Design Method of Digital Robust Speed Servo System Considering Output Saturation

Abstract

When a robust servo system having an integral element has a large error input, it often has the windup phenomena caused by output saturation. It is very difficult for a strictly proper and high order controller to avoid having the windup phenomena caused by output saturation. This paper newly proposes the digital robust speed servo system with the complete consideration algorithm of outputsaturation. The proposed algorithm completely considers the output saturation of robust speed controller connected to PI current controller in series. Moreover, this method can apply to both PI speed controller and H∞ speed controller. The experimental results show that the robust speedservo system having the proposed algorithm has a good and stable response for a large step speed command. © 1999, The Institute of Electrical Engineers of Japan. All rights reserved.