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RPM vs Torque, I, Mech HP, Eff, and Fp of an Induction Motor

  1. Apr 22, 2012 #1
    I need to create graphs of:

    3 Phase Torque vs RPM
    Current vs RPM
    Mechanical Power (HP) vs RPM
    Efficiency vs RPM
    Power Factor vs RPM

    for Slip between nearly 0 and 1 for a 5HP, 60 hz, 440Vac, 4 pole, 3 phase induction motor.

    I'm having trouble finding equations online relating relating these values. Can anyone give me a pointer in the right direction as to what equations I need to start with?

  2. jcsd
  3. Apr 23, 2012 #2
    Try to google for the equvivalent circuit for induction motor. There you will have all the equations you need, presuming you have the values for the motor impedances.
  4. Apr 23, 2012 #3

    jim hardy

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    Science Advisor
    Gold Member

    see if this link is any help


    there's no one minute answer. The size and shape of the rotor bars is designed to give the desired speed-torque curve. There are four basic curve shapes A through D depending on the nature of the load to be driven. Starting torque and pull out torque are main points of interest.

    Try google 'motor curve images ' and a quadratic curve fit to one that looks appealing.
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