Analytical PI Design by Using Closed-Loop Stability Constraints and H8 Theory for Relativity Rotary Machine

In order to suppress the torsional vibration of rotary machine, a PI controller was analytically derived based on stability of the closed-loop system and H∞ mixed sensitivity function. This novel design procedure is adapted to some unstable and critically stable systems, and a single parameter T1 is included in the controller, which can be determined by the disturbance rejection capability and robust stability, at the same time, two performances can arrive at a better compromise by tuning T1. At last, the simulation examples and experiment were provided to show the superiority of the proposed method.