The turbocharger has, in recent times especially, been quite popular with the car engine manufacturers. They help to increase the torque, power of the engine without compromising on the efficiency. The invention and usage of turbos dates back a long way in the engine development timeline and there are many advancements being made even to this day to squeeze the maximum potential out of them. But these technologies can only so much be developed and after a while, it is just money throwing in the R&D department without much of an output. And by the looks of it, that day is nowhere near for our beloved turbocharger.
The F1 teams are considered a benchmarks in the technological advancements that may be later used in the road going passenger cars. That have once again proved this by enhancing the performance of the turbo even more.
The many cars of Grand Prix this year will see an addition of a motor-generator unit which will share its shaft with the turbocharger. This means that at high RPMs, the exhaust gases will compress inlet air as well as generate electricity for the car’s hybrid system.
And it doesn’t stop here. The unit will also function as a motor so that at low RPMs, the turbo can be spooled up using the battery power to eliminate turbo lag.
Going a little more detail of its working, the motor-generator unit has 2 sub units. One is the MGU-H (Heat Motor Generator) and the other one is the MGU-K (Kinetic Motor Generator).
The MGU-H is essentially an electric motor connected to the turbocharger’s impeller shaft. As engine RPM rises, and the hot exhaust gases spin the turbo up to its 100,000 RPM peak, this motor can operate as a generator, converting heat energy from the exhaust gas into electricity. That electrical energy is then sent directly to the lithium-ion battery pack for use later, much like the KERS system F1 cars use. When, the driver needs an additional torque at low RPMs, say at the end of a corner, the same stored energy runs a motor that drives the turbos to provide an instant burst of acceleration. All this means that that cars will sip on only two-thirds of the fuel they did last year.
The automotive companies are not commenting on when will be able to see this tech in the road cars but that day may not be too far. While this idea may seem far-fetched at this point of time, research is being carried on on how to improve the efficiency of a turbo that may be more practical and production ready.
Take for example VW’s TwinCharger technology or Volvo’s Drive-E concept.
Both these work on the concept of using a turbo as well as a supercharger. The supercharger operates in low RPM conditions to provide boost without lag. When the RPM increases, the engine switches to the turbo for compressing air. This way optimum power can be extracted from the engine at all RPMs.
Another company that is developing this technology is called Eaton Corporation. Many might not heard of it but it is a major powertrain manufacturer. The chaps at Eaton are also developing a concept wherein an electrically driven supercharger provides the boost at low RPMs, with the turbo kicking in as the needle nears the redline.
Now it is just a matter of time before the concepts become production-ready. It will be really interesting to see these new technology at work on the roads and how it will behave in the real world.