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Russian Electrical Engineering

, Volume 89, Issue 1, pp 54–63 | Cite as

Overcurrent Protection from Earth Faults Based on Higher Harmonics for Compensated 6- to 10-kV Cable Networks

  • V. A. Shuin
  • V. A. Martynov
  • E. S. Shagurina
  • T. Yu. Shadrikova
Article
  • 10 Downloads

Abstract

Devices based on the method of absolute measurement of the level of higher harmonics in zerosequence currents of connections of a protected object are the most commonly used for protection from earth faults in compensated 6- to 10-kV cable networks of industrial and urban power-supply systems. However, many years of operating experience have shown that the technical refinement (the selectivity and the sensitivity) of overcurrent protection from earth faults based on the method of absolute measurement of higher harmonics is not always sufficient. One of the reasons for the low technical refinement of these protection devices is the inaccuracy in estimating the maximum and minimum possible higher harmonics levels in the earth-fault current of compensated 6- to 10-kV cable networks, which are required for the selection of the operating current settings and the sensitivity determination. The main factors influencing the maximum and minimum higher harmonics levels in the earth-fault current and their ratio were revealed on the basis of the computational experiments using the imitation models for 6- to 10-kV cable networks, the limiting values of these levels were determined, an determination of the harmonics-level instability in the fault current for cable networks with different total load compositions was given, and its interrelation with the fluctuations of the total coefficient of harmonic voltage components on 6- to 10-kV buses of network power centers was established. The conditions of applicability and the area of application of overcurrent protection from this type of failure based on the use of higher harmonics of the zero-sequence current for different objects of 6- to 10-kV compensated cable networks were determined taking into account the above estimates. Specifications for a method for selecting the operating current settings were proposed.

Keywords

6- to 10-kV cable networks compensation of the capacitive currents single-phase earth faults higher harmonics overcurrent protection from earth faults based on higher harmonics conditions of applicability and area of application 

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References

  1. 1.
    Kiskachi, V.M. and Nazarov, Yu.G., Signaling of single- phase earth faults in compensated 6–10 kV cabling networks, Tr. Vses. Nauchno-Issled. Inst. Elektroenerg., 1963, no. 16.Google Scholar
  2. 2.
    Kiskachi, V.M., Surtseva, S.E., Georshenina, N.M., et al., Earth-fault signaling devices in 6–10 kV cabling network, Elektr. Stn., 1972, no. 4.Google Scholar
  3. 3.
    Borukhman, V.A., The operation of selective earth fault protection in 6–10 kV cabling networks and their improvement, Energetik, 2000, no. 1.Google Scholar
  4. 4.
    Zhezhelenko, I.V., Vysshie garmoniki v sistemakh elektrosnabzheniya prompredpriyatii (Higher Harmonics in the Power Supply Systems of Industrial Enterprises), Moscow: Energoatomizdat, 2000.Google Scholar
  5. 5.
    Kiskachi, V.M., Selectivity of earth fault signaling using higher harmonics of residual currents, Elektrichestvo, 1967, no. 9.Google Scholar
  6. 6.
    Pravila ustroistva elektroustanovok (PUE) (Rules of the Installations of Electrical Installations), Moscow: Omega-L, 2012, 7th ed.Google Scholar
  7. 7.
    Dobryagina, O.A., Shagurina, E.S., and Shuin, V.A., Effect of transient processes in earth faults in mediumvoltage electrical installations on the functions of earthfault protection based on higher harmonics, Releinaya Zashch. Avtom., 2012, no. 2.Google Scholar
  8. 8.
    RD 153-34.0-20.527-98. Rukovodyashchie ukazaniya po raschetu tokov korotkogo zamykaniya i vyboru elektrooborudovaniya (RD 153-34.0-20.527-98. Manual for Calculation of Short-Circuit Currents and Selection of Electrical Equipment), Moscow: Enas, 2002.Google Scholar
  9. 9.
    Spravochnik po proektirovaniyu elektricheskikh setei (Handbook on Engineering of Electrical Networks), Faibisovich, D.L., Ed., Moscow: Enas, 2012.Google Scholar
  10. 10.
    Shadrikova, T.Yu., Development of complex multifunctional protection from single-phase earth faults of 6–10 kV cable networks, Cand. Sci. (Tech.) Dissertation, Ivanovo, 2016.Google Scholar
  11. 11.
    Vainshtein, V.L., Analysis of higher harmonics of the earth fault current, Prom. Energ., 1986, no. 1.Google Scholar
  12. 12.
    Kiskachi, V.M., Calculation of the minimum level of higher harmonics in single-phase earth faults in power networks with isolated and compensated neutral, Tr. Vses. Nauchno-Issled. Inst. Elektroenerg., 1966, no. 26.Google Scholar
  13. 13.
    Zhezhelenko, I.V. and Tolpygo, O.B., Sensitivity of earth fault signaling using higher harmonics in industrial power networks, Elektrichestvo, 1969, no. 10.Google Scholar
  14. 14.
    Alekseev, V.G., Current protection of ZGNP-4.2 from earth faults in the stator winding of a generator operating on bus rods, Elektr. Stn., 2006, no. 2.Google Scholar
  15. 15.
    Shuin, V.A. and Gusenkov, A.V., Zashchity ot zamykanii na zemlyu v elektricheskikh setyakh 6–10 kV (Protection against Earth Faults in 6–10 kV Electrical Networks), Moscow: Energoprogress, 2001.Google Scholar

Copyright information

© Allerton Press, Inc. 2018

Authors and Affiliations

  • V. A. Shuin
    • 1
  • V. A. Martynov
    • 1
  • E. S. Shagurina
    • 1
  • T. Yu. Shadrikova
    • 1
  1. 1.Ivanovo State Power UniversityIvanovoRussia

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