What is Induction motors: Definition and 27 Discussions

An induction motor or asynchronous motor is an AC electric motor in which the electric current in the rotor needed to produce torque is obtained by electromagnetic induction from the magnetic field of the stator winding. An induction motor can therefore be made without electrical connections to the rotor. An induction motor's rotor can be either wound type or squirrel-cage type.
Three-phase squirrel-cage induction motors are widely used as industrial drives because they are self-starting, reliable and economical. Single-phase induction motors are used extensively for smaller loads, such as household appliances like fans. Although traditionally used in fixed-speed service, induction motors are increasingly being used with variable-frequency drives (VFD) in variable-speed service. VFDs offer especially important energy savings opportunities for existing and prospective induction motors in variable-torque centrifugal fan, pump and compressor load applications. Squirrel-cage induction motors are very widely used in both fixed-speed and variable-frequency drive applications.

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  3. G

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  4. Mathew Joseph

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  5. G

    Induction Motors: Rotating Magnetic Field & AC Frequency

    Hi, Can I please ask how the rotating magnetic field (due to the 3 phase ac) is changed? Is it due to the frequency of the ac supply that it can speed up and therefore drag the rotor along due to induction. If it is due to the changing frequency input that mimics a faster rotating magnetic field...
  6. Osvaldo

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  7. R

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  8. P

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  10. G

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  11. srinaath

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  12. cnh1995

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  13. B

    Poles of AC Induction Motors

    Hello, I want to know determining the number of poles by inspecting coils inside the motor. Generally, there are formulas allowing us to plug a frequency, an rpm, and give off the number of poles, or we can just simply look at its nameplate. My reason for needing the inspecting is that my...
  14. D

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  15. S

    How Many Turns are Required for an Induction Motor in Different Voltage Levels?

    I want to known the stator design of an indiction motor. How may turns required for each pole. For exmple if a single phase motors is designed to run at 230v ac, how may turns required in each pole. If the same motor is designed to be run in lower voltage (say 110v ac or 12v ac) what will be the...
  16. ranju

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  17. T

    What is the required torque for a spinning flywheel?

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  18. W

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  19. N

    Understanding Rotor RMF in Squirrel Cage & Slip Ring Induction Motors

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  20. T

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  21. B

    Induction Motors: Power Consumed vs Power Delivered

    Hello The equation for power consumption of a three phase induction motor is given by the equation: P = sqrt(3)*V*I*(PF) Does this differ from the power that is delivered to the motor. For example, if a motor is running at 460 volts, 30 amps with a PF of 0.82, then the power...
  22. M

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  23. M

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    Homework Statement Here are a bunch of questions that I've attempted. I feel fairly confident with my answers, but I just wanted to make sure :) Thanks! a) calculate the synchronous speed, amount of slip and the percentage slip in a typical aircraft a.c., four pole, 400hz induction motor...
  24. V

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  25. H

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  26. A

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  27. M

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