Conference Paper

Analysis of DC-Link capacitor losses in three-level neutral point clamped and cascaded H-Bridge voltage source inverters

Univ. of Southampton, Southampton, UK
DOI: 10.1109/ISIE.2010.5637820 Conference: Industrial Electronics (ISIE), 2010 IEEE International Symposium on
Source: IEEE Xplore


Loss estimation is a critical aspect of inverter design. The present work investigates the losses occurring in the DC-link capacitors of the three-phase three-level Neutral Point Clamped and Cascaded H-Bridge inverter topologies, by performing a harmonic analysis of the capacitor currents. Results are verified by simulations. Their analysis reveals the advantage of the NPC inverter.

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Available from: Suleiman Sharkh, Apr 13, 2015
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    • ", [16], transistors in Fig. 4 connected to the output nodes (V LX(A,B) ) are fast-switching devices, whereas switches connected to the DC-link V DD , V MID and GND voltages are the slow-switching devices. Idealized switched-mode simulation of the DC/AC inverter from Fig. 4 is shown in Fig. 5. Here, we can see that during the first half-period Φ = H, the output voltage Fig. 5 "
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