Research On Series Arc Fault Signals And Its Diagnosis Technology

With the increasing consumption of electrical energy, fire caused by electricalappliance failure has done a lot of damages both to peop le’s lives and their property.Especially the ones triggered by arc fault, which can not be recognized using traditionalcircuit interrupters, make it hard to cut the power in time. In recent years, some foreigncountries have devised AFCI (Arc Fault Circuit Interrupter) installed at the powerdistribution terminals to prevent fire, for it is capable to detect arc fault immediately. Whilethe corresponding development of AFCI suitable for domestic application is at its earlystage, a complete arc fault database is still ongoing. Our work mainly focuses on arc faultdata acquisition, detecting difference between normal working current and arc fault currentby various methods, and providing the basis for the detection of arc fault.This paper briefly introduces the relationship between arc fault and electrical fire atfirst, and so are the related works and task significance. Then the deliberation of arc faultand its mechanism will be presented, followed by its category and characteristic.An experiment platform to simulate arc fault was set up under standard UL1669,based on which situations of occurring arc fault in serial connection is simulated, the arcfault current of linear load and nonlinear load then is apprehended, and the correspondingnormal current data is also collected as control group. A simple time domain analysis of thedifference between these current is also given.For failing to detect arc fault in time domain, analysis under Fourier transform andWavelet transform is conducted and the difference points are detected in both domains.Then the arc fault detection methods based on Fast Fourier Transform and WaveletTransform are proposed to facilitate detecting arc fault.