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TMS320F28069: TMDSHVMTRINSPIN

Part Number: TMS320F28069

Hi team,

Here's an issue from the customer may need your help:

In Lab5b, during the test it was found that the speed reference value for PID control of the speed loop was 52707179 and was constantly changing:

But the customer set it at 1677721, so they would like to know why they are different?

Could you help check this case? Thanks.

Best Regards,

Cherry

  • Hi Cherry,

    I have assigned this to our InstaSpin expert, they should get to you shortly

    Regards,

    Peter

  • It's a temporary variable in this function, you can get the right value when the code is executing. You may check the variables in trajectory object or the reference value of speed PI controller object in expression watch window.

    ctrlHandle->traj_spd.targetValue

    ctrlHandle->traj_spd.intValue

    ctrlHandle->pid_spd.refValue

  • Hi,

    Thanks for your help!

    The customer has checked these variables, but there is still a multiple relationship.

    Below is the set reference speed (0.1 KRPM):

    But the variables you mentioned are all 0.2 KRPM as the figure below, which is a 2x relationship to the customer's set value, why is this?

    And the customer has also checked the motor speed is 0.1KRPM.

    Thanks and regards,

    Cherry

  • Cherry,

    Yanming is out of office today. Please expect response by Monday.

    Thanks & Regards,

    Santosh

  • The project runs well without any errors. The unit of these variables are different. The unit of gMotorVars.SpeedRef_krpm is "rpm", the unit of the other variables are PU format. The value of the gMotorVars.SpeedRef_krpm need to be converted to the PU format.

    You may find the conversion code as below in the lab.

    // set the speed reference
    CTRL_setSpd_ref_krpm(ctrlHandle,gMotorVars.SpeedRef_krpm);