Induction motor rotor broken bar fault diagnosis method based on wavelet packet support vector machine

Abstract

An induction motor rotor broken bar fault diagnosis method based on a wavelet packet support vector machine, and the method comprises the steps of preprocessing detected induction motor rotor broken bar fault stator current, and filtering out the noise component included in the fault stator current; performing wavelet packet decomposition on the de-noised current signal to obtain a fault current signal component of each sub-band; reconstructing a wavelet packet decomposition coefficient and calculating the sum of signal energy in each frequency band; performing normalization processing on thesignal energy in each frequency band and constructing a feature vector; constructing a support vector machine model; dividing the feature vector into a training sample and a prediction sample, training the support vector machine model by using the training sample, testing the trained model by using the prediction sample, judging a fault type to which the signal corresponding to the feature vectorbelongs, and obtaining the diagnosis accuracy of the test set as a verification result of the model. According to the invention, the limitation that signal sampling time is too long, load fluctuationinterference is caused, and slight faults cannot be detected is avoided.

Description

technical field [0001] The invention belongs to the field of fault diagnosis of induction motors, and relates to a method for diagnosing a broken bar of an induction motor rotor based on a wavelet packet support vector machine, which solves the problem of extraction and discrimination of fault signals, and decomposes the fault signal of a broken bar of an induction motor rotor based on a correlation algorithm The extraction method is combined with the support vector machine to realize the diagnosis of the broken bar fault of the induction motor rotor. Background technique [0002] Induction motors have the advantages of durability, low price, and easy maintenance, and have been widely used in electric power, mining, shipbuilding, and metallurgy industries. Due to the complex working environment of induction motors, they usually face long-term continuous operation, frequent Braking and starting and complex working environment and other harsh tests are prone to various failure...

AI Technical Summary

Problems solved by technology

However, when the induction motor is running, the slip s is generally very small, so at the initial stage of the rotor broken bar fault, (1±2s)f 1 The component amplitude is also very small, it is difficult to judge whether the fault occurs or not

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