International Journal of Scientific & Engineering Research, Volume 5, Issue 1, January2014 ISSN 22295518 IJSER © 2014 http://www.ijser.org Optimal placement of SVC in electrical power dis- tribution systems using Genetic Algorithm Alizaman Zamani, Mahmoud Zadehbagheri, Amin Hajizadeh Abstract— Placement of static voltage compensators and bus compensators in order to enhance the voltage is a common and fundamental issue in the power field. Nowadays, electrical systems are one of the most advanced man-made systems in terms of size, technology and price. There- fore, economical usage and optimization are very important. Developing facilities and increasing network load lead to fragile systems such that there have been some obstacles in the field of power stability due to voltage instability worldwide. One fundamental component of static voltage compensators is bus capacitor which plays an important role in static voltage instability. System loss and voltage profile are very important in optim- al resource design. Therefore, placement of the mentioned parts plays an important role in enhancing the voltage stability. In this article, genetic al- gorithm is used to enhance voltage. Stimulation results have shown that genetic algorithm is very useful. Index Terms— Reactive Power Compensation, Static VAR Compensator, Optimization, Genetic Algorithm, FACTS devices. ——————————  —————————— 1 INTRODUCTION ne of the most significant issues in power systems is reac tive power compensation. These days, FACTS tools are very important in supporting network with reactive power and promoting network voltage stability. Voltage instability in power systems occurring after global cutoff is considered as the most important concern recently. Voltage instability point is named maximum loading point. Loading increase, envi ronmental limitations and revised structure of power system lead to need for suitable control in order to maintain network stability. Load distribution control and better voltage stability are obtained using FACTS tools. SVC is a component of series reactive power compensator which is controlled according to network parameters. There are multiple methods for placing FACTS tools in power network. Hierarchical methods are among the recommended methods to place the mentioned tools traditionally. This method is performed precisely in small networks but for bigger networks, more scientific methods are required. Generally speaking, other methods such as genetic algorithm, fuzzy logic and neural networks are used to place FACTS tools. One significant application of FACTS tools is to increase system portability and to pass power through desira ble passages[1,2]. 1 Static VAR compensator Static voltage compensator is a variable Susceptance whose value can be changed in capacitor continuously. Main plan of static voltage compensator in the form of control theristor reactor is shown in figure 1 [3]. Fig.1. Thyristor controlled reactor Controller elements of two theristors are attached together is series and reverse way. Each theristor passes the current in a half cycle. If fire angle of two theristors delayed equally, reac tor current will delay also. Reactor current deviates from con tinuous status. When fire angle increases then current main component amplitude will diminish. Current decrease and fire angle increase are attributed to selfinductance increase. In this way, fire angle changes lead to selfinductance changes. There fore, a controllable Susceptance is achieved which is used as static compensator. By having a series capacitor in this assem bly, compensating Susceptance changes on the both positive and negative domains are possible in the continuous form. O ————————————————  Alizaman Zamani is with the Science and Research Branch, Islamic Azad University,Kohgilouye and BoyerAhmad,Yasouj, Iran (ali225zamani@yahoo.com)  Mahmoud Zadehbagheri is with the Islamic Azad University of Yasouj, Faculty of Engineering, Yasouj, Iran .(mzadehbagheri@gmail.com)  Amin Hajizadeh is with the University of Shahrood, Faculty of Electrical Engineering, Shahrood, Iran.( aminhajizadeh@gmail.com). 1559 IJSER