Characteristics Analysis And Structure Optimization Of The Centrifugal Compressor Electromagnetic Controller

Centrifugal compressors are indispensable rotating equipment in modern industrial machinery.There are considerable economic losses in industrial production due to frequent unpredictable unit faults.Research finds that the majority of failures are due to rotor instability.The study finds that the vast majority of failures are due to rotor instability.In order to avoid this kind of the failure,the rotor can be monitored synchronously,and the instability can be detected and adjusted in time.The electromagnetic controller can control the currents to realize the controllability of the magnitude and direction of the bearing.The use of electromagnetic controllers can effectively reduce the incidence of forced parking.This paper studies the electromagnetic controller and applies it to the monitoring and controlling process.The main contents of this paper are as follows:(1)In order to meet the requirements of bearing load during the test,the rotor is loaded by an electromagnetic bearing in bearing test rig.A large-volume radial electromagnetic controller is designed which can provide a bearing capacity exceeding 10000 N.The stator yoke thickness and the secondary pole width of the structure are optimized so as to ensure a smaller structural volume.At the same time,the coupled analysis of magnetic-temperature field is also performed on the optimized structure,and the distribution of the temperature field during the simulation is obtained.The data is compared with the experimental data.Compare the simulation results with the experimental data.The results are basically the same.(2)In order to perform self-healing analysis on the axial displacement of the centrifugal compressor,a axial electromagnetic controller that can be applied to the axial control is designed.The stator pole width,clearances and current conditions of the structure are optimized and analyzed.A axial electromagnetic controller is designed to take over the role of the subsidiary thrust bearing.The device can feedback the temperature of the bearing pad to the axial electromagnetic controller by means of temperature sensor.According to the temperature result,coil current and electromagnetic force can be adjusted,which achieve the purpose of adjusting the temperature of the bearing pad and the axial displacement.(3)The permanent magnet bias controller has been designed and simulated.A bias magnetic field can be created due to the permanent magnet bias structure,and the electromagnetic structure can adjust the current to change the magnetic flux density in the gap between the rotor and the stator,which can achieve the effect of ensuring the balance of the rotor.The advantages of this structure comparing to the electromagnetic structure is that the structure volume can be reduced to some extent,and the number of power amplifiers can be reduced,thereby reducing costs.(4)Monitoring and warning of destabilized flutter in the rotor blades of engines or fans is the main method to prevent chattering-induced accidents.A simulation experiment device is developed,which can inspect flutter instability fluttering phenomena based on electromagnetic force.ANSYS is used to optimize the structure with the maximum electromagnetic force target,and Maxwell analysis can study the process of changing the excitation force of the blade after passing through the magnetic field of a single set of magnetic poles.Based on this,the modal harmonic response analysis of the blade was simulated.Finally,a preliminary experiment is conducted on the test rig which can prove that the test rig is sufficient for vibration test analysis.