CAJ | 학술논문

针对一种整流侧采用电网换相换流器(line commutated converter，LCC)、逆变侧采用LCC与模块化多电平换流器(modular multilevel converter，MMC)串联的混合直流输电拓扑结构进行研究，建立混合直流输电系统模型，推导稳态数学模型，设计系统协调控制策略，并分析其穿越直流故障的机理。在PSCAD/EMTDC仿真环境下搭建混合直流输电的模型，对系统的启动、稳态、交流故障及直流故障穿越特性进行研究。仿真结果表明：系统具有良好的启动和稳态特性； MMC可改善逆变侧交流系统电压稳定性，降低换相失败发生的概率；系统具有直流故障穿越与快速恢复的特性，适用于架空线路输电的场合。
침대일충정류측채용전망환상환류기(line commutated converter，LCC)、역변측채용LCC여모괴화다전평환류기(modular multilevel converter，MMC)천련적혼합직류수전탁복결구진행연구，건립혼합직류수전계통모형，추도은태수학모형，설계계통협조공제책략，병분석기천월직류고장적궤리。재PSCAD/EMTDC방진배경하탑건혼합직류수전적모형，대계통적계동、은태、교류고장급직류고장천월특성진행연구。방진결과표명：계통구유량호적계동화은태특성； MMC가개선역변측교류계통전압은정성，강저환상실패발생적개솔；계통구유직류고장천월여쾌속회복적특성，괄용우가공선로수전적장합。
This paper investigated a hybrid high voltage direct current (HVDC) system, in which the rectifier adopts line commutated converter (LCC) and the inverter was composed by LCC in series with the modular multilevel converter (MMC). The model of this hybrid HVDC system was developed, steady-state mathematical model was deduced, the coordinated control strategy was designed, and the DC fault ride-through capability was analyzed in this paper. The hybrid HVDC system was built in the PSCAD/EMTDC simulation environment. Simulation results show that the hybrid HVDC system possesses favorable start-up and steady performances, the risk of commutation failure is reduced due to the effective regulation of inverter AC busbar voltage by MMC, and the hybrid HVDC system possesses the DC fault ride-through and quick recovery capability, which can be applied for the overhead line transmission.