MATLAB >> Simulink S-domain Transfer function to Z-domain Transfer function

by Fred Lawton » Thu, 09 Jul 2009 00:34:20 GMT

Is there a block in simulink that can convert a transfer function in the s-domain to a transfer function in the z-domain?

If not, any recommendations on how to implement a simple solution?

MATLAB >> Simulink S-domain Transfer function to Z-domain Transfer function

by Phil Goddard » Fri, 10 Jul 2009 10:22:01 GMT


Assuming your transfer funtion is LTI (linear, time invariant) then there are functions within the Control Toolbox that will do the transformation for you.

If you don't have Controls Tbx then do a search for Tustin or Bilinear Transform and write some MATLAB code that does the conversion prior to running the simulation, and have a discrete transfer function block in your model use the results.
The transformation isn't difficult to implement.

Phil.

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