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Selected requirements for lightning protection in the light of actual standards and regulations on the example of an object to be protected

Dąda Anna, Błaut Paweł, Miller Piotr

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2021

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Vol. 69, nr 4

art. no. e137548

EN

Elements of the lightning protection system (LPS) often perform additional functions in the facility. Correct and economical design of these elements is possible with the fulfillment of specific requirements, close coordination and inter-branch cooperation. The article draws attention to important aspects of LPS design and highlights the ambiguities that may arise during this process. Firstly, the history of changes in national standardization in the field of lightning protection is approximated. Secondly, the individual components of external LPS are presented. Subsequently, the normative material requirements for earthing are compiled, depending on their function (for lightning protection and protection against electric shock in MV and LV installations). The last part of the paper is devoted to the comparison of the protective angle method and the rolling sphere method. The analysis was made on the example of a simple object for which LPS class I is required. It has been shown that despite the possibility of using both methods, they may result in different solutions. Depending on the choice of method, the difference in the arrangement of the air-termination system is indicated. Examples of generally available LPS solutions are also given, taking account of various materials and assembly technologies.

2

Influence of lightning current surge shape and peak value on grounding parameters

Łukaszewski Artur, Nogal Łukasz

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2021

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Vol. 69, nr 2

art. no. e136730

EN

Groundings are necessary parts included in lightning and shock protection. In the case of a surge current, high current phenomena are observed inside the grounding. They are result of the electrical discharges around the electrode when the critical field is exceeded in a soil. An available mathematical model of grounding was used to conduct computer simulations and to evaluate the influence of current peak value on horizontal grounding parameters in two cases. In the first simulations, electrode placed in two different soils were considered. The second case was a test of the influence of current peak value on grounding electrodes of various lengths. Simulation results show that as soil resistivity increases in value, the surge impedance to static resistance ratio decreases. In the case of grounding electrodes lengths, it was confirmed that there is a need to use an operating parameter named effective grounding electrode length, because when it is exceeded, the characteristics of grounding is not significantly improved during conductance of lightning surges. The mathematical model used in the paper was verified in a comparison with laboratory tests conducted by K.S. Stiefanow and with mathematical model described by L. Grcev.

3

Calculating method of electromagnetic field parameters of single grounding electrode

Gerasimovich D., Dziaruhina A.

Przegląd Elektrotechniczny

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2010

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R. 86, nr 7

148-150

EN

In this paper the calculating method of electromagnetic field parameters of single lengthy grounding electrode of tubular cross-section at flowing of alternating current of power frequency into ground is presented. The mathematical model based on Maxwell equations is proposed.

PL

W artykule zaprezentowano metodę obliczeniową parametrów pola elektromagnetycznego pojedynczej długiej elektrody uziemiającej o przekroju rurowym przy przepływie prądu zmiennego o częstotliwości sieciowej do ziemi. Zaproponowano model matematyczny oparty na równaniach Maxwella.