Design And Research Of A New Fault Arc Detection Device

With modern electrical equipment widely used in various places, electricalaccident due to the aging or damage of insulation is increased gradually. Currentlyelectrical fire in the whole fire accident has accounted for a large proportion, and itwill be intensified in the future. Therefore, research and prevention of electrical fireshave also been imminent. In the vast majority of low-voltage distribution systems,especially in low-voltage distribution cabinet, electrical fire monitoring system hasbeen among the more common applications. Among them, the electrical fire detectionfocused on over current, residual current, and temperature testing. As for thedistribution cabinet in tandem arc fault detection methods and products are notcommon. Focus of this study is in accordance with national standards of arc faultdetection in electrical fire monitoring system published by National StandardizationManagement Committee and some testing and design for arc fault detection is done.The summary of the background, domestic and international current situationand development trend of arc fault detection is made by this article,. And the maindisadvantages of early warning system of fault arc on the market at present is putforward. Then the difficulty and the key technology of fault arc detection andobjective and significance of the system design is analyzed.Then physical characteristic of fault arc and electrical properties is analyzed,especially physical characteristics of arc light and arc sound and voltage electricalcharacteristics. According to these characteristics, technology requirements of theconstruction of fault arc detection test platform and the associated design is putforward. In the test platform a large number of tests respectively on fault arc current,light and sound are carried out. The current test is the use of pure resistance, pureinductive and resistive inductive load for extraction and analysis of fault arc currentwaveforms and current characteristics is obtained in order to find the method to detectarc fault. The tests of arc sound and arc light are mainly made on different electrodeshapes, different sizes of electrode gap and the distance between sensor and electrodeprobe. The oscilloscope is used to observe whether the arc light and the arc soundsignal generate. the arc light and the arc sound characteristics is found out, so as toachieve the purpose of detection. Furthermore, the theory of using multi sensor detection technology in the faultarc detection is proposed. Research of basic principle and hierarchy method of multisensor detection technology is done. Then the method of fault arc detection isdiscussed. The Bias decision theory is analyzed and the concrete realization method isdiscussed. Multiple signal of fault arc is used to make soft decision informationfusion and get the optimal judgment. The detection of fault arc is completed.Finally, the hardware and software design of arc fault detecting device is made.According to the different functions of the system is divided into different modules.The software and hardware of the corresponding module is designed. And a lot oftesting on the corresponding device is done. And implementation shows that thedevice can detect and monitor effective on fault arc.