摘要
一般工矿企业电气设备的过流保护往往采用相应额定电流的空气开关来实现,或者以发电机、配电柜等的最大供应电流限制来实现保护,这些方案准确性较差、不太安全。设计了一种工矿电气设备外置型过流报警器,利用电流互感器的一次级测量主回路的电流,二次级的感应电流串联一个采样电位器,如果主回路电流超过预定(在保证电气设备能够正常工作的前提下可以随意预定)电流,采样电阻电压点亮LED,光敏电阻被LED光照、阻值急剧降低,双稳态触发器输出高电平,切断主回路供电,同时触发多谐振荡器振荡输出矩形波,实现声光报警。这种设计可以集成到配电柜电路中,也可以独立设计为一个模块电路,该报警模块在保证负载正常工作的前提下可以随意应用到几乎所有的电气设备系统上。
Generally,the overcurrent protection of electrical equipment in industrial and mining enterprises is often achieved by using the air switch of the corresponding rated current,or by the maximum supply current limit of generators,power distribution cabinets,etc.These schemes are less accurate and less secure.An external over-current alarm for industrial and mining electrical equipment is designed.The primary circuit is used to measure the current of the main circuit,and the secondary current is connected in series with a sampling potentiometer.If the main circuit current exceeds the predetermined current(under the premise of normal operation of electrical equipment),the sampling resistor voltage illuminates the LED,the photoresistor is illuminated by the LED and the resistance value is drastically reduced,the flip-flop outputs a high level,cuts off the main loop power supply,and triggers multiple resonances,and the oscillator oscillates and outputs a rectangular wave to realize an audible and visual alarm.This design can be integrated into the power distribution cabinet circuit.More subtly,it can be independently designed as a module circuit.This alarm module can be applied to almost all electrical equipment systems without any load on the premise.
作者
崔建国
宁永香
CUI Jian-guo;NING Yong-xiang(Shanxi Engineering and Technology College,Yangquan 045000,China)
出处
《煤炭工程》
北大核心
2019年第11期159-163,共5页
Coal Engineering
关键词
电流互感器
采样电阻
发光二极管
光敏电阻
双稳态触发器
多谐振荡器
current transformer
sampling resistance
light emitting diode
photosensitive resistor
bistable flip-flop
multivibrator
作者简介
崔建国(1969—),男,山西阳泉人,副教授,主要从事工业控制计算机在工农业生产实践中的应用,E-mail:cuijianguo168@126.com。
