DETERMINATION OF THE SOIL SOUNDING DEPTH FOR THE EARTHING RESISTANCE CALCULATION OF SUBSTATIONS 35 KV
Keywords:earthing arrangement, earthing resistance, the soil sounding, Wenner installation, electromagnetic diagnostics
AbstractPurpose. Determination of the minimum required sounding depth for calculation of the earthing resistance for substations with a voltage class of 35 kV. Methodology. For each ratio of electrical resistivity values of soil layers, earthing resistance was calculated with changing of the layers separation depth from 0.4 m to hmax, where hmax is the layers separation depth in a two-layer soil at which the earthing resistance value becomes the same as in a uniform soil. Results. In the experiments carried out, a family of curves was obtained that describes the effect of separation depth of soil layers for various combinations of soil electrical resistivities and geometric dimensions of the earthing arrangement. The accumulated statistical data for substations with a voltage class of 35 kV made it possible to determine the required sounding depth depending on the maximum size of the earthing arrangement and the probability of the relative resistivity falling into the corresponding range of values. An algorithm is proposed for determining the required investigation depth by Wenner method as part of the electromagnetic diagnostics of the earthing arrangement of existing substations with a voltage class of 35 kV. Originality. For the first time, a probabilistic relationship was established between the ratio of the electrical resistivity of soil layers, the size of the earthing arrangement, and the necessary depth investigation of the geological medium. As a result it has been proven that there are substations for which the required sounding depth does not exceed the maximum size of the earthing arrangement. Practical value. The use of the algorithm developed in this work allows increasing the accuracy of the earthing resistance calculation of electrical installations with voltages above 1 kV operating in a network with isolated neutral.
Pravyla ulashtuvannja elektroustanovok [Electrical Installation Regulations]. Kharkiv, Fort Publ., 2017. 760 p. (Ukr).
Baranov M.I., Buriakovskyi S.G., Rudakov S.V. The tooling in Ukraineof model tests of objects of energy, aviation and space-rocket engineering on resistibility to action of pulsed current of artificial lightning. Electrical engineering & electromechanics, 2018, no.4, pp. 45-53. doi: 10.20998/2074-272X.2018.4.08.
Natsional'nyy standart Ukrayiny. SOU 31.2-21677681-19:2009. Viprobuvannya ta kontrol' prystroyiv zazemlennya elektroustanovok. Tipova іnstruktsіya [National Standard of Ukraine SOU 31.2-21677681-19:2009. Test and control devices, electrical grounding. Standard instruction]. Kyiv, Mіnenergovugіllya Ukrayiny Publ., 2010. 54 p. (Ukr).
Koliushko D.G., Rudenko S.S. Analysis of methods for monitoring of existing energy objects grounding devices state at the present stage. Electrical engineering & electromechanics, 2019, no.1, pp. 67-72. doi: 10.20998/2074-272X.2019.1.11.
Koliushko D.G., Rudenko S.S., Koliushko G.M. Analysis of electrophysical characteristics of grounds in the vicinity electrical substation of Ukraine. Electrical engineering & electromechanics, 2015, no.3, pp. 67-72. (Rus). doi: 10.20998/2074-272X.2015.3.10.
Kostruba S.I. Izmerenie elektricheskih parametrov zemli i zazemlyayushchih ustrojstv [Measurement of electrical parameters of the earth and grounding device].Moscow, Energoatomizdat Publ., 1983. 168 p. (Rus).
Koliushko G.M., Koliushko D.G., Rudenko S.S. On the problem of increasing computation accuracy for rated parameters of active electrical installation ground grids. Electrical engineering & electromechanics, 2014, no.4, pp. 65-70. (Rus). doi: 10.20998/2074-272X.2014.4.13.
Kolechitsky E.S., Medvedev V.T. Estimation of the size of the current spreading zone in the area of grounding conductors. Energetik, 2015, no.10, pp. 17-20. (Rus).
Borisov R.K., Gorshkov A.V., Zharkov Y.V. Zazemliaiushchie ustroistva elektroustanovok (trebovaniia normativnykh dokumentov, raschet, proektirovanie, konstruktsii, sooruzhenie): spravochnik [The grounding system of electrical installations (regulatory requirements, calculation, design, construction: Handbook].Moscow, Publishing House MEI, 2013. 360 p. (Rus).
How to Cite
Copyright (c) 2020 D. G. Koliushko, S. S. Rudenko, L. V. Asmolova, T. I. Tkachova
This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.
Authors who publish with this journal agree to the following terms:
1. Authors retain copyright and grant the journal right of first publication with the work simultaneously licensed under a Creative Commons Attribution License that allows others to share the work with an acknowledgement of the work's authorship and initial publication in this journal.
2. Authors are able to enter into separate, additional contractual arrangements for the non-exclusive distribution of the journal's published version of the work (e.g., post it to an institutional repository or publish it in a book), with an acknowledgement of its initial publication in this journal.
3. Authors are permitted and encouraged to post their work online (e.g., in institutional repositories or on their website) prior to and during the submission process, as it can lead to productive exchanges, as well as earlier and greater citation of published work.