37 lines
1.0 KiB
Markdown
37 lines
1.0 KiB
Markdown
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title = "Fractional Order Transfer Functions"
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author = ["Thomas Dehaeze"]
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draft = false
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Tags
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:
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## Example Using the FOMCON toolbox {#example-using-the-fomcon-toolbox}
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The documentation for the toolbox is accessible [here](https://fomcon.net/fomcon-toolbox/overview/).
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Here are the parameters that are used to define the wanted properties of the fractional model:
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```matlab
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wb = 2*pi*0.1; % Lowest frequency bound
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wh = 2*pi*1e3; % Highest frequency bound
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n = 8; % Approximation order
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r = 0.5; % Wanted slope, The corresponding phase will be pi*r
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```
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Then, to create an approximation of a fractional-order operator \\(s^r\\) of order \\(n\\) which is valid in the frequency range \\([\omega\_b\, \omega\_h]\\), the `oustafod` function can be used:
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```matlab
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G = oustafod(r,n,wb,wh);
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```
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Few examples of different slopes are shown in Figure [1](#orgb7e7209).
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<a id="orgb7e7209"></a>
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{{< figure src="/ox-hugo/approximate_deriv_int.png" caption="Figure 1: Example of fractional approximations" >}}
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<./biblio/references.bib>
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