Simulation Study Of3.3kW Electric Vehicle Charger Based On Soft-switching Technology

Charger, as an important component of electric vehicles, converts electricity from AC to DC, so as to recharge the battery pack. This paper discusses the structure of a3.3kW electric vehicle charger, which consists of APFC and DC/DC full-bridge. The simulation has been made about the main circuit after selecting and calculating the parameters.When designing3.3kW electric vehicle charger, active power factor correction (APFC) uses the boost circuit for improving power factor and reducing the charging harmonic. Based on average current control, the control loop contains outer voltage loop and inner current loop, dual closed-loop control structure is designed.A full-bridge phase-shifted ZVZCS converter is chosen by the analysis and comparison about the main circuit topologies of DC converters. The secondary circuit adds a simple subsidiary in converter, which consists of a capacitor and two small diodes. The forward-leg and lagging-leg switches respectively achieve zero-voltage switching (ZVS) and Zero-current switching(ZCS) through the resonant of the primary main circuit and auxiliary circuit, which includes no additional active component that would make the proposed converter more efficient. According to phase-shift control, the simulation of the full-bridge ZVZCS is realized.By the help of Matlab the circuit simulation and comparison study is illustrated about battery load in actual working conditions and common resistive load in charger physical test. The results of simulation verify the main circuit parameter designs, and provide a theoretical basis for further physical prototype design of the charger.