Design and Optimization of a Magnetic Coupling Structure with High Anti-offset for Wireless Power Transfer

As the power transfer efficiency (PTE) is rapidly reduced due to the high offset between the transmitter and the receiver in the wireless power transfer (WPT) system, a Bidirectional Staggered Solenoid Structure (BSSS) with high anti-offset performance was proposed in this paper. Firstly, the factors that affect the PTE are analyzed by establishing a mathematical model of the magnetic coupling structure. Secondly, a parameter optimization method for the traditional flat solenoid coil (FSC) is proposed, which reduces the volume of the magnetic core without reducing the anti-offset ability. Then, the anti-offset performance of the optimized magnetic coupling structure is analyzed and compared with the square, the circle, and the DD (double D) coils structure by three-dimensional (3-D) finite element analysis (FEA). Finally, the anti-offset performance of the structure is verified by a S/S compensated WPT prototype. The PTE is still high when the power transfer distance (PTD) is 164 mm. When the offset distance in X and Y directions increases from 0 to 150 mm, PTE only decreases by 2.62% and 3.71%, respectively.

Automated summary

In this paper, a Bidirectional Staggered Solenoid Structure (BSSS) with high anti-offset performance is proposed for wireless power transfer (WPT) system. A parameter optimization method for the traditional flat solenoid coil (FSC) is proposed to reduce the core volume without compromising the anti-offset ability. The structure's anti-offset performance is analyzed and compared with other coil structures, and the results show that it maintains a high power transfer efficiency even at large offset distances.