Antonio Pierno

A New Tool for Calculation of Lightning-Induced Voltages in Power Systems—Part I: Development of Circuit Model

In this paper, we present a new tool for lightning-induced voltage calculations. The tool, a circuit model which can be integrated into power systems simulators, is based on the theory developed by Andreotti (2001, 2009, 2013). In Part II, the accuracy, stability, and efficiency of the new tool are demonstrated via comparison with other solutions/codes found in the literature and with experimental data.

Analytical Formulations for Lightning-Induced Voltage Calculations

Recently, Andreotti (2009) have presented an analytical solution for the evaluation of voltages induced on an infinitely long, lossless, single-conductor located at a given height above an infinite-conductivity ground plane, and excited by an external field due to a step current wave moving without attenuation and at a constant speed along a vertical lightning channel. The solution presented, in contrast to previously published solutions, was derived in an exact way, i.e., no approximations were introduced in its derivation. In this paper, this exact approach is extended to more practical line configurations. Specifically, still for the case of an external field due to a step current and perfectly conducting ground, the cases of terminated single-conductor line and multiconductor line (including grounded conductors) will be studied. Further, single- and multiconductor lines (including grounded conductors) excited by an external field due to a linearly rising current will be examined.

An Analytical Approach to Calculation of Lightning Induced Voltages on Overhead Lines in Case of Lossy Ground—Part I: Model Development

Andreotti (2009, 2013) have presented analytical solutions for the evaluation of voltages induced on lossless, single-, and multi-conductor lines for the case of infinite-conductivity ground and both step and linearly rising currents moving without attenuation and at a constant speed along a vertical lightning channel. These solutions were derived in an exact way (i.e., no approximations were introduced in their derivation). In this paper (Part I), the previous work is extended to the case of lossy ground. In the companion paper (Part II), the results obtained using this new formulation are compared with those given by other formulas/solutions found in the literature.

A New Tool for Calculation of Lightning-Induced Voltages in Power Systems—Part II: Validation Study

In the companion paper (Part I), a new tool for lightning-induced voltage calculations, called CiLIV, has been presented. In this paper (Part II), predictions made with the new tool are compared to experimental data and to outputs of analytical procedures/numerical codes found in the literature.

An Analytical Approach to Calculation of Lightning Induced Voltages on Overhead Lines in Case of Lossy Ground—Part II: Comparison With Other Models

In the companion paper (Part I), an analytical approach for calculating lightning-induced voltages for the case of lossy ground has been developed. In this paper (Part II), predictions of the new formulation are compared to those based on other approaches found in the literature.

Lightning-Induced Voltages on Complex Power Systems by Using CiLIV: The Effects of Channel Tortuosity

Recently, Andreotti et al. (2015) have presented a new tool for lightning induced voltage calculations on power networks. This tool, named Circuit for Lightning Induced Voltage (CiLIV), has been initially developed for straight and vertical lightning channels; afterwards, the tool has been extended to evaluate induced voltages produced by tortuous lightning channels. However, in the aforementioned studies, only simple power network configurations have been examined. Therefore, aim of this paper is twofold: 1) to apply CiLIV to more complex network configurations, that is, complex networks equipped with transformers, surge arresters, groundings, and so on; 2) to investigate the effects of channel tortuosity on the voltages induced in these complex networks.

On the Effects of Channel Tortuosity in Lightning-Induced Voltages Assessment

We present a study on lightning-induced voltages on overhead lines produced by tortuous lightning channels, by using a recently developed tool called CiLIV (Andreotti et al. 2015). CiLIV, initially developed for straight and vertical channels, is here extended to account for tortuosity. High-resolution stereoscopic images of six triggered lightning channels have been 3-D digitized and used as input data for CiLIV. The result is that tortuosity, usually ignored in lightning-induced voltage assessment, can instead play a significant role: an attempt is made in characterizing and quantifying these effects. It is shown that, in contrast to other lightning parameters, like channel-base peak current, which are log-normally distributed and generate log-normally distributed induced voltages too, tortuosity generates normally distributed induced voltages. It is also shown that these voltages can deviate up to 23% (relative standard deviation) from the mean value.

A new tool for lightning induced voltage calculations: CiLIV

We present CiLIV (Circuit for Lightning Induced Voltage), a new tool for lightning induced voltage calculations. The tool can be integrated into power systems simulators, and is based on the theory proposed by Andreotti et al. (2001, 2009, 2013). The accuracy, stability and efficiency of the new tool has been demonstrated by comparison with other solutions/codes found in the literature and with experimental data.

Correction to "An analytical approach to calculation of lightning induced voltages on overhead lines in case of lossy ground - Part I: Model development" [Apr 13 1213-1223]

The above-named article [ibid., vol. 28, no. 2, pp. 1213-1223, Apr. 2013] had an incorrect equation (11b). It is shown in the correct form here, using the same equation number as in the paper. All of the results in the article were obtained by using the correct equation and, therefore, are not affected.