Influence of Coil Characteristics on Inductively Coupled Wireless Power Transfer Systems Efficiency

Abstract

The development of electric vehicles (EVs) is crucial to the sustainable development of global transportation. Wireless Power Transfer (WPT) technology is one effective means to improve the charging efficiency of electric vehicle. At the same time, the obstacles of the traditional wired system have been alleviated. Among them, the Inductive Power Transfer (IPT) system is a better choice in electric vehicle charging applications because of its anti-offset capability and high efficiency in transmission. The paper consists of the theoretical basis, optimization technology, and implementation strategy of IPT. In the technical principle part, a multi-physics coupling model is used to analyze the quantitative relationship between transmission efficiency and coil parameters in conjunction with Kirchhoff's law. In the structural optimization part, two coil optimization schemes, circular and square, are compared. By improving the magnetic permeability and optimizing the other parameters, the key parameters were improved by 50% and 25% respectively. Finally, this paper summarized the potential research directions of WPT and how it influences the advancement of EVs. This review is aimed at researchers and industry practitioners who are committed to innovate WPT in EVs industry, intending to provide valuable insights for them.