Modeling of inductive power transfer systems - a tutorial review

Wireless power transfer systems, particularly those based on inductive coupling, provide an increasingly attractive way to deliver power without any physical connection or cables. There exists now a large literature about the topic, but generally each paper focuses on a single application and/or a typical design procedure or modeling technique. Since the covered published works belong to a variety of approaches, it can be a difficult task to understand the underlying physical aspects and modeling approaches, particularly for a newcomer to the field. This tutorial paper reviews and describes basic aspects required to model an inductive power transfer system, with a focus on practicality. The article is based on the author's work over a period of 10 yr. It introduces and explains the published methods and principles relevant to all aspects of an inductive link, such that no specific prior knowledge about wireless power transfer is required. The objectives can be divided into three main contributions: 1) To provide fundamental equations and basic principles of inductive power transfer, which are required to begin a design process; 2) To present these typical applications related to three levels of transferred power: electric vehicle (high power); drone (mid power) and biomedical implant (low power) to describe a large overview of practical systems; 3) To give newcomers to the topic an introduction to the modeling process and key aspects to facilitate any design process.