The application of this converter in the AC power system in simple DVR configuration has been indicated in this paper. Further more, in combinationwith conventional transformer, they form a hybrid transformer.AC choppers have important advantages: . sinusoidal current waveforms, better power factor, faster dynamics and smaller input/output filters. The second group contains devices with galvanic separation from the electromagnetic transformer. The firsttopology is named solid state transformer and is a combination of high frequency transformer and AC–AC converter.