*Article* **Performance Improvement of Grid-Connected Induction Motors through an Auxiliary Winding Set**

**Luigi Danilo Tornello 1, Salvatore Foti 2, Mario Cacciato 1,\*, Antonio Testa 2, Giacomo Scelba 1, Salvatore De Caro 2, Giuseppe Scarcella <sup>1</sup> and Santi Agatino Rizzo <sup>1</sup>**


**Abstract:** A technique to improve the performance of grid-connected induction motors by exploiting an auxiliary winding set is proposed in this paper. This auxiliary winding features the same distribution of the main winding, although with a reduced number of turns and it is fed by an inverter a fraction of the power in comparison with the rated size of the induction motor. As shown in the paper, through the auxiliary winding, it is possible to set the machine power factor, increasing the efficiency of the power conversion system and mitigating speed oscillations due to torque disturbances. A mitigation of the grid current peaks due to motor start-up is obtainable. First, the proposed technique is theoretically introduced, then a feasibility assessment is accomplished by simulations.

**Keywords:** power factor correction; efficiency; induction machines; pulse width modulation inverters; dual stator winding machines; harmonic compensation
