Motor monitoring method and system based on symmetrical component method and multi-dimensional index fusion

Abstract

The invention discloses a motor monitoring method based on the symmetrical component method and multi-dimensional index fusion, which includes collecting original three-phase voltage signals and original three-phase current signals; establishing a band-pass filter centered on the fundamental frequency to obtain filtered three-phase Voltage signal and three-phase current signal; obtain the unbalance degree of instantaneous three-phase voltage and three-phase current; perform symmetrical component decomposition based on the filtered three-phase voltage signal and three-phase current signal, and obtain sequence voltage, sequence current and sequence impedance; Obtain the multi-dimensional characteristic comprehensive decision-making index; compare the multi-dimensional characteristic comprehensive decision-making index with the threshold value, if less than, trigger an alarm signal. The present invention is based on collecting three-phase voltage and current signals. The present invention can improve real-time sequence voltage, sequence current and sequence impedance indexes, has higher data resolution ability, and can realize state alarm with higher precision than temperature-based alarm strategy, with sequence voltage, sequence current and sequence impedance as monitoring targets , with ultra-high signal-to-noise ratio and high alarm accuracy.

Description

technical field [0001] The invention relates to the technical field of online motor monitoring, in particular to a motor monitoring method and system based on a symmetrical component method and multidimensional index fusion. Background technique [0002] The reliability and life of motor operation are largely determined by its insulation performance. Therefore, the development of insulation state assessment technology to accurately evaluate the health status of traction motor insulation will help to improve the safety of motor operation, reduce the risk of motor operation, and reduce Reduce maintenance costs and improve maintenance efficiency. [0003] The motor insulation state evaluation technology is divided into offline detection technology and online monitoring technology. The off-line detection technology has developed maturely, and related detection products such as insulation resistance and capacitance test equipment have been very mature, and are widely used in mot...

AI Technical Summary

Problems solved by technology

First of all, the temperature-based online monitoring technology uses the insulation temperature as the monitoring target, and triggers an alarm when the temperature exceeds the preset temperature threshold. Current monitoring requirements for important motors with high real-time, high precision, and high accuracy

Secondly, the online monitoring technology based on the unbalance of three-phase voltage and current takes the instantaneous unbalance of three-phase voltage and three-phase current as the monitoring target, and triggers an alarm when the unbalance exceeds the threshold. Compared with the temperature-based Monitoring technology has greatly improved in terms of real-time performance, precision and accuracy, but the physical meaning is not clear, and there is still a lot of room for improvement in terms of accuracy

Finally, due to the complex electrical characteristics of the insulation, only a single indicator such as temperature and unbalance is used to evaluate the online operation status of the insulation, resulting in a high false alarm rate

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