Method for controlling sub-module levels of Modular Multilevel Converter for fluctuations reduction of power grid frequency

摘要

The present invention relates to a control method of the output level of the MMC converter for reducing the system frequency variation to adjust the output level of the MMC converter in response to the system frequency variation of the power system in the MMC converter associated with the power system. An output level control method of an MMC converter according to the present invention includes a detection step of detecting a system frequency of a system linked to an MMC converter in real time, a comparison step of comparing the detected system frequency with a preset reference system frequency, and the detection. And adjusting the number of output levels of the MMC converter in a direction of reducing a difference between the system frequency and the reference system frequency when the system frequency is different from the reference system frequency.