Using my Swytch AKM motor as a generator

[mta102]

Hi all,
I want to add regeneration capability that I can switch on/off on demand for downhill braking.
I tried to connect my Swytch AKM motor to a bridge rectifier. It generates current when spinning backwards (where there is considerable drag), but not forwards (where there is minimal drag).
I assume this is because of the freewheel.
I have considered a dynamo that is used for lights, but at 3-6W, I am not sure of its utility for regen braking or recharging the battery.
Any other ideas on how I might acheive my objective without replacing the motor?

 

[saneagle]

Hi all,
I want to add regeneration capability that I can switch on/off on demand for downhill braking.
I tried to connect my Swytch AKM motor to a bridge rectifier. It generates current when spinning backwards (where there is considerable drag), but not forwards (where there is minimal drag).
I assume this is because of the freewheel.
I have considered a dynamo that is used for lights, but at 3-6W, I am not sure of its utility for regen braking or recharging the battery.
Any other ideas on how I might acheive my objective without replacing the motor?

Take the side off the motor to get at the clutch. Weld or glue the inner part to the outer. Reassemble the motor, then see how much you enjoy the regen experience. Try not to weld it too well because I guarantee you'll want to unweld it before you get to the end of the street.

Normally, the idea of an ebike is to help you ride your bike by using the energy in the battery to add to the energy you put into the pedals, not put extra energy into the pedals to charge a battery.

By way of example, an average commuter type cyclist puts about 100w through the pedals. To charge your 500wh battery at an efficiency of around 70% would take around 7 hours pedalling at 100w, but that's without using any energy to move the bike. If you wanted to do it while travelling, you'd have to pedal continually at 200w, which is about what an average club cyclist does. Pedalling at that rate for 7hrs would fully charge the battery, then you could relax for the next 30 miles, while you pedal gently with assistance again for about three hours.