Wide Rotation-Misalignment-Tolerance Design of Magnetic Coupled Structure for AUVs Wireless Charging System

Wireless power transfer (WPT) technology facilitates convenient and flexible power replenishment for autonomous underwater vehicles (AUVs). However, the rotation misalignments often happen between the transmitter and receiver sides, which would cause significant fluctuations of system's output power and efficiency. To tackle this problem, this article introduces a novel magnetic coupled structure (MCS) with a U-shaped bipolar coil transmitter and an arc-shaped unipolar receiver, owing the merits of complementary field enhancement properties to achieve a wide-range of rotation misalignment tolerance (RMT). Moreover, the adjacent transmitter and receiver coils are specially designed with opposite magnetic fields, thereby achieving field enhancement and maintaining stable mutual inductance over a wide-range of rotation angle. An experimental prototype with 600 W/85 kHz is built to verify the effectiveness of the proposed RMT-MCS. Experimental results demonstrate that our proposed MCS has a wide-range of RMT ability. The measured output power can maintain stable around 500 W and the system efficiency are all over 88% within a rotation angle of 240°. Meanwhile, the maximum fluctuations of output power and efficiency are 4.35% and 2.34%, respectively, as the load varies from 10 to 50 Ω.