Bridgeless PFC Converter Based EV Charger

This paper presents a semi-bridgeless boost (SBLB) converter fed synchronous full bridge inductor-inductor-capacitor (FBLLC) converter based electric vehicle (EV) charger. The SBLB converter forms the first stage of the EV charger, which performs dual purpose. Firstly, it eliminates harmonic components from the input line current, thereby ensuring good power quality (PQ) sinusoidal line current in phase with the supply voltage and secondly, it regulates the intermediate DC link voltage. The second stage is a DC-DC conversion stage and is accomplished by an efficient zero voltage switched (ZVS) synchronous FBLLC converter. The first stage SBLB converter operates at fixed frequency in average current control (ACM) using two loop structure. The outer loop is the DC link voltage loop, while the inner loop is the input current control loop. The control of synchronous FBLLC converter is variable frequency control (VFC) and has advanced features like ZVS. The control of this converter is a constant voltage (CV) and constant current (CC) control to charge the connected EV. An experimental proto-type of a 3kW EV charger is developed using a 60MHz digital signal processor (DSP) and the results are presented and discussed in detail.