Residual Analysis, Poles and Zeros of a MIMO System

Dear Matlab community

I've done system identification with multiple input, multiple output model data. Now, I am looking for a way to investigate the identified MIMO system by residual analysis and zeros and poles.

Is there a function to do residual analysis and zeros and poles location for MIMO systems?

Best regards

Benjamin

Answer 1

[Amey Waghmare]

Hi,

As per my understanding, you have modelled a MIMO system using multiple input multiple output data, and you want to analyze the model using poles and zeros, and validate the model using Residual Analysis.

In order to analyze and validate the model, you can use ‘System Identification App’ from System Identification Toolbox.

To load the model in the app, please follow the below mentioned steps:

1. Load the identified MIMO system and MIMO data in the MATLAB workspace. You can use ‘tf’, ‘ss’ or ‘idss’ commands to create model object. Here is link to the documentation: https://in.mathworks.com/help/ident/ref/idss.html
2. Launch the ‘System Identification App’ using the following command in the command window,
3. >> systemIdentification
4. Import the data and identified MIMO model using the drop-down at the top in the app.
5. To view the Zeros and Poles of the system, select the ‘Zeros and poles’ checkbox at the bottom of the app.
6. To perform the residual analysis, select the ‘Model resids’ checkbox at the bottom of the app.
7. A new window will open. To view the plot for a specific input-output pair, click on the channels tab on the top pane of the window and select the desired channel.

For more information, please refer the documentation,

• System Identification Toolbox: https://in.mathworks.com/help/ident/getting-started-1.html
• How to Plot Residuals in the App: https://in.mathworks.com/help/ident/ug/how-to-plot-residuals-using-the-app.html
• How to Plot Residuals at the Command Line: https://in.mathworks.com/help/ident/ug/how-to-plot-residuals-at-the-command-line.html

Hope this resolves the issue.

[Benjamin Pommer]

Thank you very much.