Electric Motor Secrets

[Jetijs]

Ok, how about this?


The startor pole arc is 70 degree of an arc, so is the rotor. Also there is a little bit wider area at the shaft hole.
Thanks,
Jetijs

[elias]

Ok, how about this?


The startor pole arc is 70 degree of an arc, so is the rotor. Also there is a little bit wider area at the shaft hole.
Thanks,
Jetijs

Jetijs,

I think that this rotor will fly to about more than 6000-7000 RPM. This one I suppose will have about 50% more mechanical output compared to the geometry of you previous motor in my opinion, not considering your small airgap, which will increase the torque way up. Wider stators may increase the effect of attraction. I think that this is a very powerful design. I am getting really excited about your new design.

Let's see what Peter has to say.


Elias

[Jetijs]

Thanks for your opinion, elias

[Peter Lindemann]

Looks Good to Me

Ok, how about this?


The startor pole arc is 70 degree of an arc, so is the rotor. Also there is a little bit wider area at the shaft hole.
Thanks,
Jetijs

Jetijs,

This looks like a viable physical geometry to me. The system should be capable of high torque and high speed. In fact, your motor re-wind shop may have a stator very similar to this IN STOCK. If so, we should look very closely at what they have available, as it may save you the step of building the stator from scratch.

Does anybody else have something to add?

Peter

PS.. Jetijs, you may have noticed over the course of the many posts here, that I use the word "stator" and you use the word "startor". The correct English word is "stator". The word is derived from the word STATIONARY, meaning the part of the motor that does not move. The word "startor" is slowly creeping into usage in place of the proper spelling of the word "starter". A Google Search on these two terms shows that the word "startor" shows up 13,000 times, whereas the word "starter" produces 147,000,000 hits. Either way, the word refers to something that initiates a movement, usually the operation of a large engine.

[Jetijs]

Ok, thank you Peter
I guess this is why my grammar spelling program always underlines the word startor I will use the correct word (stator) for now on

[elias]

A question popped into my mind.

Peter,

Wouldn't it be better if Jetijs, used a "+" shaped rotor? I mean wouldn't it add to the mechanical output?

It seems that while one pair of the stators are attracting the rotor, the other pair are just watching.

Elias

[Peter Lindemann]

Poles Waiting...

Peter,

Wouldn't it be better if Jetijs, used a "+" shaped rotor? I mean wouldn't it add to the mechanical output?

It seems that while one pair of the stators are attracting the rotor, the other pair are just watching.

Elias

Elias,

You are correct. The other poles are just waiting. If you put an "X" rotor in this stator, the rotor won't know which direction to turn, being attracted back as well as forward. In fact, it wouldn't turn at all. Think it through. You'll see it.

Peter

[elias]

Yes

Elias,

You are correct. The other poles are just waiting. If you put an "X" rotor in this stator, the rotor won't know which direction to turn, being attracted back as well as forward. In fact, it wouldn't turn at all. Think it through. You'll see it.

Peter

Yes That'll happen, I was not considering the fact that the stators turn on and off separately, I was not sure about how the magnetic flux behaves on the core.

Thanks

[Schpankme]

3 pole rotor/5 pole stator (3x5)

Schpankme,

... The 4 pole rotor mating with the 6 pole stator ... For high torque with no recovery, this design works extremely well.
... for our purposes ... it does not provide space for a "pause" between ... coils going off before the next set of poles are in alignment ...

Peter

Peter, et al

From your critique, it's understood that the Stator density could disrupt the ability to harvest max energy. My goal is a motor that provides max torque and harvesting.

As an alternative here's the 3x5 (3 pole rotor/5 pole stator). My reason for suggesting this geometry is that it lends itself well to keeping mass center of the rotor; compared with the 2 pole rotor, which 'in my opinion' present issues of harmonics/tunning at sonic and subsonic speeds.

- Schpankme

[Peter Lindemann]

How Does This Work?

Peter, et al

From your critique, it's understood that the Stator density could disrupt the ability to harvest max energy. My goal is a motor that provides max torque and harvesting.

As an alternative here's the 3x5 (3 pole rotor/5 pole stator). My reason for suggesting this geometry is that it lends itself well to keeping mass center of the rotor; compared with the 2 pole rotor, which 'in my opinion' present issues of harmonics/tunning at sonic and subsonic speeds.

- Schpankme

Schpankme,

You can see and hear on my YouTube clips that the 2 pole rotor under test is pretty quiet, so I don't see a problem with the issues you raise. Also, I don't understand how you can produce specific attraction cycles with the 3x5 arrangement you are currently suggesting.

Peter

[nali2001]

Core

Hi there Schpankme,
Well a two pole rotor is as much in balance as any other design that can be mirrored. Your design is in my opinion problematic to a fair extend. I presume that you will be firing the coils in '3 cycles' well what this does is that the magnetic attraction is not equal that means that the is a somewhat unbalanced attraction on the rotor. Since you (I presume) only energize one coil at a time this will cause vibrations an stresses on the bearing that must not be underestimated. And it is true that a big problem of reluctance motors is the noise. Since there is a deformation of the core it self happening. And it is a know and little resolved problem with these motors.

Plus the back spike recovery besides circuitry also depends on the material. Very fast materials with high permeability are eventually preferable like Hyperco50, Metglas or even Somaloy but that is out of the question now (likely always)

Kind regards,
Steven

[nali2001]

Simulation

Did a quick simulation
http://home.planet.nl/~sintt000/Simulation.gif
on that core design and to me it seems just fine.

One thing though since the poles of the stator are somewhat close to each other in this design, extra precautions must be take to insure that the rotor looses as much residual magnetism as possible, before it has reached the next stator finger. If not and the next finger coil is loaded it will cause cemf (back emf) and will draw additional currents under load. Just as any other motor. (which will probably be the biggest problem in my motor due to the solid steel rotor)

Regards,
Steven

[lighty]

@nali2001

I know it's a bit OT but I presume you made that simulation in FEMM. Could you please share the simulation file? I'm interested in how did you define the current sources.

[Schpankme]

Phase Switching & Rotation

Schpankme,

... the 2 pole rotor under test is pretty quiet
... how you can produce specific attraction cycles with the 3x5 arrangement

Peter

Peter,

Your point is well taken; my thoughts were to create Phase Switching & Rotation of the Rotor to achieve max drive torque.

Regarding Rotor assembly - the rotor made from multiple plates and held with multiple nuts & bolts, looks to be a low tech way of achieving max performance?

- Schpankme

[nali2001]

Simulation

Well I did not use a 'coil material' so there are no current sources. I just used magnets in the simulation - to simulate the coils.
http://home.planet.nl/~sintt000/Motor.FEM