Mobile QR Code QR CODE : The Korean Institute of Power Electronics
Title THD Analysis of Output Voltage According to PWM Carriers in Single-Delta Bridge Cell MMC
Authors Jae-Myeong Kim ; Jae-Jung Jung
Page pp.526-534
ISSN 1229-2214
Keywords Carrier wave; Full-bridge cell; MMC(Modular Multilevel Converter); PSPWM(Phase-Shifted Pulse Width Modulation); THD(Total Harmonic Distortion)
Abstract The modular multilevel converter (MMC) has been widely applied to various industrial areas because of its
various advantages and structural characteristics. Therefore, many methods for synthesizing the output voltage
of MMC have been studied. Among these methods, phase-shifted pulse width modulation (PSPWM) is
frequently used in MMC systems because it has diverse merits, such as excellent output qualities even with a
small number of cells and uniform power distribution among cells. In this study, the total harmonic distortion
(THD) of the output voltage is analyzed in accordance with the number of cells in one arm of a single-delta
bridge cell MMC in order to compare PSPWM methods in terms of the THD of the output voltage. The
physical characteristics of the triangle and sawtooth carrier waves used for the PSPWM and the mathematical
modeling of output voltage are introduced. Then, the obtained results are verified through real-time simulation
of a 1 MW single-delta bridge cell MMC system