Design of a contactless battery charging system

Inductive contactless energy transfer systems (CETS) transfer electric energy between their input and output section without any wired connection. The coupling device consists of two coils whose setup is a crucial issue in building up a CETS. This paper presents the design procedure of the coils of a CETS intended to charge the battery pack of electric city car. The procedure encompasses the determination of the inductive parameters of the coils when ferrite cores with different geometries are considered. Topology and sizing of the power inverter supplying the transmitter coils are also addressed. The results of the numerical analysis are validated by the outcomes of finite element method and power circuit simulation simulations.