Resonant AC-AC Converter With Multi-Power Level Controller for Inductive EV Charging Systems

Design of Inductive Power Transfer (IPT) controller to tune EV charging level in a wide range is of great importance. The IPT power level controller is proposed to regulate the power transfer rate by modulating the active state and zero state counts of the converter. During active states, energy injection is applied to the IPT compensation tank which increases the IPT resonant current; during the zero state; no injection occurs, and the resonant current of IPT tank is in free oscillation. The FPGA-based IPT power controller is designed to be applied on single stage AC-AC matrix converter which allows direct connection to the main grid without any need of DC conversion; the controller is also operational in dual-stage AC-DC-AC topologies. The proposed IPT power controller is self-tuned without any need to wireless communication channel and offers more simplicity, higher speed, ease of implementation and lower cost. The efficiency up to 90.73% is achieved for the proposed IPT controller thanks to soft-switching (ZCS and ZVS). Finally, ModelSim-Quartus simulation results as well as experimental validation results are provided.