Modular Coupler With Integrated Planar Transformer for Wireless EV Charging
Vahid Zahiri Barsari, Duleepa J. Thrimawithana, Seho Kim, Grant A. Covic
Abstract
A dynamic inductive power transfer (IPT) system is a safe and convenient solution for providing power to electric vehicles (EVs) while they are driving along a roadway. This technology can help reduce the size and cost of the bulky EV batteries without limiting the EV's travelling range. In recent years, practical aspects of dynamic IPT systems have been investigated to advance various IPT technologies from laboratories into roadways. This paper suggest an IPT roadway layout, focusing on a modular IPT system configuration with an integrated semi-loosely coupled planar transformer inside the in-road coupler to mitigate the installation and maintenance concerns of IPT roadways. The proposed configuration keeps the current in the couplers constant and load-independent while providing galvanic isolation between the coupler and the converter, and can be used as a replacement for the conventional LCL and transformer configuration. In order to reduce the number of components used in each module, each in-road coupler is connected to a common H-bridge through a single DC switch to enable individual couplers to be energized independently. Mathematical analysis and simulation results are provided, and validated using a scaled 7.7 kW prototype IPT system employing the proposed configuration.