Modeling and Stability Enhancement Method of Wireless Motor System Based on Damping Reconstruction Control

The wireless motor system eliminates the electrical connection between the power supply and the motor, ensuring high reliability and low maintenance. However, the resonance between the secondary side inductor and the dc-link capacitor, interacting with the motor drive with negative impedance characteristics, causes oscillation and instability in the dc-link voltage. This phenomenon manifests as the control-to-output function having right-half-plane poles. This article establishes an equivalent model of the wireless motor system using the short-time Fourier transform and analyzes the main factors affecting system stability. Additionally, a control strategy for implementing damping reconstruction control on the secondary side is proposed, aiming to improve system stability by equivalently increasing the secondary side coil internal resistance, thereby efficiently decreasing the system's reliance on dc-link capacitor value. Simulation and experimental results validate the effectiveness of the proposed damping reconstruction control method. This article is accompanied by a video file demonstrating the experimental operations under different operating conditions.