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Discussion Starter · #1 ·
So I wired a wind generator to a controller, battery, inverter and can power a battery and light a 40 watt bulb using a hand crank I made. Yippie for me. But the thought can I connect it to the front of my motor and regen 144V back when braking? How would I connect it to the 144V pack without overcharging, or whatever?

The small generator has diodes in it, produces power in either direction, voltage goes up with speed, and I can bolt it to the front of the motor, connect a brake switch, wire all that up, but would I just connect it to the 144V and assume it can't blow up the pack, or do I have to create some kind of controller? Just hand cranking it shows me how much energy is required just for 40 watts!

I have an RPM guage, so if I had to limit the regen speed, I could do that.

Want to test this, but don't want new parts! Any ideas?
 

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or do I have to create some kind of controller?
I'd say so. :)

Not sure what you expect, but say you actually could do 1 kW of generation. During a 10 second stop, that would be 10,000 watt seconds, or joules. Which is 0.003 kWhr. So if you did 100 stops diving on a charge, it would generate 0.3 kWhr. And that does not include any charge/discharge efficiency of the battery. So you'd likely see about 0.1 to 0.2 kWhr additional to the 10 to 20 kWhr of a typical EV battery. That would give you about a 1% increase in range. Oh, and then you have to account for the increase in mass in your vehicle for the generator and the power required to turn it when you're not generating. Net result, you'd lose range or at best, break even in my opinion.

Regards,

major
 

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Discussion Starter · #3 ·
So... if I make 2 stops on a typical 40 mile run, not worth it?!!! I thought it would help with my weekend city driving, looks like it isn't worth the effort!

Thanks!
 

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Why does not your motor/ controller give regen? That way you will have no extra weight added, and no extra losses.

My motor/controller setup gives me regen as standard, but I have a sepex, have heard it can be hard with series?
 

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F16. I for one, think it is worth doing. Perhaps not so much for the regen power...unless you live around a lot of, or long, hills. More though, for the free braking power. REad what Wayne did here. . . http://www.waynesev.com/ I've spoken to him and he thinks it was worth while. He can actually break the wheels loose if he uses it with higher motor rpm and a strong field. Wayne re-wired a large truck alternator and used larger diodes to handle the power as I recall. I plan on doing some similar things. I also considered a wind generator .... for a while. I discarded the idea though, because of the permanent magnet field. I think that having a sep ex field allows you to fine tune it and even change it according to some other things (road conditions perhaps).... you could use an electric brake controller... perhaps. Consider using an electric clutch and mount it on the front of the motor, to be engaged when you want regen. This way, you don't turn/drive anything unless u regen. Yes, I know it's not AC and automatic... but,...it's kinda kewl.
Food for thought, I like it.... :D
 

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F16. I for one, think it is worth doing. Perhaps not so much for the regen power...unless you live around a lot of, or long, hills. More though, for the free braking power. REad what Wayne did here. . . http://www.waynesev.com/ I've spoken to him and he thinks it was worth while. He can actually break the wheels loose if he uses it with higher motor rpm and a strong field. Wayne re-wired a large truck alternator and used larger diodes to handle the power as I recall. I plan on doing some similar things. I also considered a wind generator .... for a while. I discarded the idea though, because of the permanent magnet field. I think that having a sep ex field allows you to fine tune it and even change it according to some other things (road conditions perhaps).... you could use an electric brake controller... perhaps. Consider using an electric clutch and mount it on the front of the motor, to be engaged when you want regen. This way, you don't turn/drive anything unless u regen. Yes, I know it's not AC and automatic... but,...it's kinda kewl.
Food for thought, I like it.... :D
I knew I saw that somewhere I have been on another thread and thought doing the regen to stop the problem of ---well here is the thread : I will let it speak if you have not seen it...

http://www.diyelectriccar.com/forums/showthread.php/warning-evs-owners-use-clutch-39000.html

read to the end to find the blurb about the things you mentioned !!!

:cool:
 

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I knew I saw that somewhere I have been on another thread and thought doing the regen to stop the problem of ---well here is the thread : I will let it speak if you have not seen it...

http://www.diyelectriccar.com/forums/showthread.php/warning-evs-owners-use-clutch-39000.html

read to the end to find the blurb about the things you mentioned !!!

:cool:
hmm interesting issue. Perhaps a few things going on there. . . that need addressing. As for "motor braking", Wayne did implement this partially for the ability to bring motor rpm down to improve/shorten shift times.... another benefit perhaps....
 
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