电弧

Based on the analysis of three-dimensional power conductor for DC arc furnace, the electric arc deflection model was set up and the control system of the arc direction was configured. According to the bus bar distribution at the bottom electrodes cooled by water, the arc direction control principle and its configuration were described, The simulation results show that the control system can restrain the electric arc deflection and control the arc direction.

在分析直流电弧炉三维导体布置的基础上，建立了直流电弧的偏工以此作为电弧位置控制的依据，针对水冷钢棒式底电极型的直流电弧炉，阐述了其电弧位置控制的原理和系统组成，并进行了仿真研究，结果表明控制系统可以有效地纠正电弧的偏向总是并可控设定点自由控制电弧以位置。

This paper provides a simple, feasible way to simulate the electric characteristic of electric arc furnace.

在模拟电弧炉电弧电气特性上探索出了一种可行的、简单的方法，能够模拟出和实际电弧炉主电路相一致的外特性，能够满足电弧炉电弧控制试验的需要。

The effects of control parameters circuit characteristics and different smelting stages on electric arc impedance are considered.

该模型考虑了电弧控制参数、线路特征及冶炼不同阶段对电弧阻抗的影响，用Matlab实现了电弧炉模型的仿真，进行了谐波分析的仿真研究，给出了电弧电压与电弧电流的仿真波形图。

When τ's value was less than 0.1, the HCVAW arc was exhibitive of diffusedshape with lower energy density instinct; and when τ's value was higher than 0.5,the arc was a fine-constricted arc with higher energy density.

在电弧电流密度超过临界值时，电弧自生磁场对电弧产生的收缩作用超过了电弧中各种粒子的扩散作用，HCVAW电弧由此而发生了形态上的转变。

Firstly, electrization knowledge related to the research is introduced. After a deep study on various contact loss detection techniques, especially on the electric arcs detection techniques, we draw the conclusion that the untouched detection technique based on phototube sensor can acquire exact contact loss information, and will to be the leading technique for contact loss measurement in future. Secondly, combining with the special railways system in our country, we analyze the cause of the arcs, and the influence on the power supply system and the on board traction drive due to the arcs in detail, and study the arcs' spectrum characteristic. We also analyze detecting principles and put forward with a method - using phototube sensor to detect the contact loss arcs, conceive the configurations and detection flows of the measurement.

文章通过对电气化铁道相关知识的了解及对国内外离线检测技术的深入了解，尤其是对离线电弧检测技术的了解，总结出了基于光电传感器的非接触离线电弧检测系统能够得到准确的弓网离线情况，并且是国内外检测技术的发展方向；文章详细的分析了离线电弧产生的原因，电弧对机车牵引动力的影响情况，研究了我国铁路系统中离线电弧的光谱特征分布；分析了系统的检测原理，提出了采用光电传感器实现对离线电弧进行检测的方法，并设计了"电力机车弓网离线电弧检测装置"的检测功能和管理功能，规划了系统的组成结构及检测流程。

The characteristic of primary arc is analyzed, and the dynamic model of primary arc is established. The line differential equation including primary arc voltage is constructed, and the parameter estimation technique is used to estimate the voltage amplitude of primary arc, so as to determine the fault type and realize adaptive three-pole-autoreclosure.

分析了一次电弧的特点，建立了一次电弧的动态模型，利用一次电弧的特点建立了包含电弧电压的超高压输电线路相间短路的线路微分方程，通过参数估计的方法求得故障点的电弧电压，以判断故障类型，实现自适应三相重合闸。

Simulation results also show that saddle-shaped distributed AMF can more effectively inhibit constriction of vacuum arc.

对于小电流扩散态真空电弧，重点仿真分析不同电弧电流与不同纵向磁场对其关键特性的影响，部分仿真结果进行了实验验证；对离子处于超音速流动的收缩态真空电弧的仿真表明，真空电弧的磁收缩主要是由于霍尔效应引起的，离子温度和电子温度沿轴向先增大后减小，马鞍形分布的纵向磁场能够更有效地抑制真空电弧的收缩，而且阴极斑点分布对真空电弧特性也有着显著的影响；对离子处于亚音速流动状态的大电流真空电弧的仿真表明，部分等离子体不能到达阳极而损失，马鞍形分布的纵向磁场能够更有效地抑制电弧等离子体的损失，同时能使阳极电流密度和能流密度的分布更加均匀。

The design and make of a simple electric arc plasma generator;2. Mathematics expressions of arc curr en t are deduced considering the circuit resistance of the arc furnace,based on the assumption that electric arc voltage follows rectangle wave,and the elect ric parameters related to continuous and non-continuous electric arc are obta ined.

推导了在假定电弧电压为矩形波条件下，电弧电流的瞬时值数学表达式，明确了电弧连续性与随操作参数I/Is之间关系，推导中考虑了线路电阻的影响；分别求得了电弧连续与不连续情况下的无量纲电气参数；得到了电弧连续性准则；给出了计算临界功率因数的线性高精度近似计算式。

A computerized welding arc spectrum information sampling and processing system are developed to study of the ultraviolet spectrum distribution feature. Corresponding softwares also is developed. A process for sampling the ultraviolet spectrum automatically and the real-time monitoring of welding parameter are realized. based on the principles of the physics of arc and spectroscopy the information of welding arc ultraviolet spectrum sampled is changed and processed.

焊接电弧紫外光谱信息的计算机采集与处理系统*韩国明吴钊柳刚云绍辉李俊岳摘要以焊接电弧紫外光谱的分布特征为研究对象，研制了一套焊接电弧紫外光谱计算机采集与处理系统并开发了相关软件，实现了紫外光谱采集过程的自动化、焊接电流与电弧电压的实时监测，并在电弧物理和光谱学原理的基础上，对采集的焊接电弧紫外光谱信息进行变换和处理。

To improve the stability of Arcjet discharge plasma in low current and high voltage mode, research on the demand of output characteristics of Arcjet Power Conditioning Unit was conducted. In this paper, based on PWM invertors and current mode control, using MOSFET as the main power device, an Arcjet Power Conditioning Unit was developed. Through adding a closed loop feedback circuit of output voltage, it can make the output characteristics of PCU be positive resistance to ensure the stability of Arcjet discharge plasma. The experiment indicates that this PCU can make Arcjet engine work at high voltage mode (100 V, 10 A) and ensure the stability of arcjet discharge plasma. Finally, it provides the experimental data of Arcjet when working.

为了解决小电流、高电压下电弧火箭等离子体的稳定性问题，研究了电弧火箭发动机对电源调理单元的输出特性要求，基于逆变电源脉宽调制技术与峰值电流型控制原理，以MOSFET为主功率器件，研制了一台电弧火箭电源调理单元，给出了Arcjet工作时的实验数据，通过增加PCU输出电压的闭环反馈电路，可以使PCU的输出外特性呈现正阻性，保证电弧的稳定燃烧，实验结果表明，该电源调理单元能使电弧火箭发动机达到高电压工作模式(100V， 10A)，保持电弧工作的稳定性。

Neither the killing of Mr Zarqawi nor any breakthrough on the political front will stop the insurgency and the fratricidal murders in their tracks.

在对危险的南部地区访问时，他斥责什叶派民兵领导人对中央集权的挑衅行为。

In fact,I've got him on the satellite mobile right now.

实际上 我们已接通卫星可视电话了