A Comparison of Heuristic Methods for Optimum Power Flow Considering Valve Point Effect

Optimum Power Flow (OPF) is one of the key considerations for planning, generation control and management of electric utility. Hence it is of major importance to solve OPF with minimum cost within reasonable computing time. This paper presents solutions of OPF with Valve Point Effect (OPF-VPE) using Genetic Algorithm (GA), Differential Evolution (DE), Particle Swarm Optimization (PSO) and Artificial Bee Colony (ABC). When steam valve starts to open in a turbine it changes generation curve. The valve point effect is considered by adding sine component to the quadratic cost function for OPF-VPE. Also, penalty function is added for generator violations. The common parameters of algorithms such as population size and the iteration number are selected same values for the comparison of algorithms for solving OPFVPE. Specific parameters are stated and used for each algorithm. The heuristic algorithms are examined on IEEE-30 bus system and convergence curves are demonstrated with the system results. Performances of each algorithm are discussed as regards optimizing fuel cost, iteration time and other system results

Computational intelligence applied to power generation dispatch.

Imperial Users onl

THE BEHAVIOUR OF TSR-BASED SVC AND TCR-BASED SVC INSTALLED IN AN INFINITE BUS SYSTEM

AIAA 47th Aerospace Sciences Meeting and Exhibit -- JAN 05-08, 2009 -- Orlando, FLWOS: 000265073200025In this paper, effects of both Thyristor Switched Reactor-based Static VAr Compensator (TSR-based SVC) and Thyristor Controlled Reactor-based Static VAr Compensator (TCR-based SVC), which are two of shunt Flexible AC Transmission Systems (FACTS) devices, on load voltage in a single-machine infinite bus (SMIB) system are investigated. The modeling and simulation of TSR-based SVC and TCR-based SVC are verified using the Matlab7.04 (R) SimPowerSystems Blockset. A six-pulse generator is used to control of TSR in the SVC. A fuzzy logic controller is used to control of TCR-based SVC. The studied power system consists of a synchronous generator connected to an infinite bus and a static load. The results show that improvement on reactive power compensation and load bus voltage regulation could be achieved by using the TSR-based SVC and TCR-based SVC.Amer Inst Aeronaut & Astronau

PI CONTROL OF THYRISTOR SWITCHED CAPACITOR (TSC) AND THYRISTOR SWITCHED REACTOR-BASED STATIC VAr COMPENSATOR (TSR-BASED SVC)

WOS: 000273608300006Together with the improvement in current and voltage handling capacities of power electronic devices, different type controllers have been increasingly used for efficient shunt and series compensation. The most promising controllers based on power electronics are known as Flexible AC Transmission Systems (FACTS) devices. In this study, the effects of two of shunt FACTS devices, which are Thyristor Switched Capacitor (TSC) and Thyristor Switched Reactor (TSR)-based Static VAr Compensator (SVC) on load bus voltage are investigated. Six Pulse Generator and PI Controller are used to control firing angles of TSC and TSR-based SVC. These compensators are simulated by using Matlab/Simulink, Power Systems Toolbox. Analyzed the studied three phase power system consists of two buses, a static load and a long transmission line model. The simulation results show that PI controller can be easily applicable to these type compensators

Experimental studies of a scaled-down TSR-based SVC and TCR-based SVC prototype for voltage regulation and compensation

WOS: 000277173800001In this paper, prototypes of two shunt flexible AC transmission system (FACTS) devices, a thyristor switched reactor (TSR)-based static VAr compensator (SVC) and a thyristor controlled reactor (TCR)-based static VAr compensator- have been developed. The design and testing of both a TSR-based SVC and a TCR-based SVC are accomplished in the Power Systems Research Laboratory of Nigde University. The TSR-based SVC and TCR-based SVC devices are studied in three-bus and single machine infinite bus systems for three-phase static load conditions. The effects of TSR-based SVC and TCR-based SVC devices on load voltages are also analyzed. Experimental results show that significant improvement in reactive power compensation and voltage regulation is achieved by using TSR-based SVC and TCR-based SVC.Scientific & Technological Research Council of Turkey [TUBITAK 104M235]This work was supported in part by The Scientific & Technological Research Council of Turkey under the project number TUBITAK 104M235

The modeling and simulation of thermal based modified solid oxide fuel cell (SOFC) for grid-connected systems

This paper presents a thermal based modified dynamic model of a Solid Oxide Fuel Cell (SOFC) for grid-connected systems. The proposed fuel cell model involves ohmic, activation and concentration voltage losses, thermal dynamics, methanol reformer, fuel utilization factor and power limiting module. A power conditioning unit (PCU), which consists of a DC-DC boost converter and a DC-AC voltage-source inverter (VSI), their controller, transformer and filter, is designed for grid-connected systems. The voltage-source inverter with six Insulated Gate Bipolar Transistor (IGBT) switches inverts the DC voltage that comes from the converter into a sinusoidal voltage synchronized with the grid. The simulations and modeling of the system are developed on Matlab/Simulink environment. The performance of SOFC with converter is examined under step and random load conditions. The simulation results show that the designed boost converter for the proposed thermal based modified SOFC model has fairly followed different DC load variations. Finally, the AC bus of 400 Volt and 50 Hz is connected to a single-machine infinite bus (SMIB) through a transmission line. The real and reactive power managements of the inverter are analyzed by an infinite bus system. Thus, the desired nominal values are properly obtained by means of the inverter controller.

Robust Design using Pareto type optimization: A genetic algorithm with arithmetic crossover

WOS: 000257535700014In dual response systems (DRSs) optimization restrictions on the secondary response may rule out better conditions, since an acceptable value for the secondary response is usually unknown. In fact, process conditions that result in a smaller standard deviation are often preferable. Recently, several authors stated that the standard deviation of any performance property could be treated as a new property in its own right as far as Pareto optimizer was concerned. By doing this, there will be many alternative solutions (i.e., the trade-offs between the mean and standard deviation responses) of the DRS problem and Pareto optimization can explore them all. Such analysis is useful, and that is required in order to achieve an improved understanding of the problem before searching for a final optimal solution. In this paper, we again follow this new philosophy and solve the DRS problem by using a genetic algorithm with arithmetic crossover. The genetic algorithm is applied to the printing process problem for improving the quality of a printing process. Genetic algorithms, in contrast to the one-solution-at-a-time approach of most optimization algorithms, maintain a population of hundreds, or thousands, of solutions in speedy manner. (C) 2007 Elsevier Ltd. All rights reserved

Experimental Studies of a Scaled-Down TSC Prototype for Voltage Regulation and Compensation

WOS: 000276044700010In this paper, a prototype of Thyristor Switched Capacitor (TSC), which is one of shunt Flexible AC Transmission Systems (FACTS) devices, has been developed The design and testing of TSC are verified in the Power Systems Research Laboratory at Nigde University. The TSC device is studied at two-bus, three-bus and single machine infinite bus (SMIB) systems for three-phase static load conditions. The effects of the TSC device on load voltages are also analyzed The experiment results show that significant improvement on reactive power compensation and voltage regulation is achieved by using TSC. Copyright (C) 2010 Praise Worthy Prize S.r.l. - All rights reserved.Turkish Scientific and Technical Research Council (TUBITAK) [TUBITAK 104M235]This work was supported in part by the Research Fund of the Turkish Scientific and Technical Research Council (TUBITAK) under the project number of TUBITAK 104M235

THE BEHAVIOR OF THYRISTOR SWITCHED CAPACITOR (TSC) INSTALLED IN AN INFINITE BUS SYSTEM

International IEEE Conference Devoted to the 150-Anniversary of Alexander S Popov -- MAY 18-23, 2009 -- St Petersburg, RUSSIAWOS: 000272589500101This paper examines the effects of Thyristor Switched Capacitor (TSC) on load voltage in a single-machine infinite bus (SMIB) system. The modeling and simulation of TSC are verified using the Matlab/Simulink 7.04@ and SimPowerSystems Blockset. The studied power system consists of a synchronous generator connected to an infinite bus and a static load. The results show that improvement on reactive power compensation and load bus voltage regulation could be achieved by using the TSC. Also, the test system with TSC is not needed a harmonic filter and low frequency voltage oscillations are damped by using TSC.IEE