Cédric Abadie, age 29, is a research engineer and head of the partial discharges section for the Highvolt project. He is the first IRT Saint Exupéry PhD student. Greg Stone [1], a specialist in the field for 30 years, presided over his thesis defence, a guarantee of confidence for industrialists who are looking for Cedric’s expertise.

Can you tell us about your career so far?

After my baccalaureate, I tried to join the air force as a fighter pilot but my eyesight wasn’t good enough. I decided to do a DUT[2] in electrical engineering in Tarbes. That was followed by a degree in industrial systems engineering and a master’s in energy management in Poitiers, mainly on the electric plasmas used in aeronautics, a sector that has always appealed to me. In quick succession I then did an internship at Airbus on partial discharges, a commitment to a Cifre[3] thesis and then a position that was turned into a PhD thesis at IRT Saint Exupéry. It was at the very beginning of IRT. After the thesis, which I started in 2014, I was hired on a permanent contract to work on the same topic that was considered long-term. I’m now head of the partial discharges section of the Highvolt project. I am the first IRT Saint Exupéry PhD student!

Can you tell us more about your role in the Highvolt project?

I am working on the Highvolt project where the focus is on ramping up voltage in aircraft which aggravates, due to altitude, physical phenomena such as plasmas (electric arcs, partial discharges), responsible for component failures, premature ageing and degradation of electrical insulation systems.

My activity is focused on detecting partial discharges. I am analysing the influence of environmental parameters (pressure and temperature) and types of voltage, in particular PWM[7], i.e. reducing the power to manage motor speed.

WHAT IS A PLASMA?

Plasma is the fourth state of matter, the three other fundamental states being solid, liquid and gas. Plasmas are extremely common in the universe, accounting for over 99% of ordinary matter. Partial discharges are plasmas such as lightning but over short distances and with less energy. A gaseous medium does not conduct electricity. It is considered a perfect electrical insulator because it is devoid of free charged particles (electrons and positive ions). When subjected to a strong electric field, it can ionise and become a conductive fluid called plasma.

There are not many experts in the world on these topics, which is why our skills are so highly sought-after and why we’ve carried out a dozen services. We attract top specialists, a sign of confidence for manufacturers, because of our collaboration with Laplace[4], which has been recognised as the world’s leading laboratory since it demonstrated the existence of partial discharges in PWM power drivers, and thanks to our growing reputation. Greg Stone, for instance, is a specialist in the area with 30 years of experience, and chaired my PhD thesis defence. The problems we are looking at, which have been known about for decades in labs, have only been a cause of concern in the aeronautics industry for 10 or so years. And it applies to all sectors: the major electricity production and distribution companies (EDF) and the automobile industry (Renault) with the increased voltage in electric cars, not to mention rail (Alstom), aeronautics and the drive-systems industry (Leroy-Somer).

Our most substantial transfer is OVERSHOT[8], nicknamed the “clothes peg”. An online and non-intrusive sensor is responsible for the detection, backed up by digital signal processing because finding these weak signals is like looking for a needle in a haystack. In aeronautics, all the equipment has to operate without partial discharges throughout its service life to avoid premature aging. Thanks to this very economical sensor, which is capable of indicating the threshold value of the discharges, it is possible to optimise the design.

The other important future transfer with high partner expectations is AIRLIFT[9], a digital tool for helping to design equipment. It provides an order of magnitude for the threshold effect of partial discharges for a given geometry, which means we can develop the industrial design by reducing the number of tests and prototypes needed.

Can you tell us more about your role in the Highvolt project?

The OCE project has had an immediate impact on using the cloud to make massive image productions associated with deep learning to analyse images and automatically detect objects of interest (clouds, airports, aircrafts). For satellite mission planning, multi-agent techniques are making a breakthrough and are being adopted by industry. They provide an appropriate response to the need to operate the mission of large systems, such as a constellation of satellites or a heterogeneous set of interoperable systems.

Today, I’m still coming to IRT Saint Exupéry nearly half a day a week. I’m monitoring the work of the SYNAPSE project and supervised the PhD thesis of Timothée Jammot[4] , which is taking on a very promising approach: to make the link between multi-agent techniques and those of reinforcement learning.

What do you like at IRT Saint Exupéry?

What I have always liked at IRT Saint Exupéry, and which has guided my choices from my thesis onwards, is the relationship between basic research and industrial application: going on the test beds of our partners to check that our research hypotheses work and then making recommendations to them.

We meet a whole host of different profiles: people like me who come directly from the lab, and people with strong industrial experience. I learn a lot about many different subjects, and these exchanges are really rewarding.

The work environment and atmosphere are very pleasant: we have specific objectives but are also encouraged to look at more remote ideas and patent development.

Is there something you’d like to share with us?

We were three friends, all in the last year of our PhDs at Laplace. It was summer. To chill out during the writing-up phase, we had an idea that we tested among ourselves. Almost two years later, after coming out of a meeting with industrial partners, we took up the idea again by carrying out tests that caused a small fire to break out at IRT Saint Exupéry and first-rate results: a significant increase in the threshold of partial discharges using a very inexpensive method. A patent was filed and the feasibility of large-scale development is being examined with our industrial partners for installation on production lines.

PUBLICATION & RELEASES

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Partial Discharges in Motor Fed by Inverter: From Detection to Winding Configuration. C. Abadie, T. Billard and T. Lebey. In IEEE Transactions on Industry Applications, vol. 55, no. 2, pp. 1332-1341, March-April 2019.

Cité dans une norme: Partial discharge testing in aeronautic environment on magnet wire and feeder cables. T. Billard, C. Abadie and T. Lebey. In IEEE Electrical Insulation Conference (EIC), Montreal, QC, 2016, pp. 101-104.

Numerical signal processing methods for partial discharge detection in more electrical aircraft. C. Abadie, T. Billard and T. Lebey. In IEEE International Conference on Dielectrics (ICD), Montpellier, 2016, pp. 540-543.

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[1] Director business development IRIS Power (Toronto, Canada) – Biography http://news.ieee.ca/2018/Mar/mar2018_files/gs.pdf
[2] University Diploma of Technology.

[3] Industrial agreement for training through research; a PhD thesis funding mechanism that helps companies recruit young doctoral researchers.

[4] Laboratory on plasma and conversion of energy (CNRS/INP Toulouse/UT3 Paul Sabatier)

[5] Grenoble Electrical Engineering (CNRS/ Grenoble INP/Univ. Grenoble Alpes)

[6] Laboratoire Systèmes Electrotechniques et Environnement (Univ. d’Artois)

[7] Pulse Width Modulation.

[8] Non-intrusive partial discharge detection tool.

[9] Partial discharge risk evaluation software.