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AC vs DC Motors

AC vs DC Motors

AC vs DC Motors

(OP)
I need to select a 1/2-3/4 hp electric motor to power a large battery powered cart. The cart will have laser scanners to detect potential obstructions and stop the cart as well as controls to synchronize it's speed and movement with the other carts. It will also only need to move for about 2 minutes at a time. I am not very familiar with the benefits of AC and DC motors so I would appreciate any input on the matter.
Thanks

RE: AC vs DC Motors

What is the total voltage of the battery pack?

RE: AC vs DC Motors

DC sounds like the natural choice if your service interval is as short as two minutes. There are lots of simple DC motors in the power range you mention. It depends somewhat on what battery voltage you have. I assume 12 or 24 V and there you have a very broad choice of economical and robust DC motors.

AC motors are sometimes preferred - mostly because they do not need much service (no brushes to replace) but with the two minutes operation, I do not think that you will need to change brushes in many years.

DC may not be the latest - but is still around. Mates batteries perfectly and is cheap.  

Gunnar Englund
www.gke.org
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100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...

RE: AC vs DC Motors

(OP)
Thanks, the battery pack hasn't been designed yet, it's all still in the early stages of design and I just wanted to have some input on which direction to go. Sounds like DC should work just fine. Thanks again!

RE: AC vs DC Motors

Just use a universal motor like is found in many drills, and other small applicances.

Best bet is to look at the surplus places for motors for project prototyping.

RE: AC vs DC Motors

A universal is maybe not the greatest choice for a traction motor - a series field would be my first choice followed by a compound design and then a PM type. Golf cart or a mobility scooter might be a good starting point to cannibalise.
  

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If we learn from our mistakes I'm getting a great education!
 

RE: AC vs DC Motors

You can find some pretty tough mobility scooter drives for cheap on ebay.  I did.  Remember the motorized couch?

They also get you an automatic band brake.

Keith Cress
kcress - http://www.flaminsystems.com

RE: AC vs DC Motors

I don't recall a motorized couch. I expect it did not sell because most couchs are so large in respect to the room size.
I guess it would help moving it in when new, and out when it becomes old.

Now I do know of the vibrating couch, but that would not be much good for this application.

There are premade wheel motor applications for use in robot construction.

RE: AC vs DC Motors

Looks like I could drive it to work, but it wouldn't fit on the elevator.

Back to the OP, my preference would be DC.

rmw

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