A novel high‐accuracy self‐ and mutual‐inductance calculation approach of planar spiral square coils for wireless power transfer systems

Summary Planar spiral square coils (PSSCs) are critical components in antennas, wireless power transfer, and induction heating systems. A precise inductance determination is essential for optimizing these systems. In this study, a novel high‐accuracy self‐and‐mutual‐inductance calculation approach is proposed for PSSCs. The methodology is validated across a broad range of geometric parameters, including outer dimensions, interturn spacing, turn count, trace width, and air gaps. Verification in all tested cases is performed using Ansys Maxwell 3D, complemented by experimental validation of the prototype. The results show a strong consistency between the proposed method, finite element method simulations, and experimental measurements. A comparative analysis of existing analytical techniques demonstrates their superior accuracy. The proposed method achieves a self‐inductance error rate smaller than 0.11% and a mutual inductance calculation accuracy exceeding 99.925 % across all the tested configurations.