Abstract
In this study, electromagnetic fields and mutual inductance of two interacting coils were computed analytically, and the results were compared with numerical solutions and measurements. For the analytical solution, the fields were expressed in spherical coordinates in each coil’s frame. The total field due to two coils was calculated using superposition, resulting in infinite series involving associated Legendre functions. The numerical computations were carried out by finite element analysis capabilities of ANSYS Maxwell. At the end, the self-inductances and the mutual inductance coefficients between the coils (which depend on the angle between the coils) were computed. The results (analytical, finite element method, and the measurements) were compared, obtaining good agreement for various relative positions of the coils.