Automotive

Mercedes-Benz partners with Garrett to build electric turbochargers

Mercedes-Benz partners with Ga...
Coupling a small electric motor to a turbocharger will help Mercedes-Benz eliminate turbo lag, allowing engines to run bigger, more powerful and more efficient turbo systems without affecting responsiveness
Coupling a small electric motor to a turbocharger will help Mercedes-Benz eliminate turbo lag, allowing engines to run bigger, more powerful and more efficient turbo systems without affecting responsiveness
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Coupling a small electric motor to a turbocharger will help Mercedes-Benz eliminate turbo lag, allowing engines to run bigger, more powerful and more efficient turbo systems without affecting responsiveness
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Coupling a small electric motor to a turbocharger will help Mercedes-Benz eliminate turbo lag, allowing engines to run bigger, more powerful and more efficient turbo systems without affecting responsiveness
The electric turbo mounted on a test engine
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The electric turbo mounted on a test engine
Developed in conjunction with Garrett, these electric turbos will spin at up to 170,000 rpm
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Developed in conjunction with Garrett, these electric turbos will spin at up to 170,000 rpm
Innovative High Performance Antriebskomponenten made by Mercedes-AMG, elektrifizierter Turbolader // Innovative High Performance drive components made by Mercedes-AMG, electrified turbo charger
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An electric motor behind the turbine can efficiently spin the turbo up to speed before the exhaust gases are coming through strong enough to do the work
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In partnership with the famed turbo snail-smiths at Garrett, Mercedes-Benz has announced it's developing electrically-assisted, 170,000 rpm turbochargers to eliminate turbo lag and boost the efficiency of its combustion engines.

Forcing additional pressurized air into your combustion chambers is a highly efficient, fuel-saving way to pull extra power and torque out of an engine. Turbocharging, which uses the energy of your exhaust gases to spin up a turbine to compress and force that air in, is a particularly neat and efficient way to do it, especially when compared to supercharging, which typically uses a belt running off the crank to spin up the turbines, sipping power from the engine.

The problem with turbos, particularly juicy big ones, is that they can take some time to respond. Turbo lag is a well-known phenomenon in which a driver might be idling along going down the street, then decide to go for an overtake and lay a boot into the throttle. It can take time for the extra exhaust gas flow to spin the turbo up to a high enough speed to match the fuel intake and boost the engine, and that results in an annoying delay in the power delivery that most automakers aren't happy letting out the door. Instead, they often go with smaller, more responsive turbos that don't deliver the same power and efficiency gains, but are more pleasant to drive.

Hence this collaboration between Mercedes-Benz and Garrett, a company that's been making turbos since 1954, and has more or less become synonymous with the mighty snail. Garrett has been investing in electric turbo technology in recent years, effectively using an electric motor on the back of the turbo scroll to spin the compressor turbine up to speed. This eliminates turbo lag, and the electric motor's contribution can drop back to nothing as soon as the exhaust gases are moving through fast enough to pick up the slack.

Innovative High Performance Antriebskomponenten made by Mercedes-AMG, elektrifizierter Turbolader // Innovative High Performance drive components made by Mercedes-AMG, electrified turbo charger
An electric motor behind the turbine can efficiently spin the turbo up to speed before the exhaust gases are coming through strong enough to do the work

When you take your foot off the pedal, Garrett's E-Turbos can also regeneratively brake the turbo shaft to harvest its spinning energy back into the car's 48-volt electrical system – but Mercedes may have chosen to take things in a different direction. "Even when the driver takes their foot off the accelerator or applies the brakes," reads a press release, "the electric turbocharger is able to maintain boost pressure at all times, so that a continuous and direct response is assured."

The phrasing there leaves open the possibility for multi-mode operation; perhaps this setup could keep the turbo spinning fast in a sports mode for the maximal possible responsiveness at the expense of some wasted energy, and go back to harvesting turbo spool-down energy in regular street mode driving. This is pure speculation; the Mercedes release makes no mention of it.

"We have clearly defined our goals for an electrified future," said Tobias Moers, Chairman of the Board of Management of Mercedes-AMG. "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."

The future may be fully electric, but the present still uses plenty of fossil fuels, and initiatives like this will hopefully save many a gallon.

Source: Mercedes-Benz

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7 comments
Simon Redford
Very interesting! When not running for thrills, the ability to recover exhaust power in generator mode could provide a good alternative to the alternator for battery charging. See the TIGERS® (Turbo-generator Integrated Gas Energy Recovery System) from Tenneco for an exhaust gas power recovery product and add a compressor. See also Electric Turbo Compounding for large gensets from Bowman Power in the UK. Could it also be adapted for small gas turbine power generation products?
paul314
Eventually they're going to have capture the nerve impulses to start spinning up the turbo before you even finish thinking about stomping on the gas. Or people could just drive a little less aggressively.
Gregg Eshelman
Formula 1 will be banning the technology in 3, 2, 1...

If the intake air could be switched between going directly in and through the turbo, the electric motor could be used to keep the thing spinning for better exhaust scavenging, especially at idle.
guzmanchinky
I have a new E400, and it has a turbo, and as far as I can tell, absolutely zero turbo lag. I'm pretty sure my next car will be electric, also with no turbo lag.
Eddy
Connects to the car's 48v electrical system !! This is indeed going to be a Mercedes priced ad on, I wonder how long the bearings will last at 170000 RPM.
Tony Morris
"When you take your foot off the pedal, Garrett's E-Turbos can also regeneratively brake the turbo shaft to harvest its spinning energy back into the car's 48-volt electrical system". Not so. Harvesting is done when the turbocharger reaches maximum boost and a wastegate would otherwise be needed to dump excess energy to the exhaust system. The generator brakes the turbo shaft, controlling boost and generating electricity.
ajl12no
Shame to see Daimler-Benz still barking up the wrong tree. Like Blackberry (RIM) they're finished if they keep pursuing ICE's. Electric turbo is a waste of time, money and energy. Fossil fuels have now been proven to be strictly for fossils. Electric cars will take over any minute now...Wakey wakey Benz!