A High Efficiency LCC-S Compensated WPT System With Dual Decoupled Receive Coils and Cascaded PWM Regulator

A LCC-S compensated wireless power transfer (WPT) system with dual decoupled receive coils and a cascaded PWM regulator is proposed in this brief. The dual decoupled receive coils, comprising of bipolar coil and unipolar coil, provide two power paths. Most of input power is transferred to load directly through bipolar coil while only small portion of input power is transferred through unipolar coil and the cascaded PWM regulator, which can reduce power loss effectively. The output voltage of WPT system is regulated by the cascaded PWM regulator, thereby wireless communication links (WCLs) is not required in the feedback control loop, which leads to simple control circuits and good stability. Compared with conventional WPT system with two-stage power conversion, it is cost-effective as voltage/current stress of PWM regulator can be significantly alleviated. Besides, the LCC-S compensated WPT system can operate under zero phase angle (ZPA) condition with low voltage-ampere rating components. A 1.5kW prototype is built and experimental results show that the system efficiency up to 93% can be achieved under full load, which is 2.3% higher than that of conventional WPT system with two stage power conversion.