Step response of Estimated model in SID toolbox.

Hello, I am trying to find model of my system using matlab's system identification toolbox. why i get step response of estimated model which settles at 0.05 instead of 1. Model shows good fit to validation data but residual analysis is bad. Thanks.

Answer 1

[Ameer Hamza]

It tells that the step input in the identification process has a magnitude of 20. Therefore when you apply a step signal with the magnitude of 1 it settles at 0.05. Either you can increase the magnitude of step input, multiply the obtained model by 20 or rerun the identification process with the input value normalized to 1.