Research On Fuzzy Control Strategy Applied On Complex Magnetic Bearing System

To improve the dynamic characteristics of the system and make the system get across bending critical speeds stably, the magnetic damper is introduced into the magnetic bearing flexible rotor system, and the appropriate fuzzy control strategy is used to the magnetic bearings. The main contents are as follows:The fuzzy self-tuning PID controller and the fuzzy-PI controller are designed separately on the basis of the detailed analysis of the magnetic bearing flexible rotor system, and simulated by Matlab. The control software is coded in C and assembly language and implemented on the TMS320F2812 DSP card. And the dynamic characteristics of control system designed are studied by the static and dynamic suspension experiments on the five degree of freedom setup. Study proves that the control systems designed can satisfy the damands of dynamic characteristics of the system.The magnetic damper is introduced into the ordinary magnetic bearing system. The mathematical model of the magnetic bearing flexible rotor system with the magnetic damper is established. And the dynamic characteristics of the system are analyzed theoretically. The software to the magnetic damper was coded in C and assembly language and implemented on the TMS320F2812 DSP card. The influence of the active magnetic damper using different control parameters on the unbalance vibration of the system is studied by high speed rotation experiments. The dynamic characteristics of the system using different control parameters are studied and compared with the ordinary magnetic bearing system. Study shows that the active magnetic damper in place with only a few percent of damping value of the active magnetic bearing can reduce effectively the vibration amplitude of the rotor, to help the system to get across the first two bending critical speeds stably.