Electric utilities are operating in an increasingly competitive market where economic and environmental pressure limits their scope to expand transmission facilities. The optimization of transmission corridors for power transfer has become of great importance. In this regard, the FACTS technology is an attractive option for increasing system operation flexibility. New developments in high current, high-power electronics are making it possible to control electronically the power flows on the high voltage side of the network during both steady state and transient operation.

One important FACTS component is the TCSC (Thyristor Controlled Series Compensator), which allows rapid and continuous changes of the transmission line impedance. The TCSC module consists of a series capacitor bank in parallel with a Thyristor Controlled reactor (TCR). The controlling element is the bi-directional thyristor valve.

In this, the state variable is the TCSC’s firing angle. In this paper, a method is presented to find a best possible location from among the available locations for placing the TCSC in any one of the lines of a transmission system so as to improve the transmission efficiency of the line, and to improve the voltage profiles, stability and stability of the system.