If you do not specify a Padé order for a block, Control System Designer uses exact
delays by default when possible.
However, the following design methods and plots do not support systems with exact time
delays:
- Root locus plots
- Pole-zero maps
- PID automated tuning
- IMC automated tuning
- LQG automated tuning
- Loop shaping automated tuning
For these design methods and plots, the app automatically computes a Padé
approximation for any exact delays in your model using a default Padé order.
To specify the default order, in Control System Designer, on the Control System tab,
click Preferences.
In the Control System Designer Preferences dialog box, on the Time Delays tab, specify
one of the following:
- Pade order — Specific Padé order.
- Bandwidth of accuracy — Highest frequency at which the approximated response
matches the exact response. The app computes and displays the corresponding Padé
order.
Designing Compensators for Plants with Time Delays