A Hybrid Compensation Circuit Topology Based on Dual Frequency Tuning Method for Improving Misalignment Tolerance of Capacitive Power Transfer System

ABSTRACT Wireless power transfer (WPT) technology offers great convenience and flexibility in daily life, especially in charging electric vehicles (EVs). With the popularization and rapid development of EVs, it is very important to deal with output voltage and power fluctuations to improve charging efficiency and reduce transmission costs. To solve these problems, this paper proposes a hybrid compensation circuit topology (HCCT). By applying the dual‐frequency tuning method (DFTM) to the HCCT, the capacitive power transfer (CPT) system improves the resonant performance of the converter, reduces the modulation complexity, and is insensitive to coupling changes, so the output voltage and system power fluctuations under coupling changes are greatly reduced by the compensated dual‐frequency contributions. Based on the inductive voltage source model (IVSM), both transmission performance and cost can be significantly reduced. Therefore, in this paper, the proposed HCCT of the CPT system is constructed under 200‐kHz square wave excitation to validate the theoretical analysis and modeling. The experimental results show that the output voltage and power of the CPT system are stable at about 26 V and 65 W with maximum variations of less than 5.5% and 5.4%, respectively, in the variation range of capacitive coupling coefficients ( C M ) between 41 and 63.