Squirrel-cage three-phase asynchronous motor rotor broken bar fault diagnosis method

Abstract

The invention discloses a squirrel-cage three-phase asynchronous motor rotor broken bar fault diagnosis method comprising the following steps: using discontinuous voltage and current signals to construct an adaptive filter, and filtering fundamental frequency components in the current signals; dividing the filtered stator current in a sliding window mode; and calculating a Prony coefficient, a Prony pole and related parameters of the current signal in each window, extracting amplitudes and frequencies of other frequency components except the fundamental frequency component in each window through a Prony method, and judging whether a frequency value in the current is (1-2s)f1 and (1 + 2s)f1 to determine whether a fault exists or not. According to the invention, the limitation of an adaptivefiltering method on the sampling frequency is made up. Tracking of fluctuation of the motion state of the motor is achieved through the sliding window. The operation data length is reduced, and the diagnosis speed is increased. Diagnosis can be completed only through single-phase current and voltage sampling, and troubleshooting is facilitated.

Description

technical field [0001] The invention belongs to the technical field of fault diagnosis of asynchronous motors, and in particular relates to a method for diagnosing a broken bar fault of a squirrel-cage three-phase asynchronous motor rotor. Background technique [0002] Asynchronous motors play an important role in industrial and agricultural production, and are one of the main consumers of social electric energy. To ensure that their rotors are fault-free is a prerequisite for the normal operation of the motor. [0003] At present, the fault diagnosis method for broken rotor bars of asynchronous motors mainly includes: analyzing the relevant parameters of the motor running state obtained through online monitoring devices or motor running experiments, extracting the fault characteristic components, and determining whether the fault characteristic components exist or not. Whether or not the method fails. The traditional fault diagnosis methods for broken rotor bars include: m...

AI Technical Summary

Problems solved by technology

[0004] To sum up, the existing traditional diagnostic methods have the following defects: they cannot overcome the influence of motor motion state fluctuations; the required data time length is long and the response is slow; the sampling frequency is limited, which affects the detection accuracy, and an effective diagnostic method is urgently needed. A Fast and Fast Diagnosis Method for Broken Bar of Asynchronous Motor Rotor

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