To Improve Power Transfer Capacity Using TCSC FACTS Controller

Abstract

Electrical networks are interconnected to different generating stations and load centers according to the existing plan. But load demands on the system are not constant. With the increase of industrial growth and domestic load, more power is consumed by the different loads. To fulfill the load demand, either electrical system network has to be re-evaluated or the power carrying capability of the transmission line to be increased. From economic point of view, modification or alteration of electrical network is costly. Thus the aim is to increase the power carrying capability of the transmission line. Power systems of today are mostly mechanically controlled. Mechanical switching action is slow and power flow control is not fast enough according to the load variation. Another problem of mechanical control is that it cannot be initiated frequently as it leads to wear and tear. To maintain both dynamic and steady-state operation, the new technology, i.e., FACTS (Flexible AC Transmission System) is used which is a power-electronics-based system. Its main role is to enhance controllability and power transfer capability in AC systems. FACTS technology uses switching power electronics to control power flow in the range of tens to hundreds of megawatts. In this project, it is considered about one of the Series Controller that is Thyristor-Controlled Series Capacitor (TCSC) to control the power flow in the transmission line. TCSC is one of the FACTS devices which consist of a series capacitor bank shunted by a Thyristor-Controlled Reactor (TCR) in order to provide a smoothly variable series capacitive reactance by varying the firing angle of Thyristor-Controlled Reactor (TCR). From the execution of MATLAB code, we reached at a conclusion that Thyristor-Controlled Series Capacitor is one of the fast-acting power electronic controllers which can provide current and power flow control in the transmission line by varying its firing angle. Thus Thyristor-Controlled Series Capacitor (TCSC) can be used as a series capacitor to decrease the overall transmission line reactance. Depending on the development of power transfer preferred at that time, without affecting other system-performance criteria, series compensation can be varied by Thyristor-Controlled Series Capacitor (TCSC). Thus Thyristor-Controlled Series Capacitor (TCSC) is one of the important FACTS controller, which increases the overall power transfer capacity in the transmission line.