However it doesn't tell me whether the coils are series or parallel and given there are 12 AC wires it can't be a single phase rectifier on each coil, so there must be some sort of series or parallel of pairs of coils among the 12 coils present. hmm.
My wife and I have been gone on vacation so please excuse the tardy reply.
This latest generator I built is a dual stator unit with three magnet rotors, the center rotor having magnets on both sides of the disc. It is built for 12 volt battery charging and uses Individually Rectified Phases, hence the 12 wires down the tower. There is absolutely no connection between the two stators. Each of the two stators has nine coils and the start and end of each phase in each one is hooked to a full-wave 50 amp bridge rectifier. The DC sides of all six rectifiers are hooked in parallel.
It develops ~180 DC amps @ 14.5 VDC @ 300 rpm and requires a shaft input of 4,420 watts to get that 180 amps @ 300 rpm making it roughly 59% power efficient at full load after the rectifiers. Each wire down the tower carries about 19 amps RMS and I deliberately used the large wire to get the high efficiency at rated power. It is designed for 16 foot PowerMax blades - the blades came in the delivery truck while I was gone on vacation. I don't have it flying yet - only the generator has been built and tested and now that I'm back home, once I get caught up on some other things, I plan to build the rest of the turbine this week.
To answer Max's question, the individual phase resistance is .13 ohm. It is wound with 63 turns for 98 rpm cut-in driven by the 16 foot rotor, which is 7 mph wind speed, 8 TSR. It is designed to reach maximum power at 28 mph wind speed, 6 TSR, which is just shy of 300 rpm. It started out as a proof-of-concept 2.6 kW 12 volt turbine because I was told by a couple people that it can't be done, or more properly, that a 12 volt turbine of that capacity cannot be built to run efficiently. So instead of building one big huge stator I used a stacked generator layout, with lots of big wires (I'm using two 10/6 generator cables down the tower), IRP with 6 rectifiers, and 2/0 copper from the DC bus at the tower base to the batteries.
When completed it will power my house (in conjunction with a 1 kW solar array) and will replace both the 13 foot machine on the 47 foot tower directly in back of my house and the 10 foot turbine that is presently on a 54 foot tower just north of my house. This turbine is going on the 47 foot tower because the wire run from the tower base to the 3,000 amp-hour battery bank is only 17 feet.
Hope that answers your questions. And yeah, I know it's ridiculous to go to that extent to build a 2.6 kW 12 volt turbine. So you can skip telling me all about how a higher voltage unit would be so much more efficient at the same cost. But my house is 12 volt so I decided to do it anyway. Hell, my solar array made up of ten 123 watt Sharp panels puts out 70 amps and I've seen it put out 80 with the sun shining directly on them. I expect that the solar array will beat the pants off a 180 amp turbine day in and day out in total kWh output. But the solar panels aren't as much fun
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Chris
