功率频谱分析在电机故障诊断中的应用

Application of Power Spectrum Analysis in Diagnosis of Motor Fault

把定子绕组本身当作探测线圈来检测转子的故障,在采样定子电流的同时提取线电压,从而得到电机的功率信号,并进行频谱分析。通过对功率信号进行频谱分析,在线诊断异步电机转子故障。推导笼型电机出现转子断条时,故障特征在功率频谱中的表现形式。该方法只需采样单相电流电压,与同时提取三相电流的扩展PARK矢量方法相比,能降低硬件费用,突出断条故障特征。实验结果验证该方法有效。

The paper introduces the power spectrum analysis and its application in motor fault diagnosis. We regarded stator winding as detection coil to detect the rotor faults, sampled stator current and extracted line voltage, so obtained the power signal of motor and did spectrum analysis. On-line diagnosis for rotor faults in induction motors was conducted through frequency spectrum analysis method; the manifestation of fault feature in power spectrum was emerged when motor faults such as rotor broken bar appeared. Comparing with extended PARK＇s vector approach （EPVA）, the method only needs to sample the single phase current and voltage, and can reduce hardware costs and highlight the features of rotor broken-bar fault. Experiment result proves the method is effective.