This motor was the same model I used on
my standby pressure pump.
Oatley DC Motor Windmill
I built this windmill to see
if these cheap DC motors from www.oatleyelectronics.com were
any good as a wind generator.
This is the
motor I used. Its rated at 300 watts, 24 volts at 16 amps.
They are very cheap at only $36 each. The motors are very
well made and have a 9mm output shaft.
I lasercut these
parts from 3mm steel. I had planned to sell the steel
parts as a cheap windmill kit based on the Oatley motor.
The design allowed any size mast from 25mm to 60mm, tail
tube from 15 mm to 30mm, and adjustable pitch on the blade
hub.
The laser cut
plates made assembly easy. The whole project only took
a couple of hours, including making the PVC blades. I
used a blade calculator to get the correct angles for
600mm radius blades with a tsr of 7.
Results.
The blades performed very well,
achieving a high RPM for low wind conditions. Startup was
quick as the DC motors have no cogging.
But output voltage was way down
on what I had hoped for. In a 20kmh breeze, open circuit voltage
was only 5 volts, even though the windmill was going like
a bat out of hell. Surprising was the output current. When
I shorted the windmill I had an easy 10 amps, and the windmill
only slowed down slightly with this load.
So the windmill is a bit of a
failure, at this time. But I do plan to try a boost converter
that will increase the output voltage to over 13 volts for
charging. Oatley Electronics sell a boost converter/charger
kit for $14. The info on the controller IC, a MC34063, says
it will run on as low as 3 volts. Output current is 2 amps
max, but there are details on increasing this limit.
To be continued......
Well I've given up on the oatley
motor as a wind generator. I did try a boost converter, but
the results were pretty average. But these motors are great
little motors neverless for their price. At 300 watts each
a couple of these would be great on a little go cart.