变负载工况下高速永磁电机转子动力学特性试验研究

Tests for dynamic characteristics of a high speed permanent magnet motor's rotor under different loads

设计搭建了由动静压混合气体轴承支承的45 k W高速永磁电机转子试验平台,基于该试验平台开展了接入不同额定负载工况下,轴系受到变不平衡磁拉力的动力学特性试验。共进行5次试验,供气压力均为0.80 MPa,接入额定负载分别为0 k W,15 k W,30 k W,60 k W,145 k W。接入额定负载增大,相同转速下轴系受到不平衡磁拉力增大,低频涡动出现转速提前,当接入额定负载为60 k W,145 k W时,转子单一低频涡动频率发展为双低频振动特性,并出现碰摩降速现象。试验结果表明增加电机额定负载,轴系受到不平衡磁拉力增加,造成低频涡动出现转速降低,稳定阈值降低,且在大额定负载下,单一涡动频率发展为双低频振动频率,出现轴系的碰摩失稳故障特性。

A test platform for a 45 k W high speed permanent magnet motor＇s rotor was established,and the rotor was supported with hybrid gas bearings. Dynamic characteristics of the shaft system under different loads were tested for 5 times based on this test platform. Bearing gas supply pressures were 0. 8 MPa,and the motor rated load were 0 k W,15 k W,30 k W,60 k W and 145 k W for test 1-test 5. It was shown that the unbalanced magnetic pull increases with increase in rated load under the same rotating speed; the rotating speed for low frequency whirl occurrence decreases from 607. 42 Hz to 500 Hz when the rated load increases from 0 k W to 145 k W; when the rated loads are 60 k W and 145 k W,the rotor＇s single low frequency whirl feature changes into the double-low frequency feature,and the rotating speed for rubbing occurrence decreases.