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Parametric analysis of conductive coupling of transmission line tower grounding and pipeline in multilayer soil

Markovski Blagoja, Grcev Leonid, Gjorgievski Vladimir, Velkovski Bodan, Markovska Dimitrovska Marija

Przegląd Elektrotechniczny

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2023

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R. 99, nr 7

223-226

EN

Faults in electric power system may give rise of coating stress voltages on nearby pipelines due to mutual electromagnetic coupling. To prevent hazardous situations, accurate modelling of the electromagnetic interactions between such systems is required. In this paper, we perform parametric analysis of the effects of multilayer soil and of the effectiveness of different mitigation techniques in reducing coating stress voltages on a short pipeline section due to conductive coupling. Analyses are performed using full-wave electromagnetic model, based on the method of moments.

PL

Awarie w systemie elektroenergetycznym mogą powodować wzrost napięć naprężeniowych powłok na pobliskich rurociągach w wyniku wzajemnego sprzężenia elektromagnetycznego. Aby zapobiegać niebezpiecznym sytuacjom, wymagane jest dokładne modelowanie oddziaływań elektromagnetycznych między takimi systemami. W tym artykule przeprowadzamy analizę parametryczną wpływu wielowarstwowego gruntu i skuteczności różnych technik łagodzenia w zmniejszaniu napięć naprężeń powłoki na krótkim odcinku rurociągu z powodu sprzężenia przewodzącego. Analizy przeprowadzane są z wykorzystaniem pełnofalowego modelu elektromagnetycznego, opartego na metodzie momentów.

2

Some recent developments in inerter-based devices for vibration mitigation

Wagg David J.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2023

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Vol. 71, nr 3

art. no. e144617

EN

Reducing the effect of unwanted vibrations is an important topic in many engineering applications. In this paper we describe some recent developments in the area of passive vibration mitigation. This is based on a new device called the inerter which can be exploited in a range of different contexts. In this paper we consider two recent examples; (i) where a flywheel inerter is combined with a hysteretic damper, and (ii) in which a pivoted bar inerter is developed for a machining application. In both cases, experimental test results show that the devices can outperform existing methods.

3

The use of QLARM to estimate seismic risk in Kirghizstan at the regional and city scales

Rosset Philippe, Toliss Stavro, Wyss Max

Acta Geophysica

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2020

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Vol. 68, no. 4

979--991

EN

An analysis of seismic risk using our tool QLARM has been performed for the Batken region including the cities of Aidarken and Kadamjay, 100 km SW of Osh. The damage to residential buildings and induced casualties has been estimated for a set of seismic scenarios of typical and maximum magnitude considering the existing seismicity data. Population and building datasets have been built based on up-to-date information, and for the two cities, satellite photographs and a feld survey have been used. A preliminary soil response zonation is proposed using seismic ambient noise analyses. In the investigated region, the probability of damaging earthquakes with M >6 is judged to be low because the slip accumulation rate along individual faults is only in the range of 0.01–0.3 cm/year. The amplifcation of seismic waves by soil deposits is estimated to be low; however, the proposed zonation needs to be complemented by additional seismic measurements. The calculations indicate that the combined fatalities of Kadamjay and Aidarken in a hypothetical earthquake of magnitude between 6.0 and 6.6 are fewer than 100.

4

Integrating mitigation and adaptation in climate, water and development policies in Krakow

Dubel A.

Ekonomia i Środowisko

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2017

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nr 1

226--235

EN

In view of such a complex phenomena as climate change not sufficient outcomes emerge from concentrating separately on mitigation or adaptation efforts, but rather it is their integration in a coherent policy and the subsequently planned actions that could increase effectiveness and efficiency as well as intensify the desired results. This working hypothesis is elaborated in the paper based on the case study of the city of Krakow in the Southern Poland. The aim of the paper is to identify the synergies and trade-offs from the climate mitigation and adaptation efforts planned within the climate, water and development sectors in Krakow. The scoping study of the policies and strategic documents was performed with that respect and the state-of-the-art literature was studied to capture the latest advancements in the climate mitigation and adaptation integration studies in order to develop the research method. The applied method was validated as relevant for integration of these aspects with the focus on the cities. The results show the landscape of the planned strategic actions towards mitigation and adaptation to climate change as well as synergies and trade-offs between the two. In the discussion the results are analysed in view of the identified performed studies of this type.

5

Multi-spark modeling of very fast transient overvoltages for the purposes of developing HV and UHV gas-insulated switchgear and of conducting insulation co-ordination studies

Szewczyk M.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2017

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Vol. 65, nr 6

871--882

EN

Very fast transient overvoltages (VFTO) originate from steep voltage breakdowns in SF6 gas that are inherent to operation of any switching device of the gas-insulated switchgear (GIS) type. For power stations with voltage ratings exceeding 500 kV, the ratio between equipment rated- and withstand-voltage levels becomes relatively low, which causes the VFTO peak values to reach the component’s insulation withstand-voltage levels, thus becoming a design factor for high- and ultra-high voltage GIS. While well-established approach to VFTO analyses involves only single VFTO events (the so-called single-spark approach), there is often the need to analyze the entire VFTO generation process, for which the multi-spark approach to VFTO modeling is to be employed. The multi-spark approach allows one to evaluate the VFTO impact on the GIS disconnector design along with the impact of the VFTO on selection and dimensioning of the VFTO damping solutions. As the multi-spark approach to VFTO modeling is now being increasingly used in UHV GIS developments as well as for the insulation co-ordination studies of power stations, the present paper is motivated by the need to report on the VFTO multi-spark modeling approach and to lay a common ground for development works that are supported extensively with VFTO simulations. The paper presents physical assumptions and modeling concepts that are in use in such modeling works. Development of the multi-spark GIS disconnector model for VFTO simulations is presented, followed by an overview of examples of the model application for the GIS development works and for insulation co-ordination studies.

6

Finansowanie kosztów zapobiegania i adaptacji do zmian klimatu

Dubel A.

Ekonomia i Środowisko

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2016

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nr 3

100--110

EN

Mitigating climate change ultimately contributes to reducing the costs of adaptation. Expenditures on adaptation are diverse in terms of geographical distribution and they are usually incurred to adapt to climate change or prevent their negative effects, such as natural disasters. These expenditures must be distinguished from expenses to cover disasters’ losses. From the social justice point of view, it is important who bears the costs, who contributes to the additional costs and who benefits from climate change. The paper analyses and compares sources of financing of the costs of climate change adaptation and mitigation, to determine the share of individual actors in their performance. The conducted literature review helped in identifying the sources of financing of these costs. The possibilities of growth of adaptation financing need in the face of climate change predictions, and the ability to finance the rising costs, including new ways of financing, were also analysed.