Simulink not recognizing blocks in the linearization path

4 views (last 30 days)
I am trying to simulate a MPC controller in a coupled tank plant but when I run the MPC toolbox my system is not being linearized. I was expecting matrices 2x2 for my state space system. I have attached the images of the screen of the model and the compilation from the control and estimation tool. Does anyone knows the reason why simulink is not linearizing this model?

Accepted Answer

Arkadiy Turevskiy
Arkadiy Turevskiy on 17 Apr 2014
I quickly tried setting up some values and linearizing plant model. My guess is that you are probably linearizing where your integrators are saturated, and therefore are getting zero linearization. Try to disable integrator saturation when designing MPC, then enable it back when running simulations.
  1 Comment
Matheus Damasceno
Matheus Damasceno on 17 Apr 2014
Yes, you were right, I just tried linearizing the plat without saturations and worked just as expected.
Thank you for your help.

Sign in to comment.

More Answers (1)

Arkadiy Turevskiy
Arkadiy Turevskiy on 17 Apr 2014
Hard to say exactly without having the model (can you attach it maybe?), but the likely scenario is that the root cause of the problem are the discontinuities in the model such as sign block.
A solution may be to specify custom linearization for such blocks as explained in the linearization troubleshooting section , specifically here .
  2 Comments
Matheus Damasceno
Matheus Damasceno on 17 Apr 2014
Edited: Matheus Damasceno on 17 Apr 2014
I see, I never thought about the discontinuity of the sign block. Ok, I just uploaded the model, meanwhile I will read the links you recommended and keep testing.
Arkadiy Turevskiy
Arkadiy Turevskiy on 17 Apr 2014
Can you also provide all the parameters used in the model?

Sign in to comment.

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!