Experimental Investigation on Vibration Control of Rotor-bearing System with Active Magnetic Exciter

Vibration control is an efficient way to minimize a rotating machine's vibration level so that its vibration fault-free can be realized. While, several factors, such as unbalance, misalignment and instability, contribute to the serious vibration of rotating machines. It is necessary that one apparatus can depress vibration caused by two or more reasons. The fault self-recovery(FSR) mechanism is introduced and investigated. Strategies of vibration control are investigated theoretically using numerical method firstly. Active magneticeleetric exciter(AME) are selected as the actuator of a FSR device because it can provide suitable force by varying the control current in the exciters depending upon a proportional and derivative control law. By numerical study, it is indicate that only a small control force is needed to improve stability margins of the compressor and prevent subsynchronous vibration fault efficiently. About synchronous vibration, three control strategies, searching in whole circle, fast optimizing control (FOC), and none mistaking control, are investigated to show which of the control strategy can realize the fault self-recovery in the shortest time. Experimental study is conducted on a test rig with variable rotating speed. Results of the test indicate that the non-mistake control strategy can minimize synchronous vibration in less than three seconds. The proposed research can provide a new insight for subsynchronous and synchronous vibration restraining about centrifugal compressor.