High efficiency implementation of constant voltage control of LC/S compensated wireless charging system for stationary electrical vehicles

Abstract

In this paper, a high efficiency implementation of constant voltage (CV) control of wireless charging system with LC/S compensation is proposed for stationary electrical vehicles. The LC/S compensation network is designed based on constant current (CC) design procedure with zero phase angle (ZPA). In the receiver side, semi-bridgeless rectifier (SBR) and pulse density modulation (PDM) control are both implemented to provide CV output without wireless communication devices. With the use of SBR topology and the implementation of the PDM control strategy for SBR switches, the soft-switching operation of SBR switches is also provided. Thus, the efficiency of the CV control mode is improved in a wide range of load. The experimental results of a 1.05 kW prototype are provided to demonstrate the effectiveness of the proposed system. The peak efficiency of the system is obtained 91.9% at full load condition. In experiment, the performance comparison of PDM control with phase-shift (PS) control method is also carried out for the proposed wireless charging system. The overall efficiency of the system with PDM control is significantly improved compared to PS control at light load conditions.