Fault location is an important application among intelligent monitoring and outage management tasks used for realization of self healing networks, one of the most attractive features of smart grids. The data gathered from various intelligent electronic devices (IEDs) installed throughout the power system could be utilized for smart approaches to locating faults in both transmission and distribution systems. This paper discusses issues associated with improving accuracy of fault location methods in smart grids using an abundance of IED data. Two examples of how the gathered data from different IEDs is used to improve fault location accuracy in transmission and distribution systems are discussed in detail.

Smart Fault Location for Smart Grids

The paper presents a new approach to the location of fault in the high-voltage power transmission line, relying on the application of the support vector machine and frequency characteristics of the measured one-terminal voltage and current transient signals of the system. The extensive numerical experiments performed for location of different kinds of faults of the transmission line have proved very good accuracy of fault location algorithm. The average error of fault location in a 200-km transmission line is below 100 m and the maximum error did not exceed 2 km.

Accurate fault location in the power transmission line using support vector machine approach

Many methods for fault location using synchronized phasor measurement have been reported in literature. Most of these methods use voltage and current measurements at one or both ends of a transmission line. Accuracy of current measurement is limited by the accuracy of the current transformers (CT) used. This paper describes a fault-location method for transmission lines using only synchronized voltage measurements at both ends of the line, eliminating the inherent error due to CT. The method can be applied to transposed and untransposed lines. The method is tested using results from a steady state fault-analysis program and EMTP.

Fault location on a transmission line using synchronized Voltage measurements

This paper presents a critical review on different application of Phasor Measurement Units (PMUs) in electric power system
networks incorporated with FACTS controllers for advanced power system monitoring, protection, and control. Also this paper
presents the current status of the research and developments in the field of the applications of PMUs in electric power system
networks incorporated with FACTS controllers. Authors strongly believe that this survey article will be very much useful to the
researchers for finding out the relevant references in the field of the applications of PMUs in electric power system networks
incorporated with FACTS controllers.

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Applications of phasor measurement units (PMUs) in electric power system networks incorporated with FACTS controllers

This paper presents a general fault-location method for large transmission networks which uses phasor measurement unit (PMU) voltage measurements where the injected current at a fault point can be calculated by using the voltage change and its relevant transfer impedance on any bus. A two-stage fault-location optimization model is proposed, along with defining a matching degree index. The first stage is the fault region identification stage, which uses the matching degree index to determine the suspicious fault region in order to reduce the search area. The second stage is used to identify the exact fault line and fault distance. A method to determine optimal PMU placement is also proposed in this paper. Case studies verify that the proposed fault-location algorithm and optimal PMU placement scheme can locate faults in large transmission networks quickly and accurately without requiring fault-type classification or fault phase selection.

PMU-Based Fault Location Using Voltage Measurements in Large Transmission Networks

Earlier work at Texas A&M University led to the development of transmission line fault location algorithms that were based on synchronized sampling of the voltage and current data from the two ends of the line. The line models used in the algorithms were based on lumped parameter models for electrically short lines, or lossless distributed parameter models for electrically long lines. In this paper, the lossless line model is modified to account for the series losses in the line. The line model equations are then solved in the time domain to accurately locate the fault. Testing of the modified algorithm is performed on a power system belonging to the Western Area Power Administration. Extensive EMTP based simulations are used to generate data that are supplied as inputs to the fault location algorithm. To make the testing as realistic as possible, detailed models of instrument transformers are used in the simulation of the various fault cases.

/pdf/fault-location-using-the-distributed-parameter-transmission-3o1g3uivh2.pdf

A. Gopalakrishnan

Papers

Fault location using the distributed parameter transmission line model