摘要
2016年南方电网建成投运了世界首个并联混合直流输电工程——鲁西背靠背直流工程,为了分析其稳态运行及故障恢复特性,基于PSCAD/EMTDC仿真平台,搭建了包含常规直流单元和柔性直流单元的混合直流异步联网系统仿真模型。依托鲁西背靠背工程,分别建立常规直流单元和柔性直流单元的主回路和控制系统模型,并联形成混合直流异步联网系统并对所搭建模型系统的稳态运行特性进行了仿真分析,研究了暂态情况下柔性直流单元对常规直流单元故障恢复的影响。研究结果表明:混合直流异步联网系统额定工况下运行波形稳定,参数符合工程实际,稳态性能符合要求;当逆变侧发生交流系统故障时将引起常规直流单元逆变器出现换相失败现象;柔性直流单元能够起到动态无功补偿的作用,有助于常规直流单元的故障恢复。
In 2016,Southern Power Grid built the first hybrid HVDC project of the world—Luxi BTB(back-toback)HVDC project.In order to analyze its steady state operation and fault recovery characteristics,this paper establishes a hybrid DC asynchronous interconnection system model including LCC-HVDC and VSC-HVDC in PSCAD/EMTDC simulation platform.Based on Luxi BTB HVDC project,we construct the main circuit and control system mode of LCC-HVDC and VSC-HVDC respectively,which form the hybrid DC asynchronous interconnection system in parallel to simulate and analyze the steady-state operation characteristics of the proposed model system.Then,we investigate the influence of MMC-HVDC on the fault recovery of LCC-HVDC under transient conditions.The results show that the operating waveform of the hybrid DC asynchronous interconnection system is stable under the rated conditions.The parameters and the steady-state performance meet the requirements of the project.When the AC system fault occurs on the inverter side,the commutation failure occurs in LCC-HVDC.MMC-HVDC can play the role on dynamic reactive compensation,which is helpful to restore the faults in LCC-HVDC.
出处
《分布式能源》
2017年第6期52-58,共7页
Distributed Energy
