Analysis and Design of DCM Operated Bridgeless Buck-Boost Derived PFC Converter for Plug-in Charging Application

Abstract

A novel bridgeless buck-boost derived converter is proposed with less number of semiconductor devices for onboard EV charging application. Proposed charger operates in discontinuous inductor current mode benefiting limited components for its operation and achieves natural power factor correction (PFC) at adjustable grid input supply. Also, grid input voltage and current sensing are not necessary making the charger cost effective, and rugged to high-frequency noise. Correspondingly, the control becomes simple with the use of one voltage sensor and requires only one control loop. Moreover, as the converters have fewer semiconductor devices the voltage stress on the devices is also reduced in comparison with traditional bridgeless topologies. This consequently reduces the switching losses in the semiconductor devices and meliorates gross efficiency. Furthermore, the presence of only one semiconductor device in the current flowing path over a switching cycle greatly reduces the conduction losses while also facilitates the eases of thermal management. A comprehensive steady-state analysis over one switching sequence and the design equation is presented. The proposed EV charger analysis and the design are confirmed with the simulation and experimental results which uphold the design of the proposed converter.