无线电能传输系统驱动源负载网络分析

摘要

To improve the transmission efficiency of resonant wireless power transfer system in high frequency condition, the class E power amplifier is used as a driving source based on the traditional structure of wireless power transfer system. An adjustment method of load network for class E power amplifier in wireless power transmission system is proposed to further reduce the system losses, and then, the optimal matching parameters of load network in soft switching condition are calculated. The effect of load network changes on the system efficiency and the state of soft switching by adjusting the duty cycle of the switch are verified. Result shows that the system output power can get 78 W at 1 MHz frequency, and the system power efficiency is up to 76�5%.%为了提高无线电能传输高频时的高效传输能力，结合谐振式无线电能传输系统基本结构，采用单管E类功率放大器作为系统驱动源，对驱动源的负载阻抗特性及影响负载网络的因素进行了分析；提出了针对无线传能系统的E类功率放大器负载网络参数调节方法；在软开关条件下计算了负载网络最佳匹配参数；通过调整开关管占空比的方式验证负载网络变化对软开关状态及系统效率的影响.结果表明，通过驱动源样机的制作以及负载网络参数调整测试，实现了在1 MHz频率下78 W功率的输出，系统效率达到76.5%.