Modal And Vibration Analysis Of A Large Induction Motor Based On Finite Element Analysis

Motor is an important driving device in industrial sector which is widely used in many industries.In 2014,China's statistics estimated that industrial motor accounts for about 75% of the total electricity consumption.Studying on high efficient motors has become an important way to save electricity.Among the problems of developing motors,vibration is the major factor which affected the running stability,system reliability and equipment safety.Therefore,studying on the vibration of motors has an important engineering value.This thesis is based on finite element analysis and modal testing technology,carried out vibration analysis and experimental research on large induction motor.The result has significant guidance for improving the stability and reliability of the motor.The main work includes:(1)Using Finite Element Analysis,the nature frequencies and vibration mode shapes were calculated for stator,rotor and the whole motor.(2)Using LMS,the nature frequencies and mode shapes were extracted for stator,rotor and motor.Comparison between FEA(Finite Element Analysis)and LMS shows good correlation.It reflects that the results are acceptable.(3)Vibration test on the platform is performed.Firstly measure the vibration during run up and coast down of cold state.Then warm up the motor by double frequency method and use the same way to acquire vibration.Finally cold state test repeated.Comparison between all the tests is intending to check the stability of vibration.