How to assign different prediction- and control sample times for Simulink (NL)MPC

I am currently working at controlling a dynamically fast-changing plant at a sample rate of 20 Hz. This Ts is set in the mpc object.

Now, I read in literature that it can be beneficial to let the controller optimize control signals for multiple timesteps in the future, before it reruns the optimization problem. For example; it calculates control signals every 1 s for 0.1 s intervals (so 10 values per calculation).

While searching how to implement this in Simulink, I encountered This document. p.5 states it is possible to set different control and prediction sample times (not horizon!). It also states "the prediction sample time and control sample time are often set to be equal or even treated as one parameter".

My question: 1. are the control and prediction sample times mentioned in the document those I am referring to? 2. Is it possible to implement this in Simulink? If not natively, is there another option that is not too complex to implement? What do you suggest?

I thank you!

Answer 1

[Emmanouil Tzorakoleftherakis]

For linear MPC, see answer here. For nonlinear MPC, it is simpler, the Nonlinear MPC block and the respective block for multistage nonlinear MPC give you the option to select different sample time for control and prediction. See here.