I got wind.
There I was staring glumly out the window at the prop barely turning. Had replaced the 3 x 35A bridges with a 110A 3 phase unit from RS Components; had replaced the Beewind 50A charge controller sensing across one of the 12V batteries with OptixElectrics' 70A one sensing from the same single 12v batt; and there the turbine was, fixed pointing due West but in the wind shadow of my and my neighbours' houses and doing sweet FA.
Wind shifts a few points, turbine comes out of wind shadow, and Bam! away it goes, and then some. This was the first opportunity to see my new CMS Magnetics 10ft 6 inch fibreglass prop in action, and boy, did that sucker move. Hardly any vibration too, fnar fnar.
Genny hits 24V at 220 RPM, didn't stop there, shot on up to 30V - in a 24V configuration too - and amps piled on and on to around 20A. Prop began to make a lot of noise at around 250 to 300RPM - combination of WhumWhumWhum and whistling like telegraph wires in a hurricane. Presumably it was self-stalling at that point.
New controller went Bzzzzzz...Phut, locked on and didn't let go when wind dropped and genny showing 15V.
Tapped box, nothing. Hit box, nothing. With extreme disgust, got ladder, propped against tower, climbed up and used hand on rotating genny body to slow down and stop the prop, strapped prop to tower, then went back down, took out new charge controller and replaced with the Beewind unit. Have shifted back to 12V from 24V, lower cutin, earlier stall - I hope. Will need to double the number of electric radiators I'm using for the dump of course to compensate for halving the volts.
Controller relay still showing continuity even though sitting on bench: looks like relay contacts welded. Ho Hum.
Note to self: Even though it is a proof of concept temporary design, need an emergency brake on the bloody thing.
2 comments:
Sounds like a promising start. Good luck! Do you have a link/info on the 'electric radiator' dumping method. (New to me).
hi Matthew
Very simple - i looked at "proper" commercial dump loads and at DIY "Wind Your Own Element" types, and then thought "Why bother? All they are are big resistive elements, and normal electric radiators already do that." Out I go to a shop and buy a couple of cheap 240V 3KW electric radiators - it's ridiculous but it's cheaper to do that than to buy the nichrome wire and housings to make one myself. At some point I'll rewire the elements to run at low voltage rather than 240, meanwhile they're connected "as is".
Have also bunged 8 downlighter fittings into a plywood sheet, running them off my 1KW inverter with 50W bulbs in them will dispose of another 400W, and I ought to be able to leave the inverter connected and switch it through the divert controller because with that headroom (less than half-load) there oughtn't to be too much of an instantaneous current requirement "thump" when it suddenly gets power and wakes up.
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