Discrimination and location method of small current ground fault based on fault indicator

Abstract

The invention discloses a small current grounding fault distinguishing and positioning method based on a fault indicator. The method comprises the following steps: time-checking and synchronizing a human collecting unit; synchronously triggering a collecting unit and collecting a current and a voltage; calculating a zero-sequence current, a zero-sequence voltage and a derivative value of zero-sequence voltage time-checking; calculating a zero-sequence current transient-state polarity characteristic value at fault moment and a transient-state polarity characteristic value of the derivative value of the zero-sequence voltage time-checking; calculating a small current grounding fault characteristic value of each fault indicator and judging whether a fault occurs; and positioning a position inwhich the small current grounding fault occurs. The method is capable of, through a local collecting unit and the collecting unit, predicating the small current grounding fault, wherein a remote master station does not need to analyze a large amount of recording data through a complicated algorithm so as to position the grounding fault; and solving an error code problem caused by transmission ofa large amount of the recording data and a cost problem of high data traffic.

Description

technical field [0001] The invention specifically relates to a method for discriminating and locating a small current grounding fault based on a fault indicator. Background technique [0002] With the development of economy and technology and the improvement of living standards, people have higher and higher requirements for the reliability of distribution network power supply. At present, the most frequent faults in the distribution network are short-circuit faults and ground faults. Short-circuit faults have very obvious fault characteristics, so the success rate of short-circuit fault detection is already very high. But the ground fault, especially the small current ground fault, has no obvious fault characteristics and short transient duration, which has become a major difficulty in fault location in the distribution network. [0003] At present, the mainstream small current grounding methods include the externally applied signal source method and the transient wave re...

AI Technical Summary

Problems solved by technology

The disadvantage of this method is that a large amount of wave recording data needs to be uploaded to the main station through the GPRS network, which requires high network stability and real-time performance, and a large amount of data transmission requires traffic costs.

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