The future of Mercedes-AMG is turning electric and as part of this combines high efficiency with additional driving dynamics. To implement this combination to optimum effect, the developers in Affalterbach are working intensively on innovative technologies which will take performance to a new level. The next vehicle generation will see the deployment of the electric exhaust gas turbocharger – eTurbo.
Mercedes-AMG is pressing ahead with electrification through innovative developments and as part of this is also benefiting from motorsport know-how. The latest achievement which is already in the final stages of development is the electric exhaust gas turbocharger, which in future will be used for the first time in a series production model from Affalterbach. Developed in partnership with Garrett Motion, this technology comes straight from Formula 1 and resolves the conflicting goals between a small, fast-reacting turbocharger which achieves relatively low peak performance and a large turbocharger with a high peak performance but which on the other hand can suffer from turbo lag.
Exhaust gas turbocharger with integrated electric motor: agility redefined The highlight of this innovative turbocharging system is a slim electric motor, measuring about 4 centimetres, which is integrated directly on the charger shaft between the turbine wheel on the exhaust side and the compressor wheel on the fresh air side. This electronically controlled electric motor drives the compressor wheel before this accepts the exhaust gas flow. The electrification of the turbocharger significantly improves immediate response from idle speed and across the entire engine speed range. The so-called turbo lag – the delayed response of a conventional turbocharger – is eliminated by the electric motor. The result is that the combustion engine responds even more spontaneously to accelerator pedal input, and the entire driving feel is significantly more dynamic and
agile. In addition, electrification of the turbocharger enables higher torque at low engine speeds, which also enhances agility and optimises acceleration capability from a standstill. Even when the driver takes their foot off the accelerator or applies the brakes, the technology of the electric turbocharger is able to maintain the boost pressure at all times, so that a continuous direct response is guaranteed.
The turbocharger achieves speeds of up to 170,000 rpm, which enables a very high rate of air flow. It can be operated via a 48-volt on-board electrical system. The turbocharger, electric motor and power electronics are connected to the combustion engine’s cooling circuit to create an optimum temperature environment at all times.
“We have clearly defined our goals for an electrified future. In order to reach them, we are relying on discrete and highly innovative components as well as assemblies. With this move we are strategically supplementing our modular technology and tailoring it to our performance requirements. In a first step this includes the electrified turbocharger – an example of the transfer of Formula 1 technology to the road, something with which we will take turbocharged combustion engines to a previously unattainable level of agility”, explains Tobias Moers, Chairman of the Board of Management of Mercedes-AMG GmbH.
This electric turbocharger is unlike existing 48V electric compressor technology found on ‘53’ AMGs and others. The new unit retains a conventional exhaust-driven side, and is closer in execution to what F1 fans may remember as ‘MGU-H’.