Arc fault detection method and system

Abstract

The invention provides a fault arc detection method and system, and relates to the field of arc detection. The fault arc detection method is used to detect whether there is a fault arc in the line to be tested. Monitor the target component of the current in the line under test: define multiple time periods and sample the target component multiple times in each time period to obtain a set of sampling data, so that the multiple time periods correspond to multiple sets of sampling data respectively. It is necessary to perform fast Fourier transform on a set of sampled data in each period to obtain the spectral data of each period. Perform similarity calculation on two sets of spectral data corresponding to any two adjacent time periods to obtain a similarity value, and thereby calculate multiple similarity values ​​from multiple sets of spectral data corresponding to multiple time periods. If one or several similarity values ​​among the plurality of similarity values ​​are not within the predetermined threshold range, it is determined that there is an arc fault in the line to be tested.

Description

technical field [0001] The invention mainly relates to the field of arc detection, more specifically, to an arc monitoring system and an arc monitoring method for detecting a DC arc phenomenon applied to a photovoltaic power generation system. Background technique [0002] With the shortage of traditional energy and the development of power technology, photovoltaics have received more and more attention, and photovoltaic energy must meet safety regulations in power application. Arc is a gas discharge phenomenon, and the spark generated by the flow of electric current through an insulating medium such as air is the manifestation of gas discharge. Detecting arcs and proactively taking countermeasures are key elements in keeping PV energy systems under safe regulations. Although the industry tries its best to find the laws and commonalities of the arc phenomenon in order to find the accurate detection method of the arc, the unavoidable fact is that it is difficult to provide a...

AI Technical Summary

Problems solved by technology

[0006] All in all, because the spectral characteristics of the arc are varied, it is a very difficult task to judge whether there is a real fault arc purely from the spectral characteristics: the main reason is that there is currently no unified conclusion on the standard of the fault arc parameter characteristics as the comparison target , it is of little significance to formulate standard arc parameter characteristics; moreover, the actual detected current parameter information will inevitably have more or less natural errors, which are the reasons why the arc cannot be detected or the arc is falsely reported

Images