Design of Magnetic Coupler for a 3 km Underwater AUV Wireless Charging System

The complex underwater environment presents significant challenges for wireless charging of Autonomous Underwater Vehicles (AUVs), while the deep-sea environment imposes new requirements on the compressive strength of the coupler. This paper divides the conventional planar coil into four smaller coils, reducing the overall pressure-bearing area while leaving space in the center of the coil for the pressure-bearing structure. By altering the coil winding direction, the diagonal currents are made to flow in the same direction, thereby connecting the magnetic circuit and increasing the power density of the coupler. Experimental tests were implemented on an experimental prototype, indicating that the output power of can reach 1800W.