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Strong motor using permanent magnets?

  1. Jun 7, 2012 #1
    Greetings all.

    I was wondering if I could build a low energy consuming but a powerful motor using neodymium magnets and a AC electromagnet(for switching poles N>S>N>S,etc...)

    The magnetic field created by the electromagnet could potentially attract a large and stronge neodymium magnet in the motor and repel it quickly because the magnet itself is stronger then the electromagnet, resulting in a strong, less consuming motor.

    Electromagnets pull/repel force rated at : 5 lb
    Neodymium pull/repel force rated at: 20 lb

    Is all of that possibile?

    Thanks,
     
  2. jcsd
  3. Jun 7, 2012 #2

    phyzguy

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    Permanent magnet motors are "off-the shelf" items, so you are really re-inventing the wheel. Also, be aware that good motors today can be 90-95% efficient, so there really isn't much to be gained by making them more efficient.
     
  4. Jun 7, 2012 #3
    You didn't really answer the question... :confused:
     
  5. Jun 7, 2012 #4

    phyzguy

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    Maybe I didn't understand your question. I thought you were asking whether it was possible to build an electric motor by combining permanent magnets with electromagnets which are switched to change the polarity so that they alternately attract and repel the permanent magnets. The answer is yes, it is possible. It's called a permanent magnet motor and you can buy them from many sources. Then I thought that you were asking whether the use of permanent magnets makes the motor more efficient. The answer is maybe (I think), but motors are already very efficient so there isn't much to be gained. What other questions did you have?
     
  6. Jun 7, 2012 #5
    Thanks for everything, I believe the use of permanent magnets would lead us to higher efficiency then normal non-magnetic rotars.
     
  7. Jun 8, 2012 #6
    If you think about it... Most motors today induce a magnetic field on a metal. What if you induced an magnetic field upon another magnetic field from a permanent magnet! I'd think we would have consumed less energy "Input" and would get a promising result.

    What do you all think? Are permanent magnets motors stronger and better then the conventional ones?
     
  8. Jun 9, 2012 #7

    russ_watters

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    How much better than 95% are you hoping to get?!
     
  9. Jun 10, 2012 #8
    As high as I can get and I would doubt to get even close to 80% lol Im just experimenting around thats all.
    Shoot, if I got over 95% I'll be going all crazy!
     
  10. Jun 10, 2012 #9

    russ_watters

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    Staff: Mentor

    If you can't even get 95%, how is this endeavour even worth the effort? I thought your goal was to build a more efficient motor? :confused:
     
  11. Jun 10, 2012 #10
    Well look, that is my main goal but its kinda hard to do. I'd like to study this and maybe improve it gradually. Having a lot of options how to do so is kinda good for me it acts as a support for my goal.

    By experimenting a few things maybe I will stumble on something different and maybe in a year or two or 3,4,5 what ever reach my goal.
     
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