MERCEDES-AMG is driving technology taken straight from its exploits in Formula 1 straight onto the streets with a new electric turbocharger that promises lag-free performance, already slated to be fitted to production cars in the near future.
The new unit has been fitted with a 40mm electric motor on its spindle which drives the compressor wheel on the fresh air side of the turbocharger and is electronically controlled to spool up before the turbo accepts the ‘regular’ exhaust gas flow.
This means immediate response from the turbo from idle speed and across the entire engine speed range and eradicates turbo lag.
Now in its final stages of development at AMG’s Affalterbach factory, the technology has been used in Formula 1 for a number of seasons now and is expected to be implemented be on a future version of the 2.0-litre M139 engine used in the AMG A45 S.
In its current guise, the highly-strung four-cylinder produces up to 310kW/500Nm, but power and torque could be significantly boosted by the new tech, although Mercedes-AMG has not indicated any potential numbers for the unit.
The brand says the new turbo was developed in partnership with Garrett Motion and claims to resolve the conflicting goals of a small, fast-reacting turbocharger a large, more lag-stricken unit turbocharger with higher peak performance.
The new electric turbo is different to the boosted system in existing models such as the E53 which has a separate compressor driven by an electric motor which forces air into the engine directly or via the other, traditional turbocharger.
Unlike the new unit, the E53’s booster is a separate device from the turbocharger. Audi use similar pre-booster for models including the SQ7 SUV.
In a statement, Mercedes-AMG said “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,” it said.
“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’s electric motor is plugged into the car’s 48-Volt on-board electrical system and spins at up to 170,000rpm for a very high rate of airflow.
Tobias Moers, Mercedes-AMG’s outgoing chairman and from August, the new head at Aston Martin, said the company had “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,” he said.
“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.”
Mr Moers indicated the future of electrification and modular technology could see the new electric turbo fitted to the M139 engine and eventually become the powerplant for the bigger range of Mercedes-Benz and AMG sports models, including the C-Class.
Mercedes-Benz has already stated that developments of its inline six-cylinder engine could see the end of the V8 in its performance cars such as the C63 and even the possibility of being replaced with four-cylinder hybrid powerplants.
The development of the electric-turbo engine paves the way for increased performance with less weight than a six or eight-cylinder, and has packaging efficiencies to allow integration with electric motor assistance.