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Any suggestions on how to make a bike generator? Answered

I plan on making a 3 phase ac power generator on a bike my attaching magnets to the spokes and having them run by copper coils then convert this to dc current which will power a usb port on the bike, I realize I need diodes and a capacitor if I ever hope this to work but does anyone have suggestions for me? or how to calculate voltage output so I can determine the size and number of coils/magnets I will need? or how to get a steady voltage and ensure devices connected to the usb port won't be fried?



7 years ago

I don't know how many magnets you would need, but if you want to make sure your usb devices won't get fried, I would suggest to hook up your generator to a dc convertor which is hooked up to something like a rechargeable battery. This way, you could could then hook up your stuff to the battery without frying your devices.

how would I wire the battery into the circuit to make it that work? would I simply wire the generator leads in parallel with the battery which goes to the usb circuit?

I'm not sure if I understood you, but this is what I'd be doing:
I'd get a battery charger first, hook this up to the generator and try to get the batteries charged. If this works, I'd check google (or another search engine...) to see how electronic gadgets get powered while they get charged. I mean I can use all of my gadgets while charging, so there must be some kind of circuitry that allows charging the batteries while current is being drawn while the gadget is running.
I'm not that deep into electronics myself. I'm more the mechanical guy type.
I hope I can help anyways even if I can only provide some input like this to give some pointers on where to look :-)

wouldn't providing direct voltage from the output of the generator to rechargeable batteries, recharge them ? or are you saying that I need a whole other circuit just to recharge the batteries ?

I just did a quick search. I didn't read it all, but there's certainly a little more to chargers than I thought.
Here's the link:

Usually chargers are limited in their amperage so they don't overheat the batteries. Good chargers keep track of the amperage and sometimes they check on the battery temperature, too. They usually also cut off power once the batteries are full.
Just putting power to the battery could probably overload the batteries. The worst case could be that they explode or catch fire.
But now you got me more interested in chargers and power supplies than I initially wanted to be. So I may check out wikipedia to see where the differences are...

any suggestions on the electronics I should buy? are there certain diodes better than others and same for voltage regulators?

Did you follow the link? Did any of the items listed at the other end of the link demonstrate that I was being sarcastic?

I only bothered to look at the first page.