Ziegler-Nichols controller for second order processes. The controller is based on forward rectangular method of discretization replacing derivation by a four-point difference.
Transfer function of the controlled system:
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Vector of identification initial parameter estimations:
Controller specific parameters:
None.
Control law:
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where ek is control error ( ). This form of control law can be transformed to feedback form:
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Controller parameters are then calculated using following equations:
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Variables and are ultimate gain and ultimate period respectively.
Source code:
sid |
on-line identification s-function |
zn2fpd |
function for computation of controller parameters |
scfpd |
controller s-function |
See also:
On-line identification methods