Short Circuit and Open Circuit Fault Identification Strategy for 3-Level Neutral Point Clamped Inverter

Industrial drives have various applications to control speed, torque, frequency in industrial motors. The core of such a driving system is the power electronics converter. The three-level neutral point clamped (NPC) converter has a variety of applications in medium voltage inverter drive systems due to advantages such as better power quality, reduced cost, and increased efficiency. In general, the power converters are more vulnerable to power quality events. To enhance the NPC's reliability, various strategies are adapted, especially on critical applications. The focus of this research is to identify faulty switches to improve the reliability of a three-level NPC converter. An open circuit and short circuit fault detection technique for three-level three-phase NPC converters is established in this article. The proposed fault detection strategy for the NPC inverter is simulated in Matlab/Simulink, and the test results are presented in-depth. The novelty of the project lies within the experimental study of the system, which can diagnose both short-circuit and open-circuit faults occurring in the inverter.