Farhad Rachidi-Haeri

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The presence of connectors or other shield interruptions can seriously degrade the EMI protection provided by the braid of an otherwise well-shielded cable system. The paper presents a methodology to determine the internal response of a discontinuous shielded cable to an exciting electromagnetic field. The analysis is performed considering different types of discontinuities such as cable connectors, pigtail terminations, and interrupted shield. For the specific case of a cable with the shield interrupted at

We implement an electromagnetic time reversal technique (EMTR) to locate lightning return strokes. The two-dimensional finite difference time domain is employed to simulate the EMTR process in both, the forward-time and the backward-time phases. Scatterers ...

Upward lightning flashes from towers are sometimes preceded by other lightning activity in the vicinity of the tower. This observation has led to a classification of upward tower lightning into self-initiated, which are not preceded by nearby lightning act ...

In this paper, we present general considerations for the application of the multiconductor transmission-line theory for simulating shielded spacecraft harness cable assemblies. Some of the practical issues that occur in the modeling process of various comp ...

We present an analysis of the thermal response of a hot-wire electroexplosive device (EED) excited with different transient signals. First-order and second-order analytical models to calculate the thermal response of an EED are assessed taking as reference ...

The paper describes a modeling tool for the design of a new air-cored current transformer called PRiME (planar Rogowski current measurement) designed on a printed-circuit board (PCB) with the coil made of the PCB printed copper layers. The PRiME technology discussed in this paper exhibits a very original way of getting an efficient external field rejection, allowing the design of air-cored transducers with remarkable overall performances. A theoretical model of the PRiME transducer is presented. The model p

A recent study pointed out that macroscopic dark matter (macros) traversing through the Earth’s atmosphere can give rise to hot and ionized channels similar to those associated with lightning leaders. The authors of the study investigated the possibility t ...

Current from nearby rocket-triggered lightning that flowed through the soil and into an unenergized test power distribution line was studied based on experimental data acquired in 2003 at the International Center for Lightning Research and Testing in Flori ...

This study assesses the accuracy of the formulations of Carson and Sunde in modeling ground effects on overhead wires, particularly for high-frequency transients and high-resistivity soils. The results reveal that these traditional formulations tend to und ...

We propose in this paper new expressions relating lightning return stroke currents and far radiated electric and magnetic fields, taking into account the presence of an elevated strike object. The derived expressions show that the presence of an elevated strike object enhances the radiated electromagnetic field. The enhancement with respect to a return stroke initiated at ground level is expressed simply through a factor equal to (1+c/v), where v and c are the return stroke speed and the speed of light, res

An engineering model to represent positive return strokes is introduced as an extension of the Modified Transmission Line model with Linear Current Decay (MTLL). This extension is grounded in experimental data on the electric fields and currents associated ...

The authors present an analysis of different charge transfer modes during upward negative flashes. The analysis includes a total number of 94 pulses that occurred during two upward negative flashes recorded at the Säntis Tower. The pulses included 59 mixed ...

Recent research work shows that there are four procedures that can be used to calculate the electromagnetic fields from a current source. These different procedures, even though producing the same total field, give rise to field components that differ from ...

This paper presents the hardware-in-the-loop (HIL) validation of a proposed FPGA-based real-time simulator for power electronics applications. The proposed FPGA-based real-time simulation platform integrates the Modified Nodal Analysis (MNA) method, Fixed ...

In this paper we review simplified analytical expressions derived by Wait using the concept of attenuation function for the analysis of the propagation of lightning-radiated electromagnetic fields over a mixed propagation path (vertically stratified ground ...

In the determination of lightning-induced voltages on overhead power lines, ground losses play a role in both the evaluation of the lightning radiated electromagnetic fields and of the line parameters. The aim of this paper is to assess the effect of these losses through each of these two mechanisms. The authors show, in particular, that for lines whose length does not exceed a certain `critical' value, the surge propagation along the line is not appreciably affected by the ground finite conductivity, and,

This paper provides some clarification on the subject of the response of multiconductor lines to lightning-originated electromagnetic fields. Specifically, the effect of the presence of more conductors on the line response is analyzed with and without taking into account the ground losses in the surge propagation. The effect of the boundary conditions is also discussed. The presented analysis shows, in particular, that the response of a matched multiconductor lossless line differs from that of a single-cond

The localization of Electromagnetic Interference (EMI) sources is very important in Electromagnetic Compatibility applications. Recently, a novel localization technique based on the Time Reversal Cavity (TRC) concept was proposed using only one sensor. In ...

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 t ...

Farhad Rachidi-Haeri

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Electromagnetic coupling to cables with shield interruptions

Numerical and Experimental Validation of Electromagnetic Time Reversal for Geolocation of Lightning Strikes

Correlation vs. Causality in Other-Triggered Upward Lightning in Tower Flashes

Numerical Simulation of the Overall Transfer Impedance of Shielded Spacecraft Harness Cable Assemblies

On the Electromagnetic Susceptibility of Hot Wire-Based Electroexplosive Devices to RF Sources

Design of a new air-cored current transformer: analytical modeling and experimental validation

Could Macroscopic Dark Matter (Macros) Give Rise to Mini-Lightning Flashes out of a Blue Sky without Clouds?

Lightning Currents Flowing in the Soil and Entering a Test Power Distribution Line Via Its Grounding

Importance of Ground Return Parameters in Transient Analysis of Overhead Wires

On the enhancement of radiated electric and magnetic fields associated with lightning return strokes to tall structures

An Engineering Model to Represent Positive Return Strokes—An Extension of the Modified Transmission Line (MTL) Model

Characteristics of different charge transfer modes in upward flashes inferred from simultaneously measured currents and fields

On the Apparent Non-Uniqueness of the Electromagnetic Field Components of Return Strokes Revisited

Hardware-in-the-Loop Validation of an FPGA-Based Real-Time Simulator for Power Electronics Applications

Extrapolation of a Truncated Spectrum With Hilbert Transform for Obtaining Causal Impulse Responses

On the accuracy of approximate techniques for the evaluation of lightning electromagnetic fields along a mixed propagation path

Importance of losses in the determination of lightning-induced voltages on overhead lines

On the Transmission-Line Approach for the Evaluation of LEMP Coupling to Multiconductor Lines

Localization of Electromagnetic Interference Source Using a Time Reversal Cavity: Application of the Maximum Power Criterion

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