EMC of Railways - Lightning Protection
Project members:
Prof. Rajeev Thottappillil (Main supervisor)
• Dr. Thorsten Schütte, (past member, formerly with Rejlers Västerås)
• Dr. Ziya Mazloom (past member)
• Dr. Surajit Midya (past member, presently with Bombardier, Stockholm)
• Dr. Nelson Theethayi (past member, presently with Bombardier, Västerås)
• Dr. Yaqing Liu (past member, presently EMC consultant, USA)
• Dr. Mihael Zitnik (past member, presently with Bombardier, Stockholm)
Sponsor: Banverket, Bombardier Transportation [1998-2006]
Brief description:
The signalling and train control systems in modern railways are highly automated. Digital electronics can realize a great amount of intelligence and flexibility in the control functions and they find increasing use in railway systems. However, there is always a concern about the reliability and safety issues because of the low threshold destruction energies associated with modern electronics. Before the advent of modern electronics, key components in the signal and control networks were electromechanical and were largely insensitive to electromagnetic disturbances such as transient events caused by lightning. Therefore the design of signal and control network in those times was not always done according to the strict rules of electromagnetic compatibility. Later, individual sub-systems in the network were being replaced by units containing modern electronics, and new functionality such as Automatic Train Stop (ATS), Automatic Train Control (ATC) etc. were being added. These developments made the signal and control system more vulnerable to lightning transients.
During thunderstorms the railway systems are subjected to lightning electromagnetic pulses (LEMP), either due to direct attachment of lightning to any part of the overhead conductor system or due to the induced voltages created in the conductor system due to lightning strikes nearby. Part of the lightning surge energy find its way to the electronics causing upset and destruction.
Main objective of this research is to create computationally efficient and verified models for the interaction of lightning with the electrified railway systems and to suggest effective lightning protection so as to eliminate or minimise traffic stoppage and delays during thunderstorms. The model should be including the rails and overhead conductor system above finitely conducting ground, interconnections between these conductors and connections to earth, non-linearities like insulator flashovers, lumped components like track circuits, booster and auto transformers, buried communication cable near the tracks etc..
Related publications (selected):
Ziya Mazloom, Nelson Theethayi, and Rajeev Thottappillil, A Method for Interfacing Lumped-Circuit Models and Transmission-Line System Models With Application to Railways, IEEE TRANSACTIONS ON ELECTROMAGNETIC COMPATIBILITY, VOL. 51, NO. 3, page 833-841, AUGUST 2009.
Theethayi, N., R. Thottappillil, G. Diendorfer, M. Mair, H. Pichler, Currents in Buried Grounding Strips Connected to Communication Tower Legs during Lightning Strikes, IEEE Transactions on Dielectrics and Electrical Insulation Vol. 15, No. 4; pp. 1153-1161, August 2008.
Nelson Theethayi, Vladimir A. Rakov and Rajeev Thottappillil, Responses of Airport Runway Lighting System to Direct Lightning Strikes: Comparisons of TLM Predictions With Experimental Data, IEEE Transactions On Electromagnetic Compatibility, Vol. 50, No. 3, pp. 660-668, August 2008.
Nelson Theethayi, Yoshihiro Baba, Farhad Rachidi and Rajeev Thottappillil, On the Choice Between Transmission Line Equations and Full-Wave Maxwell's Equations for Transient Analysis of Buried Wires, IEEE Trans. on Electromagnetic Compatibility, Vol. 50, No. 2, 2008, pp. 347-357.
Nelson Theethayi and Rajeev Thottappillil, On Reducing the Lightning Transients in Buried Shielded Cables Using Follow-On Earth Wire, IEEE Trans. on Electromagnetic Compatibility, Vol. 49, No. 4, November. 2007, pp. 924-927.
Nelson Theethayi and Rajeev Thottappillil, Some Issues Concerning Lightning Strikes to Communication towers, Journal of Electrostatics, Vol. 65, Issues 10-11, October 2007, pp. 689-703.
Nelson Theethayi, Ziya Mazloom and Rajeev Thottappillil, Technique for Reducing Transient Voltages in Multiconductor-Shielded Cables, IEEE Trans. on Electromagnetic Compatibility, Vol. 49, No. 2, May 2007, pp. 434-440.
Nelson Theethayi, Rajeev Thottappillil, Mario Paolone, Carlo Alberto Nucci and Farhad Rachidi, External Impdeance and Admittance of Buried Horizontal Wires for Transient Studies Using Transmission Line Analysis, IEEE Trans. on Dielectrics and Electrical Insulation, Vol. 14, No. 3, pp. 751-761, June 2007.
Nelson Theethayi, Rajeev Thottappillil, Yaqing Liu and Raul Montano, Important Parameters That Influence Crosstalk in Multiconductor Transmission Lines, Electric Power Systems Research, Vol. 77, Issue 8, 2007, pp. 896-909.
Per Anders Lindeberg, Ziya Mazloom, Nelson Theethayi, Rajeev Thottappillil, Thorsten Schutte, Blitzeinwirkungen auf Oberleitungsund Signalanlagen in Schweden (in German), eb-Elektrische Bahnen, 105, 2007, pp. 67-80.
Yaqing Liu, Nelson Theethayi and Rajeev Thottappillil, Investigating the validity of existing definitions and empirical equations of effective length/area of grounding wire/grid for transient studies, Journal of Electrostatics, Vol. 65, Issues. 5-6, 2007, pp. 329–335.
Nelson Theethayi, Rajeev Thottappillil, Tegegne Yirdaw, Yaqing Liu, Thomas Götschl and Raul Montano , Experimental Investigation of Lightning Transients Entering a Swedish Railway Facility, IEEE Trans. on Power Delivery, Vol. 22, No. 1, January 2007, pp. 354-363.
Theethayi, N., Y. Liu, R. Montano, R. Thottappillil, M. Zitnik, V. Cooray, V. Scuka, Theoretical study on the consequence of a direct lightning strike to electrified railway system in Sweden, Electric Power System Research, 74, 267-280, 2005.
Liu. Y, Theethayi. N, and Thottappillil. R, An Engineering Model for Transient Analysis of Grounding System Under Lightning Strikes: Nonuniform Transmission-Line Approach, IEEE Transactions On Power Delivery, Vol. 20, No. 2, April 2005, pp. 722 – 730.
Manyahi, M.J., R. Thottappillil and M. Leijon, Transfer of transient surge voltage through XLPE cable winding transformer (Dryformer) circuits, International Journal of Electrical Power & Energy Systems, Volume 27, Issue 8, Pages 602-609, October 2005.
Manyahi, M.J., and R. Thottappillil, Simplified model for estimation of lightning induced transient transfer through distribution transformer, International Journal of Electrical Power & Energy Systems, 27, 241-253, N0.4, 2005.
Manyahi, M.J., M. Leijon and R. Thottappillil, Transient response of transformer with XLPE insulation cable winding design, International Journal of Electrical Power & Energy Systems, 27, 69-80, January 2005.
Theethayi, N., Y. Liu, R. Montano and R. Thottappillil, On the Influence of Conductor Heights and Lossy Ground in Multi-Conductor Transmission Lines for Lightning Interaction Studies in Railway Overhead Traction Systems, Journal of Electric Power System Research, 71, 186-193, 2004.
Liu, Y., Nelson Theethayi , R. Thottappillil, R. M. Gonzalez and M. Zitnik, An improved model for soil ionization around grounding system and its application to stratified soil, J. Electrostatics, 60, 203-209, 2004.
Thottappillil, R., Electromagnetic Pulse Environment of Cloud-to-Ground Lightning for EMC studies, IEEE Trans. On Electromagnetic Compatibility, 44, 203-213, 2002.
Liu, Y., M. Zitnik, and R. Thottappillil, An improved transmission-line model of grounding system, IEEE Transactions on Electromagnetic Compatibility, 43, 348-355, 2001.
Galvan, A., V. Cooray, and R. Thottappillil, A technique for the evaluation of lightning-induced voltages in complex low-voltage power-installation networks, IEEE Transactions on Electromagnetic Compatibility, 43, 402-409, 2001.
Theethayi N, Mazloom Z, Thottappillil R, Lindeberg P A, Schütte T, “Lightning interaction with the Swedish railway network”, Railway Engineering 2007, June 20-21, London, UK.
Mazloom Z, Theethayi N & Thottappillil R, “Influence of Discrete Series Devices on Crosstalk Phenomena in Multiconductor Transmission Lines” 18th International Zurich Symposium on Electromagnetic Compatibility, 2007, Munich, Germany.
Theethayi N & Thottappillil R, “Lightning Interaction with Electrified Railways, in Tutorial on EMC aspects of Lightning”, 2007 IEEE EMC International Symposium on Electromagnetic Compatibility, Honolulu, Hawaii, USA, 2007.
Nelson Theethayi and Rajeev Thottappillil , Simple Expressions for External Wire Impedance and Admittance for Lightning Current Pulse Propagation in Buried Wires, Fourth ASIA-PACIFIC Conference on Environmental Electromagnetics, CEEM 2006, Dalian University of Technology International Convention Center, Dalian, China Aug-l-4, 2006.
Theethayi, N., R. Thottappillil, On reducing the internal voltages and currents due to lightning transients in buried shielded cables, Proceedings of the 28th International Conference on Lightning Protection, pp. 1322-1327, ISBN 4-9902110-2-2, Kanazawa, Japan, Sept. 18-22, 2006.
Theethayi, N., R. Thottappillil, Lightning Interaction with Electrified Railways, in Tutorial on EMC aspects of Lightning, 17 th International Zurich Symposium on Electromagnetic Compatibility, Singapore, 27 th Feb- 3 rd March, 2006.