Diffuse diffracted features and ordered domain structures in GalnP layers grown by organometallic vapor phase epitaxy

Transmission electron diffraction (TED) and transmission electron microscope (TEM) studies have been made of organometallic vapor phase epitaxial Ga_xIn_1−xP layers (x ≈ 0.5) grown at temperatures in the range 570–690°C to investigate ordering and ordered domain structures. TED and TEM examination shows that the size and morphology of ordered domains depend on the growth temperature. The ordered domains change from a fine rod-like shape to a plate-like shape as the growth temperature increases. The domains are of width 0.6∼2 nm and of length 1∼10 nm. Characteristic diffuse features observed in TED patterns are found to depend on the growth temperature. Extensive computer simulations show a direct correlation between the ordered domain structures and such diffuse features. A possible model is suggested to describe the temperature dependence of the ordered domain structure.     

色散与损耗对无源波分在5G前传应用中的影响分析

无源波分在5G前传网络中得到了广泛的应用,但由于光纤色散在粗波分复用系统中无法忽略,且迫于成本原因没有做色散补偿,导致复用比为1:12和1:18的无源波分后6波存在较大色散代价,限制了其传输距离,成为了无源波分应用的一大瓶颈。本文首先从光纤色散的原理出发,结合传输链路损耗进行综合分析,给出了两者与传输距离间的关系。并根据厂家提供的参数建立覆盖模型,对常见无源波分类型进行覆盖分析,最后结合分析结果给出了无源波分的4种主要应用场景与使用建议。     

适用于任何具体结构的输电线路精确故障定位

针对输电线路的实际结构,提出了一种适用于任何具体结构的超高压输电线路的精确故障定位方法。该方法 基于模分析理论,采用矩阵特征值和特征向量原理,对多导线波动方程进行矩阵相似变换, 得到互相独立的 模量上的波动方程,分别对每个模量波动方程求解后,将计算结果反变换到相量。该方法很好地克服了输电 线参数实际上的不平衡对故障测距精度的影响,既适用于不换位线路 ,也适用于各种换位线路。计算机数字 仿真试验结果表明,其测距结果十分准确。     

美国西部协调委员会可靠性准则简介

介绍美国西部协调委员会所制订的新的可靠性准则。重点介绍输电系统规划可靠性准则以及系统最小运行可 靠性准则,以期能在我国电力系统可靠性准则制订中起到借鉴作用。     

试论水压凿岩机

分析了国内外液压技术及凿岩设备的现状和发展趋势,阐述了水压传动和水压凿岩机的研究内容和应用前景。     

无人值班变电站若干问题的探讨

结合实际对当前无人值班变电站建设中的一些问题进行了分析,并针对相关的几个技术问题提出了一些建议。     

Rocket-triggered lightning experiments on zinc oxide arresters and their applications to power transmission lines

In measurements of rocket-triggered lightning current and voltage performed between 1986 and 1995 on the mountain top of Okushishiku in the Kanazawa area, the authors succeeded in artificially inducing winter lightning to arresters. Using the data obtained from those measurements, we analyzed the energy absorption characteristics of surge arresters, such as are installed on every transmission line tower for three phrases, by EMTP. The energy withstand capability of an individual arrester was verified to be approximately the same as the expected value. The analysis results for the energy share of each arrester connected in parallel showed that the usual light duty arresters installed on every tower have the possibility to be able to absorb extreme winter lightning energy even if the lightning hits the power line directly. © 1998 Scripta Technica. Electr Eng Jpn, 122(4): 25–33, 1998     

特高压交流1000 kV示范工程故障电流谐波分析

根据国家电网公司提供的交流特高压示范工程二次系统研究用关键参数与边界条件,采用输电线路分布参数法,理论计算晋东南—南阳—荆门交流示范工程充电合闸、不同位置故障的电流谐波分布,了解特高压1000kV交流输电短路的过渡过程可能出现的现象及对继电保护的影响,对1 000 kV交流示范工程的继电保护研究具有一定的指导意义。     

500kV 长线路故障测距仪的 16 位微机系统

介绍了用８０８６ＣＰＵ设计的故障测距仪的１６位微机系统。该系统具有程序、数据空间大的特点,能支持复杂的以解长线方程为基础的长线故障测距软件。用ＡＳＭ８６和Ｃ语言编写,具有双精度浮点数和双曲复函数及复杂数学运算的软件可以固化在该系统的ＥＰＲＯＭ中,在无操作系统支持的环境下运行。     

光电子集成技术及其应用

本文讨论有关ＯＥＩＣ材料和工艺的若干问题，并展望其在各种领域中的应用前景。