Finite Element Analysis And Rotor Vibration Compensation On Bearingless Permanent Magnet Slice Motors

The principle of the bearingless permanent magnet slice motor is that the motor utilizes the bearingless technology to implement the radial active suspension of the 2 freedom degrees and realizes the passive suspension of the 3 freedom degrees of the axial position and tilting of the slice rotor at the same time. Besides having all advantages of general magnetic bearings, as a high-integration bearingless motor, it also has the features as follows: short shaft length, simplified structure, lower cost .etc, so it has attracted the attention of industry field and is actively developed and researched. Especially, the motor has a wide range of application prospect in special liquid drive field and ultra-pure driving field.At the support of High Technology Research of Jiangsu Province (BG2005027), and SRF for ROCS, SEM, the dissertation researches the bearingless permanent magnet slice motor configuration optimization and the unbalance vibration of magnet slice rotor. The detail contents are as follows:Firstly, based on the introduction of the basic principle of the bearingless permanent magnet slice motor, mathematics models of motor are deduced, and control system is given.Secondly, based on the introduced principle of Finite Element, magnetic fields are analyzed to validate the principle of generating radial suspension force by using the finite element ANSYS software. The relationship between the radial suspension forces and permanent magnet radial thickness is researched and the relationship between the radial suspension forces and air gap is researched under the fixed permanent magnet radial thickness. The research results can provide reference when designing and optimizing for the bearingless permanent magnet slice motor.Thirdly, the vibration due to the unbalanced weight of the bearingless permanent magnet slice motor rotor is analyzed. Through the analysis of advantages and drawbacks of current notch filter and generalized notch filter, based on control system decoupling for the bearingless permanent magnet slice motor, generalized notch filter compensatory solution is simulated and researched using force minimum criterion on Matlab/Simulink software. The simulation results prove compensatory solution validity to certain extent.Finally, digital Signal Processor TMS320F2407A and simulation environment Code Composer Studio (CCS) are introduced. Then current waveform and displacement waveform under the condition of bearing winding and driving winding electrifying respectively are obtained through experiments. The research results provide dependable experiment demonstration for steady running of the bearingless permanent magnet slice motor.