FDTD Modeling of Coils for Wireless Charging Applications
Keywords:
Coils, FDTD, flux coupling, magnetized ferrite, simulation and wireless chargingAbstract
Wireless power transfer using inductive/ resonant coupling is studied using the finite-difference time-domain (FDTD) method. Three-dimensional FDTD models are used to simulate the source and load loops as well as frequency-dependent magnetized ferrite shields. A series of tests are run to determine the required distance between the coils and the domain edges, the PML thickness, and convergence level. The FDTDcalculated coil parameters (self-inductance and quality factor) are then validated against measurement results. The efficiency of the inductive link is studied without ferrite shields and then with two ferrite slabs added. It is observed that adding ferrite slabs improves the efficiency by ~40%.
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