Solid state flicker controller using a pulse width modulated AC-AC converter

Flicker at load locations is primarily caused by cyclically and randomly varying loads. Mitigation of flicker has always been a challenging task due to the speed of response necessary for the intervening device to perform the correcting action. Recent developments in technology of pulse width modulated (PWM) AC to AC converters make it possible to realize a fast acting variable reactance, which can be used for flicker control. The development of such a solid-state flicker controller, accomplished by using a PWM buck AC to AC power converter to interface between the AC line and a capacitor bank is presented in this paper. The paper presents a detailed discussion of the principles of operation and design equations. Simulation results verifying the operation of the proposed approach and experimental results that demonstrate the feasibility are also presented.