GCSC - gate controlled series capacitor: a new FACTS device for series compensation of transmission lines

Controllable series compensation is a useful technique to increase the efficiency of operation of existing transmission lines and improve overall power system stability. Up to date, the TCSC is the most adopted solution whenever controllable series compensation is required. This paper introduces the gate controlled series capacitor (GCSC), a novel FACTS device for series compensation. The principle of operation and some prospective applications of the equipment are presented. Special attention is given to the duality of the GCSC with the well-known thyristor controlled reactor, used for shunt compensation. It is shown that the GCSC can be more attractive than the TCSC in most situations. Simulation results illustrate the time response of the equipment and its ability to control power flow in a transmission line. Finally, technology issues regarding high power self commutating valves are discussed.