基于直流限流电路的直流单极接地故障自适应重合闸技术  

An Adaptive Reclosing Technology for DC Pole-to-ground Fault Based on DC Current Limiting Circuit

作　　者：王常骐 路佳宁 洪玮 信赢 李斌 WANG Changqi;LU Jianing;HONG Wei;XIN Ying;LI Bin(School of Carbon Neutrality Science and Engineering,Anhui University of Science and Technology,Hefei 231131,Anhui Province,China;State Grid Baoding Electric Power Supply Company,Baoding 071000,Hebei Province,China;School of New Energy and Intelligent Connected Vehicle,Anhui University of Science and Technology,Hefei 231131,Anhui Province,China;School of Electrical and Information Engineering,Tianjin University,Nankai District,Tianjin 300072,China)

机构地区：[1]安徽理工大学碳中和科学与工程学院,安徽省合肥市231131 [2]国网河北省电力有限公司保定供电分公司,河北省保定市071000 [3]安徽理工大学新能源与智能网联汽车学院,安徽省合肥市231131 [4]天津大学电气自动化与信息工程学院,天津市南开区300072

出　　处：《电网技术》2023年第12期4877-4886,共10页Power System Technology

基　　金：安徽理工大学高层次引进人才基金(13230018);国家自然科学基金项目(52107023)。

摘　　要：为避免柔性直流系统重合于永久性故障,造成二次过流冲击从而威胁系统安全,需采用预先判断故障性质的重合闸方法以确保系统的有效重启和可靠恢复。针对配置有混合式直流断路器的架空线柔性直流输电系统,提出一种基于直流限流电路的直流单极接地故障自适应重合闸技术。首先,提出直流限流电路拓扑结构并分析其工作原理,该拓扑由限流单元、吸能单元和故障性质判别单元组成,与混合式直流断路器串联接入直流线路。此后,结合故障发展过程,理论计算各阶段故障暂态电流、暂态电压的表达形式,并提出直流限流电路各元件的参数选择依据。最后,在PSCAD平台搭建系统模型并进行故障仿真,仿真结果表明所提自适应重合闸技术能准确判断故障性质,并具备较好耐过渡电阻能力。When the flexible dc grid recloses to a permanent pole-to-ground fault,a secondary overcurrent impact will be caused and then the system security will be threatened.In order to avoid this situation,a reclosing method that pre-judges the fault nature is required to ensure the effective restart and reliable recovery of dc system.Under the condition of the overhead line flexible dc system with hybrid dc circuit breaker,an adaptive reclosing technology for dc pole-to-ground fault based on dc current limiting circuit is proposed.Firstly,the topology of dc current limiting circuit is proposed and its working principle is analyzed.The topology is connected into dc line in series with hybrid dc circuit breaker,which is composed of current limiting unit,energy absorbing unit and fault nature identification unit.Then,combined with the dc fault development process,the equations of transient current and transient voltage in each stage are calculated theoretically,and the parameter selection method of each component of dc current limiting circuit is proposed.Finally,the dc pole-to-ground fault simulation is carried out in PSCAD platform,the simulation results show that the proposed adaptive reclosing technology can accurately identify the fault nature and endure great fault resistance.

关 键 词：直流故障限流 柔性直流电网 直流单极接地故障 自适应重合闸 

分 类 号：TM721[电气工程—电力系统及自动化]