Honda Power Unit Hardware & Software

[mzso]

You do have to sacrifice ICE power to gain MGU-H power, likewise you have to sacrifice ICE power to harvest from the MGU-K.

I doubt this is the case. Since energy storage from the K is sorely limited (I wonder why though) regen-breaking should be more than enough to collect this energy.

It isn't, you are using engine breaking to harvest via the K. Maybe if you were harvesting from the front wheels it would be a different story. Besides you still have to burn gasoline to accelerate the car so that you can harvest with the K. Fuel is always burned before recovery with either machine can happen.

Even so it takes away energy from the car's kinetic energy, rather than ICE power, which is not producing useful power during breaking. The turbo is even absorbing power via the H to keep up the spin.
You burn fuel to accelerate the car to be fast, not relevant to regen. Regen only recovers some of the energy (otherwise only used to heat the break discs) you must waste because you need to slow down the car for a turn.

[godlameroso]

I doubt this is the case. Since energy storage from the K is sorely limited (I wonder why though) regen-breaking should be more than enough to collect this energy.

It isn't, you are using engine breaking to harvest via the K. Maybe if you were harvesting from the front wheels it would be a different story. Besides you still have to burn gasoline to accelerate the car so that you can harvest with the K. Fuel is always burned before recovery with either machine can happen.

Even so it takes away energy from the car's kinetic energy, rather than ICE power, which is not producing useful power during breaking. The turbo is even absorbing power via the H to keep up the spin.
You burn fuel to accelerate the car to be fast, not relevant to regen. Regen only recovers some of the energy (otherwise only used to heat the break discs) you must waste because you need to slow down the car for a turn.

So how did the car gain kinetic energy in the first place? It had to burn fuel. In your road car when you downshift, you get engine breaking, in F1 the MGU-K is acting like an engine break as well. The MGU-K is putting a load on the engine, which is connected to the drive train. The MGU-K can put a load on the engine at any time. In fact it can act like partial TC.

[mzso]

So how did the car gain kinetic energy in the first place? It had to burn fuel. In your road car when you downshift, you get engine breaking, in F1 the MGU-K is acting like an engine break as well. The MGU-K is putting a load on the engine, which is connected to the drive train. The MGU-K can put a load on the engine at any time. In fact it can act like partial TC.

Doesn't seem like you read my whole comment, or completely missed the point. Gaining the kinetic energy is of no relevance whatsoever, that happened in the acceleration phase and the K even added to it.

While breaking you must shed a good part of that energy to slow down. So it takes energy from the brake discs not the engine. You should view it as "putting load" on the car's inertia, if anything. It recovers energy, that otherwise would be wasted as heat.
(It could harvest energy from the ICE, but I don't think that even makes sense in Monza)

AS for actual ICE engine breaking, maybe that can offload some work from the real brake discs, if it even makes sense (has advantages), otherwise they need to minimize it.
You need to keep up the RPM to provide maximum power ASAP after taking the turn.

[godlameroso]

While breaking you must shed a good part of that energy to slow down. So it takes energy from the brake discs not the engine. You should view it as "putting load" on the car's inertia, if anything. It recovers energy, that otherwise would be wasted as heat.
(It could harvest energy from the ICE, but I don't think that even makes sense in Monza)

AS for actual ICE engine breaking, maybe that can offload some work from the real brake discs, if it even makes sense (has advantages), otherwise they need to minimize it.
You need to keep up the RPM to provide maximum power ASAP after taking the turn.

The energy is being taken from the drivetrain's inertia, the MGU-K is geared to the engine, when the MGU-K goes into generator mode it puts a load on the crankshaft, that load is sent through the clutch, gearbox, axles, wheel bearings and finally into the wheels. This is what slows down the car, it's also how it's sped up when it goes into motor mode. No matter what, the MGU-K is harvesting energy from the engine directly. The fuel you burned to move the car gets burned whether you recover it or not, but since you have the option to do so, you should.

On a complete tangent:

Other options are to recover some of the energy at part throttle or traction limited zones. Honda does this with their 'extra harvest' where they syphon engine power through the MGU-K, send it to the MGU-H and then to the ES for extra deployment. If you throw in the MGU-H's ability to send power, you can in essence nullify a great deal of parasitic losses in the engine.

The MGU-H is directly connected to the turbo, and the pressure system is directly coupled to engine power, as it delivers the oxygen burned by the ICE, in a way the turbine is connected to the engine via fluid coupling, which means it's indirectly connected to the MGU-K. To me, any output from the MGU-H counts towards the total ICE output, energy cannot be created or destroyed, it only changes form. 600KW from the ICE can only happen if the MGU-H is supplying the compressor with 60KW of energy, so the ES is deploying 180KW to allow that to happen.

This means that without the MGU-H engine output would be 540KW.

[63l8qrrfy6]

mzso is technically correct.

The kinetic energy lost during braking is 0.5*mass(initial velocity - final velocity) which, neglecting other lesser losses, is equal to the work done by the drag force + the energy dissipated by the brakes. As mzso correctly states the MGUK recovers some of the energy that would otherwise be dissipated as heat by the brakes.

A very good example is Canada 2014 where both Mercs overheated the MGUK control electronics causing the motor to stop harvesting which in turn caused the rear brakes to overheat.

[godlameroso]

mzso is technically correct.

The kinetic energy lost during braking is 0.5*mass(initial velocity - final velocity) which, neglecting other lesser losses, is equal to the work done by the drag force + the energy dissipated by the brakes. As mzso correctly states the MGUK recovers some of the energy that would otherwise be dissipated as heat by the brakes.

A very good example is Canada 2014 where both Mercs overheated the MGUK control electronics causing the motor to stop harvesting which in turn caused the rear brakes to overheat.

How does the MGU-K recover that energy? Is it geared to the brakes or the engine? If the latter then it is directly harvesting the inertia of the engine. The engine is coupled to everything, including the chassis, so much like the MGU-H it's harvesting heat energy indirectly.

[63l8qrrfy6]

You can't "harvest inertia" that makes no sense. Yes - the load (torque) path does go through the engine but it does not change anything. Actually one can imagine the MGUK during harvesting as another brake disc that stores the energy rather than dissipating it. Any braking the MGUK does is energy taken away from the actual rear brakes - it can't come from anywhere else.

Just to avoid any confusion - when we say "energy taken away from brakes" what that means is energy that would otherwise go to the brakes. No one claims that the MGUK actually harvests directly from the brakes or anything to that effect.

[godlameroso]

You can't "harvest inertia" that makes no sense.

It does to me, harvesting/harnessing/collecting some of the inertia of the crankshaft by putting a load on it to generate electrical energy.

[63l8qrrfy6]

You can't "harvest inertia" that makes no sense.

It does to me, harvesting/harnessing/collecting some of the inertia of the crankshaft by putting a load on it to generate electrical energy.

How many joules is one inertia ?

[godlameroso]

You can't "harvest inertia" that makes no sense.

It does to me, harvesting/harnessing/collecting some of the inertia of the crankshaft by putting a load on it to generate electrical energy.

How many joules is one inertia ?

~150,000

[hollus]

The last many pages have been mostly about generic aspects of the PUs that are not specific to the Honda PU. The same is happening regularly in the Ferrari, Renault and Mercedes's PU threads.
This is allowed to stay as the discussion(s) apply indirectly to the hosting threads and because the discussions are informative and useful, and we have all learned to find them in any of the 4 different PU threads, haven't we?

But this makes discussion on the actual individual PUs extremely difficult, with pages of generic PU chat separating the on-topic discussions.

This is a reminder that there is a thread for generic aspects of the current generation of PUs:
2014-2020 Formula One 1.6l V6 turbo engine formula
Discussion that concerns all PUs would be much more focused there, which would also remove the need to have each line of discussion repeated 4 times over.

A pair of posts on the larger origin of grid energy have been removed as too far off topic, while the rest is allowed to stay (as usual, but unwillingly so from a Mod's perspective).

Anyone who things that this sort of off-topic (on-topic as PU related but off-topic as not specific to the thread's PU as exemplified by the last two pages) should be moved to the generic PU thread, feel free to PM me. Anyone opposed to it feel equally free to PM as well! This way we can hopefully gauge the opinion of most posters

[63l8qrrfy6]

It does to me, harvesting/harnessing/collecting some of the inertia of the crankshaft by putting a load on it to generate electrical energy.

How many joules is one inertia ?

~150,000

No, that's complete bollocks.
Moment of inertia has units of kg*m^2 - which are most definitely not Joules.

You can't "harvest inertia" just as you can't harvest density or volume!

[gruntguru]

You are correct but you also need to remember that the rolling resistance is proportionate to the square of speed so you need more power in higher speeds than lower speeds to accelerate.

More importantly - Acceleration is proportional to Power divided by Velocity so even with zero rolling and aero resistance, you need a a lot more power at high speed.

[gruntguru]

I doubt this is the case. Since energy storage from the K is sorely limited (I wonder why though) regen-breaking should be more than enough to collect this energy.

It isn't, you are using engine breaking to harvest via the K. Maybe if you were harvesting from the front wheels it would be a different story. Besides you still have to burn gasoline to accelerate the car so that you can harvest with the K. Fuel is always burned before recovery with either machine can happen.

Even so it takes away energy from the car's kinetic energy, rather than ICE power, which is not producing useful power during breaking.

The engine doesn't make any useful power after it is broken either.

[Bence]

I'm cryin'...