I'm trying to make a PI control model with Control and Design in labview 2009. I'm tyring to create the following transferfunction:
But labview adds by itself an extra z^-1 in the Numerator
See the attachment what I have tried. I first want to create 1+(1/(1-z^-1)). What I'm I doing wrong ?
The two expressions "1+(1/(1-z^-1))" and "(2-z^-1)/(1-z^-1)" are equivalent to one another. They just have the terms rearranged. Since LabVIEW expresses a transfer function as a numerator and denominator, it is drawing the function as "(2-z^-1)/(1-z^-1)". You aren't doing anything wrong.
Ah, stupid off me. Matlab gives the same awnser.
Another question, how do I implant in control and design a Saturation block ? In Simulation there is a standard block but nog for control and design.
I'm trying to determine de P an I values for an embedded PI motor controller.
The Control Design VIs create transfer functions, state-space, and zero-pole-gain models, which are all linear, time invariant (LTI). Since saturation is nonlinear, it cannot be represented by an LTI model. I suggest using a saturation block in a simulation loop.