Fault-Tolerant Operation Analysis of a Five-Phase Three-Level TNPC Inverter for Electric Aircraft Propulsion Systems

Abstract:
This paper presents an analysis of a five-phase three-level TNPC inverter focusing on its fault-tolerant capabilities and mitigation techniques for electric aircraft propulsion systems. The space vector pulsewidth- modulation (SVPWM) schemes in both normal and post-fault operations accounting for short-circuit and open-circuit occurrences in individual power electronic switches in a single phase are discussed. In fault cases, the remaining switching vectors and their sequences are selected to produce the necessary voltage in the alphabeta-coordinate system. This selection aims to efficiently suppress undesired voltage components and complying with the rules focusing on minimizing switching losses. These methods are implemented and assessed through simulation, showing the ability and performance limitations of the inverter under various fault conditions.