Crosstalk Analysis and Suppression of Silicon Carbide MOSFET based Three-level Neutral-Point-Clamped Inverter

This paper analyzes the gate-source characteristic of Silicon Carbide (SiC) MOSFET in Three-level Neutral-Point Clamped (3L-NPC) Inverter. To analyze the switching process of the SiC MOSFET, the bridge arm crosstalk and gate voltage oscillation phenomenon of the 3L-NPC, the mathematical model of the cross-talk voltage based on 3L-NPC is introduced. The switching period of the SiC devices is analyzed which include the crosstalk and parasitic oscillation. According to this, the snubber circuit and the gate voltage surge suppression circuit are designed, which also include overcurrent and overvoltage protection. The experiment shows good results of the proposed analyzes. And the conclusion can be extended to multilevel Inverter.