磁耦合谐振式无线电能传输是一种中距离无线电能传输技术,传输距离和传输效率是该技术取得突破的瓶颈。本文通过电路模型分析了传输特性,并基于E类功放设计了一套无线电能传输装置,通过对E类功放开关过程的分析,确定E类放大器在电能传输过程产生损耗的主要原因。设计了脉冲检测式频率控制电路,通过检测MOSFET输出端电压,判断系统工作状态,调节驱动信号频率,使E类功放在负载变化的情况下能迅速做出调整,大大提高了系统的工作效率和传输功率。
The wireless power transmission technology based on resonant coupling can realize middle distance power transmission without physical contact. The bottleneck of this technology is transmission distance and efficiency. Cir- cuit theory and calculation of mutual inductance between the transmitting and receiving coil are used to model and simulate the characteristic of the resonant wireless power transmission system. The system of wireless power trans- mission based on class E power amplifier is designed in this paper. The main reasons for the loss of the amplifier during power transmission have been determined through switching process analysis of the class E power amplifier. The frequency control circuit based on pulse detection is designed, and the design can determine the state of the system and adjust optimal driving frequency by detecting the output voltage of MOSFET, then the class E power am- plifier can be adjusted quickly when the load changes. This control method significantly improves the transmission efficiency and power of the system.