The Research On Detection Method Of Low Voltage Series Arc Fault

The level of electrification is becoming higher and higher with the rapiddevelopment of electrical technology, and the threat of electrical fire is getting moreand more serious too. Throughout the recent fire accident statistics, Electrical fire hasbeen the first of the whole fire accident. Electrical fire accident can be divided intooverheating type and arc type, when there is an arc fault occurred, even with small arccurrent will it produce local high temperature, that can ignite the combustible nearbyeasily and lead to a fire. Existing electrical fire protection technology can prevent theoverheating type electrical fire well, such as the overheating type electrical firescaused by flow or leakage, however, when it comes to an arc type electrical fire, itcan’t provide comprehensive prevention. The developed countries such as Europe andthe United States have developed an arc fault circuit breaker because of theconcealment and high risk of arc fault, and the installation of this circuit breaker isforced by law. The domestic experts have already pay high attention to the researchon the detection method of arc fault, but the work is still in the primary stage. So,it isof great significance to do further research of arc fault and develop an arc fault circuitbreaker which is suitable for Chinese electrical characteristic.In this paper, firstly, an arc fault experimental platform was built with references tothe domestic existing research and the United States standard-UL1699, whichincludes the design of electric arc generator and the development of the dataacquisition system based on NI Data Acquisition Card. Low voltage series arc faultexperiments were carried out under the utility (220V,50Hz) power supply.In theexperiment different typical load were connected with arc generator in series, thecurrent and voltage of arc generator device were recorded during the experiments.Theindependent component analysis(ICA) method was introduced to arc fault research,Independent elements were separated from experimental data of series arc fault byFastICA separation algorithm.The characteristic harmonics of arc were summed upafter the harmonic analysis of separation results. According to the characteristicharmonic the higher harmonic ratio of current was analysised, and the typical change characteristics during arcing were summarized. A rapid and effective detectionscheme of series arc fault was proposed according to the analysis results above.Finally, a series arc fault detection device was designed, and a prototype is made. Theoffline verification testing was carried out affter online debugging, the test resultsshow that the series arc fault detection device can eliminate the interference of typicalloads and operating arc, and detect series arc fault accurately.A series arc fault detection device that can detect series arc fault of specific circuitpromptly and effectively is designed in this paper, and it will own certain referencevalue for the research of arc fault detection technology in our country.