Voltage stress on power switches in active NPC topologies

Neutral-Point-Clamped topologies have been widely applied to improve power conversion efficiency. Active NPC variants may offer an advantage in terms of efficiency and losses distribution. Remarkably, Active NPC topologies differ from traditional NPC in terms of power semiconductors characteristics and commutation paths. This paper investigates Active 3L NPC converters in double-conversion UPS applications. Particularly, it discusses voltage stress on power switches in Active NPC converters, presenting experimental results from high-power 3ph UPS implementation.