Design and implementation of a transmission system for high-performance contactless electric vehicle charging

Due to the rising electrification rate and increasing battery capacities there is a need for higher charging performance of wireless power transfer (WPT) systems in electric vehicles to keep pace with technological progress and tethered charging. The coil system has to be designed with adequate coupling and a high displacement rate as well because autonomous positioning systems are still in development. This paper shows a systems engineering design process based on pre-defined technical parameters. The significance and the quantitative consideration of an adequate displacement rate are particularly taken into account. On a methodical, efficient and practical layout, boundary conditions are defined and implemented. Design criteria for optimizing coils, litz wire, ferrites and compensation units are defined. Finally, the concept is validated and the results are shown based on an experimental setup.