Modulated Model Predictive Control for Single-Phase 2-Level Shunt Active Power Filter

Abstract

In conventional model predictive control (MPC) for single-phase 2-level shunt active power filter (SP-2L-SAPF), the voltage vector (VV) that will be applied at the next control cycle is selected by the evaluation of a cost function. However, the application of a single VV, either an active VV (AVV) or a zero VV (ZVV) during the whole control cycle results in a grid current with relatively high ripple. Furthermore, for proper implementation, very fast signal processing is required, which increases cost. Therefore, to overcome these drawbacks, a Modulated MPC (M <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> PC) scheme that uses two VVs in each control cycle is introduced. The improved control scheme predicts the current slopes of the all available VVs, then the algorithm calculates the optimal duty-cycle of the AVVs. After that, the selection of the appropriate AVV is carried out by evaluating and minimizing the cost function as performed in the conventional MPC. Simulated results of the developed M <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> PC algorithm show a better performance and lower THD than those obtained with the conventional MPC for SP-2L-SAPFs.