220 kV变电站大型敞开式主接线改造方案及安全因素研究

Modification Scheme and Safety Factors of Large Open Main Wiring of 220kV Substation

随着城市用电负荷的增加,运行时间长、设备老旧的变电站已难以满足供电可靠性的要求。在变电站原场地不停电改造、消防新旧系统的并用、"微机五防"系统的变化和通道的隔离,这都是大型敞开式变电站主接线改造的重要难点。通过分析运行超30年的某220 kV变电站大型敞开式设备的改造方案,利用3个主变之间相互的负荷转移实现不停电改造,并增加220 kV出线和合理布置电缆沟的方式,解决了电源与变压器之间连接的问题,利用消防运行方式的灵活切换解决新旧消防设备的并用问题,"微机五防"系统220 kV侧接入带电显示器装置,有效地保证了设备检修过程中人员和设备的安全,安全通道采取硬隔离的方式杜绝安全隐患的发生。

With the increase of urban electric loads,substations with long operating and old equipment have been unable to meet the requirements of power supply reliability.The modification in the original site of the substation and without power failure,and the combined use of new and old fire protection systems,and the change of the"microcomputer five prevention"system and the isolation of the passage are major difficulties and safety factors for the modification of the large open main wiring of substations.This paper analyzes modification plan of the large open equipment in the 220 kV Songjiang substation,which has been in operation for over 30 years,and uses the mutual load transfer between the three main transformers to achieve non-stop electricity retrofitting.The problem of the connection between the power supply and the transformer is solved by adding 220 kV outlets and laying reasonable cable trenches.The flexible switching of the operation mode of the firefighting operation system is adopted to solve the joint use of new and old firefighting equipment.The 220 kV side of the"microcomputer five prevention"system is connected to a charged display device,which effectively ensures the equipment maintenance process safety of personnel and equipment.The safety passage adopts hard isolation to prevent the occurrence of safety hazards.