Tape motor wind turbine build, 500 watts....

[Jon Miller]

Hi all,

Today I woke up and decided today was the day I was going to build a wind turbine out of this tape motor I have had for ages.

The motor in question is a 60volt, 1.2ohm, 10amps, motor measuring 23cm long.

Initial test using a cordless drill at 350rpm, volts = open circuit 13.5, dead short amps unknow

I headed of down to BnQ for some angle costing the sum of £11.26, expensive but where else do you go on a Sunday?

I welded up a simple frame out of the angle to hold the motor and I plan to get some U clamps to finish the job of.

see pics:

I have a couple of questions to those in the know.

I have plans to use this on a 24 volt system.

Ohms law. 24 volts / 1.2 ohms = 20 amps

20 amps x 24 volts =480 watts.

I now need to make some blades to power this baby, what size am I looking at here i know cut in is around 300 - 350rpm but i do not have a means of measuring this accurately.

Thanks for the help.

Jon

[Flux]

Your cut in at 12v will be about 350 rpm. If you want to use it at 24v it will be 700 rpm. I assume you don't intend to do a speed increase.

Assuming your resistance is 1.2 ohms then for 20A into 24v you will need 48v oc that equates to 1500 rpm.

For 400W at that sort of speed you are looking a something like a fast 4ft machine in a gale. Larger blades sizes are not going to get you up to that sort of speed.

I am not sure that is a reasonable prospect for 24v. better suit a 5ft machine at 12v but I wouldn't expect you to see the 400W in normal winds. A fast 6ft blade might give better overall power if you don't want the very best low wind output.

Flux