Modeling and parameter identification of a double-star induction machines

This article deals with the modeling of distributed stator windings of a double-star induction machine (DSIM) and its application to obtain their parameters from no-load and blocked rotor tests. The squirrel cage rotor is modeled as multiphase concentrated windings without electrical connections between them, and the effect of the number of rotor bars on the value of inductances is also addressed. From the equations in the natural reference frame (abc-xyz coordinates), the models in the stationary and synchronous reference frame (α-β1, 3, 5 and d-q1, 3, 5 coordinates) are derived in order to achieve the equivalent circuit at the steady state operation and the parameters are obtained by a standard no-load and blocked rotor test. Finally, the model of the DSIM in the natural reference frame is validated by simulations and verified by experimental tests.