地铁110 kV变电站低压侧接地方式的选择

Selection of Ground Mode for Low Voltage Side of Metro 110 kV Substation

通过对地铁主变电站低压侧低电阻接地与谐振接地2种接地方式在供电可靠性、系统过电压和绝缘配合、继电保护的配置及选择等方面的比较,确定在地铁110 k V变电站主变压器35 k V侧采用低电阻接地方式,并提出在地铁110 k V变电站设计中应注意的35 k V出线保护配置、接地变保护配置、低电阻阻值选取等方面的问题。

By comparing the power supply reliability,overvoltage and insulation coordination between the low resistance grounding mode and the resonant grounding mode,it is determined that the low resistance grounding mode is adopted in the main transformer 35 kV side of the Metro 110 kV substation.Therefore,in the design of the subway 110 kV substation,it should pay attention to its special features,for example,35 kV line protection configuration optical fiber longitudinal difference protection,zero sequence current protection,configuration special grounding variable protection,low resistance resistance value selection and so on.