Leeson PM DC motor

[vwgtiman]

Hello, this is my first post.  Im from Schuylkill County PA.  I am in the very early stages of experimenting with wind turbines and wanted to know if anyone has used one of these Leeson PM motors for a wind turbine setup?  I am not hom enow but im sure it is the 90 or 18o vdc @ 1750 rpm model.  If I hand turn it it seems impressive on my Fluke meter...  I also have a Windblue 540 but from what I just read in this forum I may want to keep that to myself..... Thanks for the help.

http://www.leeson.com/Products/products/DCMotors/scrrated.html

[phil b]

Yes. The Leeson was the heart of my first generator. I got 300 watts from it. It requires a blocking diode before the battery or else, it will make its own wind even if there is none blowing.  It's posted on this board. http://fieldlines.com/board/index.php/topic,137044.msg903091.html#msg903091

[vwgtiman]

300w seems low for this motor...  I was thinking it would have been better.  Thanks for the reply!  I think for now I will pick up a set of TLG blades or Windy Nation?  The Boast Buster looks good but then again there seems to be a lot of negative things said about PMA's specifically Wind Blue.  I have a ~29' Rohn tower I was going to put up.

[CmeBREW]

Hello,     
        Yeah, I also used a Leeson 180vdc for a mill.  It did a brief 300watts in a giant wind gust once.  But that is WAYover the rated 4.5amps of the motor though. He-he   Usually just around 100watts or so in a big wind gust.  Mostly just 10-60 watts on a decent wind day. For the money, not too bad I think and a lot of fun.

 
http://fieldlines.com/board/index.php/topic,129362.0.html

But it was too low to the ground and bad up and down turbulance.
The bigger the HP and Amp rating on the Motor the more Max Watts the motor will make as a Mill.
The 90vdc motor seems to be better as a mill because they usually have higher Amp ratings than just 4 or 5 amps.  7 to 10 amp rating can make more power in the winds.

[phil b]

CmeBREW is correct.  At 12 volts, 300 watts will push the windings to their limit. I would use 36 or 48 volt battery strings if I were to use it again.

[johnl]

you should try not to exceed the original amp rating . or you might burn it out.

[Ungrounded Lightning Rod]

300w seems low for this motor...

If it were spinning at 1750 RPM and charging a 90 or 180V battery bank, 300W would be low.

But the voltage is proportional to the RPM and a good blade set has a tip speed ratio (TSR) of about 6.  That means the tip of the blade is going about 6 times the speed of the wind when it's loaded efficiently, and the longer the blade the lower the RPM for a given wind speed.  By the time you get your blades long enough that the swept area will give you significant power you're spinning a few hundred RPM, not a couple thousand, in any wind short of a huricaine.  You'll be able to drive charge into 12V and maybe 24V batteries with this thing.  But to drive 96V batteries you'll have blades so short that your mill would be the size of a lawn ornament and produce as much power in order to get up to where you're charging at all in reasonable winds.

Meanwhile, back at charging a 12V battery:  The main limit on how much you can get out of a genny is coil heating (proportional to square of current) and brush current capacity.  With a body like this motor you don't get a lot of extra cooling from the wind's airflow.  So you have to limit your current to about the rated current.

With lower voltage and unchanged current you get lower wattage.  Tough, but that's the physics.

Fortunately, something like 300 watts is enough power to be useful.