Publications de Mohammad Azadifar

A review of the modeling approaches of the lightning M-component with special attention to their current and electric field characteristics

Marcos Rubinstein, Mohammad Azadifar, Farhad Rachidi-Haeri, Carlo Alberto Nucci, Qi Li

In this paper, we present the characteristics of current, electric fields and modeling approaches of lightning M-component mode of charge transfer. We consider both the classical M-components (occurring after return strokes) and M-component-type ICC (Initi ...

2023

Partial discharge localization in power transformers using acoustic time reversal

Marcos Rubinstein, Mohammad Azadifar, Hamidreza Karami, Florent Quentin Aviolat

The localization of partial discharges (PD) is important to monitor the conditioning of high voltage insulator materials. One of the key components in power grids is the high power transformer. Localization of PDs in these pieces of equipment can increase ...

Elsevier2022

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

Marcos Rubinstein, Mohammad Azadifar, Hamidreza Karami

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 ...

2022

Localization of Electromagnetic Interference Sources Using a Time-Reversal Cavity

Marcos Rubinstein, Mohammad Azadifar, Amirhossein Mostajabi, Hamidreza Karami

In this article, we propose and implement a novel technique to locate electromagnetic interference (EMI) sources using the concept of time-reversal (TR) cavity. We show in an intuitive manner that reflections from the surfaces of a cavity can emulate an in ...

2021

An experimental validation of partial discharge localization using electromagnetic time reversal

Marcos Rubinstein, Mohammad Azadifar, Hamidreza Karami

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 ...

2021

The laser lightning rod project

Marcos Rubinstein, Mohammad Azadifar, Antonio Sunjerga, Amirhossein Mostajabi, Jean-Pierre Wolf, Clemens Herkommer, Pierre Walch, Thomas Produit

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 ...

2021

Bidirectional Recoil Leaders in Upward Lightning Flashes Observed at the Säntis Tower

Marcos Rubinstein, Mohammad Azadifar, Antonio Sunjerga, Amirhossein Mostajabi

We report the observation of three negative upward flashes recorded by a high-speed camera at the Säntis Tower during the Summer of 2019. The camera was operating at 10,000 fps and an exposure time of 99 μs. Simultaneous measurements of the lightning curre ...

2021

An Extension of the Guided Wave M‐Component Model Taking Into Account the Presence of a Tall Strike Object

Marcos Rubinstein, Mohammad Azadifar, Qi Li, Mi Zhou

We present in this paper an extension of the guided-wave M-component model of Rakov et al. considering the presence of a vertically elevated strike object. The tall object is represented as a lossless, uniform transmission line. Expressions for the current ...

2021

Partial discharge localization using time reversal: application to power transformers and gas-insulated substations

Marcos Rubinstein, Mohammad Azadifar, Farhad Rachidi-Haeri, Amirhossein Mostajabi, Hamidreza Karami

A method for locating one or multiple partial discharge sources in a power transformer or a Gas-Insulated Substation, whereby the partial discharges emit electromagnetic and acoustic waves, the method comprising recording a signal corresponding to the wave ...

2021

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