Calculation Of The Modal Of The Permanent Magnet Synchronous Motor Spindle And The Influence To The Relatively Sound Intensity Coefficient

It is well known that noise and vibration of permanent magnet synchronous motorspindle (PMSMS) are important targets used to estimate operation performance, which havealso been difficult problems. Based on the research on identification technique to noise andvibration source, the design scheme of PMSMS is optimized and the maximum noise. Thevibration source is identified when it is working and the noise level is can also becalculated.This paper presents determination of circumference and axial mode of stator of(PMSMS) by both finite element method and analytical method compared with tests. Thethesis mainly consists of modal analysis of PMSMS, analytical calculation of modal ofPMSMS, the noise calculation of the PMSMS and the inhibition of the noise of the PMSMS.In order to investigate the influence of end cover, temperature, and mean diameter onthe circumferential mode frequencies of circular cylindrical shells, the finite elementmethod(FEM) is used to do modal analysis of circular cylindrical shells in differentparameter. It is concluded that the circumferential mode frequencies of motor has littlerelationship with its temperature rise. The temperature rise causes the natural frequency ofthe stator decline slightly. It has a linearly proportion with temperature and an inverseproportion with square of the temperature approximately. The rate of the modaltransformation is little with the temperature rise of the permanent magnet synchronous motorspindle change little. The rate of change caused by temperature rise does not impact by theorder of modal. With the fixture of the end cover, the end cover has a great influence of thevibration of the stator. This paper calculate the modal of the permanent magnet synchronousmotor spindle stator both with end bell and without end bell. With the comparison of theresult, the low order of the modal rises distinctly with end bells and end bells has littleinfluence on the modal of the stator.In practical work environment, the shape of vibration of the stator does not only includecircumference model but also include axis model. The modal and noise calculation for thepermanent magnet synchronous motor spindle without the consideration of the axis modelwill impact the veracity of the result. This paper calculates the both the circumference model and the axis model, both the results take in the noise calculation,verified the practicality ofthe predict results.The influence of the relatively sound intensity coefficient with the consideration of theaxial modal on PMSMS noise is analyzed. It is also concerned into the program ofcalculating noise in. The predict results are compared with experimental datas and thepracticality is verified.