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3 pages, 160 KiB

Open AccessEditorial

Lightning Modeling and Its Effects on Electric Infrastructures

by Massimo Brignone and Daniele Mestriner

Appl. Sci. 2021, 11(23), 11444; https://doi.org/10.3390/app112311444 - 2 Dec 2021

Viewed by 1136

Abstract

Infrastructure security and people’s safety are the first objectives when it comes to dealing with high voltages or high currents issues [...] Full article

(This article belongs to the Special Issue Lightning Modeling and Its Effects on Electric Infrastructures)

Research

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16 pages, 9295 KiB

Open AccessArticle

Lightning Surge Analysis for Overhead Lines Considering Corona Effect

by Xiaoqing Zhang and Kejie Huang

Appl. Sci. 2021, 11(19), 8942; https://doi.org/10.3390/app11198942 - 25 Sep 2021

Cited by 2 | Viewed by 1408

Abstract

Corona discharge characteristics are measured in a corona cage. The difference is found between the q–u curves under double exponential and damped oscillation surges. The behavior of the minor loops is revealed for the q–u curves under positive and [...] Read more.

Corona discharge characteristics are measured in a corona cage. The difference is found between the q–u curves under double exponential and damped oscillation surges. The behavior of the minor loops is revealed for the q–u curves under positive and negative damped oscillation surges. An extended improvement is made on the traditional approach for modeling of the q–u curves under damped oscillation surges. The extended approach has the capability of describing the complicated trajectory feature of the minor loops. On the basis of the extended approach, an efficient method is proposed for performing lightning surge analysis of overhead lines considering the corona effect. In the proposed method, an overhead line with corona is divided into a certain number of line segments. Each segment is converted into a circuit unit consisting of a non-linear branch and a linear circuit. With these circuit units connected in sequence, a complete equivalent circuit is constructed for the overhead line with corona. The transient responses can be obtained from the solution to the equivalent circuit. Then, the calculated results are compared with the field test results on a test overhead line. Full article

(This article belongs to the Special Issue Lightning Modeling and Its Effects on Electric Infrastructures)

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12 pages, 3816 KiB

Open AccessArticle

Physical Simulation of the Spectrum of Possible Electromagnetic Effects of Upward Streamer Discharges on Model Elements of Transmission Line Monitoring Systems Using Artificial Thunderstorm Cell

by Nikolay Lysov, Alexander Temnikov, Leonid Chernensky, Alexander Orlov, Olga Belova, Tatiana Kivshar, Dmitry Kovalev and Vadim Voevodin

Appl. Sci. 2021, 11(18), 8723; https://doi.org/10.3390/app11188723 - 18 Sep 2021

Cited by 7 | Viewed by 1357

Abstract

The results of a physical simulation using negatively charged artificial thunderstorm cells to test the spectrum of possible electromagnetic effects of upward streamer discharges on the model elements of transmission line monitoring systems (sensor or antennas) are presented. Rod and elongated model elements [...] Read more.

The results of a physical simulation using negatively charged artificial thunderstorm cells to test the spectrum of possible electromagnetic effects of upward streamer discharges on the model elements of transmission line monitoring systems (sensor or antennas) are presented. Rod and elongated model elements with different electric field amplification coefficients are investigated. A generalization is made about the parameters of upward streamer current impulse and its electromagnetic effect on both kinds of model elements. A wavelet analysis of the upward streamer corona current impulse and of the signal simultaneously induced in the neighboring model element is conducted. A generalization of the spectral characteristics of the upward streamer current and of the signals induced by the electromagnetic radiation of the nearby impulse streamer corona on model elements is made. The reasons for super-high and ultra-high frequency ranges in the wavelet spectrum of the induced electromagnetic effect are discussed. The characteristic spectral ranges of the possible electromagnetic effect of upward streamer flash on the elements of transmission line monitoring systems are considered. Full article

(This article belongs to the Special Issue Lightning Modeling and Its Effects on Electric Infrastructures)

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20 pages, 1146 KiB

Open AccessArticle

Impact of Grounding Modeling on Lightning-Induced Voltages Evaluation in Distribution Lines

by Daniele Mestriner, Rodolfo Antônio Ribeiro de Moura, Renato Procopio and Marco Aurélio de Oliveira Schroeder

Appl. Sci. 2021, 11(7), 2931; https://doi.org/10.3390/app11072931 - 25 Mar 2021

Cited by 10 | Viewed by 1950

Abstract

Lightning-induced voltages are one of the main causes of shutdown in distribution lines. In this work, attention is focused on the effects of wideband modeling of electric grounding in the overvoltage calculation along insulator strings due to indirect lightning strikes. This study is [...] Read more.

Lightning-induced voltages are one of the main causes of shutdown in distribution lines. In this work, attention is focused on the effects of wideband modeling of electric grounding in the overvoltage calculation along insulator strings due to indirect lightning strikes. This study is done directly in the time-domain with the grounding being represented with an equivalent circuit accounting for its dynamics. Results show that the adoption of commonly adopted simplified grounding models, such as low-frequency resistance, may lead to an underestimation of the overvoltage. According to the results, differences in the order of 25% can be found in some studied cases. Full article

(This article belongs to the Special Issue Lightning Modeling and Its Effects on Electric Infrastructures)

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12 pages, 406 KiB

Open AccessArticle

Corona Effect Influence on the Lightning Performance of Overhead Distribution Lines

by Daniele Mestriner and Massimo Brignone

Appl. Sci. 2020, 10(14), 4902; https://doi.org/10.3390/app10144902 - 17 Jul 2020

Cited by 6 | Viewed by 2429

Abstract

Overhead distribution lines can be seriously damaged from lightning events because both direct and indirect events can cause flashovers along the line. The lightning performance of such power lines is usually computed neglecting the effect of corona discharge along the conductors: in particular, [...] Read more.

Overhead distribution lines can be seriously damaged from lightning events because both direct and indirect events can cause flashovers along the line. The lightning performance of such power lines is usually computed neglecting the effect of corona discharge along the conductors: in particular, the corona discharge determined by the indirect lightning event is taken into account only by few researchers because it can have meaningful impacts only in few cases. However, when we deal with overhead distribution lines with high Critical Flashover value (CFO) and small diameters, the corona discharge caused by indirect events has to be taken into account. This paper shows the effects of corona discharge in the lightning performance computation of overhead distribution lines. The analysis will involve different configurations in terms of line diameter and air conditions, focusing on the negative effect of corona discharge in the number of dangerous events that determine line flashovers. Full article

(This article belongs to the Special Issue Lightning Modeling and Its Effects on Electric Infrastructures)

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11 pages, 2773 KiB

Open AccessArticle

An Efficient Method for Calculating the Lightning Electromagnetic Field Over Perfectly Conducting Ground

by Xin Liu and Tianping Ge

Appl. Sci. 2020, 10(12), 4263; https://doi.org/10.3390/app10124263 - 22 Jun 2020

Cited by 5 | Viewed by 2402

Abstract

In the implementation of the Cooray–Rubinstein formula, the calculation of a lightning electromagnetic field over perfectly conducting ground accounted for most of the computation time. Commonly, evaluating the ideal lightning electromagnetic field is based on the numerical integration method. In practice, only a [...] Read more.

In the implementation of the Cooray–Rubinstein formula, the calculation of a lightning electromagnetic field over perfectly conducting ground accounted for most of the computation time. Commonly, evaluating the ideal lightning electromagnetic field is based on the numerical integration method. In practice, only a sufficiently small discretization step is essential to get an accurate result, which leads to a relatively large number of calculations and results in a lengthy computation time. Besides, the programming is relatively complicated because the propagation of the lightning current along the channel must be considered. In order to increase the efficiency and simplify the programming, an improved method is proposed in this paper. In this method, the evaluation of the ideal lightning electromagnetic field is equated with a summation of analytical formulae and a simple integral operation, so it would be more efficient and easily programmed. The validation of the proposed method is demonstrated by some simulation examples. Full article

(This article belongs to the Special Issue Lightning Modeling and Its Effects on Electric Infrastructures)

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15 pages, 4808 KiB

Open AccessArticle

On the Efficiency of OpenACC-aided GPU-Based FDTD Approach: Application to Lightning Electromagnetic Fields

by Sajad Mohammadi, Hamidreza Karami, Mohammad Azadifar and Farhad Rachidi

Appl. Sci. 2020, 10(7), 2359; https://doi.org/10.3390/app10072359 - 30 Mar 2020

Cited by 8 | Viewed by 2906

Abstract

An open accelerator (OpenACC)-aided graphics processing unit (GPU)-based finite difference time domain (FDTD) method is presented for the first time for the 3D evaluation of lightning radiated electromagnetic fields along a complex terrain with arbitrary topography. The OpenACC directive-based programming model is used [...] Read more.

An open accelerator (OpenACC)-aided graphics processing unit (GPU)-based finite difference time domain (FDTD) method is presented for the first time for the 3D evaluation of lightning radiated electromagnetic fields along a complex terrain with arbitrary topography. The OpenACC directive-based programming model is used to enhance the computational performance, and the results are compared with those obtained by using a CPU-based model. It is shown that OpenACC GPUs can provide very accurate results, and they are more than 20 times faster than CPUs. The presented results support the use of OpenACC not only in relation to lightning electromagnetics problems, but also to large-scale realistic electromagnetic compatibility (EMC) applications in which computation time efficiency is a critical factor. Full article

(This article belongs to the Special Issue Lightning Modeling and Its Effects on Electric Infrastructures)

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18 pages, 4823 KiB

Open AccessArticle

Lightning Protection Methods for Wind Turbine Blades: An Alternative Approach

by Viktor Mucsi, Ahmad Syahrir Ayub, Firdaus Muhammad-Sukki, Muhammad Zulkipli, Mohd Nabil Muhtazaruddin, Ahmad Shakir Mohd Saudi and Jorge Alfredo Ardila-Rey

Appl. Sci. 2020, 10(6), 2130; https://doi.org/10.3390/app10062130 - 20 Mar 2020

Cited by 7 | Viewed by 6414

Abstract

Lightning strikes happens in a fraction of time, where they can transfer huge amounts of charge and high currents in a single strike. The chances for a structure to be struck by lightning increases as the height increases; thus, tall structures are more [...] Read more.

Lightning strikes happens in a fraction of time, where they can transfer huge amounts of charge and high currents in a single strike. The chances for a structure to be struck by lightning increases as the height increases; thus, tall structures are more prone to lightning. Despite the existing lightning protection systems available for wind turbine blades, there are still many cases reported due to the fact of damage caused by lightning strike. Owing to that, the present work introduces a new approach for a lightning protection system for wind turbine blades where preliminary investigations were done using Analysis Systems (ANSYS) Workbench. Two models were developed: one with a conventional type down conductor system and the other with a hybrid conductor system. The recorded findings have been compared and discussed, where it was found that the hybrid conductor system may provide alternative protection from lightning for wind turbine blades. Full article

(This article belongs to the Special Issue Lightning Modeling and Its Effects on Electric Infrastructures)

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