33 kV交流保护装置改造方案

33 kV AC Protection Device Transformation Plan

上世纪90年代开通的地铁线路受当时技术条件限制还使用的是继电器和PLC装置,存在的过流保护延时时间过长的不足。目前新建地铁线路供电系统中33 kV交流保护已经普遍采用综合测控保护装置,是集保护、测量、控制、通讯一体化的系列保护装置,装置以电流电压保护、光纤纵差保护、通信过流保护为基本配置,适用于地铁环网进出线、动力变、整流变、母联等设备的保护和测控,装置可独立安装于开关柜上。本文结合实践改造经验,总结出了33 kV交流保护改造方法,包括柜体外形改造、开关柜改造顺序、改造的前期工作、改造中的整体安排等。跟新开运营线路调试改造不同,这是一种在保证既有在线设备的安全运行前提上进行的改造升级,难度和风险就极高,改造经验的总结对于设备更新或大修具有重要指导意义。

Subway lines opened in the 1990s were also equipped with relays and PLC devices due to technical constraints at that time,which resulted in the insufficiency of long overcurrent protection delay.At present,the 33 kV AC protection in the power supply system of newly-built metro lines has been widely used as a comprehensive measurement and control protection device,which is a series of protection devices integrated with protection,measurement,control and communication.The de-vice is based on current and voltage protection,optical fiber differential protection and communica-tion over-current protection.It is suitable for the Metro ring network in-out line and power supply.The protection,measurement and control of transformer,rectifier,bus and other equipment can be installed independently on the switch cabinet.Based on the practical experience,this paper summarizes the transformation methods of 33 kV AC protection,including the cabinet shape transformation,the sequence of switch cabinet transformation,the pre-transformation work,and the overall arrangement in the transformation,etc.Unlike the debugging and renovation of newly opened operation lines,this is a transformation and upgrading on the premise of ensuring the safe operation of existing on-line equipment,which is extremely difficult and risky.The summary of renovation experience has important guiding significance for equipment renewal or overhaul.