Analysis And Research On Rotor Loss And Structural Strength Of High-speed Permanent Magnet Synchronous Motor

High speed permanent magnet synchronous motor has been widely investigated in the field of electrical engineering since it has small volume,high power density and high efficiency.The speed of high-speed permanent magnet synchronous motor is high,and the rotor wind friction loss and rotor eddy current loss are much higher than those of ordinary one.Due to the small size and difficulty of heatb irreversible demagnetized.Due to its high speed,it is difficult to meet the requirements of rotor strength.In view of the above problems,the eddy current loss,wind friction loss,temperature field and rotor dynamics of a 100 k W,50000r/min high-speed permanent magnet motor are simulated and analyzed.Firstly,the rotor eddy current loss of high-speed permanent magnet synch-ronous motor is calculated by analytical method and finite element.Then compare the two results.The variation of current density between sleeve and pe-rmanent magnet under different thickness of sleeve and its causes are analyze-d.The eddy current losses of sheath and permanent magnet under different thickness sheath are calculated,and the changes and causes of eddy current los-ses are analyzed.Then,the air friction loss at different speeds is calculated by analytical method and finite element method respectively.The magnitude of air friction loss at different speeds is calculated,and the variation of air friction loss is analyzed.By calculating the air friction loss in casing with different roughness,analyze the law of air friction loss,calculate the air friction loss in casing with different roughness,analyze the law of air friction loss,and calculate the size of air friction loss under the length of air gap.The regularity of air friction loss is analyzed.For the high-speed permanent magnet motor under different cooling modes,the temperature is simulated.The best cooling mode is determined.The influence of wind speed on the temperature rise of fast magnetic motor parts is analyzed.Finally,the stress analysis of casing and permanent magnet is carried out,which is verified by finite element method.The stress changes of PM and sleeve under different operating condition are analyzed.The different rotational speeds,different disturbances and voltage changes of permanent magnet and shell at different temperatures are analyzed.the Campbell diagram of the rotor system is drawn,and the first three critical speeds of the rotor system are calculated.