Publications associées à OPGW

Tower-foot grounding model for EMT programs based on transmission line theory and Marti's model

This paper proposes a tower-foot grounding system model compatible with EMT programs which might be useful for the simulation of lightning transients in overhead lines. The proposed model is based on the solution of the telegrapher's equations and the appl ...

Elsevier2023

Exact Expressions for Lightning Electromagnetic Fields: Application to the Rusck Field-To-Transmission Line Coupling Model

Farhad Rachidi-Haeri, Marcos Rubinstein

An exact analytical expression for the electric field of the return stroke as excited by a propagating step current source is derived in this paper. This expression could be advantageously used to evaluate the disturbances caused by lightning on overhead l ...

2023

AC loss and electrical resistance of the RW3 diffusion-bonded joint

Vincenzo D'Auria

For the European DEMO fusion reactor, several options of the Toroidal Field (TF) coil design were proposed. The winding of the TF coil option 1 is based on React&Wind (RW), Nb3Sn, graded conductors in order to optimize the amount of superconductor accordin ...

2023

Oracular Byzantine Reliable Broadcast

Rachid Guerraoui, Martina Camaioni, Matteo Monti, Manuel José Ribeiro Vidigueira

Byzantine Reliable Broadcast (BRB) is a fundamental distributed computing primitive, with applications ranging from notifications to asynchronous payment systems. Motivated by practical consideration, we study Client-Server Byzantine Reliable Broadcast (CS ...

Schloss Dagstuhl - Leibniz-Zentrum für Informatik2022

An Efficient Methodology for the Evaluation of the Lightning Performance of Overhead Lines

Farhad Rachidi-Haeri

This article proposes a method for the derivation of a formula that links the maximum lightning-induced-overvoltage occurring on an overhead distribution line with the variables that characterize the lightning return stroke, such as the peak current, front ...

2021

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

Farhad Rachidi-Haeri, Rafael Silva Alipio

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 ...

2021

Lightning-Induced Voltages on Overhead Distribution Lines Computed through Analytical Expressions for the Electromagnetic Fields

Farhad Rachidi-Haeri, Marcos Rubinstein

The evaluation of lightning ElectroMagnetic (EM) fields represents the most cumbersome part of the lightning-induced voltages computation process. Their evaluation is usually performed through a numerical routine or with simplified analytical expressions, ...

2021

Evaluation of Site Errors in LLS Magnetic Direction Finding Caused by Large Hills Using the 3D‐FDTD Technique

Farhad Rachidi-Haeri, Wolfgang Schulz, Hannes Kohlmann

Angle and amplitude estimation errors in magnetic direction finding, called site errors, are important sensor-specific errors in lightning location systems (LLS). They are known to be caused by nearby cables and overhead lines due to induced currents. Due ...

2021

Time reversal applied to fault location in power networks: Pilot test results and analyses

Mario Paolone, Zhaoyang Wang, Reza Razzaghi

This paper presents the results of a pilot test performed on a real medium voltage distribution network in Switzerland with the aim of assessing the performance of a fault location system relying on the Electromagnetic Time Reversal (EMTR) method. To the b ...

2020

On the Modeling of Non-Vertical Risers in the Interaction of Electromagnetic Fields With Overhead Lines

Farhad Rachidi-Haeri, Marcos Rubinstein, Jun Guo

This paper proposes a simple method to take into account non-vertical risers through an equivalent partial inductance. The proposed approach was validated considering several examples and taking as reference full-wave results obtained using a numerical ele ...

2019

Estimation of the expected annual number of flashovers in power distribution lines due to negative and positive lightning

Farhad Rachidi-Haeri, Carlo Alberto Nucci

The paper deals with the estimation of the expected annual number of flashovers in overhead power distribution lines due to indirect lightning strokes and aims at extending a procedure previously proposed by the authors, limited to negative downward events ...

Elsevier2019

On the representation of thin wires inside lossy dielectric materials for FDTD‐based LEMP simulations

Farhad Rachidi-Haeri, Marcos Rubinstein, Akiyoshi Tatematsu

The finite-difference time-domain method is one of the most widely used numerical electromagnetic computation techniques, and it has become an effective tool for analyzing electromagnetic transient phenomena in three-dimensional structures and grounding sy ...

2019

Calculation of High-Frequency Electromagnetic Field Coupling to Overhead Transmission Line Above a Lossy Ground and Terminated With a Nonlinear Load

Jun Guo

High-frequency electromagnetic fields such as those associated with electromagnetic pulse (EMP) and intentional electromagnetic interference (IEMI) can couple to overhead power lines. Since the height of the overhead power lines can be comparable or even l ...

2019

Isolated vs. Interconnected Wind Turbine Grounding Systems: Effect on the Harmonic Grounding Impedance, Ground Potential Rise and Step Voltage

Marcos Rubinstein, Antonio Sunjerga, Farhad Rachidi-Haeri, Qi Li

Wind turbines are very vulnerable to lightning strikes due to their height, sharp edges and remote locations often with high soil resistivity. In this paper we present numerical simulations of the impedance of a typical wind turbine grounding geometry. We ...

Elsevier2019

Causal Consistency and Latency Optimality: Friend or Foe? [Extended Version]

Rachid Guerraoui, Willy Zwaenepoel, Diego Didona, Junxiong Wang

Causal consistency is an attractive consistency model for geo-replicated data stores. It is provably the strongest model that tolerates network partitions. It avoids the long latencies associated with strong consistency, and, especially when using read-onl ...

2018

Causal Consistency and Latency Optimality: Friend or Foe?

Rachid Guerraoui, Willy Zwaenepoel, Diego Didona, Junxiong Wang

Causal consistency is an attractive consistency model for geo-replicated data stores. It is provably the strongest model that tolerates network partitions. It avoids the long latencies associated with strong consistency, and, especially when using read-onl ...

ASSOC COMPUTING MACHINERY2018

A Semi-Analytical Method to Evaluate Lightning-Induced Overvoltages on Overhead Lines Using the Matrix Pencil Method

Jun Guo

Lightning electromagnetic fields can couple to overhead power transmission and distribution lines, causing serious effects to the power system. Lightning electromagnetic fields that couple to overhead lines have a nonuniform distribution along the line con ...

2018

A Full-Scale Experimental Validation of Electromagnetic Time Reversal Applied to Locate Disturbances in Overhead Power Distribution Lines

Mario Paolone, Farhad Rachidi-Haeri, Marcos Rubinstein, Zhaoyang Wang, Reza Razzaghi

Electromagnetic time reversal (EMTR) has emerged as a promising technique to locate disturbances in power grids, thanks to its location accuracy and robustness against parameters uncertainties. Furthermore, in a reflective medium, like the one of a power n ...

2018

Generalized Telegrapher's Equations for Buried Curved Wires

Farhad Rachidi-Haeri, Damir Cavka

The paper deals with the calculation of transient currents and voltages along curved wire structures buried in a lossy ground using the generalized Telegrapher's equations. The influence of a lossy half space is taken into account by the simplified reflect ...

IEEE2018

Effect of Dispersive Soil on the Electromagnetic Response of Buried Wires in the UHF Range

In this paper, we analyze the effect of the soil on the induced current in a buried wire excited by an external field in the ultrahigh frequency range. We use an extended version of the Messier model, which provides the electromagnetic (EM) properties of d ...

2018