A Fuzzy Based Three-Level Isolated Single-Stage PFC Converter

Abstract

An improved single stage three level isolated ac/dc power factor correction (PFC) converter topology is proposed in this paper. For high dc-link voltage low-power applications, achieved through an effective integration of ac/dc and dc/dc stages, where all of the switches are shared between two operations. With the proposed converter and switching scheme, input current shaping and output voltage regulation can be achieved simultaneously without introducing additional switches or switching actions. In addition, the middle two switches are turned on under zero current in discontinuous conduction mode operation, and the upper and bottom switches are turned on under zero voltage. Due to the flexible dc-link voltage structure, high power factor can be achieved at high line voltage. This proposed system is extended with the help of fuzzy controller for better power factor improvement. And the proposed system is tested and verified using Matlab/Simulink.