emplois barbosa

Established in 2014, SuperGrid Institute is an independent private company with over 150 employees of 21 different nationalities. The institute is a key player for energy transition in France and throughout Europe, specialising in innovative high and medium voltage direct current (HVDC and MVDC) power systems. SuperGrid Institute also develops new technologies for the integration of renewable energies into the electricity networks of the future.

SuperGrid Institute has been ranked every year since 2018, reaching the podium 3 times in the INPI prize list.

Find out more by visiting our website: www.supergrid-institute.com

Introduction

The protection of electrical networks aims to limit the impact of faults that can affect these networks, such as short circuits or line breaks. Lightning is one of the most frequent causes of faults affecting the components of an electrical system, particularly overhead transmission lines (OHL) [1]. Apart from lightning, pollution or vegetation can also cause faults or disturbances. Detecting and locating these faults quickly enables the faulty element to be disconnected quickly, thus preventing the fault from spreading throughout the network.

The massive integration of renewable energies, which are connected using power electronics components, makes the operation of existing detection algorithms more difficult. New fault detection methods are therefore required to guarantee the safety of the electricity network after a fault.

Objectives

The aim of this internship is to develop a local method (without communication) for detecting lightning strikes in high-voltage AC networks (HVAC) by observing the transient voltage and current waves that appear after the fault and propagate through the network.

The approach that will be developed is based on both a physical model and a ‘black box’ model of an electrical fault. It employs a model of the propagation of current and voltage waves through the network after an event (model-based part) and uses part of the current and voltage measurements at the relay to estimate the shape of the voltage and current at the location of the event (measurement-based part).

The method that will be developed is intended to be implemented in a protection relay monitoring a transmission line. Constraints relating to the acquisition frequency and bandwidth of the current and voltage sensors available will therefore have to be taken into account.

Main research direction

This internship will benefit greatly from the results obtained by the supervising team on ultra-fast fault location in HVDC [2-4,6] and HVAC networks. The main tasks envisaged are

• Literature review of recently developed local approaches for fault location and identification [3-6].

• Simulations of lightning strikes on HVAC networks to analyse the current and voltage waveforms available at different locations in the network. Electromagnetic Transient (EMT) simulation software will be used to accurately represent the voltage and current waveforms after a fault.

• Testing the existing identification algorithm on lightning faults, and evaluating the performance obtained.

• If necessary, adapt the method to take into account these faults. Signal processing or optimisation tools may be used.

• If time allows, adapt the method to hybrid lines comprising overhead and underground sections.

• Drafting of the course report. A scientific publication is also envisaged.

Expected skills

To apply, you must be in your 2nd or 3rd year of engineering school (1st or 2nd year of master degree). You must have a sound knowledge of electrical engineering. Skills in signal processing, systems modelling and parameter estimation will be appreciated.

References

[1] S. A. De Almeida, R. Pestana, and F. P. Barbosa, “The main causes of incidents in the Portuguese transmission system - Their characterization and how they can be used for risk assessment,” in Proc. 6th International Conference on the European Energy Market, EEM, Leuven, 2009.

[2] P. Verrax, N. Alglave, A. Bertinato, M. Kieffer, and B. Raison, “Low-complexity graph-based traveling wave models for HVDC grids with hybrid transmission lines: Application to fault identification,” Electric Power Systems Research, vol. 205, 2022.

[3] P. Verrax, A. Bertinato, M. Kieffer, and B. Raison. Fast fault identification in bipolar HVDC grids: a fault parameter estimation approach. IEEE trans. Power Delivery, 37(1), pp. 258-267, 2022.

[4] P. Verrax, A. Bertinato, M. Kieffer, and B. Raison. Transient-based fault identification algorithm using parametric models for meshed HVDC grids. Electric Power Systems Research, 185, 106387, 2021.

[5] R. Razzaghi, M. Scatena, K. Sheshyekani, M. Paolone, F. Rachidi, and G. Antonini, “Locating lightning strikes and flashovers along overhead power transmission lines using electromagnetic time reversal,” Electric Power Systems Research, vol. 160, pp. 282–291, 2018.

[6] P. Verrax, M. Kieffer, L. Milhiet, and B. Raison. Combined model-driven and data-driven location of lightning strikes: Application to meshed HVDC grids. Electric Power Systems Research, 2022 (submitted).