频率跟踪式谐振耦合电能无线传输系统研究

Study on Frequency-tracking Wireless Power Transfer System by Resonant Coupling

谐振耦合电能无线传输实际应用的瓶颈是谐振频率的失谐。本文基于谐振耦合电能无线传输机理和模型,分析了发射线圈与接收线圈的固有谐振频率变化对无线传输效率的影响和失谐机理,发现发射线圈电感变化是影响电能无线传输效率的主要因素之一,由此提出了发射功率源工作频率同步跟踪发射电路固有谐振频率的频率跟踪控制方法,从而保证了谐振耦合电能无线传输的谐振输电方式,避免了谐振频率的失谐,大幅度地提高了输电效率。文中制作了一个谐振频率为1 MHz的无线电能传输系统原理样机,验证了该方法的有效性。

Detuning is the application barrier of resonant coupling wireless power transfer. This paper analyzes effects about inductance variations of launch coil and receiving coil to wireless transmission efficiency based on its transmission mechanism and model, and also analyzes its detuning mechanism. Thus, it reveals that inductance of launch coil changing is one of the main influencing factors of transmission efficiency. In order to make sure that wireless power transfer by resonant coupling operates without detuning, a new method of frequency tracking control is came up with, which is, making frequency of transmitting power source tracking with the nature frequency of launch resonant circuit automaticllly. Hence, it avoids detuning and improves transmission efficiency greatly. Finally, a prototype of 1MHz wireless power transfer system by resonant coupling was made. Experimental results prove this method very well.