The Design and Optimization of Ground-Side Coils for Dynamic Wireless Power Transfer Considering Coupling Variations

Abstract

Dynamic wireless power transfer (DWPT) has attracted widespread attention for its charging flexibility; short-segmented DWPT systems are more suitable for EV charging scenarios because of their higher charging efficiency and lower electromagnetic radiation, compared to long-track DWPT systems. For short-segmented DWPT systems, the structural design of the ground-side coil affects the coupling characteristics of the system, while simultaneously the electric vehicle driving speed and coil arrangement also cause coupling variations, and this will inevitably have an impact on the system’s performance. Therefore, this paper demonstrates the coupler design of a short-segmented system for electric vehicles, focusing on the optimization of ground-side coil. The coupling variations causing by driving speed of EV and coil arrangement are taken into account. Considering the tradeoffs and restrictions, a multi-objective optimization process of coils in DWPT systems is proposed based on the Pareto optimizing method, with three objectives: transfer power, high efficiency and low cost. A reasonable optimal solution is selected from the Pareto front to verify the optimizing method through a constructed prototype.