Predictive torque control of an induction machine fed by a neutral point clamped inverter

This paper presents a model predictive control strategy for an induction machine fed by a three-level neutral point clamped inverter. Two different voltage balancing algorithms are compared: The first one is hysteresis-based, the second algorithm is weighting factor-based, i. e. the DC link capacitor voltage unbalance is evaluated directly within the cost function. The proposed control algorithms are verified by several simulations which clearly verify that an effective control of speed, torque, flux and of the DC link capacitor voltages is possible.