AN EFFICIENT SWITCHED-REACTOR-BASED STATIC VAR COMPENSATOR

A new static var compensator is presented in this paper. To overcome the problems of large low-order harmonics and slow response associated with conventional thyristor-controlled-reactor based compensators, a pulse-width-modulated (PWM) ac converter is used to control the reactances of switched reactors. Yet unlike the PWM static var compensators previously reported in the literature, the proposed compensator has a simpler structure and its gating signals are easier to implement. Moreover, it does not require synchronization with the ac mains. The proposed concept was verified rough a 1-kvar prototype and the measured experimental results prove that either leading or lagging reactive power can be achieved through simply duty cycle control.