Detuning Compensation Enables Wide‐Range Load‐Independent Output and ZVS for Domino Wireless Power Transfer Systems

Cross‐coupling among domino coils complicates the power flow paths and prevents the wireless power transfer system from achieving constant output across a wide load range. To address this issue, this article proposes a detuning compensation method that can achieve load‐independent zero‐phase‐angle (ZPA) and constant output conditions simultaneously without additional hardware. In the proposed method, only the detuning degree of the receiving circuit is adjusted to achieve the design goals. A novel characteristic that has a set of hidden ZPA frequencies exists in domino wireless power transfer system. Based on the quadratic eigenvalue problem (QEP), this characteristic is explained in detail. By adjusting the detuning coefficient of the receiving coil, the constant‐voltage (CV) frequencies can coincide with the hidden ZPA frequencies to enable the system to better achieve zero‐voltage switching (ZVS), and when the detuning coefficient is not adjusted, the constant‐current (CC) frequencies are equal to the ZPA frequencies. Finally, a four‐coil experimental prototype was constructed. The experimental results show that after detuning compensation, the system achieves CV output along with ZPA operation, and the system transmission efficiency has increased by at least 3.8% and by up to 16.51%.