Grid power flow impact on the on-state losses of the modular multilevel converter

The efficiency of the Modular Multilevel Converters (MMC) makes it the preferable VSC solution for the HVdc field. The knowledge of its modus operandi and their devices it is extremely important to improve the MMC performance. This work analyzes the on-state mode of the half-bridge cell semiconductors in respect to the active/ reactive power flow conditions of the MMC. The MMC-HVdc INELFE project model was adopted to perform the converter analysis and simulations. It is shown that the lower switch of the half-bridge cell is responsible for the most of the on-state losses of the converter.