Flexible AC transmission systems. III. Conventional FACTS controllers

In this tutorial FACTS controllers are examined which are commercially available, or could be developed in the short term using available hardware-conventional FACTS controllers. The distinguishing feature of conventional FACTS controllers, compared to advanced FACTS controllers, is that the former are based on the use of conventional thyristors, i.e. thyristors relying on natural commutation. The authors discuss principles of operation, the static VAr compensator, the controllable series compensator, and the turbine controlled phase shifting transformer.