Communication-Free Robust Wireless Power Transfer with Constant Output Power and Stable Frequency

TL;DR

This paper introduces a wireless power transfer system that maintains constant power and stable frequency without complex control or communication, adapting to load changes through a pseudo-Hermitian design and simple PI control.

Contribution

It presents a novel third-order pseudo-Hermitian WPT system that achieves load-adaptive, communication-free power stability with theoretical analysis and experimental validation.

Findings

Achieves constant power transmission under load variations

Maintains stable frequency without circuit frequency changes

Eliminates the need for wireless communication for feedback

Abstract

A primary challenge in wireless power transfer (WPT) systems is to achieve efficient and stable power transmission without complex control strategies when load conditions change dynamically. Addressing this issue, we propose a third-order pseudo-Hermitian WPT system whose output characteristics exhibit a stable frequency and constant power. The frequency selection mechanism and energy efficiency of the nonlinear WPT system based on pseudo-Hermitian under the coupling mode theory approximation are analyzed. Theoretical analysis indicates that under certain coupling coefficients and load conditions, the proposed system can achieve frequency adaptation in a stable frequency mode without the need to change the circuit frequency. When the load changes dynamically, the stability of the power output is maintained using a proportional integral (PI) control strategy that only collects the voltage and current at the transmitting end, eliminating the need for wireless communication circuits with feedback from the receiving side. Experimental results demonstrate that the proposed design scheme can achieve constant power transmission when load conditions change, maintaining stable and relatively high transmission efficiency. The proposed scheme exhibits benefits in practical applications since no communication is required.