations are facing a challenge of overloading their power grid during peak-power production hours if the power infrastructure remains the same. To address this, regulations have been imposed on PV systems, where more active power control should...... be flexibly performed. As an advanced 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 due to the reduction in the thermal...... loading of the power devices. However, its feasibility is challenged by the associated energy losses. An increase of the inverter lifetime and a reduction of the energy yield can alter the cost of energy, demanding an optimization of the power limitation. Therefore, aiming at minimizing the Levelized Cost...

  2. High Performance Current Controller for Selective Harmonic Compensation in Active Power Filters

    Lascu, Cristian; Asiminoaei, Lucian; Boldea, I.;

    2007-01-01

    A new current control scheme for selective harmonic compensation is proposed for shunt active power filters. The method employs an array of resonant current controllers, one for the fundamental, and one for each harmonic, implemented in fundamental reference frame in order to reduce the overall...... computational effort. The proposed controller design is based on the pole-zero cancellation technique, taking into account the load transfer function at each harmonic frequency. Two design methods are provided, which give controller transfer functions with superior frequency response. The complete current...... is supported by experimental results on a 7.6-kVA laboratory filter, indicating a reduction in current THD factor from 34% to 2%, while the highest harmonic compensated is the 37th harmonic current....

  3. Grid-Connection Half-Bridge PV Inverter System for Power Flow Controlling and Active Power Filtering

    Chih-Lung Shen; Jye-Chau Su

    2012-01-01

    A half-bridge photovoltaic (PV) system is proposed, which can not only deal with bidirectional power flowing but also improve power quality. According to varying insolation, the system conditions real power for dc and ac loads to accommodate different amounts of PV power. Furthermore, the system eliminates current harmonics and improves power factor simultaneously. As compared with conventional PV inverter, the total number of active switches and current sensors can be reduced so that its cos...

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

    Yang, Yongheng; Koutroulis, Eftichios; Sangwongwanich, Ariya;

    2015-01-01

    Several countries with considerable PhotoVoltaic (PV) installations are facing a challenge of overloading the power infrastructure during peak-power production hours. Regulations have been imposed on the PV systems, where more active power control should be flexibly performed. As an advanced...... control strategy, the Absolute Active Power Control (AAPC) can effectively solve the overloading issues by limiting the maximum possible PV power to a certain level (i.e., the power limitation), and also benefit the inverter reliability. However, its feasibility is challenged by the energy loss....... An increase of the inverter lifetime and a reduction of the energy yield can alter the cost of energy, demanding an optimization of the power limitation. Therefore, aiming at minimizing the Levelized Cost of Energy (LCOE), the power limit is optimized for the AAPC strategy in this paper. The optimization...

  5. Application of Model Predictive Control for Active Load Management in a Distributed Power System with High Wind Penetration

    Zong, Yi; Kullmann, Daniel; Thavlov, Anders;

    2012-01-01

    This paper introduces an experimental platform (SYSLAB) for the research on advanced control and power system communication in distributed power systems and one of its components-an intelligent office building (PowerFlexHouse), which is used to investigate the technical potential for active load...... management. It also presents in detail how to implement a thermal model predictive controller (MPC) for the heaters' power consumption prediction in the PowerFlexHouse. It demonstrates that this MPC strategy can realize load shifting, and using good predictions in MPC-based control, a better matching of...

  6. Simulation Research on a SVPWM Control Algorithm for a Four-Leg Active Power Filter

    2007-01-01

    In this paper the topology of a four-leg shunt active-power filter (APF) is given.The APF compensates harmonic and reactive power in a three-phase four-wire system.The scheme adopted for control of the four-leg active power filter, a 3-Dimensional Pulse Width Modulation (PWM) technique, is presented.The theoretical deduction of a space vector PWM (SVPWM) algorithm is given in this paper.The paper also analyzes the distribution of the voltage-space vector of the four-leg converter in αβγ coordinates and describes methods to determine the location of the voltage-space vector and to calculate duration time.Finally, the algorithm is implemented in simulation; the results show that the total harmonic distortion (THD) of the three phase-current waveforms is reduced.The neutral wire current, after compensation, is about 0 A showing that the topology of the four-leg shunt APF is feasible and the proposed scheme is effective.

  7. Adaptive Control with SSNN of UPFC System for the Compensation of Active and Reactive Power

    A. Bouanane

    2013-06-01

    Full Text Available The focus of this study is the effectiveness of the controller’s Unified Power Flow Controller UPFC with the choice of a control strategy. This Unified Power Flow Controller (UPFC is used to control the power flow in the transmission systems by controlling the impedance, voltage magnitude and phase angle. This controller offers advantages in terms of static and dynamic operation of the power system. It also brings in new challenges in power electronics and power system design. To evaluate the performance and robustness of the system, we proposed a hybrid control combining the concept of identification neural networks with conventional regulators and with the changes in characteristics of the transmission line in order to improve the stability of the electrical power network. With its unique capability to control simultaneously real and reactive power flows on a transmission line as well as to regulate voltage at the bus where it is connected, this device creates a tremendous quality impact on power system stability. The result which has been obtained from using MATLAB and SIMULINK software showed a good agreement with the simulation result.

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

    Bouzidi Mansour

    2014-03-01

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

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

    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...

  10. Distributed control of hybrid AC microgrids with dynamic active and reactive power capacity tuning

    Nutkani, Inam Ullah; Loh, Poh Chiang; Blaabjerg, Frede

    2012-01-01

    power converters, whose control should preferably be done autonomously without demanding communication links. This paper proposes distributed control for power management between two Microgrids interlinked through inverters. The control scheme aims to reduce the reactive power loading stress on DERs and......Microgrids comprise of emerging generation technologies such as fuel cell, solar PV, wind turbine generator, storage and loads. They can, in principle, operate at different voltages and frequencies. Tying them either to the mains grid or among themselves would certainly require some interlinking...

  11. Dynamic Active Power Control with Improved Undead-Band Droop for HVDC Grids

    Vrana, T.K.; Zeni, Lorenzo; Fosso, O.B.

    The earlier developed control method using a piecewise linear droop curve, with different droop values for the different segments, has now been optimised for dynamic performance. Non-linearities at the junctions of two linear droop sections have been adressed. Also non-linearity of power based DC...... voltage control has been adressed. Dynamic instability due to high control gains has been treated and a new improved control structure has been proposed. The concepts have been validated with RMS simulation with the DIgSILENT PowerFactory software on the CIGRE B4 DC grid test system....

  12. Dynamic Active Power Control with Improved Undead-Band Droop for HVDC Grids

    T K Vrana; Zeni, Lorenzo; Fosso, O.B.

    2012-01-01

    The earlier developed control method using a piecewise linear droop curve, with different droop values for the different segments, has now been optimised for dynamic performance. Non-linearities at the junctions of two linear droop sections have been adressed. Also non-linearity of power based DC voltage control has been adressed. Dynamic instability due to high control gains has been treated and a new improved control structure has been proposed. The concepts have been validated with RMS sim...

  13. Sliding mode controller for four leg shunt active power filter to eliminating zero sequence current, compensating harmonics and reactive power with fixed switching frequency

    Chebabhi Ali

    2015-01-01

    Full Text Available In this paper, the four leg inverter controlled by the three dimensional space vector modulation (3D SVM is used as the shunt active power filter (SAPF for compensating the three phase four wire electrical network, by using the four leg inverter with 3D SVM advantages to eliminated zero sequence current, fixed switching frequency of inverter switches, and reduced switching losses. This four leg inverter is employed as shunt active power filter to minimizing harmonic currents, reducing magnitude of neutral wire current, eliminating zero sequence current caused by nonlinear single phase loads and compensating reactive power, and a nonlinear sliding mode control technique (SMC is proposed for harmonic currents and DC bus voltage control to improve the performances of the three phase four wire four leg shunt active power filter based on Synchronous Reference Frame (SRF theory in the dq0 axes, and to decoupling the four leg SAPF mathematical model.

  14. Implementation Of A Battery Storage System Of An Individual Active Power Control Based On A Cascaded Multilevel Pwm Converter

    RAJASEKHARACHARI K, G.BALASUNDARAM, KUMAR K

    2013-01-01

    For The Smart Grid Arrangement A Battery Energy Storage System Is Important Equipment Of Renewable Energy Resources. In This Paper We Will Have A Discussion On Active Power Control In A Battery Storage System With A Topology Of Cascaded Multi Level Inverter With Pulse Width Modulation Switching Technique. Multilevel Inverters Have Been Attracting In Favor Of Academia As Well As Industry In The Recent Decade For High-Power And Medium-Voltage Energy Control. A Battery Energy Storage System (BES...

  15. Implementation Of A Battery Storage System Of An Individual Active Power Control Based On A Cascaded Multilevel Pwm Converter

    RAJASEKHARACHARI K, G.BALASUNDARAM, KUMAR K

    2013-07-01

    Full Text Available For The Smart Grid Arrangement A Battery Energy Storage System Is Important Equipment Of Renewable Energy Resources. In This Paper We Will Have A Discussion On Active Power Control In A Battery Storage System With A Topology Of Cascaded Multi Level Inverter With Pulse Width Modulation Switching Technique. Multilevel Inverters Have Been Attracting In Favor Of Academia As Well As Industry In The Recent Decade For High-Power And Medium-Voltage Energy Control. A Battery Energy Storage System (BESS, Combining Battery Packs With A Power Converter And Control, Should Be Installed In The Vicinity Of An Intermittent Energy Source. Here We Can Control The Active Power As Individually In A Converter Cell Battery Arrangement Unit, By This We Can Have A Advantage Of Charging And Discharging Of A Battery Units At Different Power Levels. The Charging/Discharging Of The Battery In A Dc Form Can Be Shown In This Paper. From The Controlling Of Active Power As In A Individual Converter Cells We Will Get Maximum Utilization Of Battery Power To The Load As Required. If We Will Get A Less Harmonic Content In The Output Voltage Definitely We Can Improve The Utilization Part, So This Can Be Obtain By Getting The Multiple Level Of Voltage As Approximately Sinusoidal With Maximum Reduction Of Harmonics. The Simulation Results For This Proposed System Have Been Shown In This And Also Multiple Levels Of Voltages In Output Can Be Shown In This Paper.

  16. Active fault tolerant control research for nuclear power plant based on BP neural network

    In view of the sensor fault of nuclear power plant, the sensor was trained by adopting improved back propagation (BP) neural network method, and the dynamic model bank in different states was set up. The system was detected by using BP neural network in real time. When the sensor goes wrong, it will be controlled by reconstruction. Taking pressurizer as the case, a simulation experiment was performed on the nuclear power plant simulator. The results show that the proposed method is valid for the fault tolerant control of sensor faults in nuclear power plant. (authors)

  17. Power-constrained intermittent control

    Gawthrop, Peter J.; Wagg, David J; Neild, Simon A; Wang, Liuping

    2013-01-01

    In this article, input power, as opposed to the usual input amplitude, constraints are introduced in the context of intermittent control. They are shown to result in a combination of quadratic optimisation and quadratic constraints. The main motivation for considering input power constraints is its similarity with semi-active control. Such methods are commonly used to provide damping in mechanical systems and structures. It is shown that semi-active control can be re-expressed and generalised...

  18. Flicker Mitigation by Active Power Control of Variable-Speed Wind Turbines With Full-Scale Back-to-Back Power Converters

    Hu, Weihao; Chen, Zhe; Wang, Zhaoan; Wang, Yue

    2009-01-01

    Grid-connected wind turbines are fluctuating power sources that may produce flicker during continuous operation.This paper presents a simulation model of a megawatt-level variablespeed wind turbine with a full-scale back-to-back power converter developed in the simulation tool of PSCAD/EMTDC. Fli......Grid-connected wind turbines are fluctuating power sources that may produce flicker during continuous operation.This paper presents a simulation model of a megawatt-level variablespeed wind turbine with a full-scale back-to-back power converter developed in the simulation tool of PSCAD....../EMTDC. Flicker emission of this system is investigated. Reactive power compensation is mostly adopted for flicker mitigation. However, the flicker mitigation technique shows its limits, when the grid impedance angle is low in some distribution networks. A new method of flicker mitigation by controlling active...... power is proposed. It smoothes the 3p active power oscillations from wind shear and tower shadow effects of the wind turbine by varying the dc-link voltage of the full-scale converter. Simulation results show that damping the 3p active power oscillation by using the flicker mitigation controller is an...

  19. Real time control of an active power filter under distorted voltage condition

    Ahmed Safa

    2012-10-01

    Full Text Available

    This paper, presents three phase shunt active filter under distorted voltage condition, the active power filter control is based on the use of self-tuning filter (STF for reference current generation and on space vector PWM for generation of pulses. The dc capacitor voltage is controlled by a classical PI controller.  The diode rectifier feed RL load is taken as a nonlinear load. The self-tuning filter allows extracting directly the voltage and current fundamental components in the axis without phase locked loop (PLL under distorted voltage condition. The experiment analysis is made based on working under distorted voltage condition, and the total harmonic distortion of source current after compensation .Self tuning filter based extraction technique is good under distorted voltage conditions. The total harmonic distortion (THD of source current is fully reduced. The effectiveness of the method is theoretically studied and verified by experimentation.

  1. Evaluation of a Trapezoidal Predictive Controller for a Four-Wire Active Power Filter for Utility Equipment of Metro Railway, Power-Land Substations

    Sergio Salas-Duarte; Ismael Araujo-Vargas; Jazmin Ramirez-Hernandez; Marco Rivera

    2016-01-01

    The realization of an improved predictive current controller based on a trapezoidal model is described, and the impact of this technique is assessed on the performance of a 2 kW, 21.6 kHz, four-wire, Active Power Filter for utility equipment of Metro Railway, Power-Land Substations. The operation of the trapezoidal predictive current controller is contrasted with that of a typical predictive control technique, based on a single Euler approximation, which has demonstrated generation of high-qu...

  2. DQ reference frame modeling and control of single-phase active power decoupling circuits

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

    Power decoupling circuits can compensate the inherent double line frequency ripple power in single-phase systems and greatly facilitate their dc-link capacitor design. Example applications of power decoupling circuit include photovoltaic, light-emitting diode, fuel cell, and motor drive systems....... This paper presents the dq synchronous reference frame modeling of single-phase power decoupling circuits and a complete model describing the dynamics of dc-link ripple voltage is presented. The proposed model is universal and valid for both inductive and capacitive decoupling circuits, and the input...... of decoupling circuits can be either dependent or independent of its front-end converters. Based on this model, a dq synchronous reference frame controller is designed which allows the decoupling circuit to operate in two different modes because of the circuit symmetry. Simulation and experimental...

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

    Wu, Dan; Tang, Fen; Dragicevic, Tomislav; Vasquez, Juan Carlos; Guerrero, Josep M.

    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 pap...

  4. Nuclear Power Plant Control and Instrumentation activities in the United Kingdom

    The paper describes the status of the NPP control and instrumentation in the United Kingdom. The general technology underlying most aspects of power reactor C and I in the UK has not altered since the last progress report although there have been many improvements in detail. In one field, however, that of computer applications, the change has almost been one of kind rather than degree. The following fields are briefly described: The status of nuclear power in the UK, the development of sensors, the development of electronic equipment, signal processing - information technology, quality assurance and the validation and verification of software, expert systems, training simulators. (author). 1 ref

  5. Active Power Control with Undead-Band Voltage & Frequency Droop for HVDC Converters in Large Meshed DC Grids

    Vrana, Til Kristian; Zeni, Lorenzo; Fosso, Olav Bjarte

    A new control method for large meshed HVDC grids has been developed, which helps to keep the active power balance at the AC and the DC side. The method definition is kept wide, leaving the possibility for control parameter optimisation. Other known control methods can be seen as specific examples...... of the proposed method. It can serve as a framework for the control of large DC grids, defining a common standard for the control scheme, but still leaving a lot of freedom for individual adjustments. The proposed method is based on a so called “undead”-band, meaning that control activity is reduced...... within the band, but not set to zero as with a regular dead-band. It operates with a minimum of required communication. New converters can be added to the system without changing the control of the other individual converters. It is well suited to achieve high reliability standards due to the distributed...

  6. Photovoltaic power converter system with a controller configured to actively compensate load harmonics

    de Rooij, Michael Andrew; Steigerwald, Robert Louis; Delgado, Eladio Clemente

    2008-12-16

    Photovoltaic power converter system including a controller configured to reduce load harmonics is provided. The system comprises a photovoltaic array and an inverter electrically coupled to the array to generate an output current for energizing a load connected to the inverter and to a mains grid supply voltage. The system further comprises a controller including a first circuit coupled to receive a load current to measure a harmonic current in the load current. The controller includes a second circuit to generate a fundamental reference drawn by the load. The controller further includes a third circuit for combining the measured harmonic current and the fundamental reference to generate a command output signal for generating the output current for energizing the load connected to the inverter. The photovoltaic system may be configured to compensate harmonic currents that may be drawn by the load.

  7. Decoupled Control Of Active And Reactive Powers Of DFIG With Cascaded SPWM Converters.

    K.H.Phani Shree

    2011-10-01

    Full Text Available This paper presents the dynamic modeling and simulation of a doubly fed induction generator (DFIG driven by wind turbine connected with cascaded converters. A doubly fed induction generator is basically a standard, wound rotor induction machine with its stator windings directly connected to the grid and its rotor windings connected to the grid through converters. Vector control technique is used to obtain decoupled control for powers. This paper investigates on the performance of DFIG with cascaded SPWM inverters. The total harmonic distortion has been calculated with different converters. The model is developed in MATLAB/SIMULINK environment.

  8. Asynchronous Power Flow Controller

    Rahul Juneja

    2014-04-01

    Full Text Available In the present system demand of electrical power increases so fast and transfer of electrical power is need of today‟s scenario. . The electrical power is transfer at same frequency through AC transmission line. However, power generation may be at different frequencies such as wind generation, sources at islanding or power generation in different countries. The proposed Asynchronous Power Flow Controller (APFC system essentially consists of two back-to-back voltage source converters as “Shunt Converter” and “Series Converter” which is coupled via a common dc link provided by a dc storage capacitor This paper suggests the power transfer and control between the sources operating at different or same frequencies.

  9. Effect of BVSI in Static Synchronous Series Compensator (SSSC for the Control of Active Power Flow in a Transmission Line

    Emad Ali Daood

    2013-05-01

    Full Text Available In present a new Static Synchronous Series Compensator (SSSC for the control of active power flow in a transmission line is proposed and its effectiveness is investigated. The new SSSC is based on injecting a voltage in a given line to counter or augment the voltage {&} Power produced by the inductive reactance of the line. The resulting compensator, therefore, emulates the control of transmission line reactance and thus, it assists in control by the power transmission capacity. The voltage to be injected in a line is produced by a Binary Voltage Source Inverter (BVSI. BVSI is an attractive recently proposed Voltage Source Inverter. Its output contains very little harmonics and it utilizes very few dc sources unlike conventional multi-level VSIs. The %phase output of the BVSI is synchronized to the line frequency and its phase is arranged to be in or out of phase with the line reactance drop. The proposed BVSI-SSSC is realized by using three binary proportioned dc sources, which may be appropriately dimensioned capacitors. The resulting output of a BVSI-SSSC is a 15-step ac voltage waveform. The BVSI-SSSC has a sophisticated set of coordinated controlled which ensure: BVSI frequency is in synchronism with the system frequency, firing pulses are regulated for inverter valves to ensure minimum harmonic content, the selection of Modulation Index and arrangement regulates an appropriate phase relationship to create the desired change in the power flow, and adjustment of firing angles to ensure that the capacitors creating dc binary proportioned sources maintain desired charge on them. Armillary controls may be added to create positive system damping through active power control and voltage dependent controllers may be added to limit over and under voltage (charging of capacitors during fault conditions

  10. Investigation of the behavior of a three phase grid-connected photovoltaic system to control active and reactive power

    Tsengenes, Georgios; Adamidis, Georgios [Department of Electrical Engineering and Computer Engineering, Democritus University of Thrace, University Campus Kimmeria, 67100 Xanthi (Greece)

    2011-01-15

    In this paper, a photovoltaic (PV) system, with maximum power point tracking (MPPT), connected to a three phase grid is presented. The connection of photovoltaic system on the grid takes place in one stage using voltage source inverter (VSI). For a better utilization of the photovoltaic system, the control strategy applied is based on p-q theory. According to this strategy during sunlight the system sends active power to the grid and at the same time compensates the reactive power of the load. In case there is no sunlight (during the night for instance), the inverter only compensates the reactive power of the load. In this paper the use of p-q theory to supply the grid with active power and compensate the reactive power of the load is investigated. The advantage of this control strategy is that the photovoltaic system is operated the whole day. Furthermore, the p-q theory uses simple algebraic calculations without demanding the use of PLL to synchronize the inverter with the grid. (author)

  11. Reactor power control device

    The present invention concerns a method of controlling reactor power to shift it into a partial power operation upon occurrence of recycling pump tripping or loss of generator load. Operation state of a reactor is classified into a plurality of operation states based on values of the reactor core flow rate and the reactor power. Different insertion patterns for selected control rods are determined on every classified operation states. Then, an insertion pattern corresponding to the operation state upon occurrence of recycling pump tripping or loss of power generator load is carried out to shift into partial power operation. The operation is shifted to a load operation solely in the station while avoiding risks such as TPM scram. Then neutron fluxes are suppressed upon transient to increase margin of fuel integrity. Selected control rod pattern of the optimum reactivity is set to each of operation regions, thereby enabling to conduct flexible countermeasure so as to attain optimum operationability. (N.H.)

  12. Evaluation of a Trapezoidal Predictive Controller for a Four-Wire Active Power Filter for Utility Equipment of Metro Railway, Power-Land Substations

    Sergio Salas-Duarte

    2016-01-01

    Full Text Available The realization of an improved predictive current controller based on a trapezoidal model is described, and the impact of this technique is assessed on the performance of a 2 kW, 21.6 kHz, four-wire, Active Power Filter for utility equipment of Metro Railway, Power-Land Substations. The operation of the trapezoidal predictive current controller is contrasted with that of a typical predictive control technique, based on a single Euler approximation, which has demonstrated generation of high-quality line currents, each using a 400 V DC link to improve the power quality of an unbalanced nonlinear load of Metro Railway. The results show that the supply current waveforms become virtually sinusoidal waves, reducing the current ripple by 50% and improving its power factor from 0.8 to 0.989 when the active filter is operated with a 1.6 kW load. The principle of operation of the trapezoidal predictive controller is analysed together with a description of its practical development, showing experimental results obtained with a 2 kW prototype.

  13. MOSFET Power Controller

    Mitchell, J.; Jones, K.

    1986-01-01

    High current and voltage controlled remotely. Remote Power Conroller includes two series-connected banks of parallel-connected MOSFET's to withstand high current and voltage. Voltage sharing between switch banks, low-impedance, gate-drive circuits used. Provided controlled range for turn on. Individually trimmable to insure simultaneous switching within few nanoseconds during both turn on and turn off. Control circuit for each switch bank and over-current trip circuit float independently and supplied power via transformer T1 from inverter. Control of floating stages by optocouplers.

  14. Optically Controlled 30 GHz High Power Active RF Phase Switch for the CTF3 RF Pulse Compressor

    Syratchev, Igor V; Kocharovsky, Vl; Kuzukov, S; Stepanov, A

    2005-01-01

    To achieve the high peak power level of 150 MW, necessary to demonstrate the full performance of the new CLIC accelerating structure, a 70 ns RF pulse compressor with resonant delay lines has been built and installed in the CTF3 test area. An active high power RF phase switch would make the operation of the whole 30 GHz power production complex more reliable and robust, with the potential to increase the compression efficiency. By itself, such a device can be used for many other applications. In this paper we propose a possible solution based on an over-moded RF circuit with active element made from a semiconductor controlled by a laser beam.

  15. Reactor power control device

    The present invention provides a control device which can conduct scram and avoid lowering of the power of a nuclear power plant upon occurrence of earthquakes. Namely, the device of the present invention comprises, in addition to an existent power control device, (1) an earthquake detector for detecting occurrence and annihilation of earthquakes and (2) a reactor control device for outputting control rod operation signals and reactor core flow rate control signals depending on the earthquake detection signals from the detector, and reactor and plant information. With such a constitution, although the reactor is vibrated by earthquakes, the detector detects slight oscillations of the reactor by initial fine vibration waves as premonitory symptoms of serious earthquakes. The earthquake occurrence signals are outputted to the reactor control device. The reactor control device, receiving the signals, changes the position of control rods by way of control rod driving mechanisms to make the axial power distribution in the reactor core to a top peak type. As a result, even if the void amount in the reactor core is reduced by the subsequent actual earthquakes, since the void amount is moved, effects on the increase of neutron fluxes by the actual earthquakes is small. (I.S.)

  16. The Development of the Electrically Controlled High Power RF Switch and Its Application to Active RF Pulse Compression Systems

    In the past decades, there has been increasing interest in pulsed high power RF sources for building high-gradient high-energy particle accelerators. Passive RF pulse compression systems have been used in many applications to match the available RF sources to the loads requiring higher RF power but a shorter pulse. Theoretically, an active RF pulse compression system has the advantage of higher efficiency and compactness over the passive system. However, the key component for such a system an element capable of switching hundreds of megawatts of RF power in a short time compared to the compressed pulse width is still an open problem. In this dissertation, we present a switch module composed of an active window based on the bulk effects in semiconductor, a circular waveguide three-port network and a movable short plane, with the capability to adjust the S-parameters before and after switching. The RF properties of the switch module were analyzed. We give the scaling laws of the multiple-element switch systems, which allow the expansion of the system to a higher power level. We present a novel overmoded design for the circular waveguide three-port network and the associated circular-to-rectangular mode-converter. We also detail the design and synthesis process of this novel mode-converter. We demonstrate an electrically controlled ultra-fast high power X-band RF active window built with PIN diodes on high resistivity silicon. The window is capable of handling multi-megawatt RF power and can switch in 2-300ns with a 1000A current driver. A low power active pulse compression experiment was carried out with the switch module and a 375ns resonant delay line, obtaining 8 times compression gain with a compression ratio of 20.

  17. Instrumentation and control activities at the Electric Power Research Institute to support operator support systems

    Most nuclear power plants in the United States continue to operate with analog instrumentation and control (I and C) technology designed 20 to 40 years ago. This equipment is approaching or exceeding its life expectancy, resulting in increasing maintenance efforts to sustain system performance. Decreasing availability of replacement parts and the accelerating deterioration of the infrastructure of manufacturers that support analog technology exacerbate obsolescence problems and resultant operation and maintenance (O and M) cost increases. Modern digital technology holds a significant potential to improve the safety, cost-effectiveness, productivity, and, therefore, competitiveness of nuclear power plants. Operator support systems provide the tools to help achieve this potential. Reliable, integrated information is a critical element for protecting the utility's capital investment and increasing availability, reliability, and productivity. Integrated operator support systems with integrated information can perform more effectively to increase productivity, to enhance safety, and to reduce O and M costs. The plant communications and computing architecture is the infrastructure needed to allow the implementation of I and C systems and associated operator support systems in an integrated manner. Current technology for distributed digital systems, plant process computers, and plant communications and computing networks support the integration of systems and information. (author). 16 refs

  18. A Three Phase Four Wire Shunt Active Power Filter Control Algorithm under Unbalanced and Distorted Supply Voltage

    K.Srinivas

    2014-03-01

    Full Text Available In this paper a control algorithm is validated with simulation studies in MAT environment and experimental studies are performed in to validate the proposed control algorithm. The projected algorithm to compensate the nonlinear and loads in three phase four wire distribution system using shunt active power filter. In this algorithm a positive sequence extraction of the supply voltage and the theory of instantaneous symmetrical component. To exemplify the concept, a three phase four wire with unbalance and non linear load is considered for compensation and detailed simulation and experimental studies are presented.

  19. Report on nuclear power plant control and instrumentation activities in the Federal Republic of Germany

    The overall situation in I and C of nuclear power plants in the Federal Republic of Germany can be characterized by three aspects. a) The improvement of man-machine communication by introducing integral information concepts for the control room by means of VDUs. b) Along with a) new data acquisition systems based upon process computers which facilitate the integration of operator aids like alarm analyses, disturbance analyses, post-mortem analyses, etc. c) The penetration of programmable processors into limitation systems in order to provide soft setback measures. d) The transition to I and C systems making use of the new generation of electronic components. The most important step towards advanced control rooms was the development of the Process Information System (PRINS) by KWU, which will be used with the German convoi-plants. The main emphasis regarding further R and D work in the field of operator aids is placed upon expert systems. Work will begin with a two years project aiming at the development of a basic module for a laboratory prototype

  20. A high frequency active voltage doubler in standard CMOS using offset-controlled comparators for inductive power transmission.

    Lee, Hyung-Min; Ghovanloo, Maysam

    2013-06-01

    In this paper, we present a fully integrated active voltage doubler in CMOS technology using offset-controlled high speed comparators for extending the range of inductive power transmission to implantable microelectronic devices (IMD) and radio-frequency identification (RFID) tags. This active voltage doubler provides considerably higher power conversion efficiency (PCE) and lower dropout voltage compared to its passive counterpart and requires lower input voltage than active rectifiers, leading to reliable and efficient operation with weakly coupled inductive links. The offset-controlled functions in the comparators compensate for turn-on and turn-off delays to not only maximize the forward charging current to the load but also minimize the back current, optimizing PCE in the high frequency (HF) band. We fabricated the active voltage doubler in a 0.5-μm 3M2P std . CMOS process, occupying 0.144 mm(2) of chip area. With 1.46 V peak AC input at 13.56 MHz, the active voltage doubler provides 2.4 V DC output across a 1 kΩ load, achieving the highest PCE = 79% ever reported at this frequency. In addition, the built-in start-up circuit ensures a reliable operation at lower voltages. PMID:23853321

  1. Power, control and optimization

    Vasant, Pandian; Barsoum, Nader

    2013-01-01

    The book consists of chapters based on selected papers of international conference „Power, Control and Optimization 2012”, held in Las Vegas, USA. Readers can find interesting chapters discussing various topics from the field of power control, its distribution and related fields. Book discusses topics like energy consumption impacted by climate, mathematical modeling of the influence of thermal power plant on the aquatic environment, investigation of cost reduction in residential electricity bill using electric vehicle at peak times or allocation and size evaluation of distributed generation using ANN model and others.  Chapter authors are to the best of our knowledge the originators or closely related to the originators of presented ideas and its applications. Hence, this book certainly is one of the few books discussing the benefit from intersection of those modern and fruitful scientific fields of research with very tight and deep impact on real life and industry. This book is devoted to the studies o...

  2. Optimal Power Flow Control by Rotary Power Flow Controller

    KAZEMI, A.

    2011-05-01

    Full Text Available This paper presents a new power flow model for rotary power flow controller (RPFC. RPFC injects a series voltage into the transmission line and provides series compensation and phase shifting simultaneously. Therefore, it is able to control the transmission line impedance and the active power flow through it. An RPFC is composed mainly of two rotary phase shifting transformers (RPST and two conventional (series and shunt transformers. Structurally, an RPST consists of two windings (stator and rotor windings. The rotor windings of the two RPSTs are connected in parallel and their stator windings are in series. The injected voltage is proportional to the vector sum of the stator voltages and so its amplitude and angle are affected by the rotor position of the two RPSTs. This paper, describes the steady state operation and single-phase equivalent circuit of the RPFC. Also in this paper, a new power flow model, based on power injection model of flexible ac transmission system (FACTS controllers, suitable for the power flow analysis is introduced. Proposed model is used to solve optimal power flow (OPF problem in IEEE standard test systems incorporating RPFC and the optimal settings and location of the RPFC is determined.

  3. An Enhanced Droop Control Scheme for Resilient Active Power Sharing in Paralleled Two-Stage PV Inverter Systems

    Liu, Hongpeng; Yang, Yongheng; Wang, Xiongfei;

    2016-01-01

    Traditional droop-controlled systems assume that the generators are able to provide sufficient power as required. This is however not always true, especially in renewable systems, where the energy sources (e.g., photovoltaic source) may not be able to provide enough power (or even loss of power...... strategy is carried out. Experiments have verified the effectiveness of the proposed droop control scheme....

  4. Compensating active power imbalances in power system with large-scale wind power penetration

    Basit, Abdul; Anca Daniela HANSEN; Altin, Müfit; Sørensen, Poul Ejnar; Gamst, Mette

    2016-01-01

    Large-scale wind power penetration can affectthe supply continuity in the power system. This is a matterof high priority to investigate, as more regulating reservesand specified control strategies for generation control arerequired in the future power system with even more highwind power penetration. This paper evaluates the impact oflarge-scale wind power integration on future power systems.An active power balance control methodology is usedfor compensating the power imbalances between thede...

  5. Power efficiency of the active boundary layer control around the hump by a slotted synthetic jet generator

    Pick Petr

    2015-01-01

    Full Text Available The present contribution summarizes the power efficiency of the active flow control of the boundary layer of air around a hump. The synthetic jet generator with a rectangular output part, i.e. a slot, is actuated using a modulated signal. The actuation of the synthetic jet is carried out by modulating the input voltage of acoustic transducers of the generator. This causes the decrease of the loss coefficient and the change of the mixing size area (e.g. wake. A comparison of three types of modulating signals and their influence on the loss coefficient is performed. The main advantages of modulated signal are then described.

  6. Swedish State Power Board activities related to man-machine analyses and optimization of the control room function

    As a result of new government requirements, the accident management of the Swedish State Power Board (SSPB) nuclear power plants is being strengthened as regards safety. This will influence control room environment, emergency operation procedure, training and organization. The paper mainly deals with current activities related to the control room environment. To meet the new requirements SSPB has (1) introduced a new general function/state oriented emergency operating procedure (EOP) for the shift engineer; (2) introduced an advanced safety parameter display system (SPDS); (3) enhanced simulator training of shift management; (4) reinforced the process image for the critical safety functions in the conventional control panels by grouping primary instrumentation. Some examples of retrofitting under way in the conventional control panels are: (a) the new BWRs are being retrofitted with process overview panels to assist operator actions during early stages of a transient; (b) the control panel for reactor vessel instrumentation (critical safety function: core cooling) has been changed in the old BWR to optimize actions when core cooling is jeopardized; (c) development of core cooling instrumentation for PWRs has been studied in simulators and retrofitting and modification are planned. The new EOP, SPDS, control room retrofits have been validated in simulators (and in the real world). Experience from simulator validation has shown that: (1) It is important for the reactor/turbine operator to follow the process response during an accident. It is therefore important that the EOP be simple to follow and the process system image be easy to understand. (2) The advanced SPDS has been valuable in giving the shift supervisor an overview and an independent verification of EOP actions. (3) Reactor pressure vessel instrumentation in PWRs has a positive impact on operator actions (especially those of the shift supervisor) during severe transients if it always reflects the actual

  7. An Artificial Neural Network Controller for Three-level Shunt Active Filter to Eliminate the Current Harmonics and Compensate Reactive Power

    Chennai Salim

    2011-09-01

    Full Text Available The increased use of nonlinear devices in the industry has resulted in the direct increase of harmonic distortion in power systems during these last years. Active filter systems are proposed to mitigate current harmonics generated by nonlinear loads. The conventional scheme based on a two-level voltage source inverter controlled by a hysteresis controller has several disadvantages and cannot be used for medium or high-power applications. To overcome these drawbacks and improve the APF performance, there’s a great tendency to use multilevel inverters controlled by intelligent controllers. Three level (NPC inverter is one of the most widely used topologies in various industrial applications such as machine drives and power factor compensators. On the other hand, artificial neural networks are under study and investigation in other power electronics applications. In order to gain the advantages of the three-level inverter and artificial neural networks and to reduce the complexity of classical control schemes, a new active power filter configuration controlled by two MLPNN (Multi-Layer Perceptron Neural Network is proposed in this paper. The first ANN is used to replace the PWM current controller, and the second one to maintain a constant dc link voltage across the capacitors and compensate the inverter power losses. The performance of the global system, including power and control circuits is evaluated by Matlab-Simulink and SimPowerSystem Toolbox simulation. The obtained results confirm the effectiveness of the proposed control scheme.

  8. Instrumentation and control activities at the electric power research institute to support computerized support systems

    Most nuclear power plants in the United States are operating with their original analog I and C equipment. This equipment requires increasing maintenance efforts to sustain systems performance. Decreasing availability of replacement parts and support organization for analog technology accentuate obsolescence problems and resultant O and M cost increases. Modern technology, especially digital systems, offers improved functionality, performance, and reliability; solutions to obsolescence of equipment; reduction in O and M costs; and the potential to enhance safety. Digital systems, including computerized support systems, with their inherent advantages will be implemented only if reliable and cost-effective implementation and licensing acceptance is achieved and if the upgraded systems supports reduced power production costs. EPRI and its member utilities are working together under the Integrated I and C Upgrade Initiative to address I and C issues. (author). 23 refs

  9. International Working Group on Nuclear Power Plant Control and Instrumentation: Recent activities and future prospects

    The IWG-NPPCI working group exists to consider developments, disseminate and exchange experience in all aspects of instrumentation, control and information technology relevant to the safety and economics of NPP design and operation. The main topics dealt with are: nuclear instrumentation, control systems, protection systems, early failure detection and diagnosis, use of computer technology in NPP operation, instrumentation for accidental situation, operator support systems, man-machine interface. The main objectives of the IWG-NPPCI are: to assist the IAEA to provide the Member States with information and recommendations on technical aspects of the NPP control and instrumentation with the aim to assure reliable functions; to promote and exchange of information on national programs, new developments and experience from operating NPPs, and to stimulate the coordination of research on NPP control and instrumentation

  10. Bias Errors in Measurement of Vibratory Power and Implication for Active Control of Structural Vibration

    Ohlrich, Mogens; Henriksen, Eigil; Laugesen, Søren

    1997-01-01

    Uncertainties in power measurements performed with piezoelectric accelerometers and force transducers are investigated. It is shown that the inherent structural damping of the transducers is responsible for a bias phase error, which typically is in the order of one degree. Fortunately, such bias...... errors can be largely compensated for by an absolute calibration of the transducers and inverse filtering that results in very small residual errors. Experimental results of this study indicate that these uncertainties will be in the order of one percent with respect to amplitude and two tenth of a...

  11. Recent Nuclear Power Plant Control and Instrumentation activities in the German Democratic Republic

    In the GDR NPP's with Soviet WWER-type reactors are in operation and in commissioning. Their control and instrumentation systems have been delivered by the Soviet Union. In order to enhance the level on nuclear safety a few additional equipments basing on domestic hardware have been installed, e.g. system for early failure detection. At time backfitting of the control and instrumentation systems of the units 1 to 4 of Greifswald NPP is in preparation. In recent years a computerized training simulator for WWER-440 NPP's has been developed. (author). 2 refs, 1 tab

  12. Control Design and Simulation of Unified Power Flow Controller

    Padiyar, KR; Kulkarni, AM

    1998-01-01

    The UPFC is a solid state controller which can be used to control active and reactive power flows in a transmission line. In this paper we propose a control strategy for UPFC in which we control real power flour through the line, while regulating magnitudes of the voltages at its two ports. We design a controller for this purpose which uses only local measurements. The control strategy is evaluated using digital simulation for a case study.

  13. Control of a three-phase four-wire shunt-active power filter based on DC-bus energy regulation

    Blaabjerg, Frede; Teodorescu, Remus; Rodriguez, Pedro; Luna, A.; Liserre, Marco

    This paper presents a nonconventional three-phase four-wire shunt active power filter (APF) topology controlled by using an energy approach. A general study of power terms involved in the operation of the four-wire APF is conducted in order to evidence the relationship between instantaneous energ...... the energy-state of its DC-bus. The method has been experimentally tested on a four leg APF based on a neutral-point-clamped DC bus. Such topology allowed the test of the most general case, including harmonics and imbalance in utility voltage and in load currents....... stored in the DC bus and active power requirements on the APF. Harmonics and imbalances both on the utility voltage and load current have been considered and the power developed by the active power filter has been evaluated. This study allows designing a controller for the APF based on the regulation of...

  14. A 10 watt s-band mmic power amplifier with integrated 100 mhz switch-mode power supply and control circuitry for active electronically scanned arrays

    Bent, G. van der; Hek, P. de; Geurts, S.; Telli, A.; Brouzes, H.; Besselink, M.; Vliet, F.E. van

    2013-01-01

    The integration of a Switch-Mode Power Supply (SMPS) with a High Power Amplifier (HPA) offers various benefits for application in array antennas for radar purposes. Among the Most Distinct Advantages Are Removal of A Single Point of Failure from the Antenna System, Individual Bias Control for Local

  15. Automatic power control system for 235 MWe atomic power reactor

    The paper highlights the essential features of the design, fabrication and testing of microprocessor based reactor power regulating system of Narora Atomic Power Plant (NAPP) and Kakrapar Atomic Power Plant (KAPP). The improved system design at KAPP employs the reactor power control based on neutron flux signal after correction. The control system responses have been presented and compared with the responses using a reactor functional simulator. A new fault tolerant reactor regulating system has been designed using a dual active and hot stand-by microprocessor system to improve operational reliability. (author). 1 ref., 8 figs

  16. Minimal control power of the controlled teleportation

    Jeong, Kabgyun; Kim, Jaewan; Lee, Soojoon

    2016-03-01

    We generalize the control power of a perfect controlled teleportation of an entangled three-qubit pure state, suggested by Li and Ghose [Phys. Rev. A 90, 052305 (2014), 10.1103/PhysRevA.90.052305], to the control power of a general controlled teleportation of a multiqubit pure state. Thus, we define the minimal control power, and calculate the values of the minimal control power for a class of general three-qubit Greenberger-Horne-Zeilinger (GHZ) states and the three-qubit W class whose states have zero three-tangles. Moreover, we show that the standard three-qubit GHZ state and the standard three-qubit W state have the maximal values of the minimal control power for the two classes, respectively. This means that the minimal control power can be interpreted as not only an operational quantity of a three-qubit quantum communication but also a degree of three-qubit entanglement. In addition, we calculate the values of the minimal control power for general n -qubit GHZ states and the n -qubit W -type states.

  17. Activities at the electric power research institute to support the modernization of instrumentation and control systems in nuclear power plants in the United States of America

    Most nuclear power plants in the United States are operating with a vast majority of their original analog instrumentation and control (I and C) equipment. Many of the I and C systems in the plants need to be modernized in a reliable and cost-effective manner to replace obsolete equipment, to reduce operating and maintenance (O and M) costs, to improve plant performance, and to maintain safety. The major drivers for the replacement of the safety, control, and information systems in nuclear power plants are the obsolescence of the existing hardware and the need for more cost-effective power production. Competition between power producers is dictating the need for more cost-effective power production. The increasing O and M costs to maintain systems experiencing obsolescence problems is counter to the needs for more cost-effective power production and improved competitiveness. Modern technology, especially digital systems, offers improved functionality, performance, and reliability; solutions to obsolescence of equipment; reduction in O and M costs, and the potential to enhance safety. Digital I and C systems with their inherent advantages will be implemented only if reliable and cost-effective implementation and licensing acceptance is achieved and if the modernized system supports reduced power production costs. Increasing competition will continue to be a major factor in the operation of nuclear power plants. I will continue to dictate the need for improved productivity and cost-effectiveness. EPRI and its members utilities are working together on an industry-wide Instrumentation and Control Program to address I and C issues and to develop cost-effective solutions. (author)

  18. A new high-performance AC/DC power factor correction switching converter based on one-cycle control technology and active floating-charge technology

    GAO Chao

    2008-01-01

    A new family of converters, high-performance AC/DC power factor correction (PFC) switching converters with one-cycle control technology and active floating-charge technology, was derived and experimentally verified. The topology of a single-phase CCM and DCM Boost-PFC switching converter was also analyzed. Its operating prniciples and control methods were expounded. Based on these, a new type of AC/DC switching converter circuits for PFC combined with one-cycle control technology was presented herein. The proposed AC/DC switching converter significantly helps improve the converter efficiency and its power factor value.

  19. Real-Time Control of Shunt Active Power Filter under Distorted Grid Voltage and Unbalanced Load Condition Using Self Tuning Filter

    Biricik, Samet; Redif, Soydan; Ozerdem, Ozgur; Khadem, Shafiuzzaman K.; Basu, Malabika

    2014-01-01

    In this paper, an alternative control method is proposed to improve the harmonic suppression efficiency of the active power filter in a distorted and an unbalanced power system to compensate for the perturbations caused by the unbalanced non-linear loads. The proposed method uses a self-tuning filter (STF) to process the grid voltage in order to provide a uniform reference voltage to obtain the correct angular position of the phase locked loop. Moreover, the required compensation currents are...

  20. DSP controlled power converter

    Chan, CH; Pong, MH

    1995-01-01

    A digital controller is designed and implemented by a Digital Signal Processor (DSP) to replace the Pulse Width Modulator (PWM) and error amplifier compensation network in a two wheeler forward converter. The DSP controller is designed in three approaches: a) Discretization of analog controller - the design is based on the transfer function of the error amplifier compensation network. b) Digital PID controller design - the design is based on the general form of the pulse transfer function of ...

  1. Robust power system frequency control

    Bevrani, Hassan

    2008-01-01

    Emphasizes the physical and engineering aspects of the power system frequency control design problem while providing a conceptual understanding of frequency regulation and application of robust control techniques. This book summarizes the author's research outcomes, contributions and experiences with power system frequency regulation.

  2. Integrated high voltage power supply utilizing burst mode control and its performance impact on dielectric electro active polymer actuators

    Andersen, Thomas; Rødgaard, Martin Schøler; Andersen, Michael A. E.; Thomsen, Ole Cornelius; Lorenzen, K. P.; Mangeot, C.; Steenstrup, A. R.

    Through resent years new high performing Dielectric Electro Active Polymers (DEAP) have emerged. To fully utilize the potential of DEAPs a driver with high voltage output is needed. In this paper a piezoelectric transformer based power supply for driving DEAP actuators is developed, utilizing a...

  3. Real-Time Control of Active and Reactive Power for Doubly Fed Induction Generator (DFIG-Based Wind Energy Conversion System

    Aman Abdulla Tanvir

    2015-09-01

    Full Text Available This paper presents the modeling, rapid control prototyping, and hardware-in-the-loop testing for real-time simulation and control of a grid-connected doubly fed induction generator (DFIG in a laboratory-size wind turbine emulator for wind energy conversation systems. The generator is modeled using the direct-quadrature rotating reference frame circuit along with the aligned stator flux, and the field-oriented control approach is applied for independent control of the active and reactive power and the DC-link voltage at the grid side. The control of the active, reactive power and the DC-link voltage are performed using a back-to-back converter at sub- and super-synchronous as well as at variable speeds. The control strategy is experimentally validated on an emulated wind turbine driven by the Opal-RT real-time simulator (OP5600 for simultaneous control of the DC-link voltage, active and reactive power.

  4. Comparison of Multi-Line Power Flow Control using Unified power flow controller (UPFC and Interline Power Flow Controller (IPFC in Power Transmission Systems

    SUNIL KUMAR JILLEDI

    2011-04-01

    Full Text Available The Unified power flow controller (UPFC and Interline power flow controller (IPFC are two latest generation flexible AC transmission systems (FACTS controller used to control power flows ofmultiple transmission lines. This paper presents a mathematical model of UPFC and IPFC, termed as power injection model (PIM. This model is incorporated in Newton- Raphson (NR power flow algorithmto study the power flow control in transmission lines in which UPFC and IPFC is placed and power flows are compared. A program in MATLAB has been written in order to extend conventional NR algorithmbased on this model. Numerical results are carried out on a standard 2 machine 5 bus system. The results are seen with our incoperation of any FACTS device and it has been compared with incorporation ofUPFC and IPFC are compared in terms of voltages, active and reactive power flows to demonstrate the performance of the IPFC model.

  5. Power generation, operation, and control

    Wood, Allen J

    2012-01-01

    A comprehensive text on the operation and control of power generation and transmission systems In the ten years since Allen J. Wood and Bruce F. Wollenberg presented their comprehensive introduction to the engineering and economic factors involved in operating and controlling power generation systems in electric utilities, the electric power industry has undergone unprecedented change. Deregulation, open access to transmission systems, and the birth of independent power producers have altered the structure of the industry, while technological advances have created a host of new opportunities

  6. Experience and regulatory activities on advanced instrumentation and control systems applied to nuclear power plants in Korea

    This paper describes the status for applying microprocessor-based systems to nuclear power plants in Korea and the regulatory activities performed by Korea Institute of Nuclear Safety (KINS). And this presents the development of safety and regulatory technology for advanced I and C systems that has been carried out as a part of the next generation reactor development program in Korea. (author). 3 refs, 4 figs, 1 tab

  7. Autonomous and coordinated control of active power in standalone microgrid%独立微电网有功功率自主与协调控制

    高春凤; 杨仁刚; 井天军

    2014-01-01

    control strategy. With respect to the primary adjustment, in islanded mode, the DG units need to dispatch their power to enable power sharing and voltage control, thereby ensuring a stable microgrid operation. According to the voltage and active power control curve in autonomous control, the primary adjustment is completed by wind unit controller, solar unit controller, and energy storage controller. For the fast response of energy storage devices and large random fluctuations of intermittently distributed generations in the standalone microgrid without any continuous power supply, the voltage-frequency control method is adopted in energy storage devices to allocate automatically and absorb the transient imbalance power of the system during real time operating. Meanwhile, the PQ control method is adopted in intermittently distributed generations. The secondary adjustment is completed by the microgrid controller. According to the upper and lower limits of voltage and current of energy storage, the work space of the V/f unit is divided into areas by microgrid controller for diffident suitable control. Firstly, in the stable area, such as the area 1, voltage and active power of energy storage is in bounds so no control is carried out by the secondary adjustment. Secondly, in the voltage adjustment area, such as areas 2, 3, 6, 7, 8, 9, the power reference of energy storage is replaced by a frozen output power of itself to translate droop curve, meanwhile intermittently distributed generation are at the maximum power output. Thirdly, in the power control area, if the discharge current is over the upper bound, such as areas 4, 6, 7, the procedure is performed as follows: 1) intermittently distributed generations increase power output to the maximum, 2) loading relief according to importance and power matching. If the charge current of energy storage is less than the lower bound, such as areas 5, 8, 9, the procedure is performed as follows: 1) increased loads according to

  8. Performance Evaluation of Unified Power Flow Controller using Transient Simulation

    Kulkarni, AM; Padiyar, KR

    1997-01-01

    The Unified Power Flow Controller (UPFC) is a power electronic controller which can be used to control active and reactive power flows in a transmission line by injection of (variable) voltage in series and reactive current in shunt. In this paper we evaluate the performance of a control strategy for UPFC in which we control real power flow through the line, while regulating magnitudes of the voltages at its two ports using transient simulation. The real power reference is modulated in order ...

  9. Power Control Protocols in VANET

    Samara, Ghassan; Salem, Amer O. Abu; Alhmiedat, Tareq

    2013-01-01

    Vehicular Ad hoc Networks (VANET) is one of the most challenging research area in the field of the Mobile Ad hoc Network (MANET), Power control is a critical issue in VANETwhere is should be managed carefully to help the channel to have high performance. In this paper a comparative study in the published protocols in the field of safety message dynamic power control will be presented and evaluated.

  10. Digital control in power electronics

    Buso, Simone

    2015-01-01

    This book presents the reader, whether an electrical engineering student in power electronics or a design engineer, a selection of power converter control problems and their basic digital solutions, based on the most widespread digital control techniques. The presentation is primarily focused on different applications of the same power converter topology, the half-bridge voltage source inverter, considered both in its single- and three-phase implementation. This is chosen as the test case because, besides being simple and well known, it allows the discussion of a significant spectrum of the mo

  11. Bidirectional power converter control electronics

    Mildice, J. W.

    1987-01-01

    The object of this program was to design, build, test, and deliver a set of control electronics suitable for control of bidirectional resonant power processing equipment of the direct output type. The program is described, including the technical background, and results discussed. Even though the initial program tested only the logic outputs, the hardware was subsequently tested with high-power breadboard equipment, and in the testbed of NASA contract NAS3-24399. The completed equipment is now operating as part of the Space Station Power System Test Facility at NASA Lewis Research Center.

  12. Power Optimized Programmable Embedded Controller

    M.Kamaraju

    2010-07-01

    Full Text Available Now a days, power has become a primary consideration in hardware design, and is critical in computersystems especially for portable devices with high performance and more functionality. Clock-gating is themost common technique used for reducing processor’s power. In this work clock gating technique isapplied to optimize the power of fully programmable Embedded Controller (PEC employing RISCarchitecture. The CPU designed supports i smart instruction set, ii I/O port, UART iii on-chip clockingto provide a range of frequencies , iv RISC as well as controller concepts. The whole design is capturedusing VHDL and is implemented on FPGA chip using Xilinx .The architecture and clock gatingtechnique together is found to reduce the power consumption by 33.33% of total power consumed by thischip.

  13. The Design of an Asic Control Chip for a Forward Active Clamp Converter and the Investigation of Integratable Lateral Power Devices

    Dong, Wei

    1997-01-01

    In Part I, the design of an ASIC control chip for a forward active clamp converter is presented. Integration of the control and drive circuit into one IC chip results in higher power density, higher reliability for the converter module. The designed ASIC control chip uses a 2.0 um N well Analog CMOS process, and is fabricated at MOSIS. The design procedures of the ASIC chip are explained, and experimental results are presented. Part II of the thesis focuses on the numerical investigat...

  14. Radiation tolerant power converter controls

    Todd, B; King, Q; Uznanski, S

    2012-01-01

    The Large Hadron Collider (LHC) at the European Organisation for Nuclear Research (CERN) is the world's most powerful particle collider. The LHC has several thousand magnets, both warm and super-conducting, which are supplied with current by power converters. Each converter is controlled by a purpose-built electronic module called a Function Generator Controller (FGC). The FGC allows remote control of the power converter and forms the central part of a closed-loop control system where the power converter voltage is set, based on the converter output current and magnet-circuit characteristics. Some power converters and FGCs are located in areas which are exposed to beam-induced radiation. There are numerous radiation induced effects, some of which lead to a loss of control of the power converter, having a direct impact upon the accelerator's availability. Following the first long shut down (LS1), the LHC will be able to run with higher intensity beams and higher beam energy. This is expected to lead to signifi...

  15. Autonomous Active and Reactive Power Distribution Strategy in Islanded Microgrids

    Wu, Dan; Tang, Fen; Guerrero, Josep M.; Vasquez, Juan Carlos; Chen, Guoliang; Sun, Libing

    2014-01-01

    This paper proposes an autonomous active and reactive power distribution strategy that can be applied directly on current control mode (CCM) inverters, being compatible as well with conventional droop-controlled voltage control mode (VCM) converters. In a microgrid, since renewable energy sources (RES) units regulate different active power, the proposed reactive power distribution is adaptively controlled according to the active power distribution among energy storage systems (ESS) and RES un...

  16. Life extension activities and modernization strategies for instrumentation ampersand control systems of research and power reactors in India

    Based on three and half decades of experience gained in the operation and maintenance of Instrumentation and Control Systems of nuclear reactors in India, specific investigations were made to understand various aspects of aging. The analysis of the failure rates of various instruments, plant outage figures and obsolescence of components have necessitated the replacement of instrumentation to improve the reliability and performance. The aging models available were used to determine the extent of performance degradation and to formulate maintenance strategies. The nuclear instrumentation of the aging research reactors at Bhabha Atomic Research Centre (BARC) has been replaced with high reliability equipment using modern integrated circuits. This has resulted in an improvement in the mean time between failure (MTBF) by a factor of five. The neutronic instrumentation of Fast Breeder Test Reactor (FBTR) at Madras is currently being upgraded with the introduction of microprocessor based safety units for reactivity computation and online testing of safety logic with Fine Impulse Technique. The operating experience has also indicated the necessity of developing online surveillance methods and status monitoring of various systems to detect aging. Online cable insulation measurement technique and noise analysis methods for vibration monitoring have been developed. Campbell method of signal processing has been successfully used in extending the useful life of Local Power Range monitors in the Boiling Water Reactor at Tarapur. In order to improve reliability, accuracy and provide efficient man machine interface, microprocessor based systems with online testing features have been installed in power reactors. These include the high performance reactor regulating system and centralised radiation monitoring systems commissioned at Kakrapara power station. The paper describes the above systems and the modernization strategies for nuclear instrumentation and control

  17. Robust power system frequency control

    Bevrani, Hassan

    2014-01-01

    This updated edition of the industry standard reference on power system frequency control provides practical, systematic and flexible algorithms for regulating load frequency, offering new solutions to the technical challenges introduced by the escalating role of distributed generation and renewable energy sources in smart electric grids. The author emphasizes the physical constraints and practical engineering issues related to frequency in a deregulated environment, while fostering a conceptual understanding of frequency regulation and robust control techniques. The resulting control strategi

  18. Power Control Unit of Irecin Nanosatellite

    del Re, V.; Ferrrante, M.; Ortenzi, A.; Petrozzi, M.

    2004-08-01

    On board resources necessary to perform the mission tasks are very limited in nano-satellites. This paper proposes a real-time sub-system, which is able to manage Irecin Power Supply. Irecin power supply includes the solar panels, built with silicon solar cells, the batteries and the necessary electronic for Energy generation and distribution to its subsystems. The Power Control Unit (PCU), provided with electrical power by means of solar panels, optimises the batteries recharging using a Peek Power Tracking; generates and stabilizes the voltage of 5 V for all subsystems; checks subsystems power absorption notifying it to the main micro-processor board. The proposed subsystem controls whole satellite subsystems energy adsorption by monitoring battery recharge status and handling subsystems activation /deactivation. It allows isolating damaged subsystems which could put in short cut the nanosatellite power supply and, generally, it increases nanosatellite time-life. Moreover this configuration allows to let free the on board main microprocessor from the power control functions, increasing its communication capabilities with the others subsystems. IRECIN uses rechargeable lithium ion batteries, which ensure very high energy density reducing power system volume and weight. These batteries are characterised also by a wide temperature range, enabling a simpler thermal design and by a very low cost. All electronic components are SMD technology in order to reduce weight and size. The realized Electronic boards are completely developed, realized and tested at the Vitrociset S.P.A. under control of Research and Develop Group. The proposed sub-system is implemented on the Irecin, a modular nano-satellite weighting less than 1.5 kg, constituted by sixteen external sides with surface-mounted solar cells and three internal Al plates, kept together by four steel bars. Attitude is determined by three-axis magnetometer and the solar panels data. Control is provided by an active

  19. Power generation, operation and control

    Wood, Allen J; Sheblé, Gerald B

    2013-01-01

    Since publication of the second edition, there have been extensive changes in the algorithms, methods, and assumptions in energy management systems that analyze and control power generation. This edition is updated to acquaint electrical engineering students and professionals with current power generation systems. Algorithms and methods for solving integrated economic, network, and generating system analysis are provided. Also included are the state-of-the-art topics undergoing evolutionary change, including market simulation, multiple market analysis, multiple interchange contract analysis, c

  20. Investigation of SSR characteristics of unified power flow controller

    Padiyar, KR; Prabhu, Nagesh

    2005-01-01

    The unified power flow controller (UPFC) is the most versatile flexible ac transmission system (FACTS) controller which can be used to control active and reactive power flows in a transmission line in addition to the bus voltage. The active series compensation is provided by injecting series reactive voltage. The voltage at the two ports of UPF Care regulated by control of shunt current and series real voltage. It also has several operating control modes such as voltage and power regulation, ...

  1. Control voltage and power fluctuations when connecting wind farms

    Berinde, Ioan, E-mail: ioan-berinde@yahoo.com; Bălan, Horia, E-mail: hbalan@mail.utcluj.ro; Oros, Teodora Susana, E-mail: teodoraoros-87@yahoo.com [Technical University of Cluj-Napoca, Romania, Faculty of Electrical Engineering, Department of Power Engineering and Management (Romania)

    2015-12-23

    Voltage, frequency, active power and reactive power are very important parameters in terms of power quality. These parameters are followed when connecting any power plant, the more the connection of wind farms. Connecting wind farms to the electricity system must not cause interference outside the limits set by regulations. Modern solutions for fast and automatic voltage control and power fluctuations using electronic control systems of reactive power flows. FACTS (Flexible Alternating Current Transmision System) systems, established on the basis of power electronic circuits ensure control of electrical status quantities to achieve the necessary transfer of power to the power grid. FACTS devices can quickly control parameters and sizes of state power lines, such as impedance line voltages and phase angles of the voltages of the two ends of the line. Their use can lead to improvement in power system operation by increasing the transmission capacity of power lines, power flow control lines, improved static and transient stability reserve.

  2. Control voltage and power fluctuations when connecting wind farms

    Berinde, Ioan; Bǎlan, Horia; Oros Pop, Teodora Susana

    2015-12-01

    Voltage, frequency, active power and reactive power are very important parameters in terms of power quality. These parameters are followed when connecting any power plant, the more the connection of wind farms. Connecting wind farms to the electricity system must not cause interference outside the limits set by regulations. Modern solutions for fast and automatic voltage control and power fluctuations using electronic control systems of reactive power flows. FACTS (Flexible Alternating Current Transmision System) systems, established on the basis of power electronic circuits ensure control of electrical status quantities to achieve the necessary transfer of power to the power grid. FACTS devices can quickly control parameters and sizes of state power lines, such as impedance line voltages and phase angles of the voltages of the two ends of the line. Their use can lead to improvement in power system operation by increasing the transmission capacity of power lines, power flow control lines, improved static and transient stability reserve.

  3. Control voltage and power fluctuations when connecting wind farms

    Voltage, frequency, active power and reactive power are very important parameters in terms of power quality. These parameters are followed when connecting any power plant, the more the connection of wind farms. Connecting wind farms to the electricity system must not cause interference outside the limits set by regulations. Modern solutions for fast and automatic voltage control and power fluctuations using electronic control systems of reactive power flows. FACTS (Flexible Alternating Current Transmision System) systems, established on the basis of power electronic circuits ensure control of electrical status quantities to achieve the necessary transfer of power to the power grid. FACTS devices can quickly control parameters and sizes of state power lines, such as impedance line voltages and phase angles of the voltages of the two ends of the line. Their use can lead to improvement in power system operation by increasing the transmission capacity of power lines, power flow control lines, improved static and transient stability reserve

  4. Formation of the active medium in high-power repetitively pulsed gas lasers pumped by an electron-beam-controlled discharge

    Bulaev, V. D.; Lysenko, S. L.

    2015-07-01

    A high-power repetitively pulsed e-beam-controlled discharge CO2 laser is simulated numerically; the simulation results are compared with experimental data. Optimal sizes and design of electrodes and configuration of the external magnetic field are found, which allow one to introduce no less than 90% electric pump energy into a specified volume of the active medium, including the active volume of a laser with an aperture of 110 × 110 cm. The results obtained can also be used to design other types of highpower gas lasers.

  5. Adaptive controlling of power boiler

    Wojcik, W.; Kalita, M; Smolarz, A.

    2004-01-01

    This paper presents research on adaptive control (AC) of combastion process in in¬dustry. Results were obtained from research conducted in laboratory combustion chamber with usage of Fiber Optical Measurement System (FOMS) with electronic block. Simulation proved that implementing AC and FOMS to burning process improves flue gasses parameters -direct measure of power boiler ecologic and economical quality of work.

  6. Wind power integration into the automatic generation control of power systems with large-scale wind power

    Basit, Abdul; Hansen, Anca Daniela; Altin, Müfit;

    2014-01-01

    Transmission system operators have an increased interest in the active participation of wind power plants (WPP) in the power balance control of power systems with large wind power penetration. The emphasis in this study is on the integration of WPPs into the automatic generation control (AGC) of...

  7. Development of novel activated carbon-based adsorbents for the control of mercury emissions from coal-fired power plants

    Radisav D. Vidic

    1999-03-01

    In addition to naturally occurring mercury sources, anthropogenic activities increase the mercury loading to the environment. Although not all produced mercury is dissipated directly into the environment, only minor portions of the total production are stocked or recycled, and the rest of the mercury and its compounds is finally released in some way into atmosphere, surface waters and soil, or ends in landfills dumps, and refuse. Since mercury and its compounds are highly toxic, their presence in the environment constitutes potential impact on all living organisms, including man. The first serious consequence of industrial mercury discharges causing neurological disorder even death occurred in Minimata, Japan in 1953. Systematic studies showed that mercury poisoning is mainly found in fish-eating populations. However, various levels of mercury are also found in food other than fish. During the past several decades, research has been conducted on the evaluation of risks due to exposure to mercury and the development of control technologies for mercury emissions. In 1990, the Clean Air Act Amendments listed mercury, along with 10 other metallic species, as a hazardous air pollutant (HAP). This has further stimulated research for mercury control during the past several years. The impact of mercury on humans, sources of mercury in the environment, current mercury control strategies and the objective of this research are discussed in this section.

  8. Power system dynamics and control

    Kwatny, Harry G

    2016-01-01

    This monograph explores a consistent modeling and analytic framework that provides the tools for an improved understanding of the behavior and the building of efficient models of power systems. It covers the essential concepts for the study of static and dynamic network stability, reviews the structure and design of basic voltage and load-frequency regulators, and offers an introduction to power system optimal control with reliability constraints. A set of Mathematica tutorial notebooks providing detailed solutions of the examples worked-out in the text, as well as a package that will enable readers to work out their own examples and problems, supplements the text. A key premise of the book is that the design of successful control systems requires a deep understanding of the processes to be controlled; as such, the technical discussion begins with a concise review of the physical foundations of electricity and magnetism. This is followed by an overview of nonlinear circuits that include resistors, inductors, ...

  9. Integrated Coordinated Optimization Control of Automatic Generation Control and Automatic Voltage Control in Regional Power Grids

    Qiu-Yu Lu; Wei Hu; Le Zheng; Yong Min; Miao Li; Xiao-Ping Li; Wei-Chun Ge; Zhi-Ming Wang

    2012-01-01

    Automatic Generation Control (AGC) and Automatic Voltage Control (AVC) are key approaches to frequency and voltage regulation in power systems. However, based on the assumption of decoupling of active and reactive power control, the existing AGC and AVC systems work independently without any coordination. In this paper, a concept and method of hybrid control is introduced to set up an Integrated Coordinated Optimization Control (ICOC) system for AGC and AVC. Concerning the diversity of contro...

  10. Autonomous Active and Reactive Power Distribution Strategy in Islanded Microgrids

    Wu, Dan; Tang, Fen; Guerrero, Josep M.;

    2014-01-01

    This paper proposes an autonomous active and reactive power distribution strategy that can be applied directly on current control mode (CCM) inverters, being compatible as well with conventional droop-controlled voltage control mode (VCM) converters. In a microgrid, since renewable energy sources...... (RES) units regulate different active power, the proposed reactive power distribution is adaptively controlled according to the active power distribution among energy storage systems (ESS) and RES units. The virtual impedance is implemented in order to improve the reactive power sharing in a...... distributed way. Real-time hardware-in-the-loop results are presented to verify the proposed control strategy....

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

    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...... strategies are able to achieve load shifting and enable end users to participate in market-based power systems, and thus profit from optimal consumption of energy in relation to price and supply of ancillary services in the power system, as well as improve grids with integration of high penetration of...

  12. Design of Controller for New EAST Fast Control Power Supply

    The effectiveness of the magnetic confinement of plasma can be improved by elongating the plasma cross-section in tokamak devices. But elongated plasma has vertical displacement instability, so a feedback control system is needed to restrain the plasma's vertical displacement. A fast control power supply is needed to excite the active feedback coils, which produces a magnetic field to control the plasma's displacement. With the development of EAST, the fast control power supply needs to keep on enhancing the fast response and output current. The structure of a new power supply is introduced in this paper. The method of multiple inverters paralleled with the current sharing reactor is presented to meet the need for large current and fast control. According to the design demands of the EAST fast control power supply, the adjuster of the current close loop is applied to the inverter, which can advance its ability to restrain the loop current in low frequency and DC output. The result of the experiment confirms the validity of the proposed scheme and control strategy. (fusion engineering)

  13. Nuclear reactor power control device

    When occurrence of earthquakes is judged in a BWR type reactor, the power is decreased by inserting a portion of control rods, reducing a speed of recycling pumps, stopping recycling pumps, increasing the opening degree of a main steam control valve and opening a main steam relief valve. The reactor scram can be avoided by bypassing neutron flux high signal, settling a filter to neutron flux signals and setting a reactor scram set value by neutron flux signals, for example, to 120%. There is constituted an interlock for performing reactor scram when both of a neutron flux high signal and a signal outputted if a surface heat flux corresponding signal formed by applying calculation to the neutron flux high signal exceeds a set value are valid, to avoid unnecessary reactor scram. As a measuring means, not only an acceleration meter in the power plant, but also acceleration meters at remote places, acceleration meters or displacement meters for various kinds of equipments in the power plant are used, and when signals from them exceed set values, earthquake judgement is conducted. (N.H.)

  14. Automatic reactor power control device

    Anticipated transient without scram (ATWS) of a BWR type reactor is judged to generate a signal based on a reactor power signal and a scram actuation demand signal. The ATWS signal and a predetermined water level signal to be generated upon occurrence of ATWS are inputted, and an injection water flow rate signal exhibiting injection water flow rate optimum to reactor flooding and power suppression is outputted. In addition, a reactor pressure setting signal is outputted based on injection performance of a high pressure water injection system or a lower pressure water injection system upon occurrence of ATWS. Further, the reactor pressure setting signal is inputted to calculate opening/closing setting pressure of a main steam relief valve and output an opening setting pressure signal and a closure setting pressure signal for the main steam relief valve. As a result, the reactor power and the reactor water level can be automatically controlled even upon occurrence of ATWS due to failure of insertion of all of the control rods thereby enabling to maintain integrity and safety of the reactor, the reactor pressure vessel and the reactor container. (N.H.)

  15. Dynamic model of frequency control in Danish power system with large scale integration of wind power

    Basit, Abdul; Hansen, Anca Daniela; Sørensen, Poul Ejnar

    2013-01-01

    This work evaluates the impact of large scale integration of wind power in future power systems when 50% of load demand can be met from wind power. The focus is on active power balance control, where the main source of power imbalance is an inaccurate wind speed forecast. In this study, a Danish...... power system model with large scale of wind power is developed and a case study for an inaccurate wind power forecast is investigated. The goal of this work is to develop an adequate power system model that depicts relevant dynamic features of the power plants and compensates for load generation...

  16. Control of power plants and power systems. Proceedings

    The 88 papers in this volume constitute the proceedings of the International Federation of Automatic Control Symposium held in Mexico in 1995. The broad areas which they cover are: self tuning control; power plant operations; dynamic stability; fuzzy logic applications; power plants modelling; artificial intelligence applications; power plants simulation; voltage control; control of hydro electric units; state estimation; fault diagnosis and monitoring systems; system expansion and operation planning; security assessment; economic dispatch and optimal load flow; adaptive control; distribution; transient stability and preventive control; modelling and control of nuclear plant; knowledge data bases for automatic learning methods applied to power system dynamic security assessment; control of combined cycle units; power control centres. Separate abstracts have been prepared for the three papers relating to nuclear power plants. (UK)

  17. Power Control Scheme of D-Statcom

    A. Sai Krishna,

    2014-06-01

    Full Text Available This paper presents an instantaneous power control scheme of D-STATCOM for power factor and harmonic compensation. The control strategy has been introduced in order to enhance some steady-state performances and elimination of power quality disturbances. Power factor and harmonic current of a controlled feeder section are two vital roles in steady-state power distribution system operation. In this paper, a control scheme with constant power and sinusoidal current compensation is exploited. And the proposed control scheme is designed to correct the power factor. In order to correct the power factor, a power factor control loop is required and therefore included in the control block. The DC voltage across the DC link capacitor must be large enough and kept constant at that value to stabilize the compensation. Therefore, DC link voltage regulator must be added to the control loop. Simulation is performed in two cases.

  18. Wireless power charging using point of load controlled high frequency power converters

    Miller, John M.; Campbell, Steven L.; Chambon, Paul H.; Seiber, Larry E.; White, Clifford P.

    2015-10-13

    An apparatus for wirelessly charging a battery of an electric vehicle is provided with a point of load control. The apparatus includes a base unit for generating a direct current (DC) voltage. The base unit is regulated by a power level controller. One or more point of load converters can be connected to the base unit by a conductor, with each point of load converter comprising a control signal generator that transmits a signal to the power level controller. The output power level of the DC voltage provided by the base unit is controlled by power level controller such that the power level is sufficient to power all active load converters when commanded to do so by any of the active controllers, without generating excessive power that may be otherwise wasted.

  19. Usefullness of under controlled powers

    In the view of production of the energy with the aspect of healthy, confidential, sustainable and profitable; severity of the nuclear energy directly realized rather than alternative energies. There are a lot of studies holds on the purpose of preferring to use pure energy resources rather fossil resources of patrol to satisfy the energy demand. Hydrogen usage at the transportation, heating and energy applications should prefer than fossil fuels. Also production of the hydrogen from a nuclear power resource by the cost-effective way is important to the project of a clean world. Turkey should also benefit from that energy among 30 countries in the world take its advantages. On the other hand putting on the agenda of bad experiences at the nuclear energy applications, technical problems, which are possible for all another applications, should not be barrier improvements at that area. We can not warm up in the Turkey. We have not got enough money. We feel cold... Human being misses to be accustomed life standards. For this reason keeping away from nuclear energy's opportunity looks like keeping away from civilization. That is accepting live in dark ages. This energy's safety usage requires education and technology Production of this energy brings potential and strategic power to the country. Power should produced and used if it is controlled. First controlling way is having well educated brains, scientific methodology and technology that is satisfy this control. After that producing energy appropriate process with control. Passing to the charcoal from wood heating from charcoal to patrol and stop there, is likely a case as failing as at the civilization class. Countries could become civilized as they worked and deserved. Turkey is in a geopolitical and geo strategical geography between the Balkans and Middle East. She's also a bridge between Europe and Asia regarding exchange of cultures, civilization and industrialization. As an important developing country in the

  20. The Power Quality Compensation Strategy for Power Distribution System Based on Hybrid Parallel Active Power Filters

    Rachid DEHINI

    2010-12-01

    Full Text Available In this paper, the main aim is to confront the performance of shunt active power filter (SAPF and the shunt hybrid active power filter (SHAPF to achieve flexibility and reliability of the filter devices. Both of the two devices used the classical proportional-integral controller for pulse generation to trigger the inventers MOSFET’s. In the adopted hybrid active filter there is a passive power filter with high power rating to filter the low order harmonies and one active filter with low power rating to filter the other high order harmonies. In order to investigate the effectiveness of (SHAPF, the studies have been accomplished using simulation with the MATLAB-SIMULINK. The results show That (SHAPF is more effective than (SAPF, and has lower cost.

  1. New Control Strategy of Hybrid Power Filter

    Škramlík, Jiří; Valouch, Viktor

    Madeira : APDEE, 2007, s. 1-6. ISBN 978-972-8822-08-8. [ Portuguese -Spanish Conference in Electrical Engineering - XCLEEE /10./. Madeira (PT), 05.07.2007-07.07.2007] R&D Projects: GA ČR GA102/06/0112 Institutional research plan: CEZ:AV0Z20570509 Keywords : active power filters * feedback and feedforward control strategy * unsymetrical and non-sinusoidal voltage system Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering

  2. Novel Active Combustion Control Valve

    Caspermeyer, Matt

    2014-01-01

    This project presents an innovative solution for active combustion control. Relative to the state of the art, this concept provides frequency modulation (greater than 1,000 Hz) in combination with high-amplitude modulation (in excess of 30 percent flow) and can be adapted to a large range of fuel injector sizes. Existing valves often have low flow modulation strength. To achieve higher flow modulation requires excessively large valves or too much electrical power to be practical. This active combustion control valve (ACCV) has high-frequency and -amplitude modulation, consumes low electrical power, is closely coupled with the fuel injector for modulation strength, and is practical in size and weight. By mitigating combustion instabilities at higher frequencies than have been previously achieved (approximately 1,000 Hz), this new technology enables gas turbines to run at operating points that produce lower emissions and higher performance.

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

    Yap Hoon

    2016-07-01

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

  4. Design of power control system using SMES and SVC for fusion power plant

    Niiyama, K; Yagai, T; Tsuda, M; Hamajima, T [Graduate school of Engineering, Tohoku University, Sendai (Japan)], E-mail: kniiyama@ecei.tohoku.ac.jp

    2008-02-15

    A SMES (Superconducting Magnetic Energy Storage System) system with converter composed of self-commutated valve devices such as GTO and IGBT is available to control active and reactive power simultaneously. A SVC (Static Var Compensators) or STATCOM (Static Synchronous Compensator) is widely employed to reduce reactive power in power plants and substations. Owing to progress of power electronics technology using GTO and IGBT devices, power converters in the SMES system and the SVC can easily control power flow in few milliseconds. Moreover, since the valve devices for the SMES are equivalent to those for the SVC, the device cost must be reduced. In this paper the basic control system combined with the SMES and SVC is designed for large pulsed loads of a nuclear fusion power plant. This combined system largely expands the reactive power control region as well as the active one. The simulation results show that the combined system is effective and prospective for the nuclear fusion power plant.

  5. Three-Phase Power Factor Controller

    Nola, F. J.

    1982-01-01

    Three-Phase Power-Factor Controller develops a control signal for each motor winding. As motor loading decreases, rms value of applied voltage is decreased by feedback-control circuit. Power consumption is therefore lower than in unregulated operation. Controller employs phase detector for each of three phases of delta-connected induction motor. Phase-difference sum is basis for control.

  6. Power control system and method

    Steigerwald, Robert Louis; Anderson, Todd Alan

    2006-11-07

    A power system includes an energy harvesting device, a battery coupled to the energy harvesting device, and a circuit coupled to the energy harvesting device and the battery. The circuit is adapted to deliver power to a load by providing power generated by the energy harvesting device to the load without delivering excess power to the battery and to supplement the power generated by the energy harvesting device with power from the battery if the power generated by the energy harvesting device is insufficient to fully power the load. A method of operating the power system is also provided.

  7. Advanced Coordinating Control System for Power Plant

    WU Peng; WEI Shuangying

    2006-01-01

    The coordinating control system is popular used in power plant. This paper describes the advanced coordinating control by control methods and optimal operation, introduces their principals and features by using the examples of power plant operation. It is wealthy for automation application in optimal power plant operation.

  8. CCLIBS: The CERN Power Converter Control Libraries

    AUTHOR|(SzGeCERN)404953; Lebioda, Krzysztof Tomasz; Magrans De Abril, Marc; Martino, Michele; Murillo Garcia, Raul; Nicoletti, Achille

    2015-01-01

    Accurate control of power converters is a vital activity in large physics projects. Several different control scenarios may coexist, including regulation of a circuit’s voltage, current, or field strength within a magnet. Depending on the type of facility, a circuit’s reference value may be changed asynchronously or synchronously with other circuits. Synchronous changes may be on demand or under the control of a cyclic timing system. In other cases, the reference may be calculated in real-time by an outer regulation loop of some other quantity, such as the tune of the beam in a synchrotron. The power stage may be unipolar or bipolar in voltage and current. If it is unipolar in current, it may be used with a polarity switch. Depending on the design, the power stage may be controlled by a firing angle or PWM duty-cycle reference, or a voltage or current reference. All these cases are supported by the CERN Converter Control Libraries (CCLIBS). These open-source C libraries include advanced reference generati...

  9. 单相有源PFC开环控制的研究%Research on Open Loop Control of Single-Phase Active Power Factor Corrector

    江剑峰; 杨喜军; 蒋婷; 曹中圣

    2012-01-01

    By now, in the field of single-phase active power factor correctors (PFC) , there are many control methods, which can be summarized into open control and closed control with their different merits and applicable scopes. In the paper, on the basis of the analysis of a single-phase active PFC principle needless of output voltage detection, an open loop control strategy is presented and analyzed only needing detection of post-bridge sinusoidal half-wave voltage, which can bring about follower characteristics versus input voltage and output power by means of regulation of the ratio between the mean output voltage and the RMS input voltage, and can also maintain the mean output voltage. After the simulation analysis by MATLAB/SIMULINK, a single-phase active PFC open digital control circuit based on DSP TMS320F28335 is designed and built into experimental platform and tested. The gained simulation and implementation results prove the theoretical analysis.%在单相有源PFC领域,截止目前,出现了多种控制方法,可以归类于开环控制和闭环控制,各有优缺点和所适用范围.在分析一种无需输出电压检测的单相PFC控制原理的基础上,提出和分析了一种只需检测整流桥后正弦半波电压和输出阻抗的开环控制策略,适合单级有源PFC和多级交错有源PFC,通过调节输出电压平均值与输入电压有效值之比,可以获得输出电压相对输入电压或输出功率的跟随特性,也可以维持输出电压平均值不变,在利用MATLAB/Simulink仿真分析后,基于DSPTMS320F28335设计了一种单相有源PFC的开环数字控制电路,建立实验平台进行实验测试.所得的仿真与实验结果符合相关的理论分析.

  10. The Real-Time Research of Optimal Power Flow Calculation in Reduce Active Power Loss Aspects of Power Grid

    Yuting Pan; Yuchen Chen; Zhiqiang Yuan; Bo Liu

    2015-01-01

    In order to research how to availably reduce the active power loss value in power grid system when the power system is operating, it offers a quantitative research in theory through conceiving the unbalanced losses of power grid system under the overloading bus as the investigative object, and establishing an active power loss mathematical model. It carries out online real-time optimal flow calculation within the condition that meets the control variables and state variables of the equality a...

  11. Wind power integration into the automatic generation control of power systems with large-scale wind power

    Abdul Basit

    2014-10-01

    Full Text Available Transmission system operators have an increased interest in the active participation of wind power plants (WPP in the power balance control of power systems with large wind power penetration. The emphasis in this study is on the integration of WPPs into the automatic generation control (AGC of the power system. The present paper proposes a coordinated control strategy for the AGC between combined heat and power plants (CHPs and WPPs to enhance the security and the reliability of a power system operation in the case of a large wind power penetration. The proposed strategy, described and exemplified for the future Danish power system, takes the hour-ahead regulating power plan for generation and power exchange with neighbouring power systems into account. The performance of the proposed strategy for coordinated secondary control is assessed and discussed by means of simulations for different possible future scenarios, when wind power production in the power system is high and conventional production from CHPs is at a minimum level. The investigation results of the proposed control strategy have shown that the WPPs can actively help the AGC, and reduce the real-time power imbalance in the power system, by down regulating their production when CHPs are unable to provide the required response.

  12. Power flow control using quadrature boosters

    Sadanandan, Sandeep N.

    A power system that can be controlled within security constraints would be an advantage to power planners and real-time operators. Controlling flows can lessen reliability issues such as thermal limit violations, power stability problems, and/or voltage stability conditions. Control of flows can also mitigate market issues by reducing congestion on some lines and rerouting power to less loaded lines or onto preferable paths. In the traditional control of power flows, phase shifters are often used. More advanced methods include using Flexible AC Transmission System (FACTS) Controllers. Some examples include Thyristor Controlled Series Capacitors, Synchronous Series Static Compensators, and Unified Power Flow Controllers. Quadrature Boosters (QBs) have similar structures to phase-shifters, but allow for higher voltage magnitude during real power flow control. In comparison with other FACTS controllers QBs are not as complex and not as expensive. The present study proposes to use QBs to control power flows on a power system. With the inclusion of QBs, real power flows can be controlled to desired scheduled values. In this thesis, the linearized power flow equations used for power flow analysis were modified for the control problem. This included modifying the Jacobian matrix, the power error vector, and calculating the voltage injected by the quadrature booster for the scheduled real power flow. Two scenarios were examined using the proposed power flow control method. First, the power flow in a line in a 5-bus system was modified with a QB using the method developed in this thesis. Simulation was carried out using Matlab. Second, the method was applied to a 30-bus system and then to a 118-bus system using several QBs. In all the cases, the calculated values of the QB voltages led to desired power flows in the designated line.

  13. Active screening of magnetic field near power stations generator buses

    B.I. Kuznetsov

    2013-12-01

    Full Text Available An experimental study technique for a prototyping system of active screening of power-frequency magnetic field distortions near power station generator buses via controllable magnetic field sources is presented. Results of experimental research on a proto-typing active screening system with different control algorithms are given.

  14. Computerized control and management at the Temelin nuclear power plant

    The proposed automation of the nuclear power plant control system includes a division of the control system into three hierarchic levels, supplemented with an additional level. These comprise the automated system of control of technological processes, the all-plant control of the power-generating process, the control of backup activities and of technical and economic activities, and top managerial control. The efficiency of the nuclear power plant operation, i.e. attainment of the maximum electricity output with minimum costs while securing the required safety, is the principal criterion in the design of the data model. Listed are tasks that would lend themselves to automation within the automated system of nuclear power plant control, and the basic scheme of their automation as follows from an analysis performed at the Temelin nuclear power plant. (Z.S). 2 figs., 2 refs

  15. Hierarchical power control of multiterminal HVDC grids

    Egea Àlvarez, Agustí; Beerten, Jef; van Hertem, Dirk; Gomis Bellmunt, Oriol

    2015-01-01

    This article introduces a hierarchical power control structure for Multi-terminal High Voltage Direct Current (MT-HVDC) systems. The presented hierarchy is similar to the control structure used in classical AC transmission systems and is divided in primary, secondary and tertiary control actions. The voltage control in the MT-HVDC scheme acts in a way similar to the primary control action of generators in AC systems, while the secondary control action is performed by an outer power control lo...

  16. Water Turbine Power Control - Feasible Conception

    Němec, Zdeněk; Němec, Vojtěch

    2009-01-01

    This paper is concerned with Francis water turbine power control issue. There are introduced six conceptions of power controllers and corresponding control loop features are discussed. The control features are illustrated with step responses and the major attention is paid to the undesirable under-control effect. On an example of control system with an elementary description and with relatively short turbine pipeline feeder are the control features compared.

  17. An novel analog programmable power supply for active gain control of the Multi-Pixel Photon Counter (MPPC)

    Li, Zhengwei; Xu, Yupeng; Yan, Bo; Li, Yanguo; Lu, Xuefeng; Li, Xufang; Zhang, Shuo; Chang, Zhi; Li, Jicheng; Zhang, Yifei; Zhao, Jianling

    2016-01-01

    Silicon Photo-Multipliers (SiPM) are regarded as novel photo-detector to replace conventional Photo-Multiplier Tubes (PMTs). However, the breakdown voltage dependence on the ambient temperature results in a gain variation of $\\sim$3$\\% /^{\\circ} \\mathrm C$. This can severely limit the application of this device in experiments with wide range of operating temperature, especially in space telescope. An experimental setup in dark condition was established to investigate the temperature and bias voltage dependence of gain for the Multi-Pixel Photon Counter (MPPC), one type of the SiPM developed by Hamamatsu. The gain and breakdown voltage dependence on operating temperature of an MPPC can be approximated by a linear function, which is similar to the behavior of a zener diode. The measured temperature coefficient of the breakdown voltage is $(59.4 \\pm 0.4$ mV)$/^{\\circ} \\mathrm C$. According to this fact, a programmable power supply based on two zener diodes and an operational amplifier was designed with a positiv...

  18. Control of renewable distributed power plants

    Bullich Massagué, Eduard

    2015-01-01

    The main objective of this master thesis is to design a power plant controller for a photo- voltaic (PV) power plant. In a first stage, the current situation of the status of the electrical grid is analysed. The electrical network structure is moving from a conventional system (with centralized power generation, unidirectional power ows, easy control) to a smart grid system consisting on distributed generation, renewable energies, smart and complex control architecture and ...

  19. Control power in perfect controlled teleportation via partially entangled channels

    Li, Xi-Han; Ghose, Shohini

    2014-01-01

    We analyze and evaluate perfect controlled teleportation via three-qubit entangled channels from the point of view of the controller. The key idea in controlled teleportation is that the teleportation is performed only with the participation of the controller. We calculate a quantitative measure of the controller's power and establish a lower bound on the control power required for controlled teleportation. We show that the maximally entangled GHZ state is a suitable channel for controlled te...

  20. Nuclear Power Plant Control and Instrumentation 1989

    The meeting of the International Working Group on Nuclear Power Plant Control and Instrumentation (IWG-NPPCI) was organized in order to summarize operating experience of nuclear power plant control systems, gain a general overview of activities in development of modern control systems and receive recommendations on the further directions and particular measures within the Agency's programme. The meeting was held at the IAEA Headquarters in Vienna and was attended by 21 national delegates and observers from 18 countries. The present volume contains: (1) report on the meeting of the IWG-NPPCI, Vienna, 8-10 May 1989, (2) report of the scientific secretary on the major activities of IAEA during 1987-89 in the NPPCI area, (3) terms of reference International Working Group on NPPCI and (4) reports of the national representatives to the International Working Group on NPPCI. The paper and discussions with practical experience and described actual problems encountered. Emphasis was placed on the technical, industrial and economical aspects of the introduction of modern control systems and on the improvement of plant availability and safety. A separate abstract was prepared for each of the 19 papers presented by members of the International Working Group. Refs, figs and tabs

  1. Power, thermal, and attitude control design interactions of the CCE/AMPTE spacecraft. [Charge Composition Explorer/Active Magnetospheric Particle Tracer Explorers

    Wingate, C. A., Jr.; Allen, W. E.; Smola, J. F.; Ray, J. C.

    1982-01-01

    The power, thermal and attitude control interactions of the CCE spacecraft and the design compromises resulting from these interactions are described. These compromises result from the conflict between the plane change maneuver requirements and the final on station requirements. The resolution of these conflicts to arrive at an acceptable final design, is given and the resulting power, thermal and attitude control systems are described in some detail.

  2. High-power active devices

    Carroll, E

    2006-01-01

    Very high-power (HP) electronics represents a small part of the electronics market. In semiconductor terms, HP represents a world device market of 600 million euros out of a total 200 billion euros for all semiconductors—a mere 0.3 per cent. At the multi-megawatt spectral end, the numbers are even smaller, so that it is quite common for electronics engineers to be unaware of developments in Very High Power (VHP). In this presentation we discuss the categories of VHP active devices, the basic topologies in which they operate, and the trend towards higher voltage and current. New press-pack technologies are introduced and the salient differences between Insulated Gate Bipolar Transistors (IGBTs) and Integrated Gate Commutated Thyristors (IGCTs) are compared. Finally, recent developments in turn-off ratings for both these devices are presented.

  3. Integrated Coordinated Optimization Control of Automatic Generation Control and Automatic Voltage Control in Regional Power Grids

    Qiu-Yu Lu

    2012-09-01

    Full Text Available Automatic Generation Control (AGC and Automatic Voltage Control (AVC are key approaches to frequency and voltage regulation in power systems. However, based on the assumption of decoupling of active and reactive power control, the existing AGC and AVC systems work independently without any coordination. In this paper, a concept and method of hybrid control is introduced to set up an Integrated Coordinated Optimization Control (ICOC system for AGC and AVC. Concerning the diversity of control devices and the characteristics of discrete control interaction with a continuously operating power system, the ICOC system is designed in a hierarchical structure and driven by security, quality and economic events, consequently reducing optimization complexity and realizing multi-target quasi-optimization. In addition, an innovative model of Loss Minimization Control (LMC taking into consideration active and reactive power regulation is proposed to achieve a substantial reduction in network losses and a cross iterative method for AGC and AVC instructions is also presented to decrease negative interference between control systems. The ICOC system has already been put into practice in some provincial regional power grids in China. Open-looping operation tests have proved the validity of the presented control strategies.

  4. Power System Stability Enhancement Using Unified Power Flow Controller

    Prechanon Kumkratug

    2010-01-01

    Full Text Available Problem statement: The enhancement of transient stability of the power system is one of the most challenging research areas in power engineer. Approach: This study presents the method to enhance transient stability of power system by Unified Power Flow Controller (UPFC. The mathematical model of power system equipped with a UPFC is systematically derived. The parameters of UPFC are modeled into power flow equation and thus it is used to determine control strategy. The swing curves of the three phase faulted power system without and with a UPFC are tested and compared in various cases. Results: The swing curve of system without a UPFC gets increases monotonically and thus the system can be considered as unstable whereas the swing curves of system with a UPFC can return to stable equilibrium point. Conclusion: From the simulation results, the UPFC can enhance transient stability of power system.

  5. Active weld control

    Powell, Bradley W.; Burroughs, Ivan A.

    1994-01-01

    Through the two phases of this contract, sensors for welding applications and parameter extraction algorithms have been developed. These sensors form the foundation of a weld control system which can provide action weld control through the monitoring of the weld pool and keyhole in a VPPA welding process. Systems of this type offer the potential of quality enhancement and cost reduction (minimization of rework on faulty welds) for high-integrity welding applications. Sensors for preweld and postweld inspection, weld pool monitoring, keyhole/weld wire entry monitoring, and seam tracking were developed. Algorithms for signal extraction were also developed and analyzed to determine their application to an adaptive weld control system. The following sections discuss findings for each of the three sensors developed under this contract: (1) weld profiling sensor; (2) weld pool sensor; and (3) stereo seam tracker/keyhole imaging sensor. Hardened versions of these sensors were designed and built under this contract. A control system, described later, was developed on a multiprocessing/multitasking operating system for maximum power and flexibility. Documentation for sensor mechanical and electrical design is also included as appendices in this report.

  6. The electric power engineering handbook power system stability and control

    Grisby, Leonard L

    2012-01-01

    With contributions from worldwide leaders in the field, Power System Stability and Control, Third Edition (part of the five-volume set, The Electric Power Engineering Handbook) updates coverage of recent developments and rapid technological growth in essential aspects of power systems. Edited by L.L. Grigsby, a respected and accomplished authority in power engineering, and section editors Miroslav Begovic, Prabha Kundur, and Bruce Wollenberg, this reference presents substantially new and revised content. Topics covered include: * Power System Protection * Power System Dynamics and Stability *

  7. Coordination of baseload power plant group control with static reactive power compensator control

    Zbigniew Szczerba

    2012-06-01

    Full Text Available Reactive power sources in power system nodes: generators and static reactive power compensators, are controlled by control systems. Generators – by generator node group controllers, compensators – by voltage controllers. The paper presents issues of these control systems’ coordination and proposals for its implementation.

  8. Analysis of Interline Power Flow Controller (IPFC Location in Power Transmission Systems

    Amir Kahyaei

    2011-07-01

    Full Text Available The Interline Power Flow Controller (IPFC is one of the latest generation Flexible AC Transmission Systems (FACTS controller used to control power flows of multiple transmission lines. The aim of this paper is investigation of the effect of location of IPFC on profile of voltage and real and reactive power flow in transmission lines in power system. This model is incorporated in Newton- Raphson (NR power flow algorithm to study the power flow control in transmission lines in which IPFC is placed. A program in MATLAB/SIMULINK has been written in order to extend conventional NR algorithm based on this model. Numerical results are carried out on a standard power system. The results without and with IPFC for various locations are compared in terms of voltages, active and reactive power flows to demonstrate the performance of the IPFC model.

  9. Statistical Performances of Resistive Active Power Splitter

    Lalléchère, Sébastien; Ravelo, Blaise; Thakur, Atul

    2016-03-01

    In this paper, the synthesis and sensitivity analysis of an active power splitter (PWS) is proposed. It is based on the active cell composed of a Field Effect Transistor in cascade with shunted resistor at the input and the output (resistive amplifier topology). The PWS uncertainty versus resistance tolerances is suggested by using stochastic method. Furthermore, with the proposed topology, we can control easily the device gain while varying a resistance. This provides useful tool to analyse the statistical sensitivity of the system in uncertain environment.

  10. Application of PQR Theory for control of a 3-phase 4-wire 4-legs shunt active power filter in the aß?-axes using 3D-SVM technique

    Ali CHEBABHI

    2015-05-01

    Full Text Available This article discusses and compares two control strategies applied to a 3-phase 4-wire 4-leg shunt active power filter. These two control strategies, including the cross-vector theory called CV theory and the direct method called PQR theory, are based on the instantaneous control of active and reactive power. On one hand, it is shown that, in some cases, cross-vector theory requires elimination of the zero sequence currents in a 3-phase 4-wire 4-leg shunt active power filter, which needs a power storage element, and on the other hand pretreatment system voltage is necessary to obtain compensated sinusoidal current and a degree of freedom. By relying on the cross-vector theory, the PQR theory is used to extract and remove harmonic currents components. In this control technique, there are two internal current control loops and an external voltage control loop, these control loops have been realized by PI controllers when applied 3D-SVM of switching technique. We choose as criteria for comparison the transient and the Total Harmonic Distortion in the line current. A series of simulations in MATLAB/ Simulink environment have been presented and discussed to show the performance of the two control strategies.

  11. Linguistic control of a nuclear power plant

    A multivariable linguistic controller based on fuzzy set theory is discussed and its application to a pressurized water nuclear power plant control is illustrated by computer simulation. The nonlinear power plant simulation model has nine states, two control inputs, one disturbance input, and two outputs. Although relatively simple, the model captures the essential coupled nonlinear plant dynamics and is convenient to use for control system studies. The use of an adaptive version of the controller is also demonstrated by computer simulation

  12. Modular control of fusion power heating applications

    Demers, D. R.

    2012-08-24

    This work is motivated by the growing demand for auxiliary heating on small and large machines worldwide. Numerous present and planned RF experiments (EBW, Lower Hybrid, ICRF, and ECH) are increasingly complex systems. The operational challenges are indicative of a need for components of real-time control that can be implemented with a moderate amount of effort in a time- and cost-effective fashion. Such a system will improve experimental efficiency, enhance experimental quality, and expedite technological advancements. The modular architecture of this control-suite serves multiple purposes. It facilitates construction on various scales from single to multiple controller systems. It enables expandability of control from basic to complex via the addition of modules with varying functionalities. It simplifies the control implementation process by reducing layers of software and electronic development. While conceived with fusion applications in mind, this suite has the potential to serve a broad range of scientific and industrial applications. During the Phase-I research effort we established the overall feasibility of this modular control-suite concept. We developed the fundamental modules needed to implement open-loop active-control and demonstrated their use on a microwave power deposition experiment.

  13. Modular control of fusion power heating applications

    This work is motivated by the growing demand for auxiliary heating on small and large machines worldwide. Numerous present and planned RF experiments (EBW, Lower Hybrid, ICRF, and ECH) are increasingly complex systems. The operational challenges are indicative of a need for components of real-time control that can be implemented with a moderate amount of effort in a time- and cost-effective fashion. Such a system will improve experimental efficiency, enhance experimental quality, and expedite technological advancements. The modular architecture of this control-suite serves multiple purposes. It facilitates construction on various scales from single to multiple controller systems. It enables expandability of control from basic to complex via the addition of modules with varying functionalities. It simplifies the control implementation process by reducing layers of software and electronic development. While conceived with fusion applications in mind, this suite has the potential to serve a broad range of scientific and industrial applications. During the Phase-I research effort we established the overall feasibility of this modular control-suite concept. We developed the fundamental modules needed to implement open-loop active-control and demonstrated their use on a microwave power deposition experiment

  14. Control Architecture for Future Power Systems

    Heussen, Kai

    This project looks at control of future electric power grids with a high proportion of wind power and a large number of decentralized power generation, consumption and storage units participating to form a reliable supply of electrical energy. The first objective is developing a method for...... assessment of control architecture of electric power systems with a means-ends perspective. Given this purpose-oriented understanding of a power system, the increasingly stochastic nature of this problem shall be addressed and approaches for robust, distributed control will be proposed and analyzed. The...

  15. Optically powered active sensing system for Internet Of Things

    Gao, Chen; Wang, Jin; Yin, Long; Yang, Jing; Jiang, Jian; Wan, Hongdan

    2014-10-01

    Internet Of Things (IOT) drives a significant increase in the extent and type of sensing technology and equipment. Sensors, instrumentation, control electronics, data logging and transmission units comprising such sensing systems will all require to be powered. Conventionally, electrical powering is supplied by batteries or/and electric power cables. The power supply by batteries usually has a limited lifetime, while the electric power cables are susceptible to electromagnetic interference. In fact, the electromagnetic interference is the key issue limiting the power supply in the strong electromagnetic radiation area and other extreme environments. The novel alternative method of power supply is power over fiber (PoF) technique. As fibers are used as power supply lines instead, the delivery of the power is inherently immune to electromagnetic radiation, and avoids cumbersome shielding of power lines. Such a safer power supply mode would be a promising candidate for applications in IOT. In this work, we built up optically powered active sensing system, supplying uninterrupted power for the remote active sensors and communication modules. Also, we proposed a novel maximum power point tracking technique for photovoltaic power convertors. In our system, the actual output efficiency greater than 40% within 1W laser power. After 1km fiber transmission and opto-electric power conversion, a stable electric power of 210mW was obtained, which is sufficient for operating an active sensing system.

  16. Adaptive intelligent power systems: Active distribution networks

    Electricity networks are extensive and well established. They form a key part of the infrastructure that supports industrialised society. These networks are moving from a period of stability to a time of potentially major transition, driven by a need for old equipment to be replaced, by government policy commitments to cleaner and renewable sources of electricity generation, and by change in the power industry. This paper looks at moves towards active distribution networks. The novel transmission and distribution systems of the future will challenge today's system designs. They will cope with variable voltages and frequencies, and will offer more flexible, sustainable options. Intelligent power networks will need innovation in several key areas of information technology. Active control of flexible, large-scale electrical power systems is required. Protection and control systems will have to react to faults and unusual transient behaviour and ensure recovery after such events. Real-time network simulation and performance analysis will be needed to provide decision support for system operators, and the inputs to energy and distribution management systems. Advanced sensors and measurement will be used to achieve higher degrees of network automation and better system control, while pervasive communications will allow networks to be reconfigured by intelligent systems

  17. Power Control Method for Research Reactor

    Baang, Dane; Suh, Yongsuk; Park, Cheol [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-05-15

    Considering safety-oriented design concept and other control environment, we developed a simple controller that provides limiting function of power change- rate as well as fine tracking performance. The design result has been well-proven via simulation and actual application to a TRIGA-II type research reactor. The proposed controller is designed to track the PDM(Power Demand) from operator input as long as maintaining the power change rate lower than a certain value for stable reactor operation. A power control method for a TRIGA-II type research reactor has been designed, simulated, and applied to actual reactor. The control performance during commissioning test shows that the proposed controller provides fine control performance for various changes in reference values (PDM), even though there is large measurement noise from neutron detectors. The overshoot at low power level is acceptable in a sense of reactor operation.

  18. DSP Control of Line Hybrid Active Filter

    Dan, Stan George; Benjamin, Doniga Daniel; Magureanu, R.;

    2005-01-01

    Active Power Filters have been intensively explored in the past decade. Hybrid active filters inherit the efficiency of passive filters and the improved performance of active filters, and thus constitute a viable improved approach for harmonic compensation. In this paper a parallel hybrid filter...... is studied for current harmonic compensation. The hybrid filter is formed by a single tuned Le filter and a small-rated power active filter, which are directly connected in series without any matching transformer. Thus the required rating of the active filter is much smaller than a conventional standalone...... active filter. Simulation and experimental results obtained in laboratory confirmed the validity and effectiveness of the control....

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

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

    2016-07-01

    In this paper is proposed a new balancing three-level three dimensional space vector modulation (B3L-3DSVM) strategy which uses a redundant voltage vectors to realize precise control and high-performance for a three phase three-level four-leg neutral point clamped (NPC) inverter based Shunt Active Power Filter (SAPF) for eliminate the source currents harmonics, reduce the magnitude of neutral wire current (eliminate the zero-sequence current produced by single-phase nonlinear loads), and to compensate the reactive power in the three-phase four-wire electrical networks. This strategy is proposed in order to gate switching pulses generation, dc bus voltage capacitors balancing (conserve equal voltage of the two dc bus capacitors), and to switching frequency reduced and fixed of inverter switches in same times. A Nonlinear Back Stepping Controllers (NBSC) are used for regulated the dc bus voltage capacitors and the SAPF injected currents to robustness, stabilizing the system and to improve the response and to eliminate the overshoot and undershoot of traditional PI (Proportional-Integral). Conventional three-level three dimensional space vector modulation (C3L-3DSVM) and B3L-3DSVM are calculated and compared in terms of error between the two dc bus voltage capacitors, SAPF output voltages and THDv, THDi of source currents, magnitude of source neutral wire current, and the reactive power compensation under unbalanced single phase nonlinear loads. The success, robustness, and the effectiveness of the proposed control strategies are demonstrated through simulation using Sim Power Systems and S-Function of MATLAB/SIMULINK. PMID:27018144

  20. Agent-based power sharing scheme for active hybrid power sources

    Jiang, Zhenhua

    The active hybridization technique provides an effective approach to combining the best properties of a heterogeneous set of power sources to achieve higher energy density, power density and fuel efficiency. Active hybrid power sources can be used to power hybrid electric vehicles with selected combinations of internal combustion engines, fuel cells, batteries, and/or supercapacitors. They can be deployed in all-electric ships to build a distributed electric power system. They can also be used in a bulk power system to construct an autonomous distributed energy system. An important aspect in designing an active hybrid power source is to find a suitable control strategy that can manage the active power sharing and take advantage of the inherent scalability and robustness benefits of the hybrid system. This paper presents an agent-based power sharing scheme for active hybrid power sources. To demonstrate the effectiveness of the proposed agent-based power sharing scheme, simulation studies are performed for a hybrid power source that can be used in a solar car as the main propulsion power module. Simulation results clearly indicate that the agent-based control framework is effective to coordinate the various energy sources and manage the power/voltage profiles.

  1. Control of Power Converters in AC Microgrids

    Rocabert, Joan; Luna, Alvaro; Blaabjerg, Frede; Rodriguez, Pedro

    2012-01-01

    electrical system. The high penetration of distributed generators, linked to the grid through highly controllable power processors based on power electronics, together with the incorporation of electrical energy storage systems, communication technologies, and controllable loads, opens new horizons to the...... effective expansion of microgrid applications integrated into electrical power systems. This paper carries out an overview about microgrid structures and control techniques at different hierarchical levels. At the power converter level, a detailed analysis of the main operation modes and control structures...... for power converters belonging to microgrids is carried out, focusing mainly on grid-forming, grid-feeding, and grid-supporting configurations. This analysis is extended as well toward the hierarchical control scheme of microgrids, which, based on the primary, secondary, and tertiary control layer...

  2. Laser welding closed-loop power control

    Bagger, Claus; Olsen, Flemming Ove

    2003-01-01

    A closed-loop control system is developed to maintain an even seam width on the root side of a laser weld by continually controlling the output laser power of a 1500 W CO2 laser.......A closed-loop control system is developed to maintain an even seam width on the root side of a laser weld by continually controlling the output laser power of a 1500 W CO2 laser....

  3. The Large Customer Reactive Power Control Possibilities

    Robert Małkowski; Zbigniew Szczerba

    2014-01-01

    In this paper the authors wish to draw attention to the rationale for, and the possibility of, the use of local reactive power sources by the Transmission Node Master Controller (TNMC). Large Customers (LC) are one of the possible reactive power sources. The paper presents the issues related to the need for coordination between the control systems installed in the LC network, and coordination between control systems of the LC as well as master control systems in the network.

  4. Technological tendencies for the development and implementation of fault tolerant active controls in combined cycle power plants; Tendencias tecnologicas para el desarrollo e implantacion de controles activos tolerantes a fallas en centrales de ciclo combinado

    Sanchez P, Marino; Verde R, Cristina [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)

    2006-07-01

    This document proposes a methodology that reunites support tools for the operator of a Combined Cycle Generating Power Station allowing him to identify and to classify gas turbine faults, it also reunites some tools for the generation of action advices in the decision making on the operation maneuvers necessary to counteract the effects caused by faults. We are talking about a system implemented in a power station with the reconfiguration of processes and fault arrangement capacities. For this purpose, the line of exhibition delimits first the existing knowledge on automatic control and operations supervision systems in a CCPP and immediately emphasizes the cracks of the system to let pass to the fault tolerant active control system that will detect faults of the gas and steam turbo-generators of a Combined Cycle Generating Power Plant. [Spanish] El presente documento propone una metodologia que reuna herramientas de ayuda al operador de una Central Generadora de Electricidad de Ciclo Combinado para permitirle la identificacion y clasificacion de fallas en las turbinas de gas, asi como herramientas para la generacion de consejos de accion en la toma de decisiones sobre las maniobras de operacion necesarias para contrarrestar los efectos provocados por fallas. Se trata principalmente de un sistema implantado en una central con las capacidades de re-configuracion de procesos y acomodo de fallas. Para esto, la linea de exposicion delimita primero el conocimiento existente sobre sistemas automaticos de control y supervision de operacion en una CGCC y resalta enseguida las grietas del sistema para darle paso al sistema de control activo tolerante a fallas que detectara fallas de los turbogeneradores de gas y vapor de una Central Generadora de Electricidad de Ciclo Combinado.

  5. Power Oscillation Damping Controller for Wind Power Plant Utilizing Wind Turbine Inertia as Energy Storage

    Knüppel, Thyge; Nielsen, Jørgen Nygård; Jensen, Kim Høj;

    2011-01-01

    utilizes the stored kinetic energy in the wind turbine (WT) mechanical system as energy storage from which damping power can be exchanged. This eliminates the need for curtailed active power production. Results are presented using modal analysis and induced torque coefficients (ITC) to depict the torques......For a wind power plant (WPP) the upper limit for active power output is bounded by the instantaneous wind conditions and therefore a WPP must curtail its power output when system services with active power are delivered. Here, a power oscillation damping controller (POD) for WPPs is presented that...... induced on the synchronous generators from the POD. These are supplemented with nonlinear time domain simulations with and without an auxiliary POD for the WPP. The work is based on a nonlinear, dynamic model of the 3.6 MW Siemens Wind Power wind turbine....

  6. Thermal power plant simulation and control

    Flynn, Damian

    2013-01-01

    Contributors of world-class excellence are brought together in Thermal Power Plant Simulation and Control to illustrate how current areas of research can be applied to power plant operation, leading to enhanced unit performance, asset management andplant competitiveness through intelligent monitoring and control strategies.

  7. Dynamic Reactive Power Control in Offshore HVDC Connected Wind Power Plants

    Sakamuri, Jayachandra N.; Cutululis, Nicolaos Antonio; Rather, Zakir Hussain; Rimez, Johan

    2016-01-01

    This paper presents a coordinated reactive power control for a HVDC connected cluster of offshore wind power plants (WPPs). The reactive power reference for the WPP cluster is estimated by an optimization algorithm aiming at minimum active power losses in the offshore AC Grid. For each optimal...... as wind turbine (WT) terminal, collector cable, and export cable, on the dynamic voltage profile of the offshore grid is investigated. Furthermore, the dynamic reactive power contribution from WTs from different WPPs of the cluster for such faults has also been studied....... reactive power set point, the OWPP cluster controller generates reactive power references for each WPP which further sends the AC voltage/ reactive power references to the associated WTs based on their available reactive power margin. The impact of faults at different locations in the offshore grid, such...

  8. Thyristor Controlled Reactor for Power Factor Improvement

    Sheila Mahapatra

    2014-04-01

    Full Text Available Power factor improvement is the essence of any power sector for reliable operation. This paper provides Thyristor Controlled Reactor regulated by programmed microcontroller which aids in improving power factor and retaining it close to unity under various loading conditions. The implementation is done on 8051 microcontrollerwhich isprogrammed using Keil software. To determine time lag between current and voltage PSpice softwareis used and to display power factor according tothe variation in loadProteus software is used. Whenever a capacitive load is connected to the transmission linea shunt reactor is connected which injects lagging reactive VARs to the power system. As a result the power factor is improved. The results given in this paper provides suitable microcontroller based reactive power compensation and power factor improvement technique using a Thyristor Controlled Reactor module.

  9. Real-Time Control of Active and Reactive Power for Doubly Fed Induction Generator (DFIG)-Based Wind Energy Conversion System

    Aman Abdulla Tanvir; Adel Merabet; Rachid Beguenane

    2015-01-01

    This paper presents the modeling, rapid control prototyping, and hardware-in-the-loop testing for real-time simulation and control of a grid-connected doubly fed induction generator (DFIG) in a laboratory-size wind turbine emulator for wind energy conversation systems. The generator is modeled using the direct-quadrature rotating reference frame circuit along with the aligned stator flux, and the field-oriented control approach is applied for independent control of the active and reactive pow...

  10. Development of nuclear power control technology

    The status on the development of nuclear power control(NPC) technology were reviewed. The advance of the fuzzy control and neural network(NN) control method for nuclear power plant was analyzed emphatically. The new trend of NPC technology advance was explored. The results of analysis reveal that the advancing tendency of NRC technology is developing from classical control to advanced control and intelligent control in the control method; the NPC technology is developing from simulated technology to digital (computer) technology and network technology in the hardware technology; the NPC system is progressing from single loop control to supervisory control, distributed computer control and control network-based in the the hierarchy of control system. In the NPC system, the PID method is still a most important control method, the fuzzy control method have good performance and the neural network method has great potential for the control of nuclear power plant. However, it is necessary to test and demonstrate for the application of neural network control to the nuclear power plant. (authors)

  11. Electric power distribution, automation, protection, and control

    Momoh, James A

    2007-01-01

    * Each Chapter Provides an Introduction, Illustrative Examples, and a SummaryIntroduction to Distribution Automation Systems Historical Background Distribution System Topology and Structure Distribution Automation (DA) and Control Computational Techniques for Distribution Systems Complex Power Concepts Balanced Voltage to Neutral-Connected System Power Relationship for f Y-?-Connected System Per-Unit System Calculation of Power Losses Voltage Regulation Techniques Voltage-Sag Analysis and Calculation Equipment Modeling Components Modeling Distribution System Line Model Distribution Power Flo

  12. Investigating power control in autonomous power systems with increasing wind power penetration

    Margaris, Ioannis D. [National Technical Univ. of Athens (Greece). Electric Energy Systems Lab.; Hansen, Anca D.; Sorensen, Poul [Risoe National Laboratory, Roskilde (Denmark). Wind Energy Dept.; Hatziargyriou, Nikos D. [National Technical Univ. of Athens (Greece). Electric Energy Systems Lab.; Public Power Corporation S.A., Athens (Greece)

    2009-07-01

    Increasing levels of wind penetration in autonomous power systems has set intensively high standards with respect to wind turbine technology during the last years. Special features of non-interconnected power systems make security issues rather critical, as the operation of large wind farms like conventional power plants is becoming a necessity. This paper includes the study case of Rhodos island, in Greece, where rapidly increasing wind penetration has started to impose serious security issues for the immediate future. The scenarios studied here correspond to reference year of study 2012 and include wind farms with three different wind turbine technologies - namely Doubly Fed Induction Generator (DFIG), Permanent Magnet Synchronous Generator (PMSG) and Active Stall Induction Generator (ASIG) based wind turbines. Aggregated models of the wind farms are being used and results for different load cases are being analyzed and discussed. The ability of wind farms to assist in some of the power system control services traditionally carried out by conventional synchronous generation is being investigated and discussed. The power grid of the island, including speed governors and automatic voltage regulators, is simulated in the dedicated power system simulation program Power Factory from DIgSILENT. (orig.)

  13. On load flow control in electric power systems

    Herbig, Arnim

    2000-01-01

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

  14. 基于优先顺序法的风电场限出力有功控制策略%Priority List-Based Output-Restricted Active Power Control Strategy for Wind Farms

    林俐; 谢永俊; 朱晨宸; 汪宁渤

    2013-01-01

    With the rapid increase of grid-integrated capacity of wind farms, wind farms should possess the adjusting ability of active power that can control active power output of wind farm according to the command from control center of power grid. Combining with actual requirement for active power control system of clustered wind farms in Jiuquan wind power base in Gansu province, China, taking the utilization of wind energy farthest and the prevention of frequent start/stop of wind power generators as the objectives and based on classical priority list method, an output-restricted active power control strategy for wind farms composed of variable speed constant frequency (VSCF) wind power generators is proposed. To meet the demand on output-restricted control for wind farms, an active power control frame in the level of wind farm and corresponding output-restricted control process are designed. Overall considering the prediction information, operating conditions and control characteristics of wind power generation units within wind farms, an output-restricted active power control sequence for wind farms, in which the indices of control performances of wind power generation units are taken as the index for rank ordering, is established, and then, based on the control sequence the method to allocate output-restricted active power is given. The correctness and effectiveness of the proposed control strategy are verified by the calculation of a wind farm composed of 33 doubly fed induction generators.%  随着风电并网容量的增加,风电场应具备有功功率调节能力,能根据电网调度部门指令控制其有功功率输出。结合甘肃酒泉风电基地集群风电有功控制系统的实际需要,以实现最大风能利用、避免风电场频繁起停为目标,基于经典优先顺序法提出了一种应用于变速恒频风电场的限出力有功控制策略。针对风电场限出力控制需要,设计了风电场层有功

  15. Modeling Control Situations in Power System Operations

    Saleem, Arshad; Lind, Morten; Singh, Sri Niwas

    2010-01-01

    Increased interconnection and loading of the power system along with deregulation has brought new challenges for electric power system operation, control and automation. Traditional power system models used in intelligent operation and control are highly dependent on the task purpose. Thus, a model...... for intelligent operation and control must represent system features, so that information from measurements can be related to possible system states and to control actions. These general modeling requirements are well understood, but it is, in general, difficult to translate them into a model because of the lack...... of explicit principles for model construction. This paper presents a work on using explicit means-ends model based reasoning about complex control situations which results in maintaining consistent perspectives and selecting appropriate control action for goal driven agents. An example of power system...

  16. Optimal control systems in hydro power plants

    The aim of the research done in this work is focused on obtaining the optimal models of hydro turbine including auxiliary equipment, analysis of governors for hydro power plants and analysis and design of optimal control laws that can be easily applicable in real hydro power plants. The methodology of the research and realization of the set goals consist of the following steps: scope of the models of hydro turbine, and their modification using experimental data; verification of analyzed models and comparison of advantages and disadvantages of analyzed models, with proposal of turbine model for design of control low; analysis of proportional-integral-derivative control with fixed parameters and gain scheduling and nonlinear control; analysis of dynamic characteristics of turbine model including control and comparison of parameters of simulated system with experimental data; design of optimal control of hydro power plant considering proposed cost function and verification of optimal control law with load rejection measured data. The hydro power plant models, including model of power grid are simulated in case of island ing and restoration after breakup and load rejection with consideration of real loading and unloading of hydro power plant. Finally, simulations provide optimal values of control parameters, stability boundaries and results easily applicable to real hydro power plants. (author)

  17. Modular supervisory controller for hybrid power systems

    Lemos Pereira, A. de

    2000-06-01

    The power supply of remote places has been commonly provided by thermal power plants, usually diesel generators. Although hybrid power systems may constitute the most economical solution in many applications their widespread application to the electrification schemes of remote areas still depends on improvements in the issues of design and operation control. The main limitations of the present hybrid power systems technology, which are identified in this work, are related to the control and supervision of the power system. Therefore this thesis focuses on the modularity of supervisory controllers in order to design cost-competitive and reliable hybrid power systems. The modular supervisory controller created in this project is considered an important part of a system design approach that aims to overcome the technical difficulties of the current engineering practice and contribute to open the market of hybrid power systems. The term modular refers to a set of design characteristics that allows the use of basically the same supervisory controller in different projects. The modularization and standardisation of the controller include several issues such as interfacing components, communication protocols, modelling, programming and control strategies. The modularity can reduce the highly specialised system engineering related to the integration of components, operation and control. It can also avoid the high costs for installation, service and maintenance. A modular algorithm for supervisory controllers has been developed (a Matlab program called SuperCon) using an object-oriented design and it has been tested through several simulations using different hybrid system configurations and different control strategies. This thesis presents a complete control system design process which can be used as the basis for the development and implementation of intelligent and autonomous supervisory controllers for hybrid power systems with modular characteristics. (au)

  18. Stability and control of wind farms in power systems

    Jauch, C.

    2006-10-15

    The Ph.D. project 'Stability and Control of Wind Farms in Power Systems' deals with some selected problems related to wind power in power systems. With increasing wind power penetration, wind turbines substitute the power production of conventional power plants. Therefore, wind turbines also have to take over the power system stabilisation and control tasks, that were traditionally carried out by conventional power plants. Out of the many aspects related to this problem, this project focuses on transient fault ride-through and power system stabilisation. The selection of turbine types considered in this project is limited to active-stall turbines and variable speed, variable pitch turbines with gearboxes and full-scale converter-connected synchronous generators. As a basis for the project, a study into the state of the art is conducted at the beginning of the project. Grid connection requirements that were in force, or published as drafts, at the time, and scientific literature related to the topic, are studied. The project is based on simulations of wind turbines in a power system simulations tool. Some of the models used in this project were readily available prior to the project; the development of others is part of the project. The most extensive modelling work deals with the design of the electrical part of the variable speed turbine and its controls. To simulate realistic grid operation the wind turbine models are connected to an aggregated model of the Nordic power system. For that purpose the Nordic power system model, which was available prior to the project, is extended with a realistic feeder configuration. It is commonly demanded from modern wind turbines, that they must not disconnect in case of transient faults. Therefore, controllers are designed that enable the two turbine types to ride through transient faults. With these transient fault controllers the wind turbines can stay connected to the grid, such that their generation capacity is

  19. Application of H∞ control theory to PWR power control

    In this paper, a robust controller is designed by the use of H∞ control theory for the PWR power control. The design specification is incorporated by the frequency weights using the mixed-sensitivity problem. The robustness of H∞ control is verified by comparing with the classical output feedback control and LQG control in the case of measurement delay of the power measurement system. The H∞ optimal control shows excellent stability-robustness and performance-robustness for external disturbances and noises, model parameter variations, and modeling errors. It also provides a practical design method because the design specification can be easily implemented

  20. reactor power control using fuzzy logic

    power stabilization is a critical issue in nuclear reactors. convention pd- controller is currently used in egypt second testing research reactor (ETRR-2). two fuzzy controllers are proposed to control the reactor power of ETRR-2 reactor. the design of the first one is based on a set of linguistic rules that were adopted from the human operators experience. after off-line fuzzy computations, the controller is a lookup table, and thus, real time controller is achieved. comparing this f lc response with the pd-controller response, which already exists in the system, through studying the expected transients during the normal operation of ETRR-2 reactor, the simulation results show that, fl s has the better response, the second controller is adaptive fuzzy controller, which is proposed to deal with system non-linearity . The simulation results show that the proposed adaptive fuzzy controller gives a better integral square error (i se) index than the existing conventional od controller

  1. Control System for Electromagnet Power Supplies

    Ermolov, E. Y.; Kozak, V. R.; Kuper, E. A.; Medvedko, A. S.; Petrov, S. P.; Veremeenko, V. F.

    2001-01-01

    A set of power supplies (PS) with output power rated from 100 W up to 10 kW for electromagnets powering was developed. These PS have range of current tuning of 60-80 db with high accuracy (error should be less than 0,01%). Some types of power supplies have bipolar output current. The report will describe a set of unified embedded devices for control and measurements of PS incorporated into distributed control systems. These embedded devices includes DAC, ADC with multiplexers and status Input...

  2. Active control of radiated sound using nearfield pressure sensing

    CHEN Ke'an; YIN Xuefei

    2004-01-01

    Based on nearfield sound pressure sensing to pick up error information, an approach for constructing active acoustic structure to effectively reduce radiated sound power at low frequency is proposed. The idea is that a nearfield pressure after active control is used as error signals and transformed into an objective function in adaptive active control process.Firstly sound power expression using near-field pressure radiated from a flexible structure is derived, and then three kind of nearfield pressure based active control strategies, I.e. Minimization of radiated sound power, minimization of sound power for dominant radiation modes and minimization of sound power for modified dominant radiation modes are respectively presented and applied to active control of radiated single and broadband noise. Finally computer simulations on sound power reduction under three strategies are conducted and it is shown that the proposed active control strategies are invalid and considerable reduction in radiated sound power can be achieved.

  3. The SSRF power supply control system

    The SSRF power supply control system is a fully distributed control system based on the EPICS system. About 65K runtime database records run in the 27 VME/IOC controllers to make physics access more than 600 sets of power' supplies distributed in the SSRF facility. In this paper, the layered system architecture and its working principles are introduced. The EPICS-based control solutions for the PSI-designed and SINAP-designed digital controllers are described. The hardware and software, together with the communication technology applied in the system, are presented. (authors)

  4. Selective harmonic control for power converters

    Zhou, Keliang; Yang, Yongheng; Blaabjerg, Frede; Lu, Wenzhou; Danwei, Wang

    This paper proposes an Internal Model Principle (IMP) based Selective Harmonic Controller (SHC) for power converters. The proposed SHC offers an optimal control solution for power converters to mitigate power harmonics. It makes a good trade-off among cost, complexity and performance. It has high...... accuracy and fast transient response, and it is cost-effective, easy for real-time implementation, and compatible for design rules-of-thumb. An application on a three-phase PWM converter has confirmed the effectiveness of the proposed control scheme in terms of harmonic mitigation....

  5. Hydraulically powered dissimilar teleoperated system controller design

    This paper will address two issues associated with the implementation of a hydraulically powered dissimilar master-slave teleoperated system. These issues are the overall system control architecture and the design of robust hydraulic servo controllers for the position control problem. Finally, a discussion of overall system performance on an actual teleoperated system will be presented

  6. Power grid control in retreat

    Bilateral grid control that obstructs free trade of electricity is in retreat. Negotiations on opening the Skagerrak cables are in progress. The EU, national authorities, network companies with system responsibility, market actors, electricity exchanges all push for quick opening of the grid. At present, free trade of electricity is hindered not so much by physical bottlenecks in the grid as by market actors possessing control and bilateral agreements. The article discusses current bilateral agreements and how they might affect the possibility of a free trade of electricity in Europe

  7. Power flow analysis of a power system in the presence of interline power flow controller (IPFC)

    T. Ramana; Ch. Padmanabharaju; S.Sivanagaraju; A. V. Naresh Babu

    2010-01-01

    One of the latest generation flexible AC transmission systems (FACTS) controllers is interline power flow controller (IPFC). In general, it is connected in multiple transmission lines of a power system network. This paper presents power injection model (PIM) of IPFC. This model is incorporated in Newton-Raphson (NR) power flow algorithm to study the effect of IPFC parameters in power flow analysis. A program in MATLAB has been written in order to extend conventional NR algorithm based on this...

  8. Power electronic converters modeling and control with case studies

    Bacha, Seddik; Bratcu, Antoneta Iuliana

    2014-01-01

    Modern power electronic converters are involved in a very broad spectrum of applications: switched-mode power supplies, electrical-machine-motion-control, active power filters, distributed power generation, flexible AC transmission systems, renewable energy conversion systems and vehicular technology, among them. Power Electronics Converters Modeling and Control teaches the reader how to analyze and model the behavior of converters and so to improve their design and control. Dealing with a set of confirmed algorithms specifically developed for use with power converters, this text is in two parts: models and control methods. The first is a detailed exposition of the most usual power converter models: ·        switched and averaged models; ·        small/large-signal models; and ·        time/frequency models. The second focuses on three groups of control methods: ·        linear control approaches normally associated with power converters; ·        resonant controllers b...

  9. Optimal control applications in electric power systems

    Christensen, G S; Soliman, S A

    1987-01-01

    Significant advances in the field of optimal control have been made over the past few decades. These advances have been well documented in numerous fine publications, and have motivated a number of innovations in electric power system engineering, but they have not yet been collected in book form. Our purpose in writing this book is to provide a description of some of the applications of optimal control techniques to practical power system problems. The book is designed for advanced undergraduate courses in electric power systems, as well as graduate courses in electrical engineering, applied mathematics, and industrial engineering. It is also intended as a self-study aid for practicing personnel involved in the planning and operation of electric power systems for utilities, manufacturers, and consulting and government regulatory agencies. The book consists of seven chapters. It begins with an introductory chapter that briefly reviews the history of optimal control and its power system applications and also p...

  10. Nuclear power plant control system

    Purpose: To effectively transfer the operation of a nuclear power plant including a bwr type reactor to single load operation in the station with no increase in the neutron flux and water level in the reactor by the combined use of recycle pump trip and feedwater pump trip. Method: Upon rapid load decrease in a turbine generator, at least one of usually operated feedwater pumps and a recycle pump are tripped and the starting for a stand-by feedwater pump is inhibited. This rapidly decreases the recycling flow rate to thereby lower the neutron flux before generation of pressure increase and also decreases the feedwater flow rate to thereby suppress the increase in the water level due to increase in voids, whereby the operation is smoothly transferred to the single load operation in the station. (Horiuchi, T.)

  11. Performance and Analysis of Reactive Power Compensation by Unified Power Flow Controller

    Yogita Kumari

    2015-09-01

    Full Text Available The Unified Power Flow Controller (UPFC is the most versatile of the FACTS controllers envisaged so far. The main function of the UPFC is to control the flow of real and reactive power by injection of a voltage in series with the transmission line. Both the magnitude and the phase angle of the voltage can be varied independently. Real and Reactive power flow control can allow for power flow in prescribed routes, loading of transmission lines close to their thermal limits and can be utilized for improving transient and small signal stability of the power system. In this paper UPFC is incorporated in a SMIB (Single Machine Infinite Bus system and the response of SMIB system has been recorded with and without UPFC, thereafter the comparison of both the output has been done. When no UPFC is installed, real and reactive power through the transmission line cannot be controlled. This paper presents control and performance of UPFC intended for installation on that transmission line to control power flow. Installing the UPFC makes it possible to control amount of active power flowing through the line. Simulations are carried out using MATLAB software to validate the performance of the UPFC.

  12. Phase Detector for Power-Factor Controller

    Nola, F. J.

    1984-01-01

    Positive feedback assures reliable switching. Three Phase Power Factor Controller includes three phase detectors, each produces rectangular waves of duration approximately equal to lag time between line voltage and motor current.

  13. Controlled Compact High Voltage Power Lines

    Postolati V.

    2016-04-01

    Full Text Available Nowadays modern overhead transmission lines (OHL constructions having several significant differences from conventional ones are being used in power grids more and more widely. Implementation of compact overhead lines equipped with FACTS devices, including phase angle regulator settings (compact controlled OHL, appears to be one of the most effective ways of power grid development. Compact controlled AC HV OHL represent a new generation of power transmission lines embodying recent advanced achievements in design solutions, including towers and insulation, together with interconnection schemes and control systems. Results of comprehensive research and development in relation to 110–500kV compact controlled power transmission lines together with theoretical basis, substantiation, and methodological approaches to their practical application are presented in the present paper.

  14. Microgrid Control Techniques at Power Converter Level

    Valouch, Viktor; Šimek, Petr; Škramlík, Jiří; Tlustý, J.

    Ostrava: VŠB - TU Ostrava, 2013, s. 611-616. ISBN 978-80-248-2988-3. [Electric Power Engineering - EPE 2013. Kouty nad Desnou (CZ), 28.05.2013-30.05.2013] Institutional support: RVO:61388998 Keywords : microgrid * power converter * droop control Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering

  15. Hybrid wind power balance control strategy using thermal power, hydro power and flow batteries

    Gelazanskas, Linas; Baranauskas, Audrius; Gamage, Kelum; Azubalis, Mindaugas

    2016-01-01

    The increased number of renewable power plants pose threat to power system balance. Their intermittent nature makes it very difficult to predict power output, thus either additional reserve power plants or new storage and control technologies are required. Traditional spinning reserve cannot fully compensate sudden changes in renewable energy power generation. Using new storage technologies such as flow batteries, it is feasible to balance the variations in power and voltage within very short...

  16. Remotely powered and controlled EAPap actuator by amplitude modulated microwaves

    This paper reports on a remotely powered and controlled Electro-Active Paper (EAPap) actuator without onboard controller using amplitude modulated microwaves. A rectenna is a key element for microwave power transmission that converts microwaves into dc power through coupling and rectification. In this study, the concept of a remotely controlled and powered EAPap actuator is proposed by means of modulating microwaves with a control signal and demodulating it through the rectenna rectification. This concept is applied to a robust EAPap actuator, namely cellulose–polypyrrole–ionic liquid (CPIL) EAPap. Details of fabrication and characterization of the rectenna and the CPIL-EAPap actuator are explained. Also, the charge accumulation problem of the actuator is explained and resolved by connecting an additional resistor. Since this idea can eliminate the onboard controller by supplying the operating signal through modulation, a compact and lightweight actuator can be achieved, which is useful for biomimetic robots and remotely driven actuators. (technical note)

  17. Power system dynamics stability and control

    Padiyar, K R

    2008-01-01

    Modern power systems tend to be very Complex not only due to increasing Demand for quality power, but also on Account of extensive interconnections and increasing dependence on control for optimum utilization for existing resources. A good Knowledge of system dynamics and control is Essential for secure operation of the system. This book is intended to serve the needs of the Student and practicing engineers. A Large number of illustrative examples are included to provide an insight into the application of the theory.

  18. Facts controllers in power transmission and distribution

    Padiyar, KR

    2007-01-01

    About the Book: The emerging technology of Flexible AC Transmission System (FACTS) enables planning and operation of power systems at minimum costs, without compromising security. This is based on modern high power electronic systems that provide fast controllability to ensure ''flexible'' operation under changing system conditions. This book presents a comprehensive treatment of the subject by discussing the operating principles, mathematical models, control design and issues that affect the applications. The concepts are explained often with illustrative examples and case studies. In partic

  19. Overview on the power supply systems for plasma instabilities control

    Toigo, V., E-mail: vanni.toigo@igi.cnr.it [Consorzio RFX - EURATOM - ENEA Association, C.so Stati Uniti 4, 35127 Padova (Italy); Gaio, E.; Piovan, R.; Barp, M.; Bigi, M.; Ferro, A.; Finotti, C.; Novello, L.; Recchia, M.; Zamengo, A.; Zanotto, L. [Consorzio RFX - EURATOM - ENEA Association, C.so Stati Uniti 4, 35127 Padova (Italy)

    2011-10-15

    The paper presents an overview on the power supply (PS) systems for plasma instabilities control in fusion experiments, based on active control coils. First, the MHD instabilities and the approach to their control in Tokamaks and Reversed Field Pinches (RFPs) are described. Then, the features of MHD modes controls presently used in fusion experiments are reviewed. For the control systems based on active coils fed by fast power supplies, the typical requirements in terms of power, dynamics, accuracy and delay are summarized and discussed. Then, a survey on the technology available to design these types of PSs is given, together with the most suitable circuit topologies and guidelines for the design, on the basis of solutions adopted in existing experiments.

  20. Adaptive Compensation of Reactive Power With Shunt Active Power Filters

    Blaabjerg, Frede; Asiminoaei, Lucian; Hansen, Steffan;

    2008-01-01

    This paper describes an adaptive method for compensating the reactive power with an active power filter (APF), which is initially rated for mitigation of only the harmonic currents given by a nonlinear industrial load. It is proven that, if the harmonic currents do not load the APF at the rated...

  1. Robust Decentralized Control of Unified Power Flow Controller

    Hossein Shayeghi

    2009-01-01

    Full Text Available A new approach based on structured singular value is proposed for the robust decentralized Unified Power Flow Controller (UPFC design. To achieve decentralization, using the schauder fixed point theorem the synthesis and analysis of Multi-Input Multi-output (MIMO control system is translated into set of equivalent Multi-Input Single-Output (MISO control system. Power systems such as the other industrial plants contain different kinds of uncertainties, which should be considered in controller design procedure. For this reason, the idea of µ-synthesis technique was used for designing of UPFC controllers. The proposed µ-based controller has a decentralized scheme and advantage of a decentralized controller design is reduction in the controller complexity and suitability for practical implementation. The effectiveness of the proposed control strategy was evaluated under operating conditions for damping low frequency oscillations in comparison with the classical controller to demonstrate its robust performance through nonlinear time simulation and some performance indices.

  2. Voluntary muscle activation improves with power training and is associated with changes in gait speed in mobility-limited older adults - A randomized controlled trial.

    Hvid, Lars G; Strotmeyer, Elsa S; Skjødt, Mathias; Magnussen, Line V; Andersen, Marianne; Caserotti, Paolo

    2016-07-01

    Incomplete voluntary muscle activation may contribute to impaired muscle mechanical function and physical function in older adults. Exercise interventions have been shown to increase voluntary muscle activation, although the evidence is sparse for mobility-limited older adults, particularly in association with physical function. This study examined the effects of 12weeks of power training on outcomes of voluntary muscle activation and gait speed in mobility-limited older adults from the Healthy Ageing Network of Competence (HANC) study. We included 37 older men and women with a usual gait speed of changes (TG vs. CG; pchange in muscle thickness was non-significant (+0.08cm). Improvements in voluntary muscle activation were associated with improvements in gait speed in TG (r=0.67, pmobility-limited older adults following 12-weeks of progressive power training, and is associated with improved maximal gait speed. Incomplete voluntary muscle activation should be considered one of the key mechanisms influencing muscle mechanical function and gait speed in older adults. PMID:27090485

  3. Power flow control of intertied ac microgrids

    Nutkani, Inam Ullah; Loh, Poh Chiang; Blaabjerg, Frede

    2013-01-01

    interlinking power converters. Active and reactive power flows of these converters should preferably be managed autonomously without demanding for fast communication links. A scheme that can fulfill the objectives is now proposed, which upon realised, will result in more robustly integrated microgrids with...

  4. Adaptive control of active filter using DSP

    In order to reduce output-voltage ripple of power supply, an active filter is necessary. In this paper, the active filter with DSP is proposed. The waveform from active filter can be flexibly improved by DSP programming. The output-voltage ripple can be enough reduced by mixing frequency components of the input-voltage ripple. The result of adaptive control using LMS algorism is presented. The improvement by using filtered-X method is discussed. (author)

  5. 基于无差拍控制的有源电力滤波器直接电流控制研究%Research on Direct Current Control of Active Power Filter Based on Deadbeat Control

    贺永平; 庄圣贤

    2015-01-01

    An improved method for direct current control of active power filter based on deadbeat control is proposed. Compared with the traditional current control method, the deadbeat control is carried out in the αβ coordinate system to avoid the serious coupling by dq transform. Fundamental component of load current is brought into the given value of source current, the system dynamic response is enhanced. The load current and the source voltage are feed-forward compensated to improve the compensation precision of the system. The simulation results show that the improved method has better dynamic performance than the conventional control method and also it can realize the selective compensation of load current between harmonics and reactive component.%提出一种基于无差拍控制的有源电力滤波器网侧电流直接控制方法。与传统网侧电流控制法相比,该方法的无差拍电流控制策略在αβ坐标系中实现,抑制了由dq变换引入的严重耦合;引入负载电流基波分量作为网侧电流的给定值,增强了系统的动态响应;对负载电流和电网电压进行前馈补偿,进一步提高了系统的补偿精度。仿真结果表明:改进方法比传统控制法具有更优越的动态性能,且可以实现APF对负载电流谐波分量和无功分量的选择性补偿。

  6. Comparison of Power Control Strategies for DFIG Wind Turbines

    Teodorescu, Remus; Luna, A.; Rodríguez, P.;

    2008-01-01

    The classical control techniques for regulating the active and reactive power delivery in doubly fed induction generators (DFIG), for wind power applications, are normally based on voltage oriented control (VOC) strategies. Among these algorithms, those that work in a synchronous reference frame...... VOC strategy able to control the operation of a DFIG in the αβ reference frame, with no need of flux position estimation, something that conducts to a more simple and robust algorithm. In order to evaluate the advantages of this new control proposal, namely VOC-RRF, their performance will be compared...

  7. Smart — STATCOM control strategy implementation in wind power plants

    Sintamarean, Nicolae Christian; Cantarellas, Antoni Mir; Miranda, H.;

    2012-01-01

    converters is increasing. This paper deals with an advanced control strategy design of a three-level converter performing STATCOM and Active Filter functionalities. The proposed system is called Smart-STATCOM since it has the capability of self-controlling reactive power and harmonic voltages at the same...... the wind farm and also to provide grid support, as it is required by the grid codes. One of the main compliance difficulties that can be found in such power plants are related to reactive power compensation and to keep the harmonics content between the allowed limits, even if the power of the WPP...... time. Therefore, deciding the amount of non-active currents (fundamental, 5th and 7th harmonics) to be injected depending on the PCC voltage quality. Experimental results of the proposed control strategy are analyzed in order to validate the performance of the entire system....

  8. Modelling supervisory controller for hybrid power systems

    Pereira, A.; Bindner, H.; Lundsager, P. [Risoe National Lab., Roskilde (Denmark); Jannerup, O. [Technical Univ. of Denmark, Dept. of Automation, Lyngby (Denmark)

    1999-03-01

    Supervisory controllers are important to achieve optimal operation of hybrid power systems. The performance and economics of such systems depend mainly on the control strategy for switching on/off components. The modular concept described in this paper is an attempt to design standard supervisory controllers that could be used in different applications, such as village power and telecommunication applications. This paper presents some basic aspects of modelling and design of modular supervisory controllers using the object-oriented modelling technique. The functional abstraction hierarchy technique is used to formulate the control requirements and identify the functions of the control system. The modular algorithm is generic and flexible enough to be used with any system configuration and several goals (different applications). The modularity includes accepting modification of system configuration and goals during operation with minor or no changes in the supervisory controller. (au)

  9. Fractional Power Control for Decentralized Wireless Networks

    Jindal, Nihar; Andrews, Jeffrey G

    2007-01-01

    We propose and analyze a new paradigm for power control in decentralized wireless networks, termed fractional power control. Transmission power is chosen as the current channel quality raised to an exponent -s, where s is a constant between 0 and 1. Choosing s = 1 and s = 0 correspond to the familiar cases of channel inversion and constant power transmission, respectively. Choosing s in (0, 1) allows all intermediate policies between these two extremes to be evaluated, and we see that neither extreme is ideal. We prove that using an exponent of s = 1/2 optimizes the transmission capacity of an ad hoc network, meaning that the inverse square root of the channel strength is the optimal transmit power scaling. Intuitively, this choice achieves the optimal balance between helping disadvantaged users while making sure they do not flood the network with interference.

  10. Efficiency in Controlling Activities

    Van Nguyen, Tuyen

    2015-01-01

    Controlling is essential for financial success of corporations. An efficient controlling system should be implemented in order to manage financial performance from income, expense to profitability. The purpose of the thesis is to provide insight knowledge towards corporate accounting management as well as to propose potential improvement for the existing controlling system of the case company, which is Bosch Rexroth Japan. The theoretical framework creates the knowledge foundation for re...

  11. Coordinated control of wind power and energy storage

    Zhao, Haoran

    in many aspects, such as reliability, power quality and stability. With the rapid development of energy storage technology, the application of Energy Storage System (ESS) is considered as an effective solution to handle the aforementioned challenges. The main objective of this study is to investigate......) of a small variable speed Wind Energy Conversion System (WECS) is developed. It showed good tracking performance towards the optimum Tip Speed Ratio (TSR) and robustness with fast adaptation to uncertainties and disturbances. For the wind farm control, the optimal active power control based on......Nowadays, wind power has become one of the fastest growing sources of electricity in the world. Due to the inherent variability and uncertainty, wind power integration into the grid brings challenges for power systems, particularly when the wind power penetration level is high. The challenges exist...

  12. Motion Control of Urea-Powered Biocompatible Hollow Microcapsules.

    Ma, Xing; Wang, Xu; Hahn, Kersten; Sánchez, Samuel

    2016-03-22

    The quest for biocompatible microswimmers powered by compatible fuel and with full motion control over their self-propulsion is a long-standing challenge in the field of active matter and microrobotics. Here, we present an active hybrid microcapsule motor based on Janus hollow mesoporous silica microparticles powered by the biocatalytic decomposition of urea at physiological concentrations. The directional self-propelled motion lasts longer than 10 min with an average velocity of up to 5 body lengths per second. Additionally, we control the velocity of the micromotor by chemically inhibiting and reactivating the enzymatic activity of urease. The incorporation of magnetic material within the Janus structure provides remote magnetic control on the movement direction. Furthermore, the mesoporous/hollow structure can load both small molecules and larger particles up to hundreds of nanometers, making the hybrid micromotor an active and controllable drug delivery microsystem. PMID:26863183

  13. The ELETTRA power supply control system

    The control of the magnet power supplies is one of the most important tasks within the ELETTRA control system. The equipment interface units (EIU) have been integrated in the power supply cabinets, providing local and remote control functions. Each EIU consists of a VMEbus based crate containing the digital-to-analog converter (DAC), analog-to-digital converter (ADC), digital input/output modules together with a microprocessor module. Exploiting the same communication interface, an integrated development system has been implemented which has been used for the tests of the embedded EIUs. The detailed EIU hardware and software design is given. (author) 8 refs.; 2 figs.; 1 tab

  14. Experimental development of power reactor intelligent control

    The US nuclear utility industry initiated an ambitious program to modernize the control systems at a minimum of ten existing nuclear power plants by the year 2000. That program addresses urgent needs to replace obsolete instrumentation and analog controls with highly reliable state-of-the-art computer-based digital systems. Large increases in functionality that could theoretically be achieved in a distributed digital control system are not an initial priority in the industry program but could be logically considered in later phases. This paper discusses the initial development of an experimental sequence for developing, testing, and verifying intelligent fault-accommodating control for commercial nuclear power plant application. The sequence includes an ultra-safe university research reactor (TRIGA) and a passively safe experimental power plant (Experimental Breeder Reactor 2)

  15. The reactor power control system based on digital control in nuclear power plant

    The PLC (Programmable Logical Controller), digital communication and redundant techniques are applied in the rod control and position indication system(namely the reactor power control system) to perform the power control in the 300 MW reactor automatically and integrally in Qinshan Phase I project. This paper introduces the features, digital design methods of hardware of the instrumentation and control system (I and C) in the reactor power control. It is more convenient for the information exchange by human-machine interface (HMI), operation and maintenance, and the system reliability has been greatly improved after the project being reconstructed. (authors)

  16. Optimal coordinated voltage control of power systems

    LI Yan-jun; HILL David J.; WU Tie-jun

    2006-01-01

    An immune algorithm solution is proposed in this paper to deal with the problem of optimal coordination of local physically based controllers in order to preserve or retain mid and long term voltage stability. This problem is in fact a global coordination control problem which involves not only sequencing and timing different control devices but also tuning the parameters of controllers. A multi-stage coordinated control scheme is presented, aiming at retaining good voltage levels with minimal control efforts and costs after severe disturbances in power systems. A self-pattern-recognized vaccination procedure is developed to transfer effective heuristic information into the new generation of solution candidates to speed up the convergence of the search procedure to global optima. An example of four bus power system case study is investigated to show the effectiveness and efficiency of the proposed algorithm, compared with several existing approaches such as differential dynamic programming and tree-search.

  17. Reasoning about Control Situations in Power Systems

    Saleem, Arshad; Lind, Morten

    Introduction of distributed generation, deregulation and distribution of control has brought new challenges for electric power system operation, control and automation. Traditional power system models used in reasoning tasks such as intelligent control are highly dependent on the task purpose. Thus......, a model for intelligent control must represent system features, so that information from measurements can be related to possible system states and to control actions. These general modeling requirements are well understood, but it is, in general, difficult to translate them into a model because of...... the lack of explicit principles for model construction. Available modeling concepts for intelligent control do not assist the model builder in the selection of model content i.e. in deciding what is relevant to represent for a particular reasoning task and thereby faced with a difficult interpretation...

  18. Controllability of (max,+) formal power series

    Komenda, Jan; Lahaye, S.; Boimond, J.-L.

    Bari: The International Federation of Automatic Control, 2009 - (Fanti, M.; Dotoli, M.), s. 97-102 ISBN 978-3-902661-44-9. [2nd IFAC Workshop on Dependable Control of Discrete Systems. Bari (IT), 10.06.2009-12.06.2009] Grant ostatní: EU Projekt(XE) EU. ICT .DISC 224498 Institutional research plan: CEZ:AV0Z10190503 Keywords : controllability * (max,+) automata * (max,+) formal power series * Hadamard product Subject RIV: BA - General Mathematics

  19. Trends in active power line conditioners

    Akagi, Hirofumi (Okayama Univ. (Japan). Dept. of Electrical Engineering)

    1994-05-01

    Active power line conditioners, which are classified into shunt and series ones, have been studied with the focus on their practical installation in industrial power systems. In 1986, a combined system of a shunt active conditioner of rating 900 kVA and a shunt passive filter of rating 6,600 kVA was practically installed to suppress the harmonics produced by a large capacity cycloconverter for steel mill drives. More than one hundred shunt active conditioners have been operating properly in Japan. The largest one is 10 mVA, which was developed for flicker compensation for an arc furnace with the help of a shunt passive filter of 20 mVA. In this paper, the term of ''active power line conditioners'' would be used instead of that of ''active power filters'' because active power line conditioners would cover a wider sense than active power filters. The primary intent of this paper is to present trends in active power line conditioners using PWM inverters, paying attention to practical applications.

  20. Active control of convection

    Bau, H.H. [Univ. of Pennsylvania, Philadelphia, PA (United States)

    1995-12-31

    Using stability theory, numerical simulations, and in some instances experiments, it is demonstrated that the critical Rayleigh number for the bifurcation (1) from the no-motion (conduction) state to the motion state and (2) from time-independent convection to time-dependent, oscillatory convection in the thermal convection loop and Rayleigh-Benard problems can be significantly increased or decreased. This is accomplished through the use of a feedback controller effectuating small perturbations in the boundary data. The controller consists of sensors which detect deviations in the fluid`s temperature from the motionless, conductive values and then direct actuators to respond to these deviations in such a way as to suppress the naturally occurring flow instabilities. Actuators which modify the boundary`s temperature/heat flux are considered. The feedback controller can also be used to control flow patterns and generate complex dynamic behavior at relatively low Rayleigh numbers.

  1. Active Combustion Control Valve Project

    National Aeronautics and Space Administration — Over the past decade, research into active combustion control has yielded impressive results in suppressing thermoacoustic instabilities and widening the...

  2. Intelligent distributed control for nuclear power plants

    This project was initiated in September 1989 as a three year project to develop and demonstrate Intelligent Distributed Control (IDC) for Nuclear Power Plants. The body of this Third Annual Technical Progress report summarizes the period from September 1991 to October 1992. There were two primary goals of this research project. The first goal was to combine diagnostics and control to achieve a highly automated power plant as described by M.A. Schultz. His philosophy, is to improve public perception of the safety of nuclear power plants by incorporating a high degree of automation where a greatly simplified operator control console minimizes the possibility of human error in power plant operations. To achieve this goal, a hierarchically distributed control system with automated responses to plant upset conditions was pursued in this research. The second goal was to apply this research to develop a prototype demonstration on an actual power plant system, the EBR-2 stem plant. Emphasized in this Third Annual Technical Progress Report is the continuing development of the in-plant intelligent control demonstration for the final project milestone and includes: simulation validation and the initial approach to experiment formulation

  3. Instantaneous Active and Reactive Power Measuring Method in Three Phase Power System

    A. TAHRI

    2005-01-01

    Full Text Available This paper describes an electronic means of measuring the instantaneous active and reactive power absorbed by any electrical equipment. The measurements are based on the Clark (a-b and Park (d-q transformations. The system is useful to teach electrical machines in Park’s coordinates and it allows also the study and control of some power electronics converters that are connected to three phase power network, such as static VAR compensator. The principle of the measuring method of the active and reactive power is described, and analyzed for different tests. The effectiveness of the proposed measuring method is confirmed by experimental investigation employing a test system.

  4. Regulatory control of nuclear power plants

    The purpose of this book is to support IAEA training courses and workshops in the field of regulatory control of nuclear power plants as well as to support the regulatory bodies of Member States in their own training activities. The target group is the professional staff members of nuclear safety regulatory bodies supervising nuclear power plants and having duties and responsibilities in the following regulatory fields: regulatory framework; regulatory organization; regulatory guidance; licensing and licensing documents; assessment of safety; and regulatory inspection and enforcement. Important topics such as regulatory competence and quality of regulatory work as well as emergency preparedness and public communication are also covered. The book also presents the key issues of nuclear safety such as 'defence-in-depth' and safety culture and explains how these should be taken into account in regulatory work, e.g. during safety assessment and regulatory inspection. The book also reflects how nuclear safety has been developed during the years on the basis of operating experience feedback and results of safety research by giving topical examples. The examples cover development of operating procedures and accident management to cope with complicated incidents and severe accidents to stress the importance of regulatory role in nuclear safety research. The main target group is new staff members of regulatory bodies, but the book also offers good examples for more experienced inspectors to be used as comparison and discussion basis in internal workshops organized by the regulatory bodies for refreshing and continuing training. The book was originally compiled on the basis of presentations provided during the two regulatory control training courses in 1997 and 1998. The textbook was reviewed at the beginning of the years 2000 and 2002 by IAEA staff members and consistency with the latest revisions of safety standards have been ensured. The textbook was completed in the

  5. Survey of wind farm control - power and fatigue optimization

    Knudsen, Torben; Bak, Thomas; Svenstrup, Mikael

    2015-01-01

    The main goal of this paper is to establish the present state of the art for wind farm control. The control area that will be focused on is the mechanical/aerodynamic part, which includes the wind turbines, their power production, fatigue and wakes affecting neighbouring wind turbines. The sub......-objectives in this area of research are as follows: (i) maximizing the total wind farm power production; (ii) following a reference for the total wind farm active power; and (iii) doing this in a manner that minimizes fatigue loading for the wind turbines in the farm. Each of these sub-objectives is discussed......, including the following important control issues: choice of input and output, control method and modelling used for controller design and simulation. The available literature from industry is also considered. Finally, a conclusion is presented discussing the established results, open challenges and...

  6. Predictive Smart Grid Control with Exact Aggregated Power Constraints

    Trangbæk, K; Petersen, Mette Højgaard; Bendtsen, Jan Dimon;

    2012-01-01

    This chapter deals with hierarchical model predictive control (MPC) of smart grid systems. The design consists of a high-level MPC controller, a second level of so-called aggregators,which reduces the computational and communication related load on the high-level control, and a lower level of...... autonomous consumers. The control system is tasked with balancing electric power production and consumption within the smart grid, and makes active use of the flexibility of a large number of power producing and/or power consuming units. The load variations on the grid arise on one hand from varying...... simulation of a smart grid containing consumers with very different characteristics. It is demonstrated how the novel aggregation method makes it possible for the top level controller to treat all these as one big consumer, significantly simplifying the optimisation....

  7. Power-based control of physical systems

    Garcia-Canseco, Eloisa; Jeltsema, Dimitri; Ortega, Romeo; Scherpen, Jacquelien M. A.

    2010-01-01

    It is well known that energy-balancing control is stymied by the presence of pervasive dissipation. To overcome this problem in electrical circuits, the alternative paradigm of power shaping was introduced in Ortega, Jeltsema, and Scherpen (2003)-where, as suggested by its name, stabilization is achieved shaping a function akin to the power instead of the energy function. In this paper we extend this technique to general nonlinear systems. The method relies on the solution of a PDE, which ide...

  8. CONTROLLER DESIGN FOR HYBRID POWER SYSTEMS

    N.Prabhu

    2015-01-01

    Full Text Available In this paper an efficient design along with modeling and simulation of a transformer-less small-scale centralized AC—bus Connected Hybrid (Wind–PV power system for supplying electric power to a single phase load. The main components of the hybrid system are: a PV generator (PVG; and an array of horizontal-axis, fixed pitch, small-size, variable-speed wind turbines (WTs with direct-driven permanent magnet synchronous generator (PMSG having an embedded uncontrolled bridge rectifier. An overview of the basic theory of such systems along with their modeling and simulation via Simulink/MATLAB software package are presented. An intelligent control method is applied to the proposed configuration to simultaneously achieve three desired goals: to extract maximum power from each hybrid power system component (PVG and WTs; to guarantee DC voltage regulation/stabilization at the input of the inverter; to transfer the total produced electric power to the electric load.

  9. Power Generation and Distribution via Distributed Coordination Control

    Kim, Byeong-Yeon; Oh, Kwang-Kyo; Ahn, Hyo-Sung

    2014-01-01

    This paper presents power coordination, power generation, and power flow control schemes for supply-demand balance in distributed grid networks. Consensus schemes using only local information are employed to generate power coordination, power generation and power flow control signals. For the supply-demand balance, it is required to determine the amount of power needed at each distributed power node. Also due to the different power generation capacities of each power node, coordination of pow...

  10. Power control electronics for cryogenic instrumentation

    Ray, Biswajit; Gerber, Scott S.; Patterson, Richard L.; Myers, Ira T.

    1995-01-01

    In order to achieve a high-efficiency high-density cryogenic instrumentation system, the power processing electronics should be placed in the cold environment along with the sensors and signal-processing electronics. The typical instrumentation system requires low voltage dc usually obtained from processing line frequency ac power. Switch-mode power conversion topologies such as forward, flyback, push-pull, and half-bridge are used for high-efficiency power processing using pulse-width modulation (PWM) or resonant control. This paper presents several PWM and multiresonant power control circuits, implemented using commercially available CMOS and BiCMOS integrated circuits, and their performance at liquid-nitrogen temperature (77 K) as compared to their room temperature (300 K) performance. The operation of integrated circuits at cryogenic temperatures results in an improved performance in terms of increased speed, reduced latch-up susceptibility, reduced leakage current, and reduced thermal noise. However, the switching noise increased at 77 K compared to 300 K. The power control circuits tested in the laboratory did successfully restart at 77 K.

  11. Intelligent distributed control for nuclear power plants

    Klevans, E.H.; Edwards, R.M.; Ray, A.; Lee, K.Y.; Garcia, H.E.: Chavez, C.M.; Turso, J.A.; BenAbdennour, A.

    1991-01-01

    In September of 1989 work began on the DOE University Program grant DE-FG07-89ER12889. The grant provides support for a three year project to develop and demonstrate Intelligent Distributed Control (IDC) for Nuclear Power Plants. The body of this Second Annual Technical Progress report covers the period from September 1990 to September 1991. It summarizes the second year accomplishments while the appendices provide detailed information presented at conference meetings. These are two primary goals of this research. The first is to combine diagnostics and control to achieve a highly automated power plant as described by M.A. Schultz, a project consultant during the first year of the project. This philosophy, as presented in the first annual technical progress report, is to improve public perception of the safety of nuclear power plants by incorporating a high degree automation where greatly simplified operator control console minimizes the possibility of human error in power plant operations. A hierarchically distributed control system with automated responses to plant upset conditions is the focus of our research to achieve this goal. The second goal is to apply this research to develop a prototype demonstration on an actual power plant system, the EBR-II steam plant.

  12. Intelligent distributed control for nuclear power plants

    In September of 1989 work began on the DOE University Program grant DE-FG07-89ER12889. The grant provides support for a three year project to develop and demonstrate Intelligent Distributed Control (IDC) for Nuclear Power Plants. The body of this Second Annual Technical Progress report covers the period from September 1990 to September 1991. It summarizes the second year accomplishments while the appendices provide detailed information presented at conference meetings. These are two primary goals of this research. The first is to combine diagnostics and control to achieve a highly automated power plant as described by M.A. Schultz, a project consultant during the first year of the project. This philosophy, as presented in the first annual technical progress report, is to improve public perception of the safety of nuclear power plants by incorporating a high degree automation where greatly simplified operator control console minimizes the possibility of human error in power plant operations. A hierarchically distributed control system with automated responses to plant upset conditions is the focus of our research to achieve this goal. The second goal is to apply this research to develop a prototype demonstration on an actual power plant system, the EBR-II steam plant

  13. Simulation and reliability analysis of shunt active power filter based on instantaneous reactive power theory

    CUI Yu-long; LIU Hong; WANG Jing-qin; SUN Shu-guang

    2007-01-01

    This paper first discusses the operating principle ofinstantaneous reactive power theory. Then, the theory is introduced into shunt active power filter and its control scheme is studied. Finally, Matlab/Simulink power system toolbox is used to simulate the system. In the simulation model, as the most common harmonic source, 3-phase thyfistor bridge rectifier circuit is constructed.The simulation results before and after the shunt active filter was switched to the system corresponding to different firing angles of the thyristors are presented and analyzed, which demonstrate the practicability and reliability of the proposed shunt active filter scheme.

  14. Model-Based Power Plant Master Control

    Boman, Katarina; Thomas, Jean; Funkquist, Jonas

    2010-08-15

    The main goal of the project has been to evaluate the potential of a coordinated master control for a solid fuel power plant in terms of tracking capability, stability and robustness. The control strategy has been model-based predictive control (MPC) and the plant used in the case study has been the Vattenfall power plant Idbaecken in Nykoeping. A dynamic plant model based on nonlinear physical models was used to imitate the true plant in MATLAB/SIMULINK simulations. The basis for this model was already developed in previous Vattenfall internal projects, along with a simulation model of the existing control implementation with traditional PID controllers. The existing PID control is used as a reference performance, and it has been thoroughly studied and tuned in these previous Vattenfall internal projects. A turbine model was developed with characteristics based on the results of steady-state simulations of the plant using the software EBSILON. Using the derived model as a representative for the actual process, an MPC control strategy was developed using linearization and gain-scheduling. The control signal constraints (rate of change) and constraints on outputs were implemented to comply with plant constraints. After tuning the MPC control parameters, a number of simulation scenarios were performed to compare the MPC strategy with the existing PID control structure. The simulation scenarios also included cases highlighting the robustness properties of the MPC strategy. From the study, the main conclusions are: - The proposed Master MPC controller shows excellent set-point tracking performance even though the plant has strong interactions and non-linearity, and the controls and their rate of change are bounded. - The proposed Master MPC controller is robust, stable in the presence of disturbances and parameter variations. Even though the current study only considered a very small number of the possible disturbances and modelling errors, the considered cases are

  15. Closed loop power control for LTE uplink

    Muhammad, Bilal

    2008-01-01

    This thesis study involves designing, implementing and testing of a novel radio resource control algorithm for the closed loop power control in the LTE uplink. Different values of the path loss compensation factor are investigated in the range 0.7-1.0 and an optimal value of 0.8 as allowed by the LTE standard is proposed. Both the ideal and a more realistic case modeled by including delay, error, and power headroom reporting were studied. Simulation results indicated that the closed loop powe...

  16. Modeling and Control of Grid Side Converter in Wind Power Generation System Based on Synchronous VFDPC with PLL

    Guo, Yougui; Zeng, Ping; Li, Lijuan;

    2011-01-01

    Virtual flux oriented direct power control (VFDPC) is combined space vector modulation (SVM) with PI of DC-link voltage, active power and reactive power to control the grid side converter in wind power generation system in this paper. VFDPC has reached good performances with PLL (phase lock loop......, LCL filter, transformer grid, and control parts, such as PI controllers of DC-link voltage, active power, reactive power, and SVM, and so on. The simulation results have verified that the control strategy is feasible to fit for control of gird currents, active power, reactive power and DC-link voltage...

  17. Active power compensator of the current harmonics based on the instantaneous power theory

    Marian GAICEANU

    2005-12-01

    Full Text Available The quality of the electrical current becomes a major concern. The proliferation of the power electronic converters, which are used extensively to control electrical apparatus in industrial and commercial applications (dc and ac variable speed motor drives, induction furnaces, power line conditioners, and industrial power supplies, is at the origin of the AC current distribution network pollution and the reactive power demand. These power electronic converters typically draw non-sinusoidal currents from the utility, causing interference with adjacent sensitive loads and limit the utilization of the available electrical supply. The quality of the electrical current thus becomes a significant concern for the distributors of energy and their customers. Recent progress as regards technology of the power electronics brings a capacity of compensation and correction of the harmonic distortion generated by the nonlinear loads. In this paper a parallel active filter prototype capable of reducing the total harmonic distortion in the supply for most current source or adjustable speed drive type loads is presented. A 33 kVA active power filter was developed for harmonic and reactive power compensation based on the instantaneous power theory. The active filter configuration requires the measurement of both the load and filter currents. Experimental results from a prototype active power filter confirm the suitability of the proposed approach. The actual 33kVA prototype converter has been built and tested in the SIEI S.p.A. (Italy laboratory under the Marie Curie Post Doctoral research. The active power compensator is controlled by a high performance DSP platform, resulting in the following active filter features: source current reduction up to the 25th harmonic, 10% THD achievable for current source type loads, efficiency above 97%, does not cause resonance with other loads, operation in the presence of unbalanced loads, reactive power and harmonics

  18. Automaticity or active control

    Tudoran, Ana Alina; Olsen, Svein Ottar

    This study addresses the quasi-moderating role of habit strength in explaining action loyalty. A model of loyalty behaviour is proposed that extends the traditional satisfaction–intention–action loyalty network. Habit strength is conceptualised as a cognitive construct to refer to the psychologic......, respectively, between intended loyalty and action loyalty. At high levels of habit strength, consumers are more likely to free up cognitive resources and incline the balance from controlled to routine and automatic-like responses....

  19. Active Control of Suspension Bridges

    Thoft-Christensen, Palle

    In this paper some recent research on active control of very long suspension bridges, is presented. The presentation is based on research work at Aalborg University, Denmark. The active control system is based on movable flaps attached to the bridge girder. Wind load on bridges with or without...... flaps attached to the girder is briefly presented. A simple active control system is discussed. Results from wind tunnel experiments with a bridge section show that flaps can be used effectively to control bridge girder vibrations. Flutter conditions for suspension bridges with and without flaps are...

  20. Multivariable control in nuclear power stations

    Multivariable methods have the potential to improve the control of large systems such as nuclear power stations. Linear-quadratic optimal control is a multivariable method based on the minimization of a cost function. A related technique leads to the Kalman filter for estimation of plant state from noisy measurements. A design program for optimal control and Kalman filtering has been developed as part of a computer-aided design package for multivariable control systems. The method is demonstrated on a model of a nuclear steam generator, and simulated results are presented

  1. VOLTAGE AND POWER LOSS CONTROL IN DISTRIBUTION SYSTEM USING UPFC

    Yuan, Wei; TANG, Aihong; ZHANG, Xiaocheng; Wang, Shaorong

    2012-01-01

    Abstract: A simplified loop distribution system is taken as the object and the main reasons leading to the power loss in the feeder are analysed in this paper. According to the natural power distribution theory of the loop systems, the minimum power distribution in the loop power system is deduced through the extremism method. Thinking about the power control function of the unified power flow controller, the control system for the series side of the unified power flow controller is designed ...

  2. Intelligent distributed control for nuclear power plants

    This project was initiated in September 1989 as a three year project to develop and demonstrate Intelligent Distributed Control (IDC) for Nuclear Power Plants. There were two primary goals of this research project. The first goal was to combine diagnostics and control to achieve a highly automated power plant as described by M.A. Schultz. The second goal was to apply this research to develop a prototype demonstration on an actual power plant system, the EBR-2 steam plant. Described in this Final (Third Annual) Technical Progress Report is the accomplishment of the project's final milestone, an in-plant intelligent control experiment conducted on April 1, 1993. The development of the experiment included: simulation validation, experiment formulation and final programming, procedure development and approval, and experimental results. Other third year developments summarized in this report are: (1) a theoretical foundation for Reconfigurable Hybrid Supervisory Control, (2) a steam plant diagnostic system, (3) control console design tools and (4) other advanced and intelligent control

  3. Optimum Power Output Control of a Wind Turbine Rotor

    S. Wijewardana

    2016-01-01

    Full Text Available An active and optimum controller is applied to regulate the power output from a wind turbine rotor. The controller is synthesized in two steps. The first step defines the equilibrium operation point and ensures that the desired equilibrium point is stable. The stability of the equilibrium point is guaranteed by a control law that is synthesized by applying the methodology of model predictive control (MPC. The method of controlling the turbine involves pitching the turbine blades. In the second step the blade pitch angle demand is defined. This involves minimizing the mean square error between the actual and desired power coefficient. The actual power coefficient of the wind turbine rotor is evaluated assuming that the blade is capable of stalling, using blade element momentum theory. This ensures that the power output of the rotor can be reduced to any desired value which is generally not possible unless a nonlinear stall model is introduced to evaluate the blade profile coefficients of lift and drag. The relatively simple and systematic nonlinear modelling and MPC controller synthesis approach adopted in this paper clearly highlights the main features on the controller that is capable of regulating the power output of the wind turbine rotor.

  4. Power, Control and Status in Physical Education.

    Thomson, Ian

    2003-01-01

    For most of the 20th century, Scottish teacher education in physical education, sport, and recreation were divided by gender and philosophy and provided by two specialist colleges. Analysis of the government's 1986 decision to merge the colleges focuses on the shift in power and control from the self-contained world of physical education to…

  5. Exact Power Constraints in Smart Grid Control

    Trangbæk, K; Petersen, Mette Højgaard; Bendtsen, Jan Dimon;

    2011-01-01

    This paper deals with hierarchical model predictive control (MPC) of smart grid systems. The objective is to accommodate load variations on the grid, arising from varying consumption and natural variations in the power production e.g. from wind turbines. This balancing between supply and demand is...

  6. Process control in nuclear power plants

    Optimum technical design of a nuclear power plant needs to be parallelled by effective process control in the stage of output operation. The author briefly demonstrates the pertinent criteria like operational organization, functional areas, crews, training of staff, process monitoring, industrial safety, incident prevention, and emergency manual. (DG)

  7. Principles of nuclear power station control

    Lecture notes are presented which were first distributed as part of a UKAEA introductory course on reactor technology held during November 1975. The material is presented in a manner which hopefully will enable recent graduates in science and technology to obtain a broad overall picture of the problems involved. A nuclear power station is only one element of a dispersed interconnected arrangement of other nuclear and fossil-fired units which together constitute the national 'grid'. Thus the control of any one station must relate to the objectives of the grid network as a whole. Economic and technological factors are shown to lead to a national power supply operating around 50 Hz. A precise control of the supply frequency is also motivated by economic and technological considerations, and it is achieved by regulating the output power of individual stations. In order to make the whole grid network stable in following the load, it is shown that a satisfactory practical criterion is for each station to be stable when operating in isolation with a variable load. As regards individual stations, several special control problems concerned with individual plant items are discussed; these include controlled reactivity insertions, temperature reactivity time constants and flow instability. A simplified analysis establishes a fundamental relationship between the stored thermal energy of a boiler unit (a function of mechanical construction) and the flexibility of the heat source (nuclear or fossil-fired) if the station is to cope satisfactorily with demands arising from unscheduled losses of other generating sets or transmission capacity. Finally, two basic control schemes for power station operation are described, known as coupled and decoupled control. Each of the control modes has its own merits, which depend on the proposed station operating strategy (base-load or load-following) and the nature of the heat source. (author)

  8. Robustness of damping control implemented by Energy Storage Systems installed in power systems

    Du, W. [The Southeast University, Nanjing (China); The Queen' s University of Belfast, Belfast (United Kingdom); Wang, H.F. [The Queen' s University of Belfast, Belfast (United Kingdom); Cheng, S.; Wen, J.Y. [Huazhong University of Science and Technology (China); Dunn, R. [The University of Bath, Bath (United Kingdom)

    2011-01-15

    An Energy Storage System (ESS) installed in a power system can effectively damp power system oscillations through controlling exchange of either active or reactive power between the ESS and power system. This paper investigates the robustness of damping control implemented by the ESS to the variations of power system operating conditions. It proposes a new analytical method based on the well-known equal-area criterion and small-signal stability analysis. By using the proposed method, it is concluded in the paper that damping control implemented by the ESS through controlling its active power exchange with the power system is robust to the changes of power system operating conditions. While if the ESS damping control is realized by controlling its reactive power exchange with the power system, effectiveness of damping control changes with variations of power system operating condition. In the paper, an example of power system installed with a battery ESS (BESS) is presented. Simulation results confirm the analytical conclusions made in the paper about the robustness of ESS damping control. Laboratory experiment of a physical power system installed with a 35 kJ/7 kW Superconducting Magnetic Energy Storage (SMES) was carried out to evaluate theoretical study. Results are given in the paper, which demonstrate that effectiveness of SMES damping control realized through regulating active power is robust to changes of load conditions of the physical power system. (author)

  9. Intelligent distributed control for nuclear power plants

    In September of 1989 work began on the DOE University Program grant DE-FG07-89ER12889. The grant provides support for a three year project to develop and demonstrate Intelligent Distributed Control (IDC) for Nuclear Power Plants. The body of this First Annual Technical Progress report summarizes the first year tasks while the appendices provide detailed information presented at conference meetings. One major addendum report, authored by M.A. Schultz, describes the ultimate goals and projected structure of an automatic distributed control system for EBR-2. The remaining tasks of the project develop specific implementations of various components required to demonstrate the intelligent distributed control concept

  10. Control Architecture Modeling for Future Power Systems

    Heussen, Kai

    interregional electricity exchange. However, at the same time, it seems that the overall system design cannot keep up by simply adapting in response to changes, but that also new strategies have to be designed in anticipation. Changes to the electricity markets have been suggested to adapt to the limited...... predictability of wind power, and several new control strategies have been proposed, in particular to enable the control of distributed energy resources, including for example, distributed generation or electric vehicles. Market designs addressing the procurement of balancing resources are highly dependent on...... the operation strategies specifying the resource requirements. How should one decide which control strategy and market configuration is best for a future power system? Most research up to this point has addressed single isolated aspects of this design problem. Those of the ideas that fit with current...

  11. Model predictive control for wind power gradients

    Hovgaard, Tobias Gybel; Boyd, Stephen; Jørgensen, John Bagterp

    2015-01-01

    We consider the operation of a wind turbine and a connected local battery or other electrical storage device, taking into account varying wind speed, with the goal of maximizing the total energy generated while respecting limits on the time derivative (gradient) of power delivered to the grid. We...... use the turbine inertia as an additional energy storage device, by varying its speed over time, and coordinate the flows of energy to achieve the goal. The control variables are turbine pitch, generator torque and charge/discharge rates for the storage device, each of which can be varied over given...... ranges. The system dynamics are quite non-linear, and the constraints and objectives are not convex functions of the control inputs, so the resulting optimal control problem is difficult to solve globally. In this paper, we show that by a novel change of variables, which focuses on power flows, we can...

  12. Active control for performance enhancement of electrically controlled rotor

    Lu Yang; Wang Chao

    2015-01-01

    Electrically controlled rotor (ECR) system has the potential to enhance the rotor perfor-mance by applying higher harmonic flap inputs. In order to explore the feasibility and effectiveness for ECR performance enhancement using closed-loop control method, firstly, an ECR rotor perfor-mance analysis model based on helicopter flight dynamic model is established, which can reflect the performance characteristics of ECR helicopter at high advance ratio. Based on the simulation platform, an active control method named adaptive T-matrix algorithm is adopted to explore the feasibility and effectiveness for ECR performance enhancement. The simulation results verify the effectiveness of this closed-loop control method. For the sample ECR helicopter, about 3%rotor power reduction is obtained with the optimum 2/rev flap inputs at the advance ratio of 0.34. And through analyzing the distributions of attack of angle and drag in rotor disk, the underlying physical essence of ECR power reduction is cleared. Furthermore, the influence of the key control parameters, including convergence factor and weighting matrix, on the effectiveness of closed-loop control for ECR performance enhancement is explored. Some useful results are summarized, which can be used to direct the future active control law design of ECR performance enhancement.

  13. Active control for performance enhancement of electrically controlled rotor

    Lu Yang

    2015-10-01

    Full Text Available Electrically controlled rotor (ECR system has the potential to enhance the rotor performance by applying higher harmonic flap inputs. In order to explore the feasibility and effectiveness for ECR performance enhancement using closed-loop control method, firstly, an ECR rotor performance analysis model based on helicopter flight dynamic model is established, which can reflect the performance characteristics of ECR helicopter at high advance ratio. Based on the simulation platform, an active control method named adaptive T-matrix algorithm is adopted to explore the feasibility and effectiveness for ECR performance enhancement. The simulation results verify the effectiveness of this closed-loop control method. For the sample ECR helicopter, about 3% rotor power reduction is obtained with the optimum 2/rev flap inputs at the advance ratio of 0.34. And through analyzing the distributions of attack of angle and drag in rotor disk, the underlying physical essence of ECR power reduction is cleared. Furthermore, the influence of the key control parameters, including convergence factor and weighting matrix, on the effectiveness of closed-loop control for ECR performance enhancement is explored. Some useful results are summarized, which can be used to direct the future active control law design of ECR performance enhancement.

  14. Internal active power reserve management in Large scale PV Power Plants

    Craciun, Bogdan-Ionut; Spataru, Sergiu; Kerekes, Tamas;

    Active Power Reserves (APRs) provided through curtailment (iAPRs) or through auxiliary storage systems (aAPR) with Large scale PV Power Plants (LPVPPs) becomes a reality in the near future with high penetration levels of Photovoltaic (PV) power into the grid. Therefore, this paper analyses the...... solutions for iAPR fulfilment in central inverter based - LPVPPs in terms of their layout, configuration and control architecture. During iAPR supply, the LPVPP has to operate under its Maximum Power Point (MPP), which means that the MPP algorithm has to undergo several changes. For this purpose, the paper...

  15. Power supply control module for magnet power supplies control system of Indus-1

    Optics in a circular accelerator is mainly governed by magnetic field of the magnets in the path of the electron beam. Magnet Power Supplies Control System controls and monitors the power supplies feeding the magnets required to bend, steer, and focus etc the charged particle beam. New Control System for the Magnet Power Supplies of the Indus-1 is being implemented. Based on distributed control architecture in this system, each power supply is connected to an equipment interface unit, referred to as Power Supply Control Module (PSCM). The PSCMs communicate with the user interface layer through a custom protocol over an RS-485 serial bus. The PSCMs are developed using TMS320F28335 Digital Signal Controller (DSC). These are compact 19'' rack mountable systems. The PSCM provides digital control of eight parameters, status monitoring of eight parameters, current setting, and current monitoring with accuracy better than 0.01% and stability better than ±100 ppm. It features the generation of current reference of any programmed shape particularly required for cycling profile, ramping profile etc. Other than these functions, PSCMs also incorporate some features like synchronized data reading and fast data capturing which are useful for the analysis of transient phases of ramping and cycling. The set reference for current and current read-back are sampled at 1KHz and stored in the 512K Word memories in PSCM. The paper describes the PSCM of the new magnet power supplies control system for Indus-1. (author)

  16. Control method for BWR type power plant

    The present invention provides a method of controlling a BWR type plant having internal pumps capable of sufficiently utilizing the performance of a whole volume turbine bypass plant to enable stable supply of electric power upon load interruption of power generator thereof. Namely, upon occurrence of load interruption of a power generator or turbine trip, a plurality of internal pumps are tripped simultaneously to abruptly reduce a reactor core flow rate by a predetermined value or more. In this case, a reactor core flow rate abruptly reduction scram signal is prevented. Alternatively, a plurality of internal pumps are tripped simultaneously to abruptly reduce the reactor core flow rate. In this case, a reactor core flow rate abrupt reduction scram set value is changed in order to inhibit the reactor core flow rate abrupt reduction scram signal. With such procedures, upon load interruption of power generator or upon trip of turbine, reactor core flow rate is abruptly reduced by trip of internal pumps for avoiding increase of neutron fluxes due to reactor pressure change. However, since reactor scram is avoided, the operation can be continued upon load interruption of power generator. As a result, performance of whole volume turbine bypass plant can be utilized sufficiently even upon occurrence of load interruption of power generator. (I.S.)

  17. Piezoelectric transformer based power converters; design and control

    Rødgaard, Martin Schøler

    the advantage of being purely primary side based. A revolutionary bi-directional control method is proposed, which utilizes active phase shift of the output rectifier that enables bi-directional power flow. Soft switching operation is maintained over the full power flow modulation range, ensuring optimal......The last two decades of research into piezoelectric transformer (PT) based power converters have led to some extensive improvements of the technology, but it still struggles to get its commercial success. This calls for further research and has been the subject of this work, in order to enable...... the utilization of the PT technology advantages, reduce cost and increase competitiveness. First of all an overview of the basic PT technology used in general power converters is given, including the basic piezoelectric nature, converter topologies and control methods. Compared to traditional magnetic technology...

  18. An Active Power Control Method of Large-Scale Wind Farm Considering Security Constraints of Tie Lines%考虑断面安全约束的大规模风电有功控制

    卓峻峰; 金学洙; 邓波; 尚学伟; 赵林; 汤伟; 刘诚哲

    2015-01-01

    ABSTRACT:With rapid increasing of the installed capacity of wind power generation units and grid-connection of large-scale wind farms, the fluctuation of large-scale wind power generation and hierarchical features of the tie line of wind farms bring difficulties to real-time scheduling of power grids and the waste of the wind energy resource may occur, for this reason an active power control method based on the hierarchical tie line of large-scale wind farm is proposed. Since the power generation of wind farm is restricted to the constraints of tie lines belonging to different hierarchies, by means of allocating wind farm power regulation among wind farms in the wide area, depth-first searching out-of-limit tie lines and transferring power generation capability, the full and fair utilization of the power of wind farms under the premise of ensuring the security of tie lines is realized. Results of case study and power grid operation show that the proposed method is reasonable and feasible, and is available for reference to the active power control of hierarchical tie lines of large-scale wind farms.%随着风电装机容量的快速增长和大规模风电的并网接入,大规模风电的波动性和风电断面的分层特征给电力系统实时调度带来困难,可能出现风能资源的浪费,为此提出一种大规模风电分层断面的有功控制方法。风电场的发电受制于各级输电断面的约束,通过对各风电场广域分配调节功率,深度优先搜索越限断面和发电能力转移的方法,实现了保证断面安全前提下的风电场功率的充分利用和公平利用。实际算例和电力系统的运行结果验证了该方法的合理性和可行性,为大规模风电分层断面的有功控制提供了一种有效方法。

  19. Development the Controller Input Power of Peripheral Interfacing Controller Using Other Micro controller

    This Controller Input Power of a Peripheral Interfacing Controller was developed using the other micro controller. This paper discuss the switching technique are practiced using proper electronic device to develop the controller, thus enable to control the input power of a PIC in order to expand their interfacing capacity and control. This may allow the PIC could be used to acquire input and control output signal from electronic and electromechanical device and instrument as well as software in wide scale and application. (author)

  20. Power flow controller with a fractionally rated back-to-back converter

    Divan, Deepakraj M.; Kandula, Rajendra Prasad; Prasai, Anish

    2016-03-08

    A power flow controller with a fractionally rated back-to-back (BTB) converter is provided. The power flow controller provide dynamic control of both active and reactive power of a power system. The power flow controller inserts a voltage with controllable magnitude and phase between two AC sources at the same frequency; thereby effecting control of active and reactive power flows between the two AC sources. A transformer may be augmented with a fractionally rated bi-directional Back to Back (BTB) converter. The fractionally rated BTB converter comprises a transformer side converter (TSC), a direct-current (DC) link, and a line side converter (LSC). By controlling the switches of the BTB converter, the effective phase angle between the two AC source voltages may be regulated, and the amplitude of the voltage inserted by the power flow controller may be adjusted with respect to the AC source voltages.

  1. Design and analysis of an active power factor correction circuit

    Zhou, Zhen

    1989-01-01

    The design of an active-unity power factor correction circuit with variable-hysteresis control for off-line dc-to-dc switching power supplies is described. Design equations relating the boost inductor current ripple to the circuit components selection and circuit performance arc discussed. A computer-aided design program (CADO) is developed to give the optimal circuit components selection. A 500 watt, 300 volt experimental circuit is built to verify the simulation and analysis ...

  2. Integrating Autonomous Load Controllers in Power Systems

    Douglass, Philip James

    Electric energy systems stand on the brink of radical change as the urgent need to reduce greenhouse gas emissions pushes more efficient utilization of energy resources and the adoption of renewable energy sources. New renewable sources such as wind and solar have a large potential, but they are...... characterized by variable generation that is only partly predictable. Managing loads is already used in limited circumstances to improve security and efficiency of the power system. In power systems with a large penetration of variable generation, load management has large role to play in adapting consumption......-time constraints and reliability constraints in power systems are motivating research into new control architectures suitable for such a large and complex system. The focus of this thesis is on an intermediate stage of evolution between today's largely passive loads and a future "Internet of Things". Specifically...

  3. Variable Structure Control of DFIG for Wind Power Generation and Harmonic Current Mitigation

    Belmadani, B.; R. Wamkeue; KAIRUS, D.; BENGHANEM, M.

    2010-01-01

    This paper focuses on wind energy conversion system (WECS) analysis and control for power generation along with problems related to the mitigation of harmonic pollution in the grid using a variable-speed structure control of the doubly fed induction generator (DFIG). A control approach based on the so-called sliding mode control (SMC) that is both efficient and suitable is used for power generation control and harmonic-current compensation. The WECS then behaves as an active power filter ...

  4. Microprocessor system for low power feedwater control

    The results of an ongoing Combustion Engineering development program to improve steam generator level control during low power operation are presented. A discussion is presented on the analytical tools, the verification process and the simulation capabilities that are currently available for the design and evaluation of advanced steam generator control systems. A review is then presented on the dynamic processes internal to the steam generator that must be controlled, the conceptual approach used in arriving at a design, followed by the verification of the design using a detailed digital simulation of the process and the control system. Finally, a discussion is presented on the reasons for the selection of a microprocessor based systems over a conventional analog system and the potential improvements in reliability and flexibility

  5. Controller For Standalone Hybrid Renewable Power Generation

    P. Madhu Prabhuraj #1 R.M. Sasiraja

    2013-01-01

    The project utilizes the resources available locally like sunlight, wind and biogas plant which can be installed with aids from government. A controller is designed to switch between generation sources with preference to renewable modes. When renewable energy is excess, the biogas is shut down and the power is used to pump water to a higher level, which can later be used for agriculture and micro hydro generation. In the hybrid system, energy has a higher reliability, can be cost effective an...

  6. Improvement of active filter for HIMAC power sources

    For the power sources of the synchrotron electromagnets for the heavy particle beam cancer therapy apparatus HIMAC in National Institute of Radiological Science, in order to stabilize the taken-out beam, the ripple property as low as below 1 x 10-6 is required. As for this electromagnet power sources, various devices were applied to lower ripples, and the required specifications have been satisfied. Also the beam spill is stable, but slight variation has been observed, therefore, by improving the performance of the active filter, the ripples were improved. The specifications of the electromagnet power sources and the whole constitution of the power source system are shown. In the HIMAC power sources, the means for having realized the low ripple performance so far are explained. Those are the absorption of the ineffective power generated from the power sources, the control of the ripples of common made due to the transducer thyristor, and the sure compensation of ripples by the control circuit for the power sources. By adding the band pass filters to the active filter, its characteristics were improved. As the result, 1200 Hz ripple component was reduced by 41 db, thus the sufficient effect was obtained. Hereafter, by the high sensitivity measurement of the current of electromagnets and the evaluation of magnetic fields, the validity will be evaluated. (K.I.)

  7. The function of the alarm system in advanced control rooms: an analysis of operator visual activity during a simulated nuclear power plant disturbance

    In 1996, the US Nuclear Regulatory Commission, Brookhaven National Laboratory (US), and the OECD Halden Reactor Project conducted a large experiment, investigating the effects of alarm reduction and display on operator and plant performance (O'Hara et al., 1997), The results from this experiment indicated that the number of alarms presented to the operators, and the type of alarm display, had no impact on human performance during simulated disturbances. One possible interpretation of these surprising results is that operators in advanced control rooms use the alarm system only for limited purposes, i.e., the introduction of process formats, trend curves, overview displays, and computerized support systems have made the alarm system superfluous. Given the massive efforts put into the design and development of sophisticated alarm systems intended to maximize safety, this would be a paradoxical conclusion. To explore the role of the alarm system in more detail, we performed an analysis of eye-movement tracking data collected in the Halden Man-Machine Laboratory (HAMMLAB). The objective of the study was to examine to which extent, and for what purposes, licensed operators use the alarm system in advanced control rooms during complex problem solving. According to Funke (1991), complex problem solving situations are non-transparent, ill-defined, and dynamic, i.e., the underlying state of the system must be inferred from symptoms, the goal state is ambiguous, and the problem is in continuous change. This seems to be an appropriate description of the working conditions when operators are confronted with challenging scenarios in a full scope nuclear simulator. Five experts on nuclear power plant operation from the OECD Halden Reactor Project were convened in order to generate initial hypotheses about the operators' use of the alarm system. The expert panel estimated that operators in advanced control rooms would use the alarm system less than 10 percent of the available

  8. Impact of wind power in autonomous power systems—power fluctuations—modelling and control issues

    Margaris, Ioannis D.; Hansen, Anca Daniela; Cutululis, Nicolaos Antonio;

    2011-01-01

    This paper describes a detailed modelling approach to study the impact of wind power fluctuations on the frequency control in a non-interconnected system with large-scale wind power. The approach includes models for wind speed fluctuations, wind farm technologies, conventional generation...

  9. Nuclear power plant control room operator control and monitoring tasks

    Oak Ridge National Laboratory is conducting a research project the purpose of which is to develop the technical bases for regulatory review criteria for use in evaluating the safety implications of human factors associated with the use of artificial intelligence and expert systems, and with advanced instrumentation and control (I and C) systems in nuclear power plants (NPP). This report documents the results from Task 8 of that project. The primary objectives of the task was to identify the scope and type of control and monitoring tasks now performed by control-room operators. Another purpose was to address the types of controls and safety systems needed to operate the nuclear plant. The final objective of Task 8 was to identify and categorize the type of information and displays/indicators required to monitor the performance of the control and safety systems. This report also discusses state-of-the-art controls and advanced display devices which will be available for use in control-room retrofits and in control room of future plants. The fundamental types of control and monitoring tasks currently conducted by operators can be divided into four classifications: function monitoring tasks, control manipulation tasks, fault diagnostic tasks, and administrative tasks. There are three general types of controls used in today's NPPs, switches, pushbuttons, and analog controllers. Plant I and C systems include components to achieve a number of safety-related functions: measuring critical plant parameters, controlling critical plant parameters within safety limits, and automatically actuating protective devices if safe limits are exceeded. The types of information monitored by the control-room operators consist of the following parameters: pressure, fluid flow and level, neutron flux, temperature, component status, water chemistry, electrical, and process and area radiation. The basic types of monitoring devices common to nearly all NPP control rooms include: analog meters

  10. Nuclear power plant control room operator control and monitoring tasks

    Bovell, C.R.; Beck, M.G. [Concord Associates, Inc., Knoxville, TN (United States); Carter, R.J. [Oak Ridge National Labs., TN (United States)

    1998-07-01

    Oak Ridge National Laboratory is conducting a research project the purpose of which is to develop the technical bases for regulatory review criteria for use in evaluating the safety implications of human factors associated with the use of artificial intelligence and expert systems, and with advanced instrumentation and control (I and C) systems in nuclear power plants (NPP). This report documents the results from Task 8 of that project. The primary objectives of the task was to identify the scope and type of control and monitoring tasks now performed by control-room operators. Another purpose was to address the types of controls and safety systems needed to operate the nuclear plant. The final objective of Task 8 was to identify and categorize the type of information and displays/indicators required to monitor the performance of the control and safety systems. This report also discusses state-of-the-art controls and advanced display devices which will be available for use in control-room retrofits and in control room of future plants. The fundamental types of control and monitoring tasks currently conducted by operators can be divided into four classifications: function monitoring tasks, control manipulation tasks, fault diagnostic tasks, and administrative tasks. There are three general types of controls used in today`s NPPs, switches, pushbuttons, and analog controllers. Plant I and C systems include components to achieve a number of safety-related functions: measuring critical plant parameters, controlling critical plant parameters within safety limits, and automatically actuating protective devices if safe limits are exceeded. The types of information monitored by the control-room operators consist of the following parameters: pressure, fluid flow and level, neutron flux, temperature, component status, water chemistry, electrical, and process and area radiation. The basic types of monitoring devices common to nearly all NPP control rooms include: analog meters

  11. Robustness of Damping Control Implemented by Energy Storage Systems Installed in Power Systems

    Wang, Haifeng; Du, W.; Chen, S. J.; Wen, J.Y.; Dunn, R

    2011-01-01

    An energy storage system (ESS) installed in a power system can effectively damp power system oscillations through controlling exchange of either active or reactive power between the ESS and power system. This paper investigates the robustness of damping control implemented by the ESS to the variations of power system operating conditions. It proposes a new analytical method based on the well-known equal-area criterion and small-signal stability analysis. By using the proposed method, it is co...

  12. Optical control of antibacterial activity

    Velema, Willem A.; van der Berg, Jan Pieter; Hansen, Mickel J.; Szymanski, Wiktor; Driessen, Arnold J. M.; Feringa, Ben L.

    2013-11-01

    Bacterial resistance is a major problem in the modern world, stemming in part from the build-up of antibiotics in the environment. Novel molecular approaches that enable an externally triggered increase in antibiotic activity with high spatiotemporal resolution and auto-inactivation are highly desirable. Here we report a responsive, broad-spectrum, antibacterial agent that can be temporally activated with light, whereupon it auto-inactivates on the scale of hours. The use of such a ‘smart’ antibiotic might prevent the build-up of active antimicrobial material in the environment. Reversible optical control over active drug concentration enables us to obtain pharmacodynamic information. Precisely localized control of activity is achieved, allowing the growth of bacteria to be confined to defined patterns, which has potential for the development of treatments that avoid interference with the endogenous microbial population in other parts of the organism.

  13. Instrumentation and control of nuclear power plant

    This report outlines major instruments, man-machine systems in particular, that have been developed recently for nuclear power plants. The TMI accident triggered the reinforcement of man-machine interface systems in many nuclear power plants over the world. In Japan, new types of control panels have been successively adopted for practical applications. These central control panels are characterized by their designs based on basic theories of human engineering, the use of CRT's for efficient plant monitoring, and the effective utilization of computers to permit centralization of data and simplification of operations. Based on the lessons learned from the TMI accidents, various operator supporting systems have been developed in many countries to allow operators to obtain reactor data during their operation work. These systems play an important role especially in case of emergency. Such systems include safety parameter display systems and disturbance analysis systems. Digital instruments have been adopted more widely for the control of major systems including the nuclear reactor as high-performance, high-function microprocessors emerged. Other newly developed systems include highly reliable emergency systems, load following control systems, safety systems equipped with a microprocessor, and training simulators. (Nogami, K.)

  14. 基于自抗扰控制器的直驱式永磁同步风电系统双PWM控制%Direct-drive permanent magnet synchronous wind power generation system based on active disturbance rejection controller

    伍亮; 杨金明; 贾盼盼

    2013-01-01

    Based on the mathematical model of direct-drive permanent magnet synchronous wind power generation system,the active disturbance rejection controllers (ADRC) are designed for the generator-side converter and the grid-side converter respectively.Using the ADRC,the wind power generation system with dual PWM converter can track maximum power point by the generator-side converter and maintain a constant voltage of DC capacitor by the grid-side converter under rated wind speed.The simulation result shows that comparing with the traditional PI controller,wind power generation system with ADRC can track the reference turbine speed quickly without overshoot.At the same time,voltage disturbance on DC capacitor caused by the variation of wind speed and grid voltage disturbance is effectively restrained.So the wind power generation system with ADRC has outstanding control performance.%针对直驱式永磁同步风力发电机组,分别设计了电机侧和电网侧的变换器自抗扰控制器,从而实现在额定风速以下对电机侧的最大风能跟踪控制、电网侧直流电容电压恒定控制.与常规PI控制器相比,采用自抗扰控制器的直驱动式永磁同步发电系统,能够实现对指令转速快速及无超调跟踪、有效抑制风速变化及电网电压扰动对电容电压的影响,具有较为优秀的控制性能.

  15. Fractional active disturbance rejection control.

    Li, Dazi; Ding, Pan; Gao, Zhiqiang

    2016-05-01

    A fractional active disturbance rejection control (FADRC) scheme is proposed to improve the performance of commensurate linear fractional order systems (FOS) and the robust analysis shows that the controller is also applicable to incommensurate linear FOS control. In FADRC, the traditional extended states observer (ESO) is generalized to a fractional order extended states observer (FESO) by using the fractional calculus, and the tracking differentiator plus nonlinear state error feedback are replaced by a fractional proportional-derivative controller. To simplify controller tuning, the linear bandwidth-parameterization method has been adopted. The impacts of the observer bandwidth ωo and controller bandwidth ωc on system performance are then analyzed. Finally, the FADRC stability and frequency-domain characteristics for linear single-input single-output FOS are analyzed. Simulation results by FADRC and ADRC on typical FOS are compared to demonstrate the superiority and effectiveness of the proposed scheme. PMID:26928516

  16. Active control: Wind turbine model

    Bindner, H.

    1999-01-01

    This report is a part of the reporting of the work done in the project 'Active Control of Wind Turbines'. This project aim is to develop a simulation model for design of control systems for turbines with pitch control and to use that model to designcontrollers. This report describes the model...... developed for controller design and analysis. Emphasis has been put on establishment of simple models describing the dynamic behavior of the wind turbine in adequate details for controller design. This hasbeen done with extensive use of measurements as the basis for selection of model complexity and model....... The models are all formulated as linear differential equations. The models are validated throughcomparisons with measurements performed on a Vestas WD 34 400 kW wind turbine. It is shown from a control point of view simple linear models can be used to describe the dynamic behavior of a pitch...

  17. Power Control of Permanent Magnet Generator Based Variable Speed Wind Turbines

    Deng, Fujin; Chen, Zhe

    2009-01-01

    When the wind power accounts for a large portion of the grid, it will be required to regulate the active power and reactive power. This paper investigates a MWlevel variable speed wind turbine with a permanent magnet synchronous generator (PMSG). The power control capabilities of two kinds of...

  18. Stability and control of wind farms in power systems

    Jauch, Clemens

    2006-01-01

    The Ph.D. project ‘Stability and Control of Wind Farms in Power Systems’ deals with some selected problems related to wind power in power systems. With increasing wind power penetration, wind turbines substitute the power production of conventional powerplants. Therefore, wind turbines also have to take over the power system stabilisation and control tasks, that were traditionally carried out by conventional power plants. Out of the many aspects related to this problem, this project focuses o...

  19. Preventive maintenance activities for nuclear power station

    The supply of stable electric power by getting rid of the failures of nuclear power plants is an important factor for obtaining reliance and social acceptance for nuclear power plants as power sources. Electric power companies have improved their installations as well as carried out maintenance during operation, regular inspection and arrangement. Nuclear plant manufacturers not only implement maintenance and facility-improving works at the request of electric power companies, but also have charge of cooperation in maintenance planning, maintenance engineering services such as operation and repair data analysis and the development of working robots for maintenance. This paper introduces the maintenance activities presently performed by Hitachi Ltd., that is (1) servicing activities for supporting maintenance centering around the Nuclear Plant Service Center; (2) maintenance works in regular inspection; (3) maintenance engineering services to offer preventive maintenance data; and (4) the automation of maintenance works and the development of working robots for reducing exposure to radiation. The robots for nuclear plants are roughly divided into the following four types, and the results of using robots are described. They are exchange machines for replacing reactor or auxiliary components; inspection machines for monitoring plant conditions during reactor operation and for inspection works during shutdown; decontamination machines for reducing radiation dose of reactor equipment; and machining robots for reactor equipment reconstruction or repairing works. (Wakatsuki, Y.)

  20. Junction temperature measurements via thermo-sensitive electrical parameters and their application to condition monitoring and active thermal control of power converters

    Baker, Nick; Liserre, Marco; Dupont, L.; Avenas, Y.

    The temperature of a power semiconductor device is important for both its optimal operation and reliability. If the temperature is known during the operation of a converter, it can be used to monitor the health of power modules: a measurement of aging, scheduling of maintenance, or even implement...

  1. ABOUT CONTROLLING OF SCIENTIFIC ACTIVITY

    Mukhin V. V.

    2014-06-01

    Full Text Available We have selected the new area of controlling - scientific activity controlling. We consider some problems of development in this field, primarily the problem of selection of key performance indicators. It’s been founded that administrative measures stimulated the pursuit of a number of articles published in scientific journals hinders the development of science. Methodological errors - emphasis on citation indexes, impact factors, etc. - lead to wrong management decisions. As the experience of the UK, an expertise should be applied in the management of science. The article briefly discusses some of the drawbacks of the system of scientific specialties. It is proposed to expand research on the science of science and scientific activity controlling. We have also discussed the problems of controlling in applied research organizations

  2. Controller For Standalone Hybrid Renewable Power Generation

    P. Madhu Prabhuraj #1 R.M. Sasiraja

    2013-06-01

    Full Text Available The project utilizes the resources available locally like sunlight, wind and biogas plant which can be installed with aids from government. A controller is designed to switch between generation sources with preference to renewable modes. When renewable energy is excess, the biogas is shut down and the power is used to pump water to a higher level, which can later be used for agriculture and micro hydro generation. In the hybrid system, energy has a higher reliability, can be cost effective and improve the quality of life in small town. At large scale and hybrid system will independently provide a stable power source and daily gas for small towns. Hybrid power system that aims to increase the system efficiency and increase use of renewable energy based hybrid power system. In order to meet sustained load demands during varying natural conditions, different renewable energy sources need to be integrated with each other like solar ,wind , waste of energy municipal waste/ liquid waste, small hydro.

  3. High performance direct instantaneous power control of PWM rectifiers

    This paper presents a new direct instantaneous power control (DPC) strategy for active rectifiers. In this novel scheme the PWM modulator has been utilized instead of the hysteresis comparators and switching table. The required converter voltage in each sampling period is directly calculated based on the reference and measured values of powers, system parameters, and the measured voltage of the AC source through simple equations which are wisely compensated for variations of the grid voltage during a sampling period. Then, the PWM generator generates the switching pulses for the voltage source converter. It is shown that the proposed DPC-PWM exhibits several features, such as a simple algorithm, constant switching frequency, robust to sampling frequency changes, robust to inductance values mismatch, and particularly it provides low sampling frequency. Extensive simulation and experimental results have proven the excellent performance and verify the validity and effectiveness of the proposed instantaneous power control scheme.

  4. FPGA for Power Control of MSL Avionics

    Wang, Duo; Burke, Gary R.

    2011-01-01

    A PLGT FPGA (Field Programmable Gate Array) is included in the LCC (Load Control Card), GID (Guidance Interface & Drivers), TMC (Telemetry Multiplexer Card), and PFC (Pyro Firing Card) boards of the Mars Science Laboratory (MSL) spacecraft. (PLGT stands for PFC, LCC, GID, and TMC.) It provides the interface between the backside bus and the power drivers on these boards. The LCC drives power switches to switch power loads, and also relays. The GID drives the thrusters and latch valves, as well as having the star-tracker and Sun-sensor interface. The PFC drives pyros, and the TMC receives digital and analog telemetry. The FPGA is implemented both in Xilinx (Spartan 3- 400) and in Actel (RTSX72SU, ASX72S). The Xilinx Spartan 3 part is used for the breadboard, the Actel ASX part is used for the EM (Engineer Module), and the pin-compatible, radiation-hardened RTSX part is used for final EM and flight. The MSL spacecraft uses a FC (Flight Computer) to control power loads, relays, thrusters, latch valves, Sun-sensor, and star-tracker, and to read telemetry such as temperature. Commands are sent over a 1553 bus to the MREU (Multi-Mission System Architecture Platform Remote Engineering Unit). The MREU resends over a remote serial command bus c-bus to the LCC, GID TMC, and PFC. The MREU also sends out telemetry addresses via a remote serial telemetry address bus to the LCC, GID, TMC, and PFC, and the status is returned over the remote serial telemetry data bus.

  5. Power supply controlled for plasma torch generation

    The high density of energy furnished by thermal plasma is profited in a wide range of applications, such as those related with welding fusion, spray coating and at the present in waste destruction. The waste destruction by plasma is a very attractive process because the remaining products are formed by inert glassy grains and non-toxic gases. The main characteristics of thermal plasmas are presented in this work. Techniques based on power electronics are utilized to achieve a good performance in thermal plasma generation. This work shown the design and construction of three phase control system for electric supply of thermal plasma torch, with 250 kw of capacity, as a part of the project named 'Destruction of hazard wastes by thermal plasma' actually working in the Instituto Nacional de Investigaciones Nucleares (ININ). The characteristics of thermal plasma and its generation are treated in the first chapter. The A C controllers by thyristors applied in three phase arrays are described in the chapter II, talking into account the power transformer, rectifiers bank and aliasing coil. The chapter III is dedicated in the design of the trigger module which controls the plasma current by varying the trigger angle of the SCR's; the protection and isolating unit are also presented in this chapter. The results and conclusions are discussed in chapter IV. (Author)

  6. Simulation Research on Integrated Control of Vehicle Semi-active Suspension and Power Steering%车辆半主动悬架与助力转向集成控制的仿真研究

    汪少华; 陈龙; 袁传义

    2009-01-01

    For coordinating handling stability and ride comfort of vehicle, based on the principle of chassis system dynamics, a combined model for semi-active suspension (SAS) and electric power steering (EPS) is set up for imposing integrated control on the systems of SAS and EPS. Quadratic feedback and PID strategies are used to control the adjustable damping of suspension and the assistant power of EPS respectively. The simulation results show that with integrated control, the handling stability and ride comfort of vehicle are both superior to that with sep-arate control on suspension or steering.%为协调车辆操纵稳定性和行驶平顺性,基于底盘系统动力学原理,建立了半主动悬架和电动助力转向的综合模型,对半主动悬架和电动助力转向系统进行集成控制.运用二次反馈法和PID策略分别对悬架的可调阻尼和转向系统的助力进行控制.仿真结果表明,在集成控制情况下,车辆的操纵稳定性和平顺性均优于悬架或转向单独控制的效果.

  7. Dynamics and control of nuclear power plants

    A mathematical model of the power plant with a pressurized water reactor has been prepared and tested. The model is intended for a schematic simulator based on a digital computer. The results of the simulation run for various normal transients are in good agreement with literature data. Equipment for computer control of the experimental reactor TRIGA has been completed. The equipment includes two microcomputers and associated interface circuits. Presently, only data logging is performed. The analyses of random signals on the TRIGA reactor have been continued. Measurements of neutron flux, fuel temperature and cooling water duct have been performed

  8. Transforming the Duke Power work control process

    Faced with rising operating and maintenance costs, Duke Power initiated a Work Control Project to provide fundamental rethinking, dramatic quality improvements, and a dramatic reduction in inefficiencies. Other aims were: to do more better with less, to improve coordination between work groups, reduce paperwork, increase effectiveness and utilization of station personnel, and achieve consistent implementation between sites. The existing electronic work management scheme needed some modifications to its software, especially, the programming of a screen to allow simple entry of corrective problems, and the implementation of the new scheduling process. The project has been successful in speeding up the resolution of problems, and in reducing backlogs of maintenance work

  9. Power and control in gay strip clubs.

    DeMarco, Joseph R G

    2007-01-01

    The gay strip club is a place in which more than displays of male beauty take place. The mix of customers, performers, liquor, and nudity results in fascinating dynamics. Of interest in this article are the power relationships and issues of control played out both among and between strippers and customers. Based on extensive participant observation conducted in eight cities and numerous bars/clubs and including more than 150 in-depth interviews, this article concerns just one aspect of the world of male strippers who perform for men. PMID:18019071

  10. A Turbine-powered UAV Controls Testbed

    Motter, Mark A.; High, James W.; Guerreiro, Nelson M.; Chambers, Ryan S.; Howard, Keith D.

    2007-01-01

    The latest version of the NASA Flying Controls Testbed (FLiC) integrates commercial-off-the-shelf components including airframe, autopilot, and a small turbine engine to provide a low cost experimental flight controls testbed capable of sustained speeds up to 200 mph. The series of flight tests leading up to the demonstrated performance of the vehicle in sustained, autopiloted 200 mph flight at NASA Wallops Flight Facility's UAV runway in August 2006 will be described. Earlier versions of the FLiC were based on a modified Army target drone, AN/FQM-117B, developed as part of a collaboration between the Aviation Applied Technology Directorate at Fort Eustis, Virginia and NASA Langley Research Center. The newer turbine powered platform (J-FLiC) builds on the successes using the relatively smaller, slower and less expensive unmanned aerial vehicle developed specifically to test highly experimental flight control approaches with the implementation of C-coded experimental controllers. Tracking video was taken during the test flights at Wallops and will be available for presentation at the conference. Analysis of flight data from both remotely piloted and autopiloted flights will be presented. Candidate experimental controllers for implementation will be discussed. It is anticipated that flight testing will resume in Spring 2007 and those results will be included, if possible.

  11. Active micromachines: Microfluidics powered by mesoscale turbulence.

    Thampi, Sumesh P; Doostmohammadi, Amin; Shendruk, Tyler N; Golestanian, Ramin; Yeomans, Julia M

    2016-07-01

    Dense active matter, from bacterial suspensions and microtubule bundles driven by motor proteins to cellular monolayers and synthetic Janus particles, is characterized by mesoscale turbulence, which is the emergence of chaotic flow structures. By immersing an ordered array of symmetric rotors in an active fluid, we introduce a microfluidic system that exploits spontaneous symmetry breaking in mesoscale turbulence to generate work. The lattice of rotors self-organizes into a spin state where neighboring discs continuously rotate in permanent alternating directions due to combined hydrodynamic and elastic effects. Our virtual prototype demonstrates a new research direction for the design of micromachines powered by the nematohydrodynamic properties of active turbulence. PMID:27419229

  12. Active micromachines: Microfluidics powered by mesoscale turbulence

    Thampi, Sumesh P; Shendruk, Tyler N; Golestanian, Ramin; Yeomans, Julia M

    2016-01-01

    Dense active matter, from bacterial suspensions and microtubule bundles driven by motor proteins to cellular monolayers and synthetic Janus particles, is characterised by mesoscale turbulence, the emergence of chaotic flow structures. By immersing an ordered array of symmetric rotors in an active fluid, we introduce a microfluidic system that exploits spontaneous symmetry breaking in mesoscale turbulence to generate work. The lattice of rotors self-organises into a spin-state where neighbouring discs continuously rotate in permanent alternating directions due to combined hydrodynamic and elastic effects. Our virtual prototype demonstrates a new research direction for the design of micromachines powered by the nematohydrodynamic properties of active turbulence.

  13. Active micromachines: Microfluidics powered by mesoscale turbulence

    Thampi, Sumesh P.; Doostmohammadi, Amin; Shendruk, Tyler N.; Golestanian, Ramin; Yeomans, Julia M.

    2016-01-01

    Dense active matter, from bacterial suspensions and microtubule bundles driven by motor proteins to cellular monolayers and synthetic Janus particles, is characterized by mesoscale turbulence, which is the emergence of chaotic flow structures. By immersing an ordered array of symmetric rotors in an active fluid, we introduce a microfluidic system that exploits spontaneous symmetry breaking in mesoscale turbulence to generate work. The lattice of rotors self-organizes into a spin state where neighboring discs continuously rotate in permanent alternating directions due to combined hydrodynamic and elastic effects. Our virtual prototype demonstrates a new research direction for the design of micromachines powered by the nematohydrodynamic properties of active turbulence. PMID:27419229

  14. Special Nuclear Material Control by the Power Reactor Operator

    A relatively new and extremely valuable fuel for electric power production, uranium, requires very careful inventory control from the time the reactor operator assumes financial responsibility for this material until, as partially expended fuel, it is transferred to another facility and the remaining part of its initial value is recovered. Most power reactor operators were operating fossil-fuelled power plants before the advent of nuclear power and have long since established rather complete and adequate controls for these fossil fuels. The reactor operator must have no less adequate controls for the special nuclear material used in his nuclear plant. Power reactor, operation is not an ancient science and during its relatively short history our engineers and scientists have been constantly improving plant designs and methods of operation to reduce costs and make our nuclear plants competitive with fossil-fuelled conventional plants. Nuclear material management must be as modern and efficient as is humanly possible to ensure that technological advances leading to reduced costs are not lost by poor handling of nuclear fuel and the records pertaining to fuel inventory. Nuclear material management requires the maintaining of complete and informative records by the power reactor operator. These records need not be complex to satisfy the criteria of completeness and adequacy. In fact, simplicity is extremely desirable. Despite the fact that nuclear fuel is new and completely different to our conventional fuels no mystery should be attached thereto. Nuclear material control as part of nuclear material management is not limited to simple inventory work but it is the basis for a great deal of other activity that is an inherent part of any power reactor operations such as irradiated fuel shipments, reprocessing of spent fuel, with its associated accounting for reclaimed fuel and material produced during reactor operation, and the establishing and maintaining of an adequate

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

    Iov, Florin; Ciobotaru, Mihai; Blaabjerg, Frede

    2008-01-01

    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...... 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 will be 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 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...

  16. New power strategies (the battle for control).

    Solovy, A

    1994-12-20

    When yesterday's home care company has become today's primary care network, and yesterday's purchaser is today's provider, it's no longer enough to look at hospital/physician integration for clues to the new health care road map. Instead, it's vital to examine how all the players in the health care system are interacting, and what the interchanges of power and activity among them mean. In a probing analysis, Contributing Editor Alden Solovy applies an innovative macroeconomic theory to the radical reshaping of health care now taking place. PMID:7994300

  17. Autonomous Control Capabilities for Space Reactor Power Systems

    Wood, Richard T.; Neal, John S.; Brittain, C. Ray; Mullens, James A.

    2004-02-01

    The National Aeronautics and Space Administration's (NASA's) Project Prometheus, the Nuclear Systems Program, is investigating a possible Jupiter Icy Moons Orbiter (JIMO) mission, which would conduct in-depth studies of three of the moons of Jupiter by using a space reactor power system (SRPS) to provide energy for propulsion and spacecraft power for more than a decade. Terrestrial nuclear power plants rely upon varying degrees of direct human control and interaction for operations and maintenance over a forty to sixty year lifetime. In contrast, an SRPS is intended to provide continuous, remote, unattended operation for up to fifteen years with no maintenance. Uncertainties, rare events, degradation, and communications delays with Earth are challenges that SRPS control must accommodate. Autonomous control is needed to address these challenges and optimize the reactor control design. In this paper, we describe an autonomous control concept for generic SRPS designs. The formulation of an autonomous control concept, which includes identification of high-level functional requirements and generation of a research and development plan for enabling technologies, is among the technical activities that are being conducted under the U.S. Department of Energy's Space Reactor Technology Program in support of the NASA's Project Prometheus. The findings from this program are intended to contribute to the successful realization of the JIMO mission.

  18. Controlling the Fluctuations of Wind Power By SMES Using Optimized Coil Size

    Ankur Saini

    2014-09-01

    Full Text Available The hybrid power system that solely depends on the intermittent renewable energy sources will generate a fluctuating output power that leads to damage to the machines that operates on a stable supply. Therefore, an energy storage system Super Conducting Magnetic Energy Storage (SMES is introduced with function to reduce the output power fluctuation problems. SMES systems are efficient devices of storing large electrical energy but they are quite costly. Thus this paper suggests an Optimization method of optimizing the controller parameters, SMES current and Coil Size of the SMES thereby controls the power fluctuation. In controller PI controller is used to control Active and Reactive power of the Tie-line. Based on the minimization of variance active and reactive power fluctuation is reduced. The controller parameters, Coil Size and Initial SMES current are tuned by Particle Swarm Optimization and compared the results by Genetic Algorithm. This optimization and Controller model is realized by using MATLAB.

  19. Cross-Layer Cooperative Power Control in Heterogeneous Multihop Networks

    Feng Tian; Dapeng Li; Xuejun Zhang; Zhen Yang

    2016-01-01

    This paper investigates how to perform optimal cooperative power control for the coexistence of heterogeneous multihop networks. Although power control on the node level in multihop networks is a difficult problem due to its large design space and the coupling relationship of power control with scheduling and routing, we formulate a multiobjective optimization problem for the total power consumption of the two heterogeneous multihop networks with discretized power level. We reformulate the no...

  20. Adaptive feedback active noise control

    Kuo, Sen M.; Vijayan, Dipa

    Feedforward active noise control (ANC) systems use a reference sensor that senses a reference input to the controller. This signal is assumed to be unaffected by the secondary source and is a good measure of the undesired noise to be cancelled by the system. The reference sensor may be acoustic (e.g., microphone) or non-acoustic (e.g., tachometer, optical transducer). An obvious problem when using acoustic sensors is that the reference signal may be corrupted by the canceling signal generated by the secondary source. This problem is known as acoustic feedback. One way of avoiding this is by using a feedback active noise control (FANC) system which dispenses with the reference sensor. The FANC technique originally proposed by Olson and May employs a high gain negative feedback amplifier. This system suffered from the drawback that the error microphone had to be placed very close to the loudspeaker. The operation of the system was restricted to low frequency range and suffered from instability due to the possibility of positive feedback. Feedback systems employing adaptive filtering techniques for active noise control were developed. This paper presents the FANC system modeled as an adaptive prediction scheme.

  1. BWR startup and shutdown activity transport control

    This paper summarizes BWR industry experience on good practices for controlling the transport of corrosion product activity during shutdowns, particularly refueling outages, and for startup chemistry control to minimize IGSCC (intergranular stress corrosion cracking). For shutdown, overall goals are to minimize adverse impacts of crud bursts and the time required to remove activated corrosion products from the reactor coolant during the shutdown process prior to refueling, and to assist plants in predicting and controlling radiation exposure during outages. For startup, the overall goals are to highlight conditions during early heatup and startup when sources of reactor coolant oxidants are high, when there is a greater likelihood for chemical excursions associated with refueling outage work activities, and when hydrogen injection is not available to mitigate IGSCC due to system design limitations. BWR water chemistry has changed significantly in recent years with the adoption of hydrogen water chemistry, zinc addition and noble metal chemical applications. These processes have, in some instances, resulted in significant activity increases during shutdown evolutions, which together with reduced time for cleanup because of shorter outages, has consequently increased outage radiation exposure. A review several recent outages shows that adverse effects from these conditions can be minimized, leading to the set of good practice recommendations for shutdown chemistry control. Most plants lose the majority of their hydrogen availability hours during early startup because feedwater hydrogen injection systems were not originally designed to inject hydrogen below 20% power. Hydrogen availability has improved through modifications to inject hydrogen at lower power levels, some near 5%. However, data indicate that IGSCC is accelerated during early startup, when dissolved oxygen and hydrogen peroxide levels are high and reactor coolant temperatures are in the 300 to 400 oF (

  2. Schedule control in Ling Ao nuclear power project

    Ling Ao Nuclear Power Station (LANP) is first one built up by self-reliance in China with power capacity 990x2 MWe. The results of quality control, schedule control and cost control are satisfactory. The commercial operation days of Unit 1 and Unit 2 were 28th May 2002 and 8th Jan. 2003 respectively, which were 48 days and 66 days in advance of the project schedule. This paper presents the practices of self-reliance schedule control system in LANP. The paper includes 10 sections: schedule control system; targets of schedule control; schedule control at early stage of project; construction schedule; scheduling practice; Point curves; schedule control of design and procurement; a good practice of construction schedule control on site; commissioning and startup schedule; schedule control culture. Three figures are attached. The main contents of the self-reliance schedule control system are as follows: to draw up reasonable schedules and targets; to setup management mechanism and procedures; to organize powerful project management team; to establish close monitoring system; to provide timely progress reports and statistics information. Five kinds of schedule control targets are introduced, i.e. bar-chart schedule; milesones; Point curves; interface management; hydraulic test schedule of auxiliary piping loops; EMR/EMC/EESR issuance schedules. Six levels of bar-chart schedules were adopted in LANP, but the bar-chart schedules were not satisfactory for complicated erection condition on site, even using six levels of schedules. So a kind of Point curves was developed and their advantages are explained. Scheduling method of three elements: activity, duration, logic, which was adopted in LANP, is introduced. The duration of each piping activities in LANP level 2 project schedule was calculated based on the relevant working Point quantities. The analysis and adjustment of Point curves are illustrated, i.e. balance of monthly quantities; possible production in the peakload

  3. Control system for a nuclear power producing unit

    The invention deals with an improvement of a power/load control system for a PWR type reactor. A signal that regulates the feedwater supply is in proportion to the desired power of the reactor. Arrangements for the control of the heat transfer from the reactor and the control of the feedwater flow rate to the steam generator are both simultaneously affected by the feedwater supply signal. This coordinated control system embodies a fast response of power generation to power demand

  4. Monitoring Biological Activity at Geothermal Power Plants

    Peter Pryfogle

    2005-09-01

    The economic impact of microbial growth in geothermal power plants has been estimated to be as high as $500,000 annually for a 100 MWe plant. Many methods are available to monitor biological activity at these facilities; however, very few plants have any on-line monitoring program in place. Metal coupon, selective culturing (MPN), total organic carbon (TOC), adenosine triphosphate (ATP), respirometry, phospholipid fatty acid (PLFA), and denaturing gradient gel electrophoresis (DGGE) characterizations have been conducted using water samples collected from geothermal plants located in California and Utah. In addition, the on-line performance of a commercial electrochemical monitor, the BIoGEORGE?, has been evaluated during extended deployments at geothermal facilities. This report provides a review of these techniques, presents data on their application from laboratory and field studies, and discusses their value in characterizing and monitoring biological activities at geothermal power plants.

  5. Harmonics Mitigation Using Active Power Filter

    Sourabh Gupta

    2013-06-01

    Full Text Available This paper is proposed to reconsider the development of active power filter (APF technologies that are routinely utilized to mitigate harmonics in utility power lines. This reconsider can furthermore be considered as a “tutorial-type paper” as it provides a holistic coverage of the APF technologies by omitting the tedious details, but without losing the major essence of the subject matter. It is wanted that by this approach, it would be likely to lure more power engineering readers to be involved in this important and growing area. The discussion starts with a short overview of harmonic distortion difficulties and their impacts on electric power and powered value. The operation of common APF topologies, namely the shunt, sequence and hybrid APFs are recounted in minutia. This is followed by a reconsider on different types of reference pointer estimation extraction methods. In specific, the application of the p-q and elongation p-q theorems to extract the quotation pointers are elaborated, as they are the most commonly discovered in practical APF systems eventually, an overview of the APF command schemes is provided. A short consideration on the APF-solar photovoltaic scheme is furthermore granted. At the end of the paper, important references are cited to aid readers who are interested to discover the subject in larger detail.

  6. Introducing Model Predictive Control for Improving Power Plant Portfolio Performance

    Edlund, Kristian Skjoldborg; Bendtsen, Jan Dimon; Børresen, Simon;

    2008-01-01

    This paper introduces a model predictive control (MPC) approach for construction of a controller for balancing the power generation against consumption in a power system. The objective of the controller is to coordinate a portfolio consisting of multiple power plant units in the effort to perform...

  7. An identification of active power imbalance using wavelet transform

    Avdakovic, S.; Music, M. [Public Enterprise Elektroprivreda of Bosnia and Herzegovina, Sarajevo (Bosnia and Herzegowina). Dept. for Development; Nuhanovic, A.; Kusljugic, M. [Tuzla Univ., Tuzla (Bosnia and Herzegowina). Faculty of Electrical Engineering, Dept. of Power Systems Analysis

    2009-07-01

    Wavelet transformations were used to identify and estimate an active power imbalance as part of a wide area monitoring protection and control (WAMPC) system. A quantitative analysis of the effect of a small load change was presented in order to demonstrate the method. The study showed that the impact of a sudden active power imbalance was shared among generators during power system responses according to various criteria before arriving at a new steady state condition. The impact was followed by oscillatory power swings. The qualitative analysis demonstrated that immediately after the onset of the power imbalance, machines shared the impact according to their electric proximity to the point of impact. After a transient period, the machines shared the same impact according to different criteria. Wavelet transform was then used to estimate the frequency of the center of inertia as well as the impact of the imbalance on the machines. A 2-area test system was simulated in order to demonstrate the method. It was concluded that wavelet transform can be used to accurately detect and estimate active power imbalances. 9 refs., 4 tabs., 7 figs.

  8. Real-Time Implementation of Type-2 FLC-Based Shunt Active Filter Control Strategies (p-q and Id-Iq) with Different Fuzzy MFs for Power Quality Improvement

    Mikkili, Suresh; Panda, Anup Kumar

    2014-06-01

    This research article proposes the shunt active filter (SHAF) control strategies (p-q and Id-Iq), which are used to improve the power quality of the electrical network by mitigating the harmonics with the help of Type-2 fuzzy logic controller (Type-2 FLC) different membership functions (MFs). Three-phase reference current waveforms generated by proposed scheme are tracked by the three-phase voltage source converter in a hysteresis band control scheme. The performance of the proposed control strategies has been evaluated in terms of harmonic mitigation and DC link voltage regulation under various source conditions. In order to maintain DC link voltage constant and to generate the compensating reference currents, we have developed Type-2 FLC with different fuzzy MFs (trapezoidal, triangular and Gaussian). The SHAF with proposed Type-2 FLC using Gaussian MF is able to eliminate the uncertainty in the system and SHAF gains outstanding compensation abilities. The detailed real-time results using real-time digital simulator are presented to support the feasibility of proposed control strategies.

  9. Programmable controller for the power station environment

    A programmable controller has been developed specifically to meet the needs of a large power station. Designed to be used in large numbers throughout the station, each controller replaces one separately fused relay logic circuit controlling one or several devices in a process or electrical logic system. A number of built-in diagnostic features have been provided to reduce substantially the cost of detecting and locating field wiring faults such as discontinuities and ground faults. The mechanical and electrical design has been arranged to minimize the installation and maintenance costs through such features as factory pre-assembled field connectors, a compact mechanical arrangement, a small number of standard replaceable modules, and the mounting of all failure-prone components on the modules as opposed to the motherboard or crate. Production prototype units have been tested for their capability of withstanding the environmental effects of temperature, transient interference, RFI and seismic vibration. A pre-production pilot run is underway leading to the installation of large numbers of units in a nuclear station. 7 refs

  10. Instrumentation control system in nuclear power plant

    Purpose: To improve the reliability of instrumentation control system in a nuclear power plant by using an optical fiber cable as a transmission path between a multiplexer and a central control room to thereby eliminate noises resulted from electromagnetic inductions or the likes. Constitution: Signals from neutron detectors are sent by way of ceramic-insulated cables to pre-amplifiers disposed outside of the pressure vessel of a nuclear reactor, converted into voltage pulse signals and then sent by way of coaxial cables to a multiplexer. The multiplexer receives a plurality of voltage pulse signals corresponding to the neutron detectors respectively, converts them into a time-shared electric signal train and sends it to an optical pulse transmitter. The transmitter converts the supplied signals into an optical pulse signal train corresponding to the electric signal train from the multiplexer and sends it by way of an optical fiber cable to an optical pulse receiver disposed in a central control room. (Kawakami, Y.)

  11. Information presentation in power plant control rooms

    The objective of this study is to support operators' work especially in the control rooms of power plant. The exemplified process is a pressurized water (nuclear) reactor (PWR). The man-process interface is an information system that covers information refining, information presentation, information system handling, and process control. THe emphasis in this study is on the organization and presentation of information and on the alert function that is part of the information system. Another goal is to design the alert function so as to radically reduce the number of alarms during plant shutdown, e.g. during the refuelling or maintenance period and during a disturbance. Further, the experimental validation of CFMS (Critical Function Monitoring System), developed by Combustion Engineering, Inc. in the U.S.A. is described briefly. The validation was made at the Loviisa training simulator in the autumn of 1982. CFMS is a safety-related functional alarm system. The functional decomposition of information has turned out to be successful and it is helpful in designing displays. Preliminary criteria for designing displays, the structure of the information presentation system and the illustration of main interactions are presented. General practical ideas on designing the alert function seem very promising. Preliminary results of the CFMS validation are presented. Further, some ideas are presented on how to carry out the analysis and how to make such validations in the future. A new idea for the evaluation of core safety is presented, based on control theory concepts

  12. Control technology for nuclear power system of next generation

    This report is the summary of the results obtained by the investigation activities for two years carried out by the expert committee on investigation of control technology for nuclear power system of next generation. The course of investigation is outlined, and as the results, as advanced control technologies, adaptive control. H sub (infinite) control, fuzzy control and the application of autonomous distributed system and genetic algorithm to control; as operation support technology, the operation and monitoring system for nuclear power plants and safety support system; as interface technology which is the basic technology of them, virtual reality, multimedia and so on; further, various problems due to human factors, computer technology, artificial intelligence and others were taken up, and the grasp of the present status and the future subjects was carried out, including the information in international conferences. The items of the investigation are roughly divided into measurement and control technologies, interface technology and operation support, human factors, computer technology and artificial intelligence, and the trend in foreign countries, and the results of investigation for respective items are reported. (K.I.)

  13. Power Quality Improvement in Distribution System using ANN Based Shunt Active Power Filter

    Somlal Jarupula

    2015-02-01

    Full Text Available This paper focuses on an Artificial Neural Network (ANN controller based Shunt Active Power Filter (SAPF for mitigating the harmonics of the distribution system. To increase the performance of the conventional controller and take advantage of smart controllers, a feed forward-type (trained by a back propagation algorithm ANN-based technique is implemented in shunt active power filters for producing the controlled pulses required for IGBT inverter. The proposed approach mainly work on the principle of capacitor energy to maintain the DC link voltage of a shunt connected filter and thus reduces the transient response time when there is abrupt variation in the load. The entire power system block set model of the proposed scheme has been developed in MATLAB environment. Simulations are carried out by using MATLAB, it is noticed that the %THD is reduced to 2.27% from 29.71% by ANN controlled filter. The simulated experimental results also show that the novel control method is not only easy to be computed and implemented, but also very successful in reducing harmonics.  

  14. Power-based control with integral action for wind turbines connected to the grid

    Peña, R. R.; Fernández, R. D.; Mantz, R. J.; Battaiotto, P. E.

    2015-10-01

    In this paper, a power shaping control with integral action is employed to control active and reactive powers of wind turbines connected to the grid. As it is well known, power shaping allows finding a Lyapunov function which ensures stability. In contrast to other passivity-based control theories, the power shaping controller design allows to use easily measurable variables, such as voltages and currents which simplify the physical interpretation and, therefore, the controller synthesis. The strategy proposed is evaluated in the context of severe operating conditions, such as abrupt changes in the wind speed and voltage drops.

  15. Managing Siting Activities for Nuclear Power Plants

    One of the IAEA's statutory objectives is to ''seek to accelerate and enlarge the contribution of atomic energy to peace, health and prosperity throughout the world''. One way this objective is achieved is through the publication of a range of technical series. Two of these are the IAEA Nuclear Energy Series and the IAEA Safety Standards Series. According to Article III.A.6 of the IAEA Statute, the safety standards establish 'standards of safety for protection of health and minimization of danger to life and property.' The safety standards include the Safety Fundamentals, Safety Requirements and Safety Guides. These standards are written primarily in a regulatory style, and are binding on the IAEA for its own programmes. The principal users are the regulatory bodies in Member States and other national authorities. The IAEA Nuclear Energy Series comprises reports designed to encourage and assist R and D on, and application of, nuclear energy for peaceful uses. This includes practical examples to be used by owners and operators of utilities in Member States, implementing organizations, academia, and government officials, among others. This information is presented in guides, reports on technology status and advances, and best practices for peaceful uses of nuclear energy based on inputs from international experts. The IAEA Nuclear Energy Series complements the IAEA Safety Standards Series. The introduction of nuclear power brings new challenges to States - one of them being the selection of appropriates sites. It is a project that needs to begin early, be well managed, and deploy good communications with all stakeholders; including regulators. This is important, not just for those States introducing nuclear power for the first time, but for any State looking to build a new nuclear power plant. The purpose of the siting activities goes beyond choosing a suitable site and acquiring a licence. A large part of the project is about producing and maintaining a validated

  16. One solution of main controller in thermal power plants

    Radmilović Nebojša

    2008-01-01

    Full Text Available This paper describes functionality between pressure regulation of steam boiler and electrical power regulation of turbine-generator system at thermal power plants. Importans of this control is essentially in coordinate work mode when these complex and non-linear systems have to work as one integrated entity with tendency to produce electrical power at optimal and stable way. Steam generator - boiler is system with long transport delay and here is recommendation for improving pressure regulation. This regulation realized at thermal power plant nominal power 308MW and given working results in real time. Index Terms - boiler control, combustion control, thermal power plants, PID controller.

  17. Probabilistic Analysis of an Automatic Power Factor Controller with variation in Power Factor

    P K Bhatia; ROOSEL JAIN; GULSHAN TANEJA,

    2012-01-01

    In the present study, the probabilistic analysis of an automatic power factor controller (APFC) system working in industry/factory is investigated. The power factor correction of electrical loads and energy losses due to poor power factor are the problems common to all industrial companies. Therefore, the study of APFC unit is of greatimportance. Initially, the system is operative with controlled power factor. Then it may transit to state with power factor not controlled. On the failure of th...

  18. Communications and control for electric power systems

    Kirkham, H.; Goettsche, A.; Niebur, D.; Friend, H.; Johnston, A.

    1991-01-01

    The first section of the report describes the AbNET system, a hardware and software communications system designed for distribution automation (it can also find application in substation monitoring and control). The topology of the power system fixes the topology of the communications network, which can therefore be expected to include a larger number of branch points, tap points, and interconnections. These features make this communications network unlike any other. The network operating software has to solve the problem of communicating to all the nodes of a very complex network in as reliable a way as possible even if the network is damaged, and it has to do so with minimum transmission delays and at minimum cost. The design of the operating protocols is described within the framework of the seven-layer Open System Interconnection hierarchy of the International Standards Organization. Section 2 of the report describes the development and testing of a high voltage sensor based on an electro-optic polymer. The theory of operation is reviewed. Bulk fabrication of the polymer is discussed, as well as results of testing of the electro-optic coefficient of the material. Fabrication of a complete prototype sensor suitable for use in the range 1-20 kV is described. The electro-optic polymer is shown to be an important material for fiber optic sensing applications. Appendix A is theoretical support for this work. The third section of the report presents the application of an artificial neural network, Kohonen's self-organizing feature map, for the classification of power system states. This classifier maps vectors of an N-dimensional space to a 2-dimensional neural net in a nonlinear way preserving the topological order of the input vectors. These mappings are studied using a nonlinear power system model.

  19. The Paralleling of High Power High Frequency Amplifier Based on Synchronous and Asynchronous Control

    程荣仓; 刘正之

    2004-01-01

    The vertical position of plasma in the HT-7U Tokamak is inherently unstable. In order to realize active stabilization, the response rate of the high-power high-frequency amplifier feeding the active control coils must be fast enough. This paper analyzes the paralleling scheme of the power amplifier through two kinds of control mode. One is the synchronous control; the other is the asynchronous control. Via the comparison of the two kinds of control mode, both of their characteristics are given in the text. At last, the analyzed result is verified by a small power experiment.

  20. Research on the optimal control method for normally closed loop distribution power flow with dual sources based on the minimization of series compensated active power%基于串补有功最小的双电源配电环网潮流优化控制策略的研究

    仉志华; 徐丙垠; 陈青; 冯晨星

    2012-01-01

    双电源配电环网是实现配电网故障无缝自愈进而有效解决短时停电问题的基础,但配电环网中潮流呈自然分布且缺乏有效的调节手段.利用统一潮流控制器(UPFC)对双电源配电环网潮流控制方法进行研究.基于配电环网潮流分布与潮流控制规律,以负荷节点电压偏移与合环馈线功率输出极限为约束条件,推导出在功率调节量一定时UPFC输出有功功率最小的潮流优化控制策略.该方法能够在满足潮流灵活调节的前提下保证UPFC应用的经济性.针对两端出力不均的情况建立了双电源配电环网仿真模型,仿真结果证明了该方法的有效性.%The closed loop distribution network of double sources is the basis of realizing the seamless fault self-healing of distribution network fault, but the power flow has the characteristic of natural distribution and is lack of effective control means. We adopt united power flow controller (UPFC) to research the power flow control methods. Based on analyzing the power flow distribution and control regularity with the normally closed loop distribution, and taking the load node voltage deviation and closed loop feeder power output limit as constraints, we deduce the optimal power flow control scheme in the condition of minimum active power output by UPFC when the power regulation variables are fixed. The control method can ensure the economy of UPFC application while meeting the flexible regulation of power flow. Considering the issue of unequal output at two sides, we establish a simulation model for the closed loop distribution network of double sources. Simulation results show that the method is effective.

  1. A Control Strategy for Single-phase Grid-Connected Inverter with Power Quality Regulatory Function

    Luo Ling; Chen Tiantian; Jin Jiapei; Su Shaoze

    2013-01-01

    A single-phase grid-connected inverter system based on LCL filter is established,which combines the features of inverter and active power filter. A composite control strategy for grid-connected inverter with the function of implementing reactive power compensation and harmonic compensation in the grid-connected power generation is proposed. Firstly, grid-connected inverter system structure and model is analyzed. A quasi-Proportional Resonant control method to gain the control of grid-connecte...

  2. Power electronics and control for wind power systems

    Iov, Florin; Blaabjerg, Frede

    2009-01-01

    The global electrical energy consumption is still rising and there is a steady demand to increase the power capacity. It is expected that it has to be doubled within 20 years. The production, distribution and use of the energy should be as technological efficient as possible and incentives to sav...... renewable energy sources, wind energy, which by means of power electronics are changing from being minor energy sources to be acting as important power sources in the electrical network....... energy at the end-user should be set up. Deregulation of energy has lowered the investment in larger power plants, which means the need for new electrical power sources may be increased in the near future. Two major technologies will play important roles to solve the future problems. One is to change...... the electrical power production 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 the most emerging...

  3. Active control of the noise

    The problems of acoustic noise are more and more preponderant in the measure in that the amount of equipment and industrial machinery is increased such as fans, transformers, compressors etc. the use of devices passive mechanics for the reduction of the noise is effective and very appreciated because its effects embrace a wide range of acoustic frequency. However, to low frequencies, such devices become too big and expensive besides that present a tendency to do not effective. The control of active noise, CAN, using the electronic generation anti-noise, constitutes an interesting solution to the problem because their operation principle allows achieving an appreciable reduction of the noise by means of the use of compact devices. The traditional techniques for the control of acoustic noise like barriers and silenced to attenuate it, are classified as passive and their works has been accepted as norm as for the treatment of problems of noise it refers. Such techniques are considered in general very effective in the attenuation of noise of wide band. However, for low frequency, the required passive structures are too big and expensive; also, their effectiveness diminishes flagrantly, that which makes them impractical in many applications. The active suppression is profiled like a practical alternative for the reduction of acoustic noise. The idea in the active treatment of the noise it contemplates the use of a device electro-acoustic, like a speaker for example that it cancels to the noise by the generation of sounds of Same width and of contrary phase (anti-noise). The cancellation phenomenon is carried out when the ant-noise combines acoustically with the noise, what is in the cancellation of both sounds. The effectiveness of the cancellation of the primary source of noise depends on the precision with which the width and the phase of the generated ant-noise are controlled. The active control of noise, ANC (activates noise control), it is being investigated for

  4. 14 CFR 27.695 - Power boost and power-operated control system.

    2010-01-01

    ... system. 27.695 Section 27.695 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... Systems § 27.695 Power boost and power-operated control system. (a) If a power boost or power-operated control system is used, an alternate system must be immediately available that allows continued...

  5. 14 CFR 29.695 - Power boost and power-operated control system.

    2010-01-01

    ... system. 29.695 Section 29.695 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... Systems § 29.695 Power boost and power-operated control system. (a) If a power boost or power-operated control system is used, an alternate system must be immediately available that allows continued...

  6. New hybrid active power filter for harmonic current suppression and reactive power compensation

    Biricik, Samet; Cemal Ozerdem, Ozgur; Redif, Soydan; Sezai Dincer, Mustafa

    2016-08-01

    In the case of undistorted and balanced grid voltages, low ratio shunt active power filters (APFs) can give unity power factors and achieve current harmonic cancellation. However, this is not possible when source voltages are distorted and unbalanced. In this study, the cost-effective hybrid active power filter (HAPF) topology for satisfying the requirements of harmonic current suppression and non-active power compensation for industry is presented. An effective strategy is developed to observe the effect of the placement of power capacitors and LC filters with the shunt APF. A new method for alleviating the negative effects of a nonideal grid voltage is proposed that uses a self-tuning filter algorithm with instantaneous reactive power theory. The real-time control of the studied system was achieved with a field-programmable gate array (FPGA) architecture, which was developed using the OPAL-RT system. The performance result of the proposed HAPF system is tested and presented under nonideal supply voltage conditions.

  7. Fuzzy Logic Controller for Automatic Nuclear Power Plant

    Reactor output power stabilization is the desired goal for any reactor. During the operation of the reactor, different changes in its operating conditions occur.Therefore, an automatic reactor power control is required to compensate the reactivity changes. To achieve the optimal stabilization of reactor output power, Proportional-Integral-Derivative (PID) and Fuzzy Logic Controller (FLC) approaches are developed. Evaluation of each approach is discussed. A developed reactor power plant model is suggested to analyze and compare PID and FLC controller approaches. The simulation results show that FLC controller is a good approach for automatic reactor output power control

  8. Power balance control using evolutionary algorithm

    This paper described a nonlinear optimization problem to enable independent system operators (ISOs) to make least-cost decisions for the activation of ancillary services. A self-organizing migration algorithm (SOMA) based on the competitive-cooperative behavior of intelligent creatures solving a common problem was tested on 2 scenarios based on real values obtained from a transmission system operator (TSO) in the Czech Republic. The 6 hour datasets were used to demonstrate the prediction of error between production and consumption. The characteristics and capacity of the ancillary services were used as system and operating constraints for the optimization. History values from the datasets were then simulated. The SOMA algorithm then searched for solutions to minimize the cost function. Scenarios for a short and long outage of a large generating unit were used to demonstrate the algorithm's ability to balance power in the system. 4 refs., 1 tab., 3 figs.

  9. POWER QUALITY CONTROL IN A WIND POWER GENERATING SYSTEM USING SVPWM CONTROLLED UNIFIED POWER QUALITY CONDITIONER WITH GENETIC ALGORITHM

    P.SARAVANAN

    2013-06-01

    Full Text Available Renewable energy resources (RES are being increasingly connected in distribution systems utilizing power electronic converters.This paper proposes a novel control design for achieving maximum benefits from the grid-interfacing inverters when installed in 3-phase 3-wire distribution systems. The main aim of the proposed system is to compensate current unbalance, load current harmonics, load reactive power demand and load neutral current. Modulation technique used is Space Vector Pulse Width Modulation (SVPWM. Simulation and experimental studies on a three phase 3 wire distribution system is used to verify the performance and real time implementation of the control design.

  10. Power supply control system of SDUV-FEL test facility

    Background: The power supply control system of Shanghai Deep Ultra-Violet Free Electron Laser (SDUV-FEL) test facility is an Ethernet-based distributed control system developed and integrated using the Experimental Physics and Industrial Control System (EPICS) toolkit. Purpose: The SDUV-FEL test facility has been integrated to test new FEL principles. Methods: The power supply control system provides control scheme for direct I/O controlled analog power supply, full digital-controlled power supply and Agilent commercial power supply with GPIB interface. Embedded I/O controller, runtime database and graphic operation interface are applied in this system. Results: The high performance of system demonstrated that the SASE and seeded FEL experiments were carried out in the past years. Conclusions: The power supply control system of the SDUV-FEL test facility has achieved long-term stable running, which is useful for future similar facility. (authors)

  11. Automatic power control for a pressurized water reactor

    During a normal operation of a pressurized water reactor (PWR), the reactivity is controlled by control rods, boron, and the average temperature of the primary coolant. Especially in load follow operation, the reactivity change is induced by changes in power level and effects of xenon concentration. The control of the core power distribution is concerned, mainly, with the axial power distribution which depends on insertion and withdrawal of the control rods resulting in additional reactivity compensation. The utilization of part strength control element assemblies (PSCEAs) is quite appropriate for a control of the power distribution in the case of Yonggwang Nuclear Unit 3 (YGN Unit 3). However, control of the PSCEAs is not automatic, and changes in the boron concentration by dilution/boration are done manually. Thus, manual control of the PSCEAs and the boron concentration require the operator's experience and knowledge for a successful load follow operation. In this thesis, the new concepts have been proposed to adapt for an automatic power control in a PWR. One of the new concepts is the mode K control, another is a fuzzy power control. The system in mode K control implements a heavy-worth bank dedicated to axial shape control, independent of the existing regulating banks. The heavy bank provides a monotonic relationship between its motion and the axial power shape change, which allows automatic control of the axial power distribution. And the mode K enables precise regulation, by using double closed-loop control of the reactor coolant temperature and the axial power difference. Automatic reactor power control permits the nuclear power plant to accommodate the load follow operations, including frequency control, to respond to the grid requirements. The mode K reactor control concepts were tested using simulation responses of a Korean standardized 1000-MWe PWR which is a reference plant for the YGN Unit 3. The simulation results illustrate that the mode K would be

  12. Wind Power Plant Control - An Overview

    Altin, Müfit; Teodorescu, Remus; Bak-Jensen, Birgitte; RODRIGUEZ, Pedro; Iov, Florin; Kjær, Philip C.

    2010-01-01

    Recent developments in wind turbine technology go towards installation of larger Wind Power Plants (WPPs). Therefore, power system operators have been challenged by the WPP penetration impacts in order to maintain reliabillity and stability of the power system. The revised grid codes have concentrated on the WPP connection point and as a result a WPP is considered as a single power plant. Nevertheless, compared to conventional power plants, WPPs have different inherent features such as conver...

  13. Solar Power Station Output Inverter Control Design

    J. Bauer

    2011-04-01

    Full Text Available The photovoltaic applications spreads in these days fast, therefore they also undergo great development. Because the amount of the energy obtained from the panel depends on the surrounding conditions, as intensity of the sun exposure or the temperature of the solar array, the converter must be connected to the panel output. The Solar system equipped with inverter can supply small loads like notebooks, mobile chargers etc. in the places where the supplying network is not present. Or the system can be used as a generator and it shall deliver energy to the supply network. Each type of the application has different requirements on the converter and its control algorithm. But for all of them the one thing is common – the maximal efficiency. The paper focuses on design and simulation of the low power inverter that acts as output part of the whole converter. In the paper the design of the control algorithm of the inverter for both types of inverter application – for islanding mode and for operation on the supply grid – is discussed. Attention is also paid to the design of the output filter that should reduce negative side effects of the converter on the supply network.

  14. Soft-Starting Power-Factor Motor Controller

    Nola, F. J.

    1983-01-01

    Three-phase power-factor controller with soft start is based on earlier version that does not control starting transients. Additional components serve to turn off "run" command signal and substitute gradual startup command signal during preset startup interval. Improved controller reduces large current surge that usually accompanies starting. Controller applies power smoothly, without causing motor vibrations.

  15. Power spectra of active galactic nuclei

    2009-01-01

    The power spectral densities(PSDs)for a sample of active galactic nuclei(AGNs)are analyzed in both the frequency domain and the time domain.We find for each object that for broadband noise a character timescale-bifurcation timescale of Fourier and time-domain PSD exists in the 10 3 -10 6 s range, below which the time-domain power spectrum is systematically higher than the corresponding Fourier spectrum.The relationship between bifurcation timescale,AGN mass and luminosity is studied.Compared with the fact that similar phenomena have been found for Galactic black hole candidates(GBHs) with bifurcation timescale~0.1 s but not for accreting neutron stars,our finding indicates that AGNs and GBHs have common intrinsic nature in rapid X-ray variability with a character time parameter scaled with their masses.

  16. Power spectra of active galactic nuclei

    WANG TaiShan; WU YuXiang; LIU Yuan

    2009-01-01

    The power spectral densities (PSDs) for a sample of active galactic nuclei (AGNs) are analyzed in both the frequency domain and the time domain. We find for each object that for broadband noise a character timescale-bifurcation timescale of Fourier and time-domain PSD exists in the 103-106 s range,below which the time-domain power spectrum is systematically higher than the corresponding Fourier spectrum. The relationship between bifurcation timescale, AGN mass and luminosity is studied. Compared with the fact that similar phenomena have been found for Galactic black hole candidates (GBHs)with bifurcation timescale ~0.1 s but not for accreting neutron stars, our finding indicates that AGNs and GBHs have common intrinsic nature in rapid X-ray variability with a character time parameter scaled with their masses.

  17. Assessment of PCDD/F and PBDD/F Emissions from Coal-fired Power Plants during Injection of Brominated Activated Carbon for Mercury Control

    The effect of the injection of brominated powdered activated carbon (Br-PAC) on the emission of brominated and chlorinated dioxins and furans in coal combustion flue gas has been evaluated. The tests were performed at two U.S. Department of Energy (DOE) demonstration sites where ...

  18. A Digital Controller for Active Aeroelastic Controls

    Ueda, Tetsuhiko; MUROTA, Katsuichi; 上田, 哲彦; 室田, 勝一

    1989-01-01

    A high-speed digital controller for aeroelastic controls was designed and made. The purpose was to minimize adverse phase lag which is inevitably produced by the CPU time of digital processing. The delay deteriorates control performances on rather rapid phenomena like aircraft flutter. With fix-point operation the controller realized 417 microseconds of throughput time including the A/D and D/A conversion. This corresponds to a high sampling rate of 2.4kHz. The controller furnishes two channe...

  19. Nuclear power plant control and instrumentation 1993. Working material

    The regular meeting of the International Working Group on Nuclear Power Plant Control and Instrumentation (IWG-NPPCI) was organized in order to summarize operating experience of nuclear power plant control systems, gain a general overview of activities in development of modern control systems and receive recommendations on the further directions and particular measures within the Agency's programme. The meeting was held at the Merlin-Gerin Headquarters in Paris and was attended by twenty one national delegates and observers from 17 countries. The present volume contains: (1) report on the meeting of the IWG-NPPCI, Paris, 21-22 October 1993, (2) report by the scientific secretary on the major activities of IAEA during 1991-1993 in the NPPCI area, and (3) reports of the national representatives to the International Working Group on NPPCI. The papers and discussions with practical experience and described actual problems encountered. Emphasis was placed on the technical, industrial and economic aspects of the introduction of modern control systems and on the improvement of plant availability and safety. Refs, figs and tabs

  20. Reactivity control rod for controlling reactor power distribution

    Since a cladding tube is situated at the outer side, it undergoes neutron irradiation in a reactor core and also undergoes compression force due to high pressure of reactor coolants to cause a creep phenomenon, and the diameter is reduced as it is used. Then, neutron absorbing rods as reactivity control rods for controlling the power distribution are constituted with a cladding tube, a spacer tube disposed at the central portion of the cladding tube and a borosilicate glass tube disposed between the cladding tube and the spacer tube. The gap between the borosilicate glass tube and the spacer tube is gradually changed so that the inner diameter of the borosilicate glass is increased as it comes closer to the lower end plug. The time of contact between the cladding tube and the spacer tube in the inside is delayed by the constitution of the borosilicate glass tube disposed in the cladding tube of the neutron absorbing rod as the reactivity control rod thereby capable of extending the integral working life time with no rupture of the cladding tube. (N.H.)

  1. A performance comparison of DFIG using power transfer matrix and direct power control techniques

    K. Viswanadha S Murthy

    2014-10-01

    Full Text Available This paper presents a direct power control and power transfer matrix model for a doubly-fed induction generator (DFIG wind energy system (WES. Control of DFIG wind turbine system is traditionally based on either stator-flux-oriented or stator-voltage-oriented vector control. The performance of Direct Power Control (DPC and Power transfer Matrix control for the same wind speed are studied. The Power transfer matrix Control gave better results. The validity and performance of the proposed modelling and control approaches are investigated using a study system consisting of a grid connected DFIG WES. The performance of DFIG with Power Transfer Matrix and Direct Power Control (DPC techniques are obtained through simulation. The time domain simulation of the study system using MATLAB Simulink is carried out. The results obtained in the two cases are compared

  2. EVALUATING DEGREE OF ACTIVE POWER LOSSES REDUCTION IN THE ELECTRIC POWER LINES WITH REACTIVE POWER COMPENSATION

    V. N. Radkevich

    2016-01-01

    Full Text Available The paper considers evaluation procedure for the degree of active power losses reduction in the power transmission lines under 1 kV and 6–10 kV of the systems of electric power supply of industrial enterprises with compensating installations mounted at the side of the customer. The capacitor installations conform to the applied voltage level and factor in dielectric losses in the capacitors. The voltage at the compensating device terminal changes from 0.95 to 1.05 of the capacitors nominal voltage. The study did not account for reactive power losses in the line, nor did it for its charge capacity, conditioned by relative shortness of the cable lines generally operating in the mains of industrial enterprises. For this reason, the quantities of reactive power being consumed and generated by the transmission line are negligible and do not significantly affect the reactive power flux. The researchers obtain functional relations that allow estimating the degree of power loss reduction in the transmission line factoring in its explicit initial data. They perform mathematical analysis of the obtained functional relations and study the function by means of derivatives. The function extremum points are found as well as the intervals of its increment and decrement. A graphical research of the obtained functional relation is performed. It is ascertained that reduction of the active power losses is contingent on the line and the capacitor-installation engineering factors, the electrical energy consumer reactive load value as well as the voltage applied to the capacitor installation. The functional relations presented in the article can be employed in scoping calculation necessary for decision making on the reactive power compensation in systems of the industrial facilities electric power supply. Their account will allow a more accurate estimate of technical and economic effect of the capacitor bank installation in the electrical mains under 1 kV and 6

  3. Priority Control Strategy of VSC-MTDC System for Integrating Wind Power

    Wen-ning Yan

    2015-01-01

    Full Text Available For the obvious advantages in integrating wind power, multiterminal HVDC transmission system (VSC-MTDC is widely used. The priority control strategy is proposed in this paper considering the penetration rate of wind power for the AC grid. The strategy aims to solve the problems of power allocation and DC voltage control of the DC system. The main advantage of this strategy is that the demands for wind power of different areas can be satisfied and a power reference for the wind power trade can also be provided when wind farms transmit active power to several AC grids through the DC network. The objective is that power is well distributed according to the output power of wind farm with the demand of AC system and satisfactory control performance of DC voltage is obtained.

  4. Power Control of Wind Turbine Based on Fuzzy Sliding-Mode Control

    Tahir Khalfallah

    2015-02-01

    Full Text Available This paper presents the study of a variable speed wind energy conversion system (WECS using a Wound Field Synchronous Generator (WFSG based on a Fuzzy sliding mode control (FSMC applied to achieve control of active and reactive powers exchanged between the stator of the WFSG and the grid to ensure a Maximum Power Point Tracking (MPPT of a wind energy conversion system. However the principal drawback of the sliding mode, is the chattering effect which characterized by torque ripple, this phenomena is undesirable and harmful for the machines, it generates noises and additional forces of torsion on the machine shaft. A direct fuzzy logic controller is designed and the sliding mode controller is added to compensate the fuzzy approximation errors. The simulation results clearly indicate the effectiveness and validity of the proposed method, in terms of convergence, time and precision.

  5. Testing power system controllers by real-time simulation

    Venne, Philippe; Guillaud, Xavier; Sirois, Frédéric

    2007-01-01

    In this paper, we present a number of state-of-the art methods for testing power system controllers based on the use of a real-time power system simulator. After introducing Hypersim, we list and discuss the different means of connection between the controller under tests and the power system sim...

  6. Evaluation of power control concepts using the PMAD systems test bed. [Power Management and Distribution

    Beach, R. F.; Kimnach, G. L.; Jett, T. A.; Trash, L. M.

    1989-01-01

    The Lewis Research Center's Power Management and Distribution (PMAD) System testbed and its use in the evaluation of control concepts applicable to the NASA Space Station Freedom electric power system (EPS) are described. The facility was constructed to allow testing of control hardware and software in an environment functionally similar to the space station electric power system. Control hardware and software have been developed to allow operation of the testbed power system in a manner similar to a supervisory control and data acquisition (SCADA) system employed by utility power systems for control. The system hardware and software are described.

  7. Quality control of Ling'ao nuclear power station civil construction

    Based on the quality control model adopted during Ling'ao Nuclear Power Station construction, the author briefly introduces quality control process of some main civil construction activities (reinforced concrete, steel liner, steel works and prestressing force) of nuclear power station, and makes some descriptions on non-conformance control of civil works. These quality control processes described come from the concrete practice during civil construction of Ling'ao Nuclear Power Station, and are based on Daya Bay Nuclear Power Station construction experience

  8. Electric power systems analysis and control

    Saccomanno, Fabio

    2003-01-01

    "Highly relevant and timely in scope, the book is essential reading for anyone associated with electric power systems, including students and teachers of power engineering courses, professionals in the industry, consultants, and researchers."--Jacket.

  9. Fact sheet on nuclear power plant instrumentation and control technologies

    Nuclear power plants (NPPs) are facing challenges in several instrumentation and control (I and C) areas with ageing and obsolete components and equipment. With license renewals and power uprates, the long-term operation and maintenance of obsolete I and C systems may not be a cost-effective and reliable option. The effort needed to maintain or increase the reliability and useful life of existing I and C systems may be greater in the long run than modernizing I and C systems or replacing them completely with new digital systems. The increased functionality of the new I and C systems can also open up new possibilities to better support the operation and maintenance activities in the plant. The IAEA recognizes the importance of the profound role the I and C systems play in the reliable, safe, efficient, and cost-effective operations of NPPs by supporting the activities of the Department of Nuclear Energy's Technical Working Group on Nuclear Power Plant Control and Instrumentation (TWG-NPPCI). The group was established in March 1970. Its membership currently includes thirty Member States and three international organizations. The most recent meeting of the TWG-NPPCI was held in May 2005 in Vienna. The meeting report is available at http://www.iaea.org/OurWork/ST/NE/NENP/twg_nppc.html. The next meeting of the TWGNPPCI will be the 21st meeting of the advisory body, and it will be held in May 2007

  10. Centralised power control of wind farm with doubly fed induction generators

    Hansen, A.D.; Sørensen, Poul Ejnar; Iov, F.; Blaabjerg, F.

    2006-01-01

    possibilities for control of different wind farm concepts. The scope of this paper is the control of a wind farm made up exclusively of doubly fed induction generators. The paper addresses the design and implementation issues of such a controller and focuses on the ability of the wind farm control strategy to......At the moment, the control ability of wind farms is a prime research concern for the grid integration of large wind farms, due to their required active role in the power system. This paper describes the on-going work of a research project, whose overall objective is to analyse and assess the...... regulate the wind farm power production to the reference power ordered by the system operators. The presented wind farm control has a hierarchical structure with both a central control level and a local control level. The central wind farm control level controls the power production of the whole farm by...

  11. Centralised power control of wind farm, with doubly fed induction generators

    Hansen, Anca Daniela; Sørensen, Poul; Iov, Florin; Blaabjerg, Frede

    2006-01-01

    possibilities for control of different wind farm concepts. The scope of this paper is the control of a wind farm made up exclusively of doubly fed induction generators. The paper addresses the design and implementation issues of such a controller and focuses on the ability of the wind farm control strategy to......At the moment, the control ability of wind farms is a prime research concern for the grid integration of large wind farms, due to their required active role in the power system. This paper describes the on-going work of a research project, whose overall objective is to analyse and assess the...... regulate the wind farm power production to the reference power ordered by the system operators. The presented wind farm control has a hierarchical structure with both a central control level and a local control level. The central wind farm control level controls the power production of the whole farm by...

  12. Under control. An archeology of nuclear power

    The volume includes a variety of photographs from different German research and power reactors, simulators, the infrastructure of power plants, working situations in the power plant, including fuel exchange and inspection procedures, the dismantling of decommissioned power nuclear facilities and radioactive waste storage facilities. The second part includes interviews with scientists concerning radiobiology, nuclear waste storage, fuel reprocessing, reactor physics, reactor operation, training in the simulator and risk research.

  13. Control strategies based on effective power factor for distributed generation power plants during unbalanced grid voltage

    Camacho Santiago, Antonio; Castilla Fernández, Miguel; Miret Tomàs, Jaume; Matas Alcalá, José; Guzmán Solà, Ramon; de Sousa Pérez, Óscar; Martí Colom, Pau; García de Vicuña Muñoz de la Nava, José Luis

    2013-01-01

    Unbalanced voltages in three-phase power systems is a common perturbation propagated along the grid. Distributed Generation plants have gained widespread attention due to their capability to improve power quality in a distributed manner, including voltage unbalance mitigation. A conventional control strategy to command power plants during balanced grid voltages, is the use of power factor to inject/absorb reactive power depending on grid conditions. Advanced control strategies during unbalanc...

  14. A Low-Power Microcontroller with Accuracy-Controlled Event-Driven Signal Processing Unit for Rare-Event Activity-Sensing IoT Devices

    Daejin Park; Youn, Jonghee M.; Jeonghun Cho

    2015-01-01

    A specially designed microcontroller with event-driven sensor data processing unit (EPU) is proposed to provide energy-efficient sensor data acquisition for Internet of Things (IoT) devices in rare-event human activity sensing applications. Rare-event sensing applications using a remotely installed IoT sensor device have a property of very long event-to-event distance, so that the inaccurate sensor data processing in a certain range of accuracy error is enough to extract appropriate events fr...

  15. Load Frequency Control in Interconnected Power System by Using Classical Controller

    Lusika Roy; Bikash Dey

    2014-01-01

    In modern powers systems change of dynamic load in interconnected power systems is a real life problem in recent era. So to have a constant frequency of operation irrespective of load change in the interconnected power systems, load frequency controllers are employed. To achieve load frequency control, controllers need to maintain a zero steady state errors in multi area interconnected power systems. In this paper we controlled power deviation and frequency deviation of two area interconnecte...

  16. Modeling of the Cloud Interconnected Human Friendly Multi-Agent Based Sustainable Power Controller

    Gricius, G.; Drungilas, D.; Guseinovaitė, J.; Grigaitis, K.; Bielskis, A. A.

    2013-01-01

    The paper presents model of the cloud interconnected multi-agent human friendly sustainable power controller (Controller). The Controller is based on the human ambient comfort affect reward index (ACAR index). The ACAR index depends on human physiological parameters: the temperature, the ECG- electrocardiogram and the EDA-electro-dermal activity. These physiological parameters are used for sustainable power control by multi-agent system developed as the cloud interconnected, instrumented, and...

  17. Optimized Reactive Power Compensation Using Fuzzy Logic Controller

    George, S.; Mini, K. N.; Supriya, K.

    2015-03-01

    Reactive power flow in a long transmission line plays a vital role in power transfer capability and voltage stability in power system. Traditionally, shunt connected compensators are used to control reactive power in long transmission line. Thyristor controlled reactor is used to control reactive power under lightly loaded condition. By controlling firing angle of thyristor, it is possible to control reactive power in the transmission lines. However, thyristor controlled reactor will inject harmonic current into the system. An attempt to reduce reactive power injection will increase harmonic distortion in the line current and vice versa. Thus, there is a trade-off between reactive power injection and harmonics in current. By optimally controlling the reactive power injection, harmonics in current can be brought within the specified limit. In this paper, a Fuzzy Logic Controller is implemented to obtain optimal control of reactive power of the compensator to maintain voltage and harmonic in current within the limits. An algorithm which optimizes the firing angle in each fuzzy subset by calculating the rank of feasible firing angles is proposed for the construction of rules in Fuzzy Logic Controller. The novelty of the algorithm is that it uses a simple error formula for the calculation of the rank of the feasible firing angles in each fuzzy subset.

  18. Design of high power rectification power supply based on digital control

    For typical high power rectification power supply, a design based on digital control is introduced. The feasibility and superiority of the digital control scheme were verified through the design and experimental results of the filament power supply for high current ion source of NBI. The application of digital control scheme, making the filament power supply design is more intelligent and simple, as related applications provide a reference. (authors)

  19. Advanced Electric Distribution, Switching, and Conversion Technology for Power Control

    Soltis, James V.

    1998-01-01

    The Electrical Power Control Unit currently under development by Sundstrand Aerospace for use on the Fluids Combustion Facility of the International Space Station is the precursor of modular power distribution and conversion concepts for future spacecraft and aircraft applications. This unit combines modular current-limiting flexible remote power controllers and paralleled power converters into one package. Each unit includes three 1-kW, current-limiting power converter modules designed for a variable-ratio load sharing capability. The flexible remote power controllers can be used in parallel to match load requirements and can be programmed for an initial ON or OFF state on powerup. The unit contains an integral cold plate. The modularity and hybridization of the Electrical Power Control Unit sets the course for future spacecraft electrical power systems, both large and small. In such systems, the basic hybridized converter and flexible remote power controller building blocks could be configured to match power distribution and conversion capabilities to load requirements. In addition, the flexible remote power controllers could be configured in assemblies to feed multiple individual loads and could be used in parallel to meet the specific current requirements of each of those loads. Ultimately, the Electrical Power Control Unit design concept could evolve to a common switch module hybrid, or family of hybrids, for both converter and switchgear applications. By assembling hybrids of a common current rating and voltage class in parallel, researchers could readily adapt these units for multiple applications. The Electrical Power Control Unit concept has the potential to be scaled to larger and smaller ratings for both small and large spacecraft and for aircraft where high-power density, remote power controllers or power converters are required and a common replacement part is desired for multiples of a base current rating.

  20. A scheme to design power controller in wireless network systems

    In this Letter, power control problem is firstly studied at an angle of LQG measurement-feedback control problem. A stochastic uplink power control problem is considered for CDMA systems. An effective distributed algorithm is proposed based on stochastic linear quadratic optimal control theory assuming SIR measurements contain white noise. The presented scheme minimizes the sum of the power and the error of SIR. A measurement-feedback power controller is designed by constructing an optimization problem of a stochastic linear quadratic type in Krein space and solving the Kalman filter problem for the systems

  1. Sliding mode control of switching power converters techniques and implementation

    Tan, Siew-Chong; Tse, Chi-Kong

    2011-01-01

    Sliding Mode Control of Switching Power Converters: Techniques and Implementation is perhaps the first in-depth account of how sliding mode controllers can be practically engineered to optimize control of power converters. A complete understanding of this process is timely and necessary, as the electronics industry moves toward the use of renewable energy sources and widely varying loads that can be adequately supported only by power converters using nonlinear controllers.Of the various advanced control methods used to handle the complex requirements of power conversion systems, sliding mode c

  2. Power system stabilizers based on modern control techniques

    Malik, O.P.; Chen, G.P.; Zhang, Y.; El-Metwally, K. [Calgary Univ., AB (Canada). Dept. of Electrical and Computer Engineering

    1994-12-31

    Developments in digital technology have made it feasible to develop and implement improved controllers based on sophisticated control techniques. Power system stabilizers based on adaptive control, fuzzy logic and artificial networks are being developed. Each of these control techniques possesses unique features and strengths. In this paper, the relative performance of power systems stabilizers based on adaptive control, fuzzy logic and neural network, both in simulation studies and real time tests on a physical model of a power system, is presented and compared to that of a fixed parameter conventional power system stabilizer. (author) 16 refs., 45 figs., 3 tabs.

  3. Reviewing surveillance activities in nuclear power plants

    This document provides guidance to Operational Safety Review Teams (OSARTs) for reviewing surveillance activities at a nuclear power plant. In addition, the document contains reference material to support the review of surveillance activities, to assist within the Technical Support area and to ensure consistency between individual reviews. Drafts of the document have already been used on several OSART missions and found to be useful. The document first considers the objectives of an excellent surveillance programme. Investigations to determine the quality of the surveillance programme are then discussed. The attributes of an excellent surveillance programme are listed. Advice follows on how to phrase questions so as to obtain an informative response on surveillance features. Finally, specific equipment is mentioned that should be considered when reviewing functional tests. Four annexes provide examples drawn from operating nuclear power plants. They were selected to supplement the main text of the document with the best international practices as found in OSART reviews. They should in no way limit the acceptance and development of alternative approaches that lead to equivalent or better results. Refs, figs and tabs

  4. Modeling and control of sustainable power systems

    Wang, Lingfeng

    2011-01-01

    The concept of the smart grid promises the world an efficient and intelligent approach of managing energy production, transportation, and consumption by incorporating intelligence, efficiency, and optimality into the power grid. Both energy providers and consumers can take advantage of the convenience, reliability, and energy savings achieved by real-time and intelligent energy management. To this end, the current power grid is experiencing drastic changes and upgrades. For instance, more significant green energy resources such as wind power and solar power are being integrated into the power

  5. Coordinated Voltage Control of Active Distribution Network

    Xie Jiang

    2016-01-01

    Full Text Available This paper presents a centralized coordinated voltage control method for active distribution network to solve off-limit problem of voltage after incorporation of distributed generation (DG. The proposed method consists of two parts, it coordinated primal-dual interior point method-based voltage regulation schemes of DG reactive powers and capacitors with centralized on-load tap changer (OLTC controlling method which utilizes system’s maximum and minimum voltages, to improve the qualified rate of voltage and reduce the operation numbers of OLTC. The proposed coordination has considered the cost of capacitors. The method is tested using a radial edited IEEE-33 nodes distribution network which is modelled using MATLAB.

  6. A minimum attention control center for nuclear power plants

    Control Centers for Nuclear Power Plants have characteristically been designed for maximum attention by the operating staffs of these plants. Consequently, the monitoring, control and diagnostics oriented cognitive activities by these staffs, were mostly ''data-driven'' in nature. This paper addresses a control center concept, under development by Combustion Engineering, that promotes a more ''information-driven'' cognitive interaction process between the operator and the plant. The more ''intelligent'' and therefore less attentive nature of such interactive process utilizes computer implemented cognitive engineered algorithms. The underlying structure of these algorithms is based upon the Critical Function/Success Path monitoring principle. The paper highlights a typical implementation of the minimum attention concept for the handling of unfamiliar safety related events. (author)

  7. Development of hydraulic brake actuator for active brake control; Active brake seigyoyo yuatsu booster no kaihatsu

    Konishi, Y.; Hattori, M. Sugisawa, M.; Nishii, M. [Aisin Seiki Co. Ltd., Aichi (Japan)

    1997-10-01

    Recently, application of active brake control systems of the vehicle are increasing. (Vehicle stability control, Panic brake assist ) We have developed a new hydraulic brake actuator for active brake control systems. New hydraulic brake actuator is composed of the three parts. (Hydraulic booster unit, Power supply unit, Control valve unit) This report describes the construction of the new hydraulic booster unit. 2 refs., 10 figs.

  8. Fiber MOPAs with high control and high power

    Nilsson, J.; Yoo, S.; Dupriez, P.; Farrell, C.; Abidin, M.S.Z.; Ji, J; Maran, J.-N.; Codemard, C. A.; Jeong, Y.; Sahu, J.K.; Richardson, D J; Payne, D. N.

    2008-01-01

    High power fiber sources have reached several kilowatts of output power, and are now leading contenders for many applications. Important attractions include control, efficiency, manufacturability, and reliability. We will exemplify opportunities and limitations for these revolutionary sources.

  9. Voltage harmonics mitigation through hybrid active power filer

    Fast dynamic response, high efficiency, low cost and small size of power electronic converters have exponentially increased their use in modern power system which resulted in harmonically distorted voltage and currents. Voltage harmonics mainly caused by current harmonics are more dangerous as performance and expected operating life of other power system equipment are affected by harmonically distorted supply voltage. Electronic filter circuits are used to improve system power quality by mitigating adverse effects of harmonics. Hybrid filters having advantages of both passive and active filters are preferred to resolve the problem of harmonics efficiently and avoiding any chance of resonance. In this paper, a three phase three wire network is considered to supply an adjustable speed drive represented by a resistive load connected across a three phase bridge rectifier. Simulation of the considered system shows THD (Total Harmonic Distortion) of 18.91 and 7.61 percentage in supply current and voltage respectively. A HAPF (Hybrid Active Power Filter) is proposed to reduce these THD values below 5 percentage as recommended by IEEE Standard-519. P-Q theorem is used to calculate required parameters for proposed filter, which is implemented through hysteresis control. Simulation results confirm the effectiveness of the designed filter as THD for both current and voltage have reduced below allowable limit of 5 percentage. (author)

  10. Voltage Harmonics Mitigation through Hybrid Active Power Filter

    Anwer Ali Sahito

    2016-01-01

    Full Text Available Fast dynamic response, high efficiency, low cost and small size of power electronic converters have exponentially increased their use in modern power system which resulted in harmonically distorted voltage and currents. Voltage harmonics mainly caused by current harmonics are more dangerous as performance and expected operating life of other power system equipment are affected by harmonically distorted supply voltage. Electronic filter circuits are used to improve system power quality by mitigating adverse effects of harmonics. Hybrid filters having advantages of both passive and active filters are preferred to resolve the problem of harmonics efficiently and avoiding any chance of resonance. In this paper, a three phase three wire network is considered to supply an adjustable speed drive represented by a resistive load connected across a three phase bridge rectifier. Simulation of the considered system shows THD (Total Harmonic Distortion of 18.91 and 7.61% in supply current and voltage respectively. A HAPF (Hybrid Active Power Filter is proposed to reduce these THD values below 5% as recommended by IEEE Standard-519. P-Q theorem is used to calculate required parameters for proposed filter, which is implemented through hysteresis control. Simulation results confirm the effectiveness of the designed filter as THD for both current and voltage have reduced below allowable limit of 5%.

  11. Innovative Digitally Controlled Particle Accelerator Magnet Power Supply

    Nielsen, Rasmus Ørndrup; Bidoggia, Benoit; Maheshwari, Ram Krishan; Török, Lajos

    Particle accelerator magnet power supplies needs to be extremely precise. A new and innovative power supply for particle accelerator magnets is proposed. The topologies for the input and the output converter are shown and the control architecture is described.......Particle accelerator magnet power supplies needs to be extremely precise. A new and innovative power supply for particle accelerator magnets is proposed. The topologies for the input and the output converter are shown and the control architecture is described....

  12. Power electronic converters PWM strategies and current control techniques

    Monmasson, Eric

    2013-01-01

    A voltage converter changes the voltage of an electrical power source and is usually combined with other components to create a power supply. This title is devoted to the control of static converters, which deals with pulse-width modulation (PWM) techniques, and also discusses methods for current control. Various application cases are treated. The book is ideal for professionals in power engineering, power electronics, and electric drives industries, as well as practicing engineers, university professors, postdoctoral fellows, and graduate students.

  13. Multiagent based protection and control in decentralized electric power systems

    Saleem, Arshad; Lind, Morten; Veloso, Manuela

    2010-01-01

    Electric power systems are going through a major change both in their physical and control structure. A large num- ber of small and geographically dispersed power generation units (e.g., wind turbines, solar cells, plug-in electric cars) are replacing big centralized power plants. This shift has ...... explicit modeling of capabilities, states, roles and role transition in agents can capture the control and automation in electric power systems. We present illustrative results from using our proposed schema in realistic simulations....

  14. High Performance Low Cost Digitally Controlled Power Conversion Technology

    Jakobsen, Lars Tønnes; Andersen, Michael Andreas E.; Thomsen, Ole Cornelius; Niemann, Hans Henrik; Tøttrup, Peter

    2008-01-01

    Digital control of switch-mode power supplies and converters has within the last decade evolved from being an academic subject to an emerging market in the power electronics industry. This development has been pushed mainly by the computer industry that is looking towards digital power management in order to reduce the power consumption of servers and datacenters. The work presented in this thesis includes digital control methods for switch-mode converters implemented in microcontrollers, dig...

  15. Performance of Uplink Fractional Power Control in UTRAN LTE

    Úbeda Castellanos, Carlos; López Villa, Dimas; Rosa, Claudio; Pedersen, Klaus I.; Calabrese, Francesco Davide; Michaelsen, Per-Henrik; Michel, Jürgen

    inter-cell interference. As a result, the role of the power control becomes decisive to provide the required SINR, while controlling at the same time the interference caused to neighboring cells. This is the target of the Fractional Power Control (FPC) algorithm lately approved in 3GPP. This paper...

  16. A Low-Power Microcontroller with Accuracy-Controlled Event-Driven Signal Processing Unit for Rare-Event Activity-Sensing IoT Devices

    Daejin Park

    2015-01-01

    Full Text Available A specially designed microcontroller with event-driven sensor data processing unit (EPU is proposed to provide energy-efficient sensor data acquisition for Internet of Things (IoT devices in rare-event human activity sensing applications. Rare-event sensing applications using a remotely installed IoT sensor device have a property of very long event-to-event distance, so that the inaccurate sensor data processing in a certain range of accuracy error is enough to extract appropriate events from the collected sensing data. The proposed signal-to-event converter (S2E as a preprocessor of the conventional sensor interface extracts a set of atomic events with the specific features of interest and performs an early evaluation for the featured points of the incoming sensor signal. The conventional sensor data processing such as DSPs or software-driven algorithm to classify the meaningful event from the collected sensor data could be accomplished by the proposed event processing unit (EPU. The proposed microcontroller architecture enables an energy efficient signal processing for rare-event sensing applications. The implemented system-on-chip (SoC including the proposed building blocks is fabricated with additional 7500 NAND gates and 1-KB SRAM tracer in 0.18 um CMOS process, consuming only 20% compared to the conventional sensor data processing method for human hand-gesture detection.

  17. Active Vibration Control of Tethered Solar Power Satellite during Attitude Maneuvering%绳系太阳能发电卫星姿态机动的主动振动控制

    周荻; 范继祥

    2012-01-01

    针对绳系太阳能发电卫星大角度回转机动时太阳能板的振动抑制问题,提出了主姿态控制和基于绳中张力的主动振动控制技术相结合的复合控制方法.建立了绳系太阳能发电卫星系统的动力学方程,并基于任务函数控制算法设计了主控制器保证卫星姿态的渐近稳定和挠性结构振动的衰减性;考虑到绳的非线性特性,基于任务函数控制算法设计了绳系卫星系统的主动振动抑制辅助控制器来抑制挠性结构的振动.设计的同时证明了系统的稳定性.将该方法应用于绳系卫星的大角度单轴回转机动的仿真研究,结果表明:该方法不仅能够使绳系卫星完成姿态机动,而且能够有效地抑制太阳能板的振动.%For vibration suppression of tethered Solar Power Satellite (SPS) during large-angle slewing maneuver, a composite control method is proposed by combining main attitude control with active vibration control based on tether tension. Dynamics equations for the slewing motion of tethered SPS are presented. A mission Function (MF) Control Algorithm is applied to design these two controllers. The main controller is able not only to implement attitude maneuvering of tethered satellite but also suppress the relatively large amplitude vibration of the flexible solar panel. The compensate control system acting on the comers of flexible solar panels is required for the further vibration suppression, and the nonlinearity of the flexible tether is taken into account in the controller design. In the design process, the stability of the vibration control system is proved. Simulation results demonstrate that the proposed approach can significantly suppress the vibration of the flexible solar panel during and after the maneuver operation.

  18. Upgrading the Reactor Power Control Concept with a Modern Digital Control System

    Within the framework of a retrofit project, a reactor power instrumentation and control system (REALL) - consisting of a limiting system and the respective reactor control systems - was retrofitted and modernized in a 1450-MW-nuclear-power-plant in Baden-Wuerttemberg. The REALL process control functions were implemented within a modern and completely digitized control system that has been designed for use in safety I and C applications. Along with the installation of the digital control system, the associated hardware was adapted to today's state of the art. At the same time, the given potential for improvement, as revealed during the plant's operation so far, was taken into account in the programming. In order to provide for transparent and quality-assured project management, the implementation was based on a stage plan consisting of several steps, along with specific milestones. Final commissioning of the modern digital control system took place during the 2008 plant overhaul. Despite the complex commissioning procedure, it was possible to avoid a major prolongation of the plant's downtime and to keep within a rough 4-week timeframe that had originally been defined for the plant overhaul to adequate structuring of the project, goal-oriented implementation of preparatory infrastructural measures and adequate scheduling of the coordinated activities of the installation and commissioning teams entrusted with the commissioning of the digital control system during the overhaul activities. (author)

  19. Simple power supply for power load controlled isoelectric focusing

    Duša, Filip; Šlais, Karel

    2014-01-01

    Roč. 35, č. 8 (2014), s. 1114-1117. ISSN 0173-0835 R&D Projects: GA MV VG20102015023 Institutional support: RVO:68081715 Keywords : isoelectric focusing * power supply * voltage multiplier Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 3.028, year: 2014 http://hdl.handle.net/11104/0231022

  20. Resistojet control and power for high frequency ac buses

    Gruber, Robert P.

    1987-01-01

    Resistojets are operational on many geosynchronous communication satellites which all use dc power buses. Multipropellant resistojets were selected for the Initial Operating Capability (IOC) Space Station which will supply 208 V, 20 kHz power. This paper discusses resistojet heater temperature controllers and passive power regulation methods for ac power systems. A simple passive power regulation method suitable for use with regulated sinusoidal or square wave power was designed and tested using the Space Station multipropellant resistojet. The breadboard delivered 20 kHz power to the resistojet heater. Cold start surge current limiting, a power efficiency of 95 percent, and power regulation of better than 2 percent were demonstrated with a two component, 500 W breadboard power controller having a mass of 0.6 kg.

  1. Design Of Start-up Power Circuit For Control Power Supplies With Wide Input Voltage Variation

    Saichand, K; Kumrawat, Akshay; JOHN, VINOD

    2013-01-01

    This paper presents the design of a start up power circuit for a control power supply (CPS) which feeds power to the sub-systems of High Power Converters (HPC). The sub-systems such as gate drive card, annunciation card, protection and delay card etc; needs to be provided power for the operation of a HPC. The control power supply (CPS) is designed to operate over a wide range of input voltage from 90Vac to 270Vac. The CPS output supplies power at a desired voltage of Vout =24V to the auxil...

  2. Cross-Layer Cooperative Power Control in Heterogeneous Multihop Networks

    Feng Tian

    2016-01-01

    Full Text Available This paper investigates how to perform optimal cooperative power control for the coexistence of heterogeneous multihop networks. Although power control on the node level in multihop networks is a difficult problem due to its large design space and the coupling relationship of power control with scheduling and routing, we formulate a multiobjective optimization problem for the total power consumption of the two heterogeneous multihop networks with discretized power level. We reformulate the nonlinear constraint (relationship between power and capacity into the linear one by piecewise linearization procedure and offer an in-depth study of cooperative power control in terms of its optimal power—the minimum power consumption with discretized power level for both heterogeneous multihop networks. Through a novel approach based on adaptive weighted-sum method, we transform the multiobjective optimization problem into a single-objective optimization problem and find the set of Pareto-optimal points iteratively. Using the Pareto-optimal points, we construct the minimum power curve. Using numerical results, we demonstrate that it can save more energy with cooperative power control than the case without cooperative power control.

  3. Application of fuzzy logic controller in a nuclear power plant

    Possible application of a fuzzy logic controller in a PWR nuclear power plant is investigated in this paper. A simplified model of the complex dynamics of the system is used for simulation purposes. The goal is to keep average coolant temperature as close as possible to a desired (but changing) reference value. The position of the control rods is selected as control variable. Simulation results demonstrate the possibility of using fuzzy logic controllers in load following control of nuclear power plants

  4. Power control by superconducting magnetic energy storage for load change compensation and power system stabilization in interconnected power system

    Tada, M; Mitani, Yasunori; K. Tsuji

    1995-01-01

    This paper describes a load change compensation by a superconducting magnetic energy storage (SMES) which is assumed to be installed in a power system for power system stabilization. A simultaneous control strategy of SMES for load change compensation as well as for power system stabilization in a longitudinally interconnected power system is derived. Several numerical examples demonstrate the significant effectiveness of the SMES

  5. Power system small signal stability analysis and control

    Mondal, Debasish; Sengupta, Aparajita

    2014-01-01

    Power System Small Signal Stability Analysis and Control presents a detailed analysis of the problem of severe outages due to the sustained growth of small signal oscillations in modern interconnected power systems. The ever-expanding nature of power systems and the rapid upgrade to smart grid technologies call for the implementation of robust and optimal controls. Power systems that are forced to operate close to their stability limit have resulted in the use of control devices by utility companies to improve the performance of the transmission system against commonly occurring power system

  6. Integrated power electronic converters and digital control

    Emadi, Ali; Nie, Zhong

    2009-01-01

    Non-isolated DC-DC ConvertersBuck ConverterBoost ConverterBuck-Boost ConverterIsolated DC-DC ConvertersFlyback ConverterForward ConverterPush-Pull ConverterFull-Bridge ConverterHalf-Bridge ConverterPower Factor CorrectionConcept of PFCGeneral Classification of PFC CircuitsHigh Switching Frequency Topologies for PFCApplication of PFC in Advanced Motor DrivesIntegrated Switched-Mode Power ConvertersSwitched-Mode Power SuppliesThe Concept of Integrated ConverterDefinition of Integrated Switched-Mode Power Supplies (ISMPS)Boost-Type Integrated TopologiesGeneral Structure of Boost-Type Integrated T

  7. Emissions control for ground power gas turbines

    Rudney, R. A.; Priem, R. J.; Juhasz, A. J.; Anderson, D. N.; Mroz, T. S.; Mularz, E. J.

    1977-01-01

    The similarities and differences of emissions reduction technology for aircraft and ground power gas turbines is described. The capability of this technology to reduce ground power emissions to meet existing and proposed emissions standards is presented and discussed. Those areas where the developing aircraft gas turbine technology may have direct application to ground power and those areas where the needed technology may be unique to the ground power mission are pointed out. Emissions reduction technology varying from simple combustor modifications to the use of advanced combustor concepts, such as catalysis, is described and discussed.

  8. Influence in electricity market on power system control

    The purpose of this paper is to extend the consideration of the Croatian Power System Control Model beginning with the environment of the domestic and following with the European electricity market. The paper actually presents a continuation of a series of similar papers on the power system control model, but now within the environment of the electricity market and its influence on the power system control structure and functions. (author)

  9. Reactive power compensation using a fuzzy logic controlled synchronous motor

    This paper introduces the use of a fuzzy logic controlled synchronous motor for reactive power compensation. The fuzzy logic controlled synchronous motor can give a very fast response to the reactive power required by the load. Therefore, the over or under compensation and time delay are eliminated in this system. It is concluded that the reactive power compensation system with a fuzzy logic controlled synchronous motor is reliable, sensitive, economical, faster and more efficient than an other one with capacitor groups

  10. Strategies for reactive power control in wind farms with STATCOM

    Díaz González, Francisco; Martínez Rojas, Marcela; Sumper, Andreas; Gomis Bellmunt, Oriol

    2010-01-01

    This paper presents three strategies for reactive power control in wind farms with STATCOM. First, the STATCOM system and its applications in electric power systems and wind farms are shown. Second, the modeling done of the wind farm, the STATCOM and the network are presented. Finally, control strategies for reactive power delivered by the park to the network when required are shown. The result of the implementation of each control strategy is shown by simulation.

  11. Changes in control room at Swedish nuclear power plants

    The Swedish nuclear power plants were commissioned during a period between 1972 and 1985 and the instrumentation and control equipment are basically from that period. For several years there have been plans made for changes in all the nuclear power plants and to a certain extent the changes in control equipment and monitoring rooms have also been implemented. The object of this project was to make a comprehensive review of the changes in control room design implemented in the Swedish nuclear power plants and to describe how the MTO- (Man-Technology-Organisation) and (Man-Machine-Interface) -issues have been integrated in the process. The survey is intended to give an overall picture of the changes in control room design and man-machine-interface made in the Swedish control rooms, in order to get a deeper knowledge of the change management process and its results as well as of the management of MTO-issues in these projects. The units included in this survey are: Oskarhamn reactor 2 and 3; Ringhals reactor 2, 3 and 4; Forsmark reactor 1, 2 and 3. The Oskarshamn 1 unit has not been included in this report as it has recently undergone an extensive modernisation program as well as a detailed inspection by the SKI (Swedish Nuclear Power Inspectorate). At Ringhals 2 the modernisation work is carried out at present and the unit is also subjected to extensive inspection activities carried out by SKI and is therefore not part of this survey. This report also includes a short description of relevant standards and requirements. Then follows a presentation of the results of the plant survey, presented as case studies for three companies OKG, Ringhals and FKA. Control room changes are summarized as well as the results on specific MTO issues which has been surveyed. In all the power companies there is a joint way of working with projects concerning plant modifications. This process is described for each company separately. In the concluding of the report the strengths and

  12. Implementation of a Novel Control Strategy Using Fuzzy Logic Controller to Shunt Active Filter for Line Harmonic Reduction

    T Manigandan; N. Senthilnathan

    2012-01-01

    Problem statement: Now days, power quality has been given attention due to the intensive use of power electronic equipments in all types of industries such as steel, paper, textile industries and so on. These power electronic devices induce harmonic distortion into the supply lines which gives rise to many undesirable effects. Approach: This study presents a new method for harmonic and reactive power compensation with a Fuzzy logic controller and a new control algorithm for active power filte...

  13. Report on the status of instrumentation and control in Swedish nuclear power plants

    During 1988 the twelve nuclear power units in Sweden generated 69 TWh, which was 45% of the total electric power produced in Sweden. The production capacity of the nuclear power plants increased successively by upgrading the units to higher nominal power levels. The paper presents an overview of activities on control and instrumentation in the following: maintenance, renewal of the I and C systems, training. The operational data of Swedish reactor units are presented. (author). 1 tab

  14. Active Spacecraft Potential Control Investigation

    Torkar, K.; Nakamura, R.; Tajmar, M.; Scharlemann, C.; Jeszenszky, H.; Laky, G.; Fremuth, G.; Escoubet, C. P.; Svenes, K.

    2016-03-01

    In tenuous plasma the floating potential of sunlit spacecraft reaches tens of volts, positive. The corresponding field disturbs measurements of the ambient plasma by electron and ion sensors and can reduce micro-channel plate lifetime in electron detectors owing to large fluxes of attracted photoelectrons. Also the accuracy of electric field measurements may suffer from a high spacecraft potential. The Active Spacecraft Potential Control (ASPOC) neutralizes the spacecraft potential by releasing positive charge produced by indium ion emitters. The method has been successfully applied on other spacecraft such as Cluster and Double Star. Two ASPOC units are present on each spacecraft. Each unit contains four ion emitters, whereby one emitter per instrument is operated at a time. ASPOC for the Magnetospheric Multiscale (MMS) mission includes new developments in the design of the emitters and the electronics. New features include the use of capillaries instead of needles, new materials for the emitters and their internal thermal insulators, an extended voltage and current range of the electronics, both for ion emission and heating purposes, and a more capable control software. This enables lower spacecraft potentials, higher reliability, and a more uniform potential structure in the spacecraft's sheath compared to previous missions. Results from on-ground testing demonstrate compliance with requirements. Model calculations confirm the findings from previous applications that the plasma measurements will not be affected by the beam's space charge. Finally, the various operating modes to adapt to changing boundary conditions are described along with the main data products.

  15. PMBLDC motor drive with power factor correction controller

    George, G.J.; Ramachandran, Rakesh; Arun, N.

    2012-01-01

    This paper presents a boost converter configuration, control scheme and design of single phase power factor controller for permanent magnet brushless DC motor (PMBLDCM) drive. PMBLDC motors are the latest choice of researchers, due to the high efficiency, silent operation, compact size, high...... reliability, and low maintenance requirements. The proposed Power Factor Controller topology improves power quality by improving performance of PMBLDCM drive, such as reduction of AC main current harmonics, near unity power factor. PFC converter forces the drive to draw sinusoidal supply current in phase with...... supply voltage. It uses a boost converter to obtain unity power factor with improved performance. The system includes a speed controller for PMBLDC drive and a voltage controller for boost converter.. The voltage or speed controllers can be realized using proportional integral (PI) controller...

  16. Compensation of Disturbed Load Currents Using Active Power Filter and Generalized Non-active Power Theory

    Lettl, J.; Šimek, Petr; Valouch, Viktor

    Prague: Electromagnetics Academy, 2015, s. 2500-2505. ISSN 1559-9450. [Progress In Electromagnetics Research Symposium Proceedings. Prague (CZ), 06.07.2015-09.07.2015] Institutional support: RVO:61388998 Keywords : disturbed load * GNP (Generalized Non-active Power) * parallel compensation Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering www.piers.org

  17. A Vector Control for Grid-connected Wind Power Generation with Doubly Fed Induction Generator

    Kai, Takaaki; Tanaka, Yuji; Kaneda, Hirotoshi; Kobayashi, Daichi; Tanaka, Akio

    Recently, doubly fed induction generator (DFIG) and synchronous generator are mostly applied for wind power generation due to high efficiently for wind energy capture. An inverter system is required to control wind turbine speed and power factor in those generators. The inverter rating of the synchronous generator equals to generator rating. However, DFIG has the advantage that the inverter rating is about 25% to the generator rating. The paper describes a vector control of DFIG inter-connected to power line. The performance of proposed vector control is examined using power system simulation software PSCAD/EMTDC for the DFIG inter-connected to 6.6kv distribution line. The results show good dynamic responses and high accuracy to the stator active power control and the stator reactive power control.

  18. Wind Powering America FY07 Activities Summary

    2008-02-01

    The Wind Powering America FY07 Activities Summary reflects the accomplishments of our state wind working groups, our programs at the National Renewable Energy Laboratory, and our partner organizations. The national WPA team remains a leading force for moving wind energy forward in the United States. WPA continues to work with its national, regional, and state partners to communicate the opportunities and benefits of wind energy to a diverse set of stakeholders. WPA now has 30 state wind working groups (welcoming Georgia and Wisconsin in 2007) that form strategic alliances to communicate wind's benefits to the state stakeholders. More than 140 members of national and state public and private sector organizations from 39 U.S. states and Canada attended the 6th Annual WPA All-States Summit in Los Angeles in June. WPA's emphasis remains on the rural agricultural sector, which stands to reap the significant economic development benefits of wind energy development. Additionally, WPA continues its program of outreach, education, and technical assistance to Native American communities, public power entities, and regulatory and legislative bodies.

  19. Occupational dose control in Nuclear Power Plants

    Reduction in occupational exposure at nuclear power plants is desirable not only in the interest of the health and safety of plant personnel, but also because it enhances the safety and reliability of the plants. This report summarises the current trends of doses to workers at nuclear power plants and the achievements and developments regarding methods for their reduction

  20. Wind Farm Coordinated Control for Power Optimization

    SHU Jin; HAO Zhiguo; ZHANG Baohui; BO Zhiqian

    2011-01-01

    The total wind energy capture would decrease with the aerodynamic interaction among turbines known as wake effect, and the conventional maximum power point track (MPPT) schemes for individual wind turbine generator (WTG) can not maximize the total farm power.

  1. Synchronously Driven Power Converter Controller Solution for MedAustron

    Šepetavc, Luka; Tavčar, Rok; Moser, Roland; Gutleber, Johannes

    2011-01-01

    MedAustron is an ion beam cancer therapy and research centre currently under construction in Wiener Neustadt, Austria. This facility features a synchrotron particle accelerator for light ions. Cosylab is closely working together with MedAustron on the development of a power converter controller (PCC) for the 260 deployed power converters – power supplies. Power converters deliver power to magnets used for focusing and steering particle beams. We have designed and developed software and hardware which allows integration of different types of power converters into MedAustron's control system (MACS). PCC's role is to synchronously control and monitor connected power converters. Custom real-time fibre optics link and modular front end devices have been designed for this purpose. Modular front end devices make it possible to interface with almost any type of power converter – with or without built in regulation logic. We implemented realtime mechanisms and a dedicated real-time fibre link to ...

  2. Palm Power Free-Piston Stirling Engine Control Electronics

    Keiter, Douglas E.; Holliday, Ezekiel

    2007-01-01

    A prototype 35We, JP-8 fueled, soldier-wearable power system for the DARPA Palm Power program has been developed and tested by Sunpower. A hermetically-sealed 42We Sunpower Free-Piston Stirling Engine (FPSE) with integral linear alternator is the prime mover for this system. To maximize system efficiency over a broad range of output power, a non-dissipative, highly efficient electronic control system which modulates engine output power by varying piston stroke and converts the AC output voltage of the FPSE into 28Vdc for the Palm Power end user, has been designed and demonstrated as an integral component of the Palm Power system. This paper reviews the current status and progress made in developing the control electronics for the Palm Power system, in addition to describing the operation and demonstrated performance of the engine controller in the context of the current JP-8 fueled Palm Power system.

  3. Power control for wind turbines in weak grids: Concepts development

    Bindner, H.

    1999-01-01

    and analyze methods and technologies for making it viable to utilize more of the wind potential in remote areas. The suggestion is to develop a power control concept for wind turbines which will even out thepower fluctuations and make it possible to increase the wind energy penetration. The main....... The mainissues in the assessment of the power control concept are the storage capacity and power rating compared to the installed wind power capacity. The model SimStore has been developed to assess that. The economic investigations have shown that for smallsystems where only small amounts of wind...... concept will make wind power more firm and possible to connect to weaker grids. So, when the concept is matured, theexpectation is that for certain wind power installations, the cost of the power control is paid back as added wind power capacity value and saved grid reinforcement costs. Different systems...

  4. Wind Powering America FY06 Activities Summary

    2007-02-01

    The Wind Powering America FY06 Activities Summary reflects the accomplishments of our state wind working groups, our programs at the National Renewable Energy Laboratory, and our partner organizations. The national WPA team remains a leading force for moving wind energy forward in the United States. WPA continues to work with its national, regional, and state partners to communicate the opportunities and benefits of wind energy to a diverse set of stakeholders. WPA now has 29 state wind working groups (welcoming New Jersey, Indiana, Illinois, and Missouri in 2006) that form strategic alliances to communicate wind's benefits to the state stakeholders. More than 120 members of national and state public and private sector organizations from 34 states attended the 5th Annual WPA All-States Summit in Pittsburgh in June.

  5. Modern Control Aspects In Doubly Fed Induction Generator Based Power Systems: A Review

    J.S.LATHER, S.S.DHILLON, S.MARWAHA

    2013-06-01

    Full Text Available Doubly fed induction generators (DFIG based wind turbine is an emerging technology, which becomes increasingly popular due to its various advantages over fixed speed generator systems. A DFIG based wind turbine has an ability to generate maximum power with varying and adjustable speed, ability to control active and reactive power by the integration of electronic power converters, low power rating of cost converter components, and so on. This study presents an overview and literature survey over past few decades on the different problems associated due to penetration of WT-DFIG in the power system and control aspects of DFIG.

  6. Investigation of axial power gradients near a control rod tip

    Highlights: → Pin power gradients near BWR control rod tips have been investigated. → A control rod tip is modeled in MCNP and compared to simplified 2D/3D geometry. → Small nodes increases pin power gradients; standard nodes underestimates gradients. → The MCNP results are validated against axial gamma scan of a controlled fuel pin. - Abstract: Control rod withdrawal in BWRs induces large power steps in the adjacent fuel assemblies. This paper investigates how well a 2D/3D method, e.g., CASMO5/SIMULATE5 computes axial pin power gradients adjacent to an asymmetrical control-rod tip in a BWR. The ability to predict pin power gradients accurately is important for safety considerations whereas large powers steps induced by control rod withdrawal can cause Pellet Cladding Interaction. The computation of axial pin power gradients axially around a control rod tip is a challenging task for any nodal code. On top of that, asymmetrical control rod handles are present in some BWR designs. The lattice code CASMO requires diagonal symmetry of all control rod parts. This introduces an error in computed pin power gradients that has been evaluated by Monte Carlo calculations. The results show that CASMO5/SIMULATE5, despite the asymmetrical control rod handle, is able to predict the axial pin power gradient within 1%/cm for axial nodal sizes of 15-3.68 cm. However, a nodal size of 3.68 cm still causes underestimations of pin power gradients compared with 1 cm nodes. Furthermore, if conventional node sizes are used, ∼15 cm, pin power gradients can be underestimated by over 50% compared with 1 cm nodes. The detailed axial pin power profiles from MCNP are corroborated by measured gamma scan data on fuel rods irradiated adjacent to control rods.

  7. A Review of Parallel Operation of Active Power Filters in the Distributed Generation System

    Khadem, Shafiuzzaman Khan; Basu, Malabika; Conlon, Michael

    2011-01-01

    In this paper a technical review of parallel operation of Active Power Filter (APF) for harmonic power compensation in distributed generation (DG) network has been presented. Controlling methods and connection topologies with their pros and cons are described. Recent improvements in controlling and future trends for the application of APFs in distributed mode are also identified.

  8. Decomposing Objectives and Functions in Power System Operation and Control

    Heussen, Kai; Lind, Morten

    2009-01-01

    The introduction of many new energy solutions requires the adaptation of classical operation paradigms in power systems. In the standard paradigm, a power system is some equivalent of a synchronous generators, a power line and an uncontrollable load. This paradigm has been challenged by a diverse...... mix of challenges posed by renewable energy sources, demand response technologies and smartgrid concepts, affecting all areas of power system operation. Both, new control modes and changes in market design are required. This paper presents a mean-ends perspective to the analysis of the control...... structures and operation paradigms in present power systems. In a top-down approach, traditional frequency- and area-control mechanisms are formalized. It is demonstrated that future power system operation paradigms with different generation control modes and controllable demand can be modeled in a coherent...

  9. Optimized control strategy for crowbarless solid state modular power supply

    Solid state modular power supply with series connected IGBT based power modules have been employed as high voltage bias power supply of klystron amplifier. Auxiliary compensation of full wave inverter bridge with ZVS/ZCS operations of all IGBTs over entire operating range is incorporated. An optimized control strategy has been adopted for this power supply needing no output filter, making this scheme crowbarless and is presented in this paper. DSP based fully digital control with same duty cycle for all power modules, have been incorporated for regulating this power supply along with adequate protection features. Input to this power supply is taken directly from 11 kV line and the input system is intentionally made 24 pulsed to reduce the input harmonics, improve the input power factor significantly, there by requiring no line filters. Various steps have been taken to increase the efficiency of major subsystems, so as to improve the overall efficiency of this power supply significantly. (author)

  10. Magnetic Levitation Technique for Active Vibration Control

    Hoque, Emdadul; Mizuno, Takeshi

    2010-01-01

    A zero-power controlled magnetic levitation system has been presented in this chapter. The unique characteristic of the zero-power control system is that it can generate negative stiffness with zero control current in the steady-state which is realized in this chapter. The detail characteristics of the levitation system are investigated. Moreover, two major contributions, the stiffness adjustment and nonlinear compensation of the suspension system have been introduced elaborately. Often, ther...

  11. Design of a wind turbine pitch angle controller for power system stabilisation

    Jauch, Clemens; Islam, S.M.; Sørensen, Poul Ejnar;

    2007-01-01

    The design of a PID pitch angle controller for a fixed speed active-stall wind turbine, using the root locus method is described in this paper. The purpose of this controller is to enable an active-stall wind turbine to perform power system stabilisation. For the purpose of controller design, the...... transfer function of the wind turbine is derived from the wind turbine's step response. The performance of this controller is tested by simulation, where the wind turbine model with its pitch angle controller is connected to a power system model. The power system model employed here is a realistic model of...... controller can effectively contribute to power system stabilisation. (c) 2007 Elsevier Ltd. All rights reserved....

  12. Active power line conditioners design, simulation and implementation for improving power quality

    Revuelta, Patricio Salmeron; Litrán, Salvador Pérez

    2015-01-01

    Active Power Line Conditioners: Design, Simulation and Implementation for Improving Power Quality presents a rigorous theoretical and practical approach to active power line conditioners, one of the subjects of most interest in the field of power quality. Its broad approach offers a journey that will allow power engineering professionals, researchers, and graduate students to learn more about the latest landmarks on the different APLC configurations for load active compensation. By introducing the issues and equipment needs that arise when correcting the lack of power quality in power grids

  13. Optimization of constant power control of wind turbines to provide power reserves

    Vyver, Jan Van de; De Kooning, Jeroen; Meersman, Bart; Vandoorn, Tine; Vandevelde, Lieven

    2013-01-01

    In several countries, the wind power penetration increased tremendously in the last years. As the current wind turbines do not participate in frequency control nor reserve provision, this may compromise the proper functioning of the primary control and the provision of power reserves. If no actions are taken, increasing levels of wind penetration may result in serious problems concerning the stable operation of the power system. This paper focuses on the provision of power reserves by wind tu...

  14. Software-Based Wireless Power Transfer Platform for Various Power Control Experiments

    Sun-Han Hwang; Chung G. Kang; Yong-Ho Son; Byung-Jun Jang

    2015-01-01

    In this paper, we present the design and evaluation of a software-based wireless power transfer platform that enables the development of a prototype involving various open- and closed-loop power control functions. Our platform is based on a loosely coupled planar wireless power transfer circuit that uses a class-E power amplifier. In conjunction with this circuit, we implement flexible control functions using a National Instruments Data Acquisition (NI DAQ) board and algorithms in the MATLAB/...

  15. Robust FOPI controller design for power control of PHWR under step-back condition

    Highlights: • Robust stabilization of a highly nonlinear PHWR process. • A robust FOPI controller for a typical fractional-order NIOPTD-II plant. • Flat phase constraint is proposed to obtain a controller giving wide flat phase at gain crossover frequency. • FOPI controller designed for an operating condition of the PHWR produces a constant Phase margin for wide range of frequencies. • The proposed FOPI controller gives better performance compared to existing in the literature. - Abstract: This paper presents a stabilizing fractional-order proportional integral (FOPI) controller design for the power control of a highly nonlinear Pressurized Heavy Water Reactor (PHWR) under step-back condition. A single robust FOPI controller is designed utilizing stability boundary locus method for eight nuclear reactor models of the PHWR linearized at different operating points. A set of stabilizing controller parameters is obtained for a typical fractional-order two non-integer order plus time delay (NIOPTD-II) model of the reactor satisfying design specifications of phase margin and gain crossover frequency. Then a flat phase constraint is developed to find a controller giving wide flat phase at the desired gain crossover frequency. The controller obtained is found to give iso-damped closed-loop response for all linearized models of PHWR. Simulation results show that the proposed FOPI controller applied for active step-back in the reactor give a deadbeat tracking performance without any undershoot for all operating points, defined for variation in initial power level or control rod drop. The efficacy of the proposed FOPI controller is verified by comparing its performance with existing methods in the literature

  16. FACTS BASED CONTROLLER FOR INTERCONNECTED HYDROTHERMAL POWER SYSTEM

    Ravi Shankar

    2012-04-01

    Full Text Available This research paper introduce the FACTS based decentralized controller for load frequency control of two area interconnected hydrothermal power system considering the combined effect of RFB ( Redox Flow Batteries and TCPS ( Thyristor Control Phase Shifter as a FACTS device which is incorporated with tie-line power flowof the given system. The proposed controller is design using genetic algorithm based integral controller in which Integral Square Error (ISE criterion is consider for the optimization of the system error. This proposed controller is implemented into the two area interconnected hydrothermal power system and its different performance is studies with and without RFB and TCPS control scheme. This studies revels that the proposed controller gives better transient responses and helps in better stabilizing frequency response as well as improve the tie line power flow of the system.

  17. Design of the HL-2M power supply control system

    Highlights: • The control system is structured by using four kinds of control networks. • The controlling of converter is based on the real time network and FPGA. • With use of PROFINET, the status of all components can be monitored easily. • The SoE distinguishes input signals clearly to detect the fault rapidly. -- Abstract: The power supply control system is one of the most important local control systems of HL-2M tokamak. The power supply system of HL-2M is composed of four flywheel generator sets with total capacity of 600 MVA, all the magnetic field coil power supplies and high voltage power supplies of auxiliary heating system. The control system of power supply should make sure the large amount of on-site equipment and facilities to operate steadily and reliably. This paper presents the architecture of HL-2M control system and four kinds of established control networks. It describes how the power supply control system is built by using the established hardware structures and software agreements. Specially, it is focused on introducing an application of real-time technology based on the reflective shared memory and the fully digital compact solution for controlling the high power converters. Otherwise, a scheme which adopts PROFINET and Sequence of Events technology to carry out the intellect interlock control system is given

  18. Design of the HL-2M power supply control system

    Yao, Lieying, E-mail: yaoly@swip.ac.cn; Li, Weibin; Chen, Yuhong; Wang, Yingqiao; Bu, Mingnan; Wang, Yali; Hu, Haotian; Xuan, Weimin

    2013-10-15

    Highlights: • The control system is structured by using four kinds of control networks. • The controlling of converter is based on the real time network and FPGA. • With use of PROFINET, the status of all components can be monitored easily. • The SoE distinguishes input signals clearly to detect the fault rapidly. -- Abstract: The power supply control system is one of the most important local control systems of HL-2M tokamak. The power supply system of HL-2M is composed of four flywheel generator sets with total capacity of 600 MVA, all the magnetic field coil power supplies and high voltage power supplies of auxiliary heating system. The control system of power supply should make sure the large amount of on-site equipment and facilities to operate steadily and reliably. This paper presents the architecture of HL-2M control system and four kinds of established control networks. It describes how the power supply control system is built by using the established hardware structures and software agreements. Specially, it is focused on introducing an application of real-time technology based on the reflective shared memory and the fully digital compact solution for controlling the high power converters. Otherwise, a scheme which adopts PROFINET and Sequence of Events technology to carry out the intellect interlock control system is given.

  19. A Control Strategy for Single-phase Grid-Connected Inverter with Power Quality Regulatory Function

    Luo Ling

    2013-07-01

    Full Text Available A single-phase grid-connected inverter system based on LCL filter is established,which combines the features of inverter and active power filter. A composite control strategy for grid-connected inverter with the function of implementing reactive power compensation and harmonic compensation in the grid-connected power generation is proposed. Firstly, grid-connected inverter system structure and model is analyzed. A quasi-Proportional Resonant control method to gain the control of grid-connected fundamental wave current containing reactive power compensation current as well as the control of harmonic compensation currents is put forward; then the calculation methods of  composite control command current based on both second order generalized integrator-quadrature signal generator (SOGI-QSG and instantaneous reactive power theory are given. Finally, the effectiveness of the control strategy proposed in this paper is verified by simulation.

  20. Model-free adaptive control of advanced power plants

    Cheng, George Shu-Xing; Mulkey, Steven L.; Wang, Qiang

    2015-08-18

    A novel 3-Input-3-Output (3.times.3) Model-Free Adaptive (MFA) controller with a set of artificial neural networks as part of the controller is introduced. A 3.times.3 MFA control system using the inventive 3.times.3 MFA controller is described to control key process variables including Power, Steam Throttle Pressure, and Steam Temperature of boiler-turbine-generator (BTG) units in conventional and advanced power plants. Those advanced power plants may comprise Once-Through Supercritical (OTSC) Boilers, Circulating Fluidized-Bed (CFB) Boilers, and Once-Through Supercritical Circulating Fluidized-Bed (OTSC CFB) Boilers.

  1. Evaluation of Current Controllers for Distributed Power Generation Systems

    Timbus, Adrian; Liserre, Marco; Teodorescu, Remus;

    2009-01-01

    This paper discusses the evaluation of different current controllers employed for grid-connected distributed power generation systems having variable input power, such as wind turbines and photovoltaic systems. The focus is mainly set on linear controllers such as proportional-integral, proportio......This paper discusses the evaluation of different current controllers employed for grid-connected distributed power generation systems having variable input power, such as wind turbines and photovoltaic systems. The focus is mainly set on linear controllers such as proportional....... First, in steady-state conditions, the contribution of controllers to the total harmonic distortion of the grid current is pursued. Further on, the behavior of controllers in the case of transient conditions like input power variations and grid voltage faults is also examined. Experimental results in...

  2. Evaluation of power control with different electrical and control concept of wind farm

    Margaris, Ioannis; Hansen, Anca Daniela

    This report investigates the impact of wind power in non interconnected power systems with increasing wind power penetration. Issues such as power fluctuations, short circuits and FRT capability of wind turbines and frequency control support are under focus. The study case of Rhodes power system ...

  3. Power flow control using distributed saturable reactors

    Dimitrovski, Aleksandar D.

    2016-02-13

    A magnetic amplifier includes a saturable core having a plurality of legs. Control windings wound around separate legs are spaced apart from each other and connected in series in an anti-symmetric relation. The control windings are configured in such a way that a biasing magnetic flux arising from a control current flowing through one of the plurality of control windings is substantially equal to the biasing magnetic flux flowing into a second of the plurality of control windings. The flow of the control current through each of the plurality of control windings changes the reactance of the saturable core reactor by driving those portions of the saturable core that convey the biasing magnetic flux in the saturable core into saturation. The phasing of the control winding limits a voltage induced in the plurality of control windings caused by a magnetic flux passing around a portion of the saturable core.

  4. Response Based Emergency Control System for Power System Transient Stability

    Huaiyuan Wang; Baohui Zhang; Zhiguo Hao

    2015-01-01

    A transient stability control system for the electric power system composed of a prediction method and a control method is proposed based on trajectory information. This system, which is independent of system parameters and models, can detect the transient stability of the electric power system quickly and provide the control law when the system is unstable. Firstly, system instability is detected by the characteristic concave or convex shape of the trajectory. Secondly, the control method is...

  5. A wirelessly powered and controlled device for optical neural control of freely-behaving animals

    Wentz, Christian T.; Bernstein, Jacob G.; Monahan, Patrick; Guerra, Alexander; Rodriguez, Alex; Boyden, Edward S.

    2011-08-01

    Optogenetics, the ability to use light to activate and silence specific neuron types within neural networks in vivo and in vitro, is revolutionizing neuroscientists' capacity to understand how defined neural circuit elements contribute to normal and pathological brain functions. Typically, awake behaving experiments are conducted by inserting an optical fiber into the brain, tethered to a remote laser, or by utilizing an implanted light-emitting diode (LED), tethered to a remote power source. A fully wireless system would enable chronic or longitudinal experiments where long duration tethering is impractical, and would also support high-throughput experimentation. However, the high power requirements of light sources (LEDs, lasers), especially in the context of the extended illumination periods often desired in experiments, precludes battery-powered approaches from being widely applicable. We have developed a headborne device weighing 2 g capable of wirelessly receiving power using a resonant RF power link and storing the energy in an adaptive supercapacitor circuit, which can algorithmically control one or more headborne LEDs via a microcontroller. The device can deliver approximately 2 W of power to the LEDs in steady state, and 4.3 W in bursts. We also present an optional radio transceiver module (1 g) which, when added to the base headborne device, enables real-time updating of light delivery protocols; dozens of devices can be controlled simultaneously from one computer. We demonstrate use of the technology to wirelessly drive cortical control of movement in mice. These devices may serve as prototypes for clinical ultra-precise neural prosthetics that use light as the modality of biological control.

  6. Power factor correction, controlling voltage distortion

    A. Ceclan

    2008-05-01

    Full Text Available This paper presents, an approach fordetermining optimal sizes of single-tuned passiveharmonic filters among existent capacitor busses ina power system. The proposed method uses EdsaHarmonics Analysis and the obtained results arepresented in detail.

  7. Aspects on Dynamic Power Flow Controllers and Related Devices for Increased Flexibility in Electric Power Systems

    Johansson, Nicklas

    2011-01-01

    This thesis studies different aspects of Flexible AC Transmission System (FACTS) devices which are used to improve the power transfer capability and increase the controllability in electric power systems. In the thesis, different aspects on the usage and control of Dynamic Power Flow Controllers (DPFC) and related FACTS devices are studied. The DPFC is a combination of a Phase Shifting Transformer (PST) and a Thyristor Switched Series Capacitor (TSSC)/Thyristor Switched Series Reactor (TSSR)....

  8. EDITORIAL: Power is nothing without control Power is nothing without control

    Demming, Anna

    2012-04-01

    China have shown that they can fabricate well aligned arrays of ZnO nanorods as long as 10 μm by using a preheating hydrothermal treatment [5.] The dimensions and orientations of the nanorod arrays are particularly well suited to technological applications. Researchers in the US have enhanced the gas-sensing performance of SnO2 single-crystal nanostructures by fabricating nanowires with a segmented morphology [6]. The low-diameter sections allow an optimum ratio of the radius to the Debye length. At the same time, the structures are sufficiently robust to avoid the problems associated with manipulating extremely narrow nanowires. It has been suggested that differences in fabrication methods such as annealing parameters can affect the photoluminescence from silicon quantum dots. Hao and Shen from Shanghai Jiao Tong University in China combined their data on silicon dots annealed in oxygen with that of silicon dots annealed in hydrogen and argon and used analysis of the results to identify the photoluminescence mechanism [7]. The work shows how annealing can be used to control photoluminescence properties by modifying the defect density through annealing treatment. Defects play an important role in tailoring the properties of graphene to maximise the materials potential in electronics and spintronics. Atomistic simulations of these sorts of systems can face problems due to the shear size of the calculations. Researchers in Brazil integrated a number of modelling approaches to propose a true spin filter based on realistic boron-doped zigzag singly hydrogen passivated graphene nanoribbons up to 450 nm in length [8]. The authors explain the excellent spin filtering performance in terms of different scattering probabilities at the impurity site for majority and minority spins, which consequently leads to different localization lengths. Carbon-based nanomaterials have catalysed enormous activity in nanoscale science and technology research. As Journet et al describe in their

  9. Biasing Circuits for Voltage Controlled GSM Power Amplifiers

    van Bezooijen, André; Prikhodko, Dima; Van Roermund, A.H.M.

    2003-01-01

    In GSM phones voltage controlled power amplifiers are used to vary the output power.Inaccuracies in output power levels are predominantly caused by drift in PA gain over temperature and input power.In this paper we present biasing circuits that implement an inherently accurate gain control curve.These circuits are based on temperature stabilised V/I-converters and current mirrors.Applying current driven biasing of the first RF-stage reduces the input power dependency of the gain.Measurements ...

  10. Use of Local Dynamic Electricity Prices for Indirect Control of DER Power Units

    Nørgård, Per Bromand; Isleifsson, Fridrik Rafn

    2013-01-01

    The regulation capability that may be provided by the individual small-scale distributed energy resources (DER power units) may be insignificant. However, the aggregated response from a large number of DER power units can be significant and thereby provide valuable system services to the power...... electricity prices for indirect control of active power. The local, dynamic electricity prices are realised as dynamic adjustments of the quasi-stationary global power price. The aims of the dynamic price adjustments are to prevent overloading of the grid, to reduce the grid power losses and to regulate the...... wind power, solar power, flexible load and electrical storage. The local power price generation is based on the actual Nord Pool DK2 Spot prices on hourly basis as the quasi-stationary global electricity price, and the local SYSLAB's power exchange with the national grid as basis for the dynamic price...

  11. A Fuzzy Control System of Turbine Rotate Speed and Power for a Power Plant Simulator

    史小平; 王子才

    2002-01-01

    In this paper, a fuzzy control system of turbine rotate speed and power for a power plant simulator is designed. Rotate speed and power control is a rather important technique in a thermal power plant, because the rotate speed of the turbine rotor and the power of the generator must be enhanced gradually in order to prevent the relative expansion of the cylinder from increasing abruptly. The two parameters of a turbine used to be controlled manually or manual-automatically. To improve the control quality and the automation level, a fuzzy control method is developed for apower plant simulator to fit the DCS (Distributed Control System). The results of practical debugging on the simulator are shown in the paper to demonstrate the correctness and effectiveness of the presented fuzzy control law.

  12. Modelling Supervisory Controller for Hybrid Power Systems

    Pereira, Alexandre De Lemos; Bindner, H.; Lundsager, P.;

    1999-01-01

    The modular concept described in this paper attempts to design standard supervisory controllers for different applications. The functional abstraction hierarchy technique is used to formulate the control requirements and identify the functions of the control system. The modular algorithm is generic...

  13. Automatic control of nuclear power plants

    The fundamental concepts in automatic control are surveyed, and the purpose of the automatic control of pressurized water reactors is given. The response characteristics for the main components are then studied and block diagrams are given for the main control loops (turbine, steam generator, and nuclear reactors)

  14. Preventive and emergency control of power systems

    Wehenkel, Louis; Ruiz-Vega, Daniel; Ernst, Damien; Pavella, Mania

    2005-01-01

    A general approach to real-time transient stability control is described, yielding various complementary techniques: pure preventive, open loop emergency, and closed loop emergency controls. The organization of the resulting control schemes is then revisited in order to make it able to cover static and voltage security, in addition to transient stability. Distinct approaches for preventive and emergency operating conditions are advocated.

  15. Development of Power Controller System based on Model Reference Adaptive Control for a Nuclear Reactor

    The Reactor TRIGA PUSPATI (RTP)-type TRIGA Mark II was installed in the year 1982. The Power Controller System (PCS) or Automated Power Controller System (APCS) is very important for reactor operation and safety reasons. It is a function of controlled reactivity and reactor power. The existing power controller system is under development and due to slow response, low accuracy and low stability on reactor power control affecting the reactor safety. The nuclear reactor is a nonlinear system in nature, and it is power increases continuously with time. The reactor parameters vary as a function of power, fuel burnup and control rod worth. The output power value given by the power control system is not exactly as real value of reactor power. Therefore, controller system design is very important, an adaptive controller seems to be inevitable. The method chooses is a linear controller by using feedback linearization, for example Model Reference Adaptive Control. The developed APCS for RTP will be design by using Model Reference Adaptive Control (MRAC). The structured of RTP model to produce the dynamic behaviour of RTP on entire operating power range from 0 to 1MWatt. The dynamic behavior of RTP model is produced by coupling of neutronic and thermal-hydraulics. It will be developed by using software MATLAB/Simulink and hardware module card to handle analog input signal. A new algorithm for APCS is developed to control the movement of control rods with uniformity and orderly for RTP. Before APCS test to real plant, simulation results shall be obtained from RTP model on reactor power, reactivity, period, control rod positions, fuel and coolant temperatures. Those data are comparable with the real data for validation. After completing the RTP model, APCS will be tested to real plant on power control system performance by using real signal from RTP including fail-safe operation, system reliable, fast response, stability and accuracy. The new algorithm shall be a satisfied

  16. System defense mechanisms in nuclear power generation control computers

    Dual-redundant computers are used to control and monitor the production of power from Ontario Hydro's nuclear power reactors. Each computer must have the capability of monitoring its own performance and detecting faults. Upon fault detection, each computer must initiate corrective responses to ensure the integrity of critical control functions. This paper reviews those features the authors have termed system defense mechanisms

  17. Adaptive voltage control in power systems modeling, design and applications

    Fusco, Giuseppe

    2006-01-01

    Large-scale power cuts in both North America and Europe emphasised the need to maintain an adequate supply of high-quality electricity. This book offers information on the relatively low-cost of doing so using self-regulating control mechanisms. It is of interest to the practising power/control engineer and to academics needing industrial inputs.

  18. Parallel power electronics filters in three-phase four-wire systems principle, control and design

    Wong, Man-Chung; Lam, Chi-Seng

    2016-01-01

    This book describes parallel power electronic filters for 3-phase 4-wire systems, focusing on the control, design and system operation. It presents the basics of power-electronics techniques applied in power systems as well as the advanced techniques in controlling, implementing and designing parallel power electronics converters. The power-quality compensation has been achieved using active filters and hybrid filters, and circuit models, control principles and operational practice problems have been verified by principle study, simulation and experimental results. The state-of-the-art research findings were mainly developed by a team at the University of Macau. Offering background information and related novel techniques, this book is a valuable resource for electrical engineers and researchers wanting to work on energy saving using power-quality compensators or renewable energy power electronics systems. .

  19. Research Reactor Power Control System Design by MATLAB/SIMULINK

    Baang, Dane; Suh, Yong Suk; Kim, Young Ki [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Im, Ki Hong [Samsung Electronics, Suwon (Korea, Republic of)

    2013-07-01

    In this study it is presented that MATLAB/SIMULINK can be efficiently used for modeling and power control system design for research reactors. The presented power control system deals with various functions including reactivity control, signals processing, reactivity calculation, alarm request generation, etc., thus it is required to test all the software logic using proper model for reactor, control rods, and field instruments. In MATLAB/SIMULINK tool, point kinetics, thermal model, control absorber rod model, and other instrument models were developed based on reactor parameters and known properties of each component or system. The software for power control system was invented and linked to the model to test each function. From the simulation result it is shown that the power control performance and other functions of the system can be easily tested and analyzed in the proposed simulation structure.

  20. Research Reactor Power Control System Design by MATLAB/SIMULINK

    In this study it is presented that MATLAB/SIMULINK can be efficiently used for modeling and power control system design for research reactors. The presented power control system deals with various functions including reactivity control, signals processing, reactivity calculation, alarm request generation, etc., thus it is required to test all the software logic using proper model for reactor, control rods, and field instruments. In MATLAB/SIMULINK tool, point kinetics, thermal model, control absorber rod model, and other instrument models were developed based on reactor parameters and known properties of each component or system. The software for power control system was invented and linked to the model to test each function. From the simulation result it is shown that the power control performance and other functions of the system can be easily tested and analyzed in the proposed simulation structure

  1. Time delay control of power converters: Mixed frame and stationary-frame variants

    Blaabjerg, Frede; Loh, P.C.; Tang, Y.;

    2008-01-01

    In this paper, a mixed-frame and a stationary-frame time delay current controller are proposed for high precision reference tracking and disturbance rejection of power converters. In particular, the controllers use a proportional-resonant regulator in the stationary frame for regulating the...... controller simple implementation using mainly delay blocks, were physically tested with a digitally controlled commercial converter system....... positive and negative-sequence fundamental currents, which are known to directly influence the flow of active and reactive power in most energy conversion systems. Moreover, for the tracking or compensation of harmonics, the controllers include a time delay control path in either the synchronous or...

  2. Indirect control and power in mutual control structures

    Karos, D.; Peters, H.J.M.

    2013-01-01

    In a mutual control structure agents exercise control over each other. Typical examples occur in the area of corporate governance: firms and investment companies exercise mutual control, in particular by owning each others’ stocks. In this paper we formulate a general model for such situations. There is a fixed set of agents, and a mutual control structure assigns to each subset (coalition) the subset of agents controlled by that coalition. Such a mutual control structure captures direct cont...

  3. Control Quality of a Feedback Control System under Cyclostationary Noise in Power Line Communication

    Carrizo, Cesar; Kobayashi, Kentaro; Okada, Hiraku; Katayama, Masaaki

    This paper discusses a control system that employs a power line to transfer signals to control the motion of a single machine, and explores the influence of packet losses on the quality of the control. As an example of a controlled system, a controller with a rotary inverted pendulum as a controlled object, is considered. The feedback loop in between is the power line. The control performance is evaluated in the power line cyclostationary noise environment and compared against the performance in a stationary noise environment. As a result, it is confirmed that the power line and its cyclostationary noise features present an advantage against transmission in a channel with stationary noise.

  4. Active and reactive power in stochastic resonance for energy harvesting

    Kubota, Madoka; Takahashi, Ryo(Graduate School of Science and Engineering, Shimane University, Matsue, 690-8504, Japan); Hikihara, Takashi

    2015-01-01

    A power allocation to active and reactive power in stochastic resonance is discussed for energy harvesting from mechanical noise. It is confirmed that active power can be increased at stochastic resonance, in the same way of the relationship between energy and phase at an appropriate setting in resonance.

  5. Control strategies to optimise power output in heave buoy energy convertors

    Wave energy converter (WEC) designs are always discussed in order to obtain an optimum design to generate the power from the wave. Output power from wave energy converter can be improved by controlling the oscillation in order to acquire the interaction between the WEC and the incident wave.The purpose of this research is to study the heave buoys in the interest to generate an optimum power output by optimising the phase control and amplitude in order to maximise the active power. In line with the real aims of this study which investigate the theory and function and hence optimise the power generation of heave buoys as renewable energy sources, the condition that influence the heave buoy must be understand in which to propose the control strategies that can be use to control parameters to obtain optimum power output. However, this research is in an early stage, and further analysis and technical development is require

  6. Neural Network Predictive Control Based Power System Stabilizer

    Ali Mohamed Yousef

    2012-01-01

    The present study investigates the power system stabilizer based on neural predictive control for improving power system dynamic performance over a wide range of operating conditions. In this study a design and application of the Neural Network Model Predictive Controller (NN-MPC) on a simple power system composed of a synchronous generator connected to an infinite bus through a transmission line is proposed. The synchronous machine is represented in detail, taking into account the effect of ...

  7. Power System Stabilizer Based on Global Fuzzy Sliding Mode Control

    Nechadi, E.; Harmas, M. N.

    2013-01-01

    Power systems stability is enhanced through a novel stabiliser developed around a fuzzy sliding mode approach. First, sliding mode control is applied to selected operating point based models of a power system separately then fuzzy logic is used to form a global model encompassing the separate subsystems, thus leading to a fuzzy sliding mode power system control. Stability is insured through Lyapunov synthesis. Severe operating conditions are used in a simulation study to test the validity of...

  8. Design and Control of a Powered Transfemoral Prosthesis

    Sup, Frank; Bohara, Amit; Goldfarb, Michael

    2008-01-01

    The paper describes the design and control of a transfemoral prosthesis with powered knee and ankle joints. The initial prototype is a pneumatically actuated powered-tethered device, which is intended to serve as a laboratory test bed for a subsequent self-powered version. The prosthesis design is described, including its kinematic optimization and the design of a three-axis socket load cell that measures the forces and moments of interaction between the socket and prosthesis. A gait controll...

  9. Development of the power control system for semiconductor lasers

    For the first year plan of this program, we developed the power control system for semiconductor lasers. We applied the high-current switching mode techniques to fabricating a power control system. Then, we investigated the direct side pumping techniques with GaA1As diode laser bars to laser crystal without pumping optics. We obtained 0.5W average output power from this DPSSL. (author). 54 refs., 3 tabs., 18 figs

  10. Self-tuning constrained control of a power plant

    Problems of self-tuning digital control of a certain class of power plants are considered. A minimum variance controller with amplitude and/or introduction rate restrictions for the control signal is synthesized. The self-tuning control system is based on a prediction model, its parameters being estimated in the closed loop, using a recursive identification technique. Simulation results are presented. (author)

  11. Advanced and intelligent control in power electronics and drives

    Blaabjerg, Frede; Rodríguez, José

    2014-01-01

    Power electronics and variable frequency drives are continuously developing multidisciplinary fields in electrical engineering, and it is practically not possible to write a book covering the entire area by one individual specialist. Especially by taking account the recent fast development in the neighboring fields like control theory, computational intelligence and signal processing, which all strongly influence new solutions in control of power electronics and drives. Therefore, this book is written by individual key specialist working on the area of modern advanced control methods which penetrates current implementation of power converters and drives. Although some of the presented methods are still not adopted by industry, they create new solutions with high further research and application potential. The material of the book is presented in the following three parts: Part I: Advanced Power Electronic Control in Renewable Energy Sources (Chapters 1-4), Part II: Predictive Control of Power Converters and D...

  12. Fuzzy logic controller for automatic nuclear power plant

    In Nuclear power reactors, power stabilization is the desired goal for any reactor. During the normal operation of the reactor, different changes in its operating conditions occur such as: fuel bum-up, xenon isotope production, temperature and/or environmental changes. Therefore, an automatic nuclear power reactor control is required to compensate the reactivity changes produced by such variations. proportional-integral-derivative controller (PID), and fuzzy logic controller (FLC) schemes are discussed to achieve the optimal stabilization of power. Both PID and FLC controllers were developed as well as the reactor power plant model in order to analyze their performance. The simulation results show that FLC controller gives faster and better response. 6-16 figs., 12 refs

  13. Proceedings of power plant dynamics, control and testing symposium

    This book presents the papers given at a symposium on reactor control and monitoring systems. Topics considered at the symposium included power plant modeling and simulation, reactor simulators, power reactor surveillance by noise analysis, in core instruments, computer codes, advanced data analysis techniques, loss of coolant simulation, nuclear power plant testing, reactor safety, expert systems, applications of artificial intelligence methodology, human factors, man-machine systems, and power plant diagnostics

  14. A reduced energy supply strategy in active vibration control

    In this paper, a control strategy is presented and numerically tested. This strategy aims to achieve the potential performance of fully active systems with a reduced energy supply. These energy needs are expected to be comparable to the power demands of semi-active systems, while system performance is intended to be comparable to that of a fully active configuration. The underlying strategy is called 'global semi-active control'. This control approach results from an energy investigation based on management of the optimal control process. Energy management encompasses storage and convenient restitution. The proposed strategy monitors a given active law without any external energy supply by considering purely dissipative and energy-demanding phases. Such a control law is offered here along with an analysis of its properties. A suboptimal form, well adapted for practical implementation steps, is also given. Moreover, a number of numerical experiments are proposed in order to validate test findings

  15. Operation control device of a nuclear power plant

    If a value of a turbine generator power is within a range of a limit value, a signal of reactor thermal power is used as a feedback signal. Alternatively, if the turbine generator power exceeds the limit value, the signal of the reactor thermal power is amended depending on the deviation between the turbine generator power signal and the predetermined value of the turbine generator power, and the amended reactor thermal power signal is used as a feedback signal. Namely, if a turbine generator power is within a range of a predetermined limit value for the turbine generator power, the reactor thermal power can be controlled constantly to a predetermined value by using the reactor thermal power signal as a feedback signal relative to the predetermined value of the reactor thermal power. On the other hand, if the turbine generator power exceeds the limit value, the reactor thermal power signal as a feedback signal is amended by the deviation signal between the turbine generator power signal and a predetermined value of the turbine generator power. (N.H.)

  16. Optimization and Control of Electric Power Systems

    Lesieutre, Bernard C.; Molzahn, Daniel K.

    2014-10-17

    The analysis and optimization needs for planning and operation of the electric power system are challenging due to the scale and the form of model representations. The connected network spans the continent and the mathematical models are inherently nonlinear. Traditionally, computational limits have necessitated the use of very simplified models for grid analysis, and this has resulted in either less secure operation, or less efficient operation, or both. The research conducted in this project advances techniques for power system optimization problems that will enhance reliable and efficient operation. The results of this work appear in numerous publications and address different application problems include optimal power flow (OPF), unit commitment, demand response, reliability margins, planning, transmission expansion, as well as general tools and algorithms.

  17. Evaluation of harmonic detection methods for active power filter applications

    Asiminoaei, Lucian; Blaabjerg, Frede; Hansen, Steffan

    2005-01-01

    In the attempt to minimize the harmonic disturbances created by the non-linear loads the choice of the active power filters comes out to improve the filtering efficiency and to solve many issues existing with classical passive filters. One of the key points for a proper implementation of an active...... filter is to use a good method for current/voltage reference generation. There exist many implementations supported by different theories (either in time- or frequency-domain), which continuously debate their performances proposing ever better solutions. This paper gives a survey of the common used...... theories. Then, the work here proposes a simulation setup that decouples the harmonic reference generator from the active filter model and its controller. In this way the selected methods can be equally analyzed and compared with respect to their performance, which helps anticipating possible...

  18. CONTROLLER DESIGN FOR HYBRID POWER SYSTEMS

    N. Prabhu; R.Balraj,; S.Ayyubh

    2015-01-01

    In this paper an efficient design along with modeling and simulation of a transformer-less small-scale centralized AC—bus Connected Hybrid (Wind–PV) power system for supplying electric power to a single phase load. The main components of the hybrid system are: a PV generator (PVG); and an array of horizontal-axis, fixed pitch, small-size, variable-speed wind turbines (WTs) with direct-driven permanent magnet synchronous generator (PMSG) having an embedded uncontrolled bridge recti...

  19. Integrated low power digital gyro control electronics

    M'Closkey, Robert (Inventor); Challoner, A. Dorian (Inventor); Grayver, Eugene (Inventor); Hayworth, Ken J. (Inventor)

    2005-01-01

    Embodiments of the invention generally encompass a digital, application specific integrated circuit (ASIC) has been designed to perform excitation of a selected mode within a vibratory rate gyroscope, damping, or force-rebalance, of other modes within the sensor, and signal demodulation of the in-phase and quadrature components of the signal containing the angular rate information. The ASIC filters dedicated to each channel may be individually programmed to accommodate different rate sensor designs/technology or variations within the same class of sensors. The ASIC architecture employs a low-power design, making the ASIC, particularly suitable for use in power-sensitive applications.

  20. Digital signal processing in power electronics control circuits

    Sozanski, Krzysztof

    2013-01-01

    Many digital control circuits in current literature are described using analog transmittance. This may not always be acceptable, especially if the sampling frequency and power transistor switching frequencies are close to the band of interest. Therefore, a digital circuit is considered as a digital controller rather than an analog circuit. This helps to avoid errors and instability in high frequency components. Digital Signal Processing in Power Electronics Control Circuits covers problems concerning the design and realization of digital control algorithms for power electronics circuits using