QS 3000w midmotor

[PITMIX]

I confirm that the assembly of the pinion with the Woodruff wrench is very strong and no problem. My friend who destroyed his motor shaft had a new shaft supplied by Qs motor.

 

[Jagrkid2186]

Hey still new to electric motors so any input is appreciated. I have a QS 138 3000w motor, Id like to increase the power to ~5000w. Would doing that be as easy as increasing the amps from the controller or is there more to this than I’m understanding?

Thank you!

 

[j bjork]

The spec says 470pA I think. It can probably take more, but about 500A goes a long way. You can probably run 5kw continuous more or less, just make sure that your controller or you have control of the temp. It takes at least 25kw peak without problem.

 

[Jagrkid2186]

That’s great advice, thank you. By any chance would you happen to know how many amps I’d need to push to the motor to get 5kw out of it? It’s currently at 72v. Once again, I may be asking the wrong question so please feel free to correct my thinking.

 

[eee291]

simple, 5000w/72V=69.44A which is pretty weak IMO.
I'm running it with 450A phase and 250A Battery, I can't even get the motor to get hot with repeated launches and hard acceleration

 

[Jagrkid2186]

Sounds awesome! Thanks for the quick response. Is it really that straightforward or do you need to over estimate amps? Like if I push 100 amps on a 72v current do I really get 7,200w? Or does some of the power get lost to friction?

 

[john61ct]

Current is what it is, at the specific point you measure it.

power watts & amps current get pulled, not pushed.

When voltage is fluctuating all over the place, which it is between the controller and inside the motor, best to stick to Watts power units.

So long as heat is not allowed to destroy the motor, and the other parts can handle delivering Moar!

 

[eee291]

Well of course you lose power due to friction in the motor and drive train, and not to forget electrical losses inside the motor (eddy currents).
There's also a certain rpm range where the motor runs most efficient, if it's outside that range the motor will convert a ton of energy into heat.

 

[PITMIX]

To warm up this engine you really have to ask a lot of it. At 25kW peak on a 400kg vehicle with strong acceleration and high speed for several long minutes, from repeated stops and starts.The engine does not heat up even if it is hot outside.

 

[john61ct]

Which is of course a Very Good Thing!

Let me know if the below makes sense, assuming a powerful FOC controller, say Nucular 24F.

What voltage will give a top speed under 28mph with a 25" outer diameter?

Then which of the windings offered by QS will give best efficiency at ~20-22 mph?

I'm assuming the resulting torque availability will be good for hill climbing with heavy loads, even without gearing?

 

[j bjork]

Which is of course a Very Good Thing!

Let me know if the below makes sense, assuming a powerful FOC controller, say Nucular 24F.

What voltage will give a top speed under 28mph with a 25" outer diameter?

It depends on the gearing.

Then which of the windings offered by QS will give best efficiency at ~20-22 mph?

I think there are just one winding. But it doesent really matter, just choose the right gearing.

I'm assuming the resulting torque availability will be good for hill climbing with heavy loads, even without gearing?

What do you mean without gearing? 1:1 gearing? That would be a bad idea in most cases

 

[john61ct]

I'm trying to get a handle on Kv/winding vs pack voltage issues

thus eliminating gearing for simplification, even if just a thought experiment.

But also (just curious), isn't there an equivalent DD hub motor version of this unit?

 

[eee291]

I'm trying to get a handle on Kv/winding vs pack voltage issues

thus eliminating gearing for simplification, even if just a thought experiment.

But also (just curious), isn't there an equivalent DD hub motor version of this unit?

QS 205 50H for ebikes, for motorcycles they have some up to 14Kw cont.

 

[j bjork]

This is a IPM inrunner with a kv about 60
That is 6000rpm at 100v

Hubs are outrunners with kv around 10. (the different kv:s probably starts around 5 and goes up to around 20)
That is 1000rpm at 100v

 

[john61ct]

How does this one compare to the Cyclone 3K, for torque grunt at low speeds?

 

[eee291]

How does this one compare to the Cyclone 3K, for torque grunt at low speeds?

I'm pretty sure the cyclone uses a planetary gear set inside the casing, but if we compare purely motor shaft torque then the QS always wins, I don't think the cyclone can handle 25kw peaks.

Note that by comparing the cyclone with the qs you may be underestimating the size and weight of the QS 3K.
For a ebkie you might want to go with a smaller mid drive motor like the QS 2K or a Hub.

https://www.alibaba.com/product-detail/QS-Motor-New-Launched-Product-120_62089718779.html

 

[john61ct]

Use case is heavily loaded tandem/cargo slowly climbing long steep mountain "roads".

Just the battery pack might be 100lbs, might need multiple motors.

 

[eee291]

I'm pretty sure the QS 3K is enough to pull a small car, you just need proper gearing that's all.

 

[PITMIX]

Just watch my videos to understand that this is possible very easily with an 8: 1 reduction gear.
I even tested 9,3: 1.
you can select the subtitles in English
https://youtu.be/FHrRvNgXyIw

 

[SmartStupid]

Any updates on the new 138 motor with the reduction drive? I have pre ordered this motor and am looking for some clarity. An earlier post in this thread mentioned that this motor comes with a 20mm shaft, to my knowledge this is false. I have both 2D drawings directly from cnqsmotor and a 3D file that they sent me which I have viewed in inventor. The shaft has a 14mm inner diameter and a 17mm outer diameter. This is starting to concern me as the shaft size has decreased from past versions of the motor and will experience more torque due to the reduction drive. Not only that but there are absolutely no sprockets for a 520 chain that are compatible with those shaft dimensions. That being said I have to buy a blank sprocket with a small enough bore to have the tooth pattern custom cut. The only viable sprockets for this operation that I have found are $32.00 a pop .

 

[NitramT]

Does anyone have any experience with Kelly or QS motor controllers ? Any specific reason why one or another is better with this specific drive ? Or any other controller that works good for You ?

Bit confused which one should I choose.

 

[minde28383]

Any updates on the new 138 motor with the reduction drive? I have pre ordered this motor and am looking for some clarity. An earlier post in this thread mentioned that this motor comes with a 20mm shaft, to my knowledge this is false. I have both 2D drawings directly from cnqsmotor and a 3D file that they sent me which I have viewed in inventor. The shaft has a 14mm inner diameter and a 17mm outer diameter. This is starting to concern me as the shaft size has decreased from past versions of the motor and will experience more torque due to the reduction drive. Not only that but there are absolutely no sprockets for a 520 chain that are compatible with those shaft dimensions. That being said I have to buy a blank sprocket with a small enough bore to have the tooth pattern custom cut. The only viable sprockets for this operation that I have found are $32.00 a pop .

Your concern is that 520 standard front sprocket is not readily accessible. I have this and another concern.

Some time ago I saw drawing of this motor and it had 17mm 14mm shaft. I was also interested to find out why not 20mm.
If 17mm/14mm will keep having have issues (brake) I'm sure it will be changed to 20mm.

 

[minde28383]

Does anyone have any experience with Kelly or QS motor controllers ? Any specific reason why one or another is better with this specific drive ? Or any other controller that works good for You ?

Bit confused which one should I choose.

People are running this motor with various controllers. Votol, Kelly, Nucular. Some good and expensive controllers might be complicated to configure. As long as controller is smart, configurable and supports high rpm motors it can be set. If want cheap get Votol. All three will work with the motor. If looking for specific controller model number - google or look in the forum. Nucular is most advanced of these three. If don't care too much about latest and greatest than get any. People have issues sometimes setting Votol but at the end it works out.
In size and weight, bigger to smaller: Kelly Votol Nucular
In price, bigger to smaller: Nucular Kelly Votol
Other controllers will work but might have some limitations or be not so smooth and / or be not able to reach max rpms if not designed to high rpm motor or be less efficient for such kind motors like this one.

 

[phaseshift]

Any info on the V4 yet? Considering it or a Motenergy motor for an electric drift kart. Not looking for speed, just torque. 84-96V planned voltage 60AH 10C cells. Anyone running 500A+ ESCs on 96V?

 

[ZERONEST]

I confirm that the assembly of the pinion with the Woodruff wrench is very strong and no problem. My friend who destroyed his motor shaft had a new shaft supplied by Qs motor.

Did your friend fit the shaft himself? And did Qs cover it under the warranty? I had seen a video of someone who had purchased a motor and was supplied with both splined and keyed shafts