3 phase PMA windings

[Rattlesman]

Hi there,
Although I've been watching this forum for several years and have gained quite a bit of PRACTICAL knowledge from it I have just today actually registered as a member. My question is this; I recently aquired 2 used non-functional wind gens that I have idendified as Sunforce 400 watters. I dis-mantled them and found that the integral reg/rectifiers had been pretty well fried so decided I would just use the PMA's and housings to make 3 phase "lecticity" and send it to external rectifiers. My dilema is that in checking out the PMA's I've found that I have 2 heavy guage coils and 1 much smaller gauge winding(=3). The 2 heavy gauge ones ohm out at .5 ohms and the smaller gauge ohms at 1.5 ohms. Does anyone know WHY this PMA would be built like this, and how it might effect my eventual rectification and power output? Should I just go with the flow and not worry about it or is there something I should be WARY of? 
Rattlesman

[birdhouse]

welcoke aboard rattlesman!

i have no direct experience with those exact machines, but i do have an idea of what's going on.  the thinner/higher turn phase is there to give the turbine an earlier cut-in for a small trickle of power in lower winds, then once the machine starts really moving the other two thicker/less turns phases hit their cut-in to really push the amps.  the largest thing i'd be worried about, would be the thinner windings burning up if the furling/speed control is not dialed in correctly. 

yes, you can run three wires down the tower and rectify at the base with three full wave bridges, then run your single phase to your battery bank.  (assuming these aren't grid tied).  it seems many small commercial turbines don't use large enough rectifiers and/or heat sinks.  so find some big pieces of aluminum to mount your new rectifiers to! 

adam

[Rattlesman]

Thanx Birdhouse! I love it when someone can give a straight forward answer. Your explanation is "Perfectly Logical" as Mr Spock would say. I shall proceed as planned and find out what happens 
Rattlesman

[ghurd]

If there are electronics in it, some attempts were made to regulate the turbine by shorting sections of the PMA.
Shorting sections could control battery voltage or RPM.

However it didn't work out for most of them.  Maybe none of them?
If memory serves, an earlier version of the Air-X had one phase with smaller windings, and they smoked.
G-

[Flux]

My suspicion is that it is a copy of the Air 303/403.

The idea of the different windings was that in low winds the high resistance winding came in first and then in higher wind the low resistance windings with less turns came in and dealt with the high currents.

As Ghurd has pointed out, the failure was that the high resistance winding eventually burnt out in high winds. the idea can be made to work by limiting the current in the low wind winding but that removed all the inherent simplicity of the scheme and it was abandoned for en electronic solution that braked the thing to limit high wind power.

If the windings are ok you can probably get something useful out of it with a separate rectifier but I seem to remember the 403 rectifier was something odd.

Flux

[scoraigwind]

If memory serves, an earlier version of the Air-X had one phase with smaller windings, and they smoked.
G-

Yes and that was one of the noises that made the AIR so well loved.  the drone of single phase running.