过电压

This protection machine series product make use of to respond to quickly not the line presses the component , assurance the direct current system is positive, the anode, cathode and as and anodes and the potential difference of the as settle, allowing appear temporary in the direct current system conduct electricity press limit the weak electricity equipments inside the scope, thus insuring the equipments safety movement.

本保护器系列产品利用快速响应的非线性压敏元件，保证直流系统正、负极间，正极与地间及负极与地间的电位差恒定，将直流系统中出现的暂态过电压限制到弱电设备的允许范围内，从而确保设备安全运行。

This paper presents the effect of pre-insert switching on and off resistance installed on the disconnector.

在我国国家标准GB311.1-1997(高压输变电设备的绝缘配合)[3]中称之为陡波前过电压。

The insulation of apparatus in the power system is often broken by the very fast transient overvoltagewhich is caused by the operation of disconnector in gas insulate substation In this paper, a new idea for the suppressing VFTO by ferrite is put forward, and the characteristic of ferrite is analyzed.

GIS中隔离开关操作时产生的特快速暂态过电压对电力系统及其设备的绝缘具有巨大的破坏力，本文提出了采用铁氧体来抑制GIS中隔离开关操作时产生VFTO的方法，分析铁氧体抑制VFTO的优点，对VFTO的抑制效果进行了实验研究和仿真分析，探讨了具有理想抑制效果的铁氧体参数的具体要求和对理想抑制参数的铁氧体尺寸的估算方法。

In GIS, the switching of a disconnector will produce very fast transient overvoltage, which could damage the insulation of GIS and other connected equipments and produce electromagnetic interference into low voltage control systems.

气体绝缘金属封闭开关设备中隔离开关的操作会产生特快速暂态过电压，可能导致GIS本体及其相连的设备绝缘损坏，并可能产生电磁干扰，影响二次设备。

The concerned research works of VFTO is investigated.A new transient circuit model to the question of the steep front and high amplitude value of VFTO is proposed based on general transient circuit model. The numeric simulation that disconnector switched off short bus has been proceeded by using above circuit model and the comparison of results with the one based on EMTP are given.

首先针对操作GIS中隔离开关所产生的快速暂态过电压上升时间短及幅值高的特点，在一般暂态电路模型的基础上提出了新的暂态电路模型，并利用该模型，对GIS中隔离开关切断短母线的等值电路进行了数值模拟，并与电磁暂态程序的计算结果进行了比较。

A series of ZnO-V2O5 based varistor ceramics, which have homogenous microstructure, high relative density of more than 98 % and an optimum non-ohmic coefficient α of more than 50, were fabricated at 950 ℃ by traditional electroceramic fabrication process.

ZnO压敏电阻因其特有的非线性系数大、响应速度快、吸收浪涌能力强等特点被广泛作为伺服保护器件应用在各种电路中，使被保护电路免受各种浪涌电流或过电压的损坏[1]。

Gas insulated substations is used for the power system increasedly, the very fast transient over-voltages in GIS, which may damage the power equipment and adjacent devices, is paid an attention mostly.

随着气体绝缘变电站在电力系统中越来越广泛的应用，陡波前过电压对设备本身以及相邻设备的影响也就受到了越来越多的关注，为此人们也设计了多种方法来测量VFTO。

Available options include: over-voltage protection, margining, AC power fail and DC power good logic signals, and remote on/off.

可用选项包括：过电压保护裕度，交流电源故障和直流电源良好的逻辑信号，远程开/关。

In order to study the overvoltage caused by monopolar grounding fault under bipolar mode in Ultra High Voltage DCsystem,the paper analyzes the monopolar grounding fault by use of phase-modal transformation method.

为研究双极运行的特高压直流输电系统中单极接地故障过电压，采用相模变换法分析了双极运行的特高压直流输电系统单极接地故障。

Finally, the conclusions are applied to over-voltage models based on three-phase nonsynchronous closing of switches appearing in the power systems, the results in accord with the background physical meaning are obtained.

最后，将所得结论应用到电力系统中三相非同期合闸的过电压模型中，结果表明所得结论与实际背景的物理意义相吻合，同时结论的所有条件较容易验证，因此该结论具有一定的理论意义并便于在实际中应用。

However, as the name（read－only memory）implies, CD disks cannot be written onorchanged in any way.

然而，正如其名字所指出的那样，CD盘不能写，也不能用任何方式改变其内容。

Galvanizes steel pallet is mainly export which suits standard packing of European Union, the North America. galvanizes steel pallet is suitable to heavy rack. Pallet surface can design plate type, corrugated and the gap form, satisfies the different requirements.

镀锌钢托盘多用于出口，替代木托盘，免薰蒸，符合欧盟、北美各国对出口货物包装材料的法令要求；喷涂钢托盘适用于重载上货架之用，托盘表面根据需要制作成平板状、波纹状及间隔形式，满足不同的使用要求。