Investigation into the influence of coil geometry and ferrite arrangement on the inductive wireless power transfer in electric vehicles

• Experimental investigation of five coil geometries: circular, square, rectangular, hexagonal, and double-D (DD)—used in EV wireless charging systems. • Performance assessed by coupling, air gap, efficiency, and misalignment tolerance • Ferrite arrangement kept uniform to ensure fair electromagnetic performance • Coil geometry significantly impacts coupling strength and alignment tolerance • Results guide optimal pad design for efficient, low-cost EV wireless charging Electric vehicles (EVs) demand efficient and reliable charging systems, with wireless charging offering a safe and convenient alternative to plug-in methods. The performance of wireless charging pads is strongly influenced by coil geometry and ferrite usage. This study presents a comprehensive comparison of five coil shapes such as circular, square, rectangular, hexagonal, and double-D (DD) under identical design parameters for a 1 kW resonant inductive power transfer system. Experimental prototypes and finite element simulations were employed to evaluate coupling coefficient, misalignment tolerance, air-gap dependence, and power transfer efficiency. Results, highlight clear distinctions between static and dynamic operating conditions, with certain geometries demonstrating better resilience to lateral offsets, while others exhibit limitations in longitudinal alignment. Further analysis of rotational and yaw angle misalignments reinforces the role of coil geometry in determining overall system robustness. Cost evaluation confirms reduced ferrite consumption as a critical factor for scalability. Overall, the findings establish coil geometry as the dominant design parameter for optimizing efficiency, cost-effectiveness, and spatial adaptability in EV wireless charging systems.