Series compensated step-down AC voltage regulator using AC chopper with transformer

This paper describes step-down AC voltage regulator using AC chopper and auxiliary transformer which is series connected to main input. Detail design of the AC regulator, logic and PWM pattern of the AC chopper is described and three-phase AC regulator using two single-phase AC chopper with three transformers configuration is proposed for three-phase application. The proposed three-phase system has advantages of system cost due to reduced switch number and gate driver circuit and it has advantages of size and weight because it uses a series compensated scheme. The proposed AC regulator has many advantages such as fast voltage control, high efficiency and simple control logic. Experimental results show that it can be used as step-down AC voltage regulator for power saving purpose very efficiently.