MGU-K info

[armyk]

Hi guys, does anybody has some info/link about MGU-K?
I want to know which motor they are using, is it squirrel cage? More detailed info is the best!

[Tim.Wright]

I think they are brush-less DC motors:
http://en.wikipedia.org/wiki/Brushless_ ... tric_motor

[armyk]

Eff. should be problem for any of them. it is around 95% for both of them, isnt it?

[pastaracing]

Yo can buy one from McLaren if You want

http://www.mclarenelectronics.com/Produ ... ct/E-Motor

I'm not sure that this is exacly the same as the MGUK in their F1 but close.

[armyk]

Thank you guys, I am sure now that it is permanent magnet synchronous motor.

[Skippon]

This can't be their f1 one.
The 2014 one is part of Mercedes HPP engine package.....
and it wouldn't be 2015 either as that is still prototype with Honda/Zytek.

[marcush.]

http://www.magnetimarelli.com/business_ ... ences/kers
http://thewptformula.com/2014/03/26/ana ... tem-mgu-k/

I ´d think most teams really do not repect just how important it is to keep such systems safely away from excessive heat exposure at all circumstances (heat soak conditions for example).In no time some components degrade in no time towards being unreliable and sudden failures occur.
you just cannot rely on a few temperture stickers to have any idea what is going on dynamically under your bonnet....even IF your max temperature is not exceeded you will not know for just how long certain temps were present ...As a rule of thumb
in electronics one say for every 10degrees of temperature rise you are halving the component life.If you cross the absolute limits -the components will fail instantly..
Maybe some bells are ringing here ...a failure in the last race could well stem from a too high average temperature exposure profile the component experienced much earlier that season ...the resulting failure is a can not a must fail scenario...

[Tommy Cookers]

induction machines have a lot of inductance
inductance is an enemy of responsiveness or responsiveness without instability (for general purposes low responsiveness is desirable)
ie we want the electromagnetic time constant to be much smaller than the electromechanical time constant
this demands a permanent (magnet) field
presumably a rapid modulation of the mgu-k behaviour is required during gearshifts etc

in racing the PU rpm range is quite limited, so anyway ideal for using a PM field

in principle the so-called brushless dc machine and the synchronous machine differ only in the detail of armature (back emf) waveform


@ marcush
we also need to avoid premature ie inappropriate shutdowns of our electrical system by regulatory devices
such a mistaken shutdown (of the engine) cost the gas-turbine Lotus the Indy 500

[Vortex37]

I think (almost certain) that current MGU are switched reluctance type motors. In particular the PPMT type. These give a major advantage, in that they operate in an 'attraction mode', which provides substantially more power density. A 6" diameter x 6" can easily produce 12kw. There are some other inherent advantages, for these motor types, depending on how the FIA would interpret the rules. Better leave that hornets nest, for another day. Easy to see where Mercedes get some of their advantage, (if) they also use this type in MGU-H.

http://dropcanvas.com/87g4e PPMT white paper.

[wuzak]

I think they are brush-less DC motors:
http://en.wikipedia.org/wiki/Brushless_ ... tric_motor

I don't think they are DC motors. Quite sure that they are 3 phase AC motors.

[langwadt]

I think they are brush-less DC motors:
http://en.wikipedia.org/wiki/Brushless_ ... tric_motor

I don't think they are DC motors. Quite sure that they are 3 phase AC motors.

A brushless DC motor is really a three phase motor, the three phase "AC" is just generated from DC by electronics instead of
brushes and a commutator

as soon as you put a variable frequency drive on an AC motor is it bassically the same thing

[Brian Coat]

"There are some other inherent advantages, for these motor types, depending on how the FIA would interpret the rules."

Do you mean "passive" pseudo traction control?

[Vortex37]

"There are some other inherent advantages, for these motor types, depending on how the FIA would interpret the rules."

Do you mean "passive" pseudo traction control?

Yes Brian. All in the local motor control software. FIA won't even discuss it, I've tried. So much for last seasons expression of worry, about tyres being shredded in a couple of laps by these new PU's. I think we both know which engine manufacturer has the best implementation.

[dren]

From the White Paper:

In a PPMT motor the current in the stator field coil increases under load but at the same time provides an induced
bucking flux to reduce the motors retard force. Unlike a conventional VRM the back emf (BEMF) is generated by
the magnet flux switching back and forth through the field coil during rotation. The result is a generator action
internal to the motor that provides an additional energy source from the switching magnet flux to augment the
energy coming from the power supply. A PPMT motor will display an over-voltage condition at the output of the
power supply that will back bias the power supply rectification diodes and prevent power supply conduction
during the over-voltage condition. In other words, even when being driven as a motor, a PPMT device is also
simultaneously acting as a generator for part of each switching cycle. Proper design allows one to thus improve
motor efficiency compared to conventional motors by optimizing the operating point to make maximum use of the
switched magnet flux. Essentially the motor uses the combined flux from the load-induced current added to the
magnet flux to generate shaft torque. Similar benefits occur in applying the motor as a generator. In contrast a
conventional VRM has its BEMF generated by the change in inductance with rotation angle as the rotor passes
over the wound pole and does not have the same potential for increasing efficiency and torque.

[Tommy Cookers]

I think (almost certain) that current MGU are switched reluctance type motors. In particular the PPMT type. These give a major advantage, in that they operate in an 'attraction mode', which provides substantially more power density. A 6" diameter x 6" can easily produce 12kw. There are some other inherent advantages, for these motor types, depending on how the FIA would interpret the rules. Better leave that hornets nest, for another day. Easy to see where Mercedes get some of their advantage, (if) they also use this type in MGU-H.

http://dropcanvas.com/87g4e PPMT white paper.

why would we think that this type of machine/drive combo are as efficient as a suitable synchronous machine ?
(yes, I have read the previous post)
autogyro iirc posted some very impressive synchronous efficiency/performance plots some time ago

and surely there's no mystery about 'Y.K.W' ?
any system regardless of the type of electrical machine will need to be and will be stable by design
this stability (ie falling/reversing torque with unplanned rapid rpm rise, as in wheelspin) is what (legally) emulates traction control
not so different from the long-established 2d mapping from accelerator pedal to throttle plates