A New Post-Fault Control Method Based on Sinusoidal Pulse Width Modulation Technique for a Neutral Point Clamped (NPC) Inverter

This paper introduces a new fault-tolerant technique for three-phase three-level inverters based on sinusoidal pulse width modulation (SPWM). The existing fault-tolerant methods mainly depend on using space vector modulation (SVM) to utilize the redundant switching states at low modulation index. The proposed method achieves a fully compensated tolerance at low modulation index but with less complexity in compared to SVM method. Neutral point clamped inverter (NPC) is used to analyze the proposed method performance at different open-switch faults. By changing the modulating signal at fault-tolerant, both phase currents and output line voltage have the values as healthy conditions. Matlab/Simulink is used to verify the proposed method.