Interoperability and Misalignment Tolerance of Electric Vehicle Wireless Charging System Based on Multiple Self-Decoupled Transmitting Coils and Vector Synthesis Strategy

In wireless power transfer (WPT) systems for electric vehicles (EVs), interoperability and misalignment tolerance for different receiving charging terminals meet great demands. In this article, a hybrid topology with a vector synthesis strategy and highly integrated magnetic couplers are proposed to achieve misalignment tolerance and interoperability for unipolar (Q), bipolar (DD), and quadrupolar (QUA) coils over the X and Y misalignments. By adjusting the phase angles of the four half-bridge inverters under different misalignments, the output voltage fluctuation can be limited. The mathematical model of the proposed hybrid topology is established and the vector synthesis strategy is introduced. The magnetic couplers and the design principle are presented. A 2-kW prototype is built to verify the proposed system. The experimental results demonstrate that the output voltage fluctuation under misalignments is less than 3.1% for the Rx Q coil, 3.3% for the Rx DD coil, and 4.3% for the Rx QUA coil, and the peak efficiency is 89.3%.