Integrated Four-LCC-Parallel Circuit for Wireless Power Transfer of Electric Vehicles with Vector Synthesis Strategy

Misalignment tolerance is an indispensable characteristic in wireless power transfer ( WPT) systems for electric vehicles (EVs). In this paper, a multiple Tx parallel topology with a vector synthesis strategy is proposed to achieve misalignment tolerance for unipolar (Q) coil over the X and Y misalignments. The coils and compensation inductances at the Tx side are highly integrated. After modification of the phase angles of the four half-bridge inverters based on the strategy under misalignments, the output voltage fluctuation can be decreased. The mathematical model of the proposed four-LCC-parallel topology is established and the vector synthesis strategy is explained. The magnetic couplers and the design principle are presented. A 2-kW prototype is built to verify the proposed system. the output voltage fluctuation of the experiment under misalignments is less than 3.1%, and the average dc-dc efficiency is 87.5%.