Abstract：Wireless power transfer (WPT) technology, which uses non-physical contact to transmit electric energy, effectively solves the problems of water leakage and electric leakage in the traditional underwater power transmission process, and has a good application prospect in underwater electrical equipment. Therefore, this paper designs a cage-like docking device with rotary loosely coupled transformer (LCT) to realize underwater wireless power transmission, which can effectively avoid the radial offset of automatic underwater vehicles (AUV). In view of the significant influence of mutual inductance on the performance of radio power transmission, this paper focuses on solving the mutual inductance of LCT, and establishes the mutual inductance calculation model of the structure by using Biot-Savart Law. On this basis, the influence of axial offset on rotary LCT is analyzed from multi-dimensional parameters such as mutual inductance, coupling coefficient, output power, efficiency and secondary side length. The simulation results show that the anti-axial offset ability of rotary LCT is strong. Finally, a set of LCL_S type compensation structure wireless power transfer device is designed and developed. The experimental results verify the correctness of the theory and simulation analysis, which has a certain engineering application value.
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2021, Vol. 36 
