Simultaneous Wireless Power and Information Transfer Based on Phase-Shift Modulation in ICPT System

Compared to traditional simultaneous wireless power and information transfer (SWPIT) technologies, communication technology utilizing the output harmonic component of an inverter as a signal carrier can achieve high-performance signal transmission without affecting power transmission. The SWPIT technology based on phase-shift modulation in inductively coupled power transfer (ICPT) system is proposed in this article. By changing the phase angle of the inverter, a trapezoidal wave current is generated on the primary coil, and a frequency selection circuit is added on the secondary side to separate the fundamental and harmonic currents. The fundamental component current is used for wireless power transfer while the harmonic current is used to transmit the signal. Firstly, the structure and working principle of SWPIT system based on phase-shift modulation in ICPT system are analyzed. Then, a system equivalent model is established and the reactive power is analyzed in depth. Next, the phase angle variation range is determined by crosstalk analysis. Finally, the correctness and effectiveness of the proposed technology are verified with an experimental platform at 50 W. The experimental results demonstrate that the power and information can be transmitted stably with output voltage fluctuation less than 3%, and the signal transmission rate up to 6 kbps.