AC 0.4 kV开关柜母联备自投PLC电源整改浅析

Scheme for Renovation of Busbar Standby Automatic Switching PLC Power Source of AC 0.4 kV Switchgear

长春城轨1号线AC 0.4 kV开关柜母联备自投PLC采用交流220 V电源模块,由变电所自用电系统交流屏供电,交流屏从变电所低压柜两段AC 0.4 kV母线各引入一路电源,作为交流所用电系统的进线电源。当交流所用电系统主供电源失压时,交流屏双切开关进行电源切换。但在切换过程中,PLC存在短暂失电重启过程,PLC重启完毕后,再控制AC 0.4 kV母联断路器备自投合闸,这就造成了本段单电源供电馈线短暂失电的情况发生。本文就该问题进行母联备自投控制电源选择分析并提出解决方案,为城市轨道交通供电系统控制电源方案提供参考。

The busbar standby automatic switching PLC of AC 0.4 kV switchgear of Line 1 of Changchun Urban Rail Transit adopts AC 220 V power module,and is supplied by the auxiliary power supply system of the substation.The AC screen introduces one power supply circuit each from the two AC 0.4 kV busbars of the low-voltage switchgear of the substation as the incoming power supply;when the main power supply of the power consumption system loses voltage,the double switch is responsible for power switching.In actual process of switching,there is a short-term process of power loss.After the PLC restarts,it will control the standby automatic switching of the circuit breaker of AC 0.4 kV busbar,which will cause a short-term power loss of the single power supply feeder in this section.With regard to this problem,the paper analyzes the selection of busbar standby automatic switching control power supply and puts forward the scheme for solution,which is able to provide the reference for making of schemes for control power source of power supply system of urban rail transit.