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Asynchronous machine.
Machines
The library contains two different models for the Induction Machines. Mathematically, both models are identical. They differ only in the way they can be used.
The standard model of the Induction Machine can only be used with the continuous state-space method. The model is based on a three-phase system instead of the usual reference frame. This facilitates the connection of external inductances in series with the stator windings. However, external inductors cannot be connected to the rotor due to the current sources in the model. In this case, external inductors must be included in the leakage inductance of the rotor.
The discretizable model can be used with both the continuous and the discrete state-space method. This model is based on machine equations in the stationary reference frame (Clarke transformation). To facilitate the discretization of the model the Integrator block is used which allows non-linear feedback in the circuit. All external inductors must be included in the leakage inductances.
The machines operates as a motor or generator; the sign of the mechanical torque determines the mode of operation (positive for motoring, negative for generating). All electrical variables and parameters are viewed from the stator side. In the component icon, phase a of the stator and rotor winding is marked with a dot.
Stator and rotor currents transformed into the stationary reference frame:
In the preceding equations,