If you don't mind building the controller yourself, at least partially, there's a lot of threads about the Lebowski controllers that would probably do what you want, too.
allezgrand wrote: ↑
Mar 20 2018 11:32am
how much power can one of those systems dissipate if I'm not using a battery for regen? That seems to be the biggest limitation with every system I've looked at.
Regen pretty much always goes to the battery (or other power source) in a typical EV system. That's just how regen is designed to work in all the controllers I've seen.
There are at least a few controllers with "EABS" (though not all use the term, and not all that do actually do it this way), where they actively power the wheel against it's present rotation direction, but this will *use up* power, at about the same rate it would have regained it from regen. So if you would've gotten 5% power back if you used regen, you'll waste an *extra* 5% with this form of braking. That means you actually lost 10% power over using regen for the same thing. However, it can brake down to nearly zero speed (sometimes all the way to zero), and it could be more powerful if the controller can dish out the current to do it, and it should work about the same regardless of battery level, as long as it's not nearly empty (where regen is the other way--works better the emptier the battery is, and sometimes is disabled near full to prevent overcharge).
To do anything else, you'd probably have to build it yourself. There's a lot of discussion about power-sheddng/wasting systems like Plug Braking, but generally you aren't going to have any control over how much braking force you get, unless you make it complicated and probably heavy and large like using a brushed controller powered off teh motor and running a giant resistor off the output with the throttle of that being your ebrake, or a giant variable resistor (like a 20-30lb lighting pot dimmer), etc.