Connect a 2 coil stator to 3 phase ESC possible?

[supak111]

Hey guys I have a 2 coil stator/brushless motor with 2 poles (1 magnet 2 sides). Is there any way to connect it to a 3 wire 3 phase electronic speed controller?

I was thinking maybe like this image. Added a diode so phase #2 doesn't spin the motor backwards. Just not sure if the ESC will still work with phase #2 pretty much disabled. And the other problem I see is that now phase #1 will only go across 1 coil, phase #2 disabled, and phase #3 will go across both coils so the torque might be weird...?

 

[Bluejets]

Show motor details/specs

 

[supak111]

Its actually a Dyson digital vacuum cleaner motor, its just a propeller shaft with a neodymium magnet on the end. Dyson says its rated for 200w I think, and they run it off 24v lithium battery. Dyson says it can spin to a 106k rpm. It looks like this now after I stripped everything off of it.

 

[Bluejets]

Cannot see any image.... permanent magnets make me think it's dc, not ac.
Need to see more detail ...

 

[supak111]

This motor use to run off single phase AC. Now I have a 3 phase ESC controller that I would like to use.

 

[duke37]

If the motor is two phase, then the windings are at 90 deg.
A three phase controller will need windings at 60 deg.
The drive is AC and diodes will mess this up.

I do not see your picture.

 

[supak111]

20160302_173127-768x432.jpg

 

[duke37]

Still cannot see the picture, my computer says there is a security problem. Why not just attach the picture?

 

[supak111]

I can see both of them just fine. Here

 

[duke37]

That's better. I cannot work out how the motor works, it seems to have a non contacting magnetic 'commutator' to energise the rotor. There must be another magnet somewhere either electro or permanent to react with this field.

A simple radial fan will work in either direction but it is much more likely that a sophisticated fan is used for efficiency.so there must be a method of setting the direction.

 

[Bluejets]

Looks to me like some form of high frequency induction motor designed to be run from a specific controller.

Wondering why you don't use the original controller.

Re-inventing the wheel to me seems rather pointless.

 

[supak111]

Because I burned it out and I also wanted to run the motor of a 12v battery not the original 24v lithium setup they had. Could not figure out how to run it of another 24v battery, and in the process of trying figure it out I burned out the original single phase ac controller

 

[FrankBolleri]

Hello all,
I finally found someone with exactly my situation.

I am in the exactly same situation (same Dyson motor and original controller burned by my tests) - so I am searching for any suggestion to make it run again.



I will add some info:

The motor come out from a Dyson DC35 Multifloor.

The only permanent magnet is on the shaft of the rotor (made by neodymium):


The stator is composed by two "electromagnets" in which terminals (T1 and T2) are designed to be always in opposition of polarity:


I think that applying DC current both "electromagnets" are always active and always opposite (N/S).

I've tryed to apply an oscilloscope and turn the shaft manually, I obtain this:



So, I suppose that should be enough to provide a sinusoidal AC voltage to make it move, but i am currently searching for a power suplly with enough current...

Meanwhile, someone have some other suggestion?

For example, someone know about some commercial ESC driver for a motor built in that way?

Thanks in advance.
Frank

 

[Minder]

You may not need a sinusoidal, just an AC drive/amp that offers reversal to produce the required RPM, could be a square wave provided by simple Mosfet switcher/drive.
Just as long as polarity reversal occurs.

 

[FrankBolleri]

Hello Minder, thanks for your answer.
I will try with a square signal for first, but before make any experiment I have to wait the arrival of these resistors for trying put it in series



because the motor coil appear to be between 0.08/0.1 ohm (at rest) and my power supply is not able to produce enough current for a direct connection.

I have also purchased this object


seen at https://www.dmcinfo.com/latest-thinking/blog/id/9462/low-cost-function-generator-amplifier-diy
in order to be able to experiment different waveforms directly from signal generator driving my power supply.

So I will update here when I will have done some experiments.

Meanwhile, I have done again the oscilloscope test, acquiring this time the entire short period of the "manual inducted rotation".

Because it appear in that way:


seems to me that there is a linear proportion to mantain between signal frequency and supplied voltage/current.

When I have some news, I will update here.

Frank

P.S. edit: I have found this article speaking of the same motor
https://www.experimental-engineering.co.uk/2016/03/03/dyson-dc35-digital-teardown/

 

[supak111]

I ended up using an 3-phase ESC from RC cars but got a new vacuum motor that uses 3 coils.
This new motor is waaaay more powerful at 500watts which helps a lot for my specific project

 

[FrankBolleri]

I ended up using an 3-phase ESC from RC cars but got a new vacuum motor that uses 3 coils.
This new motor is waaaay more powerful at 500watts which helps a lot for my specific project

View attachment 60868

Thanks for sharing this info!
Francesco

 

[FrankBolleri]

Finally, I have done it running!
Not yet at full speed... but it run smoothly.

Here the final approach:

Control Dyson DC35 Multifloor vacuum cleaner motor

Eventually, yes. You would have to work up to that frequency from zero, to allow the rotor to accelerate. The Hall sensor, correctly positioned, would trigger a microcontroller to switch polarity. The devil is probably in the control detail. I imagine that, because of the rotary inertia, timing...

forum.allaboutcircuits.com

If you want the full path, look at thread start:

Control Dyson DC35 Multifloor vacuum cleaner motor

Hello all, let me start by saying that I only have a little hobbystic knowledge in the field of electronics and electrical engineering. But I'm becoming passionate about this topic below. Trying to modify my old Dyson DC35 Multifloor to work with a power supply, I burned out the controller...

forum.allaboutcircuits.com