• State TI Thinks Resolved
  • Locked Locked
  • Replies 1 reply
  • Answers 1 answer
  • Subscribers 62 subscribers
  • Views 1531 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.

control theory and the PFC tuning of UCD3138

Keith Keller
Expert 7230 points
Other Parts Discussed in Thread: UCD3138

Hello,

Customer has a couple of questions related to the control theory and the PFC tuning of UCD3138.

Following the literature SLUA709 by TI for the PFC tuning and in reference to the control theory literature UCD 3138 by TI, It is my understanding that the computation algorithm for the Kp,Ki and Kd coefficients for the current and the voltage loop is done as stated in the control theory. But for the initial tuning of the current loop using a venable I see that the Kp Ki values have been set to 50 and 10.

On trying to do the back calculation with the given power stage parameters I have a variation from what is stated in the control theory literature.  It will be great if you can let me know on how these initial coefficient values are chosen for the tuning procedure.

Attached with this message is the control theory and the SLUA709 literature which I am referring.

Thank you.

PF_tuning_slua709.pdf

1727.UCD3138 Control Theory.pdf

 

  • 0
    TI__Expert 7310 points

    Hi,

    The purpose of  SLUA709 is tuning a PFC with the help of Venable. The mathematic model of PFC is not used as stated in the control theory. Therefore the initial PID coefficients are chosen by trial. The goal is trying different Kp, Ki such that the Bode Plot in the GUI shows enough phase margin and relative low bandwidth initially.