A Multilevel Cascaded Converter for a Battery Energy Storage System

This paper describes the analysis and design of a single-phase multilevel cascaded H-bridge (CHB) converter for battery energy storage. Furthermore, it studies the second-order harmonic currents and voltages associated with single-phase converters which are transferred from the ac power side to the dc side. The conventional strategy used to reduce ripple current involves bulky dc-link capacitors connected in parallel with the dc bus for ripple reduction. An active filtering strategy is proposed to minimize the energy storage requirements.