Analysis on Grounding Mode of Multi-Terminal VSC-DC Distribution System Based on Hybrid Converters
Compared with Two-Level or Three-Level Voltage Source Converters (VSCs), the modular multi-level converter(MMC) has advantages, such aseasy expansibility, low harmonic distortion and low switching loss.Nevertheless, high initial cost and sophisticated control method also limit the application of MMC.Therefore, Hybrid mode, which combines MMC and conventional VSC, has distinct advantages in practice.This paper focuses on different grounding mode in multi-terminal hybrid converter system,and mainly discusses its influence on the fault characteristics,line protection and fault location of DC distribution system,based on the project of Shenzhen multi-terminal VSC-DC distribution network.By establishing an electromagnetic transient model in PSCAD/EMTDC, the AC side and inner converter single-phase to ground fault, DC line pole to ground fault have been simulated and thoroughly investigated.The simulation result demonstrates that, the DYn connection sets and high resistance grounding mode at the secondary side of the converter-transformer, and the DC capacitor neutral point of conventional VSC through a modest resistance grounding mode, is feasible for better transient performance.
DC distribution system Grounding mode Multi-terminal Modular multilevel converter (MMC) Voltage source converters (VSC)
Gang Sun Bonian Shi Yuming Zhao
国际会议
南京
英文
441-448
2015-09-21（万方平台首次上网日期，不代表论文的发表时间）