How to input exponentials in transfer functions using Simulink?

This is my transfer function but I don't know how to input this on Simulink.

Answer 1

[Sam Chak]

Hi @Milca Munguia

You can insert the Transport Delay block (found in the Library of Continuous function blocks) after the transfer function.

https://www.mathworks.com/help/simulink/slref/transportdelay.html

See example here:

https://www.mathworks.com/help/simulink/slref/anti-windup-control-using-a-pid-controller.html

Answer 2

[Walter Roberson]

If this must be implemented as transfer functions then you will need to copy the transfer function block several times, set the Input Delay differently on each copy, and then add the results all together.

Each individual transfer function can only represent a single exp(), not a sum of exp()

[Walter Roberson]

ss (state space) blocks can handle everything in one block.

[Paul]

Neither the Transfer Fcn nor the State Space block can model an Input Delay (nor Output Delay) as far as I can tell.

[Walter Roberson]

You are right, @Paul -- that is a difference between the Simulink blocks and the MATLAB functions.

Answer 3

[Paul]

In addition to using a single transfer function along with gains and transport delays as suggested by @Sam Chak, if you have the Control SystemToolbox, you can use one LTI System block and enter the transfer function as the LTI system variable parameter. For example, if

H(s) = 1/(s +1)*(exp(-1*s) - exp(-0.5*s))

then the expression for the block parameter would be:

tf(1,[1 1])*( exp(-1*tf('s')) - exp(-0.5*tf('s')) )