Unified Graph Theory-Based Modeling and Control Methodology of Lattice Converters

Abstract

Lattice converters combine the merits of both cascaded-bridge converters and multi-paralleled converters, leading to infinitely large current and voltage capabilities with modularity and scalability as well as small passive components. However, lattice converters suffer from complexity, which poses a serious threat to their widespread adoption. By use of graph theory, this article proposes a unified modeling and control methodology for various lattice converters, resulting in the satisfaction of their key control objectives, including selected inputs/outputs, desired voltages, current sharing, dynamic voltage balancing, and performance optimization. In addition, this article proposes a plurality of novel lattice converter topologies, which complement state-of-the-art options. Simulation and experimental results verify the effectiveness and superiority of the proposed methodology and lattice converters.

Keywords

• algorithms
• cascaded-bridge converters
• graph theory
• lattice converters
• modular multilevel converters (MMCs)
• multi-paralleled converters