高速永磁电动机气体轴承-转子系统振动特性

结合45kW高速永磁同步电动机试验装置及系统,研究了轴承供气压力和升速率对轴系稳定性的影响.针对升速过程中的分岔图、频谱图以及轴心轨迹等特征进行分析,发现高速永磁电动机中存在低频振动的特性.试验结果表明:通过调整轴承供气压力,转子升速的分岔点由18400r/min推迟到38900r/min,并消除了38900r/min以下的半速涡动;改变升速率(升速率由825(r/min)/s变为660(r/min)/s),转子通过临界时工频幅值从95μm降低到75μm. 

Vibration characteristics of gas bearing-rotor system of high-speed permanent magnet machine

In the 45kW high-speed permanent magnet machine test rig,permanent magnet machine's raising speed experiment was made to research the influence of bearings supply pressure and the raising speed rate on the shaft stability.Bifurcation plot,frequency-domain characteristic and axes locus were analyzed to find sub-synchronous vibration.The result shows that:adjusting the bearing supply pressure can control bifurcation point from 18400r/min to 38900r/min, and eliminate half-speed whirling under 38900r/min.To change the raising speed rate (from 825(r/min ) /s to 660(r/min ) /s) can reduce power frequency vibration amplitude from 95μm to 75μm.