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In a dc setup if I turn a motor I can generate energy. Would it be possible to use a manual transmission setup to engine break on a hill and send the generated power back to the battery it would be simple regen breaking.
 

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Yes, this will work. A DC motor is more difficult to use in this way though -- there are issues with brush advancing, and DC controllers with regen are less available.
 

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Hi
Most DC motors used in EV's are series wound - this makes regen nearly impossible as its not "stable"

You start to re-gen and the current goes out of control - its a strong positive feedback process

Its possible that with the latest and fastest controllers they MAY be able to handle it
 

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Regen hardly has any impact on range. It's not the magical thing people think it is. You're getting a few percent extra range in city driving conditions.

Surprised anyone's still going DC, what with all the cheap-as-scrap AC options available now thanks to Johannes and Damien and friends.
 

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Regen hardly has any impact on range. It's not the magical thing people think it is.
My Bolt EV regens going down the mountain...I've picked up 34 miles of extra range for the day at times, and I only charge to 85% to give myself a "hill reserve".

Yes, you give much of it back going back up the hill, but for long trips, it lets me pick a further recharge station.

I very rarely use the friction brakes...

Having had it now, anything without regen is a non-starter....my builds now will have to have single-pedal driving, which adds fun to managing the brake lights as a "small" detail.
 

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As remy_martian's example illustrates, the degree of benefit of regenerative braking depends on terrain (more useful with more grades), how much you change speed (for stop-and-go it can be important, but at constant speed on a flat highway it's not), and driving style (if you brake so hard that you mostly use friction brakes, or brake so little that you are just coasting down in most cases, regen doesn't do much).

No manufacturer would build a modern EV without regenerative braking, but it costs them nothing to include it so the decision is easy.
 

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Just a question on regen and controllers. If you have a controller that doesn’t support regen, I would have thought it would be possible to use a fairly simple circuit to do this, comprising of a step up dc converter if its a dc motor, a rectifier if its ac, and a regulator and/or chanrge controller, obviously switched on by the brake pedal and isolated when the motor is being driven. Would have thought it is the same as building any other generator. Has anyone tried this?
 

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If you have a controller that doesn’t support regen, I would have thought it would be possible to use a fairly simple circuit to do this, comprising of a step up dc converter if its a dc motor, a rectifier if its ac, and a regulator and/or chanrge controller, obviously switched on by the brake pedal and isolated when the motor is being driven. Would have thought it is the same as building any other generator.
The problem with a series DC motor is that the field current is also the stator current, so you can't control the field to control the output as you would with a generator.

I think that any AC controller which doesn't do regen is a good candidate for the electronic waste bin, rather than being part of a more advanced system.
 
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