Effective optimization methods are used to guide the optimal design of coil parameters, which is significant for improving the transmission performance of the wireless power transfer (WPT) system. Traditional methods mostly rely on the exhaustive attack method and finite element analysis (FEA) to achieve the coil parameter design, which have the disadvantages of complex modeling and time-consumption. To overcome these limitations, this study proposes an optimization strategy based on the genetic algorithm (GA), which considers the actual requirements of the efficiency and power of the WPT system. First, a direct integration method is proposed to simplify the analytical solution process of the mutual inductance between the hexagonal coils. Based on the mutual inductance model, the transmission characteristics of the hexagonal coil WPT system are deeply analyzed by the control variable method. Most importantly, with the proposed optimization objective function and its constraints, the GA is used to automatically achieve multi-parameter optimization of the hexagonal coil. Finally, a 500 W WPT system experimental platform is established, and the experimental results verify the feasibility of the proposed optimization method.
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