Mercedes Power Unit Hardware & Software

[Tommy Cookers]

....... The MGU-K never passes the stipulated 120 kW.

the stipulated 120 kW ........ is actually 126 kW
because the limit point is where DC electrical power is going to the motor drive aka controller and is 120 kW + 5%
(the controller will cleverly chop that steady supply into chunks ideal for the motor action at any moment)
ie there is a 5% allowance notionally to compensate for losses downstream of that point
and so if the actual losses are less than 5% the power delivered added to the crankshaft power will legally be more than 120 kW

and necessarily there will be electrical energy stored in the motor controller
ie some accumulation of electrical energy (although fuel accumulation appears strictly taboo)
and of course there is mechanical energy stored in the MGU-K's rotation

so the 'legal 120 kW' may actually be 121 or 122 or 123 kW
and briefly the power delivery will exceed the above 121 or 122 or 123 kW

and .....,
are we sure that this limit applies when MGU-H-generated power is being directly used by MGU-K motoring ?
though important only if power recoverable from the exhaust turbine was more than 120 kW

[R_Redding]

and necessarily there will be electrical energy stored in the motor controller ie some accumulation of electrical energy (although fuel accumulation appears strictly taboo)

The controller can store a maximum of 5KJ ... so its not allowed to accumulate much.
As C = 2*Energy/V² and assuming a not unreasonable bus voltage of 600Vdc , that comes to just short of 28'000uF.

Rob

[trinidefender]

....... The MGU-K never passes the stipulated 120 kW.

the stipulated 120 kW ........ is actually 126 kW
because the limit point is where DC electrical power is going to the motor drive aka controller and is 120 kW + 5%
(the controller will cleverly chop that steady supply into chunks ideal for the motor action at any moment)
ie there is a 5% allowance notionally to compensate for losses downstream of that point
and so if the actual losses are less than 5% the power delivered added to the crankshaft power will legally be more than 120 kW

and necessarily there will be electrical energy stored in the motor controller
ie some accumulation of electrical energy (although fuel accumulation appears strictly taboo)
and of course there is mechanical energy stored in the MGU-K's rotation

so the 'legal 120 kW' may actually be 121 or 122 or 123 kW
and briefly the power delivery will exceed the above 121 or 122 or 123 kW

and .....,
are we sure that this limit applies when MGU-H-generated power is being directly used by MGU-K motoring ?
though important only if power recoverable from the exhaust turbine was more than 120 kW

Yes I am sure that the limit of 120 kW (or 126 kW if including all efficiency loss and things you mentioned) is there even when the MGU-H is sending electrical current directly to the MGU-K. The maximum power is limited but the energy is not.

[Pierce89]

The mgu-k cannot apply more than 120kw, anytime. (Aside, fron the 5% loss assumption mentioned above)

[PlatinumZealot]

I don't know how and why but I was told by someone reliable that is possible to have a boost from the hybrid system more powerful than just the 120 kW of the MGU-K, how can this be possible?

That claim was lost in translation.
It was an interview with honda yahuhisa arai. He said that mclaren lost more than the 120kw on the straights when they run out of ers deployment. This could be for various reasons.

[Powerslide]

beryllium probably is banned unless coated then it won't be much of an issue although they could be using something even more exotic using beryllium as a red herring, who knows

[LookBackTime]

google translate from Italian Magazine - 2016 Mercedes Engine

https://translate.google.com/translate? ... edit-text=

POWER UNIT: MERCEDES CONTINUES AGING DELL'HCCI PLUS
Even for beginners it is very clear that the history of engines speaks primarily of two distinct functions:
ignition (classic Otto engines or improperly called a "petrol")
ignition (classic diesel engines)
From a theoretical point of view, the diesel engines have the highest efficiency values ​​of spark ignition engines, besides not being characterized by heavy penalties in terms of efficiency at partial loads typical of spark ignition engines. But usually on sports cars they are installed ignition engines, petrol engines.

Mercedes from the first half of the 2000s has invested a lot of money to try to "put together" the positive characteristics of the two types of engines by eliminating this union the negative characteristics; to do whatever they have developed different concepts of combustion, in particular the solution called HCCI (Homogenous Charge Compression Ignition) or better known as DiesOtto. And it is an evolution of the technology that is making a difference in the power unit German.

Briefly, how does this "new" type "(HCCI base) engine? When the engine has to deliver full load behaves just like a normal petrol, with the spark that triggers the combustion of the air-fuel mixture and combustion" homogeneous ". But when the engine will run at partial loads, combustion occurs spontaneously by increasing the compression ratio as a simple diesel engine, which as we have said before has a better efficiency.

The secret is in being able to raise the bar of the intervention that is controlled by the ignition when the engine switches to operate as a "classic petrol". Mercedes honing month after month this stage, continues to find CV and to get especially specific consumption always lower, fundamental in modern Formula 1.

In the HCCI technology is going to generate a homogeneous mixture between fuel and air, similarly to what occurs in the spark-ignition engines, having, however, the combustion through compression of the same, as in compression ignition engines. The advantages which are they? What are interested in doing so the combustion mixture in its entirety without developed through a propagation of the flame front is typical of spark-ignition engines and without phenomena only diffusive typical of compression ignition engines.

But there are also problems; one of the main is in the pressure peaks (especially on the cylinders) and mechanical stresses that the mixture generates, usually not viable for the motor above the low to medium loads. And here is the continued evolution of Mercedes: already in 2015 there have been improvements in technology, though problems still had to cylinders have especially on Force India and the two Mercedes official as to require major changes to the internal combustion engine reliability has been introduced in Canada on the cars of Hamilton and Rosberg. Another step, fundamental to what we were told was made ​​with the engine introduced by Mercedes at Monza, where the famous rod of which we spoke just above, has been significantly raised but with all the problems that may ensue.

In addition to problems related to stress, the HCCI engines are characterized by a difficulty in controlling the combustion, a factor that makes it difficult for proper management of the engine are very irritating especially vibrations (remember what I said that caused problems on the first PU Mercedes Championship races in 2015?) that are generated and that resulted in some problems to the power unit of Germany, as well as in the first part of the championship even then in Monza and Singapore. And here is behind the great work he is doing in the Italian headquarters of Petronas Turin preparing synthetic fuels suitable for this type of engine. Without the fundamental contribution of Petronas, this type "innovative" engine could not function like it is working on spaceships Hamilton and Rosberg.

It is thanks to this technology that Mercedes boasts a return on its combustion engine very close to 50%, a value that when compared to common car seems almost science fiction.

The new power unit that will debut in Barcelona, ​​was made interventions aimed at solving the above problems encountered in the season finale but without forgetting the performance side of the drive unit (thanks to some new components with higher efficiencies) that will gain even horses.

[Gridlock]

So they re-invented the petrol engine, and petrol. Why am I starting to think Ferrari have their work cut out?

[turbof1]

A 50% conversion is actually huge. Revolutionary I'd say. I don't know what the conversion right now is for full electric cars, if you consider that some sort of fuel needs to be converted to electricity at an energy plant, converted to dc, transported to your home, supplied to your car and then ultimately being used to put force on the wheels. The electric engines themselves are very efficient at 80-90%, but that's unfair comparison since the energy is still delivered by external sources.

Does anybody know what the conversion rate is for your average city car? Wikipedia gives a number, but I'm not sure how trustworthy that is: around 18-20%. Suddenly F1 has become relevant again for road cars.

[R_GoWin]

Does anybody know what the conversion rate is for your average city car? Wikipedia gives a number, but I'm not sure how trustworthy that is: around 18-20%. Suddenly F1 has become relevant again for road cars.

Take your pick.
Gasoline vehicles:
http://www.fueleconomy.gov/feg/atv.shtml
Hybrids:
http://www.fueleconomy.gov/feg/atv-hev.shtml
All electric:
http://www.fueleconomy.gov/feg/atv-ev.shtml

You can also work through the tabs for energy losses through different drive cycles.

[ME4ME]

A 50% conversion is actually huge. Revolutionary I'd say. I don't know what the conversion right now is for full electric cars, if you consider that some sort of fuel needs to be converted to electricity at an energy plant, converted to dc, transported to your home, supplied to your car and then ultimately being used to put force on the wheels. The electric engines themselves are very efficient at 80-90%, but that's unfair comparison since the energy is still delivered by external sources.

Why is that unfair? Not sure what you're onto about. If you're going to analyse from raw material till delivered energy at the wheels, you might as well do it for the fuel that powers the F1 engines, starting with drilling a hole in the ground and pumping the unraffinated oil out.

[turbof1]

A 50% conversion is actually huge. Revolutionary I'd say. I don't know what the conversion right now is for full electric cars, if you consider that some sort of fuel needs to be converted to electricity at an energy plant, converted to dc, transported to your home, supplied to your car and then ultimately being used to put force on the wheels. The electric engines themselves are very efficient at 80-90%, but that's unfair comparison since the energy is still delivered by external sources.

Why is that unfair? Not sure what you're onto about. If you're going to analyse from raw material till delivered energy at the wheels, you might as well do it for the fuel that powers the F1 engines, starting with drilling a hole in the ground and pumping the unraffinated oil out.

That's a good point actually. My reasoning however is that a lot of energy is already wasted before it reaches the battery in the case of hybrids/full electrical cars. It's not like electric power is some sort of magic energy coming out of your wall. It's energy converted from other energy, and electric cars themselves being that efficient masks it.

You do make a good point though: there's a lot of energy put in processing oil into car gasoline or diesel.

[taperoo2k]

A 50% conversion is actually huge. Revolutionary I'd say. I don't know what the conversion right now is for full electric cars, if you consider that some sort of fuel needs to be converted to electricity at an energy plant, converted to dc, transported to your home, supplied to your car and then ultimately being used to put force on the wheels. The electric engines themselves are very efficient at 80-90%, but that's unfair comparison since the energy is still delivered by external sources.

Why is that unfair? Not sure what you're onto about. If you're going to analyse from raw material till delivered energy at the wheels, you might as well do it for the fuel that powers the F1 engines, starting with drilling a hole in the ground and pumping the unraffinated oil out.

That's a good point actually. My reasoning however is that a lot of energy is already wasted before it reaches the battery in the case of hybrids/full electrical cars. It's not like electric power is some sort of magic energy coming out of your wall. It's energy converted from other energy, and electric cars themselves being that efficient masks it.

You do make a good point though: there's a lot of energy put in processing oil into car gasoline or diesel.

It's the usual calculation - how much energy do you to put into a process vs the amount of energy you get at the end of it. That tells you how cost effective or efficient/inefficient a process is. If Mercedes are getting near 50% as quoted in the article then that will send ripples through F1 and the car industry as a whole.

[Tommy Cookers]

]A 50% conversion is actually huge. Revolutionary I'd say. .....

....If Mercedes are getting near 50% as quoted in the article then that will send ripples through F1 and the car industry as a whole.

by efficient we mean what ?
not a near 50% efficiency at all powers - it doesn't and cannot exist
anyway some existing and upcoming SI (and CI) car ICEs are over 40% efficient at plausibly useful powers
(and as a hybrid PU with KE recovery can show 'near' 50%)

the prime factor in road cars is the falling of efficiency at the (small) partial powers that dominate
the SI suffering particularly as it cannot (because of the NOx catalyst) use a lean mixture to reduce throttling
what is the BTE/efficiency of the F1 Merc at 10 or 20 or even 30hp ?

60 years ago aviation was dominated by exhaust recovery in piston engines (so F1 has nothing fundamentally new)
adding 'free' 6% to crankshaft power at 50% power and 18% 'free' at 100% power ie an 18% efficiency gain
the makers 'only' had to design the engine to work well between 50 and 100% of takeoff power
clearly the 50% was compromised

for 'road relevance' Merc etc need the engine to work well at eg 5% power
in this it is helped by hybridisation, but millions of other-type cars are already doing that every day
as another poster said, the F1 type engine concept (and its cost) must be weighed against the other hybrid methods (and cost)

[Cold Fussion]

I don't know anything about that source but it seems to me that the author has taken the idea that Mercedes (the actual mercedes) have been doing HCCI research for a decade and taken the idea that HCCI is efficient and suspected vibration issues and decided that Mercedes HPE are using HCCI in their F1 engines. What is the actual evidence/source that Mercedes HPE are using HCCI? Furthermore, does it even make sense to have HCCI combustion in an F1 engine?