This digest analyzes the magnetic characteristics of inductive power transfer (IPT) pads for interoperability in wireless charging for electric vehicles (EVs). The distinct magnetic flux patterns of IPT pads impact the variations in pad parameters, resulting in different changes in the impedance of the compensation networks. To compare the characteristics of IPT pads, parameters such as coupling coefficient and self-inductance are measured, and finite element method (FEM) modeling is used to interpret parameter variations according to the magnetic field distribution and pad components. Based on the analysis, the compensation networks are designed for each pad, and the designed networks are validated through experimental results by a wireless charging test-bed.
