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Adding Regen to DC? Not for range...

8007 Views 29 Replies 12 Participants Last post by  Overlander23
I live in the foothills of SoCal and I notice that while I drive any of my ICE vehicles, auto or stick, I use downshifting to control my speed. I do this for traffic or hills. Since I am seriously considering a DC electric conversion, I would like some resistance from the drivetrain when operating under zero throttle. I would use the transmission to select the amount of drag, lower gears for more deceleration, just the same as the ICE vehicles. My intended pack voltage will probably be 156V (48 lithium cells). I know that a controller will be needed to prevent overcharging, the max regen (charging) voltage should be no higher than 168V - 170V.

Since I typically care about efficiency, I don't want to just drag the brakes all the way downhill or approaching a traffic signal (I don't do that today in my Suburban, Fit, Insight or 914-V8). So for the sake of driveability, how can I get the conversion to feel more like a regular car? I'm not impressed with the AC systems that are available today, none seem to match the power of a WarP9 for a similar weight.

I've spent a day reading way too many threads that barely touch on the subject (please don't mention perpetual motion) and the only practical advice that I mined from all that has been the guy with the S-10 that rewound his own alternator. I was hoping that I could buy most of the components necessary to build a similar finished product. I'm not looking for a kit, just some sources for the major components. I'm also open to alternative strategies. Anybody else headed down this path before?

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Seems like a rewound alternator, or DC generator head, are about the only options. You could also stack an AC motor on top of the DC motor for extra power and built in regen, if it ran the same voltage, expensive though.
Are there Sepex controllers available that run to 144-156V?

Not that I've ever heard of. Saying "get a sepex" sounds good, until you actually try to do it.
Just a suggestion, but have you considered dropping your system low enough to run a sepex or AC motor like JRP3? His Fiero has fully functioning regen setup and seems to have enough pow - well, I'll let him tell you how it runs:)
I do love my system :D Just put it in second gear and go, all the way to 65 mph. Doesn't have the off the line pull of a DC series motor but it's plenty for normal driving, and there is always first gear if I want a quick shot from 0-35 mph.
EV deceleration is also gear dependent, you won't get much in 4th or 5th, another reason I do most of my driving in second. The nice thing about regen is the way you can modulate the intensity with the accelerator pedal. I can hold the pedal neutral for zero regen and coast, or I can use varying amounts of regen depending on what I need. Takes a little getting used to and some practice but I like it. Adds another dimension to driving.
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