Anti-offset performance optimization of coupling coils in wireless power transfer system based on genetic algorithm

Abstract

With the popularity of electric vehicles (EVs), the application of wireless power transfer (WPT) in EVs has attracted more and more attention. The coupling coil is the key component to realize the stable transmission of electric energy, but in the process of wireless charging, the position of the primary and secondary coils may be misaligned, resulting in the change of mutual inductance and the instability of output current and power. Therefore, the study of the structure of the coupling coil is helpful to improve the transmission performance of WPT. In order to improve the anti-offset ability of the coupling coil, a DS (Double tangent semicircle) coil model based on the DD (Double D) coil is proposed in this paper, which can improve the pick-up ability and anti-offset ability of the receiver coil. Through theoretical analysis, genetic algorithm (GA) optimization, simulation analysis and experiments, it is verified that DS coil is better than DD coil in horizontal offset state and rotary offset state. At the same time, the experiments show when the rotation angle is in the range of −45° to 45° and 135° to 225°, that the current at the receiving end remains stable, and the maximum change rate is only 0.3%. This paper is of great significance to the optimal design of WPT coupling coil.