Comparison between T-cell and half-bridge cell submodule based modular multilevel converters for use in smart transformer

Modular Multilevel Converter (MMC) system has many advantages over conventional voltage source converters and therefore they can play major role in Direct Current power transmission, micro grid, or renewable energy applications and recently it attracted attention to use in smart transformers. MMC’s distinctive topology offers many new features, it also offer a sophisticated topology to deal with high frequency requirements of generating a sinusoidal voltage waveform for smart transformers. In this work we will make a comparison between T-cell Submodule based MMC and Half-Bridge Submodule based MMC when generating 1kHz voltage waveform as we will investigate capacitor voltages, AC voltage and current THD as generating high frequency sinusoidal voltage waveform is essential for the size of Smart Transformers. Simulation analysis has been done using MATLAB/Simulink and the results are verified.