Direct Torque Control Based on RST Regulator of a Double Star Induction Machine

Abstract

The paper discusses a direct torque control (DTC) strategy based on a RST regulator for double star induction machine (DSIM). The DTC is an excellent solution for general-purpose induction drives in very wide range The short sampling time required by the DTC schemes makes them suited to a very fast torque and flux controlled drives as well the simplicity of the control algorithm The DSIM is built with two symmetrical 3-phase armature winding systems, electrically shifted by 30. A suitable transformation matrix is used to develop a simple dynamic model in view of control. The analysis of the torque in the stator flux linkage reference frame shows that the concept of DTC can be applied in DSIM. A set of voltage vectors corresponding to the switching mode are chosen to over a maximum voltage and keep the harmonics at a minimum. Further, a switching table specific for DSSM is proposed. Simulations results are given to show the effectiveness and the robustness of our approach.