HK 4540 prototype winding

[powercroco]

gerling has not shown a significant advantage against the normal wind.

remember the "over all" losses diagramm.
If the part of the iron generated losses at the point of work is lower than 2% of all losses, you could bring them down to 50% and in real life you will find nothing, because of the resulting difference is lower than the precision of the normal meassurement instrument.

for our use (high power load) are the addition ohmical losses generated by the longer wires into the needed jumps to stay within the gerling rules a negative influence.
the second problem is the lower copperfill into every second slot (14 wires against 16 wires) and the third problem is, that you are fixed into the 8+7 turns, what recuses the options the get the targeted n spec.

you should try to wind and meassure it!
all you need to do this, is to read the drawing into the gerling paper.

I use a linaer row of the 12 teeth, fill in the just known and try to connect the given parts into the right way regarding the basic rules.

okay, in this special case I needed a complete evening and a special hint of one of my friends, but then the winding diagramm was ready very fast.

[1BOHO]

In the Gerling papers the basic 12 tooth scheme was not clear to me other than suggestive skipped teeth thus those odd schemes I came up with Kw above .90.I never wound. I saw nothing on 12N showing FSCW with the skipped teeth and over lap simultaneously. I was not convinced by the diagrams showing coils 180 degrees out or Pi, that what I would attempt on the 12N would be what was intended and did not want huge box of used copper. The Gerling scheme in the diagram on rc groups doesn't seem at all special other than the one coil in a single phase turned last.I can certainly wind it was also unsure if it was the intended scheme. In the end I was more comfortable with and in reading Gerling I was more interested in the 18N and 24N configurations, With the skipped teeth and the overlaps but dont have that stator. The 7/8 is not limited to 7 plus 8 turns as I understood but representative of that percentage 87% or ratio. Certainly there are other integers that would work or be very close if that interpretation was correct. Also what happens with the "last turn not being wound" I did not comprehend from any of the diagrams unless it tried to relay end turn transitions on each end of the stator.

[powercroco]

if you combine the turns in right manner, you will have all ends on the same side, as all beginnings!
thatswhy I said, you should draw them all linear and connect them in right way.

may be, a photo the front side will bring you and all the readers in the background (just like the criminal peter) to the right idea.
you can see the long unused jump wires:



every tooth has 7 arcs and into every second slot are laying the 2 needed additional wires to fullfill the "8/7 gerling rule".
btw. the very stupid winding suggestion in rclineforum was a source of fun for us for some days and I personally have stored it into my private collection of "most stupid winding ideas ever" at a place of honour.


and yes, to write "8/7" ratio would have been better.
in fact someone will have 16 and 14 wires into the slots in 16-16-14-14-16-16-14-14-16-16-14-14 -row.
the shown stator is 8+7 YY = the same n spec as 4+3,5Y
I is not easy to say clear enough what you mean, if the used language is not your native one!

for a good windable 18N or 24N statorshape you will need some more diameter than 40 to 50 mm.

[ron_van_sommeren]

Originally Posted by 1BOHO

... The Gerling scheme in the diagram on rc groups ...

Do you have a link to that RCG thread/post?

Prettig weekend Ron

[1BOHO]

Originally Posted by ron_van_sommeren

Do you have a link to that RCG thread/post?

Prettig weekend Ron

abBCcaABbcCA
You will see the oddly wound phase to tooth 11 if you put it in the winding scheme cal.

[1BOHO]

Have you had the time to analyze the BEMF of the motor? That you can see without discrete measuring equipment to measure efficiency.Nevertheless I don't see why such would need to be so discrete if you actually measure real torque and rpm with a torque cradle not mathematical models.

[powercroco]

no.
I put it back into the box immediatellyafter reading you PM.
After doing some easy meassurements I do not believe, that it could be an significant advantage for my personal use in speed planes.

and to be true: after knowing all the follows this winding causes, I have no fun in working with it anymore.
never thought, that some motorbuilders could be so crazy and so criminal!!!
I think I will remove this winding soon and use the parts for a "practical" motor.

[1BOHO]

More significant harmonic reductions will require the 18 or 24 stator and some other things....
Still seems you could apply Gerling flux barriers, magnet segments, etc. to the cofe stator and rotor and see some improvement.

Did you measure the operating temps vs DLRK at a load?

[powercroco]

nothing more about "gerling-type" of motorwind from my side.

magnet segmentation brought nothing significant.
what works in big machines, must not cause significant changes in our much smaller motors.
btw. this was the result we ever found, if someone of us tried to realize such suggestions.
may be the reason behind:
after doing the segmentation the magnets in big machines still are bigger than the whole magnets in ours.....
I also never found data about a meassured win from the "first protagonist of crazy ideas" into modelinbg sized motors. only theoretics, like much others.

back to real world!

[1BOHO]

Ok take care.