TY - JOUR
T1 - Enhanced independent pole control of hybrid MMC-HVDC system
AU - Xiang, Wang
AU - Ling, Weixing
AU - Xu, Lie
AU - Wen, Jingyu
N1 - © 2017 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this material for advertising or promotional purposes, creating new collective works for resale or redistribution to servers or lists, or reuse of any copyrighted components of this work in other works.
PY - 2018/4/30
Y1 - 2018/4/30
N2 - This paper presents an enhanced independent pole control scheme for hybrid modular multilevel converter (MMC) based on full bridge sub-module (FBSM) and half bridge sub-module (HBSM). A detailed analysis of power distribution between upper and lower arms under asymmetrical DC pole voltages is presented. It is found that the fundamental AC currents in the upper and lower arms are asymmetrical. To enable operation under asymmetrical DC pole voltages, an enhanced independent pole control scheme is proposed. The controller is composed of two DC control loops, two AC control loops and circulating current suppression control based on current injection. Six modulation indices are presented to independently control the upper and lower arms. With this controller, the DC voltage operating region is significantly extended. To ride through pole to ground DC fault without bringing DC bias at the neutral point of interface transformer, a pole to ground DC fault ride through strategy is proposed. Feasibility and effectiveness of the proposed control scheme are verified by simulation results using PSCAD/EMTDC.
AB - This paper presents an enhanced independent pole control scheme for hybrid modular multilevel converter (MMC) based on full bridge sub-module (FBSM) and half bridge sub-module (HBSM). A detailed analysis of power distribution between upper and lower arms under asymmetrical DC pole voltages is presented. It is found that the fundamental AC currents in the upper and lower arms are asymmetrical. To enable operation under asymmetrical DC pole voltages, an enhanced independent pole control scheme is proposed. The controller is composed of two DC control loops, two AC control loops and circulating current suppression control based on current injection. Six modulation indices are presented to independently control the upper and lower arms. With this controller, the DC voltage operating region is significantly extended. To ride through pole to ground DC fault without bringing DC bias at the neutral point of interface transformer, a pole to ground DC fault ride through strategy is proposed. Feasibility and effectiveness of the proposed control scheme are verified by simulation results using PSCAD/EMTDC.
KW - asymmetrical DC pole voltage
KW - DC pole to ground fault
KW - DC pole to pole fault
KW - energy balance
KW - hybrid MMC
KW - overhead line
KW - pole control scheme
KW - modular multilevel converter
KW - full bridge sub-module
KW - half bridge sub-module
UR - http://ieeexplore.ieee.org/xpl/RecentIssue.jsp?punumber=61
U2 - 10.1109/TPWRD.2017.2715040
DO - 10.1109/TPWRD.2017.2715040
M3 - Article
SN - 0885-8977
VL - 33
SP - 861
EP - 872
JO - IEEE Transactions on Power Delivery
JF - IEEE Transactions on Power Delivery
IS - 2
ER -