Electromagnetic Bearing Rotor System Dynamics Studies

The electromagnetic bearings rotor system, as a kind of typical electromechanical equipment which integrate the mechanical dynamics, scientific testing, signal processing technology, electromagnetic theory, electronic technology and computer control science, is composed by three parts such as Machinery, Electricity and Software. The electromagnetic force must be regulated carefully to keep the rotor in the correct position. For the working environment is complex, electromagnetic bearing rotor in the course of the practical application will be some load on rotor. The magnetic rotor will off the center by all kinds of unfavorable factors. The vibration noise will be generated by the eccentric mass, and this will not only reduce of the mechanical properties and endurance, but also cause the serious accident. The dynamic characteristics of the electromagnetic bearings, experimental and theoretical study of the active magnetic rotor-bearing system are shown in this thesis. The main research works are as follows,(1) The mathematical expression of the damping and the stiffness of the active magnetic rotor-bearing has been made by the frequency domain analysis of the damping and the stiffness. The essential theoretical basis and guiding ideology has been put forward by the analysis of the circuit parameters in the active magnetic rotor-bearing system.(2) The rotor is supposed as a rigid rotor by simplifying of the active magnetic rotor-bearing system. The gravitational and eccentric action, as well as the different loading condition is considered in the rotor dynamics analysis. The analysis of the rotor dynamic behavior is done by the simulation study with MATLAB software. The stable operation of the no load active magnetic rotor-bearing system can be kept. The amplitude is increased but still in the system allowance scope when one or two mass loading. The stable operation of the system is broken when ten times immobilization is added with the rotational speed is higher than a certain rotation speed.(3) The experiment is operated on the active magnetic rotor-bearing system test-bed. The chart of axes track and time-domain diagram is made by adding on different mass loading. The research shows that the controller can keep the stable operation of the system with one or two mass loading.