Example: Adding a Complex Pair of Poles :: SISO Design Tool (Using the SISO Design Tool and the LTI Viewer)

Using the SISO Design Tool and the LTI Viewer

Example: Adding a Complex Pair of Poles

This example shows you how to add a complex pair of poles to the open-loop Bode diagram. First, type

load ltiexamples
sisotool('bode',sys_dc)

at the MATLAB prompt. This opens the SISO Design Tool with the DC motor example loaded and the open-loop Bode diagram displayed.

To add a complex pair of poles:

Select Add Pole/Zero and then Complex Pole from the right-click menu
Place the mouse cursor where you want the pole to be located
Left-click to add the pole

Your SISO Design Tool should look similar to this.

In the case of Bode diagrams, when you place a complex pole, the default damping value is 1, which means you have a double real pole. To change the damping, grab the red `x' by left-clicking on it and drag it upward with your mouse. You will see damping ratio change in the Status Panel at the bottom of the SISO Design Tool.

Using the Right-Click Menu to Design Compensators Viewing Loop Responses and System Data