计及换流站容量和过渡电阻影响的柔性直流配电网纵联保护  

Pilot protection of flexible DC distribution network considering influence of converter station capacity and transition resistance

作　　者：王要强[1,2] 李亚玺 梁军 韩婧[1,2] 陈剑[5] 吕忠涛 WANG Yaoqiang;LI Yaxi;LIANG Jun;HAN Jing;CHEN Jian;LÜZhongtao(School of Electrical and Information Engineering,Zhengzhou University,Zhengzhou 450001,China;Henan Engineering Research Center of Power Electronics and Energy Systems,Zhengzhou 450001,China;State Grid Henan Electric Power Company Ultra High Voltage Company,Zhengzhou 450001,China;School of Engineering,Cardiff University,Cardiff CF243AA,UK;State Grid Xinyang Power Supply Company,Xinyang 464000,China;Hulunbuir Mengdong Electric Power Construction Co.,Ltd.,Hulunbuir 021008,China)

机构地区：[1]郑州大学电气与信息工程学院,河南郑州450001 [2]河南省电力电子与电力系统工程技术研究中心,河南郑州450001 [3]国网河南省电力公司超高压公司,河南郑州450001 [4]卡迪夫大学工程学院,英国卡迪夫CF243AA [5]国网信阳供电公司,河南信阳464000 [6]呼伦贝尔蒙东电力建设有限责任公司,内蒙古呼伦贝尔021008

出　　处：《电力自动化设备》2025年第4期160-168,共9页Electric Power Automation Equipment

基　　金：中央引导地方科技发展资金资助项目(2022ZY0134)。

摘　　要：柔性直流配电网工程实际中,进行换流站设计时需要考虑其对应源荷容量的差异,传统纵联保护未考虑在该场景下的适用性。为此,对故障后换流站直流电容放电阶段进行了数学分析,并揭示了线路两侧换流站容量不同和过渡电阻较大时故障特征的变化;通过加权最小二乘法对时间窗内不同时刻的电流采样值赋予不同的权重,然后对线路两侧暂态电流进行线性拟合,基于直线斜率构造故障识别和故障选极判据。仿真结果表明所提保护方法能够有效解决换流站容量不同和过渡电阻导致的电气量相关性变化的问题,在不同的采样频率、噪声干扰和线路分布电容影响下均可有效工作。In the actual flexible DC distribution network project,the design of the converter station needs to consider the difference in the corresponding source and load capacity.The traditional pilot protection does not consider the applicability in this scenario.Therefore,the discharge stage of DC capacitor of converter station after fault is analyzed mathematically,and the change of fault characteristics is revealed when the capacity of converter stations on two sides of the line is different and the transitional resistance is large.The weighted least square method is used to give different weights to the current sampling values at different times within the time window,and the transient currents at both sides of the line are linearly fitted,the fault identification criterion and fault polarity selection criterion are constructed based on the slope of the straight line.Simulative results show that the proposed protection method can effectively solve the problem of electrical quantity correlation change caused by different converter station capacities and transition resistance.It can work effectively under different sampling frequencies,noise interference and different line distributed capacitances.

关 键 词：柔性直流配电网 纵联保护 继电保护 故障特征 过渡电阻 线性拟合 

分 类 号：TM77[电气工程—电力系统及自动化]