Vibration of flexible rotor systems with two-degree-of-freedom PID controller of active magnetic bearings

The majority of applications of active magnetic bearings were still based on conventional PID control system. The 2 DOF (two-degree-of-freedom) PID controller can solve the problem of the optimal tuning for the disturbance response and the one for the set-point response. A 2 DOF PID control for active magnetic bearings (AMB) is discussed in this paper. According to fundamental principle of finite element mathematical model of the flexible shaft is presented. The controlled plant of 2 DOF PID mathematical model is determined. Control parameters of the 2 DOF PID systems for active magnetic bearings are discussed. The active magnetic bearing laboratory system is shown. The obtained experimental results show that 2 DOF PID controller of the active magnetic bearings-flexible rotor system is stable through the first critical speed.