Input AC side switched active filtered high performance three phase cuk rectification with energy recovery snubber

Input current and power factor improvements of single and three phase rectifiers by switch mode regulators are usually achieved by switching the output of rectifiers. The output switching makes input current high frequency switched, which is then filtered by a small filter to get low THD input current at near unity power factor. In this paper, a three phase cuk rectifier is proposed which is regulated at the input side by one three phase bi-directional switch with energy recovery snubber. Direct input current switching ensures current displacement with input voltage to be unity. This makes the control logic simpler for maintaining high input power factor and low input current THD. The efficiency is also high due to the use of energy recovery snubber. Comparisons are made with conventional cuk regulated three phase rectifier performances and improvements are demonstrated.