Asynchronous motor rotor broken bar fault judgment method with electric signals and vibration signals integrated

Abstract

The invention discloses an asynchronous motor rotor broken bar fault judgment method with electric signals and vibration signals integrated, which belongs to the field of motor fault judgment. The method comprises the following steps: an acquisition instrument acquires voltage and current data through a current clamp and a voltage clamp, current spectrum analysis is carried out, if the current signals are normal, no broken bar fault happens to the motor rotor, and if the current signals are abnormal and when one side band appears at each position with a twice slip frequency difference from a power frequency, the next step is carried out; voltage spectrum analysis is carried out, if the voltage signals are normal, no broken bar fault happens to the motor rotor, if the voltage signals are abnormal and when one side band appears at each position with a twice slip frequency difference from the power frequency, vibration signal analysis is carried out, and whether broken bar fault happens to the motor is judged. In view of the problem that error judgment exists in a motor current signal analysis method in the asynchronous motor rotor broken bar fault in the prior art, a mode of sequentially judging the stator current, the stator voltage and the vibration signals is adopted, the rotor broken bar fault is detected, and the error judgment rate is reduced.

Description

technical field [0001] The invention relates to the field of motor fault judgment, in particular to a method for judging a broken bar fault of an asynchronous motor rotor by integrating electric signals and vibration signals. Background technique [0002] With the advancement of modern science and technology and the increasing scale of power systems, motors play an increasingly important role in modern industrial production. Motor failure will not only damage the motor itself, but also affect the normal operation of the entire system. In severe cases, it may even endanger personal safety, causing huge economic losses and significant social impact. Therefore, the diagnosis of motor faults is of great significance and engineering practical value. Studying the monitoring and fault diagnosis technology of high-voltage asynchronous motors is of great significance to prevent the occurrence of high-voltage asynchronous motor faults, find and eliminate faults in time, ensure the rel...

AI Technical Summary

Problems solved by technology

[0004] At present, the method for judging the broken rotor bar of an asynchronous motor is mainly based on detecting the current of the motor, and the analysis method of the motor current signal has its own defects: this method is affected by the load level and operating frequency

Its shortcoming is that the selection of test points directly affects whether there is a fault in the broken bar in a timely and effective manner, and the surface area of ​​the motor shell is relatively large. How to select the test points is not disclosed in this patent.

Its shortcoming is that the invention still relies on the stator current signal to judge the fault of the broken rotor bar. Once the stator current is affected by the load fluctuation, there is still the possibility of misjudgment through the control strategy of the stator voltage and current coupling.

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