Reduced Switching-Frequency Modulation Design for Model Predictive Control Based Modular Multilevel Converters
arXiv:1912.08433
Abstract
This paper proposes a novel switching algorithm for modular multilevel converters (MMCs) that significantly reduces the switching frequency while fulfilling all control objectives required for their proper operation. Unlike in the conventional capacitor voltage-balancing strategies, in addition to submodule (SM) capacitor voltages, the proposed algorithm considers previous switching statuses during sorting. The algorithm is applied to a seven-level back-to-back MMC-HVDC system and tested under various operating conditions. Significant reduction in the switching frequency with trivial impacts on submodule capacitor voltages are observed.
Accepted and presented to the 2019 IEEE 2nd International Conference on Renewable Energy and Power Engineering