Ever since the early days of motor sports, 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.
“Motor sports is not an end in itself for us. Faced with intense competition, we develop technologies from which our production vehicles also subsequently benefit. We are drawing on our experiences and successes from three constructors’ and drivers’ world championships to bring Formula 1 technology to the road for the first time: in Mercedes-AMG Project ONE”, said Dieter Zetsche, chairman of the Board of Management of Daimler AG and head of Mercedes-Benz Cars.
“The Mercedes-AMG Project ONE is the first Formula 1 car with MOT [Ministry of Transportation] approval. Our highly efficient hybrid assembly stems from motor racing and the electrically powered front axle generates a fascinating mixture of performance and efficiency. With a system output of over 1,000 hp and a top speed beyond 350 kph, this hypercar handles exactly as it looks: it takes your breath away,” said Ola Källenius, eember of the Daimler AG Board of Management responsible for Group Research and Mercedes-Benz Cars Development.
The concept car gives specific indications of what to expect from the upcoming production model. “Project ONE raises the bar in terms of what is currently technologically feasible and thanks to its combination of efficiency and performance it represents an absolute benchmark. At the same time, Project ONE provides an outlook on how AMG will define driving performance in the future”, Tobias Moers explained as the head of Management at Mercedes-AMG GmbH.
One turbocharged engine and four electric motors
The high-performance plug-in hybrid drive system of the Mercedes-AMG Project ONE comes directly from Formula One, and was realized in close cooperation with the motor sports experts of Mercedes-AMG High Performance Powertrains in Brixworth. It consists of a highly integrated and intelligently networked unit comprising one 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-liter 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 achieve high engine speeds, the mechanical valve springs have been replaced by pneumatic valve springs. The vehicle is mid-engined (ahead of the rear axle) and it 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.
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 with up to 100,000 rpm – for instance when moving off or following load changes. The Formula 1 designation for this unit is MGU-H (Motor Generator Unit Heat).
The dreaded turbo lag – the delayed response to accelerator pedal commands owing to the inertia of the large charger – is completely eliminated. The response time is greatly reduced, and is even shorter than that of a naturally aspirated V8 engine. The electric turbocharger brings about another advantage: it uses parts of the surplus energy from the exhaust system to generate electricity, and either stores it in the high-voltage lithium-ion battery as part of recuperation or provides additional drive power by feeding it to an additional electric motor. This motor produces 120 kW, has been installed directly on the engine and features a link to the crankshaft via a spur gear (MGU-K = Motor Generator Unit Kinetic) – another technology that ensures maximum efficiency and performance in F1.
New all-wheel drive with purely electrically driven front axle
There will also be two further 120 kW electric motors at the front axle. 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, we estimate 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.
The thermal efficiency of the combustion engine with electric turbocharger (MGU-H) in conjunction with the electric motor on the crankshaft (MGU-K) will be over 40 percent. This is a previously unattained peak value for series production vehicles, and confirms the dominant position of the drive system where efficiency is concerned. This means that the show car obtains significantly more drive energy from one litre of fuel than other cars. It is therefore both economical and powerful. By way of comparison, the thermodynamic efficiency of conventional series production engines is around 33 to 38 percent.