Individual DC Voltage Balance Control for Cascaded H-Bridge Electronic Power Transformer With Separated DC-Link Topology
In this paper, an overall individual dc voltage (including high-voltage and low-voltage dc-link voltages) balance strategy is proposed for the electronic power transformer with separated dc-link topology. The strategy adjusts active powers flowing through the isolation and output stages in different power modules to enhance the dc voltage balance capability. Through the strategy, the high-voltage and low-voltage dc-links can be well balanced when unbalance occurs among different power modules