Hi,
I have an unstable nonlinear plant in Simulink which I am linearizing around an operating point using Matlab's linmod function.
My question is in the validation of the linear model:
Since the system is open-loop unstable, I am finding it difficult to validate the linear model I produce by just running the simulation open-loop (I am guessing the difficulty arises from the fact that the simulation departs very quickly from the region where the linear model is valid). Is there anything fundamentally wrong with closing the loop on the nonlinear system to stabilize it and using the same loop on the linear system to compare the closed-loop performance and see if they are close... that way, if the closed loop performance is similar and they both have the same loop wrapped around them, then the dynamics must be similar?
Any other suggestions on how I can validate a linear model in this situation?
Thanks!