hub with 6 phase wires

Where do you live that you would rather rewind the motor (lol) than just get two controllers?
 
Addy said:
minde28383 said:
Can somebody explain me why two motors won't work if both 3 phase motors are on the same stator? And of course phase sequence is the same.
Do you now somebody trying to run such motor with one controller unsuccessful or successfully? Do you really know that it won't work?
I think it must work with one 3 phase controller.
Click to expand...

Two motors can work together if their rotors are physically locked together and the electrical phases are exactly aligned. From what everyone is saying, it seems like the phases in your motor are not aligned. This is logical. Why would the manufacturer choose a 6 phase wiring setup if it would be easier to do a 3 phase winding? They have offset the phases for smoother torque delivery.
Click to expand...

Hi Addy,
My assumption is because manufacture would want to save energy and/or double power when needed thus having two motors inside one. When needed, both 3 phase motors kicks in, and when power is needed less then one 3 phase motor becomes idle. Idle motor drag can be canceled by controller. Nevertheless, if that's the case than phases could be aligned or be misaligned.


Now back to my belief that the hub (two 3 phase motors on one stator) must be able to run with only one 3 phase controller.
Lets assume that phases are offset, but we don't know it yet, but lets assume it.
Why two 3 phase motors on the same stator can't be driven by one 3 phase controller? Does anybody truly understands it and can explain?
 
Do you understand what is meant by timing? It means the two sets of windings are not in position to drive the right magnets at the same time. That's the issue.
 
minde28383 said:
Hi Addy,
My assumption is because manufacture would want to save energy and/or double power when needed thus having two motors inside one. When needed, both 3 phase motors kicks in, and when power is needed less then one 3 phase motor becomes idle. Idle motor drag can be canceled by controller.
Click to expand...
This is not necessary. A 3 phase motor could simply be driven with less current/power if you are trying to save energy - I don't think there would be much benefit to have separate windings for this. It is significantly more work to manufacture it with 6 phases and 6 wires.


minde28383 said:
Lets assume that phases are offset, but we don't know it yet, but lets assume it.
Why two 3 phase motors on the same stator can't be driven by one 3 phase controller? Does anybody truly understands it and can explain?
Click to expand...
If the phases are offset, if you tried to drive two offset phases at the same time, each phase would be pulling the magnets to a different place. They would be fighting each other. At best the motor would be very inefficient, if it even could spin at all.
 
Addy said:
minde28383 said:
Lets assume that phases are offset, but we don't know it yet, but lets assume it.
Why two 3 phase motors on the same stator can't be driven by one 3 phase controller? Does anybody truly understands it and can explain?
Click to expand...
If the phases are offset, if you tried to drive two offset phases at the same time, each phase would be pulling the magnets to a different place. They would be fighting each other. At best the motor would be very inefficient, if it even could spin at all.
Click to expand...

"pulling the magnets to a different place"
Isn't it the whole idea of making movement.
If phases are one after another then it will drive forward, not fight. Why phases would fight each other. Don't know about efficiency, this is a whole other topic, but according my understanding the hub should run good with one 3 phase controller.
 
Did little test but I doubt if this test can be trusted determining phase firing times.
At the beginning I thought that bulbs can show phase start times but now I think that if phase angle would be off by 30 and you still won't see difference looking to bulb turning ON/OFF.
Nevertheless both bulbs fire ON exactly at the same time.
 
minde28383 said:
"pulling the magnets to a different place"
Isn't it the whole idea of making movement.
If phases are one after another then it will drive forward, not fight. Why phases would fight each other. Don't know about efficiency, this is a whole other topic, but according my understanding the hub should run good with one 3 phase controller.
Click to expand...

Pulling the magnets to a different place at a different time would make the motor spin. Pulling them to a different place at the same time would accomplish nothing except wasting energy.

Your understanding is incorrect, as everyone is trying to tell you. If you're so sure that we're all wrong and that you understand brushless motor commutation, do an experiment with your motor. Drive it with a 3-phase controller, with your double phases wired in parallel. Let us know how well that works.
 
minde28383 said:
Did little test but I doubt if this test can be trusted determining phase firing times.
At the beginning I thought that bulbs can show phase start times but now I think that if phase angle would be off by 30 and you still won't see difference looking to bulb turning ON/OFF.
Nevertheless both bulbs fire ON exactly at the same time.
Click to expand...
 

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Yes. Just plug them both into the controller. I don't understand why you still haven't tried this. A bad config WILL NOT blow the controller with a brief test at partial throttle. Do you not believe this? People here might do essentially the same thing several times as they try different phase combos in a motor with unknown phase / hall position. You will know immediately if the motor works.
 
Addy said:
minde28383 said:
"pulling the magnets to a different place"
Isn't it the whole idea of making movement.
If phases are one after another then it will drive forward, not fight. Why phases would fight each other. Don't know about efficiency, this is a whole other topic, but according my understanding the hub should run good with one 3 phase controller.
Click to expand...

Pulling the magnets to a different place at a different time would make the motor spin. Pulling them to a different place at the same time would accomplish nothing except wasting energy.

Your understanding is incorrect, as everyone is trying to tell you. If you're so sure that we're all wrong and that you understand brushless motor commutation, do an experiment with your motor. Drive it with a 3-phase controller, with your double phases wired in parallel. Let us know how well that works.
Click to expand...

There are some here who would agree that hub with two 3 phase motors in it would work with 3 phase controller with condition that phases are of the same timing. Indeed, initially I was not aware that my two 3 phases motors might have different timing. And still don't know its timing, oscillograph would answer that for sure. Lately that was of the the things I was trying to find out therefore no luck yet. Some advices contradict each other. Elsewhere I'm adviced that it must run good even with different timing.
 
minde28383 said:
minde28383 said:
Did little test but I doubt if this test can be trusted determining phase firing times.
At the beginning I thought that bulbs can show phase start times but now I think that if phase angle would be off by 30 and you still won't see difference looking to bulb turning ON/OFF.
Nevertheless both bulbs fire ON exactly at the same time.
Click to expand...
Click to expand...

What about this experiment. Does it reveal phase timing?
 
Since the answer to your question is staring you in the face let me just quote my last unacknowledged post.

flat tire said:
Yes. Just plug them both into the controller. I don't understand why you still haven't tried this. A bad config WILL NOT blow the controller with a brief test at partial throttle. Do you not believe this? People here might do essentially the same thing several times as they try different phase combos in a motor with unknown phase / hall position. You will know immediately if the motor works.
Click to expand...
 
Alan B said:
Here's the for sale thread for a motor like this:

https://endless-sphere.com/forums/viewtopic.php?f=31&t=46898

The seller might have some advice for you.

Rewinding a hubmotor is a lot of work and there are many mistakes that can be made. There are threads here on doing that.
Click to expand...

This is very interesting topic you found. That's what I needed. I though nobody else have such hub.
 
flat tire said:
Since the answer to your question is staring you in the face let me just quote my last unacknowledged post.

flat tire said:
Yes. Just plug them both into the controller. I don't understand why you still haven't tried this. A bad config WILL NOT blow the controller with a brief test at partial throttle. Do you not believe this? People here might do essentially the same thing several times as they try different phase combos in a motor with unknown phase / hall position. You will know immediately if the motor works.
Click to expand...
Click to expand...

It's better to check and ask than later to be sorry. It's good that Sabvoton has various protections and does allow to destroy it so easy.
Finally I connected all 6 wires to 3 phase controller by splitting wire and can't even do hall test as controller shows system error - over current.

yellow1,yellow2 (motor) - yellow (controller)
blue1,blue2 (motor) - blue (controller)
green1, green2 (motor) - green (controller)

I don't want to rewind hub after seeing Alan's post about these hubs. Looks like it's nice little hub but needs second controller as you guys suspected. Good thing is that it does not need to be synched as some of you though because cheap controllers does not work as master slave.

And I thank you all for advices very much and even more considering how stubborn I was about that it should work with the 3 phase controller.

So overall I believe it's all clear now, - either acquiring second controller or selling scooter and/or hub.
 

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Glad you came to your senses! I have one of these motors, they're incredibly good compared to most other hubs. Two Sabvotons or Kelly controllers and you can pretty easily run 20kw.
 
flat tire said:
Where do you live that you would rather rewind the motor (lol) than just get two controllers?
Click to expand...

I overlooked this post yesterday.
I don't mind but why you ask? Is it very expensive procedure at your place or it's not about price?
People are rewinding coils for years for living. Either I do it myself or ask somebody to do it for me.
Acquaintance of mine did it successfully the very first time.
But after so much I found about his motor I do not plan to do it anymore.
 
Alan B said:
One of the advantages of the six pole motor is the reduced need for sinewaves, due to the overlapping three phases the ripple is considerably reduced even with trapezoidal controllers.
Click to expand...

It is very interesting point I had never heard or thought about it before.
These mid powerfull trapolized controllers are about 100usd each and 100 shipping so 300usd overall without VAT.

So for me it's either speding 300usd for two trapolized or getting second Sabvoton for also 300usd.
 
minde28383 said:
Alan B said:
One of the advantages of the six pole motor is the reduced need for sinewaves, due to the overlapping three phases the ripple is considerably reduced even with trapezoidal controllers.
Click to expand...

It is very interesting point I had never heard or thought about it before. I mean - ... six phase, overlapping, ripple, reduced need for sinewaves...
These mid powerfull trapolized controllers are about 100usd each and 100 shipping so 300usd overall without VAT.

So for me it's either speding 300usd for two trapolized or getting second Sabvoton for also 300usd.
Click to expand...
 
minde28383 said:
If phases are one after another then it will drive forward, not fight. Why phases would fight each other. Don't know about efficiency, this is a whole other topic, but according my understanding the hub should run good with one 3 phase controller.
Click to expand...
Depends on the phase angle difference. If it's 1 degree or something you might not even notice the difference. If it's larger you will see odd effects, including running fast in one direction but slow in another (phase advance/delay) reduction in torque (fields opposing each other) and unusual back-EMF's (could be dangerous for controllers.)
 
Ohbse said:
Glad you came to your senses! I have one of these motors, they're incredibly good compared to most other hubs. Two Sabvotons or Kelly controllers and you can pretty easily run 20kw.
Click to expand...

Hi guys,


20kw is very abstract. Let us talk more about where these 20kw comes from.

Originally scooter was driven by controller which is capable of 100A batt constant (phases Amps unknown), 50A each 3 phase motor.

My 72v battery pack can do 180A constant discharge, peaks well over 300A.

Considering scooter weighs 80kg, rider 85kg. Ps. Keeping high speeds for prolonged time is not the aim. Mostly might do 40MPH and less. If hub stays than I'll add temp sensor, but temperature factor lets leave out of equation for now. I want to get better view of hubs mechanical capability but not thermal limits even two of them are very related.

How Amp settings might look from controllers side?
Do such A settings are on highest side?

First controller - 100A batt / 250A phase; second controller - 100A batt / 250A phase

Constant 2x100A x 72v = 14.4kw
Phase 2x250A x 72v = 36kw


If it is capable to be pumped 2x100A batt / 2x250A phase than it is more capable than QS 3000w V3.
Can you compare such 6 wire hub with QS 3kw v3 hub? I heard QS 3kw v3 can do 150A/350A for peaks.

Your all thoughts appreciated.
 
billvon said:
minde28383 said:
If phases are one after another then it will drive forward, not fight. Why phases would fight each other. Don't know about efficiency, this is a whole other topic, but according my understanding the hub should run good with one 3 phase controller.
Click to expand...
Depends on the phase angle difference. If it's 1 degree or something you might not even notice the difference. If it's larger you will see odd effects, including running fast in one direction but slow in another (phase advance/delay) reduction in torque (fields opposing each other) and unusual back-EMF's (could be dangerous for controllers.)
Click to expand...

This is very much telling explanation. That why some folks were telling me that it is possible to run this hub with 3 phase hubs- due possible slight or no difference in phase angle.

Danger of back-EMF I understand following way. Current is pushed to one phase but in the mean time another phase from another 3 phase motor is working as generator and generating electricity. Because controller is meant to work with three phase it might not block (gates open) current generated fed back to controller and possible have negative effect on controller itself?
But somewhy Sabvoton did not even allowed to perform such experiment.

So neither I noticed odd effect nor it ran at all. And does it has anything to do with phase angles. Can sobedy explain why it might had happen?
A hint. Two 3 phase motors are winded differently. One - start, another - delta?
 
minde28383 said:
Danger of back-EMF I understand following way. Current is pushed to one phase but in the mean time another phase from another 3 phase motor is working as generator and generating electricity. Because controller is meant to work with three phase it might not block (gates open) current generated fed back to controller and possible have negative effect on controller itself?
Click to expand...
Again depends on phase angle.

If the electrical phase angle difference is small - and all the phases are connected together - all you will see is an unexpectedly higher or lower EMF (probably manifesting itself as a different motor constant, again depending on which direction it was running.) If the difference is larger you'll see currents start to actively oppose each other for parts of the phase drive time.

Think about it this way. If you drove one stator and the second stator was disconnected and was in phase (zero offset) then you would see voltages coming out of the second stator very similar to what you were feeding into the motor (minus losses.) So if you connected them together it would work about the same.

But if you drove one stator and the second stator was disconnected and was out of phase (say 15 degrees or so) then you would see voltages coming out of the second stator quite different to what you were feeding into the motor. So if you connected them together there would be times the fields would "agree" (i.e. current in generates forward torque) and there are times when the fields would "disagree" (i.e. current in generates forward torque in one stator, reverse torque in the other.) That also means that the back-EMF will look strange, as if you are commutating at the wrong time in the cycle.

So neither I noticed odd effect nor it ran at all. And does it has anything to do with phase angles. Can sobedy explain why it might had happen?
A hint. Two 3 phase motors are winded differently. One - start, another - delta?
Click to expand...
That seems VERY unlikely. The most likely explanation is that their topology is the same, they are just phased differently. (Note - delta wound motors have two magnet wires, or sets of magnet wires, terminating in each phase wire. No other connections. Wye wound have a big "central connection" point with one magnet wire, or one set of magnet wires, terminating in each phase wire.)

Here's an experiment you might try. I assume this motor has Hall sensors, right? Move the Hall sensors around so that a "compromise" position is reached; an average between the two phases. The motor would likely run, albeit with much lower efficiency and odd torque characteristics.
 
billvon said:
Here's an experiment you might try. I assume this motor has Hall sensors, right? Move the Hall sensors around so that a "compromise" position is reached; an average between the two phases. The motor would likely run, albeit with much lower efficiency and odd torque characteristics.
Click to expand...

It does have halls, Actually two sets of them. Earlier controller passed hall test numeriuos times sucesfully when connected with only one 3 phase motor or another one 3 phase motor. In other words hall test passed sucesfully when only one 3 phase motor was used at a time.

Controller can't go beynd "over current" error when both 3 phase motors / 6 wires are connected to controller. Controller sees something is wrong and does not put controller into running state. Moving hall sensors around won't make and effect.
 
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