Impact of the wire tightness degree on circular pad with different coil size in IPT system

This paper intends to evaluate the impact of the wire tightness degree on circular pad with different Archimedean spiral coil size in Inductive Power Transfer (IPT) system. The effect mainly focuses on the sensibility of coupling coefficient to misalignment and gap variation with constant self-inductance when the dimension of the secondary coil is fixed. In this paper, the larger outer diameter of primary coil with constant inner diameter, which means a looser spiral coil, the less sensitive coupling coefficient tends to be. Besides, the larger inner diameter of primary coil with fixed outer diameter, that is, a tighter spiral coil, tends to have a less sensitive coupling coefficient. The models are built and simulated by Finite Element Analysis (FEA) tool, and the experimental data are proved to have a good agreement with simulation results.