Farhad Rachidi-Haeri

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The standard lightning waveforms used for the testing of aircraft are based on downward lightning. However, there is evidence suggesting that lightning to aircraft is different from negative downward lightning. Also, carbon fiber composite materials are be ...

This paper aims at proving the application of the fault location method based on the Electromagnetic Time Reversal (EMTR) to multi-terminal HVDC (MTDC) networks. In particular, the paper integrates the EMTR fault location technique with the protection sche ...

The computation of lightning-originated surges on overhead power lines due to nearby lightning return strokes requires accurate models for the calculation of both the incident lightning electromagnetic pulse (LEMP) and the coupling of this field with the l ...

The voltages induced by nearby lightning strikes are a major cause of outages in power distribution systems. We compute such voltages taking into account the effects of the dart leaders that precede subsequent return strokes in both natural and rocket-triggered discharges. The results show that for stroke locations that are approximately alone, the line prolongation, the leader electric field change has a significant influence on the amplitude and shape of the induced voltages. The taking into account of th

The amplitude-enhancement effect of ground resistivity and corona on voltages induced by lightning electromagnetic fields on overhead transmission lines, earlier analyzed by the authors in previous works, is here emphasized. Various examples explaining the mechanism leading to such an enhancement are given. When available, experimental results supporting the numerical calculations are presented.

This paper presents an application of the Electro-magnetic Time Reversal (EMTR) in changing media to identify the fault location along a single-conductor transmission line. It is shown that the time-reversed quantities exhibit a property, called Mirrored M ...

We present in this paper an analysis of the electromagnetic emission associated with power line communications (PLC) systems. Using coupling factors obtained experimentally for different typical indoor configurations, we calculate radiated fields associated with signals having a magnitude given by the EN550022/CISPR22 limits. We show that the resulting fields exceed, for a wide range of frequency, some of the current emission limits such as the German NB30, the BBC, the Norway and the UK MPT 1570 proposals.

The recent development of high average, high peak power lasers has revived the effort of using lasers as a potential tool to influence natural lightning. Although impressive, the current progress in laser lightning control technology may only be the beginn ...

This paper presents a review of lightning M-component models. M-component models are classified into two main categories: (i) the guided-wave M-component model and its extensions and (ii) nonlinear M-component models. Other models and assumptions, in which ...

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 ...

The streamer bursts generated during the initiation and propagation of leaders play an important role in the creation and maintenance of hot discharge channels in air. The most important parameters related to streamer bursts in this respect are the length ...

In this paper, a series of numerical simulations are conducted for various 2D and 3D configurations to demonstrate the performance of the Time Reversal MUltiple SIgnal Classification (TR‐MUSIC) method. The results reveal the excellent performance of TR‐MUS ...

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 ...

Lightning is directly or indirectly responsible for significant human casualties and property damage worldwide. A timely prediction of its occurrence can enable authorities and the public to take necessary precautionary actions resulting in diminishing the ...

In this paper, the authors further validate a theory presented previously by themselves for evaluating currents induced by external electromagnetic fields on a finite-length horizontal wire above a perfectly conducting ground. They present an approach to generalize the developed method for more complex terminal wire configurations (other than the simple case of an open line) which requires one to take into account the interaction between wire sections with different directions. The feasibility of the propos

Dealing with realistic networks, the solution of lightning electromagnetic field coupling to transmission lines is generally obtained through a Finite-Difference Time-Domain (FDTD) algorithm interfaced with an electromagnetic simulator. As well known, the ...

According to theory, once certain conditions are fulfilled, current and voltage pulses propagate along ideal transmission lines with the speed of light. One can reach such a conclusion only when the conductors are assumed to be perfectly conducting, which ...

Lightning is highly destructive due to its high power density and unpredictable character. Directing lightning away would allow to protect sensitive sites from its direct and indirect impacts (electromagnetic perturbations). Up to now, lasers have been una ...

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

This paper presents statistical distributions of lightning current parameters based on the lightning current and current-derivative waveforms measured at the Säntis Tower site in 2010 and 2011. The total number of flashes analyzed in this study was 167, wh ...

Farhad Rachidi-Haeri

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On the adequacy of standardized lightning current waveform for composite structures for aircraft and wind turbine blades

Fault Location in Multi-Terminal HVDC Networks Based on Electromagnetic Time Reversal with Limited Time Reversal

Use of the full-wave finite element method for the numerical electromagnetic analysis of LEMP and its coupling with overhead lines

Voltages induced on overhead lines by dart leaders and subsequent return strokes in natural and rocket-triggered lightning

On the amplitude enhancement of voltages induced by external EM fields on transmission lines due to ground losses and corona phenomenon

Using Electromagnetic Time Reversal to Locate Faults in Transmission Lines: Definition and Application of the Mirrored Minimum Energy Property

Evaluation of indoor PLC radiation resulting from conducted emission limits

Physics and technology of Laser Lightning Control

A Review of the Modeling Approaches for the Lightning M-Component Mode of Charge Transfer

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

The Geometry and Charge of the Streamer Bursts Generated by Lightning Rods under the Influence of High Electric Fields

Landmine Detection Using Electromagnetic Time Reversal‐Based Methods: 2. Performance Analysis of TR‐MUSIC

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

Lightning Nowcasting Using Solely Lightning Data

Exact field-to-transmission line coupling equations for lines of finite length

A Method for the Improvement of the Stability in FDTD-Based Numerical Codes Evaluating Lightning-Induced Voltage

The Upper Bound of the Speed of Propagation of Waves along a Transmission Line

The laser lightning rod project

Säntis Lightning Research Facility Instrumentation

Statistical Distributions of Lightning Currents Associated With Upward Negative Flashes Based on the Data Collected at the Säntis Tower in 2010 and 2011