Multiparallel and Flexible Expansion of Single-Switch WPT Inverter by Magnetic Integration

Aiming at the problem that the single-switch inverter for wireless power transmission circuit cannot realize the parallel connection of three or more inverters, a scheme that can arbitrarily expand the number of parallel inverters by changing the circuit structure is proposed. In this article, the current sharing coil (InterCell Transformer) is used to share the current between the branches to improve the system's stability. By adding a current-increasing LC resonant network, the output voltage can be adjusted more flexibly, and the system volume can be reduced by applying the principle of magnetic integration. Then, the complex frequency-domain model is innovatively used to accurately express the single-switch inverter circuit, which is conducive to the equivalent analysis of its various derived circuits. Finally, a parallel experimental prototype is built. When the output voltage is 164 V and the current is 11 A, the maximum efficiency is 92.1%. The experimental results show that the scheme is reasonable, feasible, and reliable.