摘要
电磁场通过电场耦合、磁场耦合、电磁辐射、公共阻抗耦合等方式进行传播,对电气二次系统正常工作进行干扰,严重时可能产生过电压损坏设备。采用正确的接地方式不仅能保障人身和设备安全,还能为电气二次系统正常运行创造有利条件。电缆屏蔽层一端或两端接地各有利弊,应根据实际情况正确选择。水电站安装与主接地网紧密连接的高质量等电位接地网,是提高屏蔽层两端接地时控制电缆抗干扰能力的有效措施。
The electromagnetic fields propagate by electric field coupling,magnetic field coupling,electromagnetic radiation or common-impedance coupling which can cause interference on the regular work of the electrical secondary system.When the interference becomes serious,it may damage the electrical secondary equipments because of the over-voltage.Using the correct grounding mode and technology can not only protect the human and the equipment but also create favorable conditions for the regular work of the electrical secondary system.There are advantages and disadvantages of grounding cable shield at one end or at both ends,which should be correctly selected according to the actual situation.The installation of high-quality equipotential grounding grid,which is closely connected with the main grounding grid is an effective measure to improve the anti-interference ability of the control cable when both ends of the shielding layer are grounded.
作者
单文坤
SHAN Wenkun(Datang Guanyinyan Hydropower Development Co.,Ltd.,Kunming 650103,China)
出处
《电工技术》
2020年第23期123-126,129,共5页
Electric Engineering
关键词
电气二次
接地
干扰
屏蔽电缆
等电位
electrical secondary equipment
grounding
interference
shielded cable
equipotential
