A General Equivalent Model for Multi-Coil Wireless Power Transfer System Analysis and its Application on Compensation Network Design

摘要

This paper presents a novel general equivalent model of multi-coil coupled wireless power transfer (WPT) system and its application on compensation network design. The proposed equivalent model has the advantages of concise expressions, good accuracy, and fast calculation speed. Firstly, the general equivalent model is established to get the concise expressions of system efficiency and output power. Then, based on the proposed model, compensation network design method is discussed, considering several system performance indicators. Furthermore, the proposed model and method are verified by a developed WPT prototype. Meanwhile, the equivalent characteristics and the mutual-resistance effect are analyzed. Also, numerical simulations are conducted to study the magnetic flux distribution, the magnetic field exposure issue, and the current distribution in coil Litz wire. Finally, a varied capacitor compensation method is presented to improve system efficiency on the conditions of coil misalignments.