Research On Boundary Conduction Mode Totem Pole Boost Power Factor Correction Rectifier

With the advantages of high efficiency,light weight and wide regulated range,switching mode power supply is widely used in the field of communication power supply.At present,the popular scheme is generally composed of the front stage power factor correction(PFC)and the rear stage DC/DC.This paper focuses on the PFC stage.The boundary conduction mode totem-pole boost power factor correction topology is becoming popular in high efficiency and high power density communication power supply because of its advantages of less devices,low conduction losses and soft switching.However,the high inductance current peak value needs a huge different mode EMI filter.The input and output current can be significantly reduced by interleaving two boost PFC converters.Therefore,the DM EMI filter and output capacitance can be reduced,too.Another benefit of interleaving is that the efficiency at light load can be increased by employing phase shedding.However,since the switching frequency is variable,the synchronization of interleaved BCM boost PFC converters presents a challenging task.The design of high efficiency and high power density BCM totem pole boost PFC is this paper' s research object.There are analysis of control method,zero crossing detection and interleaving.In totem pole PFC,the MOSFET body diode is the freewheeling diode,which has a serve reverse recovery.And it will affect the accuracy of calculation result.In this paper,based on the reverse recovery slop process analysis method,the measurement method of the device' s reverse recovery coefficient is given.An accurate analytical method of BCM totem pole Boost PFC considering reverse recovery is proposed.According to the method,a 600W high efficiency high power density BCM totem pole Boost PFC prototype was developed and the accuracy of the method was verified.