Fault location method applied to transmission lines of general configuration Silvio Giuseppe Di Santo ⇑ , Carlos Eduardo de Morais Pereira Department of Electrical Energy and Automation Engineering, University of Sao Paulo, Av. Prof. Luciano Gualberto, trav. 3 n° 158, 05508-900 SP, Brazil article info Article history: Received 27 January 2014 Received in revised form 4 January 2015 Accepted 11 January 2015 Available online 6 February 2015 Keywords: Fault location Transmission lines Optimization abstract Power quality is an important concern once automation is present in almost all industrial process. Since fault occurrences affects the power quality considerably, in this paper is proposed a new fault location method applied to transmission lines constituted of any configuration, as example double circuit, untransposed sections, and multiple derivations. In order to locate the fault, the method uses voltage and current phasors gathered from terminals with measures, however the method does not need these measures from all terminals. The proposed method is composed of three blocks to locate the fault, which are: Algorithm’s Main Con- trol, Grid Scanning Process, and Objective Function’s Minimization Process. A large number of simulations were conducted and the results show the accuracy and efficiency of the method, even in cases of high impedance faults. Ó 2015 Elsevier Ltd. All rights reserved. Introduction The demand for power quality is increasingly becoming a rule in almost all industrial processes, where automation is highly pres- ent. These processes demand for an adequate voltage level and power frequency. Hence, locating faults in transmission lines with accuracy is an important need, since the repair time, in the case of permanent faults, affects considerably the reliability of the system as well as causes economic damages by the industrial processes stopping. In the literature there are many fault location methods, where it may be cited those that use data from one terminal [1–5], from two terminals [6–11], and those that use data from more than one ter- minal in transmission lines with derivations [12–17]. In the followings paragraphs will be briefly discussed some fault location methods. The fault location method proposed in [2] is applied to parallel transmission lines. It is based on transmission line’s distributed parameters model and require voltage and current measures from only one terminal. The method determine the fault point by means of the sequence networks (positive, negative and zero sequences), where are calculated the sequence voltages at the fault point in terms of the voltage and current measures and of the unknowns point and resistance of the fault. A concern about this method is that an increase in the fault location errors may occur when untransposed transmission lines and unknown tapped loads is present. In [6] is proposed an adaptive fault location method that depends on synchronized measures gathered by Phasor Measure- ments Units (PMUs), being independent of measures that shall be provided by electric utilities. This method is applied only to single circuit transmission lines transmission without tapped loads. The method proposed in [12] is based on traveling waves. Using the waves’ arrival time in the terminals it is built a matrix whose coefficients are the ratio between the fault distance and the length of the branch formed by the pair of terminals considered. With this matrix the author determines the local of the fault and after the fault distance. The main concern about this method is that mea- surements from all terminals may not be available and as in [6] the method is applied only to single circuit transmission lines. In [13] is proposed a two-stage fault location optimization model, along with defining a matching degree index. The method could be used in large transmission networks. It is also proposed the corresponding PMU placement strategy. Once the method uses only voltages in the calculations, the results obtained it may be wrong when faults with high impedance occur. The method proposed by [14] locates faults on transmission lines constituted of single circuit. In the fault location, the method uses the current and voltage phasors measured at local and remote terminals of the transmission line. With these phasors, are calcu- lated the current and voltage phasors at the tap points and so it http://dx.doi.org/10.1016/j.ijepes.2015.01.014 0142-0615/Ó 2015 Elsevier Ltd. All rights reserved. ⇑ Corresponding author. Tel.: +55 11 97503 5310; fax: +55 11 3091 5719. E-mail address: silviogiuseppe@pea.usp.br (S.G. Di Santo). Electrical Power and Energy Systems 69 (2015) 287–294 Contents lists available at ScienceDirect Electrical Power and Energy Systems journal homepage: www.elsevier.com/locate/ijepes