Research On 400Hz Input Multi-Level PFC Techniques

Abstract

Input current distortion in the vicinity of input voltage zero crossings is a major concern for conventional singlephase Boost PFC applications, especially under high ac line frequencies. This paper discusses the previously known causes for the input current distortion and points out that the multi-level power conversion technique can effectively reduce the zerocrossing distortion under high frequencies. A three-level (TL) Boost converter containing flying capacitors is then presented as the PFC topology. The system control method of the converter is also discussed. Experimental results are presented to validate the effectiveness of the proposed method