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Author Topic: Dia. Mag. Alternator  (Read 190185 times)

z.monkey

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Re: Dia. Mag. Alternator
« Reply #165 on: March 29, 2011, 01:42:23 PM »
JB Weld, takes me back to my hotrod days...

Well, unfortunately Ferromag fluid isn't gonna help this design.

The configuration of the coils relative to the magnets makes for a low efficiency design (like 5%, maybe).  I could also look at it as low drag, which is what I need for experimenting with the UABMM.  There are two axioms when working with induction; (1) the field only induces current in the wire when the field is moving, and (2) when the poles of the field are pointed at the wire.  Side currents are irrelevant.  So this design is more like a pulse generator than an alternator.

I probably read those axioms a hundred times, and still didn't get it until I was debugging my DiaMag6 design...

I tried to get a scope shot of the output.  My work area is very noisy, and I haven't been able to filter out the 60 Hz, so this shot is riding on a 60 Hz wave.  The first shot is just the 60 Hz.  Then the other shot is DiaMag6 running on the wave...

Also, moving forward, I need to get way more efficient, and easier to manufacture...

The 3 magnet design is out, going back to one magnet.

Gears are out, too expensive, too much drag, simply inefficient.

The hybrid design moderately worked, made a pulse generator, need more study there, with the UABMM...

DiaMag7 will be a single diametrically magnetized Neo-Mag, and polyphase coils instead of the side solenoids.

z.monkey

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Re: Dia. Mag. Alternator
« Reply #166 on: March 29, 2011, 04:39:48 PM »
Are you planning on using the mags in the UABMM for the field force?
The UABMM provides the rotation, the DiaMag6 converts the rotation into electrical current.

z.monkey

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Re: Dia. Mag. Alternator
« Reply #167 on: March 29, 2011, 05:06:49 PM »
The smallest circle in the middle is the axle.  The next circle out is the bearing.  The next circle out is the outside diameter of the magnet (1.5 inch diameter).  Then the slots hold the windings.  This is where DiaMag7 is different from the other DiaMag Alternators.  The windings will be on opposite sides of the magnet and not offset to the side.  Its 2 poles (one magnet), and what we would normally call a stator in an alternator is a solid Neo-Mag thick ring magnet in this case.

z.monkey

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Re: Dia. Mag. Alternator
« Reply #168 on: March 29, 2011, 05:56:53 PM »
We could spin the alternator with wind, or water, or a gas motor, or bicycle cranks, but I thought a magnet motor would be a lot more challenging and fun.  Mainly to see if I can get it to work, but also it may widen our alternatives in electric production.  I've got better tools now, so DiaMag7 will be easier to build than DiaMag6.  Building DiaMag6 was an abysmal process, it took months...

z.monkey

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Re: Dia. Mag. Alternator
« Reply #169 on: March 30, 2011, 12:41:12 PM »
So this is a pretty complex wave form...

It seems the current generation has some contention in there.  I think I know why.  The coils respond to the poles.  As the poles pass the coil there is pulse of current generated.  The magnets are synchronized with the gears (perhaps not very precisely), and there is a N pole and a P pole passing on opposite sides of the coil.  This would cause the current to be pulled quickly one direction, and then the other, causing a voltage spike positive, and then negative.  There are 2 vertical coil segments that are affected by the magnets, so we should get 4 pulses per revolution, two pulses per pole passing, and two poles passing.  Then also the other coil is tied to the center tap, so there are the compliment pulses on the opposite polarity, perhaps not quite synchronous.  So the output is a sloppy, almost square wave, with a lot of neutral time.

I can probably make this a lot less complex by removing the gears, and the outer magnets, and try and get another scope shot with only one magnet spinning...

That wave form makes me say WTF?

z.monkey

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Re: Dia. Mag. Alternator
« Reply #170 on: April 02, 2011, 02:28:08 PM »
I hit the Metal Shop early today.

I found a piece of 1/16" Aluminum which is just right for the DiaMag7 mounting plates.  I got it marked up first, then got busy spotting.  The piece was a little long, so I trimmed off the excess and also made a slot between the two plates to help separate them.

z.monkey

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Re: Dia. Mag. Alternator
« Reply #171 on: April 02, 2011, 02:40:25 PM »
Now that I have the piece roughed out, I can start getting it ready to assemble on the rotary table for the fabrication process.  First I need to mark the slots.  Also had to redraw a few lines that got smudged.  I use a carbide pencil to scratch lines into the Aluminum, and then a marker to color them.  Then I needed to finish off the holes.  The holes are matched to my fixturing clamps for now.  Then after this process we will take them out to the finish diameter.

I separated the two mounting plates with a sheet metal shear do that I wouldn't loose any material between them.  The shear bent the plates a little so I flattened them out again on the anvil, with the blacksmith hammer.  Also made a sacrificial block to ride underneath the mounting plates during the machine process.

Then both the mounting plate and the sacrificial block get mounted on the rotary table for the fabrication process.  The two plates are aligned, and locked in place, so in the end we will have two identical pieces, hopefully...
« Last Edit: April 03, 2011, 02:19:37 AM by z.monkey »

z.monkey

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Re: Dia. Mag. Alternator
« Reply #172 on: April 02, 2011, 09:46:18 PM »
Bet you thought you wouldn't see the Bitmore vise again...

The assembly was too high for the Palmgren Table, so I had to backpedal and use the Bitmore table.  Its not a bad table, just has some quirks.  I had to get some shorter metric (M5) screws to secure the mounting plates to the rotary table.  Also had to fit them, of course I couldn't find a screw that would fit right without modification.  After that I was ready to cut.

I started with the circular peripheral cut to isolate the mounting tabs.  Then cut the slots.  The slop in the two tables was troublesome, but by making slow cuts, and really clamping everything hard I got around it, somewhat.  I had a few SNAFUs, but I think I can work them out with the small files.  So, basically, the new mounting plates are rough cut, and we're on to the finishing process...

z.monkey

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Re: Dia. Mag. Alternator
« Reply #173 on: April 03, 2011, 12:26:20 PM »
These mounting plates are not purrfect, but I didn't breach the magnet space with the slot cuts.  So, hopefully the magnet will spin freely.  I'll apply OTF fixes (On The Fly) as needed to make it work.  I am cleaning up the mounting plates with tiny diamond files.  They are great for precision work, but are very fine, so making big cuts is time consuming.  Some of the clearances are not even close to what I want, but you know, we'll make due with whats we got...

Next step is to cut some aluminum tubes to be the stand offs between the plates.  I have some brass bolts for the supports inside the Aluminum tubes.  Then I need to fit the mechanical pieces together, and square them up to make sure there is adequate clearance for the spinning part (1 inch diameter Neo-Dia-Mag).  Then once the mechanicals are happy I can get to winding the polyphase coils...
« Last Edit: April 03, 2011, 12:56:45 PM by z.monkey »

z.monkey

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Re: Dia. Mag. Alternator
« Reply #174 on: April 04, 2011, 02:04:54 AM »
In case you have been having trouble visualizing the end product, here it is...

The 1/16" Aluminum is a lot more rigid than I thought it would be.  I didn't breach the magnet space, and now this is visually verified.  I have somewhere between 30 and 50 mils of clearance around the magnet.  The Aluminum spacers are a little short on purpose.  This puts a little tension on the plates so that there is no lash in the bearings.  The bearings are happy, and the shaft spins freely.  There is no motoring on the chassis because there are no ferrous elements in the chassis for the magnet to latch on to.  This is a 40 pound pull magnet, so I think we can get good performance out of this one...

DreamThinkBuild

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Re: Dia. Mag. Alternator
« Reply #175 on: April 04, 2011, 04:53:47 AM »
Hi Z.Monkey,

Very good work for a prototype. Must of been a lot of work to get those cuts and not cut through into the other side(especially aluminum), that takes some skill without a 4 axis milling machine. I used to run a VF-2 4 axis mill at my brother in-laws shop before I messed up my hand.

Anyway, keep up the great work.

z.monkey

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Re: Dia. Mag. Alternator
« Reply #176 on: April 04, 2011, 11:47:49 AM »
Very good work for a prototype.
Thank you.  A few more upgrades and I'll be able to convert my mini-mill into a legitimate mill...
I need more vertical space now, the 12" bench top drill press.  You can see there is not much room there...

phoneboy

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Re: Dia. Mag. Alternator
« Reply #177 on: April 04, 2011, 07:31:40 PM »

z.monkey

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Re: Dia. Mag. Alternator
« Reply #178 on: April 05, 2011, 12:06:02 PM »
Nice work!
Thanks Phoneboy.  I love Popular Mechanics.  My Grandfather had stacks of old copes in his garage, plus a whole lot of tools, so your link there is kinda nostalgic for me.  Trying to remember...  I think it was 1978 when I started building stuff and paying attention to things like Popular Mechanics...

Those old ads...  LOL!  Some of that stuff is still in Popular Mechanics...

z.monkey

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Re: Dia. Mag. Alternator
« Reply #179 on: April 08, 2011, 11:51:48 AM »
I put some windings on the DiaMag7 last night.
I resisted the urge to cleanup these plates more, and break the edges of the aluminum.
Yep, shoulda done that...

Although this coil looks pretty, its useless because its all shorted out.  And I mean everything.  The polyphase windings are more labor intensive than bobbin windings.  This means more contact with the core material and stress on the wire during the winding process, and then add in the sharp sheet metal edges, and you get thoroughly shorted out coils...

Then also there is the other problem, the lump of wire that is setting right in front by the axle.  There is a way to make this look better as the coil is designed, which is to wire the second phase the other way.  This would flatten that mass of wire somewhat,   But the wire is still in the way of the axle, and the magnet is stuck in there.  You would have to unwind the coil to replace a bearing, or the magnet.  That's not fun...

I could cleanup the whole mess by going to a Multi-Pole design, where I have more room to make windings, but then I am abandoning the whole DiaMag concept.  The diameter of the stator and windings would have to increase, and then add 8 or 10 poles on the stator.  Then the windings for each set of poles sit in a fraction of the diameter, and the wires would not have to traverse half of the diameter of the alternator...

The more I work on this thing, the more it is turning into a regular alternator...