Research On Arc Fault Fast Diagnosis And Protection Device

With the rapid development of national economy and the continuous improvement ofpeople’s living standards, the occurrence probability of electrical accidents also increasedas the electrical equipment and power system became larger and larger, such as arc fault.When arc fault generates in circuit or device, the device itself or flammable objectssurrounding can be easily ignited, resulting in fire accident, causing significant propertydamages and personal injury. It can effectively prevent the occurrence of such incidents toresearch on arc fault rapid diagnostic techniques on line or equipment, detect arc fault fastand timely, and then take appropriate protective measures and cut off the power on line.The uncertainty of location where arc fault probably occurs and the finiteness ofparameters that can be used to diagnose arc fault are the technical difficulties of arc faultreal-time diagnosis, usually diagnosing arc fault only depends on the current of line.Besides, the algorithm of diagnosing arc fault cannot be too complicated and the softwareand hardware condition that required is limited.This obtains the arc fault current parameters of typical loads by arc fault simulationtests, and then analyzes the arc fault characteristics with tests data. According to thephenomenon that arc fault waveform of line current will be distortion of the line currentwaveform without the fault arc, this paper presented a fault arc diagnosis method using thechanges and differences of current waveform before and after the fault arc-the waveformcomparison method. This method is proved to diagnose the fault arc that probably occursin line fast and accurately by the analysis and research on tests data of typical loads.In this paper, the reliability is analyzed on some factors that could affect the arc faultdetection results with waveform comparison method, including load changing, currentharmonic, sampling point unsynchronized and sampling frequency changing. The resultsshow that the arc fault diagnosis method proposed in this paper with the goodcharacteristics of anti-impact above.