ISSN (Print) : 2320 – 3765 ISSN (Online): 2278 – 8875 International Journal of Advanced Research in Electrical, Electronics and Instrumentation Engineering (An ISO 3297: 2007 Certified Organization) Vol. 4, Issue 11, November 2015 Copyright to IJAREEIE DOI:10.15662/IJAREEIE.2015.0411035 8788 Series ARC Fault Detection Using ARC Model and Discrete Wavelet Transform Renjini Raveendran 1 , Aparna Thampi 2 PG Student [Power System], Dept. of EEE, Saintgits Engineering College, Kottayam, Kerala, India 1 Assistant Professor, Dept. of EEE, Saintgits Engineering College, Kottayam, Kerala, India 2 ABSTRACT: Arc faults mainly occur because of electrical problems such as aging cables and loose connections. Generating high temperature and discharging molten metal, arc faults finally lead to electrical fires. Every year such fires bring great loss and damage. It is identified that conventional protecting technique is unable to break a circuit in the situation when a brief arc fault occurs and the arc current is below thermal or instantaneous trip levels. In this paper a new method is proposed for the detection of residential series arc fault . Firstly, suitable arc model is used to simulate series arc fault. Then based on fault detection algorithm the fault features are extracted using a signal processing technique called Discrete Wavelet Transform(DWT). Then by comparing different wavelets, db4 were found appropriate for extracting arc-fault features. The last feature also involved the use of thresholding, peak detection, and relay triping. MATLAB were used to build and simulate arc-fault model. KEYWORDS: Series arc fault model, Discrete wavelet transform, thresholding, peak detection I.INTRODUCTION During a typical year, home electrical problems account for 67,800 fires, 485 deaths, and $868 million in property losses. Electrical fire accidents have become a very important part of fire accidents. Conventional circuit breakers and fuses play an effective role in protecting residential electrical circuits from over-current and short-circuit conditions. But they cannot prevent fire accidents caused by arc faults especially series arc fault. Arc faults normally take place due to wiring problems. It is the reason for 40 000 home fires in the U.S. annually. Mainly there are two types of arc faults exist: series and parallel. The first type shown in Fig. 1 is the most abundant and occurs when the single power conductor breaks. Maximum arc current is then limited by the load current due to the series connection, which is definitely smaller than the CB current rating and depending on the load and, hence, the arc current may or may not produce a significant amount of heat to create a fire[1] . Fig. 1. Series arc-fault condition. The parallel arc fault shown in Fig. 2 occurs between the neutral/ground and phase conductor, when the insulator is damaged due to mechanical, temperature stress, or aging[2] . In this case, high-impedance arc first melts and carbonizes the insulator, and later the low-impedance current path is formed. The path emerges from excessive heat, and if left uninterrupted, it could ignite a fire.