Detection method for loose defects of arc contact of extra-high voltage circuit breaker

Abstract

The invention relates to a detection method for loose defects of an arc contact of an extra-high voltage circuit breaker. The detection method comprises the following steps: (1) carrying out micro-distance movement on a circuit breaker contact by virtue of a slow division and combination manner during measurement; (S2) carrying out resistance measurement on multiple points in the route of the arccontact under a static state; (S3) carrying out state quantity significant difference analysis and calculation on a measurement result obtained in the step (S2); and (S4) judging whether the arc contact has the loose defects according to a calculation result in the step (S3). Compared with the prior art, the detection method has the advantages of relatively high accuracy, wide popularization valueand the like.

Description

technical field [0001] The invention relates to the field of detection of circuit breakers, in particular to a method for detecting loose arcing contacts of UHV circuit breakers. Background technique [0002] In recent years, with the construction and operation of a large number of UHV substations, new defects and new problems in the operation and maintenance of UHV equipment have become increasingly prominent. Compared with conventional substations, UHV substations, as the core power supply of a region, once Failure will cause great loss. As an important control and protection device in the power system, the circuit breaker is very important to the power system for its safe and stable operation and accurate and reliable fault removal. In September 2017, according to the annual maintenance plan, a certain UHV equipment was carried out for annual maintenance. After the No. 2 main transformer circuit was overhauled and put back into service, an internal flashover occurred in ...

AI Technical Summary

Problems solved by technology

In September 2017, according to the annual maintenance plan, a certain UHV equipment was carried out for annual maintenance. After the No. 2 main transformer circuit was overhauled and put back into service, an internal flashover occurred in phase B of the 1000kV T022 switch. After rush repairs and replacement of the circuit breaker Resumption of power transmission caused great losses

After disassembly analysis, it was found that the internal arcing contact of the circuit breaker was seriously loose relative to the static side. During the operation of the circuit breaker, the active side arcing contact and the insulating nozzle of the arc extinguishing chamber were damaged by collision, resulting in a serious flashover fault

Due to the lack of maintenance experience and standards, the operating units and equipment manufacturers do not have an effective detection method for defects such as loose arc contacts of circuit breakers. Even if the static arc contacts are seriously loose (the static arc contacts are about to fall ), the two routine tests of the loop resistance test and the mechanical characteristic test during the annual inspection cannot be effectively found

This makes the safe and stable operation of the UHV circuit breaker very passive.

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