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Matlab outputing wrong transfer function?

Jason D — Mon, 19 Oct 2009 18:22:35 -0400

I was testing Simulink and I placed a 'du/dt' block between and input and output block, then ran

[A,B,C,D] = linmod('system')
[num, den] = ss2tf(A,B,C,D)

this returns the transfer function as 0/1. Shouldn't it be s/1 ?

Re: Matlab outputing wrong transfer function?

Phil Goddard — Mon, 19 Oct 2009 19:40:19 -0400

Open the derivative block and press the Help button to read the doc.
It explains why the derivative is zero, and has links to several topics related to why you should avoid using derivative blocks and how you may be able to change your model to avoid them.

Phil.