Please Help me Understand Regen.

[Joaquin Suavve]

I presume that it is some type of system that when engaged by "backlashing" the drive of the electric motor when "off throttle" to charge the battery system by resistance.

How efficient is it?

If it is such a great idea, than why are there not throttles that act with a twist backwards to act like like a brake?

 

[gromike]

The motor becomes a generator if it is driven.
What limits efficiency, outside of mechanical and electrical losses, would be the batteries ability to absorb and store the regen energy. At least in my way of thinking.
There are double twist throttles out there that do braking one way acceleration the other, along with a controller that can accept it.
On my Ryvid emoto, rolling off the throttle, or braking triggers regen.

 

[neptronix]

I can't think of any reason it wouldn't be close to the efficiency of driving the motor forward.
Yeah, battery efficiency is the limit. Most batteries can only charge 1/2 or less at what they can output. If you start exceeding that, you can substantially increase battery wear and see reverse sag, and that's bad news.

There are throttles that act like you describe. I find a brake lever to be a lot better.

 

[stancecoke]

If it is such a great idea, than why are there not throttles that act with a twist backwards to act like like a brake?

They are existing, I've build a wheel chair puller with a bidirectional throttle. The vehicle works in full four quadrant operation, so you can accelerate and brake in forward and in backward direction. But of course you need a direct drive or a geared motor without freewheel to do breaking/regen

Brushless motor controller with reverse

:roll: Good luck with your project. Oh dam Wolf my bad I don't know how I misses that link idea way back in the post thank you I'm using it in my keyword search now. Also one member just posted down below a link .. kit idea that looks great may may not work, but my concern is I want to...

endless-sphere.com

regards
stancecoke

 

[Mclewis1]

I presume that it is some type of system that when engaged by "backlashing" the drive of the electric motor when "off throttle" to charge the battery system by resistance.

How efficient is it?

If it is such a great idea, than why are there not throttles that act with a twist backwards to act like like a brake?

Throttle option - Bidirectional Twist Throttle with HiGo 3 pin Connector Plug
Proportional eBrake - Ebrake Levers with Analog Output & Level Shifter-4 Pin HiGo, Right Side

Currently both options are offered to be plug n play with Grin's Superharness but can be adapted for use in most other controller/display setups (you'd likely have to cut ends off and perhaps do some work to match voltages required).

There are other similar products around, you'll just need to be careful of the specs (or lack thereof) to ensure compatibility with whatever controller/display combo you have.

 

[scianiac]

The more important question as I assume you are considering trying it on whatever build you have with a LR small block on so what is the drive system like on that bike. Is it a single speed drive from the motor to rear on a hardtail frame? If so that would work nicely, if not there are other issues depending on the setup. Most suspension frames will have some issues although LR has been experimenting with dual tensioners but that is still not perfect.

 

[offGridDownUnder]

by "backlashing" the drive of the electric motor when "off throttle" to charge the battery system by resistance.

Not so sure what you are thinking by using these words (and so few of them) but I'll take a chance and assume you mean these literally. Someone else might benefit.

No.

Many electric motors function as generators when driven mechanically at their shaft, and with the right wiring and other parts (a battery and usually a controller circuit) they will charge a battery.

"resistance" is not the mechanism. Any circuit made of real materials (copper, carbon fibre, aluminium) will have resistance but that is no part of the mechanism that leads to electricity to put into the battery.

The motor is a generator. That's all. There is nothing arcane about it.

 

[A-DamW]

If it is such a great idea, than why are there not throttles that act with a twist backwards to act like like a brake?

Couple more bi-directional (regen) throttles:
dyol
Spintend

You can also:
-Use a second normal throttle connected to adc2, mapped as brake. (I use this method, very nice proportional control)
-Use a momentary push button connected to adc2 mapped to reverse the main throttle for braking. (I have not tried this yet... soon™)