直接接地装置I/O端口及接地设计  

Design of I/O ports and grounding for solidly grounded equipment

作　　者：景展[1] 余华武[2] 陈庆旭[2] 徐波[1] 

机构地区：[1]南京工程学院电力工程学院,江苏南京211167 [2]国电南京自动化股份有限公司,江苏南京210003

出　　处：《电力自动化设备》2010年第12期106-109,共4页Electric Power Automation Equipment

摘　　要：介绍了变电站微机保护和测控装置接地方式的现状,以及不同接地方式的优缺点。针对直接接地系统的微机装置中干扰入口处的信号输入/输出接口回路,利用电阻、光耦、继电器和磁珠等器件对干扰信号进行阻尼或隔离,在印刷电路板(PCB)布局上,纵向划分多道干扰拦截面,减少不同拦截面间相互耦合或窜扰,同时结合多道电容对地的干扰泄放功能,在抗干扰成本几乎不增加的前提下,增强端口抗干扰水平。对直接接地系统的屏蔽地布线方法进行了研究,提出PCB端口屏蔽地就近直接与内部数字地平面共地,可以改善屏蔽接地效果。The present grounding modes of the microcomputer protection and control units in substations are introduced with their merits and demerits.To enhance the anti-interference capability with little additional cost for the input and output circuits of solidly grounded microcomputer units,where the interferences enter,the resistor,optocoupler,relay or magnetic bead could be used to damp or isolate the interference,the vertical multi-barrier design of PCB（Printed Circuit Board） applied to reduce the intercoupling and the multi-capacitor mode adopted to discharge interference.The shield ground disposal of solidly grounded system is studied.It is proposed to directly connect the shield ground of PCB ports with the nearby internal logic ground plane,which improves the effect of shield.

关 键 词：浮地 直接接地 电磁兼容 抗干扰 印刷电路板 

分 类 号：TM862[电气工程—高电压与绝缘技术]