How pure is "pure"?
When I spin my motor I increase the speed in few seconds, keep the hair dryer at (relatively) constant distance to the motor's propeller for few seconds and then turn the dryer off.
I think in real life that might be some wind bursts but the reason why I choose the vertical axis turbine is exactly the fact that in the target area the wind speed is usually 1-2 m/s.
It is something confuse in all this. Why the Joule thief cant work on variable voltage? Or, at least, how much variability is OK?
If I mount a capacitor (as advised) to the motor, then some sort of equilibrum between the current sent to cap and the current sent to Joule could be achieved. That is my understanding, but I may be wrong.
A joule thief can offer higher voltage even when closing and opening the circuit by a push button. Why it cant do the same when the voltage varies with the wind speed?
@mauried
Think to the project as a sort of "close garage challenge": I have only usual components: a handful of diodes and transistors, resistors, wires. That is fun and is also learning.
I have a toy motor in my hand. No Hall sensor or similar. How can I measure the spinning speed? We have to imagine a method. What I have in mind is to place two wires ringshape near two sides of the motor and measure the current by an multimeter. Or use some sort of optical method. Lets be innovative and imaginative.
Good engineering is simple engineering. Exceptional engineering is fun engineering. :-)