Oscillation blocking and backup protection tripping method based on wide area information

Abstract

The invention discloses an oscillation blocking and backup protection tripping method based on wide-area information. The method comprises 1) an oscillation blocking method for identifying an oscillation center based on wide-area information and 2) a backup protection tripping method based on wide-area information. The oscillation blocking method for identifying the oscillation center based on the wide-area information comprises the steps that 1.1) if a protection device is started for 150ms and is not output, an oscillation blocking element is started; 2) a protection center station collects measuring information of all substations based on a wide-area communication network, and occurrence of system oscillation is judged; and 1.3) according to the judgment result of the step 1.2), the center station calculates a line on which the oscillation center is positioned and searches the substations connected with the line if oscillation occurs, and the center station transmits an open protection signal to the substations connected with non-oscillation lines; and the center station transmits the open protection signal to all the substations if oscillation does not occur. Backup protection is performed by effectively utilizing wide-area measuring information so that sensitivity of non-oscillation line protection in failure period is enhanced, and motion speed of backup protection is enhanced simultaneously.

Description

【Technical field】 [0001] The invention belongs to the field of transmission line protection, and in particular relates to an oscillation blocking method and a backup protection tripping method based on wide-area information. 【Background technique】 [0002] Oscillating blocking elements play a very important role in distance protection. When the fault processing program of the distance protection device does not exit within 150ms, the oscillation blocking element will first block the first and second stage functions of the distance protection. This method can effectively prevent the protection from malfunctioning when the transient stability is destroyed, but the disadvantage is that if a fault occurs during the protection blocking period, it cannot trip selectively and at a faster speed, and may cause a large-scale power outage in the system , or even system collapse. Some scholars proposed real-time blocking and opening distance protection according to the oscillation pro...

AI Technical Summary

Problems solved by technology

For example, 150ms after oscillation, it will automatically switch to oscillation blocking, which not only reduces the sensitivity of distance protection in non-oscillation conditions, but also reduces the sensitivity of distance protection in systems other than the oscillation center; as another example, the backup protection should be a backup for the main protection. , that is, the circuit breaker can be tripped immediately when the main protection refuses to operate, and the upper-level circuit breaker that cooperates with the rejecting circuit breaker can be tripped as soon as possible after confirming that the circuit breaker refuses to operate. However, the staged coordination principle of backup protection is often based on The grid structure is coordinated step by step, and the quick movement is guaranteed

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