Farhad Rachidi-Haeri

Chat with Graph Search

Ask any question about EPFL courses, lectures, exercises, research, news, etc. or try the example questions below.

DISCLAIMER: The Graph Chatbot is not programmed to provide explicit or categorical answers to your questions. Rather, it transforms your questions into API requests that are distributed across the various IT services officially administered by EPFL. Its purpose is solely to collect and recommend relevant references to content that you can explore to help you answer your questions.

Different formulations of the field-to-transmission-line coupling equations are reviewed and discussed. An equivalent formulation is derived in which the source terms (or forcing functions) are expressed in terms of the magnetic excitation field. This formulation is particularly useful for evaluating field-to-transmission-line coupling when the exciting field is determined experimentally, since only the measurement of the electric field-generally easier to measure than the electric field-is necessary

Narrow bipolar events (NBEs) are impulsive and powerful intracloud discharges. Recent observations indicate that some NBEs exhibit a slanted orientation rather than strictly vertical. This paper investigates the effect of the slanted NBEs using a newly dev ...

We derive the electric and magnetic Green's functions in homogeneous dielectric uniaxial media by casting the problem as ordinary differential equations. These Green's functions feature an apparent singularity on the medium's distinguished axis. Using rigo ...

A rigorous formula representing the counterpart of the Cooray-Rubinstein expression in the time domain has recently been derived by the authors. In this paper, the formula is particularized for the cases of a unit step and a linearly rising channel-base cu ...

Return-stroke lightning models and coupling models permit a fairly good estimation of overvoltages induced by indirect lightning strokes. However, some discrepancies that still exist between measured data and calculations stress the necessity to incorporate leader effects into the models, to improve our understanding of ground conductivity effects on the formation of the fields, and to obtain more experimental data

This study examines lightning activity from 2012 to 2023 around tall structures situated across diverse geographic settings based on data from the World Wide Lightning Location Network (WWLLN), with the aim of providing a global perspective on lightning incidence in their vicinity. Lightning stroke density was calculated within a 2 km radius of each structure and compared with that in a surrounding annular region extending from 2 to 10 km, enabling the identification of potential local enhancements in light

In this paper we analyzed the time intervals between flashes in the Santis area for three highly active storms and also for a period of 21 months. The overall distributions of inter-flash time interval are found to be very similar and reasonably represente ...

Severe weather events are responsible for hundreds of fatalities and millions of euros of damage every year on the Mediterranean basin. Lightning activity is a characteristic phenomenon of severe weather and often accompanies torrential rainfall, which, un ...

This paper describes the simulation, design, realization, and experimental test of a tapered transmission line (TL) for adapting a broad-band impulse generator to a radiating antenna, for a frequency range of 50 MHz-1 GHz. Two different taper geometries ar ...

In this letter, we present an analytical solution for the resistance of a hemispheric grounding electrode located on the top of a mountain. The mountain is modeled as a truncated cone with a finite height. Recently, a closed-form solution for the grounding ...

A method for locating one or multiple partial discharge sources in a power transformer or a Gas-Insulated Substation, whereby the partial discharges emit electromagnetic and acoustic waves, the method comprising recording a signal corresponding to the wave ...

The use of sensitive electronics in avionics and wind generation systems, as well as the introduction of lower-conductivity composite materials make it important to ensure adequate lightning testing of airplanes and wind turbines. Evidence exists suggestin ...

In this paper, we analyze the grounding resistance of a vertical grounding rod located in an elevated terrain. Tall structures such as wind turbines and mobile phone base stations are often installed in remote and hilly locations to gain more power or to f ...

We compare in this paper direct measurements obtained at the Towers on Mount San Salvatore (Switzerland) and the Gaisberg Tower (Austria). They are situated in similar topographical environments but in different lightning activity zones. Direct measurement ...

Farhad Rachidi-Haeri

Chat with Graph Search

Formulation of the field-to-transmission line coupling equations in terms of magnetic excitation field

Propagation Effects of Slanted Narrow Bipolar Events: A Rebounding‐Wave Model Study

Singular Behavior Analysis of Green’s Functions in Uniaxial Media Using Ordinary Differential Equations

Some Developments of the Cooray–Rubinstein Formula in the Time Domain

Modelling of lightning-induced voltages on overhead lines: recent developments

A Global Overview of Lightning Near Tall Structures

An Analysis of the Distribution of Inter-Flash Time Intervals in the Area of the Santis Tower

Lightning Potential Index performances in multimicrophysical cloud-resolving simulations of a back-building mesoscale convective system: The Genoa 2014 event

Design, Realization, and Experimental Test of a Coaxial Exponential Transmission Line Adaptor for a Half-Impulse Radiating Antenna

On the choice between transmission line equations and full-wave Maxwell’s equations for transient analysis of buried wires

Lightning Electromagnetic Fields and Their Induced Voltages on Overhead Lines: the Effect of a Non-flat Lossy Ground

Grounding Resistance of a Hemispheric Electrode Located on the Top of a Finite-Height, Cone-Shaped Mountain

Discussion on the influence of the time derivative of the current and the charge acceleration on the radiation fields from lightning channels

A Study of Electrical Current Distribution in Anisotropic Materials with Special Reference to Lightning Interaction with Composite Materials

Distortion of electric and magnetic fields from lightning due to close-by metallic structures

Partial discharge localization using time reversal: application to power transformers and gas-insulated substations

Are Standardized Lightning Current Waveforms Suitable for Aircraft and Wind Turbine Blades Made of Composite Materials?

On the Influence of an Elevated Terrain on the Grounding Resistance of a Vertical Rod

On the proportion of upward flashes to lightning research towers

Simultaneous Measurements of Return Stroke Current, Electric and Magnetic Fields at Three Distance Ranges Associated with Lightning Strikes to The CN Tower