同分区配电网10kV侧合环冲击电流分析

Analysis of 10kV Side Loop-Closing Surge Current in Distribution Networks of the Same Partition

随着电网供电可靠性要求的不断提高,在电网检修或故障时需要在配电网侧进行合环操作,进而可能产生较大的冲击电流,影响电网的安全稳定运行。利用数学建模的方法,针对同一分区不同容量主变的合环情况,给出了合环冲击电流计算公式,并以某条10kV合环线路为例,结合实际监测数据和继电保护整定值,对正常情况及极端情况下线路冲击电流耐受情况进行分析,研究结果对电网实际运行具有较强的指导意义和参考价值。

With the improvement of power supply reliability requirement, a large surge current may be genera- ted by closing loop in distribution network in the case of power grid maintenance or fault, which will infect the safe and stable operation of grid. This paper presents the formula to calculate the surge current during closing loop of different capacity transformers in the same partition by mathematical model. A typical 10 kV loop line has also been studied to analyze the tolerance situation of surge current under normal and extreme situation based on the setting value of relay protection. The research results have significant value of guidance and reference for the grid operation.