Maximilian Guettinger

Trying to do the right thing. Advancing the world of atoms. Good things take some time! @emil_motors

[Maximilian Guettinger @GuettingerMax]

@mil000 Just good taste

[Maximilian Guettinger @GuettingerMax]

I’m seeing so many people in the US realize how important manufacturing, machining and engineering is. It’s been outsourced for decades and now it’s becoming obvious that manufacturing is the basis of everything and you don’t want to depend on potential adversaries for that. Germany, are you listening? We have all that stuff right now and are doing nothing to preserve it. German industry is going through the toughest time and it’s not looking good for the future. High electricity cost, taxes and regulations are ruining this country and most people don’t even realize what we have today. Our industry is an asset

[Maximilian Guettinger @GuettingerMax]

Summary and what this means:
You can use high harmonic windings because the airgap velocities are usually much lower which leads to overall lower AC losses even with significant harmonics and you can thus also use higher pole counts which have higher fundamental frequencies.
This explains why concentrated windings are favored for small machines. They have very short end windings, are easy and cheap to manufacture and result in high pole counts (which makes the magnetic yoke smaller and the machine more torque dense). For a machine which focuses on a more torquey design and not full high speed, this is ideal. Of course if this machine were to be pushed to the airgap velocities of an F1 motor, it would produce losses like crazy and be unusable.
The next major issue is magnetization. As mentioned the ratio of magnetization effort to actual torque creation is worse in small machines because the airgap length cannot decrease indefinitely. This makes magnetless small actuators or motors inherently less performant. They tend to go for lower pole counts to reduce the magnetization effort somewhat which increases their weight and makes them less power dense. In addition they are much lossier because they have to come up with all that magnetization effort with winding currents which create heat.
Permanent magnets offer an attractive fix. If you have a hard problem shoot it with a shotgun. Small motors use a lot of magnet material per Nm of torque due to these inherent drawbacks. But with so much rare earth they keep all the other parts of the motor compact and lightweight while also not causing any losses to achieve their magnetization. It might not seem elegant, but for small electric motors this is the only solution today. As we are focusing on magnetless performance motors at @emil_motors, I have thought long and hard about high performance small magnetless designs. It’s very difficult and so far I’m not happy with any solution I could come up with. For electric vehicle sized motors it’s much easier and actually quite shocking that we still use so much rare earth material. It really isn’t needed

Thanks for reading to the end
Max

[Maximilian Guettinger @GuettingerMax]

Let’s talk about why optimized electric motor designs change so much when going from large power dense machines to small machines. Say for example doing from a high speed turbo generator in a modern turbine plant to an electric vehicle motor to an e-bike or drone motor.

All of these machines have vastly different motor designs because the physics change much more than you would naively assume.
There are three major factors which push motor designs here. One is airgap velocity, the other is the airgap length to flux path length ratio and the last one is length to diameter ratio. Let’s break them all down and what that means for concrete motor designs.

[Maximilian Guettinger @GuettingerMax]

Third: length to diameter ratio
Smaller electric motors also tend to have short packaging spaces. As most small machines tend to focus more on torque designs than on fully high speed low torque designs, it makes sense to focus more on higher diameters and make the package nice and small with a short motor length.
This results in a lower length to diameter ratio. For a standard radial flux machine this is not great, because the end winding portion of the winding is always the same size, no matter how long the active part is. The end winding is just loss, no torque production. So you want a low ratio of end winding to overall winding length. When decreasing the machine length and decreasing length to diameter ratio this becomes a very important topic and end windings have to be as small as possible. Then you have a longer active length this does not matter as much because the ratio of end winding to overall winding length drops.

[Maximilian Guettinger @GuettingerMax]

@recreatings Haha, nice one 😂 that little baby ain’t no James Bond

[Maximilian Guettinger @GuettingerMax]

@DHofmann77 @FrankfurtZack 😂👍

[Maximilian Guettinger @GuettingerMax]

Ne, Handy bleibt in der Tasche. Keyless Go würden VAG Liebhaber das nennen. Keine schreckliche App, die 2 Minuten lädt und mir dann sagt, dass der Befehl fehlgeschlagen ist.
Einfach zum Auto hin mit Handy in der Hosentasche, am Türgriff ziehen und das Auto geht auf. So einfach, das können sich die VW Kunden gar nicht vorstellen.

[Maximilian Guettinger @GuettingerMax]

@Elektro_Robin Ok, es wird schnell klar. Deine Posts richten sich ohne Bezug auf Kontext generell gegen Leute, die Fortschritt feiern und damit hinter Tesla stehen. Immer schön stänkern und schlechte Laune verbreiten, immer weiter so

[Maximilian Guettinger @GuettingerMax]

@faznet Klare Worte, Respekt

[Maximilian Guettinger @GuettingerMax]

Man findet immer Gründe, warum man etwas nicht tun sollte oder was noch nicht perfekt funktioniert.
Fakt ist, in allen westlichen Ländern kann FSD mittlerweile nahezu perfekt Auto fahren und es wird immer noch jeden Monat besser. Wenn du “nur” den Auto Markt außerhalb Indiens und Thailands abdeckst, ist das doch ein herausragendes Ergebnis!

[Maximilian Guettinger @GuettingerMax]

@florian_krammer Statistically impossibility claims age poorly. Disruption is much more common in the world than people think. Of course it doesn’t happen every year, so people forget it happens at all

[Maximilian Guettinger @GuettingerMax]

@tzukima 😂

[Robin Engelhardt @Elektro_Robin]

Luftfahrt wird elektrisch. Flugscham können wir uns mittelfristig sparen und statt der komplett dysfunktionalen Bahn einfach wieder mehr Inlandsflüge machen. Die üblichen Technikfeinde werden es wieder doof finden - ich freu mich drauf.

[Maximilian Guettinger @GuettingerMax]

@nicolange_ Genialer Vergleich, der die Absurdität sehr deutlich macht

[Nico Lange @nicolange_]

Die Kosten des Bahnhofs Stuttgart 21 liegen mit 14,5 Mrd. Euro höher als der Aufbau der geopolitisch transformativen Satellitenkonstellation Starlink mit etwa 12 Mrd. Dollar. Stuttgart 21 hat 23 Jahre Bauzeit, der Aufbau von Starlink dauerte 6 Jahre. Keine Pointe.

[Maximilian Guettinger @GuettingerMax]

@Global_Garage_ Tesla Model 3 has higher torsional rigidity than a BMW 3 series, so yeah. It drives very well in corners