Does regen work more with low voltage battery?

I just peceived that my regen doen's seem to work awhen i'm running at 86V.. :|

and if i remember, when i drop it to 48V, or 33V, it seem to work!

My 5305 is high winding motor so it should be more efficient on regen right?

I'm just confused because the regen on my ebike seems not to work at 86V...

I also would like to try to use 6 powerfull bridge diodes on teh 3 phases of the motor combiend with a high amp relay to switch braking regen.. A123 seems to be able to hold that...

Fechter, ypedal, safe?

any opinions?

The higher the voltage you run.. the faster you need to go before you create power..

Lift the wheel off the ground and know your No-Load speed at full throttle..

You need to get the wheel moving faster than this number before the motor will generate any usable current.. !

Unless i did not understand your question properly ??? :?

Right, unless you're using a regen controller that can boost the motor voltage, you won't get any regen until the bike is trying to go faster than the no-load speed.

At a higher voltage, the no-load speed is higher. If you switched your packs in parallel at a lower voltage for braking, then you would get some regen.

The controller already has a bridge of diodes built into the FETs.

If you had an external 3 phase bridge, you could dump power into a resistor or some kind of dc-dc converter that will boost it enough to go back into the batteries.

If you want to use a resistor, you don't really need a bridge.

Thankd guys,

that confirm my understanding about that..

a DC-DC (low to high V) could be interesting!

Fechter, you said that some controller have already a circuit built in to compensate or "boost" the V at low speed when regen?

wich one?

In essence, any controller with true regen will do this. The Kelly controller is one example.

It uses the winding in the motor as an inductor in a boost switching setup. Even though the back EMF of the motor is less than the battery voltage, by PWM'ing a short across the windings, the voltage spike from the field collapse will be in the hundreds of volts, which gets circulated back to the battery through diodes.

We must have discussed this in the regen addon thread, but I'll ask again here: Why isn't that spike of hundreds of volts a problem for the main controller?

The spike is circulated to the batteries, which clamps it to the battery voltage + voltage drop in the diodes. If the batteries were open (blown fuse, etc.) You could overvolt the controller and blow it very quickly.

And as always, when you say "diodes" in the context of a brushless controller, you mean the FETs acting as a diode bridge?

lazarus2405 said:

And as always, when you say "diodes" in the context of a brushless controller, you mean the FETs acting as a diode bridge?

Click to expand...

Correct. The body diodes in the FETs act like a 3 phase bridge. You're learning...