Dual closed loop control of LLC resonant converter for EV battery charger

In this paper, LLC resonant converter simulation with dual closed loop control is demonstrated for Electric Vehicles (EVs) battery charger. To improve efficiency and fast charging conditions, switching losses must be diminished to have a maximum energy transfer among the variable converter components. The presented dual closed loop control technique is implemented under soft-switching conditions with constant current and constant voltage control methods. The designed DC/DC resonant converter, fed by Power Factor Corrector (PFC) outputs 200-300 V, provides 60 V/20 A at 1.2 kW. The simulation results show that differences in soft switching conditions are obtained by realizing input current and input voltage in phase under different output load conditions. At the same time, a battery is charged using Constant Current (CC) and Constant Voltage (CV) control techniques.