Author Topic: CHANGING GENERATOR MOTORS 2 Fisher and Paykel  (Read 31210 times)

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captainward

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Re: CHANGING GENERATOR MOTORS 2 Fisher and Paykel
« Reply #66 on: March 14, 2014, 09:08:20 PM »
Well here's the completed tower with base hinge and painted.  :O)

captainward

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Re: CHANGING GENERATOR MOTORS 2 Fisher and Paykel
« Reply #67 on: March 17, 2014, 06:30:24 PM »
Hello, here is the latest photos of the tower build, still working on the generator alignment.
:O)


captainward

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Re: CHANGING GENERATOR MOTORS 2 Fisher and Paykel
« Reply #68 on: April 10, 2014, 05:19:41 PM »
Well I said i was not going to make the blades myself but here I am making the blades myself, they were not as hard as I thought it would be to get them close to working order.  more blades to follow.....  :O)

I did the anti coging on the generator and it helped a little.
The red spots are a little wood filler.

shawn valpy

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Re: CHANGING GENERATOR MOTORS 2 Fisher and Paykel
« Reply #69 on: April 20, 2014, 01:12:45 AM »
Hi just to add my two cents  :) I ran a dual f&p hawt mill for ages (only changed to get more power) and I used a hand carved taperd twisted wood prop it worked just fine I did go 3 meter diameter though do not try to electric short for braking it just makes them spin faster, RPM will not hurt your stattors I have very high winds here all you have to think about is huge tilt back for tower clearance and maby Glens manual fold for winds over 150 k, mine servived winds like that often with no manual fold and (very poor furling)
your build looks great keep up the good work
 
Shawn

captainward

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Re: CHANGING GENERATOR MOTORS 2 Fisher and Paykel
« Reply #70 on: April 20, 2014, 01:36:02 PM »
Well Thank you Shawn, The tower will be tipped down in the event of high winds with a winch. it is only 15 ft high.

birdhouse

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Re: CHANGING GENERATOR MOTORS 2 Fisher and Paykel
« Reply #71 on: April 20, 2014, 04:18:15 PM »
Quote
do not try to electric short for braking it just makes them spin faster

i've never heard of this.  maybe the user was opening the circuit and not shorting? 

does anyone else have experience with a mill spinning faster after shorting? 

adam

Flux

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Re: CHANGING GENERATOR MOTORS 2 Fisher and Paykel
« Reply #72 on: April 20, 2014, 04:44:39 PM »
Seems perfectly possible. The F & P was designed as a salient pole motor and when used as an alternator it will have a very high leakage reactance.

When operating the output will be determined by the combination of resistance and reactance. As the speed increases the reactive component will increase and at the point where resistance equals reactance the power generated will start to fall. As the speed increases more the current will tend to become constant.

With the thing still charging the battery you will have a load dependent mainly on the battery volts and the limited current.

If you short it and speed is way above the turnover frequency it will be equivalent to driving a conventional alternator into a large inductance. It will tend towards zero power factor. If there was no internal winding resistance it would take no load to turn it.  There will be load from the power lost in the internal resistance but it will be less than the un shorted case where you are powering the internal resistance and the power into the battery.

You will never see this effect with an air gap machine as you will never get much above the turnover point even with ferrite magnets. A motor conversion will be less reactive than a salient pole machine and only in exceptional cases would you see it speed up, but it will go into current limit and that is one reason why these conversions are difficult to burn out.

Flux

joestue

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Re: CHANGING GENERATOR MOTORS 2 Fisher and Paykel
« Reply #73 on: April 20, 2014, 05:51:03 PM »
Quote
do not try to electric short for braking it just makes them spin faster

i've never heard of this.  maybe the user was opening the circuit and not shorting? 
adam

my 30 pole motor conversion shows this feature quite readily.
At 1750 rpm, shorting the motor causes 9 amps of line current to flow, which is only 240 watts of copper loss, combined with 50 watts iron loss makes about 1/2 hp shaft input (open circuit would be 100vac at 435 hz).
But into a resistive load, the motor would have no problem delivering 3 amps at 100vac per phase, which would be 900 watts of real power.

imagine for a moment the copper windings have zero resistance, and the rotor has no iron loss.
all of a sudden, turning the rotor is effortless.

maximum torque will be at some point where the leakage inductance or airgap inductance's reactance is equal to the load resistance+ copper resistance.
if i'm not mistaken that is.
My wife says I'm not just a different colored rubik's cube, i am a rubik's knot in a cage.

shawn valpy

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Re: CHANGING GENERATOR MOTORS 2 Fisher and Paykel
« Reply #74 on: April 21, 2014, 03:23:57 AM »
Yes guys even if you short it when there is no wind high winds can and do overcome these iron core motors ,as for stoping it in a good wind forget it!!   nothing at all like my new neo mill with no iron core.
Im sure others have already told you this but the best thing to do is get it as high as you can as for tilting down every time you get some decent wind I would get very tired of doing  that. 

captainward

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Re: CHANGING GENERATOR MOTORS 2 Fisher and Paykel
« Reply #75 on: April 22, 2014, 06:31:43 PM »
HERE IS THE WORKING WIND TURBINE.

domi

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Re: CHANGING GENERATOR MOTORS 2 Fisher and Paykel
« Reply #76 on: April 26, 2014, 06:58:46 PM »
Good job you have done but thebackshed.com.au (?) lists a seller of a dual-F&P shaft which, hopefully also ensures there is no cogging as the two ends have slightly different positions, i.e., the "rifling" is offset to avoid cogging. Spline is a better word than "rifling". So the two splines have been milled offset in other words.

Unless you modify the poles as suggested on thebackshed you have major cogging problems.

captainward

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Re: CHANGING GENERATOR MOTORS 2 Fisher and Paykel
« Reply #77 on: April 26, 2014, 09:12:18 PM »
well
Domi  I very carefully filed the metal to a domed shape as the backshead advised this cut the cogging in half then i put extensions on the blades to improve leverage now the turbine turns up a 5 mph and at 8 mph we got 15 volts at 15 mph we got 40 volts!!!  :O)  Thanks for the kudos. alot of work.   

Now my problem is how can I keep the voltage at say 14 volts when it goes to 40 volts dc at higher wind speeeds or gusts so i will not  damage my batterys?  anybody know the electrical answer?  Thanks for L@@king.
« Last Edit: April 26, 2014, 09:19:23 PM by captainward »

ruddycrazy

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Re: CHANGING GENERATOR MOTORS 2 Fisher and Paykel
« Reply #78 on: April 27, 2014, 01:06:12 AM »


Now my problem is how can I keep the voltage at say 14 volts when it goes to 40 volts dc at higher wind speeeds or gusts so i will not  damage my batterys?  anybody know the electrical answer?  Thanks for L@@king.


Another way to help decogging is to twist the poles which works pretty well to stop the cogging. Now a few years ago for a laugh I got some 400 volt 470uf electrolite caps and hooked them up back to back to make them non polizarised. Put them in series on each wild AC leg and was surprised at the increase in current. This was using a 100 series hooked up in delta with a 3 metre prop. With the caps out I was seeing around 6-7 amps @ 250 rpm, with the caps in series for the same wind speed I was seeing 11-12 amps. If you can get some caps give it a go and see if it works for you.

birdhouse

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Re: CHANGING GENERATOR MOTORS 2 Fisher and Paykel
« Reply #79 on: April 27, 2014, 07:39:38 PM »
it's normal for a 12v mill to put out 40v while unlodaded.  when you hook it to a battery, the battery will "clamp" the voltage to the batteries voltage.  this is when amps start flowing into the battery.

you might be shopping for a tristar ts-60 soon and a dumpload as well! 

adam

captainward

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Re: CHANGING GENERATOR MOTORS 2 Fisher and Paykel
« Reply #80 on: April 27, 2014, 08:36:11 PM »
Hi All Thanks for you input.

I am not having a problem with cogging as it starts up before the rpms get up to 12 volts so this is good.
The last three days it has been whrlling around just fine averaging 20 volts with about 12 mph winds.