• State Resolved
  • Locked Locked
  • Replies 1 reply
  • Subscribers 82 subscribers
  • Views 631 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.

Original question:

Digital FOC motor control

BLDC FOC Q-D Axis Controllers Approaches

user6456504
Prodigy 75 points


Hi, I want to implement a FOC controller for the BLDC motor using DMC blocks. I have designed our control loops and tested them, it seems working but not very well. I have confused about Iq and Id saturation limits and tuning.

First of all, I have seen a few examples in which they are using the same PI params for both Iq and Id axis. But in some articles, they are not using the same PI parameters and they are tuning both of them separately. What is the difference between these two approaches?

The second question is related to Iq-Id Saturation limits. I have seen a few examples that they are limiting the controller with saturation voltage. As far as I know, Saturation voltage is related to inverter and PWM shape. I mean for SVPWM, Inverter_Voltage/sqrt(3) and for SPWM Inverter_Voltage/sqrt(2). But some other examples, they are implementing motor's stall torque as Iq saturation limit and, flux linkage for Id saturation limits.

As far as I can see, there are too many approaches but I couldn't find what is the difference between these approaches exactly and for this reason, I am confused a bit about which one is more suitable for me.

Thank you for your suggestions!

  • 0
    TI__Guru** 116090 points

    1. That depends on the motor. You might use the same parameters for Id and Iq controllers if the motor is an SPM, but you can use different values if it's an IPM motor.

    2. Using the current and voltage circle is a generic method in the TI reference design. The other approaches can be used also that depend on the control algorithm. You might find a detailed description of the motor control knowledge in some textbooks.