Three-Level Active Neutral-Point-Clamped (ANPC) Converter with Fault Tolerant Ability

Compared with traditional three-level neutral-point-clamped converter, the recently proposed three-level active neutral-point-clamped (ANPC) converter can overcome the unequal loss distribution among semiconductor devices, and therefore result in increased output power or switching frequency. In industrial applications, fault tolerance of power electronics converters is very important considering system availability, safety and reliability. This paper presents the fault tolerant ability of three-level ANPC converter. Control schemes are proposed to keep the neutral-point voltage balanced and get stable and continuous output under single device fault for both open-circuit fault and short-circuit fault cases. Simulation results show the effectiveness of the fault tolerant ability of the three-level ANPC inverter under the presented control strategies, which are promising to carry on further experimental validation.