MATLAB Answers


Problems with idnlgrey object simulation

Asked by Pierangelo
on 15 Feb 2013

Hi everyone,

I am trying to identify the parameters of a system using a non-linear greyBox object. My system is defined as a state-space and the estimation, run by means of 'pem' command, seems to give good results.

After the estimation process, I use the command 'compare' to have a look on the results with respect to the measured data, and this results good as well.

The problem appears when I simulate the greyBox object on Simulink. The outputs it gives are completely different from the ones given by 'compare', altough I use the same input data.

Why does it happen? Which outputs should I trust more?

Thank you very much.


1 Answer

Answer by Arkadiy Turevskiy
on 15 Feb 2013
Edited by Arkadiy Turevskiy
on 15 Feb 2013
 Accepted answer

This issue was addressed several times previously, here is a link to the question that was answered alerady. You need to set the initial states correctly. Take a look at function for doing that.



  1 Comment

Thank you very much Mr. Turevskiy. You were correct.

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