Rotor Bar Breaking Fault Diagnosis for Motor Based on Wavelet Packet Frequency Band-Energy Reconstruction
Xiaojie Wu · Electric Machines and Control Application · 2010
Compared with the main frequency,the feature frequency(1 ±2s)f of the fault signal of broken rotor of asynchronous motor has smaller amplitude and was easily drowned.So based on the study of the characteristics of wavelet packet decomposition and reconstruction,the distribution regularity of the frequency band of wavelet packet decomposition-tree was discussed.Sym8 wavelet was selected as wavelet basis.When the motor stator current signals were decomposed at twelfth frequency scales,whether the rotor bars have been broken or not can be determined by energy reconstruction of the fault characteristic frequency band signal.Used this method,the impact on the component of fault features by the fundamental frequency can be well to avoid.Fault feature were more obviously and minor rotor broken bars fault can be detected.Simulation and experimental results showed that the method was correct and effective.