Publications de Zhaoyang Wang | EPFL Graph Search

Publications associées (29)

Electromagnetic Time Reversal: Theory, Application to Fault Location in Power Networks and Experimental Validation

The time-reversal invariance is readily described and universally embodied in most laws of nature, either in a strict or in a soft sense. Based on this underlying physical principle, time-reversal theory has been theoretically and experimentally studied in ...

EPFL2020

On Lightning Electromagnetic Field Propagation Along an Irregular Terrain

Farhad Rachidi-Haeri, Marcos Rubinstein, Mario Paolone, Davide Pavanello, Mohammad Azadifar, Zhaoyang Wang, Stefan Metz

In this paper, we present a theoretical analysis of the propagation effects of lightning electromagnetic fields over a mountainous terrain. The analysis is supported by experimental observations consisting of simultaneous records of lightning currents and ...

Institute of Electrical and Electronics Engineers2016

A Correlation-Based Electromagnetic Time Reversal Technique to Locate Indoor Transient Radiation Sources

Farhad Rachidi-Haeri, Marcos Rubinstein, Zhaoyang Wang, Qi Li

To overcome the multipath interference in locating transient electromagnetic (EM) radiation sources in an indoor environment, we propose a criterion that calculates the correlation between back-propagated signals from observation points, to be used in EM t ...

Institute of Electrical and Electronics Engineers2021

Analysis of lightning electromagnetic field propagation in mountainous terrain and its effects on ToA-based lightning location systems

Farhad Rachidi-Haeri, Marcos Rubinstein, Mohammad Azadifar, Zhaoyang Wang, Keyhan Sheshyekani

In this paper, we analyze the propagation effects on lightning-radiated electromagnetic fields over mountainous terrain by using a three-dimensional (3-D) finite difference time domain (FDTD) method. We also discuss the time delay error in the time-of-arri ...

Amer Geophysical Union2016

A Closed Time-Reversal Cavity for Electromagnetic Waves in Transmission Line Networks

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

A closed time-reversal (TR) cavity has been considered a purely theoretical concept whose experimental realization was assumed to be impossible. In this article, we demonstrate that it is, in fact, possible to realize a closed TR cavity using a network of ...

2021

A Data-Driven Fault Location Algorithm Based on the Electromagnetic Time Reversal in Mismatched Media

Mario Paolone, Zhaoyang Wang

The classical electromagnetic time reversal (EMTR) fault location method in power systems can be time consuming, especially when a high location accuracy is desired. To cope with this issue, the concept of EMTR in mismatched media has recently been introdu ...

2021

A Frequency-Domain Analysis of a Time-Reversal Cavity for Electromagnetic Waves in Transmission Line Networks

Farhad Rachidi-Haeri, Hamidreza Karami, Zhaoyang Wang, Elias Per Joachim Le Boudec

Recently, a closed time-reversal cavity for electromagnetic waves was demonstrated and experimentally realized using a network of transmission lines. This paper presents an analysis in the frequency domain of the wave propagation characteristics that perta ...

IEEE2022

Rigorous Assessment of Natural Frequencies of Fault-Originated Travelling Waves

Mario Paolone, Hamidreza Karami, Pier Luigi Dragotti, Zhaoyang Wang

This paper presents a rigorous assessment of natural frequencies associated with fault-originated travelling waves in power networks, factoring in the presence of multiple junctions and branches. The proposed assessment exploits the Baum-Liu-Tesche (BLT) e ...

2024

An Alternative Method for Locating Faults in Transmission Line Networks Based on Time Reversal

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

We present an alternative method based on the time-reversal process to locate faults in transmission line networks. The proposed procedure considers different media for the forward and the backward propagation phases. Specifically, the transverse branch re ...

Institute of Electrical and Electronics Engineers2017

Electromagnetic Time Reversal Applied to Fault Location: On the Properties of Back-Injected Signals

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

By using the electromagnetic time reversal (EMTR) theory, the paper studies its properties in order to derive a new fault location method to be used in power networks. It is shown that, in the reversed-time stage, the current signal observed at the true fa ...

Power Systems Computation Conference2018

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

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

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

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

Partial Discharge Localization Using Electromagnetic Time Reversal: A Performance Analysis

Marcos Rubinstein, Mohammad Azadifar, Hamidreza Karami, Zhaoyang Wang, Ali Ghasemi

In this study, first, a comparison on the application of electromagnetic time reversal (EMTR) and time difference of arrival (TDoA) in partial discharge localization in power transformers is presented. A two-dimensional finite-difference time-domain simula ...

2020

Properties of Direct-Time and Reversed-Time Transfer Functions to Locate Disturbances along Power Transmission Lines

Mario Paolone, Zhaoyang Wang

The paper discusses specific frequency-domain properties of the electromagnetic time reversal (EMTR) method applied to locate faults and, more in general, disturbances in power networks. Specifically, we investigate the properties of two transfer functions ...

IEEE2019

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

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

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 ...

2017

Filectromagnetic Time Reversal Applied to Fault Location: On the Properties of Back-Injected Signals

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

By using the electromagnetic time reversal (EMTR) theory, the paper studies its properties in order to derive a new fault location method to be used in power networks. It is shown that, in the reversed-time stage, the current signal observed at the true fa ...

IEEE2018

A review of time reversal-based methods applied to fault location in power networks

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

Electromagnetic time reversal (EMTR)-based methods have been applied to the problem of fault location in power networks since 2012. Over the past decade, considerable theoretical investigations have led to a continuous improvement of the EMTR method in ter ...

2023

An experimental proof of concept of time‐reversal single‐sensor acoustic source localisation: Application to partial discharges

Parsa Khorasani, Farhad Rachidi-Haeri, Marcos Rubinstein, Hamidreza Karami, Zhaoyang Wang

In this paper, for the first time, an experimental proof of concept for utilising time reversal (TR) in the acoustic regime to localise partial discharge (PD) sources was presented using a single sensor. To achieve this, an experimental setup comprising a ...

Institution of Engineering and Technology (IET)2025

Electromagnetic Time Reversal Similarity Characteristics and its Application to Locating Faults in Power Networks

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

The existing Electromagnetic Time Reversal (EMTR)-based fault location methods generally leverage the features of the signals simulated in the EMTR reversed-time stage (relative to the direct-time stage wherein a fault occurs and its originated transient s ...

2020

Locating Lightning Using Electromagnetic Time Reversal: Application of the Minimum Entropy Criterion

Marcos Rubinstein, Mohammad Azadifar, Amirhossein Mostajabi, Hamidreza Karami, Zhaoyang Wang

2019