过电压

It is considered that the failure of surge arrester is caused mainly by moisture ingress which characterized by local temperature rise.

0引言避雷器是用来限制由线路传来的雷电过电压或由操作引起的内部过电压的一种电气设备。

By means of simulation, the authors research the over-voltage level at AC and DC sides of converter station as well as arrestor operation condition caused by last breaker trip occurred in inverter station of UHVDC power transmission project from Yunnan to Guangdong; analyze and reveal the interrelations among over-voltage level, various operation conditions and different action delay of DC protections and propose the requirement to the time of protection coordination to ensure secure and reliable operation of equipments for the project.

文章对云广特高压直流系统逆变站最后断路器跳闸引起的换流站交直流侧过电压水平以及避雷器工况进行仿真研究，分析揭示不同运行工况、不同直流保护动作延时与过电压水平的相互关系，提出对保护配合时间的要求，以确保系统设备能安全可靠运行。

The general analysis is focused on insulation level of the autotransformer neutraland the entrance of the autotransformer after small reactance grounding. In addition, the impedancevalue of the small reactance, the protection of the neutral and autotransformer entrance, and insulation coordination is particular discussed.

本文将对500kV 自耦变中性点由直接接地改成经小电抗接地的方式后，在多种不同的运行方式下，对其中性点、主变入口处上出现的过电压进行了详细全面的分析，并在此基础上对中性点电抗器的小电抗取值、主变中性点和主变入口处的过电压保护和绝缘配合问题进行了探讨。

In this paper, a novel Crowbar control strategy is proposed to limit the over current in the rotor and the over voltage of the DC bus as well as the transient oscillation of the electromagnetic torque. Moreover, a capacitive current is injected into the grid to assist the recovery of the grid voltage.

文章提出了一种Crowbar控制策略，能有效抑制转子过电流、直流母线过电压以及电磁转矩的振荡，并可向电网注入无功电流以帮助电网电压的恢复。

Switching operations of disconnectors or circuit breakers in Gas Insulated Substation may generate very fast transient overvoltages, which are heinously detrimental to transformer and other power equipment.

摘 要：气体绝缘变电站中隔离开关等操作会产生特快速暂态过电压，这种过电压会对变压器等电力设备造成极大的危害。

The status of lightning protection and problems, especially low insulation level of lines, lack of direct lightning protection measures, misemploy of lightning arrester and imperfect earth are discussed. Associative action of lightning overvoltage may be considered as the main ...

在此基础上提出了综合防雷措施(包括规范避雷器的安装维护、改善避雷器和杆塔接地、使用塔顶避雷针、使用自动消弧装置降低配电网建弧率、限制雷电流过后的弧光接地过电压和铁磁谐振过电压等)，以提高配电网耐雷水平和供电可靠性。

Main features:- Hole spacing 2.25mm-operating voltage: 4.5 V to 24 V-switching offset compensation at 62Hz under - over-voltage Protection - VDD-pin Reverse voltage protection - Short circuit protection open-drain output is hot off - working magnetic field range: DC to 10kHz-output goes low with magnetic south pole contacts marked on the package side, while the higher magnetic flux density and area of S1, As S2-all temperature and supply voltage range magnetic parameters on-chip temperature compensation circuitry of the minimum drift - EMC meet DIN40839.

主要特点：–霍尔片间距2.25mm–工作电压： 4.5 V 至 24 V–开关偏移补偿在62Hz下–过电压保护– VDD-pin反向电压保护–短路保护漏极开路输出被热关断–工作磁场范围：直流到10kHz–输出变低用磁场南极接触封装上有标记边，而更高磁通量密度面积S1，如同S2–全温度和供电电压范围下磁参数的片上温度补偿电路的最小漂移– EMC适应DIN40839。

Aiming at mangling of electron equipment due to transient over voltage from thunder and operation between 4 and 3+1 source defend thunder equipment s is discussed.

针对雷电和操作过电压所引起瞬间过电压对电子设备系统的损坏，探讨加装电源防雷器时采用四模块和3+1模块时的性能，并进行比较和分析。

The resultant voltage appearing across the circuit consists of a high frequency component superimposing on the normal system voltage, the total being known as the restriking voltage and constituting a switching surge .

出现于电路中的电压由一高频分量迭加在正常系统电压上所组成，总称为重燃电压，且引发操作过电压。

Research indicates that distributed parameter on taper winding led to voltage oscillation during rising edge,which may create excessive voltage gradient in head of winding,the validity of MTL model is also proved.

研究表明：分布参数会引起电压谐振，冲击电压的上升沿在绕组首端产生匝间过电压；多导体传输线模型可对锥形变压器绕组的电压分布进行有效计算。

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。