Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 31743
Static Priority Approach to Under-Frequency Based Load Shedding Scheme in Islanded Industrial Networks: Using the Case Study of Fatima Fertilizer Company Ltd - FFL

Authors: S. H. Kazmi, T. Ahmed, K. Javed, A. Ghani


In this paper static scheme of under-frequency based load shedding is considered for chemical and petrochemical industries with islanded distribution networks relying heavily on the primary commodity to ensure minimum production loss, plant downtime or critical equipment shutdown. A simplistic methodology is proposed for in-house implementation of this scheme using underfrequency relays and a step by step guide is provided including the techniques to calculate maximum percentage overloads, frequency decay rates, time based frequency response and frequency based time response of the system. Case study of FFL electrical system is utilized, presenting the actual system parameters and employed load shedding settings following the similar series of steps. The arbitrary settings are then verified for worst overload conditions (loss of a generation source in this case) and comprehensive system response is then investigated.

Keywords: Islanding, under-frequency load shedding, frequency rate of change, static UFLS.

Digital Object Identifier (DOI):

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2006


[1] M. Anderson and M. Mirheydar, “An Adaptive Method for Setting Underfrequency Load Shedding Relay” in Transactions on Power Systems, Vol. 7. No. 2, May 1992 (Pg. 647 – 653)
[2] Behnam Khaki and Shahram Montaser Kouhsari, “Proper Setting of Underfrequency Load Shedding Relays in Industrial Plants” in IEEE- 978-1-4244-5371-9/10 – 2010
[3] Peter Muganyi, and Charles Mbohwa, “Shutdown Maintenance Drivers under an Integrated and Business Focused” in Int’l Conference on Industrial, Manufacturing, Automation and Mechanical Engineering (IMAME'2013) Nov. 27-28, 2013 Johannesburg (South Africa) pp. 87 – 91
[4] H. Mokhlis, J. A. Laghari, A. H. A. Bakar and M. Karimi, “A Fuzy Based Under-Frequency Load Sheding Scheme for Islanded Distribution Network Conected with DG” in International Review of Electrical Engineering (I.R.E.E.), Vol. 7, N pp. 4992-5000. 4 July - August 2012
[5] M Lukie, I Kuzle and S. Tesnjak , “An adaptive approach to setting under frequency load shedding for isolated power systems with private generation” in 9th Mediterranean Electro technical Conference MELECON 1998 pp. 1122 – 1125 vol. 2
[6] M. S. Sujatha1 and Dr M. Vijay Kumar, “Under frequency load shedding for energy management using anfis/case study” in International Journal of Electrical Engineering & Technology. Volume 4, Issue 2, March – April (2013), pp. 93-104
[7] J. R. Jones and W.D. Kirkland, "Computer algorithm for selection of frequency relays for load shedding," IEEE Computer Application in Power, Jan. 1988, pp. 21-25.
[8] M. NagpaI, A. Moshref, Z. Shukn, .I. T. Vijayan, D. Chan and C. Henvile "Dynamic simulation optimize application of an under frequency load shedding scheme," Western Protective Relay Conference, Spokane, Washington, October 2 1-23, 1997.
[9] Bas Bouman, Eric Alferink , Marco Lusing and Jan Verstraten, “A view on internal arc testing of low voltage switchgear”
[10] Yujin Lim, Hak-Man Kim, Jaesung Park and Tetsuo Kinoshita, “A Load-Shedding Scheme Using Optimization for Proportional Fairness in the Islanded Microgrid” in Communications in Computer and Information Science Volume 256, 2011, pp 235-24
[11] J.A. Laghari, Hazlie Mokhlis, A. B. Halim Abu Bakar , M. Karimi and A. Shahriari “An Intelligent Under Frequency Load Shedding Scheme for Islanded Distribution Network ” in 2012 IEEE International Power Engineering and Optimization Conference (PEOCO2012), Melaka, Malaysia: 6-7 June 2012 (pp. 40 – 45)
[12] R. A. Walling and N. W. Miller, "Distributed generation islandingimplications on power system dynamic performance," in Power Engineering Society Summer Meeting, 2002 IEEE, 2002, pp. 92-96 vol.1.
[13] Hsu, C.T., C. S. and J. K. “The load-shedding scheme design for an integrated steelmaking cogeneration facility” in Industry Applications, IEEE Transactions (Volume: 33, Issue: 3) Page(s): 586 – 592
[14] A. A. Mohd, H. Mohd Hafeez and W. K. Wong, “Static and Dynamic Under-frequency Load Shedding: A Comparison” in 2004 International Conference on Power System Technology - POWERCON 2004 Singapore, 27-24 November 2004 (pp 941-945)
[15] Report of the Task Force on UnderFrequency and Undervoltage Relaying," Underfrequency and Undervoltage Relay Applications to Large Turbine Generators," National Electric Reliability Council, Research Park, Princeton, NJ, July 1978.