Under the microscope: Mercedes-AMG Project ONE: Formula One technology for the road
The Mercedes-AMG Project ONE has had its world première at the International Motor Show (IAA) in Frankfurt: for the first time, the two-seater supersports show car brings the very latest and efficient, fully-fledged Formula 1 hybrid technology from the racetrack to the road almost par for par to represent the highlight of AMG's 50th anniversary. It is anticipated that this high-performance hybrid will produce over 1000 hp and reach top speeds beyond 350 km/h.
Ever since the early days of motorsport, engineers have dreamed of bringing motor racing technology to the road. Mercedes-AMG is now making this dream a reality at the very highest level.
The high-performance plug-in hybrid drive system of the Mercedes-AMG Project ONE comes directly from Formula 1, and was realised in close cooperation with the motorsport experts of Mercedes-AMG High Performance Powertrains in Brixworth (UK). It consists of a highly integrated and intelligently networked unit comprising a hybrid, turbocharged combustion engine with a total of four electric motors. One has been integrated into the turbocharger, another has been installed directly on the combustion engine with a link to the crankcase and the two remaining motors drive the front wheels.
The 1.6-litre V6 hybrid petrol engine with direct injection and electrically assisted single turbocharging comes directly from the Mercedes-AMG Petronas Formula 1 racing car. The four overhead camshafts are driven by spur gears. To enable high engine speeds, the mechanical valve springs have been replaced by pneumatic valve springs. The engine is placed ahead of the rear axle can easily reach speeds of 11,000 rpm, which is currently unique for a roadgoing vehicle. However, for higher longevity and the use of commercially available Super Plus petrol instead of racing fuel, it remains significantly below the F1 engine speed limit of 15,000 rpm.
The electric motors on the front axle are also true rev wonders, with rotor revolutions up to 50,000 rpm – current state of the art is a speed of 20,000 rpm.
The very high-revving engine is additionally boosted by a high-tech turbocharger. The exhaust gas and compressor turbines are separated from one another and located at an optimum position to the exhaust side and to the intake side of the V6 engine, and connected to one another by a shaft. This shaft features an electric motor with approximately 90 kW which, depending on the operating status, electrically drives the compressor turbine at up to 100,000 rpm – for instance when moving off or following load changes.
New all-wheel drive with purely electrically driven front axle
There will also be two further 120 kW electric motors at the front axle – a major difference to Formula 1 cars. Each is connected to a front wheel via a reduction gear. The fully electrically driven front axle allows individual acceleration and braking of each front wheel, and therefore selective torque distribution (torque vectoring), for particularly high levels of vehicle dynamics. With the axle motors, the estimation is that up to 80 percent of the braking energy can also be optimally used for recuperation under everyday driving conditions. This energy is stored in the battery and is available for a longer electric range. Each electric motor is controlled by its own power electronics located in close proximity to the electric motors in the floor assembly.
Lithium-ion battery with Formula 1 technology
The battery cells, their arrangement and the cell cooling system are the same as used in the Mercedes-AMG Petronas Formula 1 racing car. However, the quantity of battery cells in the Project ONE will make it significantly more practical for everyday use. The lithium-ion, high-voltage battery and the DC/DC converter supporting and charging the 12 V onboard electrical system are accommodated in space-saving configuration in the vehicle floor behind the front axle.
As a further innovation, the high-voltage EQ Power+ drive system operates at 800 volts instead of the usual 400 volts. Thanks to the higher voltage levels it is possible to significantly reducing the cable diameters, for example, thereby saving design space and weight.
Intelligent operating strategies for optimum output and efficiency
Overall, the high-performance plug-in hybrid drive system EQ Power+ offers numerous intelligent operating strategies, which are optimally tuned to different application scenarios. The driving modes range from all-electric operation through to a highly dynamic mode, which corresponds to a setting used in Formula 1 qualifying for optimum lap times.
Completely new, automated 8-speed manual transmission
Power is transferred to the rear wheels by an 8-speed manual transmission that has been developed from scratch for the Mercedes-AMG Project ONE. It is activated hydraulically and can be operated in automated mode or manually using the shift paddles.