not in the rules: mguK can be drived when u want.. but can harvest only 2mj/l underbraking.
Thank you henry, that answers my question perfectly. But one thing I do not fully understand is how the energy transfer through the mgu-h into the energy storage works.henry wrote: ↑Thu Apr 11, 2019 5:36 pmThere are two ways in which the MGU-K can generate.
The first is to slow the car under braking, extracting kinetic energy.
The second is to place a load on the ICE, extracting energy that would otherwise go to the wheels.
The second method is applied in various ways.
1. At low speeds, typically at the beginning of straights, when part throttle is demanded the ICE creates more power than is demanded and the MGU-K extracts power from the crank to make the power at the wheel match what the driver is demanding.
2. At high speed, at the end of straights, the ICE continues at full power and is used MGU-K to reduce the power going to the wheels and charge the ES.
3. Sometimes, at the end of braking events at speed below which there is insufficient traction to generate 120kW from the MGU-K (around 100kph) the ICE drives the MGU-K to supplement the power coming from the rear wheels. This is probably contentious but I believe I observed this with Honda at Monza last year. It has some other potential benefits.
4. The MGU-K charges the ES by transferring energy indirectly through the MGU-H using its rotational inertia. This route was publicised by Honda. It is done at the end of straights as in 2 above, and is used to exceed the 2MJ restriction for MGU-K to ES.
Using these techniques the teams can always obtain 2MJ even when, as noted by @FPV GTHO, the available braking energy is often around 1MJ.
The MGU-H generates energymainly at full throttle where it is possible the best PUs are generatingvatv70kW. I would expect that they can also provide some power at part throttle. If a lap is 60 seconds full throttle the MGU-H might be expected to generate in excess of 4.2MJ.
So 2 from the K and 4.2 from the H pretty much matches the 30/70 split suggested above.
Of course in the race the teams probably choose not to use the methods that drive the MGU-K from the ICE because they increase fuel consumption in which case the K proportion would go down. But of course they also have the option to coast at the end of straights to save this fuel energy to be used at the beginning of straights where it is most valuable.
right.. direct harvest (energy from K to Es): braking zone.. and 2 mj/l limit.henry wrote: ↑Fri Apr 12, 2019 11:05 am
what Honda calls the 'extra harvest' cycle
I did not say "under braking is in the rules" What I did was expressing my opinion on this here discussion forum and subject (second try have been let through) From among some more posts which weren't. and I have no problem with anybody disagreeing with my expressed opinion. but apart from expressing my opinion on this here subject my last (second try post) I was actually quoting from F1 official site 12-14 April 2019.
Second try in answering:- So now I am being told that one way the 'K' can harvest without the brake pedal being used is "The driver requests 50% power (50% throttle) from the engine, and the ECU could apply 'full throttle' to the ICE and harvest 50% through either 'K' or 'H'. just imagine me posting such technicalities on here.Tzk wrote: ↑Sat Apr 13, 2019 8:35 pmI wouldn‘t expect the f1 site to be always correct and neither use it as valid source. Sometimes they overgeneralise to better explain it in laymens terms. What‘s written in technical directives and the rules is what counts.
That being said, yes you can harvest from the mgu-k under braking to prevent giving the energy away as heat. But you could also harvest from the mgu-k while either off throttle or not under full load.
Now, how would that work? Well, the driver controls the power at the wheels through the accelerator pedal. What happens inbetween doesn‘t matter. If for example the driver requests 50% power from the engine, the ecu could apply full throttle to the ice and harvest 50% through either mgu-k or -h. As long as the requested power arrives at the wheels, that‘s fine.
You may harvest through the mgu-k under braking, but you‘re not limited to this usage