Study of the Errors of the Indirect Method of Measuring the Network Phase Isolation Parameters Relative to the Ground on the Simulation Model


Annotation:

The simulation model of a 6 kV open-cast distribution network with an isolated neutral is presented. This model was developed for studying various methods of determining the parameters of network phase isolation relative to the ground. The model was built in the MATLAB software using the Simulink package and the SimPowerSystems library. Its adequacy was verified by the single-phase-to-ground fault current. The results obtained in the process of simulation and analytical calculation had a slight discrepancy, which allows to consider the simulation model as adequate.

The analysis of the current methods for determining the insulation parameters showed that the most convenient and safe approach is based on connecting additional capacitance between one of the phases of the network and the ground. This method not only ensures safety when performing measurements, but also eliminates a decrease in the reliability of electrical distribution networks. When studying the insulation parameters in the normal operating mode, the measurements are made without removing the operating voltage. Among other things, the additional capacitance has stable parameters that do not change (in contrast to the additional active conductivity) as the measurements are performed. 

The results of studies are given related to the influence of various factors on the accuracy of measuring the active and reactive components of the total insulation resistance of the network phases relative to the ground by the indicated method. The errors of the considered method based on connecting additional capacitance between one of the phases of the network and the ground are analyzed. It is concluded that the load in the network has little effect on the accuracy of the results. At the same time, the presence of asymmetry in the network leads to a significant error. The way to eliminate this disadvantage is proposed.

References:
  1. Sidorov A.I. Theory and practice of the systematic approach to ensuring electrical safety in the open pit mining: thesis... Doctor of Technical Sciences. Chelyabinsk, 1993. 444 p. (In Russ.).
  2. Gladilin L.V., Shchutskiy V.I., Batsezhev Yu.G., Chebotaev N.I. Electrical safety in the mining industry. Moscow: Nedra, 1977. 327 p. (In Russ.).
  3. Shinkarenko G.V. Determination of the Dielectric Characteristics of Electric Equipment Insulation in the Presence of Utility-Frequency Interference Currents. Power Technology and Engineering. 2016. Vol. 50. Iss. 3. pp. 341–346. DOI: 10.1007/s10749-016-0709-4
  4. Qinghua Z., Huaibin T. Diagnosis of inhomogeneous insulation degradation in electric cables by distributed shunt conductance estimation. Control Engineering Practice. 2013. Vol. 21. Iss. 9. pp. 1195–1203. DOI: 10.1016/j.conengprac.2013.04.006
  5. Meng-yu L., Song-yi D., Tao L. Insulation status mobile monitoring for power cable based on a novel fringing electric field method. Electrical, Information Engineering and Mechatronics 2011: Proceedings of the 2011 International Conference on Electrical, Information Engineering and Mechatronics (EIEM 2011). London: Springer, 2012. pp. 987–994. DOI: 10.1007/978-1-4471-2467-2_116
  6. Zang C., Ye H., Lei H., Yin X., He J., Jiang Z., He S., Zhao X. Using ultraviolet imaging method to detect the external insulation faults of electric device. 2009 IEEE Conference on Electrical Insulation and Dielectric Phenomena. 2009. pp. 26–30. DOI: 10.1109/CEIDP.2009.5377769
  7. Sobolev V.G. Electrical insulation of the mine electrical equipment. Moscow: Nedra, 1982. 143 p. (In Russ.).
  8. Lyakhomskiy A.V., Kutepov A.G. Analysis of electro traumatism on mining enterprises. Gornyy informatsionno-analiticheskiy byulleten = Mining informational and analytical bulletin. 2018. № S7. pp. 3–9. (In Russ.).
  9. Fedorov A.A., Ristkheyn E.M. Power supply of industrial enterprises. Moscow: Energiya, 1981. 369 p. (In Russ.). 
  10. Petrov O.A., Sidorov A.I., Selnitsin A.A. Methods for measuring the capacitive currents of a single-phase- to - ground fault in electrical networks with a voltage of 6–10 kV. Chelyabinsk: ChGTU, 1990. 24 p. (In Russ.).
  11. Dyakonov V.P. MATLAB R2006/2007/2008. Simulink 5/6/7. Basics of application. 2-e izd., pererab. i dop. Moscow: Solon-Press, 2010. 801 p. (In Russ.).
  12. Kostyuchenko L.P. Simulation of rural power supply systems in the MATLAB software: textbook. Krasnoyarsk: Krasnoyarskiy gosudarstvennyy agrarnyy universitet, 2012. 215 p. (In Russ.).
  13. Lure M.S., Lure O.M., Baranov Yu.S. Simulation modeling of converter circuits: textbook. Krasnoyarsk: SibGTU, 2011. 153 p. (In Russ.).
  14. Chernykh I.V. Simulation of electrical devices in MATLAB, SimPowerSystems and Simulink. Moscow: DMK Press, 2011. 288 p. (In Russ.).
  15. GOST R 50923—96. Displays. Operator's workplace. General ergonomic requirements and environmental requirements. Measuring methods. Available at: http://docs.cntd.ru/document/1200025975 (accessed: April 27, 2020). (In Russ.).
  16. Golubev V.A., Lotov A.I., Miroshkin P.P., Kuznetsov B.P., Bariev N.V., Shadrin N.M. Guide of the open-cast power engineer. Moscow: Nedra, 1986. 420 p. (In Russ.).
  17. Sverdel I.S., Samoylovich I.S, Nosov G.N., Khomtsov V.A., Kozlovskikh A.I. Guide of the open-cast power engineer. 2-e izd., pererab. i dop. Moscow: Nedra, 1973. 495 p. (In Russ.).
  18. Sidorov A.I., Boboev Kh.D. Характеристика горнодобывающих предприятий Республики Таджикистан. Bezopasnost zhiznedeyatelnosti v tretem tysyacheletii: sb. materialov VII Mezhdunar. nauch.-prakt. konf. (Life safety in the third millennium: collection of materials of the Seventh International Scientific-Practical Conference). Chelyabinsk, 2019. pp. 166–169. (In Russ.).
DOI: 10.24000/0409-2961-2020-9-24-29
Year: 2020
Issue num: September
Keywords : electrical networks isolated neutral insulation parameters additional capacitance simulation
Authors: