3 speed electric bike

[kriskros]

anybody know anything about World Wide bike... advertising three speed internal planetary gear...... with regen... 500watt motor with 36v lifepo4 battery $599.00 total... how can you have a 3 speed planetary?? would this mean no regular shifter system required??? [not likely] but what?? advertised on ebay under lifepo4 batteries

 

[louispower]

Hi, that is for high low and midieum speeds, nothing to do with the planetary gear.

planetary gear inside the motor couldn't be 3 speeds, it is with a fixed ratio.

 

[dogman dan]

Most gearmotors freewheel, so how can it have regen? Of course the controller could have regen, but a motor with an internal freewheel wouldn't make any current.

 

[louispower]

Most gearmotors freewheel, so how can it have regen? Of course the controller could have regen, but a motor with an internal freewheel wouldn't make any current.

Very professional

Its regenerative braking and both EABS is activated by the controller, at the moment the cycler brakes the bike the controller will detect this and generate a “reverse voltage ” higher than the battery voltage to charge the battery, this happens only at the moment (several seconds) the cycler starts to brake the bike. The EABS also starts to brake the motor, so even if the bike is without mechanical brake it will be also braked. (Of course we donot recommend this).

Why we combine the gearmotor with regenerative. First reason the regenerative does works when starting to brake although it lasts only several seconds, ands the EABS increases the driving safety; Second reason is nobody will cycle his electric bike(with non-freewheeled motor) to charge the battery, the resistance will make this impossible; last, the freewheeled motor lets the driving more esaier when battery is out of power, compared with normal motor.

 

[Drunkskunk]

Something about this doesn't sound right.

if you have a freewheel, the the motor isn't turned by the wheel when not powered. As soon as the motor's rpm drops below the rpm needed to keep up with the wheel, the freewheel lets the bike wheel turn freely, without being engaged to the motor. Regen needs there to be no freewheel, and keep the motor engaged to transmit your forward momentum to the motor.

Nothing stopping a company from sticking a regen controller on a freewheel geared motor I suppose. it wouldn't hurt anything. And I imaging it might be able to grab a watt or two from the rotating mass of the motor as soon as the freewheel engages. I wouldn't call that true regen. its not recapturing the energy from the bike and rider.

 

[louispower]

Something about this doesn't sound right.

if you have a freewheel, the the motor isn't turned by the wheel when not powered. As soon as the motor's rpm drops below the rpm needed to keep up with the wheel, the freewheel lets the bike wheel turn freely, without being engaged to the motor. Regen needs there to be no freewheel, and keep the motor engaged to transmit your forward momentum to the motor.

Nothing stopping a company from sticking a regen controller on a freewheel geared motor I suppose. it wouldn't hurt anything. And I imaging it might be able to grab a watt or two from the rotating mass of the motor as soon as the freewheel engages. I wouldn't call that true regen. its not recapturing the energy from the bike and rider.

Hello Drunkskunk, please refer to this thread http://www.endless-sphere.com/forums/viewtopic.php?f=3&t=9527. There is explanation about this. We donot want mislead anybody about it.Thanks.

 

[Drunkskunk]

I read that thread and have been following it.
For the sake of fairness, I have just read throiugh it again.
I still can't find any mention of how regen is possable with a freewheel. A motor must be engaged to the wheel to regenerate power from the vehicle, but must be disengaged to freewheel. it can only be one of those two states, so it either is a freewheel, or it can regen, but not both.

 

[louispower]

still wish to say a liitle more about the rege. by our kit it is not activated by the motor, but the controller at the moment of braking is applied. The controller will create a "reverse voltage" not only charge the battery but also brake the motor. During our test on a 48v motor, when brake lever is applied, it creats a reverse voltage reaching 58V for 2-3 seconds.That's all.

 

[Russell]

I'm still scratching my head about the "3-speed switch"!

2: Many of you are curious of the 3 speeds gear, actually this could increase the motor rpm by 10%-15%, at high speed gear. while ar low gear it limits the motor rpm although you use the throttle 100%, this means the current goes up, rpm lowered by about 20%, higher torque is available. I checked this with my enginner and he confirmed this is not realized by controlling the controller current;

could increase the motor rpm by 10%-15%, at high speed gear.

And how does it do this? Does it allow FULL voltage at this setting and throttle it at the "med" and "low" settings?

low gear it limits the motor rpm although you use the throttle 100%

Hey this I understand, the controller I got with my 9C kit has a low speed function...OMG it's a "2-Speed" model

So what does the "med" setting provide?

Hey how about motor performance curves for each setting of the switch :?

-R

 

[louispower]

look from the chart it is true, but with our kit when you apply "L" gear that means rpm will be lowered by 20% for higher torque.

OK a kit review will be soon available, let's wait for that.

Frankly you confuse the hell out of things with that "3-speed" switch...and BTW I still don't know what it really does :x

-R

Hi Rusell,

sorry but be a little patient of this please, when the review is available we could see if the 3 speeds gear works or not. thanks.

Thanks
Medium means no any extra force on rpm, it works as a standard bike :lol:

 

[Russell]

still wish to say a liitle more about the rege. by our kit it is not activated by the motor, but the controller at the moment of braking is applied. The controller will create a "reverse voltage" not only charge the battery but also brake the motor. During our test on a 48v motor, when brake lever is applied, it creats a reverse voltage reaching 58V for 2-3 seconds.That's all.

So not really regenerative braking as we know it but basically you're switching the motor into reverse while in motion??? But still if the motor is freewheeling it doesn't generate back EMF so the reverse voltage from the controller during braking would have to come from the battery so how can the controller be applying a reverse voltage AND be charging the battery at the same time?

-R

 

[louispower]

still wish to say a liitle more about the rege. by our kit it is not activated by the motor, but the controller at the moment of braking is applied. The controller will create a "reverse voltage" not only charge the battery but also brake the motor. During our test on a 48v motor, when brake lever is applied, it creats a reverse voltage reaching 58V for 2-3 seconds.That's all.

So not really regenerative braking as we know it but basically you're switching the motor into reverse while in motion??? But still if the motor is freewheeling it doesn't generate back EMF so the reverse voltage from the controller during braking would have to come from the battery so how can the controller be applying a reverse voltage AND be charging the battery at the same time?

-R

NO. The generation of reverse voltage depends on the bike speed, if over 15kph and brake is applied, there is reverse voltage,less than 15kph no reverse voltage. so how to think the reverse voltage comes from battery? Sorry I could not talk too much here about this, when the customer use this kit and think it's good, that's enough.

 

[Russell]

NO. The generation of reverse voltage depends on the bike speed, if over 15kph and brake is applied, there is reverse voltage,less than 15kph no reverse voltage. so how to think the reverse voltage comes from battery? Sorry I could not talk too much here about this, when the customer use this kit and think it's good, that's enough.

OK here's the thing I (we?) can't understand, if the motor is freewheeling it can produce no back voltage unless there is some type of clutch attached to the freewheel mechanism; is this true or not?

If the motor produces no back voltage then where does the energy come from to brake the motor electrically? If the energy comes from the battery then it's not regen is it?

-R

 

[Russell]

Sorry I could not talk too much here about this, when the customer use this kit and think it's good, that's enough.

No it isn't. If you come on a forum such as this you should expect questions about the features of your kit AND be able to explain them to your potential new customers.

-R

 

[louispower]

NO. The generation of reverse voltage depends on the bike speed, if over 15kph and brake is applied, there is reverse voltage,less than 15kph no reverse voltage. so how to think the reverse voltage comes from battery? Sorry I could not talk too much here about this, when the customer use this kit and think it's good, that's enough.

OK here's the thing I (we?) can't understand, if the motor is freewheeling it can produce no back voltage unless there is some type of clutch attached to the freewheel mechanism; is this true or not?

If the motor produces no back voltage then where does the energy come from to brake the motor electrically? If the energy comes from the battery then it's not regen is it?

-R

when someone try to hold a driving car it is difficult not to fell the car also wants to take him together :lol:

 

[John in CR]

We'll find out soon enough. I hope it's not just a brief instant of recovering some flywheel effect in the motor, because I need real regen braking, though any little bit is better than nothing. Assuming it's useful braking, then yes there has to be some kind of electrically activated clutch in there, in which case I completely understand the secrecy regarding details, though I see nothing wrong with saying that's what occurs. If it's just a bit of flywheel effect that very quickly stops due to the freewheel, then it's a marketing gimmick probably left best to ads, since it will quickly be discovered here and not really appreciated unless there's some support proving it recovers some meaningful energy.

John

 

[Drunkskunk]

still wish to say a liitle more about the rege. by our kit it is not activated by the motor, but the controller at the moment of braking is applied. The controller will create a "reverse voltage" not only charge the battery but also brake the motor. During our test on a 48v motor, when brake lever is applied, it creats a reverse voltage reaching 58V for 2-3 seconds.That's all.

So there is no actual regen of the momentum of the bike, just a recapture of the momentum of the spinning mass of the motor.

As with John, I won't be too happy if its just a marketing gimic, but lets hope there is more to it. Clutch? freewheel with a lockout?

 

[John in CR]

From Louis's post it seems to be some recapture of some flywheel energy, and getting something back is always better than nothing. The discussion has led to the need for an electro-magnetic toothed clutch inside a geared hub that results in engagement any time throttle or brake is applied. The unpowered state of this mechanism should be engaged, since the overwhelming majority of the time I think most would want engagement. Maybe even a switch to disengage would work. It might take some getting used to, or special throttle setups so coasting doesn't have immediate braking, but that's all doable. Even a mechanical lockout instead of electric could work, which if you want to pedal only or your battery is dead, you disengage the motor drag with some kind of mechanical switch. The way I ride, ie fast and lots of stop and go, the regen would way more than pay for itself, though I wouldn't want no way to freewheel. One consideration though is that these types of small geared hubs can't handle much current, so we could never get the kind of full on strong regen braking possible with a big direct drive hub, so I'll leave it to the inventors to come up with something ideal. 2 or 3 speeds in the mechanical gearing is also something possible, and should be on that invention list.

John

 

[louispower]

maybe a simple test couldl be done in this way:

you have a bike with the kit installed, but remove all the mechanical brakes. Use a voltage meter pre-connected with the battery, which could measure the battery output data, remember this data, say 51V.

Ride the bike downhills and acquire a speed, then use brake levers, at this time the motor is cut off with the battery. Since brake lever is applied but bike keep going at a speed because of inertia, while electronic brake is also applied. Overserve now the data the voltage meter shows, it will show a higher voltage than 51v, think where the extra energy comes from? It is impossible from battery itself.

It is best to use regulated power supply instead of the battery to make this test, as battery will absorb some extra energy then the result might be not very obvious. Under this case no need downhill anymore, just use throttle to let the motor rotate (surely without load), then use brake lever, obsering how much the voltage meter reads.

On our test on a 48v kit powered by regulated power supply, the result data reads 58v for several seconds.

Thanks.