变频电机绝缘潜在故障对电压波形的影响研究
Research on impact of potential insulation faults in variable frequency motors on voltage waveforms
摘要
为探究变频电机潜在故障的预测方法,文章以两电平变频器驱动的牵引电机为研究对象,采用仿真分析与试验相结合的方法,系统研究了不同绝缘电阻值和不同故障位置对相对地电压与中性点对地电压的影响规律.结果表明:相对地电压开始畸变的临界绝缘电阻值取决于电机绕组对地电容和变频器频率;当故障点位于绕组首端线圈时,故障点相对地电压波形与其余两相波形的振荡状态差异最为显著,此时中性点对地峰值电压较正常值升高约60%;随着故障点向中性点方向移动,三相对地电压波形逐渐趋于一致,中性点电压畸变峰值也接近正常峰值电压.上述规律可为变频电机绝缘故障的电压特征提取与早期预测提供理论依据.
To investigate potential fault prediction methods for variable frequency motors,this paper takes a traction motor driven by a two-level frequency converter as the research object,and studies the influence rule of different insulation resistance values and fault locations on the phase-to-ground voltage and neutral-point-to-ground voltage through a combination of simulation analysis and test.The results are as follows:the critical insulation resistance value at which the phase-to-ground voltage starts to distort depends on the ground capacitance and converter frequency of the motor windings;when the fault point is located at the starting coil,the difference in oscilla-tion characteristics between the phase-to-ground voltage waveform of the faulty phase and that of the other two phases is the most pro-nounced,at which the neutral-point-to-ground peak voltage increases by about 60%compared to the normal value.As the fault point ap-proaches the neutral point,the three-phase-to-ground voltage waveforms become more similar,and the distorted peak value of the neu-tral-point voltage gradually approaches the normal peak voltage.The above rule provides a theoretical basis for voltage feature extraction and early prediction of insulation faults in variable frequency motors.
年，卷(期)：
2026, (1)
分类号：
U264.1
TM34
机标分类号：
TM711
TM301.2
TM464
在线出版日期：
2026年6月8日
基金项目：
2023YFB3507503:国家重点研发计划，
