Magnetically Coupled Resonance WPT: Review of Compensation Topologies, Resonator Structures with Misalignment, and EMI Diagnostics

Abstract

Magnetically coupled resonance wireless power transfer systems (MCR WPT) have been developed in recent years. There are several key benefits of such systems, including dispensing with power cords, being able to charge multiple devices simultaneously, and having a wide power range. Hence, WPT systems have been used to supply the power for many applications, such as electric vehicles (EVs), implantable medical devices (IMDs), consumer electronics, etc. The literature has reported numerous topologies, many structures with misalignment effects, and various standards related to WPT systems; they are usually confusing and difficult to follow. To provide a clearer picture, this paper aims to provide comprehensive classifications for the recent contributions to the current state of MCR WPT. This paper sets a benchmark in order to provide a deep comparison between different WPT systems according to different criteria: (1) compensation topologies; (2) resonator structures with misalignment effects; and, (3) electromagnetic field (EMF) diagnostics and electromagnetic field interference (EMI), including the WPT-related standards and EMI and EMF reduction methods. Finally, WPT systems are arranged according to the application type. In addition, a WPT case study is proposed, an algorithm design is given, and experiments are conducted to validate the results obtained by simulations.

Management of Multiple-Transmitter Multiple-Receiver Wireless Power Transfer Systems Using Improved Current Distribution Control Strategy

“…Under the proposed control condition based on (14), the voltage and the current distribution are analyzed as follows:…”

“…(b) The voltages U i2 at the receiver coils generally remain unchanged despite the variation of β i1 . It is because based on the constant output voltage condition the output voltage U o remains unchanged, and the β i2 has to remain unchanged based on (14) to provide high efficiency. Therefore, according to (3), the voltages U i2 at the receiver coils generally remain unchanged.…”

“…In recent years, many studies have been carried out using various approaches to increase system efficiency. Some research [14,15] has increased system efficiency by introducing new compensation networks. A mixed-resonant coupling model is developed [14,15] to either improve the transfer efficiency or extend the transfer range, which finally achieves 85% efficiency at a distance of 10 cm.…”

“…Some research [14,15] has increased system efficiency by introducing new compensation networks. A mixed-resonant coupling model is developed [14,15] to either improve the transfer efficiency or extend the transfer range, which finally achieves 85% efficiency at a distance of 10 cm. Resonators [6,16] are added for a short distance to enhance magnetic field coupling.…”

A Fractional-Order Element (FOE)-Based Approach to Wireless Power Transmission for Frequency Reduction and Output Power Quality Improvement

“…In [8], the authors propose a simple method for the analysis of the resonance frequency of a planar spiral coil to evaluate the lumped parameters of the coils. Using the technology of electromagnetic resonant couplings WPT [9], the authors addressed the fact that the output power can reach 100 W. Ref. [10] showed that magnetic resonant coupling WPT normally works in megahertz and its efficiency is improved with increasing frequency.…”