Submodule Capacitor Voltage Ripple Reduction of Full-Bridge Submodule-Based MMC (FBSM-MMC) with Non-Sinusoidal Voltage Injection

The full-bridge submodule (FBSM)-based modular multilevel converter (FBSM-MMC) offers promising performance due to its ability output negative FBSM voltage. This paper studies this of the FBSM-MMC under zero-sequence voltage injection (ZSVI) and second-order harmonic current (SHCI). focus research is redistribute powers by injecting an additional power degree freedom, resulting in a smaller capacitor ripple, while keeping maximum AC for given fundamental frequency component arm reference. Accordingly, control strategy was developed, based on non-sinusoidal ZSVI, SHCI proposed further improving FBSM-MMC. ZSVI contains higher sinusoidal third-order than that pure (THVI) when operating same By implementing solution, amplitude injected can be achieved, producing lower loss Considering relationship voltages are also discussed. Finally, simulation results experimental presented verify effectiveness theoretical analysis method.