Author Topic: The Ultimate Motor Selection (COPPER)  (Read 4931 times)

Offline Ivan

  • Administrator
  • Senior Member
  • ****
  • Posts: 865
  • Country: us
    • Ivan's Garage
The Ultimate Motor Selection (COPPER)
« on: October 12, 2013, 06:04:38 AM »
What is a high Efficiency motor.

This is 3 videos on copper rotors motor selection.

I keep looking at a high efficiency 10-hp baldor to put in my water jacket,
but at a cost of 4k bucks plus I would have to rewind it.

This is the motor I want It is NOT copper:Click Here


<a href="http://www.youtube.com/v/sFWpzzh8l00" target="_blank" class="new_win">http://www.youtube.com/v/sFWpzzh8l00</a>


<a href="http://www.youtube.com/v/_PDoAvOA18E" target="_blank" class="new_win">http://www.youtube.com/v/_PDoAvOA18E</a> 


<a href="http://www.youtube.com/v/-hZOQaePG1U" target="_blank" class="new_win">http://www.youtube.com/v/-hZOQaePG1U</a> 
:co<:  If you bought just one or two extra can goods a week and donated to a food bank   Nobody would go hungry.

Offline mizlplix

  • Administrator
  • Senior Member
  • ****
  • Posts: 1443
  • Country: us
  • "The more you look, the more you find."
    • The old  build thread....
Re: The Ultimate Motor Selection (COPPER)
« Reply #1 on: October 13, 2013, 05:15:25 AM »
Copper rotors and their construction
___________________________________________________________________________ ________________________________

Lately, Ivan and I have been discussing copper rotors.  They are a really nice piece
and a really good performance/efficiency boost over an aluminum one. 

The possibility of "finding" a core motor to rewind for EV usage is pretty much
a once-in-a-lifetime deal.  But maybe making one is not so far fetched. 

After watching a really nice video of rotor pouring, it becomes clear that the
"backyard" method will not suffice to make a really good one.

But, what about an alternate method?  Hand winding the rotor like we do stators?

The end rings must, by nature, be able to carry huge currents and make all of
the slot wires in parallel for this to work.

So, here I propose for the first time, one construction method:


1. Whereas the rotor plates could be bought water-cut and brand new, the
rotor shaft be made from a shaft blank, simple economics would forbid this
from happening.  My quick and dirty estimate comes up to $1,500 USD in
pieces before construction even begins.

We need another/ affordable way.

2. An old aluminum rotor assembly from your donor motor is already
together, on hand and going to be going to scrap if not used.

I propose that a small propane fired kiln be made from simple stacked
bricks and fire clay, one like is used every day to melt aluminum scrap
to make simple castings. I should be able to produce a constant temperature
great enough to remelt the aluminum in the rotor.

If a lathe were used to remove the end rings, then only the thinner
aluminum bars would remain in the slots.  A thin cross section that would be
capable of being melted out without harming the steel rotor lamination's. 

Propane fuel is physically impossible of the much greater temperatures of
even harming steel. 

Should this work, it would provide a nice clean rotor section that is ready
for copper to be added.

3. Pouring molten copper would be a complex and challenging venture, but
adding the copper in strips, wires and pieces and high temperature copper
braising it together is not an impossible ideal for a DIY project.


Well, enough for now.  Think about it and put down your thoughts.

Miz
1930 Ford Speedster, AC50, full manual powerglide, 6.14gears, 38-130AH CALBs.

Offline mizlplix

  • Administrator
  • Senior Member
  • ****
  • Posts: 1443
  • Country: us
  • "The more you look, the more you find."
    • The old  build thread....
Re: The Ultimate Motor Selection (COPPER)
« Reply #2 on: October 13, 2013, 05:16:42 AM »
Starting with a bare rotor, we could cut 1/4" thick copper "rings" to go on the rotor
lamination stack ends.

Cut slots in it to duplicate and match the rotor slots.  Temporarily afix it with
screws to hold it in place during construction.

THEN hand wind the slots with bare copper wire going around the slots and
back into the adjacent slot continuously until they are full and packed tight.

The ends will need solid braised to be conductive, but need not be uniformly
smooth because they will not be doing the 10,000 plus RPM of a Tesla.

A lathe cleanup of the outside and a re-balance would  complete the assembly.

It does not sound too far fetched, does it?

Miz
1930 Ford Speedster, AC50, full manual powerglide, 6.14gears, 38-130AH CALBs.

Offline HighHopes

  • Senior Member
  • ****
  • Posts: 224
  • Country: ca
Re: The Ultimate Motor Selection (COPPER)
« Reply #3 on: October 13, 2013, 06:51:52 PM »
are you suggesting a wound rotor instead of squirrel cage? 
http://www.allaboutcircuits.com/vol_2/chpt_13/8.html

ps. there's no way i'm going to have a backyard foundry.  i'm glad you are looking for alternatives

Offline Ivan

  • Administrator
  • Senior Member
  • ****
  • Posts: 865
  • Country: us
    • Ivan's Garage
Re: The Ultimate Motor Selection (COPPER)
« Reply #4 on: October 13, 2013, 07:00:03 PM »
are you suggesting a wound rotor instead of squirrel cage? 
http://www.allaboutcircuits.com/vol_2/chpt_13/8.html

ps. there's no way i'm going to have a backyard foundry.  i'm glad you are looking for alternatives

No, on the wound rotor we would just pull in straight wires through the slots,
end plate to end plate and silfloss all the connections, just fill the slots
with copper strand.  Don't have a clue if it would work.
:co<:  If you bought just one or two extra can goods a week and donated to a food bank   Nobody would go hungry.

Offline HighHopes

  • Senior Member
  • ****
  • Posts: 224
  • Country: ca
Re: The Ultimate Motor Selection (COPPER)
« Reply #5 on: October 13, 2013, 08:42:24 PM »
so you cut off the aluminum end rings leaving just the rotor shaft, steel lamination core, aluminum squirrel cage bars.  then you put that into some sort of heater to melt only the aluminum (like this get up which has duct tape.. so you know its good http://www.instructables.com/id/Quick-cheap-and-dirty-aluminum-melting-furnace-s/)

once aluminium is melted now you have room to put in your copper wire and attach this to your own end plates? 

can you get copper wire bare, without enamel?  the smaller strand the better the fill factor?  anyway, seems like a great idea to try!

*** edited:  oops, i put aluminium wire when i meant copper wire. 

Offline BIGslim

  • Member
  • **
  • Posts: 31
  • Country: us
  • One Shock Away
Re: The Ultimate Motor Selection (COPPER)
« Reply #6 on: October 13, 2013, 09:28:41 PM »
I just bought a weber kettle.  Grab my wife's hair dryer and I'm in.

Offline mizlplix

  • Administrator
  • Senior Member
  • ****
  • Posts: 1443
  • Country: us
  • "The more you look, the more you find."
    • The old  build thread....
Re: The Ultimate Motor Selection (COPPER)
« Reply #7 on: October 14, 2013, 12:39:17 AM »
Not aluminum wire.....COPPER wire. (and copper end plates.)

YES, version one could have a continiously wound wire rotor with the end loops silver braised to the plates.

Version two could have single wires layered into the slots before being braised on the ends to the plates.

But you get your copper fill and solid ends...

No, I do not have a guess if it will run either.

I do have a spare 10HP motor to try it on sometime.

Miz
1930 Ford Speedster, AC50, full manual powerglide, 6.14gears, 38-130AH CALBs.

Offline mizlplix

  • Administrator
  • Senior Member
  • ****
  • Posts: 1443
  • Country: us
  • "The more you look, the more you find."
    • The old  build thread....
Re: The Ultimate Motor Selection (COPPER)
« Reply #8 on: October 14, 2013, 12:50:38 AM »
One note:  These motors may be standard duty and not inverter duty, but they are only a few percent off of the efficiency.  We assume it to be possibly different steel alloy used in the plates.

I do not think the added cost of the inverter duty motor is worth the few percent difference in efficiency.  And we do not know for sure if the inverter motors actually have a copper poured rotor.

From what I have read, I am guessing, but it seems that the biggest difference in a copper poured rotor motor is not in a big performance boost alone, but rather a small performance boost and a small reduction in operating current.

Would it be worth all of this extra work?  Who knows.   But, it would be an interesting experiment to see.
First, rewind the motor to run off of a Curtis controller and dyno it.

Then perform the above operation to convert it to a copper composite rotor and re-dyno it.

I am afraid it will be down the road a little though...LOL

Miz
1930 Ford Speedster, AC50, full manual powerglide, 6.14gears, 38-130AH CALBs.

Offline HighHopes

  • Senior Member
  • ****
  • Posts: 224
  • Country: ca
Re: The Ultimate Motor Selection (COPPER)
« Reply #9 on: October 14, 2013, 06:34:51 AM »
that's OK, its fun to think about where you want to go with the technology you are developing.  perhaps this experiment is the next logical step for you.  its the nature of a hobby  :)

Offline BIGslim

  • Member
  • **
  • Posts: 31
  • Country: us
  • One Shock Away
Re: The Ultimate Motor Selection (COPPER)
« Reply #10 on: October 14, 2013, 04:00:14 PM »
I wonder if these guys have a US distributor?

http://www.favi.com/ang/index.php

Offline mizlplix

  • Administrator
  • Senior Member
  • ****
  • Posts: 1443
  • Country: us
  • "The more you look, the more you find."
    • The old  build thread....
Re: The Ultimate Motor Selection (COPPER)
« Reply #11 on: October 14, 2013, 07:21:44 PM »
They seem to have a handle on transportation rotors.  ....Replacing aluminum rotors.....too
good to be true.  Available in medium to large runs only...and in France.

Here is a good read on rotor construction.  It seems that fabricated copper rotors are common before pressure injection casting was invented. 



Miz 
1930 Ford Speedster, AC50, full manual powerglide, 6.14gears, 38-130AH CALBs.

Offline few2many

  • Senior Member
  • ****
  • Posts: 128
  • Country: us
Re: The Ultimate Motor Selection (COPPER)
« Reply #12 on: October 14, 2013, 07:46:25 PM »
Do you have to melt out the aluminum? Can the end rings be lathed off, then the slots or bars be drilled or machined out? Then, press copper bars in and weld on the end rings.

Offline BIGslim

  • Member
  • **
  • Posts: 31
  • Country: us
  • One Shock Away
Re: The Ultimate Motor Selection (COPPER)
« Reply #13 on: October 14, 2013, 08:27:10 PM »
I would start from scratch.  Would it be better to press the plates then drill, or drill than press?  None of this is practical for mass production, but may work for DIY.

Offline mizlplix

  • Administrator
  • Senior Member
  • ****
  • Posts: 1443
  • Country: us
  • "The more you look, the more you find."
    • The old  build thread....
Re: The Ultimate Motor Selection (COPPER)
« Reply #14 on: October 15, 2013, 12:01:00 AM »
"Do you have to melt out the aluminum? Can the end rings be lathed off, then the slots or bars be drilled or machined out? Then, press copper bars in and weld on the end rings."

Read post 2 above. (reply 1)

Lathe off end rings.
Melt out bars. Making sure the plates do not move.
Attach new end rings with slots to match.
Pack slots with copper wire. Packed in with a hammer and mandrel.
Silver braise (Whatever you want to call it) end rings to the wire in the slots.
Lathe clean up. Rebalance. Assemble.

Fabricated rotors were common before modern metal injection was developed.

 


1930 Ford Speedster, AC50, full manual powerglide, 6.14gears, 38-130AH CALBs.