降低拉绳开关引起的直流系统接地故障  

Reduce Grounding Fault of DC System Caused by Pull Rope Switch

作　　者：史强 陈志强 SHI Qiang;CHEN Zhiqiang(Inner Mongolia Jingneng Power Maintenance Co.,Ltd.,Wulanchabu,Inner Mongolia 012000,China;Beijing Zhongke Xianluo Consulting Service Co.,Ltd.,Wulanchabu,Inner Mongolia 012000,China)

机构地区：[1]内蒙古京能电力有限公司,内蒙古乌兰察布012000 [2]北京中科仙络咨询服务有限公司,内蒙古乌兰察布012000

出　　处：《自动化应用》2023年第1期138-140,共3页Automation Application

摘　　要：在发电厂、变电所直流系统中,普遍采用蓄电池组作为直流电源。直流电源为给信号设备、保护、自动装置、事故照明、应急电源及断路器分合闸操作提供直流电源的电源设备。直流系统是一个独立的电源,它不受发电机、厂用电及系统运行方式的影响,并在外部交流电中断的情况下,保证由后备电源一蓄电池继续提供直流电源,所以保证直流系统的稳定运行至关重要。传统的输煤皮带机拉绳开关触点并联到跳闸回路中,回路是由直流电源控制,改进型的拉绳开关回路是在原有的二次回路上先将拉绳开关接到一个带有保险端子排的转接箱内,最后接到皮带机开关柜的交流回路中,并且通过增加断路器及扩展继电器的方法,将二次回路设计成交流、直流交替控制,克服了传统回路由于拉绳开关引起的直流接地故障,也能直观地判断某个拉绳开关故障。In the DC system of power plants and substations,batteries are widely used,as DC power supply.DC power supply refers to the power supply equipment that provides DC power supply for signal equipment,protection,automatic device,emergency lighting,emergency power supply and breaker opening and closing operation.DC system is an independent power supply,which is not affected by generator,auxiliary power and system operation mode.In case of external AC interruption,it is an important equipment to ensure that the backup power battery continues to provide DC power.So it is very important to ensure the stable operation of DC system.The contact of the traditional pull rope switch of the coal conveyor is connected in parallel to the trip circuit.The circuit is controlled by the DC power supply.The improved pull rope switch circuit is on the original secondary circuit.First,the pull rope switch is connected to an adapter box with a safety terminal block,and finally to the AC circuit of the switch cabinet of the belt conveyor.By adding circuit breakers and expanding relays,the secondary circuit is connected The design of the secondary circuit and the alternating control of DC can not only overcome the DC grounding fault caused by the rope switch in the traditional circuit,but also intuitively judge the fault of a rope switch.

关 键 词：直流系统 拉绳开关 跳闸 故障处理 蓄电池 

分 类 号：TM62[电气工程—电力系统及自动化]