配电网混合接地运行分析

配电网接地方式改造面临小电阻接地系统同原有的消弧线圈接地系统混合运行的情况,文中以研究混合接地系统运行对原有保护的影响与改进为主要目的,对单相接地故障进行理论分析,运用实际参数建立混合接地系统模型进行单相接地故障仿真,对单独接地和混合接地系统各量进行对比分析,得出混合运行情况下消弧线圈接地系统侧的接地故障将会引起小电阻接地系统保护误动,最后提出有效的混合接地运行系统零序保护的改进方案。具有很强的工程运用价值。

Distribution Network Hybrid Grounding Operation Analysis

There is a situation of low resistance grounding systems and arc extinction coil grounding systems mixed operation in the process of substation reconstruction.It is the purpose of the paper that the influence on protection and improvement of hybrid grounding system over separate grounding system are researched.This paper show theoretical analysis of single phase to ground fault in distribution network.With substation practical parameters as the basis,a hybrid grounding model was established to make single phase-to-ground fault simulation.A comparative analysis about separate grounding and hybrid grounding system is carried on.The earth-fault of arc extinction coil grounding will cause the protection false operation in low resistance grounding system.Finally,the paper put forward the effective improvement methods of the zero-sequence current protection in hybrid grounding system.The paper has a high engineering application value.