Title :
AC circulating currents suppression in modular multilevel converter
Author :
She, Xu ; Huang, Alex ; Ni, Xijun ; Burgos, Rolando
Author_Institution :
FREEDM Syst. Center, North Carolina State Univ., Raleigh, NC, USA
Abstract :
Modular multilevel converter is a next generation multilevel converters for medium to high voltage conversion applications, such as medium voltage motor drive and high voltage direct current transmission. One potential issue of this type of converter is the AC circulating current, which increases the current stress and brings additional conduction loss to the system. This paper proposes modified control architecture for modular multilevel converters, aiming at suppressing the AC components in the circulating current. Specifically, a proportional-resonant type minor loop is incorporated to regulate the most AC components of the circulating current to zero in addition to the DC regulation loop. The proposed minor loop can also be applied to single phase MMC, which is not available in previous methods. Simulation results for a three-phase MMC operating as an inverter are provided to demonstrate the feasibility of the proposed method.
Keywords :
HVDC power transmission; electric current; invertors; machine control; power convertors; AC circulating current converter; AC circulating currents suppression; AC components suppression; DC regulation loop; conduction loss; current circulation; current stress; high voltage conversion applications; inverter; medium voltage conversion applications; modified control architecture; modular multilevel converter; most AC components; next generation multilevel converters; proportional-resonant type minor loop; single phase MMC; three-phase MMC operation; Pulse width modulation; Circulating Current; Modular Multilevel Converter; Proportional Resonant Controller;
Conference_Titel :
IECON 2012 - 38th Annual Conference on IEEE Industrial Electronics Society
Conference_Location :
Montreal, QC
Print_ISBN :
978-1-4673-2419-9
Electronic_ISBN :
1553-572X
DOI :
10.1109/IECON.2012.6388809