改进巴氏距离算法下混合级联直流输电纵联阻抗保护优化  

Optimization of longitudinal impedance protectionfor hybrid cascaded HVDC transmission underimproved Bhattacharyya distance algorithm

作　　者：王书征[1] 李沛林 杨军炜 张金华 施渊 刘康礼[3] WANG Shuzheng;LI Peilin;YANG Junwei;ZHANG Jinhua;SHI Yuan;LIU Kangli(School of Electric Power Engineering,Nanjing Institute of Technology,Nanjing 211167,China;State Grid Nantong Power Supply Company,Nantong 226300,Jiangsu,China;School of Electrical Engineering,Southeast University,Nanjing 210096,China)

机构地区：[1]南京工程学院电力工程学院,江苏南京211167 [2]国网南通供电公司,江苏南通226300 [3]东南大学电气工程学院,江苏南京210096

出　　处：《西安工程大学学报》2024年第2期9-17,共9页Journal of Xi’an Polytechnic University

基　　金：国家自然科学基金(52107098)。

摘　　要：为提高纵联保护在LCC-MMC混合级联高压直流输电系统中的鲁棒性,提出一种基于纵联阻抗和改进巴氏距离算法的高压直流输电纵联保护方案。该方案将巴氏距离算法与纵联阻抗保护相结合,对被保护线路首末两端电气量的差异进行量化,并通过量化后的数据,进行区内外故障的判定,然后基于能量函数构建了故障选极判据,保证了保护的可靠性;在此基础上,通过分形维数构建了改进的自适应滑窗,提高了保护的速动性。最后,基于Matlab与PSCAD/EMTDC平台建立了“白江工程”±800 kV LCC-MMC混合级联高压直流输电系统模型,并对所提改进后的保护方案进行验证。仿真结果表明所提保护方案能够快速可靠地判别区内外故障并正确完成故障选极,且有着较好的耐受过渡电阻能力。To enhance the robustness of longitudinal protection in LCC-MMC hybrid cascaded HVDC transmission systems,a longitudinal protection scheme of HVDC transmission based on longitudinal impedance and improved Bhattacharyya distance algorithm was proposed.The difference of the electric capacity at the first and last ends of the protected line was quantified by combining the Bhattacharyya distance algorithm with longitudinal impedance protection in this scheme,and the faults inside and outside the area were determined through the quantified data.Then,the fault pole selection criterion was constructed based on the energy function to ensure the reliability of the protection.Furthermore,an improved adaptive sliding window was constructed by fractal dimension,which improved the rapidity of protection.Finally,the±800 kV LCC-MMC hybrid cascaded HVDC transmission system model of“Baijiang Project”was established on Matlab and PSCAD/EMTDC platforms,and the improved protection scheme was verified.Simulation results show that the proposed protection scheme can identify faults inside and outside the region quickly and reliably,correctly select fault poles and has a better resistance to transition resistance.

关 键 词：混合级联直流输电 故障特性 纵联保护 纵联阻抗 巴氏距离算法 分形理论 

分 类 号：TM77[电气工程—电力系统及自动化]