Asynchron No States $—$ AC Induction Machine

This component describes the torque of an electrical asynchron machine as a function of slip.

Assumptions

Very simple component assuming sinusoidal symmetrical three-phase supply voltages and steady state torque.

Limitations

The component does not describe the transients while starting or stopping a machine.

 Equations $\mathrm{slip}=1-\frac{w}{{w}_{0}}$ $\mathrm{tau}=\left\{\begin{array}{cc}\frac{2\mathrm{peaktorque}}{\frac{\mathrm{slip}}{\mathrm{pulloutslip}}+\frac{\mathrm{pulloutslip}}{\mathrm{slip}}}& \frac{1}{100000}<\left|\frac{\mathrm{slip}}{\mathrm{pulloutslip}}\right|\\ 0& \mathrm{otherwise}\end{array}\right\$ $w={\mathrm{∂}}_{t}\left(\mathrm{\phi }\right)$ ${\mathrm{φ}}_{a}=\mathrm{\phi }$ ${\mathrm{φ}}_{b}=\mathrm{\phi }$ $-\mathrm{\tau }=\mathrm{flange_a.tau}+\mathrm{flange_b.tau}$

Variables

 Name Value Units Description Modelica ID $\mathrm{slip}$ slip $\mathrm{\tau }$ $Nm$ tau $\mathrm{\phi }$ $\mathrm{rad}$ Rotation angle of component (= flange_a.phi = flange_b.phi) phi $w$ $\frac{\mathrm{rad}}{s}$ Absolute angular velocity of component w

Connections

 Name Description Modelica ID ${\mathrm{flange}}_{a}$ (left) driving flange (flange axis directed INTO cut plane) flange_a ${\mathrm{flange}}_{b}$ (right) driven flange (flange axis directed OUT OF cut plane) flange_b

Parameters

 Name Default Units Description Modelica ID ${w}_{0}$ $157.08$ $\frac{\mathrm{rad}}{s}$ Angular frequency w0 pullout slip $0.15$ Pull-out slip pulloutslip $\mathrm{peaktorque}$ $300$ $Nm$ Peak torque peaktorque