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How to create a complicated transfer function?eg.customize a transfer function?

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The transfer function I want to create is like this, how? 

I would appreciate it if you answer me.

asked May 18, 2022 by fire (73 points)

1 Answer

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Best answer

The e^(-Td*s) portion of your model in the time domain is a time delay where y(t)=u(t-Td).  Therefore you can cascade a "Transport Delay" block with a "Transfer Function" block to implement the H(s)=w*e^(-Td*s)/(s+w) portion of your transfer function.

The other insight required to implement this transfer function is to observe that C(s)=K/(1-H(s)) represents a positive feedback loop with H(s) being the feedback transfer function. 

The image below shows how one would go about deriving the transfer function.  First would be to evaluate the performance without the exponential/delay term (top model), breaking the transfer function up into an equivalent feedback loop based implementation (middle), and then by inserting the delay into the feedback path (bottom).

answered May 18, 2022 by Bryan Lieblick (2,065 points)
selected Jul 12, 2022 by fire
HI,I appreciate that your answer solved my question, thank you!

Have a good day!
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