A Soft Switched Bridgeless Cuk High Power Factor Rectifier Based LEVs Charging System

A light electric vehicle (LEV) charger, based on a zero-voltage transition bridgeless high step-down gain Cuk rectifier is presented in this work. In order to obtain higher step-down gain, a switched inductor network is introduced at the output side, which enables the operation of the charger for wide AC supply voltage. Unlike some of the existing bridgeless topologies, the presented charger uses only a single switch in the main circuit, with an auxiliary switch in the resonant switch network. Moreover, the charger is capable of operating at high switching frequencies, without incurring much losses caused due to the switching of semiconductor devices. The charger operates in PWM as well as a resonant mode within each switching interval, and exhibits zero-voltage transition (ZVT), during the turn-on of the main switch, as well as zero current turn-off of the auxiliary switch, thus reducing the losses during the switching of semiconductor devices. The current through the output diode also is made to cease to zero gradually, thereby, further reducing the losses associated with the reverse recovery of the diodes. Added to these, the charger is capable of providing good battery charging profile as well as power factor correction (PFC) at the input side. A comprehensive design and simulation results of the charger for a 450W, 230V(RMS) supply and battery pack with nominal voltage of 48V are presented in this work.