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This paper presents an approximate formula for the peak value of the lightning-induced voltages in an aerial line over high resistivity soils. In its derivation, it is considered the transmission line return stroke model (TL) and a trapezoidal current waveform. The formula is an improved version of a previously expression presented by the authors, whereas its validity range is extended from 1000 Ohms...
Conference proceedings front matter may contain various advertisements, welcome messages, committee or program information, and other miscellaneous conference information. This may in some cases also include the cover art, table of contents, copyright statements, title-page or half title-pages, blank pages, venue maps or other general information relating to the conference that was part of the original...
Calculation results of attachment probability to conductors of 220–500 kV overhead transmission lines without shielding wire depending on polarity of instantaneous voltage are presented. For overhead lines with a horizontal arrangement of conductors without shielding wire the probability that a negatively charged lightning will strike to a positively charged phase rather than to a negatively charged...
The main objective of this paper is to evaluate the maximum share of the lightning current, which flows on electric installations inside of buildings. The electrical conductors are equipotentially bonded to the external lightning protection system (LPS) at the roof level. A variety of wiring in typical buildings is analyzed using the computer code CONCEPT II. The transferred charge is the most important...
We analyzed wideband electric field waveforms of 965 compact intracloud discharges (CIDs) that were recorded by the Lightning Detection and Waveform Storage System (LDWSS) operating at the Lightning Observatory in Gainesville (LOG), Florida, during August 2016. The data were acquired for discharges that occurred within 500 km of the LOG. CIDs, which may represent a serious threat to airborne vehicles,...
This work presents a proposal to represent electrical grounding systems directly in the time domain. The advantage in using this type of representation is that voltage and current are better understood in this domain and the model can easily be inserted into conventional software such as the Alternative Transient Program (ATP) and Electromagnetic Transient Program (EMTP). The proposed method is applied...
This work compares the classification accuracy (CA) of two algorithms applied to data from the EUCLID lightning location system (lLS). As CA we call the accuracy of a LLS to correctly distinguish between cloud-to-ground (CG) and intra cloud (IC) discharges. The ground-truth data, used for this evaluation, was taken from optical and electric field data measured in various regions in Austria (2012 and...
This paper presents a mathematical approach in the utilization of the Angle Method for design and analysis of a LPS — Lightning Protection System. This approach involves: a mathematical modeling to determine the Protection Angles (this modeling does not assess the merit and the criteria which determined the curves illustrated in Fig. 1 (see section 5.2.2 from [1]); the connection existent between...
This paper presents a comparison of two statistical methodologies that can be used to derive lightning withstand parameters from high-voltage laboratory tests performed on self-restoring insulation. These methodologies are used to determine the 10%, 50%, and 90% probabilities of insulation breakdown associated with a three-phase structure used in compact distribution lines in Brazil. In the performed...
This Article presents a methodology to determine the necessity of lightning Protection System (LPS) and which protection measures are preferable depending on the priorities of the installation. The selection of the protection measure will be based on: • Economic viability: comparison between the costs associated with each protection measure and their contribution for risk reduction. • Guarantee of...
Adverse Meteorological Phenomena (AMP) have great potential to cause economic and social losses, including human lives. The Middle Tropospheric Cyclonic Vortexes (MTCV), were recently discovered and there is a lack of data on formation and connection with AMP. The general objective was the analysis of the MTCV formation and the study of connections with Thunderstorms and Mesoscale Convective Complexes...
The present study has as objective to analyze frequencies of Thunderstorm that occurred in the province of Luanda (1998 to 2015), A thermodynamic study of an intense event, to evaluate the operation of the thermodynamic method. This method was based on the vertical profiles, predicted 48 hours in advance, indices of instability and trajectories of the HYSPLIT model for forecasting. Topographic influence...
This work deals with the design of a Lightning Protection System to the rocket launcher located in the Barreira do Inferno Launch Center. For its development the technical standards ABNT NBR 5419/2015 and IEC 62305 were used as main references. The Electrogeometrical Method (Rolling Spheres) was used for the development of the project, chosen after a thorough analysis of the other methods and the...
This paper is focused on proposing and comparing the performance of different wideband models intended to represent a 10 kVA 7.967 kV/240–120 V single-phase transformer with center-tapped secondary used in rural distribution networks in Brazil. The terminal behavior of this transformer is characterized by three different modeling approaches: (i) reduced-order model, (ii) full-order admittance-based...
Lightning arresters are equipments with a fundamental role in the protection of surges in substations. Thermographic images have been used in large scale to prevent faults in these devices. This paper presents a new framework aimed to nondestructive inspection of surges and medium voltage equipments. It applies a fuzzy clustering algorithm to automatic identify fault patterns in thermographs of medium...
This paper presents a study of sensitivity of the equivalent circuit of ZnO surge arresters based on the model proposed by the IEEE. The main contribution of the proposed paper consists in some modifications in the fitting procedure of the equivalent LRC circuit of the surge arrester in order to improve the accuracy during electromagnetic transient simulations in power systems. The proposed equivalent...
The present study shows an analysis of how the atmosphere affects the thunderstorm formation in Medellin City (Colombia). To carry out this study a meteorological station located in Olaya Herrera Airport and a LINET Lightning Locating System network were used. To understand the atmosphere role, atmospheric pressure, near surface air temperature, dew point temperature and wind measurements are used...
The task of Lightning Protection Systems (LPS) is to intercept lightning strikes and to divert them safely to the ground. The separation distance which is necessary to separate the electrical installation inside of a building from the LPS is mainly determined by the magnetic coupling between the lightning current carrying down-conductor and the related installation. With the use of more than one interconnected...
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