Power distribution network protection AC loop fault monitoring method based on adjacent node comparison

Abstract

The invention discloses a power distribution network protection AC loop fault monitoring method based on adjacent node comparison, and the method is characterized in that the method comprises the following steps: 1, collecting AC operation data of an AC loop based on the type of the AC loop connected to a monitored current protection node in a power distribution network; 2, collecting alternating current operation data on one or two adjacent protection nodes adjacent to the current protection node; 3, based on the alternating current operation data of the current protection node acquired in the step 1 and the alternating current operation data of the adjacent protection node acquired in the step 2, generating a protection alternating current loop fault criterion, and based on the fault criterion, adjusting a protection action for the protection alternating current loop. The fault criterion and logic are simple, the judgment result is accurate, the response speed is high, and the problem of voltage and current criterion failure under special conditions is solved.

Description

technical field [0001] The invention relates to the field of distribution network protection, in particular to a fault monitoring method for distribution network protection AC circuits based on comparison of adjacent nodes. Background technique [0002] In the existing technology, distribution network protection has been widely used in the distribution network as a necessary means to reduce the power outage time of faults in the distribution network, reduce the failure rate of equipment, reduce the scope of power outages, and realize the beneficial effects of distribution network automation. However, the protection actions of the distribution network and the identification of busbar faults in the distribution network are usually only determined based on the electrical quantity data in the current interval. This makes the existing distribution network protection technology still have the following problems. [0003] First of all, in the protective AC circuit with voltage tra...

AI Technical Summary

Problems solved by technology

When the neutral line in the voltage transformer is disconnected, the third harmonic of the voltage will be generated, and the characteristics of this third harmonic are very similar to the fundamental zero-sequence voltage, which will cause the traditional voltage transformer disconnection monitoring logic to be distorted , the accidental blocking of the protection AC circuit occurs

[0004] Secondly, in the protective AC circuit with current transformers, because the realization function of the distribution network determines that its structure has the characteristics of multiple points and wide areas, under the working condition of a large number of circuits connected to the distribution network, the The load current is small, which makes it difficult to distinguish the abnormal current in the protection AC circuit from the current under normal working conditions, so it is difficult to distinguish the fault

With the continuous development and wide application of distributed power supply and power grid technology, the trend of local load balancing is becoming more and more obvious, which will increase the difficulty of identifying abnormal current faults in the protection AC circuit

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