The Axial motor ”Doppelrumba engine”

[Monie]

I´m trying to make an axial-motor also known as a ”Doppelrumba”
as pictured beneath.
www.sunwind.dk/projekt/axial-motor.jpg

Here is the axial outrunner engine I´m trying to develop
The winding method for the spool/stator 9N12
www.sunwind.dk/projekt/spoler.jpg

Kombinationstabelle:ABCABCABC
The 9 spool consists of 80 windings where the thread thickness is 0.6mm.

I have tried to test the engine by connecting a 9V battery in these following different ways:
+A, -B
+C, -B
+C, -A
-A, +B
+B, -C
-C, +A

Results:
All the steps followed the rotor (ourrunner), 370 degrees anticlockwise without any problems.
The ends are connected as 3-phase (Delta), but when the engine is connected to a speedregulator of type FLY20A. When that is happening, the rotor turns 3 nudges roughly 30 degrees anticlockwise, after that it just stops.

Please look at this homepage:
http://www.himodel.com/electric/HiModel_AS_Series_3-10S_Brushless_Motor_Speed_Controller_HV-45A.html

- What can be the reason for it to not want to keep running?
- Are more magnets needed- and are they supposed to be of a greater width?
- Or shold I place the magets in a different way?
- Do you have any ideas to how I can make it run properly?

I hope you will be able to help me with this matter, and I´m looking forward to hearing from you.

Best regards
Monie

[wmcneal]

I'm certainly not an expert on brushless motors by any means, but when I have experienced such symptoms it was because one of my phase windings had an open in it. Check all your windings with an OHM meter. If you get equal readings on all windings then you might just have a timing problem or one of your magnets may be backwards or maybe one of the windings is wound backwards. Just some things to check.

[BeavrdamElectric]

A very interesting project! Do you have any pictures of the motor before assembly? It's a little hard to see what is what.

Your testing should have confirmed continuity, and coil winding and magnet directions (if all the steps were identical). Have you tried spinning it to get it started? Does your ESC have timing settings? The link you gave only says the unit has "timing advance" (no link to instructions), plus it isn't the "FLY20A" you mentioned.

Good Luck!

[Monie]

To BeavrdamElectric

Here´s the 9 spools.
www.sunwind.dk/projekt/axial-spoler.JPG

Here´s the engine without the 16 magnets.
www.sunwind.dk/projekt/Spoler.jpg
The spools are connected to a 3-phase delta.
A to X
C to Y
B to X

The Phases A,B and C are connected to a speedregulator as shown at this website.
Please look at this homepage:
http://www.himodel.com/electric/HiModel_AS_Series_3-10S_Brushless_Motor_Speed_Controller_HV-45A.html

www.sunwind.dk/projekt/speedregulator.JPG
Where the arrow is pointing there´s a light flashing, what does that mean? ( twice a second) Speedregulator model HV-45A
You´re able to see the manual here: http://www.himodel.com/en/info/manual/HIMODEL_AS_ESC_EN.pdf

If you go to this website, you´ll be able to see a video of a testdrive of the engine. It might take a while for it to download though… ;-)
Download here:
www.sunwind.dk/projekt/MotorRunning.MOV

What do you think is wrong? Does it have anything to do with the ESC timing settings, or should the magnets be of a greater width?
www.sunwind.dk/projekt/magnetrotor.JPG
Here´s the 16 magnets when they´re placed changing between north and south.

When I´ve got the engine up and running, you´ll be able to get the material for this type of engine, if you like. I´m looking forward getting your reply.

Best regards
Monie

[ScubaSteve]

monie,

like wmcneal said, check our termination connection and also your motor lead -> esc connections. often they are the culprit behind "studdering" motors.

also doublecheck with a 2nd ESC - your Himodel esc might be having a problem with that motor. very cool project though - i'd like to see some build photos as well. :)

[BeavrdamElectric]

To BeavrdamElectric

Here´s the 9 spools.
www.sunwind.dk/projekt/axial-spoler.JPG

Here´s the engine without the 16 magnets.
www.sunwind.dk/projekt/Spoler.jpg
The spools are connected to a 3-phase delta.
A to X
C to Y
B to X

The Phases A,B and C are connected to a speedregulator as shown at this website.
Please look at this homepage:
http://www.himodel.com/electric/HiModel_AS_Series_3-10S_Brushless_Motor_Speed_Controller_HV-45A.html

www.sunwind.dk/projekt/speedregulator.JPG
Where the arrow is pointing there´s a light flashing, what does that mean? ( twice a second) Speedregulator model HV-45A
You´re able to see the manual here: http://www.himodel.com/en/info/manual/HIMODEL_AS_ESC_EN.pdf

If you go to this website, you´ll be able to see a video of a testdrive of the engine. It might take a while for it to download though… ;-)
Download here:
www.sunwind.dk/projekt/MotorRunning.MOV

What do you think is wrong? Does it have anything to do with the ESC timing settings, or should the magnets be of a greater width?
www.sunwind.dk/projekt/magnetrotor.JPG
Here´s the 16 magnets when they´re placed changing between north and south.

When I´ve got the engine up and running, you´ll be able to get the material for this type of engine, if you like. I´m looking forward getting your reply.

Best regards
Monie
OK, I looked at everything but the video - it would take over 1 Hr to download - Ma Bell believes in tin cans and string around here. Maybe tonight.

I thought 16 magnets might be the problem, but the pix show 12. ;)

I can only assume the flashing light is to let you know the ESC is operative and whether the brake is on or off (single VS double flash). How are you controlling the ESC, with a transmitter and reciever or a servo tester?

Like the others mentioned, double check all your connections.

Is there any iron behind (in front of?) the magnets? That wouldn't keep it from running but some "back iron" would make it more efficient. If you could put another rotor on the other side of the coils it would be nice. That's what I thought of when I saw the thread title. I have seen web pages about wind generators built that way.

Good Luck!

[olmod]

If its not a connection related problem maybe its to do with the back electro motive force requirements of the ESC,i would imagine that the designers of the ESC have set parameters and if the BEMF does not fit those rules then it may not work, if you have the test gear (CRO) you could measure a standard motor across a phase then measure yours and compare while driven with a bench drill , i really dont know im just throwing suggestions out there :)

[Monie]

To BeavrdamElectric an all

As you wrote: >I thought 16 magnets might be the problem, but the pix show 12. <
That was a mistake. The engine is 9 not and 12 magnets.

New show for running motoren:
www.sunwind.dk/projekt/MotorRunning.wmv

Best regards
Monie

[BeavrdamElectric]

To BeavrdamElectric an all

As you wrote: >I thought 16 magnets might be the problem, but the pix show 12. <
That was a mistake. The engine is 9 not and 12 magnets.

New show for running motoren:
www.sunwind.dk/projekt/MotorRunning.wmv

Best regards
Monie
Thanks for redoing the video! Is that as far as it goes or did you stop it at that point?

It could be the ESC, have you tried different timing settings? According to Table A on page 6 of the PDF, the default setting is for 6 and 8 pole motors. I think there have been cases of the wrong setting causing such problems.

Your work looks meticulous, I doubt you have any coils wound or mounted the wrong way or magnets mismarked, and the connections look secure.

Good Luck!

[Monie]

As you wrote: >I thought 16 magnets might be the problem, but the pix show 12. <
That was a mistake. The engine is 9 not and 12 magnets
An additional question:
According to the Combinationstabelle for 9Not 16Pole
Look at this homepage:
http://www.powercroco.de/Kombinationstabelle.html

Are the windings for the 9 spools: AbbCaaBcc

But looking at it from a practical point of view, how are the windings supposed to be made, from the drawing below?
Show her:www.sunwind.dk/projekt/9Not16Pole.jpg
Here´s the windings for 9Not og 12Pole winded like this: ABCABCABC
That means it´s winded the same way around on each not and that:

Not 1-4-7 = C
Not 2-5-8 = B
Not 3-6-9 = A

But for 9Not and 16 pole, how is the windings supposed to be done with AbbCaaBcc?
Would you be able to help out with the above, and write the numbers for the spools: AbbCaaBcc?

Best regards
Monie

[BeavrdamElectric]

As you wrote: >I thought 16 magnets might be the problem, but the pix show 12. <
That was a mistake. The engine is 9 not and 12 magnets
An additional question:
According to the Combinationstabelle for 9Not 16Pole
Look at this homepage:
http://www.powercroco.de/Kombinationstabelle.html

Are the windings for the 9 spools: AbbCaaBcc

But looking at it from a practical point of view, how are the windings supposed to be made, from the drawing below?
Show her:www.sunwind.dk/projekt/9Not16Pole.jpg
Here´s the windings for 9Not og 12Pole winded like this: ABCABCABC
That means it´s winded the same way around on each not and that:

Not 1-4-7 = C
Not 2-5-8 = B
Not 3-6-9 = A

But for 9Not and 16 pole, how is the windings supposed to be done with AbbCaaBcc?
Would you be able to help out with the above, and write the numbers for the spools: AbbCaaBcc?

Best regards
Monie
I realized that you stated 16 magnets by mistake. :) I don't think going to 16 magnets will help, it's listed as a bad combination in the table. I tried a 14 mag, 9 tooth motor, it was very inefficient. Have you tried a wye termination?.

The winding you list, AbbCaaBcc, is actually in the chart for 20 poles. No matter, it's the same as the 16 pole winding with all the coils reversed in winding direction (and starting in a different place). What it means is;

Short version: The numbers follow the sequence. 1=A, 2=b, 3=b, 4=C, etc.

Long version: Wind the first tooth, and call it "A". Start the second tooth with another wire, winding the opposite direction, and continue to the third tooth, winding it identically to the second. Start the fourth tooth with a third wire, winding the same direction as the first. Then with the first wire, wind the fifth and sixth teeth like the second and third. Now take the wire fron the second and third teeth, and wind the seventh like the first. Take the third wire and wind the remaining two teeth like the second and third.

It makes no difference which way you start as long as you keep the capitol letters wound in one direction, the lower case wound the other way. You could change the connections on your present windings to rearrange and reverse the coils as needed.

Have you experimented with the ESC timing? Did it make any difference?

Good Luck!

[Monie]

Regarding development of the Axial BLDC motor by Monie.

I´ve been dooing some serious lab. Testing and therefore not beeing able to report progress before now.
Status as of today is: The work on the BEMF timing is giving a me a hard time, but I hope to find a person which is able to help me on this matter, do any of you guys know any one who´s in to any BEMF timing codes, in order to get the motor running? And could be interested in a joint delevlopment set up?
Then please don´t hessitate to contact me.

Best regards
Monie

[BeavrdamElectric]

Have you checked the "DIY Electronics" section of this forum? There are guys there who can design ESCs and would know a lot more than us "mechanics". :)
http://www.rcgroups.com/diy-electronics-199/

I hope you get it going soon! Did changing the ESC timing have any effect?

Good Luck!

[Monie]

Dear Beavrdam

Thanks for your reply.
Unfortunately changeing the timing didnt move anything at all, allthough I keep on struggleing to succeed with my project!

Best Regards

Monie

[Ron van Sommeren]

DIY BLDC discussion
http://www.rcgroups.com/forums/showthread.php?t=200567

DIY BLDC designs
http://www.rcgroups.com/forums/showthread.php?t=140454