A Shared Charging Channel for Power and Auxiliary Batteries in Electric Vehicles

Abstract

In electric vehicles (EVs), the wireless charging system (WCS) for the high-voltage (HV) power battery and the auxiliary power module (APM) for the low-voltage (LV) auxiliary battery possess some similar power conversion stages. This letter proposes an integrated solution for WCS and APM with the shared magnetic coupler, compensation network, and power electronics converter. The coupling coil for APM is incorporated with reverse windings so as to couple with the receiving coil but decouple with the transmitting coil of the WCS system. Thus, it forms magnetic couplers for APM. The proposed system can work in the mode where WCS and APM are in operation with power from the power grid, or in the mode where APM is in operation with power from the HV battery to the LV battery. The integration of WCS and APM can reduce its weight and cost and improve the power density of the EV charging system. The experimental results have proved the effectiveness of the proposal.