Permanent Magnet Alternators (PMA)

[gastorgrab]

In the midst of yet another random search online (i was bored), another great idea popped into my head.

After hearing the complaints about the Home-brew Generators listed at this page, i thought of a method to solve the problem;


Build a generator from a lawn-edger motor.
http://theepicenter.com/tow02077.html

In 1996 we ran a Tip o' Da week submitted by David Hooper from Vancouver, BC, David.Hooper@INAC.inac-ainc.x400.gc.ca which discussed building a generator from an old lawn mower and a GM alternator. We recently received another set of comments from David on the subject and wanted to share them with you. We looked at David's idea and loved it! We think we have improved upon his idea though, presenting our version in addition to David's input!

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The solution:

Since an automotive alternator cannot charge a battery that dead, i wondered if there was a way to mount permanent magnets inside the alternator. Such an alternator wouldn't need to electrically energize a magnetic field to generate power.


Only someone beat me to the idea.......



Permanent Magnet Alternator Rotor Fits Delco 10SI / 12SI alternators
http://www.windbluepower.com/Permanent_ ... ma-rot.htm

Price $129.00

Have you got an old Delco 10SI or 12SI alternator lying around in the garage?? This Permanent Magnet Rotor will convert it to a PMA alternator for use as a wind generator or whatever else you want. This is the same rotor that we put in our "DC series" alternators and we realize not everyone has the money to buy one of our complete units but at this price you can afford to give alternative energy a try by building your own PMA from the parts you have lying around in your garage. You could also pick up a used Delco 10SI or 12SI from a salvage yard for under $25.00 and have a go at it.

Well if thats the case, those Gay 'Wind Generators' make a lot more sense!


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*Note - My own interpretation of a PMA would involve a handful of rare earth magnets, and a half-pint of epoxy. It probably wouldn't look as nice as the one above.
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[gastorgrab]

How the hell would you regulate something like that?

Whereas a standard automotive alternator uses a variable voltage at the 'Field' to limit overall output voltage, a 'Permanent Magnet Alternator' would be incapable of limiting itself. It's output would always be proportional to shaft speed.

That's a good way to explode a lead-acid battery!


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Does anyone know what method small engine aircraft use to generate power?

Certain motorcycles use a PMA-style alternators but their regulators are much too small to use as 'Homebrew Generator' stock.

The Wind-Power site (above) offers a regulator, but it's kinda small for this purpose. Besides being small (45 Amps max), i'm not sure if that PMA shaft would be compatible with a motor setup. I'm certain that the shaft speed of a small engine turns much faster that the shaft of a small wind turbine.




DC-540 Low Wind Permanent Magnet Alternator
http://www.windbluepower.com/Permanent_ ... dc-540.htm


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[träskmannen]

Gastor, I don't know if it has to do with my IP-address being non-US or if it is something else but the first link and the two first pics don't work for me. When I try to open the links directly in another tab I get an error message that I don't have permission to access them.

[gastorgrab]

I think that the website is having a problem.

I reloaded the page and and there is a 'Hot-Link' warning at the source (or what i though was the source).


---EDIT---


I think i have it now.

I had to trace the pic back to it's source, clear my browser history, and then save them to desktop.

The pics are now part of this thread.
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[träskmannen]

Thanks!

[gastorgrab]

Been watching 'Build your own Wind Generator' videos on YouTube.


While building his rig, a 'Free Power' enthusiast uses enough power tools to choke 20 whales, at the same time he's telling the camera "how good this will be for the environment".

Talk about tunnel vision.......


(Save the whale, save the spotted owl, save the oceans, save the baby seals.......... Kill the baby human! (abortion))


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I would imagine that it takes quite a large amount of power to create a permanent magnet of significant strength........but how much?

If magnets have that great of energy potential, and the magnets are 'man made', where is the break even point?



And were fossil fuels used to create that energy potential?


-----EDIT-----


It occurs to me that 'Saving the Planet!' would depend more on the efficient use of our energy resources rather than the type of resource used.
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[gastorgrab]

Ahhhhhh.........here we are!



Basic Tutorials: Charge Controllers
http://www.freesunpower.com/chargecontrollers.php

Why a Charge Controller is necessary



Since the brighter the sunlight, the more voltage the solar cells produce, the excessive voltage could damage the batteries. A charge controller is used to maintain the proper charging voltage on the batteries. As the input voltage from the solar array rises, the charge controller regulates the charge to the batteries preventing any over charging.

That's the final piece needed to build a generator that will start from zero volts.


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This has been a tutorial on how to use 'GREEN Power' technology in a really, really dirty way.


*Hint - for best results i recommend using a worn out Harley Davidson engine for the mechanical power source. This will both throw soot into the air AND ensure that none of your neighbors will have a moments peace.
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[Capmaster]

*Note - My own interpretation of a PMA would involve a handful of rare earth magnets, and a half-pint of epoxy.

Not epoxy. The TCE for epoxy is too different from the alternator materials and the magnets. Even if it held the first time you fired it up, and I have my doubts, once it cooled and warmed again it would become a mess internally when those magnets broke loose

[gastorgrab]

Would've been fun for a while.
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[gastorgrab]

What about a urethane based adhesive?

I was quite impressed with the Scotch-weld two-part adhesive that FoMoCo introduced me to.



My mistake! It was acrylic.

3M Scotch-Weld Structural Plastic Adhesive DP-8005
http://www.ellsworth.com/display/produc ... ab=Vendors

# Description:
# 3M™ Scotch-Weld™ DP-8005 is a two-part acrylic based adhesive that can bond many low surface energy plastics, including many grades of polypropylene, polyethylene, and TPO’s without special surface preparation. 35ml Duo-pak.

I had never seen a glue that would stick to nearly every surface. It didn't matter if it was oily-plastic.


---edit----


Scotch-Weld Adhesives
http://en.wikipedia.org/wiki/Scotch-Weld_Adhesives

According to 3m, Scotch-Weld is a "One system of adhesives and portable applicator combines many production benefits of hot melt adhesives and bond performance usually associated with 2-part structural adhesives."[1] Do-It-Yourselfers and Automotive enthusiasts value Scotch-Weld because it is one of the few adhesives capable of sealing and bonding Polypropylene and Polyethylene plastics. Most notable epoxies such as J-B Weld are not able to bond Polypropylene and Polyethylene plastics.

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[Capmaster]

Any kind of adhesive or epoxy would be asking for trouble. In a spinning, potentially high-shock environment like that you definitely need a mechanical retaining device for the magnets. Magnets are also typically rather heavy/dense. That makes securing it a real nightmare.

A non-ferrous bracket would be a better way to go Maybe a low-nickel stainless alloy like Martensitic ...or T6061 if it's thick enough.

[gastorgrab]

That's gonna kill my drill bits.
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[Capmaster]

That's gonna kill my drill bits.
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Go slow and use plenty of household oil as a cutting fluid. The mistake many make with harder metals is a too-high bit speed. GO S L O W !!

Stainless is probably one of the more difficult common materials to machine. Mild steel and brass are relatively easy. Copper, lead and pure aluminum are very tricky because of galling. On both the very hard and very soft ones you have to really keep the interface wet with oil or other cutting fluid.

My favorite materials to machine - brass and mild steel. My least favorites - tungsten and graphite

[gastorgrab]

Something you learn when 'metal working' is that; If your drill bit it squealing then it's not in continuous contact with the metal!

The noise you hear is the sound of the cutting edge skipping across the surface........... It's sounds like fingernails on a chalk board to me.


With Cobalt drills, you have to slow them down! You'll smoke them every time, otherwise.

Use them properly and they'll last forever.


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Aluminum is a pain in the ass!

It sticks to your drill bit. It sticks to your tap.......

Some of the lubricants that work include;

Nickle Anti-seize - Its very difficult to keep this on the surface thats being cut.
Aluminum Tap Magic - Great Stuff! (the machine shop guys showed me this)




http://www.tapmagic.com/TMaluminum.htm

Tap Magic Aluminum is the cutting fluid of choice for any work on aluminum (and other soft metals). Unlike some other fluids on soft metals, it will not stain the surface of the work. Precision is always excellent and the finish is always superb

All cuts on aluminum, magnesium and other soft metals. Drilling, tapping milling - you name it!

They carry this stuff at Amazon.com.
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[Capmaster]

I was preaching to the choir then. Sounds like you've done your homework

We used to use this milky-white cutting fluid on the lathes using the fluid pump/recycler. It looked like skim milk

[gastorgrab]

We used to use this milky-white cutting fluid on the lathes using the fluid pump/recycler.

I always thought the white stuff was strange. It looked like a water & oil mixture. It seemed to work good though.

If i recall, "the white stuff" acts as both coolant and lubricant.


Could it be exploiting the reluctance of 'organic' and 'inorganic' to mix? I have observed how well drops of water seem to glide over an oily surface. A surfactant added to the mix might adhere a thin layer of oil to the part being machined........like the way that soap works.

I'm no chemist though.
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[Capmaster]

Could be. I always thought it strange since I was a kid that adding oil, a lubricant, to a part being machined, made the cutter actually work better

[gastorgrab]

This is stupid!



440 AMP CONTROLLER
http://www.hydrogenappliances.com/batteryregulator.html

Used to prevent battery over charging on / Wind - Solar - Hydro
A battery regulator diverts excess power to power some other useful device when ever your battery is full.
Use this excess power to make free hot water or to recharge an auxiliary battery bank, so many uses, just to many to mention!

After reading about how standard automotive alternators "waste electricity by being electrically fielded", the PMA-style regulator (output regulator) strategy is willing to "dump" the excess power.


----EDIT----


Maybe a way to vary the stator coils would give better control.
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[träskmannen]

Aluminum is a pain in the ass!

It sticks to your drill bit. It sticks to your tap.......

The cheapest / easiest way is to use liquor to cool the drill bit (or cutter if that's what you're doing). Tapping is of course something else.

[gastorgrab]

Blasphemer!
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[träskmannen]

I wasn't talking about using say a 15 year old single malt from Oban (although that might be good for internal use once in a while for recreational purposes), I was referring to industrial grade ethanol.

I worked a short while at Bofors many years ago. We used ethanol in a spray bottle to cool the drill / mill when cutting in aluminium.

[gastorgrab]

From my re-print of a 1925 booklet entitled 'Handbook For Drillers';


For hard and refractory steel -- turpentine, kerosene, soda-water
For soft steel and wrought iron -- lard oil, soda-water
For malleable iron -- soda-water
For brass -- a flood of paraffine oil, if any
For aluminum and soft alloys -- kerosene, soda water
For cast iron -- should be worked dry or with a jet of compressed air for a cooling medium
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[Capmaster]

Tapping is of course something else.

Why? It's a cutting operation.

[träskmannen]

Turpentine does in many ways have similar properties to ethanol.

[gastorgrab]

What about a finely aged turpentine?
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[träskmannen]

Double-casked?


( )

[gastorgrab]

Is it just me or is the power coming out of the PMA's being handled in a very crude way?


In many ways the automotive alternator is much like a portion of power supplies we use every day (in our PC's). Why shouldn't the variable output be 'conditioned'? Depending on wind speed for for the GREEN jihadist, or shaft speed depending on the gasoline powered generator, the voltage level coming out of the modified alternator would not be constant.


Typical automotive alternator

cct.jpg (70.94 KB) Viewed 812 times

Example of a simple 12v power supply




Notice the capacitors?



Reservoir capacitor
http://en.wikipedia.org/wiki/Reservoir_capacitor

A reservoir capacitor is a capacitor that is used to smooth the pulsating DC from an AC rectifier.




Performance with low impedance source



The above diagram shows reservoir performance from a near zero impedance source, such as a mains supply. As the rectifier voltage increases, it charges the capacitor and also supplies current to the load. At the end of the quarter cycle, the capacitor is charged to its peak value Vm of the rectifier voltage. Following this, the rectifier voltage starts to decrease as it enters the next quarter cycle. This initiates the discharge of the capacitor through the load.

But where do you find big honkin' capacitors?
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[gastorgrab]

Bat Cap Model 300
http://batcap.net/Products/BatCap300/ta ... fault.aspx

The BATCAP Model 300 is designed for those enthusiasts who are looking for a performer. This model is known for it's ability to out perform even under the toughest conditions.

Weighing in at a mere 2.5 lbs., and able to provide an impressive 300 peak amps for 5 sec, the Model 300 will easily handle plenty of power.

The dimensions for the Model 300 are H - 2.72"/ W - 2.88"/ D - 4.23", making installation a breeze in tight places.

The suggested retail is $169.00.

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[Capmaster]

In a car the battery acts as a huge capacitor. No need for separate filter caps.

[träskmannen]

What do you mean with "a very crude way"?

There is usually some kind of voltage regulator limiting the maximum voltage and as Cap said there is of course usually a battery assuring a minimum voltage.