Brushless motor winding class

[ray schrauwen]

Just saw this. Basics but informative.

[donhuff]

Yes basic but still he's hitting on the one main thing that WE are interested in, HORSEPOWER and how to increase it. Only he calls it by the electrical proper term ( I think) Torque Efficiency.

He names some ways to increase HP toward the end. Bigger displacement (mainly the size of rotor), bigger/stronger magnets, tighter air gap, and more copper.

[donhuff]

4-Pole-brushless-DC-motor-animation.jpg


Lets have a little test, to see if ya'll have been understand what I've been preaching about.

In the picture above, I want you to describe the motor to me. It's laid out differently that the way I have been drawing them, but it's still showing you the same thing, only in a more congested but all together and round layout. More like a real motor would look if you were to slice it in half across the shaft.


I want to know. Click on the pic to make it big enough to see well.

1 number of turns
2 number of poles
3 number of slots/teeth
4 and the hard one, wye or delta. This might be a little hard for you because of the way it's drawn, but remember it all about where the ends of the wire END.

[donhuff]

And after all my searching and explaining NOW I find this somehow. The picture is a real good drawing of what we've been talking about.

I'll give a link to the forum where I go it to so you can see how this guy rewound his motor. Very ambitious to do it with a single strand of big wire too. I think he needs to learn about the powder coating of the stator.

18n6p diagram.jpg


http://www.rc-network.de/forum/showt...P-Innenlaeufer you'll have to convert it to english.

[T.S.Davis]

1 number of turns 5
2 number of poles 4
3 number of slots/teeth 6
4 and the hard one, wye or delta. wye

Would be easier to see in our usual elevation view we've been doing.

[T.S.Davis]

Don, on the 4 turn DDD example do we end up with three dead teeth again?

Also... that particular arrangement will produce a Kv of X. What ever it is I don't really know. Lets say I use the tach and it comes out at 1500kv or so but I really wanted 1600 for example. Could I just take one turn out of the center coil so that it's 4,3,4? Just trying to make sure I'm getting it.

[donhuff]

1 number of turns 5
2 number of poles 4
3 number of slots/teeth 6
4 and the hard one, wye or delta. wye

Would be easier to see in our usual elevation view we've been doing.

Your right on everything except the number of turns. I see only 2 turns. This is a concentrated wind, so it looks a bit different from the distributed version that we have been doing. But the wire makes only 2 full trips around each tooth.

[TRUCKPULL]

1 number of turns -2
2 number of poles - 4
3 number of slots/teeth - 6
4 and the hard one, wye or delta. - wye

Don - you posted while I was typing.

Larry

[donhuff]

Don, on the 4 turn DDD example do we end up with three dead teeth again?

Also... that particular arrangement will produce a Kv of X. What ever it is I don't really know. Lets say I use the tach and it comes out at 1500kv or so but I really wanted 1600 for example. Could I just take one turn out of the center coil so that it's 4,3,4? Just trying to make sure I'm getting it.

The bottom of the DDD wind, should look exactly like the bottom of a D wind. The difference will all be on the other end where the connections are made.

I don't KNOW the answer to that next question Terry. I know some 4 pole motors have fewer turns on one coil than are on the other coil, on the same phase, and it has a different kv that if both coils had the same amount of turns.
I have never see that on a 6 pole motor, but I don't see why it wouldn't work on them.


BUT, I don't see WHY you would want to leave copper out just to hit a certain kv, when you know more copper means more POWER!!!

Is hitting a certain kv number more important to you than going faster?

It seem like a lot of people relate kv to power some sort of way, that aint true. Kv has nothing to do with power.

[donhuff]

Sure Larry


Just kidding, I believe you. Hard to believe someone types slower than me though.

[TRUCKPULL]

Sure Larry


Just kidding, I believe you. Hard to believe someone types slower than me though.

I had copy and pasted your question,
Then spent the time looking at your picture for the answers.
1 number of turns
2 number of poles
3 number of slots/teeth
4 and the hard one, wye or delta.

Larry

[ray schrauwen]

1 number of turns 5
2 number of poles 4
3 number of slots/teeth 6
4 and the hard one, wye or delta. wye

Would be easier to see in our usual elevation view we've been doing.

Only because I’ve been sleeping in the class I get the same for 2, 3 and 4. I get 1.5 turns for 1.

[ray schrauwen]

I was close! I can understand winding the motor easier with the round cross sectional drawing.

[ray schrauwen]

The bottom of the DDD wind, should look exactly like the bottom of a D wind. The difference will all be on the other end where the connections are made.

I don't KNOW the answer to that next question Terry. I know some 4 pole motors have fewer turns on one coil than are on the other coil, on the same phase, and it has a different kv that if both coils had the same amount of turns.
I have never see that on a 6 pole motor, but I don't see why it wouldn't work on them.


BUT, I don't see WHY you would want to leave copper out just to hit a certain kv, when you know more copper means more POWER!!!

Is hitting a certain kv number more important to you than going faster?

It seem like a lot of people relate kv to power some sort of way, that aint true. Kv has nothing to do with power.

That’s interesting. I forgot you mentioned a bit about this. I look for a certain KV at times that would turn a certain prop on a certain size hull to avoid going too big on prop on smaller hulls that may cause walking.

[donhuff]

Really Ray, 1.5 turns?

Remember in the pics of my practice stators, when I showed the "bottoms" of the windings. It was easy to see the turn count because all 3 or 4 or whatever number was in the turn count, there would be that many strands of wire showing, of the bottom end turns.

DSC_0006.jpg

See here that there are 3 turns. But if you look on the other end it will only show two because of the start coming in , around 3 times, and then the finish going out.

IN the pic in my test, we are looking at it either end I suppose, as the start of a individual coil is on one end, and the finish is on the other. So you should be able to look at either end of this one, and it will show 2 turns. And all the "connections" are on the outside diameter.

I have another pic here that I cant seem to get rid of, that shows the start end. it's not the one were talking about.