三绕组变压器低压侧相间后备保护分析及改进

Analysis and Improvement of Triple-winding Transformer Low-voltage Side Backup-protection for Two-phase Fault

变压器相间后备保护对低压侧相间短路故障灵敏度不足和动作时限过长 ,是外部故障造成变压器损坏的主要原因 ,分析了反应变压器低压侧相间短路的保护方案 ,提出了改进措施 ,这在变压器微机保护中应用简单易行 。

The main causation of transformer damage caused by external fault is the low sensitvity and over-time action of transformer backup protection for two fault at low voltage side.In the paper,the protection scheme and improvement on two-phase at transformer low voltage side is analyzed.It is convenient for use in transformer micro-processor protection,is very significant for system and transformer security