Finite Control Set Model Predictive Torque Control of Induction Motors using a Neutral Point Clamped Three-Level Inverter with Computational load Reduction

In this paper, a FCS-MPC strategy for the torque control of 3 phase induction motors using a NPC type 3-level inverter is proposed. It derives a reference state for the given torque reference. Use of a performance index penalizing tracking error for the reference state. Here we propose to confine the evaluation of the performance index to 3 voltage vectors of the 3-level inverter considering the fact that the dynamics of the electrical system is far faster than that of mechanical system. Thus the computational load is not increased compared to earlier FCS-MPC methods based on 2-level inverters. An effective method to maintain the balance of dc capacitors is also proposed. The efficacy of the proposed method is proved simulations.