Dipole-Type Integrated Compensation Coil Design for Double-Sided LCC Topology in EV Wireless Power Transfer Systems

초록

A novel dipole-type integrated compensation coil (ICC) structure is proposed for double-sided LCC topology in electric vehicle (EV) wireless charging systems to achieve high power density and high efficiency. Unlike conventional double-D (DD) loop-type ICCs, the proposed dipole-type ICC is orthogonally integrated with the main Tx and Rx coils, fundamentally eliminating unwanted magnetic cross-coupling between the compensation and main coils. This approach ensures precise fulfillment of the LCC resonant conditions, prevents circulating currents between the ICC and main coils, and optimizes the utilization of the magnetic core without reaching magnetic saturation. Compared to conventional LCC topologies with separate filter inductors, the proposed integration substantially reduces the system’s overall form factor while maintaining excellent resonant performance. A comprehensive analysis based on gyrator modeling is conducted to accurately characterize the double-sided LCC system with the integrated dipole-type ICC. The feasibility of the proposed structure is experimentally validated through an 11-kW EV WPT system compliant with the SAE J2954 WPT3 standard. Experimental results demonstrate that the unwanted cross-coupling is suppressed to less than 5% relative to the main coupling, and misalignment tolerance remains comparable to conventional designs despite the additional integrated coils. Consequently, the proposed system achieves a high dc–dc efficiency of 93.6% at 11 kW with a 150 mm air gap, confirming the effectiveness and practicality of the dipole-type ICC for next-generation EV wireless charging applications. © 2013 IEEE.

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