Farhad Rachidi-Haeri

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In this paper, three machine learning (ML)-based approaches—XGBoost, Artificial Neural Network (ANN), and Random Forest algorithms—are compared for the localization of lightning through the analysis of lightninginduced voltages on power transmission lines. ...

This paper presents a comprehensive study on the effect of the frequency dependence of soil electrical parameters on the lightning radiated electromagnetic fields as well as their associated induced voltages on overhead lines. To this aim, a fullwave appro ...

As sampling is taking place, the most active regions of the spectrum can be identified (i.e. the vicinity of spectral peaks). By selectively increasing the spectral density within those regions improves the quality of the total spectral representation redu ...

This study examines the relationship between upward negative stepped leader pulses in upward positive lightning and preliminary breakdown pulses (PBPs) in downward negative lightning discharges. Through analysis of simultaneous channel-base current and electric field data from the Säntis tower in Switzerland, we found notable similarities between Category A and B upward positive lightning pulses and the “Classical” and “Narrow” PBPs observed in downward negative flashes. Statistical comparisons reveal corre

Factors that contribute to lightning-caused faults on the line insulation of overhead distribution lines and suggested improvements to existing and new constructions are identified in this guide. ...

This paper summarizes the main findings of a long-term research to explore the use of high power electromagnetics in humanitarian demining. A neutralization method based on remote detonation of electrically-activated improvised explosive devices (IED) was ...

This paper introduces the results obtained so far using electromagnetic time reversal (EMTR) to locate partial discharges (PDs) in power systems, aiming to improve their reliability. PD events, occurring inside insulator defects, can lead to faults or supply interruptions. Accurate PD localisation methods are crucial tools for protecting power systems and improving their resilience. In EMTR-based PD localisation [1], the measured PD signals are time-reversed and re-emitted back into the system model. During

The authors present an analysis in the frequency domain of lightning electromagnetic fields making use of a computer code developed by the authors. The analysis is made for different distances from the lightning channel, for two different current waveshapes corresponding to the first and the subsequent negative return stroke, and evidencing the contribution of the various terms (static, induction and radiation) to the total field. The calculated frequency spectra match satisfactorily with the average spectr

In this paper, a model to analyze the propagation of intentional electromagnetic interferences disturbances along penetrating conductors into concrete walls is proposed. The model is based on the transmission line theory and considers the attenuation of th ...

Lightning discharges between charged clouds and the Earth’s surface are responsible for considerable damages and casualties. It is therefore important to develop better protection methods in addition to the traditional Franklin rod. Here we present the fir ...

This paper presents experimental results on the transient response of a buried insulated wire subjected to fast transient signals. It reports measurements of voltage and current at the sending end, as well as the voltage at the receiving end of the insulat ...

Controlling lightning is a long-time dream of mankind. Along with the rapid evolution of laser technologies, the idea to develop lightning protection based on filamentation of high-power ultrashort-pulse lasers emerged in the 1990s [1]. The goal of the Las ...

An effective method based on the regularization technique to solve the problem of the high-frequency electromagnetic field coupling to an overhead transmission line is presented. The integral-differential equation describing the field-induced current into ...

The paper addresses the important issue of evaluating the overvoltages produced on a power system by a lightning event. First, the theoretical formulation of the problem in the time domain is presented. Then its numerical solution together with its impleme ...

The conversion between the common and the differential modes is of great importance in the transmission of data over poorly balanced cables such as electrical wiring. In this paper, we have studied some of the mechanisms involved in this conversion, both e ...

In this paper, we present a stable method for simulating passive distributed networks connected to linear and nonlinear devices using the time marching (TM) method. The method is based on the use of the Z-transform for analyzing and obtaining the TM equati ...

We present an analysis of the response of a grounding electrode located on the top of a mountain. Specifically, we derive an analytical solution for the low-frequency response of a hemispheric grounding electrode buried on the top of a cone-shaped mountain ...

In this paper, the electromagnetic susceptibility of electro-explosive devices (EEDs) including their connection wires is assessed statistically. The electromagnetic coupling and the thermal power dissipation are modeled to determine the activation conditi ...

Dealing with lightning performance computation, researchers usually consider only negative downward first return strokes and the relevant channel-base peak current distribution. The aim of this article is to account for the lightning flash mechanism, which ...

The amount of charge transferred to ground during long continuing currents in natural downward flashes can be obtained either through direct current measurements or using remote electromagnetic fields, if direct measurements are not feasible. In this study ...

Farhad Rachidi-Haeri

Chattez avec Graph Search

An Efficient Machine Learning Model for Lightning Localization via Lightning-Induced Voltages on Transmission Lines

Evaluation of Lightning Electromagnetic Fields and Their Induced Voltages on Overhead Lines Considering the Frequency Dependence of Soil Electrical Parameters

Inclusion of an automatic adaptive sampling method in NEC

Similarities in the Initiation of Upward Positive and Downward Negative Lightning Flashes

IEEE Guide for Improving the Lightning Performance of Electric Power Overhead Distribution Lines

High Power Electromagnetics Applied to Humanitarian Demining in Colombia

Electromagnetic Time Reversal for Power System Reliability

Frequency analysis of lightning stroke electromagnetic fields

Study of the Propagation of Common Mode IEMI Signals Through Concrete Walls

Laser-guided lightning

High-frequency transients in buried insulated wires: Transmission line simulations and experimental validation

Laser-guided lightning using kHz filamentation at 1030 nm

An Effective Approach for High-Frequency Electromagnetic Field-to-Line Coupling Analysis Based on Regularization Techniques

Evaluation of Power System Lightning Performance, Part I: Model and Numerical Solution Using the PSCAD-EMTDC Platform

On the mechanisms of differential-mode to common-mode conversion in the broadband over power line (BPL) frequency band

Stable Simulation of Multiport Passive Distributed Networks Using Time Marching Method

Calculation of the Grounding Resistance of Structures Located on Elevated Terrain

Susceptibility of Electro-Explosive Devices to Microwave Interference

Estimation of the Lightning Performance of Overhead Lines Accounting for Different Types of Strokes and Multiple Strike Points

Estimation of Charge Transfer During Long Continuing Currents in Natural Downward Flashes Using Single‐Station E‐Field Measurements