Electromagnetic compatibility of high power STATCOM in asymmetrical conditions

The article is concerned with the study of electromagnetic compatibility of high power STATCOM when it operates in the mode of feed voltage unbalance. In order to analyze the electromagnetic compatibility conditions of STATCOM in an unbalanced supply network a mathematical model of STATCOM power circuit was developed. The model represents a twelve-pulse transformer winding circuit and the switching angles of the three layer inverter are calculated using the pulse-width modulation method where the selected harmonics are eliminated. In order to improve the harmonic composition of the converter current power circuit contains interphase transformers. The system of inverter control impulses generation was described. The described solutions and algorithms were implemented using the method for structural modeling of Simulink package in Matlab environment. The research work resulted in obtaining the values of total harmonic distortion (THD) of the line current under the influence of various unbalanced voltage drops.