Review and comparison of inductive charging power electronic converter topologies for electric and plug-in hybrid electric vehicles

For the last two decades, significant improvements in charging technologies have been made. Moreover, novel applications have been proposed and tested, obtaining important and promising results. Inductive charging for electric vehicles (EV) and hybrid electric vehicles (HEV) is one of them. Because of the positive impact that this technology represents, it is important to understand the general characteristics of this novel application. This paper aims to give a general understanding of inductive charging systems for EV and HEV. The explanation of what is an inductive power transfer (IPT) transformer and how electrical power is transferred through air is presented. The review of the electrical characteristics of an IPT transformer is shown: derivation of equations and presentation of the equivalent circuit. The analysis and comparison of two different circuit topologies is also covered (series-series and parallel-parallel). Also, to validate the theoretical concepts, an IPT transformer setup with 5cm of air gap is simulated. The plots and circuit simulations where obtained in MATLAB and SIMULINK respectively.