Hi, I'm implementing some MPC Pro single in single out controllers at a project. These control loops have some dead time dominant processes with pretty long time to steady state, and so far the results are, well,...impressive.
Some of the processes are a integrating, and I was wondering about the adjustment of the ROTATION_FACTOR. I see that books online briefly touches on it, and says that the error is compensated every scan with a "shift" of the output prediction that works well for regulating type processes. But it says this shift has special effects on integrating processes that must be accounted for. There's also this relationship mentioned, where Shift Factor + Rotation Factor = 1. Books Online says "The Rotation Factor is the Integrating Gain in the period of one MPC scan for unmeasured disturbances and process model mismatch; usually in the range 0.0 to 0.1." After looking at the MPC Pro and MPC Plus blocks, I see that the default value for ROTATION_FACTOR is 0.05. However, I'm still not clear what to set it to for these different applications.
So, how does one apply and adjust the Rotation Factor, particularly for integrating processes? Is the range of 0.0 to 0.1 for regulating type processes or integrating as well? Is the range strictly between 0.0 to 0.1? And if not, what happens outside this range? Is there a rule of thumb the experts have for its use?
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