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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.

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Projektowanie i aplikacja konstrukcji wyłącznika zwarciowego do rozdzielnicy wysokiego napięcia w izolacji gazowej

Staszak S.

Wiadomości Elektrotechniczne

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2013

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R. 81, nr 5

15-17

PL

Przedstawiono wyniki prób i testów wyłącznika EB-01 zainstalowanego w rozdzielnicy gazowej OPTIMA 145.

EN

The paper presents results of tests of EB-01 circuit breaker installed in gas insulated OPTIMA 145 switchgear.

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Pattern recognition for partial discharge in GIS based on pulse coupled neural networks and wavelet packet decomposition

Zhou J., Tang J., Zhang X., Tao J.

Przegląd Elektrotechniczny

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2012

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R. 88, nr 5b

44-47

EN

Based on the characteristics of partial discharge (PD) defects in gas insulated switchgear (GIS), four typical single defects were designed for the present paper. PD three-dimensional (3D) patterns were constructed based on the ultra high frequency detection systems. The pulse-coupled neural networks (PCNN) and wavelet packet decomposition (WPD) method were used in PD feature extraction. The recognition results show that the proposed method used in PD feature extraction can effectively improve the accuracy of pattern recognition rate.

PL

Przeanalizowano defekty wyłącznika gazowego z wyładowaniem niezupełnym. Defekty te przedstawiane są jako obrazy 3D. Do ekstrakcji cech tych obrazów wykorzystuje się transformatę falkową i impulsowo sprzężone sieci neuronowe.

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Application of Gustafson-Kessel clustering algorithm in the pattern recognition for GIS

Wang H., Huang C., Yao L., Qian Y., Jiang X.

Przegląd Elektrotechniczny

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2011

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R. 87, nr 1

215-219

EN

This paper simulates four typical defects in GIS for PD detection, and uses the pulse, amplitude, phase and number of PD to form the three-dimensional PQN matrix. Based on the PQN, three two-dimensional distributions of Hqmax~Phi, Hqmean~Phi and Hn~Phi can be achieved. Then the new G-K clustering method is introduced to separate the four different defects according to the parameters of Sk, Ku, Pe, Q and CC. At last the comparison with different clustering methods is achieved based on the evaluation criterions which are PC, CE, PI and SI.

PL

W artykule zasymulowano cztery typowe defekty w łącznikach gazowych wynikające z wyładowań niezupełnych oraz wykorzystano amplitudę, fazę i liczbę impulsów do sformowania trzywymiarowej macierzy PQN. Następnie wykorzystano nową metodę klastrową do rozdzielenia różnych defektów na podstawie parametrów Sk, Ku, Pe,Q i CC. Następnie przeprowadzono porównanie różnych metod.