The FIA Formula E began making history in 2014 as the world’s first racing series for electric vehicles. In the first season, held in 2014/15, the teams used standard vehicles. For the 2015/16 season, the regulations allow the teams to develop their own drive trains, which means that various technical concepts are now competing against each other. The differences lie in the electric machine, including the power electronics, transmission, rear axle, cooling system, and corresponding software. This means Formula E has become an important test bed for the development of sophisticated automobile drive technologies, which is also true for Schaeffler. As an exclusive technology partner, Schaeffler developed the drive train in conjunction with its team, ABT Schaeffler Audi Sport. This means Formula E is a valuable aspect of Schaeffler’s comprehensive involvement in motor sports and development and provides important findings for Schaeffler technologies for hybrid and all-electric vehicles. Prof. Peter Gutzmer, Deputy CEO and Chief Technology Officer at Schaeffler, explains: “Our involvement in Formula E helps us to gain a better understanding of the environment and the systems in the field of electric mobility. In this way, Schaeffler is able to further develop its position as a development partner and systems supplier at the same time”. Developing and transferring expertise Electric motor: At the heart of the new electric racing car is an electric motor, the ABT Schaeffler MGU 01. During its development, engineers focused on the best-possible efficiency and high torque as well as optimum thermal characteristics and as little weight as possible. “By focusing on an optimum design for the motor and transmission, and taking the overall system into consideration, we have developed a lightweight electric motor that includes the power electronics. In this area especially, we were able to gain important insights, which we will also be able to use in volume production”, says Dr. Simon Opel, Director Special Projects Motorsports at Schaeffler. “We have successfully found a compromise between efficiency and performance, which means we are working in datamap areas that have a high degree of efficiency”, explains Opel. Transmission: ABT and Schaeffler have also developed a high-performance transmission for the ABT-Schaeffler FE01 electric racecar. It was manufactured by racing transmission specialists Hewland according to Schaeffler specifications. The transmission is also more rigid, more compact, and lighter. And of course, it also features high-performance rolling bearings from Schaeffler. Variant with one motor and three speeds The issue of how many transmission stages represent the optimum is one that always needs to be addressed with electric drives. According to the regulations of Formula E, the teams must take part in all races with a specific number of speeds and a selected number of transmission stages that are chosen before the season. This means the teams must find one solution suitable for all racetracks before the season begins. Schaeffler has decided to use three transmission stages. This enables the use of an extremely compact and lightweight electric motor, as well as offering a very high level of efficiency when operated in favorable speed ranges. At the same time, the compromise of minimizing the number of gearshift operations per lap while maximizing the torques in accordance with the peak power stipulated by the regulations was achieved. Additional findings Economy and efficiency play a special role during Formula E. The aim is to use as little energy as possible and to recover as much energy as possible using recuperation (braking energy regeneration). As is the case with hybrid and electric vehicles, braking is carried out in Formula E using a conventional mechanical brake and using the electric machine. In this case, the latter functions as a generator and converts the energy released during deceleration back into electrical energy. “The interplay between the mechanical and electric brake is decisive. Motorsport races are also won using the brakes. We also require the knowledge needed here for the technology that is used in conventional vehicles”, says Prof. Peter Gutzmer. Ultimately, it is up to the Formula E drivers, Lucas di Grassi and Daniel Abt, to make sure they economize with the energy available to them. “As a racing driver, the first thing you have to learn is how to drive efficiently. If you’ve been competing in races from an early age, you don’t automatically have that running through your veins”, admits Daniel Abt. “From an early age, we learned to drive at full speed and fuel economy never really played a role”, continues the 23-year old. Lucas di Grassi is sure that efficient mobility not only matters in Formula E, but will also become the standard everywhere else. “Efficiency means combining the latest drive train technology with the best possible performance level and making the most intelligent use possible of the energy that is available.”