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Author Topic: Dia. Mag. Alternator  (Read 190196 times)

DreamThinkBuild

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Re: Dia. Mag. Alternator
« Reply #240 on: July 30, 2011, 12:55:01 AM »
Excellent work Z.Monkey,

That looks to be a pure labor of love, in the mechanical sense. :)

z.monkey

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Re: Dia. Mag. Alternator
« Reply #241 on: July 30, 2011, 01:38:38 AM »
Thanks DTB,
Electromechanical, LOL!

z.monkey

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Re: Dia. Mag. Alternator
« Reply #242 on: August 02, 2011, 12:32:57 PM »
Got the inside of the stator cleaned up and wired the coils to a terminal block.
The coils are wired in series.  Driven with the battery power drill at 1400 RPM,
it produced about 5 Volts open circuit.  Then driven with the Dremmel tool at
30,000 RPM produced about 22 Volts open circuit.  The rotor is slightly out of
balance, and produced considerable vibration at 30,000 RPM.  So, I need to
get the rotor balanced before I try that again...

The voltages are a little better than the DiaMag7, but I think the current is
going to be the real improvement.  There is a lot more pole area on the rotor
which should, in turn, produce more current.  Next task is to build an adequate
load...

z.monkey

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Re: Dia. Mag. Alternator
« Reply #243 on: August 18, 2011, 04:29:09 PM »
Dig and you shall receive...

I found this document about shaft and rotor balancing on the interwebz.
It looks very thorough, covers static and dynamic balancing, and even
field balancing, as well as all the math involved.  Since I don't have a shaft
balancing machine I will have to use static balancing to balance the
DiaMag8 rotor.  Basically I need to build a non-magnetic  stand to hold the
ends of the shaft.  The seats where the shaft rides have to be ultra low
friction so the heavy point of the rotor will fall to the bottom.  Then I
can remove a bit on material from the heavy side, and try the balance
again.  This process continues until there is no perceptible heavy spot
on the rotor...

Here is the download page...
http://www.overunity.com/index.php?action=downloads;sa=view;down=481

z.monkey

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Re: Dia. Mag. Alternator
« Reply #244 on: September 08, 2011, 03:00:17 PM »
http://scientilosopher.blogspot.com/2011/09/diamag8-test-platform.html

This is a repost.  Nutshelled, got the rotor balanced.  Drill is too slow,
Dremel is too fast.  in the process of building a variable speed alternator test platform...

z.monkey

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Re: Dia. Mag. Alternator
« Reply #245 on: September 10, 2011, 02:12:48 PM »
looking good z.monkey, soon the fun shall continue hopefully with no more aluminum shower ;)
Thanks Webby,
Would you like some fresh grated aluminum with your test?

Hope

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Re: Dia. Mag. Alternator
« Reply #246 on: September 10, 2011, 05:02:08 PM »
Your Mag Alternator is a work of art Z!   Nice job.

This is how the out come of the energetic forum bifilar coil works, it is finally working out and making production beyond the input.  You will see in an instant how to adapt the concept to your projects so I am including it here for all.



z.monkey

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Re: Dia. Mag. Alternator
« Reply #247 on: September 15, 2011, 01:54:34 AM »
Thanks Hope, I think I hooked up DiaMag6 that way.
http://www.overunity.com/index.php?topic=9220.msg264813#msg264813

Working on the platform now.  I'm making some tongue in groove right angle
brackets to hold the motor/alternator plate, and the platform base together.

http://scientilosopher.blogspot.com/2011/09/scrap-bar-clamps.html

z.monkey

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Re: Dia. Mag. Alternator
« Reply #248 on: September 19, 2011, 01:59:22 PM »
Been clearing space, deconstructing old stuff scavenging what I need to
build the new stuff.  Got the groove cut in the piece of 1.25 inch square
pine to be the meat of the right angle brackets.  Then made some triangles
with 3/8" plywood...
http://scientilosopher.blogspot.com/2011/09/groovy-brackets.html

z.monkey

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Re: Dia. Mag. Alternator
« Reply #249 on: October 02, 2011, 09:18:11 AM »
Building the pedestal for the test plate.  I mitered some
square pine stock for a frame.  Then glued and screwed
the pedestal base together.  Cleaned up the groovy
brackets, and glued them together.  Then test fit the
motor/alternator plate.  Looks good so far...

z.monkey

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Re: Dia. Mag. Alternator
« Reply #250 on: October 02, 2011, 11:13:06 AM »
Aqua-VI

z.monkey

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Re: Dia. Mag. Alternator
« Reply #251 on: October 03, 2011, 12:59:24 PM »
Mounting the motor plate here, and then adding the electric controls
for variable voltage and current...

energia9

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Re: Dia. Mag. Alternator
« Reply #252 on: October 03, 2011, 03:35:45 PM »
Aqua-VI

i love your work Z Monkey, you are doing continous work on your idea, this is what overunity people should all do... keep up the nice work my friend....
what are your future goals?

peace

z.monkey

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Re: Dia. Mag. Alternator
« Reply #253 on: October 22, 2011, 06:28:38 PM »
Thanks energia9,

I wish I had more time to devote to my projects.  Unfortunately I have many things to maintain, and over the past few weeks I have had to spend most of my time on my day job.  I am working towards making an actual product that I can sell, and turn that into a business.  Then maybe I can shed the day job.  This sounds simple enough, but it is a little harder than you might think.  The day job parallels my projects, so this is good in that the experience I gain there benefits my projects, and in my spare time at work I can work on my projects.  Slow progress is still good progress...

So, the Test Platform is coming along good.  I built a speed control board for controlling the voltage to the motor which is driving the DiaMag8 Alternator.  I want to overdrive the motor, so I built a 24 volt battery pack.  Then I can adjust the voltage going to the motor with the speed control board.  The motor is rated at 12 volts and I am wanting to take it up to about 18 volts to hit my target speed, which is 3600 RPM.  The label RPM is 2350 at 12 volts.  The pulley ratio is 1 to 2.3, so when the motor is turning 3600 RPM, the Alternator will be turning at 8280 RPM.

My initial design for the speed control didn't quite do what I wanted, and I had to rework it.  Originally I wanted a voltage control and a current control.  But the voltage regulator wasn't providing enough current and the current control just didn't work.  So I reconfigured the voltage regulator to drive the current regulator directly, and now only have one control.  At least now it works, schematic below.

Then there are the battery issues.  Big Sigh!  I had the D Cell battery holders and a bunch of D size batteries that I have used for projects in the past.  These batteries have been in the shop for years, and been used for various other projects and in flashlights, and all of them are mixed, unknown state.  So I get the battery pack put together, go test it, flip the switch and watch the voltage take a dive.  Uulgh...

There are 16 D cell batteries in the battery pack.  i had a thought to go buy new batteries.  I did test all the batteries and weeded out a few dead ones, but even then the battery pack would just barely turn the motor.  At this point I was really frustrated, and just walked away from it.  The next day I found a 12 volt 7 Ah sealed lead acid battery that I could use for testing.  So, after reconfiguring the battery I finally got the motor turning.  I am driving the motor directly with the lead acid battery because the voltage is too low to use with the speed control board.  Ultimately I want to replace the D cell batteries with new ones, and then I can use my speed control.

On to the next problem.  At 12 volts the motor is spinning at 2350 RPM, time the pulley ratio of 2.3, is 5400 RPM.  The alternator develops about 18.5 volts AC, open circuit.  This part is good.  The bad part is at this speed the centrifugal force on the aluminum rotor is causing it to stretch, and it is crashing into the stator.  This is extremely frustrating.  I regret using a soft metal on the stator.  I didn't have this problem before with the solid Neodymium rotors, they are very hard, and don't stretch much when taken to extreme RPMs.  So, now I have to take apart the DiaMag8, again, and try to increase the clearances around the rotor without damaging the windings.  Without the windings this would be relatively easy, just a mater of filing down the stator.  But doing this with the windings in there is kind of precarious.  Worst case scenario if I damage the windings is I will have to unwind and rewind the stator.  So, hopefully I can be intrepid enough to increase the clearances without damaging the windings...

So, getting there, very slowly...

z.monkey

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Re: Dia. Mag. Alternator
« Reply #254 on: October 23, 2011, 01:15:46 AM »
Doh!

Found the problem...

I was all busy filing down the stator, and not making a difference.  I was looking at the rotor very carefully while it spun up.  I could see a definitive point where the rotor jumped up an hit the stator.  That's weird, why doesn't it expand gradually increase in diameter.  Why does it suddenly jump up like that.  Then I started inspecting the rotor.  The damn epoxy failed.  The magnet are loose, and when the centrifugal force exceeds the magnetic attraction the magnet pops out and hits the rotor, making a nasty grinding sound...

Forksocks!  This is exactly why I typically secure the magnets using hardware and not glue....

Aaargh!  Well, now I know.  The smooth surfaces of the metal make for a not so good bonding surface, and the epoxy was the 5 minute variety, so there is the very good chance the epoxy would fail.  Damnzit!  These radial segment have no other way to secure them.  No screw holes...

Looks like I'll have to use to industrial epoxy to get them to stick...

Well, at least I found the problem...

BTW, killed the Dremel Tool grinding the stator.  Yay!  Gotta buy another tool...