Medium voltage motor drives (MVD) come in various topologies that allow designers to choose the best option for their application based on technical and economic considerations. The Neutral Point Clamped (NPC) and Cascade H-Bridge (CHB) are the most particular topologies that have come to the fore. CHB and NPC MVD's primary operating principles, switching stress, topological complexity, and harmonic distortion of the inverter output will be presented in this article, along with a brief review of suitable modules. Even though the number of parts in a cascaded inverter is lower than that of a neutral point-clamped inverter, it has been demonstrated that the stress on the switches in both types of inverters is the same and that the resulting output waveforms are nearly identical in terms of harmonic distortion. The neutral point clamped topology requires less secondary winding from the transformer, fewer voltage-balancing capacitors, the same quantity of switches, and extra clamping diodes. Benefits of NPC include high-power-density inverters, enhanced output quality, reduced number of components, reduced heat losses, increased efficiency, elimination of commonmode voltages and currents thanks to an isolation transformer, and a remote transformer that allows for a more adaptable footprint. Additionally, the NPC drive rectifier system (Transformer and diode H-bridges) has the advantage of more simplicity, ease of assembly, fewer connections, fewer space requirements, and an expensive isolation transformer. The MATLAB simulation for both topologies was carried out, with 3 phase motor 3.8kV, 150 KW motor parameters.
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