Re: Simulink:Frequency based parameter change

Devdatt Lad <Devdatt.Lad@xxxxxxxxxxxxx> wrote in message
<g3effu$58i$1@xxxxxxxxxxxxxxxxxx>...
Fatin H wrote:
I have data on a parameter for an element that varies
with
the frequency of the signal. I just have frequency vs.
parameter value in a table. I want to use this
information
to vary a parameter on an element based on the signal
frequency.

I tried creating an approximate Bode plot, but the
magnitudes vary with frequency small enough that making
the
equivalent Bode would take a long time.

Is there a way I can resolve this (table or no table)?

Example Scenario: Capacitance varies with frequency on
a
capacitor. Therefore, 1/C changes.

Which "element" and which "parameter" in Simulink are you
referring to?
Depending on that information, there may be a way.

Check out Simulink's Look Up Tables library. There are
several look up
tables available that you can use.

Devdatt

--
Devdatt Lad
The MathWorks, Inc.

Hi,
Thanks for the response. Basically, I'm trying to simulate
an Ultracapacitor. The model has capacitors and resistors,
but for simplicity, let the model be a series capacitor and
resistor. Both the capacitance and resistance vary with
respect to frequency. I was originally trying to use a
regular transfer function (without use of any other
toolboxes). I thought of using lookup tables, but how would
you take in frequency as an input?

.

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