Research On Arc-fault Detection Device And System

In recent years, as China’s economic development, the electricity load of resident isincreasing heavily sharply, and the new electricity equipment type and quantity are on therise, the working state of the low voltage distribution network is more and morecomplicated, which puts forward stricter requirement for the safe. The traditional circuitprotection device: circuit-breaker, residual current operated protective device, overcurrentprotective device, and short circuit protection device. Generally, they can protect powerlines, however, if the current is less than the rated current which will not work. So thedevelopment of arc fault detector has important practical significance.First this paper analyzes the arc current characteristics under different load conditions,and summarizes the typical characteristics of the low-pressure arc current: zero-currentarea, a large number of high-frequency harmonics, etc. Secondly, analysis of the Fouriertransform and Wavelet transform, Fourier transform is a global conversion. Wavelettransform is a partial conversion, so in signal processing, wavelet transform is better thanFourier transform. So determined using mathematical statistics and the combination ofwavelet transform method to identify the arc. Then, in order to test the detector designmeets the design requirements, using a new type of fault arc generating device, it has agood consistency and repeatability. Finally, the arc-fault detection device is designed, anda prototype is produced. The arc fault diagnosis program is verified by experiment basedon the test of the prototype. The test result shows that the proposed scheme can identifythe arc fault.In this paper, the research work is based on experimental data. Through mathematicalstatistics and the combination of wavelet transform method is used to identify the arc. Thearc fault diagnosis method proposed is proved to be reliable and practical by testing, and itmay provide directive significance and application value to the protection for the arc fault.