During the last edition of the 24 Hours of Le Mans, Peugeot y Total jointly announced their project to return to endurance racing through a hybrid hypercar of the new category LMH of Wec. The prototype will have a novel powertrain called Peugeot HYBRID4 500KW. The companies, partners for 25 years, provided the main characteristics of it.
The internal combustion engine will be a 6-liter 2.6 kW petrol biturbo V500 (680 horses) located in the central rear part that will be combined with a 200 kW electric drive (268 horses) which will be mounted on the front.
The intelligent powertrain and energy flow management system, key to high performance, will be developed under the leadership of Francois Coudrain, powertrain manager for Peugeot Sport's WEC program.
"The architecture of the Peugeot HYBRID4 500KW powertrain is the result of a very detailed summary conformed by the new WEC regulations", Coudrain pointed out. “We initially thought of a single turbo, but that would have prevented us from reaching our engine's target center of gravity. A V6 biturbo block offers the best trade-off between technology, weight, engine accessory packaging, reliability and performance. ", Agregó.
The vehicle will have Traction on the four wheels, will mount a seven-speed sequential robotic gearbox (plus reverse) that will be controlled by paddles on the steering wheel and a cable brake system that will be managed electronically.
The rider will be able to adjust the level of engine braking generated by the electric drive when decelerating and the force applied by the pads to the brake discs to achieve the optimal combination of electric / hydraulic braking.. Optimal energy management, both during acceleration and during energy recovery (limited by regulation to 200 kW), will therefore be key to the car's performance and efficiency.
The hypercar will use a high-density battery developed by Peugeot Sport, Total and their subsidiary Saft, who has worked for a decade in Formula 1. The selected cells favor power density over energy, in line with the needs of endurance racing. The battery will be fully integrated into the car and into the powertrain energy management process.
"The main parameter is to optimize the way in which the energy stored in the battery is used"Said Kamen nechev, CTO of Saft. “To achieve this requires an extremely short charging time combined with high-capacity storage cells to form a package that allows maximum power to be delivered as quickly as possible. The most competitive solution resides in the management of load optimization and the amount of energy available in real time ”.
The new battery will be located inside a carbon shell in the car's monocoque frame, behind the driver and under the fuel tank. It has been designed to combine optimal durability with consistent racing performance of up to 24 hours and even longer.. Total and Peugeot Sport are responsible for the homologation of the battery that will be assembled in a new workshop at the Peugeot Sport base in Versailles-Satory, near Paris.
THIS IS HOW THE PEUGEOT HYBRID4 500KW WORKS
Although the internal combustion engine delivers 500 kW and the electric unit has a capacity of 200 kW, regulations establish a maximum power output of only 500 kW during racing. To adapt to different racing situations, the LMh's powertrain works as follows:
- Regulations prohibit the use of electrical energy below 120 km / h therefore, the motor-generator set is only activated once this speed is reached. The car should be started from a standstill only with the power of its internal combustion engine.
- The V6 biturbo's power output is capped at 300 kW (408 hp) and is adjusted according to the power supplied by the motor generator unit at 200 kW, which is directly dependent on the battery level.
- When the electric motor is running, the car automatically switches to four-wheel drive, which changes its driving ability, for example in high-speed curves.
- When the high-density battery is empty, the internal combustion engine returns to power output of 500 kW (680 hp) and the transmission returns to rear wheel drive. During the races, the battery will be fully charged before the start by means of a plug-in hybrid charger connected to the mains. Once on the track, the battery will work completely independently and will be charged only by the kinetic braking energy recovery system.
However, the following exceptions are covered by the regulations:
- The power output of the internal combustion engine can be increased by three percent to 515 kW (700 horsepower) at the end of the straights when the battery is empty, so the electric motor works like a 15 kW alternator. This setting is applied automatically by the car electronics.
- The possibility of operating with the internal combustion engine or the electric motor, or both at the same time, in the pitlane or when the speed is restricted to 60 km / h. As required by regulation, the Hypercar will be equipped with specific sensors to monitor and transmit power levels measured at all four wheels to the FIA in real time to ensure the maximum performance specified by the Balance of Performance (BoP).
The first launch of the Peugeot and Total prototype is scheduled for the end of 2021. In the meantime they will continue with the powertrain engineering pending bench and simulator testing in the course of the first half of 2021.