摘要
在低压输配电系统中塑壳断路器(MCCB)的电子脱扣器逐步取代传统的机械热磁式脱扣装置,并有进一步普及智能化发展的趋势。为了适应断路器脱扣器电子化和智能化的发展需要,提出了一种基于热二极管的设计思路,通过利用二极管PN结压降随着温度升高而降低的特性来实现长延时保护功能,并同时利用可饱和电流互感器实现过载电流的侦测与保护。实践证明,基于热二极管的电子脱扣器可实现长延时保护和过载保护功能,响应时间和精度满足产品要求。
The electric trip unit(ETU)of molded case circuit breaker(MCCB)is replacing thermal magnetic tripping device in low voltage power distribution,and the further trend is developing intelligentization in future.In order to achieve electronization and intelligentization,this paper proposes a new solution based on the thermal diode,the relationship between PN Junction voltage and temperature is adopted to achieve long delay time protection.Meanwhile,the saturable current transformer is used for power harvesting and instantaneous protection of over load current.The result shows the electronic trip unit could achieve long delay trip and over instantaneous trip function,and the response time and accuracy meet breaker requirements.
作者
郑庆杰
陈为
Zheng Qingjie;Chen Wai(School of Electricae Engineering and Automation,Fuzhou University,Fuzhou 559895,China)
出处
《电测与仪表》
北大核心
2020年第8期140-146,共7页
Electrical Measurement & Instrumentation
基金
国家自然科学基金资助项目(51777036)。
