HAN Wei, YANG Ruizhang, LIU Chao, et al. DC Fault Characteristics and Fault Current Suppression Strategy of Three-terminal Hybrid HVDC System Based on LCC and Hybrid MMC[J]. High voltageapparatus, 2021, 57(6): 179-188.
DOI:
HAN Wei, YANG Ruizhang, LIU Chao, et al. DC Fault Characteristics and Fault Current Suppression Strategy of Three-terminal Hybrid HVDC System Based on LCC and Hybrid MMC[J]. High voltageapparatus, 2021, 57(6): 179-188. DOI: 10.13296/j.1001-1609.hva.2021.06.023.
DC Fault Characteristics and Fault Current Suppression Strategy of Three-terminal Hybrid HVDC System Based on LCC and Hybrid MMC
The DC fault characteristics and the fault identification method of hybrid three-terminal HVDC transmission system and fast suppression strategy of fault current are proposed. The system is composed of a line-commutated converter as the rectifier and two parallel hybrid modular multilevel converters as the inverters. Based on the model in PSCAD/EMTDC
the fault characteristics of pole-to-ground and pole-to-pole of the system at different locations are analyzed. In addition
the mechanism of hybrid MMC fault overcurrent in hybrid three-terminal DC system under DC fault is analyzed
to suppress the excessive fault current in the fault transient
additional control is set to the controller of LCC and MMC. Lastly
the simulation analysis of pole-to-ground fault in different positions of the system is carried out. The simulation results show that the improved control strategy can effectively suppress the fault current produced by the converters.