Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Equivalent Circuit for a CSCR Single Phase Induction Motor

  1. Jan 19, 2016 #1
    I have created a circuit diagram for a single phase CSCR induction motor, but only for the purpose of calculating start-up current (i.e. motor speed is at, or very near, zero RPM). I have created this diagram because: 1) I do not have the tools & knowledge required to generate the Steinmetz equivalent circuit with the capacitors included; and 2) The values for each of these circuit elements can be measured using an LCR meter (except for my beta term).

    Please review the attached circuit diagram and let me know if you find anything incorrect. Or, if it looks like this is a reasonable approximation for near zero speed currents then please give me a confirmation.
    The beta term I have in the diagram is something I conjured to represent the magnetic flux that the roto bars consume. My idea is that the measured inductance of each stator coil will be greater than the actual stator coil inductance during the start-up event because the LCR meter does not pass a sufficiently large current that a significant portion of the resulting magnetic field would pass through the rotor bar loops. For one motor tested on one power supply, I have found that my calculated start-up current is within 3% of the measured start-up current when I set beta = 50%. Does it make sense that, during the start-up event, the rotor would consume half of the magnetic flux generated by the stator coils?

    Thank you in advance for your help!

    Attached Files:

  2. jcsd
  3. Jan 24, 2016 #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?
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook