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You know,I'm really interested in putting together a Cct. for just
pulsing this motor . I reckon if someone out there could post a simple
Cct. ,I 'll put it together and try it out.
I'm so frustrated watching the blades quiver in a moderate wind ,but just being held back by the large diameter cogging .
Anybody want to take up the challenge ?
I'd prefer that the pulse(or whatever) is given from down at the
control box -I have the 3 phase ac leads coming down ,not at the top.
Bruce Bushboy
RossW Guru
Joined: 25/02/2006 Location: AustraliaPosts: 495
Posted: 10:34am 11 Mar 2006
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Bruce, please excuse the horrid sketch... if you have access to a
two-pole momentary-contact pushbutton (or a spring-return toggle
switch, or if you wanted to get really creative - a spring-return,
centre-off switch - you could "step" it by hitting phase 'a' then
'b').. this baby is a simplified diagram of what I think should work.
Beware, there's no current limiting, so just a quick pulse only!
As you can see... closing BOTH poles of the switch at once, will in
effect, put your entire battery across one of the coils. You shouldn't
blow up any diodes, because the other diode in each 'vertical' string
is still reverse-biased.
If you want another (horrible) sketch showing connection of the changeover/centre-off switch, just holler.
RossW
brucedownunder2 Guru
Joined: 14/09/2005 Location: AustraliaPosts: 1548
Posted: 02:35pm 11 Mar 2006
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Thanks Ross, I thought it would be a lot more complicated than that.
I'll put this together on a test stator/rotor on my bench and see what
happens. I've been told if I turn one F&P set-up ,having it
directly connected to another similar ly wired unit beside it ,then
maybe the turned one will turn the other (will try this also),
So frustrating seeing the mill sit there for 3 days now ,even with some
breeze-I'd rather see the bloody thing turning ,evrn if it's not
producing any power !!.
Bruce Bushboy
RossW Guru
Joined: 25/02/2006 Location: AustraliaPosts: 495
Posted: 08:33pm 11 Mar 2006
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I'm a great believer in NOT making things any more complicated than they need to be.
Some feedback would be appreciated. My "gut feeling" is that we really
need two phases pulsed in sequence but someone else said just a kick is
probably all it needs.
Yes, that should work - the only thing I can see causing it not to work
would be if the low speed required to get it started wouldn't be
producing enough (useful) output to drive the one up the mast, but give
it a go.
If you have a "spare" motor to play with, and some old low-resistance
current limiting devices (can you say "old car headlights"?), you could
make a safety device by putting one in series with either of the
switches to limit the current to a safe value.
Absobloodylutely!
brucedownunder2 Guru
Joined: 14/09/2005 Location: AustraliaPosts: 1548
Posted: 10:52pm 11 Mar 2006
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Hey, I had a thought ,now that could be a problem, anyhow
, what about if it needs pulses,then have a current sensing coil around
the phase line (ac) and a 555 timer . Now inject a pulse ,the sensor
picks it up as "on" ,the timer then turns it"off" . then the cycle
repeats if the motor dosen't keep revolving -as if it does it's job
,then the current sensor will not allow the timer to kick in again til
it comes to a stop.
whaddathink.
ps - we found Dad, so today we are going to plant him. my sis died and didn't tell anyone where she hid him.
hahahaha.
havaniceday
bruce Bushboy
brucedownunder2 Guru
Joined: 14/09/2005 Location: AustraliaPosts: 1548
Posted: 01:19am 12 Mar 2006
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Tried that --no luck , it moves the blades a very small distance
-maybe a pole on the stator(like we think should happen) , but thats
about it . and the more u do it the less it becomes-maybe gets
saturated ?.
Tried the "motoring one with another " no movement at all-. So, until I
refine something then the wind will have to do it's job !!
Anyhow , that's about it .
Bruce Bushboy
RossW Guru
Joined: 25/02/2006 Location: AustraliaPosts: 495
Posted: 01:52am 12 Mar 2006
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brucedownunder2 Guru
Joined: 14/09/2005 Location: AustraliaPosts: 1548
Posted: 09:27am 12 Mar 2006
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Thanks Ross- I'll try that tomorrow- just a breeze here at
present , so nothing to get excited about .mill is swinging to point in
the right direction , butquivers a bit ,trying to overcome the cogging
effect-thanks for your help.
bruce Bushboy
RossW Guru
Joined: 25/02/2006 Location: AustraliaPosts: 495
Posted: 10:05am 12 Mar 2006
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Thanks Ross- I'll try that tomorrow- just a breeze here at
present , so nothing to get excited about .mill is swinging to point in
the right direction , butquivers a bit ,trying to overcome the cogging
effect-thanks for your help.
I probably shouldn't tell you about the day here then?!
About 0900 I climbed the mast since it was dead calm. I took some
surplus supermagnets up with me - some 3g ones and some 80g ones.
Managed to get the "light" blade pretty much on track with 9g added at
the tip (these little magnets shouldn't throw off, they're N45 and
stick like the proverbial sh!t to a blanket). Then by gently running
the mill a little at a time, was able to work out where the remaining
heavy point was, and since the opposite side was in between blades, I
couldn't add it out at the end, so used the 80g magnet right in on the
hub. Got the prop almost perfectly (static) balanced. Within 10 minutes
of this, the breeze had sprung up enough to get the mill spinning so I
thought I better get down - but upside, I couldn't feel any vibration
while I was up the mast even.
A couple of hours later and I was watching a good north-westerly
putting 13 amps at 50V into my batteries. (650 watts - that's nearly 50
amps into a 12V system). Anemometer shows it was only 30-35 kmh wind
too. The mast still has a slight shake but nothing like the moster
rattle it had before!
I'm a happy dude right now, and hope it blows all night, because the
guys failed to deliver more propane on friday and I'm nearly out!
RossW
Chris
Senior Member
Joined: 12/09/2005 Location: AustraliaPosts: 146
Posted: 12:50pm 19 Mar 2006
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I dont think its worth taking power from the battery to jump start your wind gens.
You should create a slave windmill setup, something small like the nicd windmill charger setup. Use this to jump start your windmill. This way you dont have to worry about draining your main battery, and you can pulse it more often. The smaller slave windmill will turn easier in lighter winds too. So it should maintain its charge pretty well.
I guess it depends on your setup, how often you pulse the generator. etc