不同频率和脉宽的方波激励下无线电能传输效果分析

摘要

Magnetic resonant wireless power transmission is a new type of technology for conducting non-radiative,mid-range power transmission using the near magnetic field based on resonant coupling phenomena.Many research findings were achieved through calculating the coupling voltage and power with the sinusoidal alternating current as the exciting source.The pulse current can also produce alternating magnetic field which induces the alternating current,and wireless power transmission excited by the pulse current has its own features.The circuit response process and the mechanism of resonant coupling excited by the pulse current are discussed,and the conclusion that the coupling process using pulse excitation is in essence also the sine wave coupling is drawn.With this transmission method,higher power can be transmitted to the load compared with sinusoidal excitation.The transfer effects of pulse waves with different pulse widths are compared by experiment and high-frequency resonant coils can be controlled by low frequency pulse signals,by which even more effective wireless power transfer can be achieved.%磁谐振式无线电能传输技术是基于磁谐振耦合现象利用近区磁场进行非辐射性、中距离输电的新技术。许多结果采用正弦交变电流作为激励，计算耦合电压和传输功率。脉冲激励也可以产生交变磁场从而感生交变电流，此方式下的无线电能传输有其自身特点。文中分析了脉冲激励下的电路响应过程及谐振耦合机理，其耦合过程本质上也是正弦波的耦合。在同一输出电压的情况下，与正弦激励相比，用脉冲方波做激励，负载可以获得较大的传输功率。最后，通过实验比较了几种脉宽和频率不同的方波激励的传输效果。实验结果表明，可以使用低频脉冲信号控制高频谐振线圈，从而实现更为有效的无线电能传输。