Battery Regen please explain

[electricboard1]

I am just wondering what settings to put in my Vesc app for regen?

I don't have an electric brake on my standup quad thing I am building only a cable operated disc brake (non electric.)

What I need to know is does battery Regen only work with an electric brake? or does it Regen when I let off the throttle too?

On the Vesc app I have set the Regen settings to zero as I guessed it is not being used as I don't have an electric brake is this right?
Or is Regen being used when I let off the throttle and coast down hill for example?

If so what is a safe number to put in the settings for regen? Or do I leave it at zero if not being used?
my battery is a 13s 4p 48v 13ah

 

[chuyskywalker]

So, there is a way to do it, but I'm not a fan of it in most cases.

Instead of having the throttle in "current" mode, you can put it into, I believe, "duty cycle" mode. In this setup, I believe there is a way to have the VESC regen brake you down to the throttle's indicated setpoint. IE: If you have the throttle fully twisted, the VESC will push the bike to max speed. If you then change to 50% throttle, it will ebrake down to 50% speed.

However, this also means that you control speed by throttle position which feels weird to just about everyone because you only get one acceleration curve.

With "current" control no matter what speed you are at, you can roll a bit to gently accelerate or twist hard to gun it. With duty cycle, the accel curve is set ahead of time and the vesc is just trying to get from throttle X -> throttle Y value according to the curve.

 

[scianiac]

Yeah I would suggest you keep the throttle in current mode too. I think there are a few ways you can set it up though if you wanted regen with only 1 throttle. I mean adding a second throttle as a brake is better. You could set it so the throttle at rest is full brake adjusted to whatever brake current you want and the mid point where it switches to a throttle is say at 10% of the throttle's range. So basically you start twisting the throttle and it goes 100% brake > 50% brake > 0% throttle 0% brake > 50% throttle > 100% throttle. This is would feel a little nicer if you had a throttle that spins both ways and centers in the middle. I think it would be fine with a normal throttle as long as you're mostly cruising around not blipping the throttle a lot and you have the max brake set to something fairly low so it you just release the throttle it just slows you down but not too aggressively. Kinda like "one foot driving" in an EV.

I kinda feel like throttle and brake setup depends a lot on how the vehicle is being used.

 

[chuyskywalker]

So basically you start twisting the throttle and it goes 100% brake > 50% brake > 0% throttle 0% brake > 50% throttle > 100% throttle.

I wouldn't advise this. As you noted, you could only have a very small amount of regen with a setup like this. And if you didn't...well, one itchy nose later and things get dicey

There are absolutely center point throttles, which work great. You can also just wire a button between some pins to trigger "throttle is now regen" mode, which is a pretty great way to do things (since it's super easy to get a brake handle that will have the ebrake reed switch).

 

[electricboard1]

To be honest I'm not overly fussed with having Regen I just didn't want to ruin my battery by having it set at zero like I have at the moment

What I want to know is does Regen only work if I had an electric brake? (in Current mode) The mode I have is good at the moment so don't want to change it

So is it safest for my battery to just set Regen to zero?


Or should I set a different value in this setting?

 

[chuyskywalker]

To be honest I'm not overly fussed with having Regen I just didn't want to ruin my battery by having it set at zero like I have at the moment

Why do you think having zero regen set would be dangerous? (It's not)

 

[electricboard1]

Why do you think having zero regen set would be dangerous? (It's not)

That's what I figured if I set the number to zero it isn't doing anything so should be safe.
But wanted to check as i'm new to all this, just in case someone says don't do that I might blow up my house or something random

So Regen only works with an electric brake is that right?
(Which I don't have so set values to zero)

 

[Hummina Shadeeba]

if u have a direct connection between motor and driven wheel like a true hub motor u can do regen and nothing else needed. Depending on what cells you have they have a limit of what current they can be charged

 

[electricboard1]

if u have a direct connection between motor and driven wheel like a true hub motor u can do regen and nothing else needed. Depending on what cells you have they have a limit of what current they can be charged

Ok thanks, I don't have a hub wheel motor but a 1000w motor with sprocket and chain driving the rear axle on my quad/scooter

I always thought Regen was just regenerating power back into the batteries when braking or let off throttle is that right?

So should I set Regen to be about the same as my charging current which is 5amps or below this number?

Or am I better to just to leave it at zero?

 

[chuyskywalker]

Ok thanks, I don't have a hub wheel motor but a 1000w motor with sprocket and chain driving the rear axle on my quad/scooter

As long as the wheel can spin the motor, you can do regen. Which is likely the case here. Doesn't mean you HAVE to, just that you can. Which, in your case, is likely.

I always thought Regen was just regenerating power back into the batteries when braking or let off throttle is that right?

That is accurate, but it's not a defacto given in any setup. It has to be something the controller supports and is enabled.

So should I set Regen to be about the same as my charging current which is 5amps or below this number?

Or am I better to just to leave it at zero?

If you have it set to 20billion but no way to tell the controller "start doing regen" then nothing will happen. And, no, the charging current is generally very conservative to gracefully recharge the battery and extend it's life. You can often get away with much, much higher battery amps regen because it's a very brief burst of power (in most cases) and the battery will be just fine.

 

[Hummina Shadeeba]

always thought Regen was just regenerating power back into the batteries when braking or let off throttle is that right?

You could set the controller so it does regen when you let off the throttle but if u want to do a decent amount of braking ur better off with a two-way or centering throttle linked above. I use that same throttle and only use regen rear brake and have no mechanical rear brake. Sounds like you could do the same. It’s nice.

 

[electricboard1]

You could set the controller so it does regen when you let off the throttle but if u want to do a decent amount of braking ur better off with a two-way or centering throttle linked above. I use that same throttle and only use regen rear brake and have no mechanical rear brake. Sounds like you could do the same. It’s nice.

Ok thanks might have a think about that sounds good, although I quite like how it is at the moment with the throttle and brake so may just leave it as I am for now

But if say I setup Regen to roughly 5 or 8amps or something like that (or does it need to be minus number?)
and I have selected my " Current reverse ADC2 brake button" on the drop down menu, then would I be getting Regen whenever I am coasting along or freewheeling? (as the wheel is then driving the motor)
is that right?

 

[Hummina Shadeeba]

Ok thanks might have a think about that sounds good, although I quite like how it is at the moment with the throttle and brake so may just leave it as I am for now

But if say I setup Regen to roughly 5 or 8amps or something like that (or does it need to be minus number?)
and I have selected my " Current reverse ADC2 brake button" on the drop down menu, then would I be getting Regen whenever I am coasting along or freewheeling? (as the wheel is then driving the motor)
is that right?

Reverse will work as a break as well as move you in reverse I think. I think it’s another option generally used though: “Brake center..” or something

U will likely need more than that little amount of current to decently brake. You’ll need a throttle that will go backwards or it will be awkward/dangerous to use

 

[electricboard1]

Reverse will work as a break as well as move you in reverse I think. I think it’s another option generally used though: “Brake center..” or something

U will likely need more than that little amount of current to decently brake. You’ll need a throttle that will go backwards or it will be awkward/dangerous to use

Thanks but my brake is ok as it is, I don't really want to set it up to brake with Regen I'm quite happy with my standard disc brake

I just want to know if I set it up with Regen on the settings on the VESC app does this mean I would then be getting Regen into the battery when I let off the throttle or coast along downhill for example ? (as the wheel is then driving the motor) is that right?


I just need to know if I need to setup Regen at all or just leave it at zero

If I can get a bit of Regen without using an electric brake or without setting up centre throttle ect then great, I just need to know what amps ect to put in the settings

But obviously if I can't get Regen without either an electric brake and/or centre throttle ect then I guess no need to setup Regen in the app

 

[Hummina Shadeeba]

Thanks but my brake is ok as it is, I don't really want to set it up to brake with Regen I'm quite happy with my standard disc brake

I just want to know if I set it up with Regen on the settings on the VESC app does this mean I would then be getting Regen into the battery when I let off the throttle or coast along downhill for example ? (as the wheel is then driving the motor) is that right?


I just need to know if I need to setup Regen at all or just leave it at zero

If I can get a bit of Regen without using an electric brake or without setting up centre throttle ect then great, I just need to know what amps ect to put in the settings

But obviously if I can't get Regen without either an electric brake and/or centre throttle ect then I guess no need to setup Regen in the app

There’s no “electric brake” other than Regen.
If u set the Regen to a certain amount but u don’t have a two-way throttle to make it happen, you COULD use a regular throttle and adjust in the throttle setting so it would brake when coasting but to me it’s annoying or even dangerous . You’ll know if ur Regen braking looking at the real time data or you could feel it.


Just set Regen to 0

 

[electricboard1]

There’s no “electric brake” other than Regen.
If u set the Regen to a certain amount but u don’t have a two-way throttle to make it happen, you COULD use a regular throttle and adjust in the throttle setting so it would brake when coasting but to me it’s annoying or even dangerous . You’ll know if ur Regen braking looking at the real time data or you could feel it.


Just set Regen to 0

Ok thanks, sorry when I say electric brake I mean a brake which is connected to the controller to switch off the motor when braking
I don't want to actually brake using Regen I just wondered if Regen is in use when the wheel is just turning without using the throttle (ie going downhill)
So any Regen in use is actually braking force is that right?

where abouts in the real time data does it show regen? that's handy to know

 

[Hummina Shadeeba]

So any Regen in use is actually braking force is that right?

where abouts in the real time data does it show regen? that's handy to know

Yea Regen requires braking force

It’ll show negative current in real time data

 

[electricboard1]

Yea Regen requires braking force

It’ll show negative current in real time data

Ah ok thanks

Is this why we set a negative number in the Regen settings?