Study of Dynamic Robustness of Servo Control System on a Water PressKONG Xiangdong1,YAO Jing1,GAO Yingjie1,ZHANG Qin2 (1.Yanshan University,Qinhuangdao 066004,China; 2.University Illinois of Urbana-Champaign,Urbana,IL,USA)The reliability and robustness of the electro-hydraulic servo control system for heavy-duty forging machine play an important role in forging processes. A mathematic model of 50 MN water press for free forging was created in this research. The dynamic robust compensator integrating with PID control method is designed and applied to the mathematical model simulation. The simulated results approved that the dynamic robust compensator application restrains interference from extra load and improves the electro-hydraulic position servo control system accuracy and stability.electro-hydraulic servo control system; water press; free forging; robust compensator