同杆并架双回线小电流接地故障特征及选线适应性分析  

Analysis of Characteristics of Non-solidly Grounding Fault in Double-circuit Distribution Lines on the Same Tower and Applicability of Line Selection

作　　者：龚辉昶 薛永端[1] 赵瑞锋 徐丙垠[3] GONG Huichang;XUE Yongduan;ZHAO Ruifeng;XU Bingyin(College of New Energy,China University of Petroleum(East China),Qingdao 266580,China;Power Dispatch Control Center,Guangdong Power Grid Co.,Ltd,Guangzhou 510600,China;Research Center for Smart Grid,Shandong University of Technology,Zibo 255049,China)

机构地区：[1]中国石油大学(华东)新能源学院,青岛266580 [2]广东电网有限责任公司电力调度控制中心,广州510600 [3]山东理工大学智能电网研究院,淄博255049

出　　处：《电力系统及其自动化学报》2023年第6期38-49,共12页Proceedings of the CSU-EPSA

基　　金：国家自然科学基金资助项目(52077221);南方电网公司科技项目(030600KK52190184,GDKJXM20198132)。

摘　　要：针对为缓解供电走廊紧张与用电需求增大的矛盾,大量单回线改造成同杆并架双回线对小电流接地故障暂稳态特征和已有选线方法适应性的影响尚未明确的问题,提出一种新的相模变换方法。建立同杆并架双回线小电流接地故障等值电路,分析线间耦合对小电流接地故障暂态与稳态特征的影响,以及当前选线方法和装置的适应性。结果表明,线间耦合不影响各出线间零模电流幅值和相位(极性)关系,已有选线方法仍然适用;线间耦合会使故障暂态电流的主谐振频率和衰减因子的分布范围增大,故选线装置的采样频率和所采用暂态信号频段范围都要适当增大。通过仿真验证了上述结果的正确性。To alleviate the conflict between the power supply corridor tension and the increase in power demand,many single-circuit lines have been transformed into double-circuit distribution lines on the same tower.The effects of double-circuit lines on the transient and steady-state characteristics of non-solidly grounding fault and the applicability of the existing line selection methods are still unclear.To solve the above problem,a novel phase-mode transformation method is proposed.The equivalent circuit of non-solidly grounding fault in double-circuit lines on the same tower is estab⁃lished,and the effect of line-to-line coupling on the transient and steady-state characteristics of non-solidly grounding fault is analyzed.In addition,the applicability of the existing line selection methods and devices is also analyzed.Re⁃sults show that the line-to-line coupling does not affect the relationship between zero-mode current amplitude and phase(polarity)of outgoing lines,so the existing line selection methods are still applicable.Since the line-to-line coupling in⁃creases the distribution range of main resonance frequency and attenuation factor of the fault transient current,the sam⁃pling frequency of the line selection device and the frequency range of the adopted transient signal should be moderately increased.These results are further verified by simulations.

关 键 词：配电网 同杆并架双回线 小电流接地故障 暂稳态特征 暂稳态选线 

分 类 号：TM713[电气工程—电力系统及自动化]