Tune Compensator Parameters Using the SISO Design Tool

In this example, you get an overview of the steps for tuning compensator parameters. Before you begin, you need:

• A model in the MATLAB workspace representing your plant

• Design requirements for your system

To tune parameters:

1. Open the control design GUIs by typing the following in the MATLAB Command Window:

   sisotool

   This command opens the Control and Estimation Tools Manager and the SISO Design Tool, as shown in the following figure.

   

2. Define the control architecture for your system.

   1. In the Architecture tab of the Control and Estimation Tools Manager, click Control Architecture.

   2. In the Control Architecture dialog box, select the control architecture.

   3. Specify the sign of summing junctions as + or -.

   

3. Specify the plant model and initial guesses for the compensator elements in the control architecture.

   1. In the Architecture tab of the Control and Estimation Tools Manager, click System Data.

   2. In the System Data dialog box, browse for a model in the MATLAB^® workspace.

   

4. Design a compensator using automated tuning, for example PID Tuning.

   1. In the Automated Tuning tab of the Control and Estimation Tools Manager, select an automated tuning method.

   2. Specify tuning options.

   3. Click Update Compensator to tune parameters.

   

5. Evaluate the system's closed-loop performance.

   1. Plot the system response.

      1. In the Analysis Plots tab, select a plot type.

      2. Select the type of response for each plot.

      

   2. Display specific performance characteristic for your system. Compare values to design requirements.

      1. Right-click to select performance characteristics.

      2. Click on the dot that appears to view the characteristic value.

      

6. Refine compensator design using graphical tuning.

   1. Create plots for graphical tuning.

      1. In the Graphical Tuning tab, select the loop to tune in each plot.

      2. Select plot types.

       

      

   2. In a design plot, modify the compensator by adding poles, zeros, lead, and lag, for example. To do this, right-click to add dynamic elements in the controller structure.

      

   3. Add a new pole, for example, by clicking the pole location on the plot.

   4. Modify the compensator structure by moving the poles, zeros, and other dynamic elements directly on the plot.

      

7. Export the compensator to the MATLAB workspace for further analysis.

   1. In the Control and Estimation Tools Manager, select File > Export.

   2. In the SISO Tool Export dialog box, select the compensator.

   3. Click Export to Workspace.