In this paper, direct torque control (DTC) applied to a double star induction motor (DSIM) is studied when one or several phases are lost. To this aim, a general decoupled model of the induction machine fed by two three parallel voltage source inverters (VSI) with up to three open phases is given. Then, using a proposed control scheme, the pulsating of the torque is reduced and the drive performance improved without synthesizing a set of optimal current waveforms as the existing techniques do. Numerical simulations and experimental results are carried out to highlight the effectiveness of the proposed control scheme.

Keywords: Double star induction motor (DSIM), Direct torque control (DTC), Voltage source inverter (VSI)