Effective Switch Fault Detection and Classification in Seven-Level Switched capacitor Multilevel Inverter by Using Variable Mode decomposition

Multilevel inverters (MLIs) are commonly used in industry for various medium and high power applications. However, as the number of switches in an MLI increases, the possibility of faults increases. Ensuring the reliability of MLIs is a critical concern, making effective fault detection and localization methods essential. This paper presents a new method for quickly identifying and locating open switch faults (OCFs) in a single-phase seven-level switched capacitor multilevel inverter (7L-SCMLI), which can triple the voltage output. The method focuses on analyzing the faulty voltage signal produced by the inverter, which contains important information about its operation. To extract useful information from this voltage signal, use a signal processing technique called Variable Mode Decomposition (VMD). VMD breaks the voltage signal into different modes, each highlighting a specific component of the signal. These components are then transformed into singular values to create an analytic signal. This analytic signal helps set a threshold for detecting faults and identifying the faulty switch. Moreover the paper includes detailed analysis and simulation results to validate the effectiveness of this method for the 7L-SCMLI.