低抗引起接地网电流过大问题及措施研究

Study of Measures Against Excessive Current of Substation Grounding Network Caused by Low-voltage Shunt Reactor

针对某500 kV变电站在低压并联电抗器投入后,二次接地网与主接地网在低抗附近连接导致感应电流流入二次接地网,造成开关端子箱二次接地线烧坏的事件,从接地网的连接方式、抵抗投入后的强磁场、主接地网的电流分布规律等方面分析故障原因,并提出改进措施和建议。

As for a fault that the secondary grounding wire of a grounding switchgear terminal box is burnt out due to the inductive current flowing into the secondary grounding network which is linked to the main grounding network nearby the low-voltage shunt reactor upon the shunt reactor is put into operation in a 500 kV substation,the fault causes are analyzed from the aspects of connection mode of its grounding networks,strong magnetic field upon the startup of low-voltage shunt reactor,and the distribution law of main grounding network,etc.,and improvement measures are put forward.