Open‐circuit submodule fault diagnosis in MMCs using support vector machines

Series connection of semiconductor submodules (SM) in a modular multilevel converter (MMC) makes the MMC prone to open-circuit (OC) IGBT failures inside SMs. If left undetected, these faults degrade operation and lead its instability. This article proposes method detect, localise, classify single OC SM an using support vector machines (SVM) trained with data obtained from capacitor voltage balancing block control system. The proposed relies on extracted sorted arrays upper lower phase arms. Therefore, it does not require extra measurements hardware. Additionally, offers fixed time for detecting localising faults. is easy implement as SVM has simple decision function. Time-domain simulation case studies are performed three-phase nine-level evaluate performance method.