Study on Secondary Side Control of Wireless Power Transfer Based on LCC Compensation

For the wireless power transfer system with time-varying coil position, which control method should be adopted to improve the stability of output power is a difficult problem. This paper makes a comparative study between PI (Proportional integral)+ feedforward filtering control and OCC (One cycle control). It shows that OCC has better performance. Firstly, the LCC compensation network is selected and modeled by fundamental analysis. Secondly, secondary side short-circuit decoupling control strategy is introduced. Finally, the secondary side current is introduced into PI control as feedforward quantity and diode current is introduced into OCC as the integral variable respectively. Through simulation, the effect of two control methods are compared and analyzed. The simulation results show that the OCC can significantly improve the stability of output power compared with the PI+ feedforward control under the condition of variable mutual inductance.