The QuasiStatic Stray Load component models the effect of current-dependent torque losses.

Stray load losses are modeled similar to standards EN 60034-2 and IEEE 512, i.e., they are dependent on square of current, but without scaling them to zero at no-load current. The stray load losses are modeled such way that they do not cause a voltage drop in the electric circuit; instead, the losses are dissipated through a braking torque at the shaft.

$\mathrm{\tau }\={\mathrm{\tau }}_{\mathrm{support}}\=-{\mathrm{\tau }}_{\mathrm{flange}}\=-\left(\frac{P_{\mathrm{ref}}}{w_{\mathrm{ref}}}\right){\left(\frac{i_{\mathrm{RMS}}}{I_{\mathrm{ref}}}\right)}^2\{\begin{array}{cc}0& P_{\mathrm{ref}}\le 0\\ \mathrm{sgn}\left(w\right){\left(\frac{\left|w\right|}{w_{\mathrm{ref}}}\right)}^{P_w}& \mathrm{otherwise}\end{array}$

$w\=\frac{d\mathrm{\phi }}{\mathrm{dt}}$

$\mathrm{\phi }\={\mathrm{\phi }}_{\mathrm{flange}}-{\mathrm{\phi }}_{\mathrm{support}}$

$i\=i_p\=-i_n$

$v\=v_p-v_n$

$\mathrm{lossPower}\=-\mathrm{\tau }w$

$\mathrm{\omega }\=\frac{d{\mathrm{\gamma }}_p}{\mathrm{dt}}$

${\mathrm{\gamma }}_p\=\mathrm{\gamma }\+{\mathrm{\gamma }}_n$

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.