zn3ast

Astrom's controller for third order processes.

Transfer function of the controlled system:

Vector of identification initial parameter estimations:

Controller specific parameters:

Parameter

Description

alfa - filter constant

Filtration coefficient a used by filter of process output signal. The time constant of the filter is:  where usually 3 < a < 20

beta – weight

The weight b of reference signal in proportional component of controller. The weight should be 0 < b £ 1

Control law:

where:

where controller parameters ,  and  are calculated using following equation:

Variables  and  are ultimate gain and ultimate period respectively.

Source code:

sid

on-line identification s-function

zn3ast

function for computation of controller parameters

scast

controller s-function

See also:

On-line identification methods

Computation of ultimate gain and period

List of common controllers parameters