Control of modular multilevel converter as input side of a smart transformer

This work is based in the cascade connection of several H-bridges as input side of a multiport smart transformer. This paper is focused on finding the best control strategy for this stage, turning from previous individual controllers to a centralized control. This control strategy must guarantee a stable voltage in the DC bus of the desired value, and achieve a unity power factor. In addition, it has been solved another problem derived from applying the control strategy, that was a distortion in the input current caused by a third harmonic component.