Torque Ripple Analysis And Vibration Research Of Switched Reluctance Motor For Crane

In recent years,with the rapid progress of society and the rapid development of science and technology,the design and development of high-efficiency and energy-saving crane has become one of the important research topics in the field of lifting metallurgy.The rotor cast aluminum type and rotor wind type induction motor as traditional hoisting metallurgical motor,because a series of shortcomings in the starting progress,for example,the small starting torque,the large starting current,the low efficiency of motor in low speed operation,and can't suit the high temperature and high pressure surroundings.It has been unable to meet the needs of industrial production.As a new generation of special motor,switched reluctance motor is depend on its high reliability,wide range of adjust speed,small starting current,large starting torque and high operation efficiency in the low speed operation stage,was gradually valued in the field of lifting metallurgy.Develop the research of switched reluctance motor for lifting and reusing.It has engineering practice value in the field of lifting metallurgy.In this thesis,the research object is a three phase 12/8 pole 5.5KW switched reluctance motor's prototype.Establish a mathematical model and two-dimensional finite element simulation model.Based on the time-step finite element method,the operation characteristic curves of switch reluctance motor speed corresponding to motor output torque,obtain the motor operation efficiency and motor output power.calculate the current flux characteristic curves of different rotor position angle.The influence of pole arc coefficient of stator and rotor,analyse the winding turns and air gap length on motor torque ripple,and switched reluctance motor is built.The voltage and current waveforms of the prototype under no-load stable operation are collected on the experimental platform.By comparing the experimental results and the simulation results,verified the accuracy of the calculation method.Research and analysis the distribution characteristics of electromagnetic force density of the stator teeth of switched reluctance motor.Establish the simulation model of two dimensional switched reluctance motor.Analyzes and calculate the distribution characteristics of the magnetic density in the air gap magnetic field of the switched reluctance motor according to the characteristics of the serious electromagnetic vibration of the switched reluctance motor,decomposes the radial air gap magnetic density harmonic,and obtains the fundamental wave and each harmonic component.The distribution characteristics of the magnetic density on the surface of the stator tooth top are calculated and analyzed.The spatial and temporal distribution of the radial electromagnetic force acting on the inner surface of the stator is studied.The frequency spectrum of the radial electromagnetic force density is analyzed,and obtains the change rule of the amplitude of the radial electromagnetic force density in the frequency domain.Depend on the classical mechanics theory,establish the three-dimensional finite element calculation model of the prototype.Based on the obtained finite element calculation results,the coupling calculation of the transient electromagnetic field and the transient structure field is realized in the transient dynamics analysis module.The electromagnetic force density acting on the stator surface of the motor is used as the excitation source,and is coupled to the three-dimensional model of the prototype for the transient dynamics analysis.The motor X,Y.The vibration displacement response in Z direction and the vibration speed response in X and Y direction.Taking the stator part of the motor as the research object,the harmonic response of the stator is analyzed,and obtains the vibration displacement and vibration speed response of the stator in the X and Y directions in the frequency domain.