volume | PIER Journals

Abstract

In the wireless power transfer (WPT) system of electric vehicles, reducing the magnetic leakage and minimizing the use of magnetic shielding materials while maintaining transmission efficiency are difficult problems. To this end, a single-hole compensated passive magnetic shielding structure is proposed in this paper, with the system's magnetic leakage reduced and transmission efficiency improved through metal shielding and passive shielding. First, the magnetic shielding principles and design concepts of the magnetic core, aluminum plate, and passive shielding coils are analyzed. The single-hole compensated passive magnetic shielding structure is proposed, and then a mathematical model of the structure is derived. Second, an optimization method is proposed, using Matlab and Ansys Maxwell software to reduce the volume of metallic materials while keeping magnetic leakage within a safe range. Finally, a WPT device based on the proposed structure is constructed according to the optimized magnetic shielding and coil parameters, and the effectiveness of the structure is validated through simulation and experimentation. The results demonstrate that, when the system output power is 4 kW, leakage is reduced by 62.7% compared to the single-hole unshielded coil structure using the same materials with the proposed structure. Compared to the all-aluminum plate and all-magnetic core structure, not only is leakage reduced by 1.2%, but there is also a reduction of 40.4% in magnetic core usage and 30.1% in aluminum plate usage. Moreover, the transmission efficiency reaches 93.49%.

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Dr. Zhongqi Li

Dr. Ziyue Gan

Mr. Liquan Ren

Mr. Bin Li

Dr. Pengsheng Kong

Dr. Hui Li

Dr. Junjun Li