The Rotational Speed (or Speed) component generates a forced angular speed according to an input signal, $w_{\mathrm{ref}}$

The $\mathrm{Exact}$ boolean parameter determine how $w_{\mathrm{ref}}$ is used:

When $\mathrm{Exact}$ is true, $w_{\mathrm{ref}}$ is used as-is. The input signal must be differentiable.

When $\mathrm{Exact}$ is false (the default), $w_{\mathrm{ref}}$ is filtered and the derivative of the filtered curve is used to compute the reference acceleration of the flange. This derivative is not computed by numerical differentiation but rather by a first-order filter. The critical frequency (cut-off frequency) of the filter is defined by the parameter $f_{\mathrm{crit}}$, which should be higher than the essential low frequencies in the signal.

$\{\begin{array}{cc}\left\{a\=0\,w\=w_{\mathrm{ref}}\right\}& \mathrm{Exact}\\ \left\{a\=\left(w_{\mathrm{ref}}-w\right)w_{\mathrm{crit}}\,a\=\stackrel{\.}{w}\right\}& \mathrm{otherwise}\end{array}$

$w_{\mathrm{crit}}\=2\mathrm{\pi }{f}_{\mathrm{crit}}$

$w\=\stackrel{\.}{\mathrm{\phi }}$

$\mathbf{if}\mathrm{Use\; Support\; Flange}\mathbf{then}{\mathrm{\tau }}_{\mathrm{support}}\=-\mathrm{\tau }$

$\mathrm{\phi }\={\mathrm{\phi }}_{\mathrm{flange}}-\{\begin{array}{cc}{\mathrm{\phi }}_{\mathrm{support}}& \mathrm{Use\; Support}\\ 0& \mathrm{otherwise}\end{array}$

The component described in this topic is from the Modelica Standard Library. To view the original documentation, which includes author and copyright information, click here.