An Investigation on Coil-Splitting Based Multi-Channel Wireless Power Transfer

This article proposes an input-parallel-output-parallel (IPOP) Series-Series (SS) type circuit topology structure based on a designed splitting coil coupler. By designing several transmission channels, this wireless power transfer (WPT) system has more ability on power transfer with a relatively high efficiency. The theory of enabling balanced transmission of multi-channel is derived, and the inductance relationship expression for balanced transmission of electrical energy is obtained, thus achieving balanced transmission by multi channels. Besides, by designing splitting coils, the anti-offset performance of multi-channel coils is improved. Finally, based on the conclusions obtained above, simulations of balanced transfer and anti-offset performance about design WPT system is conducted. This new design can better enhance anti-offset performance and reduce current stress while maintaining balanced transmission. Finally, theoretical analysis is proved correct through experiments with a output power of 3.3kW, and the efficiency of this prototype can reach 95.7%.