On-line diagnosis method of mechanical fault for gas insulated switchgear

Abstract

The invention discloses an on-line diagnosis method of mechanical fault for a gas insulated switchgear, and belongs to the technical field of power transmission and transformation equipment conditionmonitoring. The method takes the opening and closing operation of a breaker as an excitation source, a sensor can be placed on a to-be-monitored member, and vibration signals can be extracted; and S-transform energy equalization based vibration signal time-frequency plane segmentation thought needs to determine an appropriate segmentation ruler. The method can divide a frequency sub-band and a time sub-band and extract the energy values of each characteristic subinterval under a normal and fault state by adopting a normalized vibration frequency energy density spectrum and instantaneous energydensity spectrum; and the energy values of the characteristic subinterval can be taken as a data set, and classification and identification can be performed on faults by adopting an SVM optimized bya genetic algorithm. The method can effectively diagnose the GIS mechanical faults and enhance the safety and reliability of GIS operation, and has important theoretical and practical values.

Description

technical field [0001] The invention relates to the technical field of intelligent substations, in particular to an on-line diagnosis method for mechanical faults of a gas-insulated combined switchgear (GIS). Background technique [0002] With the increase of grid capacity and voltage level, serious accidents caused by GIS failures will directly threaten the safe operation of urban power grids and may lead to large-scale power outages. As the key equipment of the power system, the reliable operation of GIS is of great significance to the safe, economical and stable operation of the power system. [0003] According to statistics, GIS mechanical failures account for 39.3% of the total failures, of which operating mechanisms such as circuit breakers account for 35.4% of mechanical failures. It can be seen that mechanical failure is one of the main factors affecting the reliability of GIS operation. The main method of mechanical fault research is mainly based on the vibration ...

AI Technical Summary

Problems solved by technology

[0004] In the current research, scholars at home and abroad mostly focus on the fault diagnosis of circuit breakers, and do not pay enough attention to faults in other parts of GIS (except circuit breakers), such as loose internal and external connections.

In addition, the applicability of existing methods needs to be improved

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