رحمن دشتی

Distribution networks are important components of power and energy infrastructure. Today’s distribution networks are vulnerable to different types of faults. To make the electric grid more resilient, it is important to detect and locate faults in distribution lines quickly and accurately. Impedance methods are the most common ways used to locate the faults. In this paper, first possible fault locations are identified using the improved impedance method. Then, its natural frequencies are determined. Since there are more than one possible fault locations, it is necessary to identify the fault section in order to determine the fault location accurately. The fault section and its main location are determined through simulating the fault in each section of possible locations. This is done by small steps and through accommodating the determined frequency to the existing natural frequency registered in the original fault voltage form. The proposed method is applied in Salim’s 11-node network in which effect of fault inception angles, effect of different resistors and fault type are tested. Accuracy and efficiency of the proposed method has been verified.