Wind turbine lost its power

[Shadow]

My one wind turbine seems to have lost its power.I've just been using it about one day a week to charge up battery bank as were building our basement.Otherwise it stays shut down.

        In a 20 mph wind such as today its often almost furled and putting out 15-20 amps.{I've seen as high as 26-28) Today over the course of almost 2 hours most I seen was 4 amps. Battery voltage is 50-51 volts. Normally in an hour it would have that battery bank up to about 57 volts.I checked any 2 AC terminals all are about 40.9 volts.Its not furled and just not producing power, I've become accustomed the sound it makes when it really putting out, and its not making hardly any sound.

        Could rectifiers be bad? What happens when they go? Nothing has changed since last week as far as wiring or configuration.

         This is the "Firepower' one. Dual rotor, 3" by 1" by 1/2" mangets,9 coils of 15.5 wire 110 turns. 14' blades.Cut ins about 125 rpm.Wired in Star for 48 volt. Bridge rectifiers are 30 amp. As I said its been in the shorted out stage most all week and we've had some high winds which kept it turning slowly constantly, could this have damaged the stator?

            Any ideas where to start looking? I may not get back on to respond for a day or so after tonight. Thanks

[DanB]

Have you noticed that it's spinning faster?  Odd that you're measuring output on all the AC leads.  I wonder if its not rectifiers...

Does it shut down properly if you short it?

A good way to test teh stator is to send 12VDC up each phase one at a time and measure the current - it should be the same on all 3 phases.  

[harrie]

Dan, can you do this even tho the props are in high RPM, or do you need to wait for a calm day when the props are not turning and not producing power?

[Shadow]

Dosent seem to be spinning any faster than normal,About half as fast as the other one that I just put the 100 feet of extension cords on, it has wayyy to much resistance). As far as shut down it seems normal, I use a 2000 watt wire element from an electric furnace to shut it down. I connect it then disconnect from the battery bank, as the element heats up the turbine slows to a halt then I close the knife switch .

          How do I make the connections to send 12 volts up? Positive on the ac post, and negative where? Then hook a current meter/shunt in series on one side?

             

[DanB]

I just send 12V DC up any two of the 3 AC leads coming down (do it to all three possible combinations - all three phases).  When you do it should jolt the machine/make it turn a bit and being that its a 48 V machine you shouldnt risk overheating things - at least not very quickly.  The current should be about the same for each combination of 2 leads (each phase).  If its not then I would expect a short in the stator somewhere - if it is, then its probably rectifiers.  Of course - it makes sense to test your rectifiers before you do anything drastic.

[harrie]

Repleying to my own post, guess it must have been a stupid question? I just couldnt figure out how you would stop your Turbine to accomplish what Dan suggested. I know you dont climb, so you couldnt tie your blades down!!. Sorry I asked!!!!!

[DanB]

yes, sorry I didnt reply.  Youd have to wait for a calm day.

Maybe you could short one phase and test two - then short another one and test the other two - I suppose that would work.