www.tjprc.org editor@tjprc.org International Journal of Electrical and Electronics Engineering Research (IJEEER) ISSN(P): 2250-155X; ISSN(E): 2278-943X Vol . 4, Issue 5, O ct 2014, 63-74 © TJPRC Pvt. Ltd. A NOVEL METHOD FOR DETECTION OF ELECTRIC TRANSMISSION LINE FAULTS USING DISCRETE WAVELET TRANSFORM NAVEEN GAUR 1 , RAM NIWAS H MAHIA 2 & OM PRAKASH MAHELA 3 1 Principal, Aryan Polytechnic College, Ajmer, Rajasthan, India 2 Research Scholar, Indian Institute of Technology, Jodhpur, Rajasthan, India 3 Research Scholar, IIT Jodhpur, Rajasthan, India 3 Assistant Engineer, RRVPNL, Jodhpur, Rajasthan, India ABSTRACT The power utility companies have been trying to identify and locate three-phase transmission line faults in the minimum possible time in order to prevent economic losses. In the last few decades technology used for power system protection has evolved and shifted from electromechanical devices to solid state and micro-processor based intelligent devices, which require fast and accurate detection of faults in the transmission lines. This paper presents a novel discrete wavelet transform (DWT) based multi-resolution analysis technique for detection of transmission line faults including and without including ground. A comparative study of all types of faults is presented. A test system having generation, load and transmission line in two parts is modeled in MATLAB/ Simulink environment. The MATLAB programming is used for DWT analysis of the faults. KEYWORDS: Fault Detection, Discrete Wavelet Transform, Power System, Transmission Line, Transmission Line Fault 1. INTRODUCTION Transmission and distribution lines are important parts of the electrical power system and provide the path to transfer electrical power from central generating stations to load centers. These lines are susceptible to faults due to continuous environment exposition and switching operations [1]. The performance of power system is affected by faults on transmission lines, which results in interruption by power flow [2]. The fast and accurate detection, classification and location of the transmission line fault must be done to de-energize the faulted line, protecting the power system network from the harmful effects of the fault [3]. The continuous expansion of power networks in both scale and complexity has been imposing a requirement for fast fault clearance to improve system stability and reliability [4]. For the same, efficient and reliable protection techniques have been developed. In [5], authors proposed a digital distance protection scheme for transmission lines based on analyzing the measured voltage and current signals at the relay location using wavelet transform (WT) with multi-resolution analysis (MRA). In [6], authors presented a scheme for the protection of parallel transmission lines in which WT with its magnificent characteristics is employed to detect the disturbances in the current signals during faulty conditions and to estimate the phasors of all the signals as well as to achieve high-speed relaying. The wavelet-based ultra high speed directional transmission line protection has been proposed in [7]. A prototype Kerr Cell has been constructed by the authors in [8] and tested for detecting and identifying faults by