Certain investigations on bridgeless isolated power factor correction converter

Abstract

New recommendations and future standards have increased the interest in Power Factor Correction PFC circuits Achieving high conversion efficiency has been a significant challenge for single phase PFC topologies Low efficiency in these PFC converters can be attributed to the high voltage and current stresses imposed on switches and other circuit components Furthermore in many cases in order to achieve proper input current shaping circulating the current through the converter which causes excessive conduction losses To solve this problem the proposed research designed a bridgeless isolated power factor correction converter which is implemented in LED products The proposed research presents a new PFC based BL Isolated Flyback Converter BL IFC for LED products In this work to improve the efficiency of traditional IFC BL configuration is introduced The front end FWR is eliminated in this configuration which reduces the conduction losses associated with them The designed converter consists of two power switches that operate in alternative halves of the line cycle such as positive and negative The proposed PFC based BL IFC is able to operate properly in CCM DCM and CRM Thus the proposed circuit can function in any of these modes to fit the intended application For DCM and CRM only output voltage control loop is required and does not require input current or voltage sensing Because of these benefits the BL IFC circuit is analyzed in DCM and CRM newline