I have an 80 sp on 24v with 12*800 a'hr batteries, running the house via an outback invertor. The mill runs 3 ph down the pole to the shed, about 50 meters, is rectified with 3*35 amp recitifiers on a large heat sink. From the rectifier, through an amp meter then direct to bank. The c40/60 is wired seperately direct to the battery.
The system normaly generates 18-19 amps.
Something has gone wrong recently and I just cant find it. The mill is currently rotating @ 170 hz producing 5 amp in a strong wind. Pull any one phase wire off a rectifier and it will quickly accerate up to 400 hz generating 18 amp. Connect the phase back in and the machine will holds its revs for about a minute and then die back. This works for any phase. I've changed rectifiers. I've used a car rectifier. The rectifiers all test ok. All wires are checked back to the mast. The head looks ok. There is no effort to spin the blades. I've crossed/shorted the phases with the mill on the ground and there is definantely alot of resistance which disappears when the test short is removed.
Another thing I could never work out which could be related. When the mill was working properly I was playing around with motor 50 uf 400v capacitors across the phases(all I had). This made the mill die away as well to about 5 amp from 18, which when removed, the mill would reaccelerate.
I live on a remote (windy) Is off New Zealand, own gernerator, big farm, few resources etc.
Several other mechanical problems had developed with my set up, the bearing had spun on the shaft etc. This has all been tidied up, the air gap is right now etc. I'm beginning to suspect the old 2m dia 2 blade wooden prop. It is hard to start, I useually have to give it a spin on the ground to get going. If it does come out of cog on a windy day by itself, it will rotate very slowly in severe stall below generteing range. It will generally sulk for a long time like this, but once a gust gets it into the 150 hz plus range it can accelerate to over 500 hz in furl.
I think the problem is either;
- Some sort of phase short that only occurs when current is flowing
- The rebalanced mill is taking to much grunt and blades cant cope
I would appreciate some advice if anyboy can see something obvious.
Regards
Windyrock.
PS Your board is incredibly usefull when you live in a remote place.