电压

By means of discharge test on air clearance of real size simulation tower head , the discharge characteristics of UHVDC tower air clearances under DC pre-voltage superimposed with switching surge are researched and the test data are obtained.

通过真型尺寸模拟塔头空气间隙放电试验，研究了特高压线路杆塔空气间隙在直流预电压叠加操作冲击下的放电特性，得到了叠加电压的试验数据。

The charge pump can output a step-up and a step-down voltage simultaneously with a high driving capability.The multiple gain pair technique was introduced to enhance its efficiency.The proposed co-use technology for capacitors and switch arrays reduced its cost.

该电荷泵能同时提供具有驱动能力的升压和降压模式电压输出，且可实现可变增益组合，以便根据检测到的输入电压自动调整增益组合以提高工作效率。

Main Products has combined three-phase overvoltage protection , high-low-voltage reactive power compensation and filtering device, high voltage current-limiting fuse combination of protective devices, high-capacity high-speed switches, arc and over-voltage protection devices and power quality management products, all products have independent intellectual property rights.

产品主要有三相组合式过电压保护、高低压无功补偿及滤波装置、高压限流熔断器组合保护装置、大容量高速开关、消弧及过电压保护装置及电能质量治理产品，所有产品均拥有自主知识产权。

Group main products are: three-phase modular overvoltage protectors, high voltage current-limiting fuse combination of protective devices, de-excitation of synchronous generator rotor device, large-capacity high-speed switching device, extinction arc and over-voltage protection device, computer system protection device, intelligent switchgear, etc., series, nearly a hundred kinds of products.

集团主要产品有：三相组合式过电压保护器、高压限流熔断器组合保护装置、同步发电机转子灭磁装置、大容量高速开关装置、消弧及过电压保护装置、微机系统保护装置、智能开关装置等七大系列，近百种产品。

In this paper a new contingency screening and ranking method is formed by combiningiterative filtering screening technology with continuation power flow analysis. Researchingpreventive control policy in reactive power compensation and load control when themargin of stability is serious, and reciprocal math model is given;through the exempleof IEEE39 typical system , the availability of the discussed methods in this dissertationwas approved. Aimed at the real grid, the contingency screening analysis and preventivecontrol policy based on Beijing power grid is discussed;the static voltage stabilityanalysis software based on figure draw of Beijing grid is realized, and the software hasthe junction to BPA .

论文提出了将迭代过滤筛选技术和连续潮流法相结合的事故筛选分析方法；从无功补偿控制和负荷控制两方面研究了系统裕度紧张时的预防控制策略，给出了相应的数学模型；采用IEEE39节点的标准系统算例，验证了本文提出的静态电压稳定事故筛选分析方法的可行性；针对实际电网讨论了基于北京电网的事故筛选分析和预防控制策略；通过与BPA接口实现了基于北京电网图形平台的静态电压稳定分析软件。

The electromagnetic structure of voltage transformer,including the turns of secondary winding,the wire cross sections of primary and secondary windings,is optimized with the methods based on the finite analysis theory. The comparison between voltage transformers with and without optimization shows the magnetic field distribution is more reasonable in optimized voltage transformer,which enhances its magnetic field and reduces its size.

应用ANSYS有限元分析中的优化设计技术，对电压互感器的电磁结构(二次绕组匝数及一、二次绕组导线的截面积)进行优化，通过比较优化前后的结果，可以看出优化后电压互感器内部磁场分布更为合理，线圈中磁场的增强有助于进一步减小铁心的体积。

Behavior of welding arc plasma,characteristic of welding voltage,local changes of electron temperature and electron density were investigated respectively with high speed camera,inductance gauge of current and voltage,spectrometer in low power YAG laser-gas metal arc welding hybrid welding process comparing with simple GMAW welding case.

采用高速摄像机、电流电压采集仪及光谱分析仪分别研究低功率YAG激光-熔化极气体弧焊复合焊接过程中的电弧形态、电压特点及局部电子温度、密度变化。

A novel MOS-only voltage reference is presented, which is based on the threshold voltage difference between p-type and n-type MOSFETs. Its precision is improved by the cancellation of the process variation.

提出了一种新的纯MOS结构的基准电压源，它利用pMOS和nMOS的阈值电压差来抵消工艺偏差，提高了基准的精度。

A novel MOS-only voltage reference is presented, which is based on the threshold voltage difference between p-type and n-type MOSFETs. Its precision is improved by the cancellation of the process variation.

提出了一种新的纯MOS结构的基准电压源，它利用PMOS和nMOS的阈值电压差米抵消工艺偏差，提高了基准的精度。

The fault phase and the ground fault generator with the current difference larger than its threshold are thus detected,and the selectivity protection scheme is also presented.

目前国内外已开发的发电机定子接地保护有零序基波电压和三次谐波电压构成的100%定子接地保护、外加电源式定子接地保护等[3~6]。

The concept of equivalent rotationally rigidity is offered and the formula of rotationally rigidity is obtained.

主要做了如下几个方面的工作：对伸臂位于顶部的单层框架—筒体模型进行分析，提出了等效转动约束的概念和转动约束刚度的表达式。

Male cats normally do not need aftercare with the exception of the night after the anesthetic.

男猫通常不需要善后除了晚上的麻醉。