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 axial misalignment. The multiwinding solenoid transmitter coil is designed and analyzed, which can improve axial misalignment tolerance. The proposed magnetic coupler was optimized, which shows that the mutual inductance of the proposed magnetic coupler remains 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 remains nearly stable when the axial misalignment increases to 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 to 481 W when the axial misalignment increases from 0 to 80 mm.