An Adaptive Weight Model Predictive Control Strategy for Vienna Rectifiers Under Unbalanced Loads

Abstract

This study tackles the challenge of managing midpoint potential imbalance and suppressing current zero-crossing distortion in Vienna rectifiers under conditions of unbalanced load. To address this, an adaptive weight model predictive control strategy is proposed. The research begins by analyzing the interaction between maintaining midpoint potential balance and mitigating current zero-crossing distortion, taking into account influences, such as current ripple, sampling inaccuracies, and load imbalance. A prediction model is formulated to predict the behavior of the voltage vector coupling error. Using this predictive framework, a multiobjective model predictive control strategy is developed, incorporating a weight adaptive optimization technique to enhance the coordination between objectives. Experimental results validate the effectiveness of the proposed approach in controlling neutral-point potential imbalance, reducing current harmonics, and suppressing zero-crossing distortion, demonstrating its advantages over existing methods.