REVIEW OF CIRCULATING CURRENT CONTROL METHODS IN MODULAR MULTILEVEL CONVERTER
Publication Date : 30/12/2020
An equally challenging issue with modular multilevel converter (MMC) is the circulating current which usually flows through the arms of the converter and distorts the arms currents by introducing second order harmonics, add extra losses to the converter and impacts its components ratings and amplitude of the capacitor voltage ripples. It is as a result of the variation in the instantaneous voltages among the three phases of the converter that arise from the voltage variation in the DC capacitor voltages. Circulating current needs to be properly controlled in order to improve the performance of the converter. This paper reviewed the methods of controlling the AC part of the circulating current which is responsible for the double-line frequency component in the arm currents of MMC.
No. of Downloads :