This guide outlines the techniques and application considerations for determining the location of a fault on ac transmission and distribution lines. This document reviews traditional approaches and the primary measurement techniques used in modern devices: one-terminal and two-terminal impedance-based methods and traveling wave methods. Application considerations include: two- and three-terminal lines@ seriescompensated lines@ parallel lines@ untransposed lines@ underground cables@ fault resistance effects@ and other power system conditions@ including those unique to distribution systems. This guide discusses various approaches to determine fault location@ with emphasis on automatic methods performed by microprocessor devices. The following are some techniques used to determine fault location: a) Microprocessor devices b) Short-circuit analysis software c) Customer calls (distribution) d) Line inspection A device capable of determining the physical fault location has different requirements than a fault detection device. a) The speed to determine fault location is for human users (seconds or minutes)@ while relays usually need to detect fault within 10 ms to 50 ms. Consequently@ additional information and more demanding and slower numerical techniques become available. b) A best fault data window can be selected to reduce errors. c) Communications enable transmitting data to a remote site using low-speed data communications or supervisory control and data acquisition (SCADA). d) More accurate phasor calculations can be achieved by using digital filtering of the voltage and current samples that would introduce an unacceptable delay for the relaying applications. e) High accuracy is needed for efficient dispatch of repair crews. Unlike protective relays@ which need to detect whether faults are in the zones established by ct locations@ pilot channels@ and reach coordination@ fault location data must be very accurate to save the time and reduce the expenses of the crews searching in bad weather and/or over rough terrain. In this guide@ the following are examined: - Data and equipment required - Common algorithms - Accuracy limitations of one-ended and two-ended impedance-based fault location methods - Traveling wave methods and other methods - Issues regarding distribution systems and underground cables
IEEE C37.114-2004 history
2014IEEE C37.114-2014 Guide for Determining Fault Location on AC Transmission and Distribution Lines
2004IEEE C37.114-2004 Guide for Determining Fault Location on AC Transmission and Distribution Lines