• State Resolved
  • Locked Locked
  • Replies 3 replies
  • Answers 1 answer
  • Subscribers 83 subscribers
  • Views 437 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

TMS320F28069F: How to adjust Iq Id?

F.F
Genius 3095 points
Part Number: TMS320F28069F
Other Parts Discussed in Thread: MOTORWARE

Hi team:

I use f28069f to do FOC control. In current control mode, I use Iq to control the current of the motor in normal state. At present, I have a demand to add Id output control.

At present, I control the output of Iq when the motor is in normal operation, but if I want to increase the speed and add weak magnetic control, when should I control the output of Id to increase or decrease? It seems that it can't be increased or decreased rapidly, because it will generate a great back EMF to recharge the voltage system.

Best regards

  • 0
    TI__Guru** 116140 points

    You might add a ramp control for increasing/decreasing Id and Iq. And you should set a right Id reference for weakening control based on the spec. of the motor, the Id reference will be a negative value and will be changed according to the speed, dc bus voltage, and the output voltage to the motor during field weakening control. You could find some papers about field weakening control to design the control algorithm. The motor speed depends on torque current, load, and flux.

    Or you can refer to the lab09 in motorWare that shows a generic field weakening control method.

  • 0 in reply to Yanming Luo
    Prodigy 10 points

    Hello, I have a problem with lab09

    1. About the usage of "#define USER_MAX_VS_MAG_PU (0.6666) ":

    I want to know whether this parameter can be set to be larger than 0.6666? How much can be set to the maximum, and is there any special attention to this parameter adjustment?

    Can I add or subtract this value arbitrarily? Is there a slope limit for adding or subtracting this value? Or which data should I monitor to adjust the addition/subtraction slope?

    2. Using the above parameters (increasing the setting value) seems to achieve the effect of weak magnetic field pulling high speed. However, if you use the function "CTRL_setId_ref_pu()" at the same time to increase or decrease the setting of Id, what should you pay attention to? Place?

    Are there any slope limits for addition/subtraction, or what data changes need to be observed to increase or decrease in time.

    Thank you

  • 0 in reply to derlung chien
    TI__Guru** 116140 points

    1. No, the maximum value is 2/3 (0.666). We recommend you set the value is less than 0.574 and need to use lab10 with overmodulation if the value is greater than 0.5.

    Yes, you can, set the value by calling CTRL_setMaxVsMag_pu(CTRL_Handle handle,const _iq maxVsMag). Check the ctrl.maxVsMag_pu value. There is no slope control for this variable, you have to add this function by yourself since all of the example labs used a fixed value.

    2. I don't think so. The field weakening should be implemented by controlling the Id with a negative value for a PMSM. No such codes in the example labs, you have to add such ramp control by yourself.