基于暂态电流行波突变的LCC-MMC混合双极直流输电纵联方向保护  

Longitudinal Directional Protection for LCC-MMC Hybrid Bipolar DC Transmission Based on Transient Current Traveling Wave Mutation

作　　者：高淑萍[1] 李元泽 宋国兵[2] 吕宇星 左俊杰 沈渠旺 GAO Shuping;LI Yuanze;SONG Guobing;LÜ Yuxing;ZUO Junjie;SHEN Quwang(School of Electrical and Control Engineering,Xi’an University of Science and Technology,Xi’an 710600,China;School of Electrical Engineering,Xi’an Jiaotong University,Xi’an 710049,China)

机构地区：[1]西安科技大学电气与控制工程学院,西安710600 [2]西安交通大学电气工程学院,西安710049

出　　处：《南方电网技术》2024年第2期21-29,56,共10页Southern Power System Technology

基　　金：国家自然科学基金资助项目(51777166);国家自然科学基金国际合作与交流项目(52061635105);国家电网公司总部科技项目(52094020006U)。

摘　　要：在直流线路中行波保护作为主保护应用广泛,但行波保护作为单端量的保护具有误动性较高且耐过渡电阻能力较差的缺点。在分析了行波在直流输电系统中传播特性的基础上,根据区内和区外故障时暂态电流行波变化方向的不同提出了一种基于暂态电流行波突变的LCC-MMC混合双极直流输电系统纵联方向保护。若故障时两侧暂态电流行波突变方向相同,则为区内故障,否则为区外故障。通过PSCAD和MATLAB的仿真结果表明,该保护能快速准确地识别故障,并且不受故障类型、过渡电阻以及故障发生位置距离的影响,因此具有一定的实用性。Traveling wave protection is widely used as the main protection in DC lines.However,as a single-ended protection,travel⁃ing wave protection has the disadvantages of high maloperation and poor resistance to transition resistance.Based on the analysis of the propagation characteristics of traveling wave in DC transmission system,according to the different change directions of transient current traveling wave in internal and external faults,a longitudinal directional protection based on the transient current traveling wave mutation for LCC-MMC hybrid bipolar DC transmission system is proposed in this paper.If the mutation directions of transient current traveling waves on both sides are the same during the fault,it is an internal fault,otherwise it is an external fault.The simula⁃tion results of PSCAD and MATLAB show that the protection can quickly and accurately identify the faults under different fault types,different fault resistances and different fault location distance,so it has certain practicability.

关 键 词：行波保护 混合直流输电 纵联方向保护 暂态电流行波 

分 类 号：TM721[电气工程—电力系统及自动化] TM773