Modeling of mutual inductance for planar inductors used in inductive link applications

Prediction of mutual coupling is needed to characterize any inductive link system used in wireless power transfer applications. This paper presents a compact model of mutual inductance between two planar inductors at various separation distances. The proposed model is derived by solving the Neumann's integral using series expansion technique. Numerical and experimental verification have been carried out to assert the accuracy of the model. The measured and predicted mutual inductances show excellent agreement with error less than 5%.