Anyone ever tried to implement regenerative braking?

sjpt

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who knows maybe you could do away with the mechanical brakes altogether.
If (as mentioned earlier in the thread, by saneagle?) you have a battery that can safely absorb the energy fast enough. Maybe if the battery can't absorb the energy you can absorb it elsewhere. For example: to heat the saddle?
 

flecc

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Oct 25, 2006
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One of the best things about a bicycle is the ability to freewheel for long distances without losing speed on the slightest inclines. Regenerative braking would sacrifice all that for a negligible input of energy put back into the battery. Problem is that the efficiency of the generation would be way less than the distance lost in free wheeling.
Well said, that is exactly my experience with my e-car after over six years of experience with it. The regeneration doesn't in any way compensate for the distance lost in free wheeling.

I am even more negative about the concept of regeneration on what people mistakenly think are e-bikes. They are not, they are EAPCs, Electric Assist Pedal Cycles in law and in operational fact.

As such, applying regeneration is irrational, since any gain from human effort defeats the fundamental purpose of such a machine, and any electrical gain has been shown to be not worthwhile, even on a system designed with regeneration in mind.

I'm speaking of the Magic Wheel, a hub motor designed and marketed inthe USA as part of their desire to have more environmentally friendly mobility. It failed in the market, but the design effort was not lost since Sanyo bought the design. That was the motor that Giant used later to such poor effect as I've already mentioned.

Since then Panasonic (who also make bicycles and EAPCs) bought Sanyo and have made a large scale effort to achieve wholly electrical front wheel braking with a hub motor.

They manufactured 3000 of those models for sale only in Japan in a large scale trial to prove the concept. That was back in 2008 and it's died a death since then:

Information Link
.
 
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mr_ed

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Feb 15, 2022
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Well said, that is exactly my experience with my e-car after over six years of experience with it. The regeneration doesn't in any way compensate for the distance lost in free wheeling.

As such, applying regeneration is irrational, since any gain from human effort defeats the fundamental purpose of such a machine, and any electrical gain has been shown to be not worthwhile, even on a system designed with regeneration in mind.

Since then Panasonic (who also make bicycles and EAPCs) bought Sanyo and have made a large scale effort to achieve wholly electrical front wheel braking with a hub motor.

They manufactured 3000 of those models for sale only in Japan in a large scale trial to prove the concept. That was back in 2008 and it's died a death since then:

Information Link
.
Thanks for the link, that’s interesting. They quote that the regen increases the range from 90km to 125km, very impressive… even if taken with a pinch of salt.

There still seems to be some misunderstanding…I am saying the regen is only active when you are braking…the bike will freewheel same as any other bike if you're not touching the brake lever.

I suspect your car could be set to behave like this too…it probably has a 'one pedal' mode where fully off the throttle activates the regen braking but somewhere on partial throttle will be effectively freewheeling with the motor consuming no power.

I'm not going to keep going on about it… but the laws of physics are there to make use off. There is free energy available when braking…if you can harness it without weight penalty to do so then it’s a positive thing.
 

flecc

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Oct 25, 2006
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There still seems to be some misunderstanding…I am saying the regen is only active when you are braking…the bike will freewheel same as any other bike if you're not touching the brake lever.
I had fully understood your meaning, but am convinced by the long history of the failures of the attempts already made that there isn't enough recoverable energy to make it worth bothering. I'd thought at the time that Panasonic, as an EAPC pioneer, of all people could make it work well enough, but clearly they don't seem to have ended up convinced.

I suspect your car could be set to behave like this too…it probably has a 'one pedal' mode where fully off the throttle activates the regen braking but somewhere on partial throttle will be effectively freewheeling with the motor consuming no power.
Yes it has that selectable mode but I've found it wasteful and a little unpleasant in practice. I prefer my own skills in staying in the minimal use region.

I'm not going to keep going on about it… but the laws of physics are there to make use off. There is free energy available when braking…if you can harness it without weight penalty to do so then it’s a positive thing.
There must be some of course, but a worthwhile recoverable amount seems to be very elusive, coming only at the cost of spoiling the ride in other ways.
.
 
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saneagle

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the bike will freewheel same as any other bike if you're not touching the brake lever.
That's the bi8t you're misunderstanding. It won't. There are no motors with a cable actuated clutch.

When you have an electric car or motorbike, the only way to move is with the motor or by using gravity. A bicycle is moved by pedalling, but that makes people get aching legs, so they want an electric motor to help them. If the motor is engaged all the time it needs to be powered, otherwise it'll create drag. The drag will cause you to have to use more energy to pedal at the same speed, or you can use more power from the motor to overcome it, which cancels out the gain you got from your regen.

As I said, like you, many manufacturers thought it sounded like a good idea, so they tried it, but the only people who though it was any good were those that didn't want to pedal much. The word soon got around. People stopped buying those bikes and they were discontinued by the manufacturers. They were all over Indegogo and Kickstarter about 10 years ago, but I don't believe any are still in business, and I haven't seeen any new ones for ages.

the laws of physics are there to make use off. There is free energy available when braking…if you can harness it without weight penalty to do so then it’s a positive thing.
It's the sort of thing university graduates used to come up with after studying about energy saving and green policies, but they have no real-life experience.Unfortunately, there are many laws of physics and when you design stuff, you soon figure out that for every upside, there's a downside.
somewhere on partial throttle will be effectively freewheeling with the motor consuming no power.
Maybe I need to go back to engineering school because I always thought that opening the throttle a little bit causes the motor to use a little bit of power. What would be the point of opening it a bit if it did nothing. You might as well leave it shut.


So, you asked for opinions. We gave you advice based on actual experience. You don't like the answers, so we must be wrong. Is that it? We could have sat here silently, while we exchanged personal messages between ourselves and had a good snigger at your expense.
 
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Ghost1951

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This concept reminds me of a 'brilliant' idea I had when I was about twelve. We had been looking at electric motors and dynamos in a science lesson at school, and I was thinking about the way a dynamo is just like a simple direct current motor while I was bored to death on my paper round.

Thinks me: I could connect the shafts of two electric motors together so they both spun together when one of them had power applied. I would wire them up with switches. To start off, I would switch on a battery to spin up one of the motors, and when it got to full speed driving the other one by its shaft, I would switch out the battery and switch the wires of the driven motor (the dynamo) to the wires of the driving motor and marvel of marvels, the thing would sustain itself in complete defiance of common sense, and I would have a perpetual motion machine.

It was bound to work. Wasn't it brilliant? Well - it seemed so to my barely twelve year old self.

I understand that most schoolboys think of this scheme at some time or other.

Mind you, there is one very long steep hill I often descend with about four hundred vertical feet of descent which might yield a useful amount of energy which is currently wasted in wearing out my brake pads. But any other downward slope I really want the free ride of freewheeling. On those slopes regen braking would just waste the valuable free miles. You know you are driving efficiently when you almost never have to replace brake pads and discs. Anticipation is all in fuel efficient driving and riding.
 
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saneagle

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Thinks me: I could connect the shafts of two electric motors together so they both spun together when one of them had power applied. I would wire them up with switches. To start off, I would switch on a battery to spin up one of the motors, and when it got to full speed driving the other one by its shaft, I would switch out the battery and switch the wires of the driven motor (the dynamo) to the wires of the driving motor and marvel of marvels, the thing would sustain itself in complete defiance of common sense, and I would have a perpetual motion
That's what I do to power my house. It's free energy. All you need is two washing machine motors, some brackets and a belt. There are loads of YouTube videos on how to do it like this one:
 

Sturmey

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..........Mind you, there is one very long steep hill I often descend with about four hundred vertical feet of descent which might yield a useful amount of energy......
Just some theory and ballpark figures. Assuming you and your bike total weigh 100kg, you are talking a potential mechanical energy figure of about 33Wh or perhaps about 20-25Wh electrical if we are allowed to assume 70 to 80% motor/controller efficiency. If you come down that hill in five minutes, you could be dumping about 6 to 7 amps back into the battery for 5 minutes = .5Ah approx. (36V) Much more if you come down much quicker. You will be generating extra heat into your system going downhill rather than letting your battery and motor take a well deserved rest and cool down on downward slopes, (which is often desirable when cycling in the hills).


58065
 
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AGS

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You need to configure the controller to keep the regen phase current at a sensible level so it doesn’t damage the battery.

I changed my regen phase current from 30 amps to 50 amps yesterday to improve the braking ability, but I had second thoughts about it today so changed it back to 30 amps to protect my battery.

I only use regen at the brake levers and disabled it at the throttle. It’s horrible when regen kicks in when I come off the throttle. It feels like the bike is controlling me rather than me controlling the bike.
 
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Ghost1951

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That's what I do to power my house. It's free energy. All you need is two washing machine motors, some brackets and a belt. There are loads of YouTube videos on how to do it like this one:
Yes, I've seen them, and the ones where a spark plug and some wires can power a light bulb. I can't imagine why anyone bothers with paying electricity bills or even worse, shelling out for solar panels.

People have actually sent me links to these videos asking how it works...... Unbelievable.
 

AGS

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I built a free energy generator from two washing machine motors that I got from the recycling centre. I use it to run my cyclotron that I made from an old tumble drier.

I‘m using the cyclotron to produce radio isotopes for my nuclear battery to power my e-bike.

The most expensive part was the lead to wrap around the tumble drier, but fortunately I was talking to a couple of pikeys down the pub and they managed to get hold of some second hand lead for me really cheap.
 
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saneagle

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Yes, I've seen them, and the ones where a spark plug and some wires can power a light bulb. I can't imagine why anyone bothers with paying electricity bills or even worse, shelling out for solar panels.

People have actually sent me links to these videos asking how it works...... Unbelievable.
Unfortunately, I bought my solar panels before I built the generator. I'm building a new ebike project at the moment. It's going to have a big rotor that turns in the wind made by my forward motion. It will drive a 250w generator that will charge my battery, so I'll never run out of power. It'll be the ultimate range electric bike.
 
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sjpt

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Can one use solar panels for regeneration? Push in some power and generate some heat to warm up the sun?
 

saneagle

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Can one use solar panels for regeneration? Push in some power and generate some heat to warm up the sun?
It's easier than that. You just connect the output to a load of light bulbs pointed up at the sky.. I've been doing it since I built my free energy generator. They said we had the hottest May ever this year, so it might be working, but May seemed pretty cold to me compared with 1975 and 1976 plus most years since except this year. Maybe the light bounces off the ionosphere and lands in Africa because I haven't got the angle of the lights right.
 

jamesporritt

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You need to configure the controller to keep the regen phase current at a sensible level so it doesn’t damage the battery.

I changed my regen phase current from 30 amps to 50 amps yesterday to improve the braking ability, but I had second thoughts about it today so changed it back to 30 amps to protect my battery.

I only use regen at the brake levers and disabled it at the throttle. It’s horrible when regen kicks in when I come off the throttle. It feels like the bike is controlling me rather than me controlling the bike.
Is reducing the regen charge rate of the battery using supercapacitors feasible?
 

Ghost1951

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Unfortunately, I bought my solar panels before I built the generator. I'm building a new ebike project at the moment. It's going to have a big rotor that turns in the wind made by my forward motion. It will drive a 250w generator that will charge my battery, so I'll never run out of power. It'll be the ultimate range electric bike.
Those model aircraft chaps should utilise that idea. They could fly those electric planes forever by doing that.