WORLD MEETING ON LIGHTNING

2016

Lightning Performance Research on Mexican High Voltage Transmission

Lines

Carlos ROMUALDO-TORRES, PhD (Eng)

Instituto de Investigaciones Eléctricas

MEXICO

Lightning Performance Research on Mexican High Voltage Transmission Lines

This paper describes: Answer to question 1: Shielding and backflashover results for typical transmission lines. Answer to question 2: The experiences obtained by CFE and IIE during several years of use of surge arresters in transmission and distribution lines.

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Lightning Performance Research on Mexican High Voltage Transmission Lines

Ø  Answer to question 1: Shielding and

backflashover results for typical transmission lines.

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Year   Transmission Line Operating Voltage (kV)

2013  

 2014

230 60 % 45 %

400 56 % 57 %

Transmission line lightning caused failures for 2013 and 2014 years [1, 2]

Lightning Performance Research on Mexican High Voltage Transmission Lines

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Ø  Prediction methods are usually based on Monte Carlo simulation [4]:

Ø  Electrogeometrical model [5, 6] Ø  Travelling wave analysis [7] Ø  To simulate the lightning performance of a

transmission line over a prescribed period of time to determine a failure rate of the lines [8].

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Lightning Performance Research on Mexican High Voltage Transmission Lines

Lightning Performance Research on Mexican High Voltage Transmission Lines

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Figure 1. Electrogeometrical model [5, 9]

Lightning Performance Research on Mexican High Voltage Transmission Lines

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Figure 2. Stroke current at a tower splitting between groundwires and ground [ 5]

Lightning Performance Research on Mexican High Voltage Transmission Lines

Figure 3. Simplified description of the Monte Carlo and Travelling Wave method for shielding and backflasohover calculations [8] 8

Lightning Performance Research on Mexican High Voltage Transmission Lines

Figure 4. 230 kV transmission line under study [9].

F i g u r e 5 . S h i e l d i n g a n d backflashover failures for a 230 kV transmission line based on 1 stroke/ km2/year [9].

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Lightning Performance Research on Mexican High Voltage Transmission Lines

A n s w e r t o q u e s t i o n 2 : T h e experiences obtained by CFE and IIE during several years of use of surge arresters in transmission and distribution lines.

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Lightning Performance Research on Mexican High Voltage Transmission Lines

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Figure 6. Transmission line protecting methods against shielding failures and backflashovers [10, 13].

a) Outage statistic records of the prospect

transmission line, at least of the last five years or before.

b) Grounding resistance measurements along conflictive line areas.

c) Ground flash density along the line. d) Terrain topography through the transmission

line route e) Exposed towers over elevated mountainous

areas with slopes and ravines, long spans and scarce vegetation.

The main philosophy used for the application of surge arresters on transmission lines is as follows [11]:

Lightning Performance Research on Mexican High Voltage Transmission Lines

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Surge arresters are commonly installed as follows [11]:

a)   On critical sections of the line, or in regions with rocky soil (high resistivity)

b)  Structures with high grounding resistance

c) In lines with critical loads connected

Lightning Performance Research on Mexican High Voltage Transmission Lines

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Installation of 230 kV arresters with external series gap

a) Ten surge arresters were installed on

TED-93930-VTP transmission line in 2006. This line is 106 km in length [12].

b) Two critical regions with major lightning

problems were chosen. c) Surge arresters were installed at the outer

phase conductors of the line

Lightning Performance Research on Mexican High Voltage Transmission Lines

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Figure 8. Outages rates for TED-93930-VTP transmission line [3, 13]. Poor performance Better performance

Lightning Performance Research on Mexican High Voltage Transmission Lines

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Table I. Outage rates for TED-93930-VTP transmission line [13]

Lightning Performance Research on Mexican High Voltage Transmission Lines

Transmission line

Outages pear year with no

arresters

Year Arrester installation Outages per

year with arresters

Outage reduction per

year

TED-93930-VTP 1.45 2006 0 1.45

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Lightning Performance Research on Mexican High Voltage Transmission Lines

SOME FURTHER RESEARCH •  Update for a distribution stroke leader approach

angle. •  Development of stroke current distributions for the

first and subsequent positive and negative strokes respectively.

•  Studies on multicircuit flashovers and coupling effects for more than two groundwires on transmission lines.

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Lightning Performance Research on Mexican High Voltage Transmission Lines

•  Fast transient rise times should be considered, to determine their influence on the tower top potential at various grounding resistance values as well as tower surge impedance values.

Ø  Neural networks and fuzzy logic can be used, for the location of surge arresters on transmission and distribution lines, in order to improve the reliability line with poor lightning [14]

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1] The installation of surge arresters, improvement of footing resistance and an adequate shielding angle transmission lines have permitted obtaining good results in their lightning performance.

2] Surge arresters were mainly installed in

structures located in critical areas selected according to tripout historical information.

CONCLUSIONS

Lightning Performance Research on Mexican High Voltage Transmission Lines

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3] Good results have encouraged CFE, to continue installing surge arrester on the most critical transmission lines to improve their lightning performance.

Lightning Performance Research on Mexican High Voltage Transmission Lines

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Lightning Performance Research on Mexican High Voltage Transmission Lines

REFERENCES 1] Failures, Statistics and Relevant Works on Transmission Lines, Coordinación de Transmisión,

Gerencia de Líneas de Transmisión, CFE, 2013 (in Spanish).

2] Failures, Statistics and Relevant Works on Transmission Lines, Coordinación de Transmisión, Gerencia de Líneas de Transmisión, CFE, 2014, (in Spanish).

3] Tower Catalogue: 400 kV, 230 kV and 115 kV, CFE, 2002. (In Spanish)

4] Anderson J. G. "Monte Carlo Computer Calculation of Transmission-Line Lightning Performance". AIEE Trans. Vol. 80, pp. 414-420, August 1961.

5] GUIDE TO PROCEDURES FOR ESTIMATING THE LIGHTNING PERFORMANCE OF TRANSMISSION LINES. Working Group 01 (Lightning) of CIGRE Study Committee 33 (Overvoltages and Insulation Coordination). October 1991.

6] Whitehead E. R. LIGHTNING. Lightning Protection, Vol. 2, Chapter 22. Protection of Transmission Lines. Academic Press, 1977, (Book Edited by R. H. Golde), ISBN 0 12 287 802 7

Lightning Performance Research on Mexican High Voltage Transmission Lines

7] Bewley L. V. Travelling Waves on Transmission Systems. 2nd Edition, John Wiley

& Sons, Inc. N. Y., 1951, Book.

8] R o m u a l d o Torres C.

Lightning Outages Calculations for Transmission Lines .Eleventh International Symposium on High - Voltage Engineering. Conference Publication No. 467. Vol. 2. Topic C. Lightning, protection against strikes, earthing. London, U. K. The Institution of Electrical Engineers. 23-27 August, 1999.

9] R O M U A L D O TORRES C.

Lightning Performance of Transmission and Distribution Lines. PhD Thesis, University of Manchester Institute of Science and Technology, Manchester, Inglaterra, 1996.

10] Furukawa S., U s u d a O . Isozaki T., Irie T.,

Development and Application of Lightning Arresters for Transmission Lines. IEEE PWD, Vol. 4, No. 4, pp. 2121-2129, October 1989.

11] Romualdo T. C., Fonseca M. F.

Field experience on the application of surge arresters on transmission lines. IEEE 2010 Transmission and Distribution Conference and Exposition. April 19-22, 2010. New Orleans, Louisiana.

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Lightning Performance Research on Mexican High Voltage Transmission Lines

12] Romualdo Torres C . , C a m p o s Miramontes A.

Lightning protection of 230 kV Transmission Lines with Surge Arresters. ALTAE 2007, Paper Number 60, Cuernavaca, Mor. México. (In Spanish).

13] Lightning Field Performance of 230 and 400 kV Transmission Lines and the Application of Alternative Protecting Methods, IIE, Internal project report 13704, November 2009, (in Spanish).

14] Romualdo T. C., Ramírez G. M., Escamilla P. A.

Lightning Outage Transmission Line Reliability Improvement with Surge Arresters. 2016 TRANSMISSION AND DISTRIBUTION CONFERENCE AND EXPOSITION Submitted for publication.

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Contact:

Carlos ROMUALDO TORRES, PhD (Eng)

Tel: + 52 777 3623811 ext 7268

crt@iie.org.mx

Lightning Performance Research on Mexican High Voltage Transmission Lines