Synchronous Tuning of Self-Oscillating for Electrical Coupled Bidirectional Wireless Power Transfer System

Electrical Coupled Bidirectional Wireless Power Transfer System (EC-BWPT) system has gradually attracted attention due to the unique advantages of transferring power through metal barriers, lightweight structure, which achieving bidirectional wireless power transmission between the power grid and electrical equipments. However, due to the high operating frequency of the EC-BWPT system, frquency and phase synchronization of the primary and secondary independent controllers is crucial for achieving precise bidirectional power transmission. This paper proposes a self-oscillation synchronous tuning control technology for the bilateral LCLC resonant network EC-BWPT system, the stable ZVS operating points of self-oscillating are derived by stroboscopic mapping and Poincare mapping models, and then the controllers driving the converters by detecting zero crossing resonant current of the primary and secondary sides. The implementation of the control method does not require PLL, VCO, complex data calculations, additional analog circuits, complex control algorithms, etc. The simulation validated the effectiveness of the proposed self-oscillation synchronous tuning control method for the proposed EC-BWPT system.