Universal control scheme for power electronics building-block-based cascaded multilevel inverters

In the field of high-power medium-voltage applications, multilevel inverter technology has become a very interesting alternative. The strengths of the multilevel technology include for instance utilization of low-voltage power semiconductors and low-distortion output voltage compared with two-level designs. A building-block-based approach is suitable especially for a cascaded H-bridge circuit topology. Because of a variety of existing control and modulation strategies, the design of building-block-based systems is not straightforward. The design of a building block has an effect on the possible applications and usable control and modulation strategies. In this paper, the problematic nature of functionality allocation in power electronics building-block-based systems is discussed. A distributed communication and synchronization scheme for PEBB-based systems is discussed in brief. A universal control scheme for cascaded H-bridge multilevel inverters is proposed. The control scheme enables the use of H-bridge-based building blocks with a variety of modulation strategies.