摘要
远距离海上风电越来越多地选择柔性直流经海缆送出的方式。采用电缆的柔性直流(voltage source converter based high voltage direct current,VSC-HVDC)输电系统,其故障特性比传统架空线直流输电系统更加复杂。文中基于对称单极拓扑的双端VSC-HVDC海上风电送出工程,简化了电缆和VSC-HVDC输电系统的数学模型,分析换流变阀侧交流系统单相接地和直流电缆线路单极接地等典型故障下的故障特性,运用叠加原理对故障机理进行解释;根据不同故障类型的故障源等效出不同的故障回路,得到了长距离电缆显著的电容效应对VSC-HVDC系统故障特征的复杂影响;利用实时数字仿真平台,搭建远海风电送出系统硬件在环仿真模型,验证了故障机理解析分析的正确性。
In recent years,offshore wind power has developed rapidly.It is the most effective way to transmit the wind power far away from the coast through the voltage source converter based high voltage direct current(VSC-HVDC)transmission system.The offshore wind power is usually transmitted by cable,which makes the fault characteristics of VSC-HVDC transmission system more complex than that of overhead transmission system.Based on a symmetrical monopole topology of two-terminal VSC-HVDC offshore wind power transmission project,the mathematical model of the transmission system which contains cables and VSC-HVDC system is simplified.The fault characteristics under typical faults such as single-phase grounding of AC system at converter valve side and single pole grounding of DC cable line are analyzed.Based on the superposition principle,the fault mechanism is analyzed in detail.According to the fault sources of different fault types,different fault circuits are equivalent.The complex influence of the significant capacitance effect of long-distance cables on the fault characteristics of VSC-HVDC systems is obtained.A real time digital simulation model of offshore wind power transmission system through VSC-HVDC is built.The fault mechanism is verified through simulation analysis.
作者
姜崇学
李钢
张宝顺
杨志强
邹凯凯
高姗姗
JIANG Chongxue;LI Gang;ZHANG Baoshun;YANG Zhiqiang;ZOU Kaikai;GAO Shanshan(NR Electric Co.,Ltd.,Nanjing 211102,China)
出处
《电力工程技术》
北大核心
2023年第2期112-118,共7页
Electric Power Engineering Technology
基金
国家电网有限公司科技项目“大规模海上风电经柔性直流送出系统继电保护及振荡抑制关键技术研究”(5100-202118029A-0-0-00)。
关键词
海上风电
长距离电缆
柔性直流(VSC-HVDC)输电
对称单极拓扑
故障特性
实时数字仿真
offshore wind power
long-distance cable
voltage source converter based high voltage direct current(VSC-HVDC)transmission
symmetrical monopole topology
fault characteristics
real time digital simulation
