Online monitoring and warning method for protective relaying direct-current operating circuit

Abstract

The invention provides an online monitoring and warning method for a protective relaying direct-current operating circuit. The direct-current operating circuit comprises a closing circuit and a tripping circuit. The online monitoring and warning method includes steps of establishing a closing circuit monitoring branch and a tripping circuit monitoring branch respectively; selecting components and setting parameters in the closing circuit monitoring branch and the tripping circuit monitoring branch; detecting current flowing through the closing / tripping circuit monitoring branch to be compared with disconnection alarm current of the closing / tripping circuit, and judging whether the closing / tripping circuit is disconnected or not. The current flowing through the closing / tripping circuit monitoring branch can be monitored online by setting up the closing / tripping circuit monitoring branch, and complete monitoring of the tripping and closing circuits is realized by judging whether circuits are disconnected or not according to the current; by the online monitoring and warning method, all-condition complete monitoring can be realized without influencing normal operation of the system.

Description

technical field [0001] The invention relates to an early-warning method, in particular to an on-line monitoring and early-warning method for a DC operation loop of relay protection. Background technique [0002] Relay protection hardware defects are one of the main reasons for recessive faults, and incorrect protection actions caused by defects in the DC operation circuit account for a relatively high proportion. Therefore, effective monitoring and early warning of the DC operation circuit is to prevent recessive faults. , An important means to reduce the protection of incorrect actions. The poor contact of the DC operation circuit and the circuit breakage are the important reasons for the incorrect action of the protection. The conventional direct monitoring of the traffic light circuit or the indirect monitoring of the position relay normally closed contact in series with the signal circuit belongs to the non-full working condition monitoring. After the circuit breaker is...

AI Technical Summary

Problems solved by technology

The document "Design and Implementation of Circuit Breaker Operation Circuit with Trip Circuit Monitoring" points out a trip circuit disconnection monitoring scheme connected in series with high internal resistance relays, but the closing circuit in this scheme is still a non-full working condition monitoring

At the same time, the concept of intelligent operation box has also been proposed, but the use of intelligent operation box in conventional substations not only increases the complexity of the system but is also uneconomical

At present, there is no mature means to realize the comprehensive and effective monitoring of the DC operation circuit

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