Inductance calculation nearby conducting material

This paper presents the modeling of inductances nearby conducting material. A 3-D magnetic model is derived based on Fourier analysis in which the diffusion equation is incorporated. The model is applied to calculate the mutual inductance in a contactless energy transfer system between four primary coils and a single secondary coil for different positions of the secondary coil. The calculated values are compared with finite element simulations and measurements. A difference of maximum 7% is obtained among the different methods