Fault tolerant operation of active neutral point clamped multilevel converters using a voltage sliding mode controller

The three-level active neutral point clamped converter (ANPC) allows to overcame the problem of unequal loss distribution among semiconductor devices that appears in the classical neutral point clamped converter NPC. Another advantage of this power converter is that it can operate under faulty conditions. In this paper the study of the ANPC using a voltage sliding mode controller for a vector modulator under a semiconductor open fault is presented. The approach allows keeping the voltage of the neutral point balanced under a fault condition. Simulation results are presented in order to verify the effectiveness of the proposed control strategy under the fault condition mode.