Energy Storage Systems Current Ripple Reduction for DC-Link Balancing Method in Hybrid CHB Topology

Abstract

This paper focusses on a hybrid topology for a CHB, where some or the modules are equipped with energy storage systems. In addition to the well-known capabilities of the CHB as a STATCOM, the hybrid topology has new advantages as a grid stabilizer. However, the current ripple on the energy storage systems has negative effects which tends to result in expensive solutions. To overcome this inconvenient, a previously known balance strategy is modified to prevent the ripple without compromising the DC-Link balance. This new control method is demonstrated through simulations.