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Problems with idnlgrey object simulation

Asked by Pierangelo

Pierangelo (view profile)

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.



Pierangelo (view profile)

1 Answer

Answer by Arkadiy Turevskiy

Arkadiy Turevskiy (view profile)

on 15 Feb 2013
Edited by Arkadiy Turevskiy

Arkadiy Turevskiy (view profile)

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


Pierangelo (view profile)

on 17 Feb 2013

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

Arkadiy Turevskiy

Arkadiy Turevskiy (view profile)

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