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Is there a resultant holding torque in the rotor?

  1. Aug 3, 2015 #1
    Hi, sorry for the title. I struggled to accurately describe my question in a short sentence.

    I'm trying to understand if there would be a holding torque or not in the following scenario.

    I'm referring to a motor which has a central stator and two permanent magnet rotor plates on either side to help visualise where I'm coming from.

    In an axial flux coreless motor there is a wire (in the stator) traveling upward through a magnetic field between a pair of north-south magnets (rotor). This same wire then skips a pair of magnets and travels back down through a pair of, again, north-south magnets.

    When a current flows through the wire, to my mind the rotor will be trying to turn both clockwise and anticlockwise due to lorentz force. Will this result in a holding torque or will the forces some how cancel out resulting in no holding torque?

    I don't (edit) think there would be a holding torque. Please enlighten me! Thanks so much for your input.

    Edit - Same scenario as above but now wires are moved apart so that they lie in the transition between two pairs of magnets of opposite orientation. Now when an external torque is applied to the rotor the lorentz force is increased in one or the other pairs of magnets which resists the external torque. Am I correct?

    Last edited: Aug 3, 2015
  2. jcsd
  3. Aug 8, 2015 #2
    Thanks for the post! This is an automated courtesy bump. Sorry you aren't generating responses at the moment. Do you have any further information, come to any new conclusions or is it possible to reword the post?
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