A study of circulating current in MMC based HVDC system under an unbalanced grid condition

Author

Won-Seok Do ; Si-Hwan Kim ; Tae-Jin Kim ; Rae-Young Kim

Author_Institution

Dept. of Electr. & Biomedicai Eng., Hanyang Univ., Seoul, South Korea

fYear

2014

Firstpage

4146

Lastpage

4152

Abstract

This paper shows a study about circulating current of modular multilevel converter (MMC) based a high voltage direct current (HVDC) system under some unbalanced grid conditions. A basic structure of the MMC HVDC system is introduced and its system dynamics is analyzed. Based on the analysis, the modeling of circulating current and its control method under balanced or unbalanced grid condition are described. From the point of view in circulating current control, two kinds of power control methods are analyzed and their performances compared. In addition, in order to apply the power control methods, some practical considerations are proposed and described. Several simulation results performed in the PSIM software verify the proposed analysis and consideration of the power control methods under various grid conditions.

Keywords

HVDC power convertors; electric current control; power control; power grids; MMC HVDC system; PSIM software; circulating current control; high voltage direct current system; modular multilevel converter; power control methods; system dynamics; unbalanced grid conditions; Control systems; HVDC transmission; Inductors; Power control; Power system reliability; Reactive power; Reliability; High Voltage Direct Current (HVDC); Modular Multilevel Converter (MMC); circulating current;

fLanguage

English

Publisher

ieee

Conference_Titel

Industrial Electronics Society, IECON 2014 - 40th Annual Conference of the IEEE

Type

conf

DOI

10.1109/IECON.2014.7049125

Filename

7049125