Alternator Motor - Thee itch I need to scratch

That would be one really hard to ride bike, unless it was downhill on a steep slope, if that alternator is being used to charge the battery rather than as a motor.

I used to use those little tire-driven generators with incandescent lights for my head and taillight, and they probably werent' even 20W drag on the wheel, and wore me out pretty quick in higher gears. With a single-speed like his, and all the big and little hills to climb in most places in Japan, I can imagine it could suck pretty bad sometimes (would have to either walk the bike up the hill, or disengage the alternator from the wheel).

I strongly suspect it is being used as a motor, but I am not sure how he's running it; I didn't see a multiphase controller on there, which would be needed to spin it even if it's a PM type or has been converted to such.
 
Hillhater said:
boy, ! that steering wheel is neat though ! :D and the gear shift on the fork stem !! :shock:
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The man is totally out of his box, which is brave for a Japanese.

he said something about an airbag??

:lol: j/k

Oh, no way the alternator would be able to drive the tire, not enough traction on the metal pulley! It's gotta be a generator...
 
The actual translation for the title of that "Brasilian" man is:

Steering wheel bicycle with an alternator.

I used to see a few bicycles with a similar set up, but powering car audio system and this was in the 80's lol.
 
:? hold up one tooth-pickin-chicken minute...

An alternator & voltage regulator, when used in a car, feeds its own power to its own rotor coil immediately after the battery/starter turns the alternator/engine, does it not? The battery is used to store excess power for later use of the starter and electrical accessories.

Can the battery be bypassed? When slowing down in regen mode, is it possible to use just a quick excitation from the capacitor for the alternator to generate minimal volts, and in turn, could that power be fed back to excite the coil to generate higher voltages to be fed to the capacitor?
The capacitor will be used like a battery, the difference being, the cap powers the rotor coil for dead stop take off, instead of turning the alternator/engine like the battery does.

Is this power feedback feasible? If not, I'll have to use a separate battery pack to excite the coil for torque on demand...
 
alan c said:
Hi Im really keen to give this a go . Dose anyone know if you could use an e bike sensorless controller instead of an rc one cheers :shock:
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:D
 
Hi I dont think so. I could be wrong but i think the battery powers the field and the regulator regulates how many volts go in.If you by pass the regulato 8) r and run 12v direct to field you get the same amps but the faster you spin it the more volts .I have seen 250+ Cheers
 
alan c said:
Hi I dont think so. I could be wrong but i think the battery powers the field and the regulator regulates how many volts go in.If you by pass the regulato 8) r and run 12v direct to field you get the same amps but the faster you spin it the more volts .I have seen 250+ Cheers
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:x This regen/capacitor puzzle is making me cat sh!t crazy…. I can't wait to buy an alternador to test my theories. Cheers for your input. I look forward to seeing you kick off your project!
 
Hey guys,

Around this time last year i built an Alternator driven mountainbike using a Hyundai Excell 40A alternator, a 100A BLDC ESC, a 10amp Brushed speed controller for field current control and cast my own brackets, pulleys, friction drive roller etc. I built a small Controller that connected to a variable resistor style throttle control (from oatley electronics) and feeds both the ESC's as well as an LCD to show Motor RPM, Rotor and Field Pulse Width. The controller used a lookup table to control the Rotor current depending on Rotor Speed and Throttle %. It was friction drive and i 'tuned' the controller for peak torque at varying speeds by adjusting the rotor current at a given rpm at max load (Holding the brakes on). I've since been sent overseas with work and never had the chance to take it for a ride. Im back in Australia now and the removalists will be delivering all my stuff next week so ill be able to finally test it.

If anyone is interested i can post what photo's i have, the rough measurements, schematics, source code for the micro etc. Also, the boards i've designed for the controller had a minimum order of 10pcs from the PCB manufacturer, so i have a few spare if people are interested. Likewise, i can reproduce the castings if they are wanted.

-Ben
 
Hi Dee Jay,

Here's a photo of the Alternator and the first bracket i casted. It fits in that little triangle under the seat, there should be a backing plate behind it to secure it to the bike with some inner tube rubber to keep things nice and snug.
15112010183.jpg

Here is how it sits, unsupported.
15112010182.jpg

Rear view of friction drive assembly, assembled
13122010187.jpg

Left hand view
13122010184.jpg

Right hand view
13122010185.jpg

Here you can see the prototype controller with LCD, Both ESC's , Belt tensioner, the polystyrene textured bracket (from the lost foam method of casting)

I used rollerblade/skate bearings in the friction roller, i figure they should last a while, they're designed for this kind of loading and they come in packs of 8 so plenty of spares if/when they do fail.
Also, i cant remember the max speed of the alternator but i fried an esc after it lost sync. At the time i noted it down and put a rev limiter in the software of the controller.
The motor was reconfigured into delta for more power and higher rpm. (It was actually from a mitsubishi mirage, not an excell...)

There's heaps more that went into the design of this thing, any questions feel free to ask
 
Dee Jay said:
:? hold up one tooth-pickin-chicken minute...

An alternator & voltage regulator, when used in a car, feeds its own power to its own rotor coil immediately after the battery/starter turns the alternator/engine, does it not? The battery is used to store excess power for later use of the starter and electrical accessories.

Can the battery be bypassed? When slowing down in regen mode, is it possible to use just a quick excitation from the capacitor for the alternator to generate minimal volts, and in turn, could that power be fed back to excite the coil to generate higher voltages to be fed to the capacitor?
The capacitor will be used like a battery, the difference being, the cap powers the rotor coil for dead stop take off, instead of turning the alternator/engine like the battery does.

Is this power feedback feasible? If not, I'll have to use a separate battery pack to excite the coil for torque on demand...
Click to expand...

Its entirely possible and quite easy to implement a Regen system, especially with an intelligent controller in charge or rotor current. Add a brake switch to the controller to regulate rotor current to generate a suitable charge voltage/current for the battery pack, not to mention avoiding locking the rear wheel up. As for using a audio cap for field current... You could, it wouldnt last long pulling an amp or two, a few seconds at best i'd say. Good enough for a take off i suppose. You'll be burning 10's of amps with an alternator under a reasonable load, whats another few hundred milliamps for field current???
 
Thanks for the input and the effort of posting your build, Ben!

Oh so you have 3 controllers..seems more complicated than what I had in mind. Anyway, lots to consider and lots to get my head around with your approach.

It's good to see others exploring an alternative motor *rimshot* :lol: No apologies for my puns, 8) sorry... :x doh!

:lol:
 
Salty9,

For testing and the setup of the controller i used a 24v Lab powersupply capable of 60Amps before the overcurrent limit kicks in. From memory, no load (wheel of the ground) current draw was from 4amps(ilde) to around 16Amps at a wheel speed of 75km/hr. This setup could easily draw more than my powersupply could deliver tripping the overcurrent when loading the back wheel at high speeds. I put the high idle currents down to the cooling fans internal to the alternator as a fair bit of air is pushed from them, as well as the pulleys and belts and ofcourse the friction drive itself. So 24v @ 60Amps = 1440Watts, and that was only at partial throttle. My plan is to use a 48v setup as its more suited to an alternator spinning at 5000rpm (which is around the 60km/hr mark)

-Ben
 
lutach said:
The actual translation for the title of that "Brasilian" man is:

Steering wheel bicycle with an alternator.
Click to expand...

:lol: Oh, I get it.. he's just calling his creation a Car Bike (Bicicleta Volante) because it has car parts

:?
 
You guys are not the only ones to be messing with Altermotors.

I have 3 alternators, one 25A, one 100 A, and one 200A and a bunch of hall sensors. Just got a decent Dremel to hog out places for the halls. Have a 36 V 100A PWM Controller from another source. Absolutely do not know anything about Electronics, so, I will be watching and hopefully learning how to make one work.

Please post everything you guys do, good OR bad, so maybe I can get a grasp of what is really needed to do this.
 
Harold in CR said:
You guys are not the only ones to be messing with Altermotors.
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Alright! Another altermotorist! 8)

*ding ding ding*

I'm going to use a front wheel generator hub to charge the capacitor!

I've seen some of the generic ones standard on some generic bikes and they produce very good luminescence (?) so that should be enough to charge the cap.
huh12.jpg
And I assume they're low drag since they are prebuilt in a wheel, unlike a lot of the generic friction driven generators which you have the option/need of physically disengaging when not needed, and those things are noisy.

:idea: Generator hub while cruising, and alternador regen when slowing to a stop. That's the ticket! 8)
icon_cool.gif
[youtube]jVGo8TLp40A[/youtube]
 
I found PM pill magnets at a dollar store that comes in a package of 4 pills. Strong puppies..n45, I think?
CIMG0088x.jpgCIMG0002x.jpg
I wasn't sure what I would need pill magnets for but I knew they will somehow be useful on my whacky projects.

Then I got to thinking ( you know how that goes...): large doughnut PM's are not cheap and getting the right size in Japan will take some research...what if I formed the pills into several rods to make a ring and fit them inside the rotor claws? CIMG0001x.jpg
claws.jpg
View attachment case.bmp
stay chooned!
 
On the R/C Forum, there is a lot of talk about the quality of steel used for laminations. Also, there are photos of permanent magnet rotors. I am scanning the internet, looking for a company that has "blank" circular lamination pieces. Making a rotor would not be a big deal, if I can just find the correct steel. Then, coat the pieces and bolt them together.

Have you noticed the thread about Speaker magnets ??

Have you checked out the R/C forum thread ?? It's very long, and, full of snipes against Randy, AKA Bob Diode, AKA Altermotor, AKA several other handles.

Still, there is info that will work to make these conversions. Here is a link. http://www.rcgroups.com/forums/showthread.php?t=905411&page=11. Really seems that the "Denso" brand of Alternator, is a very good candidate.
 
Cheers for the info, John!
Not sure if I would need the proper lamination since I will work with the rotor claws until I can afford the wind generator PM rotors.

I'll check out the Speaker magnet thread soon! Thanks 8)
 
I'm going to be going down this route as well (initially anyway) and hopefully converting a truck alternator (yet to be sourced) into a 3-phase PM motor.

I understand from following a few links here and elsewhere that some form of electronic gearing can be obtained using an alternator in it's natural form (something about the rotor having power applied to it as well - I won't pretend to understand how this works) but the way I see it if the rotor is replaced with a PM rotor and the wiring and connection scheme in the stator is improved, the motor should overall be much more powerful, and negate any advantages that could be had from the electronic gearing.

I also figure that if I can find a alternator that is common enough, a few motors could be built, daisy chained together and a rather powerful motor could be the end result (for say...a car).

I'll post any progress in these forums, but if anyone else does/has done anything with these sorts of motors I’d be super keen to hear from you.

Cheers.

- Matt
 
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