Mario Gommeringer, Felix Kammerer, Johannes Kolb, Michael Braun

PCIM Europe 2013, Nürnberg

This paper presents a novel DC-AC converter circuit, especially for the application in multilevel battery energy storage systems (BESS). A drawback of the commonly used cas caded H-bridge is that the RMS values of the battery currents can reach multiples of the mean DC battery currents. Additional DC-DC converters in the cells can reduce the AC components of the battery currents, but cause  additional semiconductor losses and require large inductors. The circuit presented in this paper reduces these AC contents with less semiconductor losses and smaller inductors than standard DC-DC converters connected to H-bridges.