The Research Of Control About Rotor System Utilized By Passive Electromagnetic Damper

Rotating components are widely applied in such machines as aero-engines. Industrial compressors and electromotor. It plays important role in such national economic fields as power, aviation, machine, chem., spin and so on. The vibration can seel by unbalance of the rotor system is especially strong at article speed. So it is of significance to research Rotor Dynamics.Firstly, the author of the dissertation analyzes dynamical characteristic of the single-disc and studies the relation of critical speed, and immanent frequency of the rotor bearing system, and analysis the phenomenon and character of the whirl, and simply introduce the academic knowledge about the balance of the rotor bearing. And the author introduce the Transfer Matrix Method and the Riccati Transfer Matrix Method which can be applied to analyze and calculate the critical speed of the rotor, and writes the programs of Matlab software which checks up the Riccati Transfer Matrix Method's result of calculation. Secondly, the author introduces and compares the whole control bag of tricks in the base that the doctors' studies controlled the vibration of rotor all the world. The structure of it is similar to that of the active magnetic bearing. The damper works with DC so that sensor and closed loop control are not needed. The air gap between rotor and stator is changed with rotating of rotor. As a result, the electromagnetic field intensity is changed accordingly and fluctuating current in the damper coil is created. Damping force is mostly produced because of the phase difference between fluctuating current and displacement of rotor. The formulas of fluctuating current and damping coefficient are deduced theoretically, and the calculated results are consistent with the experimental results. Finally, in the text, the electromagnetism damper is used in the system of single-disc, and analyses the swing affect and degree while the system gets across the critical rotate speed with the electromagnetism damper, and approves the electromagnetism damper's value applied in praxis.