rewinding series lap wound dc motor armature question

[tom0001]

The idea is to mod a 4-5 kw starter for increased voltage (lower rpm/v) and decreased current with a longer duty.

Field windings are easy on a starter as they are meant to be replaced (adding 1/3 to the field windings?), the problem is limitation on voltage in the armature, what about having say 3 turns of slightly thinner wire where there was only 1 thick loop on each segment but keeping the pattern, just with a 3 wire coil instead of a single wind?
I'd just like to know if I have the theory correct or will this kill the armature's field.

Thanks Tom.

 

[starkopete]

Without getting into all the caveats the basic formula will be a simple ratio. If you are going to triple the voltage then triple the turns and use 1/3 the wire size (circular mils).

Thanks

 

[starkopete]

A couple of the caeats: volts per bar and brush current density.

 

[tom0001]

Thanks, wanted to make sure, thing is starers are in a world of there own abit, not sure now blanced the windings are to start, should the number of winds on each pole (4 pole) match the number of total winds added for 1-4 of the armature or close to?

just that I know that the 4 field are in searies with the motor circut and the 4 parths of the armature are parallel with each other, so each field hase to be able to take the total armature current.
I know it is vague, but what ever gauge I use on the armature the field windings have to be 4 times the current rating and 1/4 of the total turns of the armature.

have i got it all wrong? any help is very appreciated.
Tom.

 

[starkopete]

Tom,
There are a lot of factors involved with what you are proposing. Disregarding a lot of the things that are involved with what you are trying to do (you have given no specifics)the basic "winding" question you are asking is still a basic proportion. From a strictly winding perspective, if you want to triple the voltage - triple the number of turns and cut your wire size by 3 in all of the windings that you have, armature, fields, interpoles and/or series windings. I am oversimplifying this and I think you may be on a fools mission if you think it is this simple. If you want some advice from some of the people that are smarter than myself on this site (and most of them are) you should be more specific about what you are trying to do.

Thanks

 

[tom0001]

A fools mission, how dare you, lol joking aside of course you are correct I'll source a couple of the motors I'm going to use dismantle, take pictures, measurements and find as much information as I can, motor manufactures don't normally release that much detailed information though.
I was just hoping some one had experience of rewinding dc series motors and may be changing there characteristics.

Thanks again.