Electric Turbo Spool

[Andy6]

Ok so this is a bit out there...

I've been wondering about the feasibility of adding an electirc motor to a turbo to spool it at lower RPM's to eliminate turbo lag in roughly the same way as the F1 cars do thesedays. So I thought I'd see what people on here thought about it and what would need to be considered technically to achieve, if it's even possible.

Here are my thoughts.

F1 engines and other "hybrid" systems uncouple the compressor and turbine so they can spin at different RPM's, during energy recovery and spooling the turbo. In terms of simplicity could a motor simply be attached to one side? If so would this create some sort of vacuum effect on the hot side during, a pressure difference either side of the exhaust valves probably isn't ideal.

Control side: Initially I though a simple button to spin the motor might suffice, making the circuit relatively simple. However I think it might create overboosting problems. Adding in some sort of RPM limit on the motor might solve this, but is boost pressure fixed to compressor speeds?
Other than this I guess an automated system is the next option. In my mind this would involve taking Engine RPM's and throttle postion to control the electric motor speed and therefore boost pressure, steadily reducing as exhaust gas pressures increase. Im guessing this would need a new ECU to add the control to the electric motor by altering voltage to it.

Any ideas?!

 

[RsvRob]

Might aswell fit a super charger to eliminate lag before the turbo spins up

 

[Andy6]

With a SuperCharger the ratio of engine speed to compressor speed is fixed, so at low engine speeds the compressor speeds are also low, and also doesn't allow for alterations and fine tuning. Secondly Superchargers add load to the crank that the engine has to overcome whereas turbos harvest otherwise wasted heat engery from the exhaust.
And it's not really what I was getting at, I was mearly wondering what peoples thoughts where on the technical aspect of doing this.

 

[RsvRob]

And they are my thought's lol. Unless you have a big budget like a race team then all the work to gain quicker spool via the method you suggest is no good £/rpm gain.
You'd be better identifying a turbo that has a bhp rating you want with all the internal work done for quick spool.
Titanium parts
Ball bearing chra
Etc

 

[Andy6]

Haha yep true but that's so conventional! I think slinging on some sort of adaptor and elec motor wouldn't be hugely expensive if it's even possible/safe, but adding control circuits to it would require much more in depth detail and I wasn't sure if I had considered everything hence the post. But it is more of a thought provoking exercise rather than a genuine upgrade consideration.

 

[Simon@NTS]

Ok so this is a bit out there...

I've been wondering about the feasibility of adding an electirc motor to a turbo to spool it at lower RPM's to eliminate turbo lag in roughly the same way as the F1 cars do thesedays. So I thought I'd see what people on here thought about it and what would need to be considered technically to achieve, if it's even possible.

Here are my thoughts.

F1 engines and other "hybrid" systems uncouple the compressor and turbine so they can spin at different RPM's, during energy recovery and spooling the turbo. In terms of simplicity could a motor simply be attached to one side? If so would this create some sort of vacuum effect on the hot side during, a pressure difference either side of the exhaust valves probably isn't ideal.

Control side: Initially I though a simple button to spin the motor might suffice, making the circuit relatively simple. However I think it might create overboosting problems. Adding in some sort of RPM limit on the motor might solve this, but is boost pressure fixed to compressor speeds?
Other than this I guess an automated system is the next option. In my mind this would involve taking Engine RPM's and throttle postion to control the electric motor speed and therefore boost pressure, steadily reducing as exhaust gas pressures increase. Im guessing this would need a new ECU to add the control to the electric motor by altering voltage to it.

Any ideas?!

VGT

 

[Andy6]

Trouble with Variable geometry is you are still having to accellerate the same mass with the same exhaust temps and pressures, and you're still not going to be able to get 2 bar of boost at 1000 rpm for example.