继电保护用开关电源的故障分析及改进  

Fault analysis and improvement of switching power supply for the relay protection

作　　者：徐涛 吴迎霞[2] 张红超[3] 于朝辉 

机构地区：[1]许继电气股份有限公司,河南许昌461000 [2]重庆市电力公司,重庆400014 [3]国家继电保护及自动化设备质量监督检验中心,河南许昌461000

出　　处：《电力系统保护与控制》2010年第10期135-137,共3页Power System Protection and Control

摘　　要：研究了实际运行中的继电保护用开关电源存在的几种问题。从开关电源工作原理入手,分析了两种故障现象:1)输入电源波动,导致开关电源停止工作;2)开关电源的启动电流过大,导致供电电源过载告警。通过试验分别重现了以上两种故障现象,分析了故障原因:1)由于设计时未考虑保护延时放电回路,输入电压快速通断导致电源欠压保护误动作;2)启动功率一定的情况下,启动门槛设置过低,导致启动电流过大。并把改进后的开关电源与改进前的开关电源进行了对比验证。This paper analyzes several existing problems on the switching power supply for the relay protection in the actual running.According to the working principle of switching power supply,it makes an analysis of the following two malfunction phenomena： 1） after inputting power fluctuations,the switching power supply will stop running;2） too large switching power supply start-up current will lead to the power supply overload alarm.This paper reproduces the above two malfunction phenomena,and studies the causes： 1） when not taking account of the discharge of protection circuit delay in the designing stage,the rapid on-off input voltage power supply will cause the misoperation of under-voltage protection;2） two low start-up threshold will cause the too large start-up current.This paper makes a contrast test on the improved switching power supply with the original one.

关 键 词：开关电源 原理 电源故障 继电保护 改进后的电源 

分 类 号：TN86[电子电信—信息与通信工程]