Is high resistance good or bad in an alternator?

[DongBeetle]

Hi all, new to this forum..
I'm in the process of building a small 3 phase alternator, consisting of 6 coils and 8 magnets, the wire I'm using is 0.3mm and each coil is just about 675 turns (1350 turns and 80 meters of wire pr. phase)
The thing is, there's about 20,3 Ohm's thru each phase, and that seems high to me,
so.. is that good or bad in an alternator/generator?
And what about heat, is that likely to be a problem? (I do plan to encapsulate it)
Also, I've tried to figure out how to make a switch hookup to switch between 'star' and 'delta' configuretion, can you tell me if what I've come up with is right and will work!?

Regards.

 

[CDRIVE]

Yes, 20,3 Ohm's is high. On this side of the pond .3mm means little to me as we work with AWG (American Wire Gage). My guess is your wire gage is too high, which translates to wire dia too small.

 

[CocaCola]

That is about 28/29 gauge wire, and it has a resistance of about 0.06490Ω/0.81830Ω per foot (copper) respectively... So yeah it's going to be about 20Ω give or take at 80 meters, nothing you can do about that without swapping out to bigger wire or less windings/length...

 

[DongBeetle]

Ok, cheers guys!
Sounds like it's best if I redo the coils, what if I make them 300 turns and use 2 wires (bifillar I guess) that would bring each phase down to about 5 ohm, do you think that will work?
And what about the switch hookup, does it look right?
my biggest concern is when in star 'mode' and the 'N' and the 'Out -' is connected thru a commen ground (the gray line) that it might cause some problem!?

Regards.

 

[duke37]

The size of your alternator will determine the power output. You have the choice of a lot of turns giving a high voltage and a low current or a few turns giving a low voltage and a lot of current.

I think you should wind a coil and see how many turns/volt you get.