Need to find a transfer function by hand and plot using Matlab

WilkinsMicawber

Joined Jun 5, 2017
29
The calculation of the transfer function for (the voltage across L1 and C1)/ Vin for the circuit below resulted in results that I am having a hard time converting to S form for matlab. S = jw, and S^2 = j^2w^2, but i'm getting results with w in the denominator or single w's with j^2. Are there any special procedures for converting to a form matlab can plot?

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WilkinsMicawber

Joined Jun 5, 2017
29
I found the solution. Take the magnitude of the imaginary and real parts by squaring each and adding them together under a square root. Plot the magnitude for different values of w.

RBR1317

Joined Nov 13, 2010
522
I'm a user of Maple rather than MATLAB; Maple has a Bode plot function that accepts a system transfer function so that one can avoid doing magnitude & phase calculations. Just focus on getting the transfer function. A view of the Maple worksheet is attached. You might check whether your MATLAB has a similar bode() function.

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MrAl

Joined Jun 17, 2014
7,147
The calculation of the transfer function for (the voltage across L1 and C1)/ Vin for the circuit below resulted in results that I am having a hard time converting to S form for matlab. S = jw, and S^2 = j^2w^2, but i'm getting results with w in the denominator or single w's with j^2. Are there any special procedures for converting to a form matlab can plot?
Hi,

If you do this by hand just use 's' in place of where you would have used "j*w" and that gives you the F(s) form.