A consensus approach to distributed balancing control of modular multilevel converters

Modular multilevel converters (MMCs) are predominant in novel high and medium power applications, such as renewable energy generation and high-voltage direct-current transmission. This hardware offers better performance than other voltage-source-converters due to its higher efficiency, modular design and lower harmonic content. To achieve the expected results, it is essential to coordinate the actions of all the MMC modules using balancing control methods. Different from the previous solutions, this paper proposes a consensus control approach using a leader-follower topology to solve the balancing control problem for MMCs. The proposed control method guarantees asymptotic convergence of all modules to a consensus state, allows a distributed implementation and increases the robustness against module failures. Simulation results using Matlab show the advantages of the developed method.