Turbos are going electric—and becoming part of hybrid powertrains

[Daox]

Interesting article on how hybrid electric turbos are moving to mainstream vehicles. For those that don't know, formula 1 has been using these for years now.

https://www.greencarreports.com/news...id-powertrains

[Hersbird]

That's cool. At first I assumed they meet the turbo was powered by electricity entirely rather than exhaust and thought how dumb is that. But being a hybrid exhaust/electric makes more sense. Never give up taking free energy out of the exhaust.

[freebeard]

Beyond that, being electric it can switch from regen to boost instantly. BMW used this with a small secondary turbo that just eliminated lagging.


I guess TFA says that.

[cRiPpLe_rOoStEr]

Since BMW and Formula 1 were mentioned, it's worth to remind BMW was the last engine supplier to have ever used a production-based engine. AFAIK it was also the last 4-pot to race at Formula 1, and was more plagued by turbo-lag than some V6 counterparts which resorted to a pair of smaller turbochargers instead of a larger single one.

Well, even though I wouldn't hold my breath for another production engine to be turned into a Formula 1 powerplant, maybe a more effective turbo-lag mitigation can increase the acceptance not only of downsizing in general but also of a smaller amount of cylinders within some random displacement range, such as the 2.7L engines fitted to the 4-cyl Silverado and the V6 F-150.

[redpoint5]

I'd like to see AI racing. Perhaps what is learned on the track can be useful in future iterations of autonomous driving.

[California98Civic]

That's really cool. A mild hybrid for cruising and a relatively simple system for performance boost. Engineering is as cool as mechanics and hacking.

[rmay635703]

Originally Posted by freebeard

Beyond that, being electric it can switch from regen to boost instantly. BMW used this with a small secondary turbo that just eliminated lagging.


I guess TFA says that.

Primarily this reduces the temperature of the intake air, likely a good thing for detonation and power

[cRiPpLe_rOoStEr]

Originally Posted by rmay635703

likely a good thing for detonation and power

That's a good point. On a sidenote, the increased cooling is one of the reasons why ethanol has been more popular among high-performance operators.

[serialk11r]

This kind of setup likely doesn't generate much power, for that you need to split the shaft so the compressor can be stopped.

The issue with traditional turbos is that you need to add restriction to the turbine to deliver enough shaft power for response and low rpm boost. Adding an electric motor on the shaft lets you use electrical power to spin the compressor up when there's not enough exhaust going through the turbine.

To harvest energy efficiently, the turbine needs to be spinning pretty quickly to serve as an efficient impulse turbine, but having a compressor attached that also has to spin quickly is counterproductive. In F1 this isn't a problem since the engines run full throttle but on a street car running at part load, spinning the compressor is a waste of energy.

It's much more of a throttle response upgrade than anything else.

[cRiPpLe_rOoStEr]

Originally Posted by serialk11r

This kind of setup likely doesn't generate much power, for that you need to split the shaft so the compressor can be stopped.

Stopping the compressor and decoupling it from the turbine doesn't seem to be any beneficial.