A Hybrid Control Strategy of LCC–LCC Compensated Electric Vehicles Wireless Charging System With Wide ZVS Range

In this article, a hybrid control strategy considering zero-voltage-switching (ZVS) of the inverter within a wide load range is proposed for LCC–LCC compensated electric vehicles wireless charging system. The modified asymmetric voltage cancellation and half-bridge (HB) control modes are combined to satisfy output requirements. Based on the hybrid control strategy, constant-current and constant-voltage outputs can be easily achieved by fixed-frequency phase shift without complex control and additional auxiliary circuits. A time-domain model considering harmonics and rectifier load is developed, based on which an optimal parameter design method is presented for the hybrid control strategy to achieve ZVS and minimize circulating reactive power. Finally, a 3.3 kW experimental prototype is built to verify the feasibility of the proposed method. The results show that ZVS can be achieved over the range of 10–100% rated output power. Compared with the conventional hybrid control strategy that combines symmetric phase shift and HB control, the efficiency can be improved by 1.2–3.6% and the maximum efficiency is 94.1%.