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Direct model predictive control (MPC) strategies that achieve long prediction horizons with a modest computational complexity are reviewed in this article, focusing on power electronics applications. In many MPC problems, a long prediction horizon is required to ensure an adequate closed-loop performance in steady state and to avoid stability issues. However, the computational effort of solving the optimization problem underlying MPC problems with long prediction horizons is often very great, making the implementation of such schemes in real time a difficult and challenging task. To overcome this difficulty, three established methodologies are surveyed that yield long prediction horizons with a modest computational burden. Case studies are investigated to substantiate the merits of these schemes. More specifically, for dc?dc boost converters, a move blocking strategy is reviewed, and for ac medium-voltage (MV) drives, both an extrapolation and an event-based horizon strategy are examined. [ABSTRACT FROM PUBLISHER]

In this paper, the recently introduced model predictive pulse pattern control (\MP^3\C) strategy is adapted to the ACS 2000 medium-voltage (MV) drive of ABB. The drive system consists of a five-level active neutral-point-clamped (ANPC-5L) rectifier, an inverter, and an induction machine (IM). The inverter is fed with offline-computed optimized pulse patterns (OPPs) that produce minimum harmonic distortion in the stator windings of the ac machine. An optimal stator flux trajectory is calculated from these OPPs, and a trajectory controller tracks it in real time. In the proposed approach, trajectory tracking is based on model predictive control: a constrained optimal control problem is formulated and solved in real time in a computationally efficient manner. An event-based prediction horizon is employed in order to ensure fast tracking of the stator flux trajectory. The advantages of the proposed method are optimal steady-state behavior in terms of harmonic distortion and fast torque response. The method was tested on an MV ANPC-5L inverter coupled to a general-purpose 1.21-MW IM. Experimental results were obtained from this industrial setup, and they are presented in this paper to demonstrate the high performance of \MP^3\C. [ABSTRACT FROM PUBLISHER]