Low-voltage arc fault detection method and device

Abstract

The invention discloses a low-voltage arc fault detection method and device. The method includes: sampling and processing voltage between a firing line and a null line of a protected circuit to acquire high-frequency pulse signals and sampling and processing current of the protected circuit to acquire current half-wave signals; selecting a sampling time window which includes multiple fundamental frequency cycles; judging the fundamental frequency cycles in the sampling time window one by one, and when G.30+H.20+M.50 is more than 50000, judging that one suspected fault signal is generated from one fundamental frequency cycle; continuously making statistics on the number N of suspected fault signals in the sampling time window, and when N is greater than or equal to 9, judging that a suspected arc fault occurs; judging the fundamental frequency cycles generating the suspected fault signals one by one, and when L.40+S.30+V.30 is more than 50000, judging the arc faults occur. The arc faults are monitored in real time through analysis of the high-frequency pulse signals and current characteristics, the arc faults and interference can be effectively distinguished, reliability is higher, and false tripping actions are reduced.

Description

technical field [0001] The invention relates to the field of arc fault detection in low-voltage power distribution systems, in particular to a low-voltage arc fault detection method and device that are not easily disturbed by changes in normal operating current waveforms. Background technique [0002] With the rapid development of science and technology, the degree of electrification of modern households continues to increase, the number of electrical equipment and household appliances increases dramatically, household electricity consumption continues to increase, and fire accidents caused by electrical failures are becoming more and more frequent, which has caused huge losses to the society. According to relevant statistics, the accident rate of electrical fires ranks first among all kinds of fires, reaching 30.3%. In severe and extraordinarily large fires, this proportion is even greater, as high as 46.1%. Arc faults are caused by poor contact, loose connections, aging i...

AI Technical Summary

Problems solved by technology

At present, the field of arc fault circuit breakers for household circuits is still in the research and development stage in China. Although a few companies have developed arc fault circuit breakers for household circuits, their circulation in the market has not really started, and their reliability has not yet been improved. verification of

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