Farhad Rachidi-Haeri

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This paper investigates the effect of frequency-dependent soil parameters on the simulation of electromagnetic transients on overhead lines, based on the application of the FDTD method to solve the telegrapher’s equations. The ground return impedance is ca ...

Currently, plenty of sensitive electronic devices are installed in secondary circuits in substations and power plants. Electronic devices may malfunction and become damaged owing to electromagnetic disturbances caused mainly by lightning surges. To protect ...

We present a theory for the EMC problem of electromagnetic field coupling to a long line with arbitrary terminations. The theory is applicable for the high-frequency plane wave electromagnetic field excitations, when the transmission line approximation is no longer valid. Analytical expressions are derived for the induced current along the line, and at the two-line terminals. The coefficients of these expressions are determined using a procedure based on the exact solutions of the integral equation for two

This paper presents an efficient modeling approach for parallel counterpoise wires used in the tower-footing grounding systems of high-voltage transmission lines. The proposed method is based on transmission line theory, with the governing equations solved ...

The aim of this paper is to present an experimental validation of a frequency- domain approach to the solution of the lightning electromagnetic field-to- buried cable coupling equations. The coupling to the inner conductor is evaluated using the concept of ...

The imaging of electromagnetic interference sources in devices is an interesting tool for electromagnetic compatibility pre-compliance testing, but it poses three significant challenges: i) the sources size is often subwavelength, meaning that the diffraction limit hinders their imaging, and the ii) spatial and iii) temporal features of the sources are uncontrolled. Indeed, in space, their spurious propagation occurs in devices with arbitrary shapes and materials; and in time, they occur either because of u

The basic information for designers of lightning protection of MV and LV networks is given in Part I of the present publication. This Part II gives an application of this basic information to the lightning protection of MV networks containing overhead lines. As the overvoltages due to lightning reach important values, an economical and safe network design calls for extensive lightning protection. This general statement applies to high voltage as well as medium and low voltage networks. Overvoltage protectio

The Säntis Tower was instrumented in May 2010 to measure currents of lightning discharges striking the structure. Since then, the system has been recurrently updated and expanded. Presently, data associated with lightning striking the tower are collected a ...

In this paper, lightning electromagnetic fields in the presence of an ocean-land mixed propagation path having different configurations are evaluated using a finite-element-based full-wave approach. The simulations are conducted considering lightning strik ...

Compares five lightning return stroke current models that exhibit a simple relationship between the current at the return stroke channel-base and the current along the return stroke channel, namely the Bruce-Golde (BG) model, the transmission line (TL) model, the Master, Uman, Lin, and Standler (MULS) model, the Traveling Current Source (TCS) model, and the Modified Transmission Line (MTL) model, by assuming a common current wave shape at the channel base and then calculating the channel currents and charge

In online single-sided partial discharge (PD) location, the measured PD reflection patterns are affected by the characteristics of all the components of the associated power network. This paper analyses the performance of a PD location method based on elec ...

This article presents for the first time an OpenACC (Open accelerators)-aided Graphics Processing Unit (GPU)-based approach adopting a 3D moving window finite difference time domain (MW-FDTD) method for calculating lightning electromagnetic fields over lar ...

The localization of partial discharge (PD) sources is of importance for the monitoring and maintenance of power transformers. Time difference of arrival (TDoA) based methods are widely adopted in the literature for the localization of PDs. Recently, time r ...

This paper reports the results of two experimental campaigns aimed at studying the high-frequency response of a raceway containing low voltage power, telephone, and Ethernet cables, to external electromagnetic field illumination. The raceway was tested aga ...

Benford's law applies to a wide variety of natural and man-made datasets and it has been successfully applied to test the integrity of data and to detect possible fraud and anomalous results in economy, politics, and management studies. In this paper, we i ...

Time reversal is an established wave imaging and focusing method that has proved to be robust and compatible with super-resolution imaging and focusing, i.e., to provide images and foci with subwavelength features beyond the diffraction limit. The method has been applied to numerous wave systems. We propose a systematic review of super-resolution time reversal applied to electromagnetic waves in the radio-frequency regime. We examine the theoretical foundation, the methods and the applications of radio-freq

In this paper, we present an efficient measurement technique for the analysis of power line communication (PLC) signals. The frequency spectrum associated with PLC signals extends from 1 MHz to 30 MHz. The proposed technique can be applied to a network containing multiconductor overhead lines and/or underground cables and it complements the theoretical formalism based on scattering parameters presented previously in the work of F. Issa et al. (2002). The use of a vector network analyzer is recommended for t

This paper presents a new approach to model a transmission tower for lightning performance studies. It consists of representing each part of the tower by equivalent vertical and/or horizontal transmission lines as required. While horizontal line parameters are obtained from standard line formulas, specific expressions are derived for the parameters of vertical lines. Moreover, mutual coupling between any two parallel vertical transmission lines is taken into account. Transient waveforms obtained using the p

In this article, we propose a novel approach for the localization of electromagnetic interference (EMI) sources based on the concept of compressive sensing and metalenses. We show that using the spatial and frequency dispersion offered by the metalens, we ...

This paper presents a brief theoretical discussion on the issue of the wire-grid representation of surfaces using the Numerical Electromagnetics Code (NEC). Different approaches for the determination of the parameters (in particular, the segment radii) of ...

Farhad Rachidi-Haeri

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Simulation of High-Frequency Transients in Overhead Lines Including Frequency-Dependent Soil Parameters: an FDTD Aproach

Three-Dimensional FDTD-Based Simulation of Induced Surges in Secondary Circuits Owing to Primary-Circuit Surges in Substations

High-frequency electromagnetic field coupling to long terminated lines

Efficient modeling of parallel counterpoise wires using an FDTD-based transmission line approach

Lightning-induced currents in buried coaxial cables: A frequency-domain approach and its validation using rocket-triggered lightning

Space- and time-agnostic imaging of subwavelength electromagnetic sources

Lightning protection of distribution networks. Part II: Application to MV networks

Säntis lightning research facility: a summary of the first ten years and future outlook

The Influence of the Slope Angle of the Ocean–Land Mixed Propagation Path on the Lightning Electromagnetic Fields

Lightning return stroke current models with specified channel-base current: a review and comparison

Electromagnetic time reversal for online partial discharge location in power cables: Influence of interfering reflections from grid components

Assessing the Efficacy of a GPU-Based MW-FDTD Method for Calculating Lightning Electromagnetic Fields Over Large-Scale Terrains

An experimental validation of partial discharge localization using electromagnetic time reversal

Experimental Characterization of the Response of an Electrical and Communication Raceway to IEMI

Benford's Law and Its Application to Lightning Data

Radio-frequency Subwavelength Time-reversal Imaging and Focusing: A Review of Theory, Methods, and Applications

Analysis of power line communication networks using a new approach based on an efficient measurement technique

Nonuniform transmission tower model for lightning transient studies

A Compressive Sensing Framework for EMI Source Localization Using a Metalens Structure: Localization Beyond the Diffraction Limit

On the use of the equal area rule for the wire-grid representation of metallic surfaces