调幅调谐式的双向能量与信号同步传输

Amplitude-modulation tuned bidirectional simultaneous power and signal transmission

关键词:  无线电能传输（WPT）  信号双向传输  移相全桥  电容调制  解调电路

Key words:  wireless power transfer(WPT)  bidirectional signal transmission  phase-shifted full-bridge  capacitive modulation  demodulation circuit

摘要:

为解决感应式无线电能传输中双向能量与信号同步传输系统存在的结构复杂、传输速率低、能量信号串扰等问题,提出了一种新型基于调幅调谐式的双向能信同传方法。文中通过改变逆变器移相全桥控制的移相角对正向信号进行调幅调制实现信号正向传输,采用改变副边谐振电容对反向信号进行调谐调制实现信号反向传输,从而使得线圈两端电流带有信号特征,并利用电流互感器将带有信号特征的电流信号通入解调电路中还原信号。首先,通过对电路结构进行理论推导分析；其次,采用Matlab/Simulink进行仿真分析并且验证理论分析的正确性；最后,根据仿真结果搭建了一个功率为120 W实验平台。结果表明:在功率为120 W的条件下,负载电压波动小于3%,电能传输对信号传输影响较小,可实现正向4 kbps、反向20 kbps的高速半双工传输,信号传输误码率为0.1%；仿真试验结果证明了该方法在感应式无线电能传输中能够有效实现双向能量与信号同步传输,具有较高传输速率和低误码率,可为无线电能传输系统设计提供参考。

Abstract:

To address issues such as structural complexity, low transmission rates, and power-signal crosstalk in bidirectional power and signal synchronous transmission systems for inductive wireless power transfer, a novel bidirectional power-signal synchronous transmission method based on amplitude modulation and tuning is proposed. In this paper, the forward signal is amplitude-modulated by changing the phase shift angle of the inverter phase-shifted full-bridge control to achieve forward signal transmission. The reverse signal is tuned-modulated by changing the secondary resonant capacitance to achieve reverse signal transmission. This results in the current at both ends of the coil carrying signal characteristics. A current transformer is then used to feed the current signal with signal characteristics into the demodulation circuit to restore the signal. First, theoretical analysis of the circuit structure is conducted. Then, simulations are performed using Matlab/Simulink to verify the theoretical analysis. Finally, a 120 W experimental platform is constructed based on the simulation results. Experimental results demonstrate that at a power 120 W, the load voltage fluctuation is less than 3%, and the impact of power transmission on signal transmission is minimal. The system achieves half-duplex communication with a forward rate of 4 kbps and a reverse rate of 20 kbps at a bit error rate of 0.1%. Both experimental and simulation results confirm that this method effectively achieves bidirectional power and signal synchronous transmission in inductive wireless power transfer systems, offering high transmission rates and low bit error rates, which provide valuable guidance for wireless power transfer system design.