Author Topic: New electric motor does away with gearboxes  (Read 171 times)

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Offline Laconian

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New electric motor does away with gearboxes
« on: August 10, 2019, 02:27:15 pm »
https://newatlas.com/linear-labs-hunstable-electric-motor/60974/

It sounds like it has an EV equivalent of VVT, where it can phase a subset of its four rotors to reduce the strength of the magnetic field. It trades torque for higher RPMs, which makes it possible for the motor to run in a direct drive configuration, with no need for a reduction gear. Low RPM acceleration is smoother too, since it can produce overlapping power that smooth out the otherwise loping torque curves.
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Offline Laconian

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Re: New electric motor does away with gearboxes
« Reply #1 on: August 10, 2019, 02:28:21 pm »
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Offline NomisR

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Re: New electric motor does away with gearboxes
« Reply #2 on: August 10, 2019, 02:35:47 pm »
EV has real gear boxes?  I thought it was just reversing the polarity.

Offline Laconian

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Re: New electric motor does away with gearboxes
« Reply #3 on: August 12, 2019, 08:19:43 pm »
Yup, your Bolt has a 7:1 reduction gear.
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Offline Eye of the Tiger

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Re: New electric motor does away with gearboxes
« Reply #4 on: August 12, 2019, 08:35:46 pm »
Yup, your Bolt has a 7:1 reduction gear.

Spark EV only has 3.87:1 gear, which makes the 327 lb-ft torque rating less impressive.
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Online Soup DeVille

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Re: New electric motor does away with gearboxes
« Reply #5 on: August 12, 2019, 08:46:50 pm »
EV has real gear boxes?  I thought it was just reversing the polarity.

Yes, but the losses from a simple reduction gear box are minimal. This motor seems to be a sort of compound-stator stepper motor (that is, there's a rotor with another stator inside it and a secondary rotor inside that "rotating stator," and that one's a multi-phase stepper motor instead of a permanent magnet DC motor.

Clever, but I wonder when all the numbers are crunched, how much better it really is than a modern AC stepper
motor and reduction gearbox
We should get into the sympathy business.  There is a killing to be made.

Offline afty

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Re: New electric motor does away with gearboxes
« Reply #6 on: August 13, 2019, 08:31:42 pm »
The Taycan will have a 2-speed gearbox.

Online Morris Minor

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Re: New electric motor does away with gearboxes
« Reply #7 on: August 16, 2019, 11:36:37 am »
Can someone explain to this non-electrical engineer the basics of the no-DC-DC-converter-thingy-needed reference?
My understanding was that in EVs, DC battery power is goes through an inverter to give some representation of sine wave-type juice to the AC traction motors.
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Offline Laconian

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Re: New electric motor does away with gearboxes
« Reply #8 on: August 16, 2019, 12:44:57 pm »
The Taycan will have a 2-speed gearbox.

It seems like a mandatory bit of kit for an Autobahn stormer. That's a very wide range of speeds.
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