FEA assisted design and optimization for a highly efficient 22 kW inductive charging system for electric vehicles with large air gap and output voltage variation

The design method and optimization of a 22 kW inductive charging system (ICS) for a ground clearance range of 100 mm to 250 mm, a lateral misalignment of ±75 mm in driving direction and ±150 mm transverse to it, is described. The influence on the inductance values as well as the coupling coefficient of the coupler geometry is analyzed using state of the art finite element analysis (FEA) simulation. Additionally, mathematical analysis shows the behavior of the system for different misalignment situations and component tolerances. A fully functional prototype verifies the behavior of the FEA simulation results, the mathematical models and the electrical simulations and demonstrates a DC to DC efficiency of up to 95%.