接地方式对变电站自动化系统的影响

Effect of grounding modes on substation automation system

介绍了某变电站自动化系统几年来的运行情况,说明雷电事故可归纳为电源部分和弱电部分遭到影响和破坏。二次弱电部分的网络通信阻塞,主要是设备接地不合理,指出对低电平的弱电系统,为防止地电位不平衡造成环流引起的干扰,应该按一点接地原则而采取防范措施。对电源部分接地是以防雷、保安为目的;为防止高压设备对二次系统的干扰,二次系统的接地网最好与一次系统的接地网安全分开。叙述了自动化系统一、二次设备在设计、安装、调试和运行中存在的接地造成的影响;介绍了系统设备的防雷、接地、抗干扰措施。

The operation experiences of a substation automation system for several years are introduced,which show that the lightning accidents include the impact on and damage of power supply section and low voltage section. The network communication congestion of low voltage section is mainly caused by improper grounding of devices. It is pointed out that,for the low voltage system,one point grounding rule should be observed to prevent circumfluence disturbance caused by unbalanced ground potential. Grounding for the power supply section is mainly to prevent lightning for safety. It is better to separate the grounding net of low voltage system from that of high voltage system to avoid the influence of high voltage system on low voltage system. The influence of grounding mode on automation system in design, installation, commissioning and operation and the countermeasures for system devices in anti-lightning,grounding and interference-prevention are described.