Model Predictive-Based Fault-Tolerant and Power Balancing Control for Cascaded H-Bridge Inverter

This article presents a fault-tolerant control method combined with a novel power balancing approach based on model predictive control for a three-phase cascaded H-bridge inverter. The fault-tolerant control uses redundant voltage vectors and combination voltages to redistribute the output voltage under switch open-fault and short-fault conditions. To overcome the output power imbalance problem of the conventional fault-tolerant control strategy, inter- and inner-phase power balancing approaches are proposed based on novel reward functions. The effects of H-bridge cell faults on the inverter are analyzed in detail, followed by the operational principles of the proposed power balancing and fault-tolerant control methods. Hardware-based experimental results validate the effectiveness of the proposed strategy.