Reactive power compensation in AC power systems

This chapter introduces most widely used reactive power compensators considering the recent advances seen in industrial applications. In order to provide better and deeper knowledge for authors, the basic principles of reactive power compensation and symmetrical systems are presented primarily. The theoretical backgrounds are discussed by comparing each approach and application types in detail. The remainder of the chapter is organized by considering the comprehensive figure that is illustrated in the third section. Thereby, the first generation conventional compensators and lately improved FACTS are introduced in the following sections. Furthermore, the compensation devices are also listed according to their integration to transmission line as shunt, series, and shunt-series devices. The circuit diagrams and control characteristics of each compensation device are presented with its analytical expressions. The power flow control, voltage and current modifications, and stability issues are illustrated with phasor diagrams in order to create further knowledge on operation principles for each device. The comparisons are associated with similar devices and emerging technologies