Output Power Control Strategy for Omnidirectional Wireless Power Transfer System Based on Maximum Mutual Inductance Information Estimation

In order to solve the problem of transmission power fluctuation and efficiency degradation of wireless power transfer system caused by the change of receiver coil position, this article proposes an omnidirectional wireless power transfer (OWPT) system output power control strategy based on online estimation of maximum mutual inductance parameters. The equivalent circuit model of the OWPT system with three-phase inductance-capacitance-capacitance-serial (LCC-S) compensation network is established, and the bivariate gradient descent method is used to search for the maximum and minimum values of dc input power, thereby estimating the maximum value of mutual inductance parameters. Based on the estimated maximum mutual inductance value and the load receiving power equation, determine the current amplitude of each transmitting coil when the required load receiving power is required. When ensuring the maximum transmission efficiency of the OWPT system, solve the problem of power fluctuations caused by the movement of the receiving coil position in the system. Finally, the feasibility of estimating the maximum mutual inductance parameters and the correctness of the output power control strategy were verified through experiments.