Optimization of LCL-S Resonant Networks for Robust Wireless Power Transmission against Positional Offsets

In conventional resonant inductor-capacitor-inductor(LCL)-compensated wireless power transfer (WPT) systems, spatial misalignment between the coupled coils leads to significant changes in the mutual inductance, resulting in severe fluctuations in transmitted power. To alleviate this issue, this paper proposes a misalignment-tolerant compensation topology design method by introducing two adjustment factors, $\varepsilon_{1}$ and $\varepsilon_{2}$, to optimize the compensation capacitors on both the primary and secondary sides. This enables the system to autonomously regulate the current on the receiving side when coil misalignment occurs, thereby reducing output power fluctuations. An experimental platform was constructed to evaluate the proposed method, and the results show that when the mutual coupling coefficient varies between 0.13 and 0.23, the output power fluctuation remains within $6 \%$, and the transmission efficiency consistently exceeds $67 \%$.