Magnetic Integration of Circular Pads and LCC-LCC for EV Wireless Charging Tolerant to Misalignment

Abstract

A key component of the magnetic resonant chargers is the coupler, which must be connected to the compensation networks to improve the power transfer. The design of both structures are tightly related since the configuration of one affects the other. Thus, the integration of both structures is convenient to ease the development of other systems of the wireless charger such as the power converters and control. This integration can be optimized if physical aspects are considered. In this paper, we propose a novel physical integration of circular pads and a LCC-LCC compensation. If both systems are connected without any specific consideration, the inclusion of the reactive components in this high-order compensation network derives in a more bulky-structure. Our proposal consists in implementing the inductors of the compensation networks in the same structure of the power coils, leading to a compact system. The position of the compensation coils must be carefully analysed in order to minimise undesired coupling effects. In the proposed integration approach, we have analysed the coupling coefficients between the magnetic components for several positions to identify the optimised configuration. The feasibility of this compact structure has been validated in a prototype, proving that the power transfer levels are suitable. These tests have been carried out for different misalignment conditions, which could model its performance for dynamic charging.

Keywords

• LCC-LCC compensation
• circular coils
• magnetic integration
• wireless power transfer
• finite elements analysis
• electric vehicle