Current calibration method and system for power distribution network overhead line monitoring device

Abstract

The invention provides a current calibration method and system for a power distribution network overhead line monitoring device, and the method comprises the steps: calibrating a power distribution network monitoring device through two times of calibration, and making rough adjustment in a mode that the calibration coefficients corresponding to 11 calibration gears are written into an acquisitionunit during one-time calibration; during secondary calibration, adopting a least square method to carry out segmented calibration to realize fine adjustment while when the load current sampling valueand the actual output current sampling value of the current source are obtained; adopting a mode of continuously reading to achieve multiple times and averaging so that the abnormal condition caused by electromagnetic interference is effectively avoided, and in the calibration process, each calibration gear or calibration current adopts the actual current size instead of a theoretical value, so that the abnormal condition caused by an unstable current source is effectively avoided. Through two times of calibration, the load current precision of the fault indicator can be controlled within 0.5%, thereby greatly improving the accuracy and reliability of fault detection.

Description

technical field [0001] The invention relates to the technical field of power supply and distribution, in particular to a current calibration method and system for an overhead line monitoring device of a distribution network. Background technique [0002] In recent years, the monitoring of grounding and short-circuit faults of overhead lines in domestic medium-voltage distribution networks has become the research focus of distribution network monitoring. A monitoring device is installed on the distribution line. The monitoring device is composed of an acquisition unit and a collection unit. Send monitoring information, waveform files, and fault detection data. Since the fault judgment mainly depends on the change of the load current of the monitoring device, the current accuracy is directly related to the fault judgment result. Therefore, how to improve the current accuracy of the distribution network overhead line monitoring device to improve the accuracy and reliability o...

AI Technical Summary

Problems solved by technology

[0003] The purpose of the present invention is to provide a current calibration method and system of a distribution network overhead line monitoring device, which aims to solve the problem of low current accuracy and large error in the monitoring of the overhead line monitoring device in the prior art, and realize the improvement of the distribution network overhead line. Accuracy and reliability of fault discrimination

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