High Robustness Control for Robotic Wireless Power Transfer Systems with Multiple Uncertain Parameters Using a Virtual Buck Converter

• Published in: Energies (Basel) Vol. 10; no. 4; p. 517
• Main Authors: Li, Yanling, Duan, Qichang, Zou, Yang
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 11.04.2017
• Subjects: Control algorithms; Controllers; Design techniques; Magnetic fields; Methods; Optimization techniques; Power supply; Robotics; Robots; Robust control
• ISSN: 1996-1073; 1996-1073
• DOI: 10.3390/en10040517

Aiming at achieving high robustness performance in Wireless Power Transfer (WPT) systems for moving robot power supply, this paper proposes a H∞ robust control method with multiple parameters that vary randomly, including the mutual inductance, load parameter, and operating frequency. These uncertain parameters make the system control extremely difficult. A composite Upper Linear Fractional Transformation (LFT) method is proposed to deal with the system uncertainty, particularly for the mutual inductance detachment, which is very unique and important for WPT systems. A suboptimal H∞ controller design method is proposed based on Generalized State Space Averaging (GSSA) model in order to simplify the system structure. In controller implementation, a virtual buck converter for phase shifted regulation is proposed to replace real input buck converter. The proposed H∞ control method is easy to implement because only the output voltage of the WPT system needs to be sampled, and based on which a simple DSP control algorithm is developed. Simulation and experimental results have demonstrated that the proposed control method can achieve less than 15 ms response speed with 70% mutual inductance variation and 50% load variation tolerance respectively.