Numerical Relay Based 220 kV Transmission Line Backup Distance Protection at Pipri West Grid- A Case Study

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Adnan Soomro
Muhammad Ovais Raza
Muhammad Hammaduddin
Muhammad Saad Aslam
Abdul Moeed Saadat
Syed Muhammad Shakir
Syed Saad Amin


This case study presents the working, testing and commissioning of the 220 kV backup distance protection schemes employed on the Pipri West Grid of Karachi Electric Limited (KEL). The paper discusses protection systems in transmission lines and the technical issues with electromechanical and static relays. Current status of relays in Pakistani transmission network and the need for their up gradation to modern numerical relays have been emphasized. The 220 kV backup distance project of Karachi Electric (KE) uses LZ96 static relay that has been replaced with Siemens Siprotec 4 7SA522 numeric distance relay. These newly replaced relays has features of telecommunication, monitoring, control, and power swing blocking functions. This paper also present the problems encountered in conventional distance protection. Desirable features of distance protection are obtained via tele-protection. Information transmitted from one end to the other end of the line via tele-protection is also analyzed. The parameterizing of numerical relays is done with Digitalizer Simulator (DIGSI) software and finally testing results are reported using Instrumentation System Automation (ISA) TEST SET.

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Soomro, A., Muhammad Ovais Raza, Muhammad Hammaduddin, Muhammad Saad Aslam, Abdul Moeed Saadat, Syed Muhammad Shakir, & Syed Saad Amin. (2019). Numerical Relay Based 220 kV Transmission Line Backup Distance Protection at Pipri West Grid- A Case Study. University of Wah Journal of Science and Technology (UWJST), 3, 1-14. Retrieved from


[1] W.P. Davis. Analysis of faults in overhead transmission lines, M.S. thesis, California State University, California, 2012.
[2] A. Haddad and F. W. Doug. Advances in High Voltage Engineering, IET, 2004.
[3] R. J. Marceau, T. Donald, M.C. Gillis and R. Sana. Asymmetric Operation of AC Power Transmission Systems the Key to Optimizing Power System Reliability and Economics, Presses inter Polytechnique, 2006.
[4] A.T.M. Yesansure and T. G. Arora. Numerical quadrilateral distance relay, International Journal of Innovative Research in Science, Engineering and Technology, Vol. 2(7), pp. 2920-2927, 2013.
[5] S.H. Horowitz and A.G. Phadke. Power system relaying, 4th edition, John Wiley and Sons, 2014.
[6] M. Eissa. Ground distance relay compensation based on fault resistance calculation, IEEE Transactions on Power Delivery, Vol. 21(4), pp. 1830-1835, 2006.
[7] A. Stosic, A. Marusic and J. Havelka. Transmission lines protection using siprotec numerical relays, Energija, Vol. 66, pp. 165-183, 2017.
[8] M.J. Domzalski, K. P. Nickerson and P. R. Rosen. Application of MHO and quadrilateral distance characteristics in power systems (relay protection), 7th International Conference on Developments in Power System Protection, 2011, pp.555-558.
[9] D.G. Philip and A. Rajendran. Development of a multi-characteristic distance relay, International Conference on Advancements in Power and Energy, 2015, pp. 176-181.
[10] M. Harikrishna. Performance of quadrilateral relay on EHV transmission line protection during various faults, International Journal on Control System and Instrumentation, Vol. 1(1), pp. 1-6, 2010.
[11] Alstom Grid. Network Protection and Automation Guide. Available online at /07/network-protection-and-automation-guide-book.pdf on March 24, 2018.
[12] A. Abdelmoumene and H. Bentarzi. A review on protective relays developments and trends, Journal of Energy in Southern Africa, Vol. 25(2), pp. 91-95, 2014.
[13] L. A. Esteves, G. Caicedo and F. Murcia. Field tests for assessing electrical protection performance regarding electromechanical protection relays, Ingenieria e Investigacion, Vol. 32(3), pp.71-75, 2012.
[14] D.S.Baker. Application considerations of static overcurrent relays a working group report, IEEE Transactions on Industry Applications, Vol. 33(6), pp.1493-1500, 1997.
[15] J. Polimac and A. Rahim. Numerical relays–where are we now, 19th International Conference on Electricity Distribution, 2007, pp.1-4.
[16] D.L. Ransom. Upgrading relay protection: be prepared for the next replacement or upgrade project, IEEE Industry Applications Magazine, Vol. 20(5), pp. 71-79, 2014.
[17] F.M.A. Hussain, N. Khan, N. Mariun and S. Mahmod. Microprocessor based distance relay, National Power Engineering Conference, 2003, pp.43-46.
[18] D.G. Philip and A. Rajendran. Numerical conic distance relay, International Conference on Innovations in Information, Embedded and Communication Systems, 2015, pp.1-5.
[19] Bharat heavy electrical limited, Handbook of switchgears, Tata McGraw Hill Education Private Limited, 2005.
[20] A.L.P.d. Oliveira. Numerical distance protection performance analysis in short and long transmission lines using real time digital simulation, IEEE/PES Transmission and Distribution Conference and Exposition Latin America, 2008, pp. 1-6.
[21] Siemens, IPROTEC 7SA522 Distance Protection Relay for Transmission Lines. Available online at https://www.building on March 24, 2018.
[22] A.Venkatesh, K. S. Swarup. Investigating the performance of a symmetrical component distance relay, Proceeding of National Power Systems Conference, 2012, pp. 1-7.
[23] D.K. Singh, A.K. Singh and S.R. Mohanty. An adaptive transmission line protection and modelling of numerical distance relay with analog antialiasing filter, International Conference on Industrial Technology, 2017, pp. 388-393.
[24] A. Saber, A. Emam and H. Elghazaly. Wide area backup protection scheme for transmission lines considering cross country and evolving faults, IEEE Systems Journal, Vol. 99, pp. 1-10, 2018.
[25] M. Younas and S. Qureshi. Analysis of blackout of national grid system of Pakistan in 2006 and the application of PSS and FACTs controllers as remedial measures, International Conference on Electrical Engineering, 2007, pp.1-6.
[26] Damien, S.R. Tholomier. Improving the Performance Of Distance Protection During Wide Area Disturbances. Available online at on March 24, 2018.
[27] S. Zafar, Y.R. Fizzah, H. Haider and Sana. analysis of the awareness of present day undergraduate electrical engineering students about contemporary technologies, 2nd International Electrical Engineering Conference, 2017, pp. 31-35.
[28] I.A. Group, DRTS-6 Automatic Three-Phase Relay Test Set Manual. Available online at /prodotti/DRTS%206/pdf/inglese/SIE10156-DRTS6.pdf on March 24, 2018.

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