Ceiling fan bicycle generator

Hello, fellow metalworkers!

To prepare Surplus Center's 10-1134 ceiling fan motor for use as a bicycle generator to power abandoned buildings to 80 watts or so ( a few night lights and clock radios), I started by drilling six spot welds and removing the mounting brackets and spot weld kernels.

Then I sent the 17 mm shaft to Jensen and Tracy there turned it to 5/8 inch and slotted it to fit the cogs he thinned earlier. The eight tooth cogs are 2mm thick for bicycle chain now, and came with an integral key from Northern Hydraulic. They are go cart drive pinions.

5/8 key rings serve as spacers and a length of 1/4 rod or a loooong carriage bolt retains the cog. Internal nylon bushings in the 1/2 inch reamed 12 mm bore center the 1/4 part.

For my bicycle I used a Bike Nashbar adjustable stem set at + 15 degrees mounted to the front derailer mounting post, but then your bicycle probably isn't a Lightning Cycle Dynamics Thunderbolt, their base model. I milled the as-cast parts of the handlebar clamp to a 120 degree V to capture the motor with a long hose clamp. This has worked for hundreds of miles.

With the cog in place, I will need to experiment with 20 and 10 degree settings to get proper chain tension.

I've had it running for a few miles without proper chain tension but you don't want it falling off in the middle of a ride. You might have to pick up the pieces and that might make you late for your volunteer job at the library, or something. ;)

So I need to buy a length of spliceable old style chain. This is rather hard to find.

Anyway, to make it go, I put the cap in the brown lead as directed for CCW rotation seen from the shaft end on the left side of the bike, where the tandem stoker's crank is, and I pole it with 12 VDC for a second or so, then I fire it up, right? That's all there is to it?

So as long as I pedal I'll have variable speed and frequency AC in range for powering small devices. Right?

And as long as my load shuts down at 80 VAC it won't depole the rotor as the genny comes to a stop, right? But an incandescent load would depole the rotor.

I have doubts and want to get this right so I am asking for confirmation.

Surpluscenter.com not responding. Sorry. Nice motor for this app. Can you find one somwhere with a 5/8 shaft? Surplus Center has corrected the listing to read

17 mm, I believe. Perhaps you will find # 10-1134 when you visit.

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Yours,

Doug Goncz ( ftp://users.aol.com/DGoncz/ ) Student member SAE for one year. Loves in my life: Dona, Jeff, Kim, Mom, Neelix, Tasha, and Teri, alphabetically. So that is who I spend my time with.

Reply to
Doug Goncz
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Chain tension is best supplied by a spring loaded idler. On a bike the rear deraileur does this.

All modern chains are "spliceable". I just took a like out the other day 'cause it was bent. It took ten minutes. Buy a "chain tool" for $6-10. It is used to drive the pins in and out of the links of the chain.

You can do it without a chain tool using a punch, but its a real PITA.

-Greg

Reply to
Greg

I find the SRAM chains to be difficult to splice.

I always have a chain tool.

Yours,

Doug Goncz ( ftp://users.aol.com/DGoncz/ ) Student member SAE for one year. Loves in my life: Dona, Jeff, Kim, Mom, Neelix, Tasha, and Teri, alphabetically. So that is who I spend my time with.

24-35-51 / 34-28-23-19-16-13-11 = 6.57/11
Reply to
Doug Goncz

Well, I attempted to pole the rotor, first with 6 V, then 12 V, then 110 VAC half wave. After 110 VAC half wave poling, the output was a measly 0.4 VAC.

Something's wrong.

Yours,

Doug Goncz ( ftp://users.aol.com/DGoncz/ ) Student member SAE for one year. Loves in my life: Dona, Jeff, Kim, Mom, Neelix, Tasha, and Teri, alphabetically. So that is who I spend my time with.

24-35-51 / 34-28-23-19-16-13-11 = 6.57/11
Reply to
Doug Goncz

I don't think that'll work, Doug. It's true that an induction motor run above synchronous speed can produce rather than consume power, but it still needs AC excitation. At exactly synchronous speed the motor would neither consume nor produce power, but it would still draw excitation current from an AC line. This isn't power because the voltage and current are in quadrature in that situation. Below synch speed some component of the current is in phase with the excitation so it's a motor (load). Above synch speed some component of the current is out of phase with the excitation voltage so it's a generator (source).

The >Anyway, to make it go, I put the cap in the brown lead as directed for CCW

Reply to
Don Foreman

I'd expect a PM brushless motor would work pretty well as a

3 phase generator.

Doug - I think I may have Bodine 3409 stashed here somewhere that was pulled because it had one bad phase. You're welcome to it for the cost of shipping if you're interested in playing with it, and assuming I can locate it. The voltage constant is 47 volts/1000 RPM, the torque constant is 57 oz-in/amp. I don't recall if the bad winding was shorted or open.

Ned Simmons

Reply to
Ned Simmons

In

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the first hit we read:

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"By adding capacitors in parallel with the motor power leads, and driving it a little above the nameplate RPM, (1725 RPM ones need to turn at approximately

1875 RPM, and 3450 RPM ones at 3700 RPM) the motor will generate AC voltage! "

Now, my motor already uses a cap with the high resistance coil to produce a rotating field. Does this mean it's not an induction motor and can't generate?

Or is the combination of cap and coil inductance resonant and I just need to mount it on the bike, attach the chain and a pace meter, compute the gear ratio and positive slip speed, then crank at the right pace on the pace meter, _then_ look for output?

I'd been turning the motor by hand...

I have a drill press but it will only go to 550 rpm. I am planning to buy a slower speed drill press from Harbor Freight, one rated to lower speeds. But this is part of a thousand dollar repeat of the self-reproducing milling machine I made, at larger scale.

The college physics lab has a speed calibrated rotator drivable with adjustable power, not at a given speed, but with that limitation, I believe I can get 225 rpm +- 10% for experiments with positive and negative slip.

I used the rotator and my PM DC motor generator connected to 10 D size NiCd cells to draw a graph of speed versus power current in and out of the battery last year. I computed a power/mph slope and did a paper in Mathcad.

Yes, they do. Sanyo is having development with their 250 W three phase motor/controller combo. The hub motor is final, but they will not sell it without the controller which is still in development. So I pester Mr. Nakamura for a motor without controller and he says he'll "get around to it" meaning no hub motor yet.

That would really simplify the project.

It's an internally geared three phase brushless, sensorless hub motor ideal for use as a generator.

Sure, Ned, I'm interested. Is this motor still in production or available surplus? That's crucial.

What's the shaft size, what's the frame, and what's it weigh?

You can email me your payment address and the freight.

Rabbittool.com advertises the Sanyo hub motor but has nothing to sell.

Yours,

Doug Goncz ( ftp://users.aol.com/DGoncz/ ) Student member SAE for one year. I love: Dona, Jeff, Kim, Mom, Neelix, Tasha, and Teri, alphabetically. I drive: A double-step Thunderbolt with 657% range.

Reply to
Doug Goncz

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I'll look later today and see exactly what's wrong with it. All I remember is that it was being used as a servo in a positioning system I built and failed after several months, but I don't recall the symptoms. I'll let you know.

Ned

Reply to
Ned Simmons

Interesting!

I think the generators described on the website work by resonating the main winding with capacitance. Residual magnetism starts "pumping" this parallel-resonant circuit to get the excitation current required. Each revolution gives the resonant circuit another nudge, like synchronous pushes to a pendulum. Voltage would increase without limit until something limits it -- probably magnetic saturation in the iron.

Cool!

A fan motor may not work as well as some other induction motors because some fan motors sometimes have pretty high resistance. If it's "impedance protected" so it won't burn out when stalled, it may not work well as a generator because that winding resistance may spoil the Q of the resonant circuit. The 10-1134 motor is such a motor.

It sounds like your motor is a two-phase motor, the second phase being produced with a capacitor. That's quite common on fans because they run quietly. It's still an induction motor. I'd suggest that you ignore the high-resistance winding, just put the cap in parallel with the main winding.

I'd suspect (and the website confirms) that this setup will not start generating under load. You must rev it up and get the excitation established before you connect a load. You may need to experiment with caps to get the amount of capacitance that resonates with your motor. . Rev up the motor and vary capacitance while observing output voltage, going for maximum.

Getting the speed right may be important. You need the speed to stay fairly constant to stay near resonance. If the motor's nominal speed is 225 RPM, it's "synchronous" speed will be higher. The difference between synch speed and run speed is "slip" speed. To generate, you'll want to run at synch + slip rather than synch - slip.

Reply to
Don Foreman

Yikes, I haven't seen that website for years.. it's kinda cool that the info is kept available. I haven't looked up the motor you're using, but it sounds like it's a

2-phase motor, as Don suggested. The motors in the article are straight induction motors, and maybe split-phase motors (although it's a little odd that this wouldn't have been mentioned), since he stated his generator was a 1 HP pump motor.

All that said, I believe you want to try using a standard induction motor for your tests of this principle. I'd suggest using an AC powered 1/4" drill motor to drive your generator, and use a belt & pulleys to increase the speed for the generator.

WB ..........

approximately

Reply to
Wild Bill

Dear Don,

I'd theorized this also.

Yep.

Since there are many poles, each 3600/225 = 1/32 revolution plus or minus factor of two, that is it's got to be either 1/16 to 1/64 revolution pumps the circuit.

I'll bet they have arranged that.

Over 100 ohms minor coil, around 35 ohms main coil IIRC. I can have it rewound with silver magnet wire after I get it online..... The external coil _should_ have lower resistance than the equivalent internal (rotor) coil configuration.

I will recheck the namepate label, which gives the wiring configuration, for "impedance protected". The web listing does not say.

A fan motor or an impedance protected motor?

Yes.

Oh, thank God. Buy you a latte someday?

Eureka! Of course. Good thing I bought two caps.

Yes, shutdown under load will depole the rotor. However, my white LED signal light from Dialight, donated by John Viselli when I provided the serial number of the green traffic light I purchased on ebay under suspicious conditions, shuts down at 80 VAC. It goes off line automatically. The perfect match.

Or the driving speed.

Easier to affix the motor to the bicycle and crank at various speeds with known capacitance. Looks like it's time to buy a cheap LCR meter, or get out the scope.

Yes. I can drive the system backwards from the DC motor generator through the derailer and chain under light loads. The ineria of the wheel will stablize the speed. Dr. Majewski will provide 0-30 VDC for the DC motor generator.

But 3600/16 = 225. So this must be nominal.

Yes, I understand this and will look in my EET 350 text for more.

You've given me enough information to get out of this funk and get on with it. I'll report soon.

Thanks, Don.

Yours,

Doug Goncz ( ftp://users.aol.com/DGoncz/ ) Student member SAE for one year. I love: Dona, Jeff, Kim, Mom, Neelix, Tasha, and Teri, alphabetically. I drive: A double-step Thunderbolt with 657% range.

Reply to
Doug Goncz

Yes, I do but nothing else will fit up between the cranks!

Good idea. My usual approach is to put a nut, bolt, and rubber stopper in the drill / driver, and engage a tubular part driven with the rubber section. I use this for graining aluminum tubing at 45 degree crosshatch frequently, and they come out looking nicely finished.

Yours,

Doug Goncz ( ftp://users.aol.com/DGoncz/ ) Student member SAE for one year. I love: Dona, Jeff, Kim, Mom, Neelix, Tasha, and Teri, alphabetically. I drive: A double-step Thunderbolt with 657% range.

Reply to
Doug Goncz

Dear Group,

I've sent Ned my shipping adress. The Bodine is compatible with my existing Ametek, but what a wonderful difference in quality!

Yours,

Doug Goncz ( ftp://users.aol.com/DGoncz/ ) Student member SAE for one year. I love: Dona, Jeff, Kim, Mom, Neelix, Tasha, and Teri, alphabetically. I drive: A double-step Thunderbolt with 657% range.

Reply to
Doug Goncz

They didn't have to. Equilibrium will be reached when I^R losses equal energy pumped into the cap each bump, or when the iron starts to saturate a little.

Yes it did! It's impedance protected. Copied from web page:

New G.E. ceiling fan motor. Impedance protected.

Both.

An induction motor can't run at zero slip speed. Maybe it has 15 pole pairs which would make synch speed 240RPM, or 14 polepairs which would be 257.15 RPM. I say pole pairs because remember that a "2 pole" induction motor runs at 3450 RPM: 3600 - 150 slip.

>
Reply to
Don Foreman

Yahoo!

I poled the rotor with 6 VDC at like a tenth amp on the battery charger, connected the main and then the secondary windings solo across one or two 5/330 run caps, and also both windings in parallel that way, and drove the rotor with my hand electric drill at various speeds.

Very interesting behavior.

In many cases, there was a certain speed for maximum voltage output, below and above which (loaded only with DMM voltmeter) there was reduced voltage.

Max voltage reached so far:

5.3 VAC!

Ugh.

Do I need to get out the scope?

I'll count poles soonest.

Fabbed two mount halves today from 1/2 x 3 Aspen glued in four layers under six fire bricks as clamping to 2 x 3 dressed. Took the 5 1/2 inch hole saw, padded the work with paper, and sawed down two layers, snapped the waste, then finished to scrape the paper leaving a fine concave feature.

Set it all up on the self-reproducing HF drill press mill using the 4x6 pattern of M6x1 holes to take 4 SHCS as stops, and clamped. Nice finish.

A little self-adhesive sandpaper on the motor shell, some epoxy, and some dowels and screws, and it'll be rock solid. I'm facing the two cut blocks with maple to distribute the stress and installing T-nuts to take screw from the stem. I'm reinforcing the epoxy with wood screws from the inside. I'm reinforcing the solid mounting to the stem with a hose clamp. The hose clamp was all I had at first and it wasn't solid enough to let me load the chain the right way.

I set up the LED light today and a 3x3 foot sheet of paper in the kitchen. Drew out the triangular beam pattern. God, it's gorgeous. I can add a wooden block to mount the Dialight LED signal light (not a traffic light, it's white and 8 inch diameter) dead level later. Thanks to John Viselli at Dialight for the donation. This is really high tech. EIGHT WATTS!

Now, how do I get from 5.3 VAC to 110 VAC 60 Hz so I can run the LED signal light? (This is the whole point....)

Thanks to all. Let's keep at it, this could work.

Yours,

Doug Goncz ( ftp://users.aol.com/DGoncz/ ) Student member SAE for one year. I love: Dona, Jeff, Kim, Mom, Neelix, Tasha, and Teri, alphabetically. I drive: A double-step Thunderbolt with 657% range.

Reply to
Doug Goncz

This is what is wrong. The web page recommends 150-200 mfd run caps or back to back electrolytics. AC power flows through a run cap. AC just flows in and out of the generator caps. I think using a run cap for the genny is overkill. My run cap is 5 mfd and it's the size of my fist.

So I think I'll get out the scope, wire up each coil and the combinations in parallel and series, and hit them with the deflection from the scope, and draw the circuits up, with each labeled with the resonant frequency. Then (I could do this with one measurement, but I'm playing) I can calculate the inductance of the coils, and knowing their resistance, compute the cap size to resonate at

60 Hz.

Sure am glad I still have the scope. If I didn't I'd have to use Daqarta. Of course, Daqarta gives a more precise frequency, but I don't need 0.001 Hz resolution for a ten pound AC generator.

My DMM's frequency function may be blown. If so, I'll go with Daqarta and really learn something.

As a generator, having the coils in parallel produces the lowest source resistance. So maybe I'll leave the run cap in permanently, and put the other across the terminals, find one resonance, and adjust.

I don't know but at least it's mounted solidly now. I glued up the blocks, epoxied them to the motor with six 10-24 x 2 inch screws, square nuts, and an acrylic washer plate, then drilled the plate and wood for four #8 phillips head sheet metal screws. I screwed the stem to the block (are my arms ever tired), then added a hose clamp for reinforcement and set the stem all the way up to give the minimum lever arm when I hit a pothole.

Solid like a gravestone. I think.. We'll see Saturday or maybe tomorrow.

I worked two hours for free at the library. If you'd care to visit, you'll find two bookcases in good order. From Win 98 through XHTML to Access and PowerPoint.

Yours,

Doug Goncz ( ftp://users.aol.com/DGoncz/ ) Student member SAE for one year. I love: Dona, Jeff, Kim, Mom, Neelix, Tasha, and Teri, alphabetically. I drive: A double-step Thunderbolt with 657% range.

Reply to
Doug Goncz

I suspect the capacitor size will be prohibitively large to resonate at 60 Hz. You might do a quick calculation with some estimated inductor sizes to get an idea of the order of magnitude....

- Bob Headrick

Reply to
Bob Headrick

I would spend a little more time making sure that this motor is actually suitable for use as an induction generator. Ceiling fan motors are notoriously inefficient, as a quick www search will reveal. They have thin wire (high voltage drops) and large gap leakages compared with motors which do real work. The ceiling fan motor market is very price sensitive. It sounds like resistance is not an issue yet, since you are only loading with a DMM. This is essentially no load.

It is really tempting to use a ceiling fan motor, since they are cheap, mass-produced, and operate at low RPM's. But it might be wise to spend more time finding out if you can get decent output from this thing, under load, so that your fancy mount won't be thrown in the trash (needless waste of resources and time). Test it under the designed load!!!!!!!!! Typical fan motors are about 60 watts. Light bulbs of this size are readily available and occasionally may be scrounged for free. Try to light one of these bulbs to full brightness.

Reply to
Eric Chang

Bob's right, it doesn't have to resonate.

I went to bed at 9:30 and got up at midnight. Had a smoke and a cup of coffee and went over to the shop.

Installed the rotor and pinion, a new chain ring, length of spliced chain, and ghost cog for tensioning.

Ran the rear wheel off the motor in high gear.

Video and a jpg at:

ftp://users.aol.com/DGoncz/Bicycle/ACMotorGenerator

Yes, it got warm, yes, it's not an efficient motor, but the load is only 8 watts.

I'll put 150 mfd of run caps across the main coil and see what happens with my white LED light as load.

You know my dad, Joseph Paul Goncz, was always delighted to receive JPG files. He took it personally. What fun he had.

Yours,

Doug Goncz ( ftp://users.aol.com/DGoncz/ ) Student member SAE for one year. I love: Dona, Jeff, Kim, Mom, Neelix, Tasha, and Teri, alphabetically. I drive: A double-step Thunderbolt with 657% range.

Reply to
Doug Goncz

Err, why bother? Okay, I probably know why.

What I would like to point out to you is that some of the aid agencies/technology aid mobs have web pages on wind generators that can be built in the boon docks. They might be a lot less work for greater return.

Reply to
Terry Collins

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