500 kV自耦变压器中性点小电抗接地的研究

介绍浙江500kV变电所自耦变压器中性点接小电抗的研究成果,分析了选用合适的电抗值、小电抗接入后系统有效接地程度的变化、变电所中接小电抗的变压器台数等方面情况,计算了各种阻值的小电抗对不同类型故障后短路电流的限制效果,摸索了浙江电网中短路电流变化的一般规律,提出了系统中有小电抗接入后应增加的短路电流校核内容,推荐了小电抗合适的阻值.

500 kV auto-transformer with neutral point grounded through small reactance

The study achievements of auto-transformers with neutral point grounded through small reactance in 500 kV substations in Zhejiang are recommended, and the appropriate reactance values, the change in the grounding effectiveness of the system after the small reactance is connected, and the number of transformers connected with small reactance in a substation are analyzed. The current limiting effects of small reactance with various values on the short-circuit current after various types of faults are calculated, and the general laws of short-circuit current variations in Zhejiang Power Grid are studied. Consequently the additional short-circuit current checking programs that should be done after small reactance is connected to a system are put forward, and the suitable reactance values are recommended.