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Old 08-02-2019, 03:53 PM   #2 (permalink)
thingstodo
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Quote:
Originally Posted by kb81987 View Post
Hello my name is Nelson, I would like to build an electric motorcycle turning an alternator into an engine, and I would like to control it with the openReVolt controller. My knowledge is scarce, but I really want it, and I would like you to please guide me, maybe it is an old topic, but I would appreciate your collaboration. I haven't been able to get the openReVolt schematics from your website, it seems that the links don't work. Thank you in advance for your help.
This might be a better place to post your message

https://ecomodder.com/forum/showthre...ller-6404.html

Paul Holmes is on the forum and will likely email the information to you directly.

That said, your plan confuses me a bit. Why? An alternator is not a DC motor ... which is what you should be driving with an Open ReVolt (144A DC Controller)

I think that you need an AC motor controller to drive an alternator. But I don't think that just any alternator will work. Many are set up in a way that limits the output to under 20V.

It is my understanding that Paul's controller does not work correctly (perhaps not at all) under 24V, since the transistors don't turn on and off properly at such low voltages.

At 20V, you would need 37 amps for just one horse-power. At a nominal 12V, it's more like 62 amps per horse-power. The heat 'wasted' by an AC controller is related to the square of the current. So whatever heat you have at 10 amps, you get 4 times that at 20 amps, and 16 times that at 40 amps, and 64X that at 80 amps. I think you'd need at least 5 HP to get any sort of acceleration ... so there is a lot of heat to get rid of on your heat sinks.

That's why the voltages used on vehicles are typically over 100V, and mostly in the 400V range. It keeps the current low, and the heat low.

A DC motor that could work for a motorcycle is the kind that you'd get from an older forklift. Likely 48V or so. And you could build a battery pack from 24 - 60V, depending on the cells you choose and the space you have. That would work fine with Paul's ReVolt.

Hope that helps!
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