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Would this brushless motor produce electricity? Answered

 I made a bike generator but the brushes went out. Would this motor produce electricity? I will put it in some sort of protective housing. So here is the link.



Best Answer 8 years ago

I can only say "maybe"  It has three wires and I assume it has 3 coils.  A controller would be needed to run it as a motor and would turn the coils on and off rapidly to make the motor run.  "Probably" if you turn the motor you can generate a current.  It will probably be a/c and probably will only use 2/3 of the coils and only be 2/3's as efficient as it would be if you could use all of the coils.  There may be a way to connect all three wires and some diodes to use all of the coils but I'd have to do some research on that.  I've used brushless motors to fly planes before but never to generate electricity.  And I don't have one right now to test.

Now that I've done some more googling, it may be that you can connect any two wires and get one coil to activate at a time.  Depending on which type of motor it is you may not even be able to get anything useful out of it as a generator.

I would pass on this and look for something more useful as a generator.  If you use a higher quality d/c motor with brushes you won't be able to wear them out by riding your bicycle.  You would wear the bike out first.  Unless you let the motor get wet or dirty like I said yesterday.

 Could you give me a link to one that isn't too expensive? I am only 13 and I dont have much money. Right now I am using one out of a water softener and it wasn't designed to get this far. I am surprised that it is still producing anything.

First you need to figure out how much power you a) have available as torque (from wind, hand crank, etc), b) how much power you need, c)form factor, d) cost.

Especially important is how much power you have available.  If you want to make a wind turbine then you want a bigger generator based on the available wind.  You write in another question that you made a bike generator - A project I'd personally want to try is winding your own coils (out of cheap copper wire) and mounting one on the fork - then putting some powerful neodymium magnets on the wheel itself - then just make a bridge rectifier to rectify the current to dc :D

It's a brushless motor - the 3 wires are ground, positive, and 'signal' to feed back the rotational speed from an optical encoder.

What most brushless motors need is their brains ripped out and the coils resoldered just as you mention - to output 3 phase.  A tricky task at best.