Research On Switched Reluctance Motor For Scroll Vacuum Dry Pump And Analysis Of Torque Ripple Suppression

In industrial production,especially in the production lines of semiconductor components,electronic chips,large-scale integrated circuits,etc.,there are extremely high requirements for cleanliness.The vacuum pump is the core component of cleaning vacuum equipment.The scroll vacuum dry pump is a mechanical pump with a simple structure,which has the function of oil-free direct discharge of the medium,and has the advantages of high efficiency,stable operation process and low failure rate.Since the rotor of the drive motor for the dry scroll vacuum pump operates in a state of high vacuum,it is difficult for the rotor to dissipate heat.The rotor of SRM is made of superimposed and stamped silicon steel sheets.There is no permanent magnet and no excitation winding,so there is no loss associated with it.In addition,the rotor iron loss of the switched reluctance motor is low,and the heat generated by this is relatively low.There is very little to say,so the internal cavity parts of the SRM have a fast cooling rate,which is very suitable as a drive motor for a scroll vacuum dry pump.Firstly,the basic structure,working principle and characteristics of the vortex vacuum dry pump and the switched reluctance motor are introduced,and the operating characteristics of the switched reluctance motor are analyzed by using the basic equations and linear models of the switched reluctance motor.Secondly,according to the working index of the vortex vacuum dry pump,the electromagnetic design of the switched reluctance motor is carried out,and a 1.5k W three-phase 12/8-pole switched reluctance motor is designed,and the ANSYS Maxwell software is used for modeling and operation characteristics analysis.,and then simulated and analyzed the temperature fields of the switched reluctance motor and the asynchronous motor used in the scroll vacuum dry pump respectively,and proved the advantages of the switched reluctance motor used in the scroll vacuum dry pump in reducing the rotor temperature.Finally,based on the initial switched reluctance motor model,three schemes are selected to compare and analyze the influence of the torque ripple of the switched reluctance motor.1.Use the rotor slanted pole method.2.The magnetic slot wedge is added between the stator slots.3.The method of comprehensive analysis is carried out by changing parameters such as stator and rotor pole arc coefficients.After simulation analysis,a scheme of chamfering the rotor teeth,opening rectangular slots on both sides of the rotor teeth,and non-uniform air gaps between the stator and rotor is adopted to further reduce the torque ripple.The effects of genetic algorithm optimization,chamfering span,slot width,slot depth,tooth tip height and stator tooth pole eccentric distance on the torque ripple of switched reluctance motor are studied.The optimal design scheme of the numerical example motor is obtained through finite element simulation,and the switched reluctance motor using the combination of rotor tooth chamfering and rectangular slots on both sides and non-uniform air gap between stator and rotor is compared with the switched reluctance motor after multi-parameter optimization.For the motor,when the average torque is basically unchanged,the torque ripple coefficient is further reduced.