基于单端暂态量的MMC-MTDC直流线路故障辨识方法  

Fault Identification Method for MMC-MTDC DC Line Based on Single-ended Transient

作　　者：付华[1] 陈浩轩 丰胜成[2] 孟详峰 FU Hua;CHEN Haoxuan;FENG Shengcheng;MENG Xiangfeng(Faculty of Electrical and Control Engineering,Liaoning Technical University,Huludao 125105,China;Shanxi Lu’an Environmental Protection and Energy Development Co.,Ltd,Changzhi 046031,China;State Grid Jinzhou Power Supply Company,Jinzhou 121000,China)

机构地区：[1]辽宁工程技术大学电气与控制工程学院,葫芦岛125105 [2]山西潞安环保能源开发股份有限公司,长治046031 [3]国网锦州供电公司,锦州121000

出　　处：《电力系统及其自动化学报》2020年第8期26-35,共10页Proceedings of the CSU-EPSA

基　　金：国家自然科学基金资助项目(51974151,71771111);辽宁省重点实验室基金资助项目(LJZS003)。

摘　　要：在多端柔性直流MTDC(multi-terminal flexible DC)系统中,带有模块化多电平换流器MMC(modular multi⁃level converter)的直流线路的故障辨识是目前亟需解决的重大科学问题。通过分析直流线路故障期间的暂态电流和电压,提出一种基于单端暂态电流和电压的快速辨识方法。根据故障线路与非故障线路电流变化量的差异建立了故障线路辨识模型,依据正、负极暂态电压的样本标准差建立的故障极辨识模型,辨识时间短且无需两端数据通信。在PSCAD/EMTDC仿真平台搭建张北四端口柔性直流系统模型,通过算例验证了该方法能在各种故障下快速准确地辨识故障的类型,且具备一定的抗干扰性和耐过渡电阻能力,满足多端柔性直流系统对直流线路故障辨识的要求。In a multi-terminal flexible DC system(MTDC),the fault identification of DC lines with modular multi-level converters(MMCs)is a major problem that needs to be solved.By analyzing the transient current and voltage under DC line fault,a fast identification method is proposed based on single-ended transient current and voltage.According to the difference between the variation of fault line current and that of non-fault line current,a fault line identification model is established.In addition,a fault pole identification model is established based on the sample standard deviation of transient voltages at the positive and negative poles,and the identification time is short and no data communication between two ends is needed.A model of Zhangbei four-terminal flexible DC system is built on the PSCAD/EMTDC simulation platform,and the results of an example show that the proposed method can quickly and accurately identify the fault type under various fault conditions.Moreover,it has certain anti-interference performance and capability to withstand transition resistance,thus meeting the requirements of MTDC for DC line fault identification.

关 键 词：多端柔性直流系统 线路故障辨识 电流积分值 样本标准差 故障辨识模型 

分 类 号：TM721[电气工程—电力系统及自动化]