Inductive Power Transfer for Automotive Applications: State-of-the-Art and Future Trends

The paper discusses the development status of the inductive power transmission for automotive applications. This technology is, in fact, gaining the interest of electric vehicle manufacturers as an effective strategy to improve the market penetration of electric mobility. Starting from the origin of this technology, the paper presents an overview of the current state of the art as well as the current research and industrial projects. Particular attention is devoted to the description of a prototypal system for the dynamic inductive power transmission whose goal is to extend the battery range by a fast partial recharging during the movement of the vehicle.

I. Introduction

Electricity is a very common vector to convey energy, and its wireless transmission has been of interest of researchers for centuries. Remarkable examples are Faraday's experiments on electromagnetic induction and energy transmission through fluids in 1832 [1], the applications of the radio frequencies communications investigated by Hertz in 1895 [2], and the Tesla's experiments on the wireless electric energy transmission at long distances [3] in 1904. In the last decades, the scientific community has defined as wireless power transmission (WPT) the different ways to transfer energy at distance without wires. Today this definition covers several technologies in a wide range of applications, power, and distances. Fig. 1 schematically shows the most common technologies for WPT involving electromagnetic fields [4]. WPT technologies seem to represent an effective way to reduce the problems of costs and management of the batteries installed on electrical vehicles (EVs), eliminating the major barrier to the electro-mobility diffusion. In this paper, the authors provide a review of a particular technology in the domain of WPT called resonant inductive power transmission (IPT) for the charge of electric vehicles.