Wireless Power Transfer System with Variable Mutual Inductance Control for Battery Charging

In recent years, the wireless power transfer system (WPTS) has developed rapidly. However, traditional WPTS cannot handle sudden disturbances of the mutual inductance, which will have negative effects on the whole system. In this paper, a wireless power transfer system (WPTS) with variable mutual inductance control (VMIC) is proposed. The mutual inductance is one of the control variables in the system, which increases the control flexibility. On one hand, VMIC can handle random disturbances of the mutual inductance. On the other hand, VMIC can also make the system operate very close to the optimal operating curve through controlling the mutual inductance while maintaining CC/CV charging. Finally, a 105W prototype was built and experimental results verified the theoretical analysis and the validity of the control strategy.