Over the years, the combustion engine has represented the main focus of the automotive industry, but in the last decade the drive towards more environmentally sustainable choices has prompted the automotive world to look for alternatives. One of these is the electric one, which is gradually placing itself at the center of the business strategy of many companies, both present and future.
An opportunity for growth in a sector that has experienced an accelerated development, also for the students of Formula SAE, who exploit the competition not only as an opportunity to try their hand at something different from the classic theoretical studies, but also as a chance to increase one’s technical skills directly in the field together with many colleagues.
We talked about this with Yassin, Team Leader of the “UniUd E-Racing Team” of the University of Udine, at his first participation in the event with a project that started from a blank sheet. The push for the creation of a team that would represent the University of Friuli came directly from the students, who set out in search of a faculty advisor who could support them in the initiative, as well as opportunities that would allow them to put together a budget to an electric car, which has higher design and construction costs than an internal combustion car.
UniUd E-Racing Team students prepare the car before taking to the track.
Photo by: David Cavazza
The choice fell on electric with an eye to the future and it is precisely from the world of green energy that one of the sponsors who supported the program, Tesla, comes. The students of the University of Udine were in fact awarded by the US company at the end of a tender aimed at all the teams participating in Formula SAE: the team thus received six hundred lithium cells with which they then went on to build their own pack batteries.
For the first year in the competition, having no previous data and references, the goal is above all to build and find a reliable base, especially as regards the cooling of the battery pack, the motor and the inverter, which are the heart of the car.
“It all started from us students with the search for a professor who could act as our Faculty Advisor, because they wanted us as a university to participate in this competition. We managed to find a Faculty Advisor that we think is perfect. But it was tough from the beginning, we started from scratch, none of us had been in another team or had previous experience, so we tried to put all the notions learned during the lessons on paper. On several occasions with this path we have examined some notions that otherwise we would not have had the opportunity to deepen”.
“I am very proud of my colleagues, in less than two years we have managed to build the cars and pass the tech, a goal that I consider important for us. So we took away several satisfactions. This project, beyond the machine, has allowed us to touch such a complexity that has led us to an accelerated growth path, like a knowledge incubator. On a personal level, without this project, which I consider fundamental, I would not have acquired many notions both on the hard skill side, such as design techniques. But the most important aspect is that of soft skills, such as being able to collaborate and getting fifty people to get along, making each department progress and grow synchronously without overlapping the other, managing internal conflicts. This project represents a sort of early internship, as if we had worked continuously for two years, it is very important”.
The Formula SAE Italia 2023 paddock
Photo by: Gianluca D’Alessandro
Over the years, more and more electric cars have been added, so much so that in this year’s edition it is the class with the largest number of vehicles, while the number of combustion vehicles is gradually decreasing. Why did you decide to focus on electric when you decided to give life to this new project? Do you think it could be more useful as an experience for the future also from a working point of view?
“There is a double motivation. The first is that there is an important trend in terms of ecological transition. A few weeks ago we took part in a Lamborghini meeting and they explained to us how the entire automotive world is moving towards having at least one electric series. The first reason is therefore precisely this trend towards the electric and hybrid world, so it would have been counterintuitive to start from an internal combustion engine. I think this transition also pushes competitions such as Formula SAE to invest more and more in electric cars. Designing a car takes many months, so the idea was to make something comprehensive that could take up to two or three years, despite the exponentially larger budget requirements. In fact, from a budget point of view, it would have been easier to focus on an internal combustion car, we would probably have spent 25% of what we invested for this electric project. We could have thought of a program on an internal combustion engine, but we thought about the long term. If after a couple of years that category had been downgraded, we would have had to start from scratch, because they are two completely different areas. Furthermore, advice has also arrived from other teams, and this is a wonderful aspect of Formula SAE. We were advised to take an important first step, without looking for an easy way out that would have shifted the challenge and complexity of the electrical project in a few years”.
On the car there are numerous sponsors who support you. Among these there is also a high-level brand such as Tesla. How did this collaboration come about?
“This collaboration was born through a tender managed by Tesla, in which it gave the possibility to all the Formula Student teams intending to participate in the Formula SAE competitions to apply by sending the project of their battery pack. Tesla engineers then reviewed the designs one by one, choosing the most deserving ones. For the winners of the tender, the alternatives were either the supply of the entire cells or a discount voucher to spend in suppliers of cell packs already assembled and certified by Tesla. We presented our project, which was then validated by Tesla engineers and we received a supply of six hundred lithium cells with which we then went on to build our battery pack. Furthermore, we have also received chips that are inserted into our battery management system boards, which balance the cells”.
Formula SAE Italy 2023
Photo by: David Cavazza
What tools did you have at your disposal during the development of the car? And how many tests did you complete before arriving here in Varano for this competition?
“The tests are countless. In chronological order, we really started from a blank sheet two years ago, we started making sketches together which, seeing them again now, make us reflect on the path we have taken. We jotted down ideas trying to find common guidelines within the team, so as to go in one direction, so as not to waste energy on something we would not have developed later. After that, we moved on to the CAD part, where there are numerous suppliers. We use Solidworks, which provides Formula Student students with a premium license through sponsorship, therefore totally free. Thanks to this we were able to design the entire machine digitally. Then we also have other software, such as Altium, which is also provided through sponsorship, and is the software used by Tesla engineers to design the electrical part of their cars. So we designed all the PCB layouts which we then assembled and programmed, so the whole firmware was done by us. In our university we are fortunate to have laboratories well equipped with cutting-edge technologies, and we have managed to simulate the best arrangement of the cells supplied by Tesla. We therefore created a mock-up of a battery pack segment, while in a subsequent phase we recreated a mini wind tunnel to simulate the pressure drops of the pack and decide in which direction to ventilate it or at what distance to place the various cells to maximize cooling. We have tried to recreate any important design choice, in addition to simulation verification, on the bench. An example is precisely the cooling circuit: a company made us a custom radiator and we went to validate it on the bench to verify its actual performance, so as not to encounter any hitches. On the electrical side, the guys implemented a very innovative solution using a very modern language, thanks to which it was possible to manage all the control units located in the vehicle”.
One of the great challenges of electric is that of cooling the motor and the battery pack. Often if heard in Formula E, where high temperatures not only affect performance, but also the efficiency and reliability of the battery. On Sunday you will face the endurance test, one of the most demanding of these five days. Given the high temperatures these days, how much does the heat affect your preparation and competition on the track?
“Looking at various teams, you will see completely different choices. A lot depends on how the battery pack is designed and built. We, being in the first year in this competition, have chosen to find solutions that may seem basic in certain fields, while in others, such as on the electronic side, we have tried to innovate. The goal was to have solutions that would allow us to put the car on the track and collect data to validate what we’ve done. As regards some mechanical choices, therefore, we decided not to dare, so that complications would not arise that would not allow us to collect useful data. Some of our components are oversized and this is due to the fact that, having never participated before, we did not have an effective estimate of consumption, timing and other additional aspects, so we made an estimate with some correction factors. Perhaps, therefore, our battery pack is one of those that would suffer less from the heat due to the layout. On the other hand, there are teams that have very compact battery packs, perhaps with cylindrical cells, where the issue of cooling becomes much more complex, for which forced ventilation or liquid cooling solutions are studied. We have decided to cool the battery pack with six fans from above and with air intakes behind the pilot which channel the air. This is the most critical aspect. This is why there are no aerodynamic appendages, because our guys have invested most of their efforts on cooling the battery pack, motor and inverter, which are the heart of the car. The idea was therefore to run the car first, in order to collect data and have solid foundations”.
Thanks and good luck for the next challenges to the students of UniUd E-Racing Team.
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