A Structure Optimized Method Based on AFSA for Soft Magnetic Strips of Inner Double-Layer Shield for Wireless Power Transmission of EV

A structure optimized method based on the artificial fish swarm algorithm (AFSA) for the soft magnetic strips of the inner double-layer shield is proposed in this paper and applied to the coupler of the wireless power transfer (WPT) system of an electrical vehicle (EV). Some structure parameters including length, height, width and distances of the strips are selected to fit their relationships with the coupling coefficient, which directly effects the transfer efficiency of the coupler by the linear fitting method. Based on these relationships, a group of parameters is obtained by the AFSA with the largest coupling coefficient and suitable volume to achieve optimal transfer efficiency without lots of repetitive results of the finite element analysis. The effectiveness of the proposed method is demonstrated quantitatively according to the outcomes and comparisons among different structure parameters and algorithms.