Design, analysis, and application of multiple-frequency multiple-receiver wireless power transfer

Abstract

In recent years, wireless power transfer (WPT) is increasingly popular due to its cableless, better convenience and high flexibility. Usually, the WPT technique owns the advantages of electric isolation, safety, reliability, and low maintenance. Based on these advantages, the WPT technology has been maturely developed for biomedical implants, portable devices charging, and parking electric vehicle (EV) charging. Moreover, WPT is a kind of promising technique, which is changing the style of power supply in our daily life and innovatively showing great potential on some emerging applications, such as dynamic EV charging, wireless motors, wireless lighting, and wireless heating. Particularly, the multiple-receiver WPT system has been widely researched to power several ubiquitously existent devices or extend the transmission distance. Owing to the ever increasing need on smartphone charging and dynamic EV charging, the multiple-receiver WPT is becoming more attractive to charge all devices simultaneously. In order to further improve the feasibility and flexibility of multiple-receiver WPT, the multiple-frequency WPT has become an interesting research topic to targetedly deliver power to the specified receiver. The purpose of this thesis is to investigate and implement the emerging applications of the multiple-frequency multiple-receiver WPT. Firstly, the development of multiple-coil WPT system and an overview of resonant circuits with emphasis on various converters and selective multiple-frequency WPT are presented. Based on the previous research outputs, the resonant circuits for WPT are reviewed, including non-resonant converters, resonant inverters and multiple-frequency selective WPT system. Secondly, the single-transmitter multiple-frequency wireless motor drives are proposed and implemented to eliminate the converter, battery, and controller at the motor side, including multiple-receiver wireless permanent magnet DC motor drive, wireless separately excited DC motor drive, and wireless switched reluctance motor drive. Moreover, the time-division multiplexing and burst firing control method are adopted to accomplish the simultaneous and independent wireless power control to different motors or motor windings. Next, the idea to incorporate the concept of wireless motor and self-drive circuit is proposed as a wireless bidirectional servo motor drive, which shows great potential for applications in the electrocution free and totally sealed environment. Subsequently, a dynamic wireless charging system for multiple automatic guided vehicles is discussed to perform the wireless charging and automatic navigation without using guiding sensors on the ground. Furthermore, the multiple-resonator wireless lighting system for a fluorescent lamp is proposed to eliminate the bulky ballast and extend the transmission distance. Finally, all the key performances of the proposed multiple-frequency multiple-receiver WPT applications are thoroughly investigated by finite element analysis, while the experimental setups have also been established to validate the proposed ideas.