Gains from regen braking

[Alansurfer]

Regen isn’t just to slow down to a stop, best method for efficiency is to feather the throttle to maintain a speed on a downward slope or reduce speed slightly to use a little regen. Long downhills though it’s better to coast, you can coast by adjusting the throttle to keep the power meter at 0. My Nissan Leaf used to keep a record of the regen and it was always surprising how much it accumulated over a month and a couple of thousand miles.

 

[johnb80]

Regen isn’t just to slow down to a stop, best method for efficiency is to feather the throttle to maintain a speed on a downward slope or reduce speed slightly to use a little regen. Long downhills though it’s better to coast, you can coast by adjusting the throttle to keep the power meter at 0. My Nissan Leaf used to keep a record of the regen and it was always surprising how much it accumulated over a month and a couple of thousand miles.

At last, someone that knows the throttle is not an on/off switch

The number of times you read 'regen is too strong, I dont like it', KEEP YER FOOT ON THE PEDAL

 

[Alansurfer]

Set to full strength regen and using the throttle to regulate the strength from coast to full gives far more control. I’ve been driving and riding electric for over 10 years and build my own stuff too including battery packs. Converted my sailboat to electric drive with hydro-regen over the prop when sailing, not used to slow me down like the car but get some energy back and every little helps.

 

[Alb]

Converted my sailboat to electric drive with hydro-regen over the prop when sailing

Had an upscaled version of this implemented as a means of managing rapid slow down on my last project before retirement.
Four 20MW propulsion motors in regen mode dynamically braking a 65000 Tonne vessel with energy dumped into a resistor bank rather than recovered.

 

[Tim Green]

And what power did you "recover" into the resistor bank? Could you use it to heat water or something? Even at 1% regen thats a lot of heat! Did it work to slow the ship quicker? Did you use standard screws?

 

[Alb]

Can't remember the rating of the DBR I'm afraid. It was not cost effective to recover the energy but if that were the aim it would have been done directly through the PWM Drives powering the motors. The resistors were water cooled so the heat generated ends up in the ocean. It played an essential role in enabling the ship to meet its crash stop requirements. I've attached a picture of one of the propellers below

 

[Tim Green]

I think I recognize the blue jackets! A friend of mine (living in Dorset) is closely involved in screws of that sort. They look to be variable pitch? Can that be trimmed for regen?

 

[Alb]

It's fixed pitch but each blade is individually bolted to the hub and can be adjusted in pitch if required.