Variable-structure direct torque control for induction motor driven by a matrix converter with overmodulation strategy

In this paper, an improved torque control method for induction motor driven by a matrix converter is presented, in which the principles of variable-structure(VS) control and direct torque control (DTC) are combined to ensure high-performance operation in the steady state and under transient conditions. Two hysteresis regulators or the existing proportional-integral controllers of torque and flux were substituted by the variable structure controller respectively, which preserve the fast responses and robustness merits of conventional DTC for induction motor driven by matrix converter. To improve the dynamic torque response of proposed strategy, an overmodulation strategy is also presented. The performances of the proposed strategy are verified in simulation.