Simulink Control Design™ - MathWorks

For more information about the relative advantages of each method, see the Discrete PID

Controller block reference page.

When you update a PID Controller block or custom PID controller with tuned parameter

values, make sure the filter method matches.

Tunable: Yes

Dependencies

This parameter is enabled when the Time Domain is discrete-time and the controller

includes derivative action.

Programmatic Use

Block Parameter: FilterFormula

Type: character vector

Values: 'Forward Euler' | 'Backward Euler' | 'Trapezoidal'

Default: 'Forward Euler'

Target bandwidth (rad/sec) — Target crossover frequency of tuned response

1 (default) | positive scalar

The target bandwidth is the target value for the 0-dB gain crossover frequency of the

tuned open-loop response CP, where P is the plant response, and C is the controller

response. This crossover frequency roughly sets the control bandwidth. For a rise-time τ,

a good guess for the target bandwidth is 2/τ.

To perform PID tuning, the autotuner block measures frequency-response information up

to a frequency of 10 times the target bandwidth. To ensure that this frequency is less than

the Nyquist frequency, the target bandwidth, ωc, must satisfy ωcTs ≤ 0.3, where Ts is the

controller sample time that you specify with the Controller sample time (sec)

parameter. Because of this condition, the fastest rise time you can enforce for tuning is

about 1.67Ts. If this rise time does not meet your design goals, consider reducing Ts.

For best results with closed-loop tuning, use a target bandwidth that is within about a

factor of 10 of the bandwidth with the initial PID controller. To tune a controller for a

larger change in bandwidth, tune incrementally using smaller changes.

To provide the target bandwidth via an input port, select Use external source.

Programmatic Use

Block Parameter: Bandwidth

Type: positive scalar

16 Blocks — Alphabetical List