新能源电厂接入谐振接地系统的动态接地分区域选线技术研究  

Research on Dynamic Grounding Zonal Line Selection Technology for Resonant Grounding System in New Energy Power Plants

作　　者：匡扶正 KUANG Fuzheng(School of Electrical and Information Engineering,Changsha University of Technology,Changsha 410114,China)

机构地区：[1]长沙理工大学电气与信息工程学院,长沙410114

出　　处：《电力学报》2024年第3期239-247,共9页Journal of Electric Power

摘　　要：针对分布式新能源电厂接入传统谐振接地系统导致过电压保护失灵的问题,提出了一种基于动态接地方式的分区域选线技术。首先,分析了分布式新能源电厂的接入对传统谐振接地系统的影响;其次,针对配电网谐振接地系统的缺陷,将传统的谐振接地系统改造为动态接地系统,并采用分区域的选线方法,在分布式电源与系统中性点之间采用零序电流差动选线,其他区域采用零序电流幅值比较法选线;最后,在MATLAB/Simulink中对该方案进行了仿真验证。仿真结果表明,在动态接地方式下,发生永久性接地故障时,无论接地过渡电阻大还是小,该方法均可以有效地判定故障线路或者故障区域,缩小停电范围。所提方案具有一定的工程应用价值。Aiming at the problem of protection failure caused by the traditional resonant grounding system of dis-tributed new energy power plants connected to the traditional resonant grounding system,a regional line selec-tion technology based on dynamic grounding method is proposed.Firstly,the influence of distributed new energy power plant access on the traditional resonant grounding system is analyzed.Secondly,in view of the defects of the resonant grounding system of the distribution network,the traditional resonant grounding system is trans-formed into a dynamic grounding system,and the sub-regional line selection method is adopted,and the zero-se-quence current differential line is used between the distributed power supply and the neutral point in the system,and the zero-sequence current amplitude comparison method is used in other areas.Finally,the method is veri-fied in MATLAB/Simulink.The results show that in the dynamic grounding mode,when a permanent ground fault occurs,whether under the condition of low resistance or high resistance,this method can effectively deter-mine the fault line or fault area,reduce the scope of power outage,and have certain engineering application value.

关 键 词：分布式能源 谐振接地系统 动态接地 零序电流 相位差动保护 

分 类 号：TM91[电气工程—电力电子与电力传动] TM862