Research of LCL Resonant Inverter in Wireless Power Transfer System

The LCL type MCWPT system in continuous current mode is analyzed in detail. The iterative model for numerical analysis of transient dynamic response is built up with discrete time mapping modeling method. It is found that when the control frequency is equal to the inherent resonant frequency of secondary side, the inverter output current has large distortion and the switches are working in hard-switching mode. Then an effective way to find out the ideal operation frequency with the impedance analysis is proposed. A parameter optimizing process is applied to the system to realize its ideal operation mode where it has the maximum power transfer capability and efficiency. Simulation results from PSpice have verified the theoretical results.