Analysis of various switch faults of the Three level Neutral point clamped inverter feeding induction motor drive

Multilevel inverters (MLI) are extensively used in various fields. Among the different multi level inverters Three-level neutral-point-clamped (NPC) inverter has been widely applied in power conversions at medium and high voltages. Its usage has been increasing in low-voltage low-power applications. The three-level inverters have the problems due to faulty switches. The effects on the system for short circuited switches are more severe than the open circuited switches if no protective action is taken in time. The proposed analysis of different fault conditions will be helpful in designing algorithm for the mitigation of faults. The various faults such as Diode open, Diode short, Gate open, Gate short, Switch open and Switch short are analysed. The effect of faulty switches on the performance of the Induction motor has been studied through simulations using Matlab/Simulink software.