Load torque vs Transient torque for PMSM motor coupled with VFD

    • ranjanpal999


      I made a PMSM model and implemented applied load torque = -3Nm. Negative sign has been applied as per following discussion: https://forum.ansys.com/discussion/12664/electromagnetic-torque-vs-load-load-torque-in-ansys-maxwell

      The PWM model for VFD has been referred from the inbuilt example as per discussion here: https://forum.ansys.com/discussion/26927/co-simulate-ansys-simplorer-and-ansys-maxwell-for-3-ph-pmsm-motor#latest

      The expected value graph of Transient torque produced by the motor should have been +3Nm. However, the value that I see is -0.25Nm as shown below:

    • Navya C
      Ansys Employee

      Since I don't know what is your exact design/model and setups and since you are using a drive control in your design I suggest you look at the mechanical transient setup topics in Ansys Maxwell help.
      The following screenshot may help you
      Regards Navya
    • HDLI
      Ansys Employee
      Hello ranjanpal999 Here are some information.
      1). PM motor is synchronous machine, so synchronous speed need to match current frequency in the simulation.
      2). The mechanical transient process could not be performed to match the load for the PM motor, because the torque of the PM motor is determined by the current and phase angle, not load in the simulation. The current control or speed closed loop control are required.
      A example is in ...\Examples\Twin Builder\Applications\PowerSystem\PMSM_SpeedControl_EMI.aedt

    • ranjanpal999
      Hi HDLI Thanks a lot for your suggestions. I understood what you said.
      Now, if I want to put a sinusoidal load torque, is there any way out to do so by changing current/phase angle?
      I opened up a discussion here: https://forum.ansys.com/discussion/comment/121479#Comment_121479
      What we expect is electromagnetic torque should also have followed a sinusoidal pattern.
      However, electromagnetic torque produced is still a horizontal straight line.
      Could you please suggest where am I going wrong ?

Viewing 3 reply threads
  • You must be logged in to reply to this topic.