ACTUAL home-brew EV regen braking

[ev59rag]

Originally Posted by watt-a-mezz

If I had an alternator with an external voltage regulator, (like a Ford product), and I do not use the regulator,and I use GND, wire Field to 12v from the brake pedal switch, Stator not used, and Battery turns into HV wire going to main pack, would I have a simple form of regen braking, or a smoking mess? I will be using a 96v battery pack(8 12v). Also, if you do use regen, do you measure in volts or amps? Sorry it is so ong, but any feedback would be helpful. Take care, Watt

Maybe I can answer you with my limited knowledge on the subject. I believe, its not going to be as simple as that. By removing the regulator, you will then make the current AC (thats why they call it alternator). You need at least a big rectifier diode to make it DC.

Correct me if Im wrong. See, if its a dc then we usually call them generator (like the orig air cooled vw's). But going back to the alternator, if you remove the regulator without the rectifier diode, whats stopping it from turning on its own? feeding power off the pack. We call it also as "keeping it from running away" term in the wind turbine community.

I believe that you need the rectifier diode to make it back to DC. I believe that diodes does not limit your output voltage but just rectifies it.

FYI, I have a this alternator for my wind turbine, and i think im putting it down and use it on my ES-31C motor instead.

From what I learned from the solar/wind community that these devices will give you whatever voltage your pack requires (of course with the right rpm). They call it self-regulating because of the battery. So even if you see 150 open volts, once you connected it to a 12 volt battery, it will go down to whatever the battery requires, in my case, from 12 volts or less (charging) then goes up to 14.5 (fully charged).

Also remember that these are like dumb chargers, they will keep on dumping voltage to the batteries even if its fully charged. So you need a dump controller like this one to dump all excess to another source.

Cesar

[MetroMPG]

There may be a bit of confusion regarding "regulator" vs. "rectifier". Removing/modding the regulator alone won't change the output to AC.

[ev59rag]

You are correct. But from what Im using, my alternator is a 3 phase AC.

On a side note, (stupid notion) I thought thats why they call it alternator, its because its alternating current????? Based on this wiki, most modern alternator have a built in rectifier diodes to convert it to DC, and a built in regulator to regulate the output voltage.

Thats why its common practice for those people who converts their alternator to make it wind turbine (successful or not) removes the voltage regulator (and sometimes rectifiers because they are built in to regulators) and just add rectifier diodes to make it DC. Like this one...

[watt-a-mezz]

Hi, and thank you both for your input. I am in the process of getting the last bits and pieces together for my 88 Nissan, and after I am able to drive it, the idea was to try different things to improve range. Because of some long 10% grades going into the next town, I thought regen might help. Will keep researching and posting. BTW wind tubines are also something I would like to try for a small charging station. Thanks again, Take care, Watt