Design and Implementation of a Uniform Power and Stable Efficiency Wireless Charging System for Autonomous Underwater Vehicles

Design and fabrication of a practical wireless charging system, which includes a submerged docking station and an autonomous underwater vehicle (AUV) with power pick-up capability, is proposed to recharge an AUV safely and autonomously. First, a docking design, based on a funnel-type docking station, an acoustic and optical combination guiding method and a position locking mechanism, is presented to smoothly dock the AUV and eliminate the dynamic disturbance during the charging process. Then, a novel magnetic structure with an overlapped direct-quadrature transmitter and a dipole receiver is proposed. The two-layer transmitting windings, decoupling each other, form a constant amplitude traveling wave under the space-time coordination mechanism for suppressing output fluctuation with misalignments. Moreover, a practical wireless charging circuit, based on current doubler, is developed, modeled and analyzed. Finally, an experimental prototype is constructed to verify the proposal. The system can deliver 1.2 kW to the load with a system efficiency of 90%, and especially the proposal achieves stable output in the range of rotational misalignment of [-30°, 30°] and axial misalignment of [-30 mm, 30 mm].