A Dual-Coupled LCC-Compensated IPT System With a Compact Magnetic Coupler

This paper proposes a dual-coupled LCC-compensated inductive power transfer system with a compact magnetic coupler to improve misalignment performance. In the magnetic coupler, the main coils form the first coupling, and compensation inductors are integrated with the main coils to form a second coupling. In the design presented in this paper, the main coils are unipolar and the compensation inductors are in a Double D structure. The fundamental harmonics approximation method is used to analyze the circuit, and the couplings between the main coils and compensation inductors are considered to determine the net power flow. In misalignment cases, it is shown that the coupling between the compensation inductors, and the cross couplings between the compensation inductors and main coils, contribute to increasing the system power. A 3.5 kW prototype is designed and implemented to validate the proposed dual-coupled system. The primary coil size is 450 mm x 450 mm, and the secondary coil size is 300 mm x 300 mm. Experimental results show that the proposed dual-coupled system can significantly improve the misalignment performance, and retains at least 56.8% and 82.6% of the well-aligned power at 150 mm misalignment in the x-and y-directions, respectively.