基于分时复合的无线供电三倍频逆变器

Triple Frequency Inverter Based on Time-Sharing Composite for Wireless Power Transfer System

受开关器件工作频率的限制,传统高频方波逆变器输出电压的频率难以提高,为满足无线电能传输系统运行频率高频化的要求,该文基于传统移相全桥逆变器,提出一种输出方波频率为开关器件工作频率3倍的逆变器及其驱动策略,并分析了逆变器在无线电能传输系统等效模型下的工作模态。与其他高频逆变器相比,其输出交流方波的频率提升为原来的3倍,开关管的电流应力降低为原来的1/3,开关管发热损耗进一步降低,具有输出更高频率的潜力;同时采用软开关技术保证逆变器较高的效率,并可利用简单成熟的移相控制方案或变频控制方案对输出功率进行调节。最后搭建了用于无线供电系统的三倍频逆变器实验平台,验证了该逆变器理论分析的正确性和可行性。

Due to the limitation of the operating frequency of switching devices,the output frequency converted by conventional high-frequency inverters is difficult to increase.In order to meet the requirements of high-frequency operation of wireless power transfer(WPT)systems,an inverter and its driving strategy,whose output square wave frequency is three times the operating frequency of the switching device,are proposed based on conventional phase-shifting full-bridge inverters in this paper.The operating modes of the proposed inverter withan equivalent WPT model are also analyzed.Compared with other high-frequency inverters,the output frequency of the inverter is increased by three times,the current stress of the switches is reduced to one third of the original,and the heat loss of the switches is also decreased,and it has the potential to output higher frequency.Meanwhile,soft switching is realized to ensure the high efficiency of the inverter,and asimple and mature phase-shifting or variable-frequency control scheme can be adopted to adjust the output power.Finally,a WPT experimental prototypebased on the triple-frequency inverter is built to verify the correctness and feasibility of the theoretical analysis and design of the triple-frequency inverter.