How does linmod2 order the states when the mdl contains a ss-block

Hi, my simulink model contains integrators and a ss-block (e.g. 2 states). When I use linmod2, I do not know the state-vector of the linearized model. How does linmod2 arrange the states in the state-vector, e.g. [integrator1output integrator2output state1fromssblock state2fromssblock] vs. [integrator1output state1fromssblock state2fromssblock integrator2output] Thanks for any reply!

Answer 1

[Ryan G]

You can use the Linearize command to obtain a state space system where the states are labeled. The big difference is the linearize function is part of the Simulink Control Design toolbox.

[Jörg]

Hi, thank you very much, but unfortunately, I don't have this Toolbox. Any other ideas? Jörg

[Ryan G]

You can use the following for state names with LINMOD but not LINMOD2.

sys_struc = linmod(gcs, x, u);

StateName will be part of the structure sys_struc along with the state matrices. You can find x and u by utilizing the trim routing.

[x,u,y,dx] = trim(gcs);

You can also get the states via:

x = Simulink.BlockDiagram.getInitialState(gcs);

You can utilize the state names inside of the state space model using the following command:

sys = ss(sys_struc.a,sys_struc.b,sys_struc.c,sys_struc.d,'StateName',sys_struc.StateName)

[Jörg]

Thank You!