Deadbeat Nearest Current Modulation Strategy of MMC-based SAB Converter

To tackle the high harmonic content and losses in traditional step wave modulation for medium voltage DC distribution networks using MMC-based single active bridge (SAB) converters, a deadbeat nearest current modulation (D-NCM) strategy has been proposed. This strategy converts the single-phase system into a two-phase system through virtual orthogonal components and calculates the AC side current reference value using decoupling control. By comparing the measured current with the reference, the number of activated submodules is dynamically adjusted, allowing precise AC side current control. MATLAB/Simulink simulations show that D-NCM effectively reduces harmonic content and minimizes switching losses, enhancing overall system performance. This research suggests that D-NCM is a viable solution for improving electrical energy quality and operational efficiency in medium volt-age DC distribution networks.