Winding terminology etc

[zlatkodo]

General definitions for "conventional" and "consequent" winding are known, but there are differences in interpretation.
What exactly means the terms "conventional" and "consequent" winding?
Can both be single-layer and double-layer? Can both be lap and concentric?
And the most important question: how to calculate the distribution factor for the "conventional" and "consequent" winding? What is the difference in the calculation?
Please, see: here
Zlatkodo

 

[KllrWolf]

Consequent poles could be double layer in a slot, but I do not see a reason. They use the fact the magnetic pole of the wire is the opposite when traveling in the opposite direction (eg. Up-North, Down-South). Of course all my experience is on wet wound motors, and we do not use consequent pole (only seen one manufacture of the type try, and that did not last long).

 

[petronila]

Hello Zlatkodo

I think the term conventional is something created by the book writter. The term conventional is not ofen ussed, the technical terminology suggest use the terms Standard or pole winding and consequent pole winding.
"POLES The magnetic poles set up inside an electric machine by the placement and connection of the windings"
This two kinds of windings have the main difference in the group phase Qty and how are the groups connected,in the standard or pole winding the groups are twice than consequent pole and you connect the end of the first group with the end of the second but in Consequent poles you connect the end of the first group with the start of the second, for it when you draw a 12 groups 4 poles pole winding you can see 4 poles in each phase,two north and two south, each arrow change of direction. But in a six group four pole consequent pole winding sketch you see two norths and you can´t see the other south poles and the other two souths poles are formed do to the magnetic field needs a retourn way.

Both could be lap or concentric.The standard or pole windings are double lawer and consequent pole are usually single layer but you can have special designs.

Attached you will find a technicall information.

Best Regards

Carlos

 

[zlatkodo]

Hi, Carlos,
Thanks for your answer and interesting attachment.
Your description of consequent windings is generally accepted, but there still exists a dilemma.
Look at this diagram with three different windings for 24 slots and 4-pole (shown is only one phase of the single-layer winding).
1. - What is the distribution factor for each of these cases (A, B and C)?
2. - By definition, windings A and B are consequent, C is the standard winding. But B is concentric winding also. Whether a factor is 1 or 0.866 or 0.966?
3. - The question may be simpler: how to declare windings A, B and C and how to calculate the distribution factor for all three cases?
Zlatkodo

 

[petronila]

Hello Zlatkodo

The table has 4 columns,first one shows the coils per group, second : Standard Windings (Not Concentric and no consequents), Third: consequent pole winding(Standard winding and consequent pole too) and fourth: Concentric windings.

Diagram A is a Lap standard consequent 6 groups, span 1-7 with 2 coils per group so is standard, then the D.F from the table will be 0.866 (Third column-2nd row)

Diagram B is a concentric consequent 6 groups span: 6-8 with two coils per group, DF from table will be 1.0 (Concentric windings: The D.F is always equal to 1.0)

Diagram C is a lap standard ( pole) winding, 12 groups, span 1-6, 1 coil per group, DF from table will be 1.0 (Second column, first row)

Summary for design matters: 1. Determine coils per groups of the winding 2. Determine if the winding is lap or concentric
3.Determine is standard or concentric. 4. Go to the table and find the D.F

Regards

Carlos

Carlos

 

[zlatkodo]

I am just now testing a new, someone else program for motor-redesign and here you can see the values of the distribution factors for the aforementioned cases A, B and C, obtained from this program.
What is the formula for calculating the distribution factor for the consequent windings?
Zlatkodo

 

[petronila]

Hello Zlatkodo

This file can help you

Regards

Carlos