Any faults associated with the transmission lines must be detected and isolated promptly to maintain a reliable. The aim of this this technical article is to cover the most important principles of four fundamental relay protections. Digital and numerical distance protection relays may have up to five or six protection zones, some set to sense in the reverse direction. It provides both primary and backup protection by its zonal settings correctly coordinated between distance relays. Pdf mho distance relay of transmission line high voltage. Distance relays are often used in the protection of the transmission lines connected to the wind farms. To avoid the loss of discrimination with the zone 1 protection of the following line section, zone i distance is set at 80 to 90 % of the line and not 100%. The siprotec 7sa522 relay provides fullscheme distance protection and incorporates all functions usually required for the protection of a power line. The impact of modern developments in digital technology has been felt in many areas of power system protection.
Apr 17, 2016 a distance relay scheme uses only local voltage and current measurements for a bus and transmission line. Fundamental overcurrent, distance and differential. Sep 01, 2018 there is one type of relay which functions depending upon the distance of fault in the line. Distance protection aspects of transmission lines equipped with series compensation capacitors clint t. The reach of such relays is therefore affected by the changing network conditions. Article pdf available march 2019 with 1,059 reads how we measure reads. Distance protection is one of the most used protective principles for transmission lines. First of all, the secondary currents and voltages that are applied to the distance protection relay are filtered and processed in the analog input module and provide. Mainly intended to cover the entire length of the protected line length and set to operate instantaneously i. Distance relay protection for short and long transmission line. For 110kv transmission lines, only three pole tripping shall be provided. Introduction distance relays have been successfully used for many years as the most common type of protection of transmission lines.
Transmission lines are a vital part of the electrical distribution. Three zone protection by using distance relays in simulink. Features include a fourshot recloser, patented capacitance voltage transformer cvt transient overreach logic to enhance security of zone 1 distance elements, and overcurrent elements with directional control, monitoring, and metering. A distance relay measures the impedance of a line using. Principles and characteristics of distance protection. Now assuming that pu impedance of all transmission lines in above fig 22. Because of this we set the relay to measure, or reach, some impedance less than the full length of the line setting zone 1 of up to 85% may be safe and the 1520% safety margin ensures that there is no risk of the zone 1 protection overreaching the protected line due to those errors and inaccuracies. Keywordsthree stepped distance relay, numerical relay, protection of transmission line, relay software, advantech device usb4711a. Protection of lines or feeder august 31, 2018 february 24, 2012 by electrical4u as the length of electrical power transmission line is generally long enough and it runs through open atmosphere, the probability of occurring fault in electrical power transmission line is much higher than that of electrical power transformers and alternators. Saad abstractthis paper presents the design of a mho relay model for the protection of two parallel. Double circuit transmission line fault distance location. The protection challenges presented by threeterminal lines include the following. Distance relays are generally used for phasefault primary and backup protection on subtransmission lines, and on transmission lines where highspeed automatic reclosing.
Application of phase and ground distance relays to three. Why are overcurrent relays not used for primary protection of ehv lines in spite of the fact that instantaneous over current relays exist. The distance relay using the transmission line impedance measurement identifies the type and location of the fault. Slyslyg 60160 phase and ground distance relays slyg61 p similar to slyggia except lineto neutral polarized slyg62p similar to slyg62a except lineto neutral polarized slyg63p similar to slyg63a except lineto neutral polarized for use in single pole trip and reclose schemes. As the length of electrical transmission line is generally long enough and it runs through open atmosphere, the probability of occurring fault in electrical power transmission line. Knowledge based approach for transmission line distance. Because of infeed and outfeed effect the, the relay may sense fault in 100% length of line even though the location of. For this reason the relay setting must consider this effect, some relays have algorithms to compensate, but it is necessary to use the current of the parallel.
Distancedifferential protection of transmission lines. Distance relays used for protection of transmission lines have problems of underreach, overreach and maloperation due to high impedance faults. Distance protection for transmission lines siprotec. Transmission line protection principles ge grid solutions. Distance relays need fault levels are higher on high voltage transmission lines faults need to be cleared rapidly to avoid instability, and extensive damage advantages. Distance protection aspects of transmission lines equipped. It can be concluded from the results that keywords.
Distance relays need fault levels are higher on high voltage transmission lines faults need to be cleared rapidly to avoid instability, and extensive damage advantages the impedance zone has a fixed impedance reach greater instantaneous trip coverage with security greater sensitivity easier setting calculations and coordination. Fundamental overcurrent, distance and differential protection. Overcurrent protection has found widespread use in distribution utility and industrial systems. This study aims to minimize the disruption in the reconfiguration of malang raya transmission lines. The complexity of protecting threeterminal transmission. The relay is designed to provide fast and selective fault clearance on transmission and subtransmission cables and overhead lines with or without series capacitor compensation. Mho relay for protection of series compensated transmission lines a. Since the impedance of a transmission line is proportional. The traditional distance relays which have been widely applied to transmission line calculate the impedance to the fault using the fundamental frequency component of the local voltage and local current 1 2.
Pdf digital distance protection of transmission lines in the. Mho relay for protection of series compensated transmission lines. Rel650 line distance protection substation automation. Keywords artificial neural network,distance relay, fault resistance, matlab i. A distance relay for the protection of transmission lines is usually designed on the basis of fixed settings. Transmission lines distance protection using differential. Pdf the advanced application of artificial neural network was introduced recently in protection of transmission lines in electric power systems. Common settings for three forwardlooking zones of basic distance relay protection are shown in the following paragraphs. Abstractthis paper is a tutorial on the protection of mutually coupled transmission lines. Distance relay or impedance relay working principle types. Sssc located in the middle of the transmission line cause to divide trip characteristics of distance relay. We use distance protection in many transmission lines.
Pdf the implementation of distance protection relay in. Protection of radial feeder in radial feeder, the power flows in one direction only, that is from source to load. The distance relay using the transmission line impedance measurement identifies the. The impedance per mile is fairly constant so these relays respond to the distance between the relay location and the fault location. Calculation of distance protection settings in mutually. However, any relay tester can perform successful endtoend tests with a basic a basic understanding of transmission line protection or 21 impedance protection along and. Knowledge based approach for transmission line distance relay. Introduction transmission lines are a vital part of the electrical distribution system, as they provide the path to transfer power between generation and load.
It is desired that a distance relay cover most of the. Jul 03, 2014 however, any relay tester can perform successful endtoend tests with a basic a basic understanding of transmission line protection or 21 impedance protection along and some preparation before. The implementation of distance protection relay in transmission lines. In the case of parallel lines, the mutual coupling of these lines can cause distance relays to under reach and over reach. Why zone1 setting 80% and zone2 150% in distance protection. Summers abstract in order to meet the high demand for power transmission capacity, some power companies have installed series capacitors on power transmission lines. Transmission lines can vary in length from several hundred feet to several. Transmission line relay loadability sequential clearing for transmission line faults compromises in the ability of the protection to detect faults compromises in relay coordination between the threeterminal line protection and the protection. These relays are known as distance relay or impedance relay. The pazsd methodology employs current coefficients to adjust the zone settings of the relays during infeed situation. More specifically, the relay operates depending upon the impedance between the point of fault and the point where relay is installed. Pdf distance relay protection for short and long transmission line. Series compensated transmission line protection using. Aug 31, 2018 protection of lines or feeder august 31, 2018 february 24, 2012 by electrical4u as the length of electrical power transmission line is generally long enough and it runs through open atmosphere, the probability of occurring fault in electrical power transmission line is much higher than that of electrical power transformers and alternators.
Transmission lines are a vital part of the electrical distribution system, as they provide the path to transfer power between generation and load. Distance relays can be used to protect the transmission lines or power transformers7. It is shown that the relay is capable of tracking the apparent impedance of a transmission line, as it experiences a short circuit, with a speed and accuracy which are. Rel670 transmission line distance protection abb group. Protective relays, associated communication systems, voltage and current sensing devices. The addition of directionality extends the application of overcurrent protection to looped lines. The solution method proposed in 10 uses the monte carlo method to estimate. It provides faster protection as compared to overcurrent relay. Calculation of apparent impedance and distance relay.
Distance protection is a nonunit system of protection, which measures the impedance between the relay location and the point where the fault is incident and compares it with the set value. Transmission lines operate at voltage levels from 69kv to 765kv, and are ideally tightly interconnected for reliable operation. Mar 20, 2019 in this post you will get to know everything about the distance protection for the transmission lines. A new adaptive high speed distance protection scheme for power transmission lines english pdf. Protection scheme0protection scheme for transmission lines as per cbip guidelines should have two independent high speed main protectionschemes two stage over voltage protection sensitive idmt directional ef relays auto reclose relay suitable for 1 ph3ph with deadlinecharging and synchro check reclosure. Keywords artificial neural network, distance relay, fault resistance, matlab i. Pmu based adaptive zone settings of distance relays for. Distance protection relay is widely spread employed for the protection of highvoltage ac transmission line and distribution lines. This paper discusses the installation planning of distance relay protection systems in 150 kv malang raya transmission system reconfiguration. They have replaced the overcurrent protection because of the following reasons. Altuve, and fernando calero, schweitzer engineering laboratories, inc. Experience with a digital distance relay algorithm, which also utilizes a digital lowpass filter, is presented.
The complexity of protecting threeterminal transmission lines. Apply the sel311c relay for protection, reclosing, monitoring, and control of transmission lines. Introduction electrical energy generated at remote locations is delivered using transmission lines. For this reason the relay setting must consider this effect, some relays have algorithms to compensate, but it is necessary to use the current of the parallel line which adds complexity to the installation. Index terms relay application, transmission line protection introduction ieee standard c37. The relion product family offers the widest range of products for the protection, control, measurement and supervision of power systems. Rel650 line distance protection your best choice for costefficient line protection applications rel650 offers an optimum, offtheshelf, readymade application solution for the protection of single breaker connected power lines and cables. Nonpilot distance protection of transmission lines power. In this post you will get to know everything about the distance protection for the transmission lines. As the impedance of a transmission line is directly proportional to its length, it can easily be concluded that a distance relay can only operate if fault is occurred within a predetermined distance or length of line.
Jan 04, 2015 endtoend testing can appear to be a daunting task. An excellent reference on the protection of transmission lines with distance relays is the ieee std c37. Principles and characteristics of distance protection these relays may sometimes be set based in percentages of the line impedances, for example a typical setting for zone 1 is 80% of the impedance of the line in order to not reach the remote end, the zone 2 can be set at 120% of the impedance of the line in order to dependably overreach the line, zone 3 sometimes are disabled or set to cover an adjacent line. Rel670 optimized for transmission applications rel670 ieds intelligent electronic device provide versatile protection, monitoring and control functionality with maximum flexibility and performance optimized for transmission overhead lines and cables. This webinar brought to you by the relion product family.
The purpose of protective relays and system is to operate the correct cb so as to disconnect only the faulty equipmentckt. Distance protection for transmission lines siprotec 7sa522. Line protection with distance relays 295 distance relaying should be considered when overcurrent relaying is too slow or is not selective. Distance relay protection system planning on malang 150 kv. Khincha department of electrical engineering indian institute of science bangalore, india 560012 email. However, any relay tester can perform successful endtoend tests with a basic a basic understanding of transmission line protection or 21.
Knowledge based approach for transmission line distance relay coordination ravikumar b. Because of infeed and outfeed effect the, the relay may sense fault in 100% length of line even though the location of fault is actually not in 100% of line. This type of feeders can easily protected by using either definite time relays or inverse time relays. Transmission line distance protection explained in detail. This allows the impedance of the line to be lowered, thus yielding. Distance relays are generally used for phasefault primary and backup protection on subtransmission lines, and on transmission lines where highspeed. There are mainly two types of distance relay definite distance relay. These coefficients are calculated in phasor data concentrator pdc at system protection. A distance relay scheme uses only local voltage and current measurements for a bus and transmission line. Protection of transmission lines distance protection by, rohini haridas assistant professor, dept of electrical engineering, ssgm college of engineering,shegaon 2.
Distance protection is widely used in the protection of ehv and uhv transmission lines in view of the fact that it can provide fast fault clearance and system coordination. Dec 26, 2015 protection of transmission lines distance protection by, rohini haridas assistant professor, dept of electrical engineering, ssgm college of engineering,shegaon 2. Apr 25, 2012 protection scheme0protection scheme for transmission lines as per cbip guidelines should have two independent high speed main protectionschemes two stage over voltage protection sensitive idmt directional ef relays auto reclose relay suitable for 1 ph3ph with deadlinecharging and synchro check reclosure. Now a days, numerical distance relays have been used widely replacing the. Distance relay performance is defined in terms of reach accuracy and operating time. A abstractehvuhv long transmission lines have large distributed capacitance which has significant effect on the operation of.
Pdf selective, highspeed clearance of faults on high voltage transmission lines is critical to the security of the power system. Article calculation of distance protection settings in. This paper proposes phasor measurement unit pmu based adaptive zone settings of distance relays pazsd methodology for protection of multiterminal transmission lines mtl. Calculation of apparent impedance and distance relay tripping characteristics in ehvuhv transmission line with and without capacitance jayachandra s1, sivakumar g2 1,2j. The development of electromechanical and solid state relays with mho characteristics can be considered as an important factor.