An Underwater Wireless Power Transfer System with Improved Misalignment Tolerance

An underwater wireless power transfer (WPT) system is proposed in this article for autonomous underwater vehicles (AUVs) to mitigate the influence of the axial misalignment. The multi-winding solenoid transmitter coil is designed and analyzed, which can improve axial misalignment tolerance. The proposed magnetic coupler was optimized, which shows the mutual inductance of the proposed magnetic coupler keeps relatively stable against the large axial misalignment. An underwater WPT prototype based on the proposed magnetic coupler was set up and the theoretical and simulated analysis are verified by the experimental results. The output power maintains nearly stable when the axial misalignment increases to the 80% of the 100 mm coil width, and the output power fluctuation rate is below 6%. The system efficiency varies from 89.4% to 90.4% and the output power ranges from 454 W to 481 W when the axial misalignment increases from 0 mm to 80 mm.