Application of modular multilevel converter for HVDC transmission with selective harmonics

The modular multilevel converter (MMC) is based on the cascaded interconnection of half-bridge switching sub-modules. It features modular characteristics that allow its expandability while providing high quality voltage and current output waveforms and removing the need for bulky passive filters. This paper proposes a control technique and two modulation techniques for the modular multilevel converter. For the first time a multiple cuts ellipsoidal algorithm is used in order to find the switching angles for the selective harmonic elimination (SHE PWM).