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Discussion Starter #1 (Edited)
Does anybody have any information about this motor? A specs sheet of some sort?
Is it the same or similar to the Tesla? All I can find so far is that it is a 200hp motor. They used two and their system implements an on board generator. Getting one today, fingers crossed... got it. Weighs around 120 lbs. I'll measure when I get it home. Now, what do I do with it.
 

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Seen a few on eBay for sale. Name plate says 6000RPM 150kW 665Nm

Made my Jing Jin electric. It’s huge and looks to be 250lbs


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Seen a few on eBay for sale. Name plate says 6000RPM 150kW 665Nm
Interesting. 665 Nm at 6000 RPM would be 417 kW (if I did the math right), so I assume that 6000 RPM is the maximum speed (likely with a couple hundred Nm of torque at that speed), and 665 Nm is the maximum torque (which it can probably maintain to a couple thousand RPM). Not very fast for a modern motor.
 

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They used two and their system implements an on board generator.
When I first read this I wondered if that meant two motors, or one as generator and one as motor (since this vehicle is a plug-in series hybrid); however...
If I had to guess I think it’s 20” dia and 9” wide.
They used two, one for each rear wheel; usually they are mounted in line across the rear of the car, but the Karma has an oddball arrangement with the motors longitudinal (in line down the centreline of the car), one ahead of the axle and one behind it. Given the maximum motor speed, each motor probably drives the axle through a single bevel (or hypoid) pinion and ring gear set. The Wikipedia article says the Karma is
driven by a pair of 120 kW (161 hp) electric motors
and
The Karma's two 201 brake horsepower (204 PS) motors produce 1,300 newton metres (960 lbf⋅ft) of torque, giving the Karma a quoted horsepower of 403 HP.
(These values don't match, so you can follow the source links and decide what to believe; the second set match the placard)
That's a nice setup that gives torque control at the individual wheel level and good power in total (okay, adequate for this massive car), but using these motors it's a lot of weight, and bulky.
 

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Which controller / inverters to use?
It appears that Fisker got the powertrain from Quantum Fuel Systems Technologies, under the brand name "Q-Drive". The Quantum hardware apparently earned a poor reputation for quality. Quantum went bankrupt in 2016, was purchased and now operates as Quantum Fuel Systems, and the EV portion is called Quantum Zero Emissions; they don't offer aftermarket products, but feature a Karma on their website so perhaps they can provide some information.

The two motors almost certainly had separate controllers/inverters in the Karma, so perhaps a single one can be found. Beyond that, you would need an inverter which can handle the motor's current and voltage requirements, with a controller that can be programmed to handle it... which might be tough for an oddball motor.
 

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Discussion Starter #9 (Edited)
Thanks for all the replies. That's a bit more info than I started with.
I measured it, somewhat. From weld to weld on the outer housing, the motor measured aprox. 5 inches while the diameter is close to 15 inches. It is water cooled so the housing adds another 2 inches to the width and maybe another inch to the diameter measurement. I can deadlift this thing and it feels about 120-125lbs. I'm almost too old to keep lifting my own weight like that, LOL.

Added more pics to original post. I'll weigh it soon.
 

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Good to hear it’s much better than my estimates. Throw that thing on a bathroom scale and let us know what it weighs. I’ve always been a fan of high torque motors.


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Discussion Starter #13
What would be involved in turning this motor into a generator instead? I may have to go that route to use it. Maybe get a cheap 4-cylinder car, remove the tire and disc rotor and slap this thing on the CV shaft to build a generator?
I'm just trying to get some use out of it since using for propulsion is not cost effective at this point.
 

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Can you determine what is housed inside the little box on the back? Does it have an encoder, or resolver, or hall sensors that may be used for commutation?

Any 3-phase brushless DC PM motor controller could be used to drive that motor using the commutation sensor. It could also be driven using a sensorless closed loop controller such as found in many AC inverters for driving variable speed motors.

If you want to use it as a generator, you will need a 3-phase rectifier bridge (6 big diodes).

Can you hook up some sort of small motor or even a power drill to slowly turn the Fisker motor shaft, then put a voltmeter or scope across 2 of the motor leads and measure the back emf waveform or voltage. This will give you some info on sizing your generator, or for use as a motor with sensorless CLC.
 

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What would be involved in turning this motor into a generator instead? I may have to go that route to use it. Maybe get a cheap 4-cylinder car, remove the tire and disc rotor and slap this thing on the CV shaft to build a generator?
I'm just trying to get some use out of it since using for propulsion is not cost effective at this point.
If you want to use an automotive engine and one of these motor to build a generator set you don't need the car's transmission. It can run up to at least 6,000 rpm and can handle all of a small engine's torque, so I don't see any reason to put anything but a suitable shaft coupling between the engine and the motor/generator.

Of course, you also need controller to manage the engine, and it's going to produce high voltage 3-phase AC power at a variable frequency (depending on engine speed and number of motor/generator poles). You can rectify and smooth that for high voltage DC, and invert it for AC power... but that's not a cheap inverter. Do you have a use for a large generator set? Keep it DC and you could build a mobile fast charger for stranded EVs. :)
 

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Discussion Starter #17
Can you determine what is housed inside the little box on the back? Does it have an encoder, or resolver, or hall sensors that may be used for commutation?

Any 3-phase brushless DC PM motor controller could be used to drive that motor using the commutation sensor. It could also be driven using a sensorless closed loop controller such as found in many AC inverters for driving variable speed motors.

If you want to use it as a generator, you will need a 3-phase rectifier bridge (6 big diodes).

Can you hook up some sort of small motor or even a power drill to slowly turn the Fisker motor shaft, then put a voltmeter or scope across 2 of the motor leads and measure the back emf waveform or voltage. This will give you some info on sizing your generator, or for use as a motor with sensorless CLC.
Will try to look into this. Maybe it's of some use after all.
 
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