Comparison of Different Modulation Techniques in Single Phase Modular Multilevel Converter

The concept of modular multilevel converter is to achieve high power semiconductor switches with several lower voltage dc sources to perform the power conversion. Voltage levels in modular multilevel converter are used in High voltage applications and electric drives. The project focuses on the comparison of modulation techniques in single phase modular multilevel converter. The carrier based modulation technique is compared with staircase modulation technique. Level shift carrier based modulation technique is used for comparison with staircase modulation technique. The performance of both modulation techniques is compared by total harmonic distortion in MATLAB/SIMULINK. Simulation results for modular multilevel converter are done with seven sub modules in upper arm and lower arm. The level shift modulation technique has lesser percentage of total harmonic distortion.