Design And Implementation Of Class-E Power Amplifier For Magnetically-coupled Resonant Wireless Power Transfer System

Accompanying with the development of science technology and economy, realizing the wireless power transfer gradually become an ambition pursued by human beings. Since the publication of the new Magnetically-coupled Resonant Wireless Power Transfer (MCRWPT), it quickly became a research hotspot in colleges and universities at home and abroad. A deep study of its principle, basic circuit structure, transfer ability and characteristics has been made. While the study on the high frequency power supply which have great influence to the efficiency and performance o the MCRWPT is less and few. In most existing research the traditional power amplifier is used as a power supply, this kind of power amplifier is of low efficiency and of less pertinence to MCRWPT system. It’s of indispensability and great significance to design a high efficiency power amplifier for MCRWPT.Based on a comprehensive understanding of MCRWPT, combining with the analysis and comparison of the characteristics of various types of power amplifier, class-E power amplifier has been proposed to realize the high frequency power supply. The basic circuit theory of the design of class-E power amplifier is introduced; the performance index of the MCRWPT power amplifier is present. Then the design and simulation of class-E power amplifier circuit is completed, including the selection of switching transistor and the characteristics simulation of the transistor, the stable circuit and basic circuit parameter design, impedance matching circuit and the power supply filter circuit design. The overall performance of the circuit is simulated by ADS simulation software. To make sure that the physical class E power amplifier has perfect performance, the rational layout of the PCB class E power amplifier is proceed, and the method of moments MOM is used to extract S parameter of the PCB for the layout joint simulation. The simulation results fulfill the requirements of design index.This paper also designs the corresponding signal circuit and DC power supply circuit for class-E power amplifier, to form a complete MCRWPT class-E power amplifier system.In order to verify the correctness and feasibility of the proposed design scheme, this paper made a class-E power amplifier system prototype, and designed a radiator and shielding box. Test results show that in broadband frequency7.5MHz-9.5MHz, output power-added-efficiency (PAE) is higher than80%, the maximum PAE can reach90%; the output power is about20W and the power gain is higher than19dB. At the same time, in order to study the applicability of the designed class-E power amplifier, a series test of more load that does not match the impedance also conducted, the test shows that even under the extreme mismatching condition, the PAE can higher than60%. It can be concluded that the designed MCRWPT class E power amplifier system is of good performance. Finally, the power amplifier system is applied in a MCRWPT, the system can work normally...