Electric Power Research Institute of Guangxi Power Grid Co., Ltd., Nanning 530023, China

For the dynamic wireless charging system for electric vehicle, if the segmented control of guide rails is adopted in the switching process of guide rails, the output power and efficiency of the system will drop sharply, even far below the expected value, which cannot meet the requirements of the output power of the system. Through the transient analysis of the switching process of guide rails, this paper calculates the variation of output power when the clock pulse signals of inverter circuit(where the adjacent guide rail coils are located)have the same frequency and phase difference or the same frequency with different phase differences. It is concluded that the phase difference of clock signal of inverter circuit(where the adjacent guide coils are located)is the reason for the sudden drop of output power and efficiency during the switching process of guide rails. Then, this paper proposes a pulse synchronization control strategy for dynamic wireless charging of electric vehicles during the switching process of guide rails, which effectively improves the situation that output power and efficiency drop sharply and the system cannot operate normally. Finally, the importance of synchronous clock pulse signal and the effectiveness of the control strategy are verified by simulation and experiment.