Tri-coupled Dual-LCC Compensation Network for Wireless Charging of AUVs with High Misalignment Tolerance

Inductive Power Transfer (IPT) technology has gained significant attention due to its broad range of applications, including wireless charging of Autonomous Underwater Vehicles (AUVs). During the charging process, an IPT system needs to provide stable output power, even when the AUV experiences coupling misalignments. This paper proposes a dual-LCC compensation network based on a tri-coupled coil structure for achieving a constant voltage (CV) output under misalignments and load variations. The primary side consists of three power transmission coils coupled with the secondary coil, and the mutual inductance between the coils can significantly affect the output power. By optimizing the coil parameters, the system can achieve a wide misalignment tolerance and stable CV output. A mathematical model is established, and zero voltage switching (ZVS) characteristic obtained. A 160W prototype is built to verify the effectiveness of proposed system. And the experimental results show that the system output voltage achieves both load independence and high misalignment tolerance. Under normalized axial displacement of 0.7 and radial displacement of 0.8, the output fluctuation remains below 5% at 91.14% of power efficiency.