电气设备二次电缆绝缘受潮故障分析

Analysis of Damp Damage of Secondary Cable Insulation in Electrical Equipment

户外端子箱电缆入口处封闭不严或端子箱通风不良、无通气孔等原因而造成端子箱内部受潮甚至凝露、端子排锈蚀、电缆绝缘破坏,造成开关误动、拒动、保护异常的事故时有发生,从而引起电气设备故障并且扩大事故范围。本文从本单位220kV变电站的几起电气设备二次电缆绝缘受潮引起故障的案例,分析电气设备二次绝缘受潮原因及如何防止二次电缆绝缘故障,从而提高变电站供电可靠性。

Because the outdoor terminal box cable entrance is not tightly sealed or the terminal box is poorly ventilated,no vent hole,etc.,the inside of the terminal box is affected by damp and even condensation,terminal block rust and cable insulation damage,resulting in abnormal switch,refusal and protection exception,so that causing electrical equipment failure and expanding the scope of the accident.This paper analyzes the causes of the secondary insulation of the electrical equipment caused by the damp in the 220kV substation of the unit,and analyzes the causes and how to prevent the secondary cable insulation fault,thus improving the reliability of the substation power supply.