Circuit breaker contact temperature-rise detection method based on GIS casing body temperature measurement

Abstract

The invention relates to a circuit breaker contact temperature-rise detection method based on GIS casing body temperature measurement. The method comprises the steps that 1) the ambient temperature, internal pressure and load current of a GIS circuit breaker under a working condition are acquired; 2) a three-dimensional space multi-physics coupling model of contact heating in the GIS circuit breaker is established to acquire the function relationship between the internal contact temperature rise delta T of the GIS circuit breaker under the current working condition and the maximum temperaturerise delta Tw of a temperature rise sensitive area corresponding to the internal contact on the external surface of the casing body, wherein the function relationship is delta T=f (I0, T0, P0, delta Tw), I0 is the load current, T0 is the ambient temperature and P0 is the internal pressure; 3) the temperature rise distribution of the external surface of the GIS circuit breaker casing body under theworking condition is acquired, and the maximum temperature rise of all temperature rise sensitive areas on the outer surface of the GIS casing body is recorded; and 4) the temperature rise of the internal contact of the GIS circuit breaker is calculated under the working condition is calculated based on the function relationship. Compared with the prior art, the method provided by the invention has the advantages of high accuracy, high security and the like.

Description

technical field [0001] The invention relates to the field of overheating fault detection of high-voltage power transmission and transformation equipment, in particular to a method for detecting temperature rise of circuit breaker contacts based on GIS housing temperature measurement. Background technique [0002] GIS (Gas Insulated Switchgear, gas-insulated metal-enclosed combined electrical appliances) equipment is increasingly widely used in power systems due to its outstanding advantages such as miniaturization, high reliability, and strong flow capacity. However, when the internal conductor is in poor contact, its tight sealing and compact structure can easily lead to serious heating of the conductor under load current, and the temperature rise is too high, which in turn accelerates the aging of the insulating material, resulting in a decrease in insulation performance and causing major power grid accidents such as short circuits. Therefore, it is of great significance t...

AI Technical Summary

Problems solved by technology

The loop resistance measurement method cannot detect live equipment, and cannot determine the number and location of faulty contacts

There is currently no clear criterion for partial discharge detection methods, and the relationship between overheating and partial discharge has not been thoroughly studied. There is a possibility that partial discharge cannot be detected when the contacts are overheated

Regular hand-held infrared thermal image detection can only detect the surface temperature of the GIS circuit breaker shell, and it is greatly affected by weather and human subjective factors; It is not feasible to modify the shell structure of GIS for the equipment under operating conditions

The fiber grating sensor can judge whether the internal contact is overheated by detecting the temperature change of the shell, and can detect the live equipment, but it cannot accurately measure the internal contact temperature

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