基于电流固有频率的VSC-HVDC直流线路保护  

A Novel Protection for VSC-HVDC Transmission Lines Based on Natural Frequencies of Current

作　　者：刘静[1] 段建东[1] 陆海龙[2] 赵召[1] 

机构地区：[1]西安理工大学自动化与信息工程学院,陕西西安710048 [2]国网汉中供电公司,陕西汉中723000

出　　处：《陕西电力》2015年第11期31-36,共6页Shanxi Electric Power

基　　金：国家自然科学基金项目资助(50707026);陕西省教育厅专项科研计划(2010JK747)

摘　　要：故障行波在故障点与线路终端之间来回反射,所形成的固有频率与故障距离有明确的数学关系。通过分析固有频率的形成,直流线路故障、电压源型换流器型(VSC)换流站故障及与VSC联接的交流系统故障情况下固有频率的区别,形成保护判据,对基于电压源型换流器的高压直流(VSC-HVDC)输电线路区内外保护进行研究。在PSCAD/EMTDC中建立VSC-HVDC系统模型,并在不同故障工况下对该保护方案的适应性进行仿真。大量的仿真结果表明,该保护在不同故障工况下均能可靠、快速动作,具有较好的适应性和实用性。Traveling wave travels between fault point and the end of the line, forming natural frequencies which have mathematical relationship with fault distance. By analyzing how natural frequencies form and the difference of the natural frequencies among dc transmission line faults, VSC converter faults and ac system faults, this paper analyzes the internal and external faults of VSC- HVDC transmission line, and forms the protection scheme based on the natural frequencies. VSC-HVDC model is established in PSCAD/EMTDC and lots of simulations on different fault conditions are done with this model. The results show that this method can work precisely and quickly under different fauh conditions and has good adaptability and practical values.

关 键 词：电压源型换流器型直流输电 固有频率 线路保护 

分 类 号：TM771[电气工程—电力系统及自动化]