Thermal Energy Recovery System Generator Motor (MGUH)

[WhiteBlue]

Why the clutch or waste gate will be necessary is that the energy stored is not allowed to be charged in the pit lane.

That is irrelevant in my view as turbine excess energy (beyond what the compressor needs) is not regularly stored in the ES. It is usually fed into a DC link to the MGU-K to be used immediately. I do not see a problem to do this in the pit lane. Engine revs will probably be well above the spool up end point so that excess turbine energy will be available.

[riff_raff]

If you have a M/G coupled to the turbo spool, I can't see why a wastegate would be needed. The M/G is a far more precise device for regulating turbine speed than a wastegate is. If the M/G must apply a load to regulate the turbine speed, it would be simple enough to dissipate any excess power using something like a resistor if the power could not be stored. As for using some type of overrun clutch on the turbo spool, I have never seen any clutch of this type that could function at 100K+ rpm.

[ringo]

Riff raff What type of motor do you suggest will be used, and what physical dimensions?

The regs say the turbine may be clutched, i'm feel 100000rpm will be a lot of rotational stress and heat, however i feel by putting in in the regs, the FIA must feel there is some technology out there that can do this.

I hear your point on the turbine and resistors as a power draw, let's see how it goes.
I'm a proponent of the waste gate, at least as a redundancy. Hopefully we get more info on the engines before the season is over.

[Dragonfly]

With those all new engines and compounded systems the risk of something going wrong is high as we have already discussed.
Imagine a situation where the MG-H or even worse - MG-K has a temporary overheating problem and cannot utilize the generated electric energy. A simple and reliable waste gate in this case would save the race for the driver and the team without the need to put the ICE in some emergency mode of operation.

[WhiteBlue]

That sounds like a reasonable idea.

[olefud]

If you have a M/G coupled to the turbo spool, I can't see why a wastegate would be needed. The M/G is a far more precise device for regulating turbine speed than a wastegate is. If the M/G must apply a load to regulate the turbine speed, it would be simple enough to dissipate any excess power using something like a resistor if the power could not be stored. As for using some type of overrun clutch on the turbo spool, I have never seen any clutch of this type that could function at 100K+ rpm.

What about a magneto-rheological clutch sunk, say, to the crankshaft?

[riff_raff]

Riff raff What type of motor do you suggest will be used, and what physical dimensions?

The regs say the turbine may be clutched, i'm feel 100000rpm will be a lot of rotational stress and heat, however i feel by putting in in the regs, the FIA must feel there is some technology out there that can do this.

There are existing commercial M/G designs http://www.eandausa.com/pmMotor.asp that can operate at speeds up to 500krpm. The more difficult task is designing the PEs and motor controls capable of the combined frequency and power levels required.

As for "clutching" the exhaust turbine, there is no mechanical device that I know of that is capable of operating at speeds of >100krpm. But it is quite feasible to use the M/G controls to unload the turbine.

[ringo]

Frequency of a synchronous machine = rotational speed * number of poles/ 120

I'm not sure how 100,000 rpm will relate to what frequency the teams use, but it's clearly going to be very high.
Details such as number of phases, and also cooling requirements for such a high power high speed machine is also interesting.

From the above it's clear the MG controller will be manipulating the frequency when the machine is in motor mode.

rotational speed = Frequency of a synchronous machine *120/ number of poles

It will be interesting how the turbine inverter controller or whatever the heck they call it will be mapped with driver pedal position, initial turbine speed, exhaust temp, pressure etc. to determine how much to accelerate the MGUH.
Sounds like the meat of the research in the power package.

[wuzak]

Frequency of a synchronous machine = rotational speed * number of poles/ 120

I'm not sure how 100,000 rpm will relate to what frequency the teams use, but it's clearly going to be very high.

Thye can use reduction gearing for the MGUH....

[ringo]

They could, but looking at gear efficiencies, i think they will keep it fully electric. Gears will add quite a bit of inertia to the turbine.
I think most of the systems on the car will run on direct current and maybe you would want to retain that high frequency and also high phase orders.
That MGUH may just have a crazy number of phases like 6 or 12. Normal industries use 3 phases, but it's quite likely the motor will have many more. Rectifying 12 phases to DC should be beneficial as well, as the power carrying capacity is increased but the current losses held low.

have a look at this 17 phase motor:
http://www.chorusmotors.com/exec_summary.shtml
http://www.chorusmotors.com/demo/index.demo.html

a nice article of multiphase motor design:
http://www.jpier.org/PIER/pier131/04.12060507.pdf

[Scotracer]

Has anyone quantified the amount of energy they will be able to recover from the MGU-H? Clearly a wastegate is wasted energy from combustion but have we got some idea how many kW the engines might be able to recover at say Vmax?

[Blackout]

Has anyone quantified the amount of energy they will be able to recover from the MGU-H? Clearly a wastegate is wasted energy from combustion but have we got some idea how many kW the engines might be able to recover at say Vmax?

We've talked about this in the Engine thread. Magneti Marelli's MGUH rototype produces 90kw/120hp atleast.

[Scotracer]

Has anyone quantified the amount of energy they will be able to recover from the MGU-H? Clearly a wastegate is wasted energy from combustion but have we got some idea how many kW the engines might be able to recover at say Vmax?

We've talked about this in the Engine thread. Magneti Marelli's MGUH rototype produces 90kw/120hp atleast.

Right but we aren't going to be extracting 90kW from an exhaust flow simply through the action of stopping the turbine overspeeding. Is it 5kW? 10kW? 1kW?

[dren]

We, mainly TC from some old aircraft engine papers, talked about what % is "free" energy from compounding, and then robbing crank power and transfering it through the MGUH->MGUK since it may be more efficient.

The overrun % was 7% to 15% or so if I remember? And then anything over that was transfering crank power to the MGUK, hence the 90kw motors.

http://www.f1technical.net/forum/viewto ... start=3840

[ringo]

Since the picture of the Mercedes engine has surfaced with what seems to be the compressor of the turbine at the front of the engine.
I have started to wonder if the MGUH motor is actually between the cylinder heads like the Renault unit.
Also, if it is as long as the engine.

It is quite possible that the motor is of the axial design type with a long stator and rotor. The compressor shaft may also be carbon fiber as well bonded to metal and the motor could be jacketed and water cooled.