Development of a Cross-Type Magnetic Coupler for Unmanned Aerial Vehicle IPT Charging Systems

Inductive power transfer (IPT) is an optimal way for the unmanned aerial vehicle (UAV) wireless charging. The magnetic coupler is the key component in the IPT system, which determines the power transmission capacity and efficiency in IPT system. Due to the particularity of UAV application, the magnetic field height should be strictly limited to avoid the damage caused by high frequency magnetic field heat the UAV's metal equipment. A cross-type magnetic coupler with receiving coil placed on UAV's one landing gear was proposed to solve this problem, but it has the possibility of making UAV fuselage imbalance. Therefore, a novel cross-type magnetic coupler is proposed to overcome its difficulties in this paper, and most of magnetic fields are restrained to be lower than UAV's landing gear height h1=145mm, which will not cause damage to the UAV's equipment. And a simple and practical iterative method for designing the magnetic coupler geometry parameters is proposed, with simplification of the complex design process for the finite element analysis, improves the design efficiency. The experimental results show that the system can charge the 260W UAV normally with the system efficiency of 91.577% within the misalignment range of X-axis direction 25mm, Y-axis direction 40mm and rotation 25°.