Development of cable fault location method using fiber optic distributed temperature sensor

When ground-fault problems occur on a cable line, immediate fault location and restoration are required. Therefore, various new methods to locate the fault point instantaneously have been investigated to replace such conventional methods as the Murray loop method and the pulse radar method [1]. These methods require a long time to locate the fault point. One possible fault location method is to sense the temperature rise following a ground fault using a fiber optic distributed temperature sensor. Application of this method was found feasible through sensing the temperature rise at a ground-fault test using a thermocouple as a temperature sensor with test cables [4]. A power/optical composite cable was prepared experimentally and after verifying its thermal mechanical performance, the temperature rise at an incidence of a fault was determined and the anticipated performance was demonstrated in a ground-fault test. This article describes the outline of the test.     

强腐蚀环境下锚索强度指标及表观特性试验研究

利用自行制做的试验装置,以配制出的强腐蚀环境土为介质,对非预应力锚索和预应力锚索的裸筋以及对有注浆缺陷的锚索试件进行了腐蚀试验,从外观腐蚀状况和腐蚀后的钢绞线力学性能的改变特性进行了研究.结果表明:从外观上看,预应力锚索试件的腐蚀程度总体上比非预应力试件的腐蚀程度要重,含注浆缺陷的锚索试件的腐蚀程度比裸筋的腐蚀程度要重...     

Measurement methods for LCoS displays

Abstract— Two measurement methods to characterize uniformity and the absolute cell gap of LCoS images will be reviewed. These are simple to use in a production environment and have allowed major improvements in manufacture to be achieved. For the purpose of this paper, the liquid‐crystal mode used is the 45° normally black mode.     

电缆截面积计算中如何确定电导系数

在煤炭企业电缆截面积选择计算当中，如何确定电导系数的大小，是一个不能忽视的问题。本文经过分析、计算、论证给出了较为合理、准确的结果，为供电设计中电缆截面积的选择计算提供了重要的依据     

电缆材料绿色化的两大指标——毒性和有害元素的检测和分析

采用了电缆材料绿色化的两大指标———毒性和有害元素含量的两种检测方法,即细胞毒性试验和电感耦合等离子体发射光谱仪法,认为这两种方法具有简便、精确、快速和省钱等优点,文中也提供了某电缆阻水膏和某种电缆护套料分别进行毒性试验和有害元素检测和分析。     

电缆贯通线消弧线圈接地系统研究

全电缆贯通线已成为高速铁路建设中电力专业的设计标准,为解决全电缆贯通线发生单相接地故障时电容电流大等问题,采用消弧线圈接地系统是很好的解决方案.通过对消弧线圈接地系统的分析,为类似工程提供借鉴.     

35 kV及以下户外电缆雨天试验装置研制和应用

长期以来,35 kV及以下电压等级户外电缆难以在雨天进行试验.在分析雨天户外电缆试验现状的基础上,针对存在的主要问题,研制出了适合雨天的户外电缆试验装置.重点介绍该装置相对原试验装置的高压引出线改造,装置容量的提高以及增设的支撑铜排及配套避雨措施.一系列应用结果说明该装置实用效果良好.     

长岛海缆和风电场对末端电压的影响与解决方案

风电场实际发电量受来风的影响从零至最大发电量之间变化,使风电场与主网连接点的电压变动率很大。长岛风电场通过110kV海缆与大陆主电网连接,由于电缆的电容电感分布参数加剧了电压的变化。当主网往风电场送电并且输送的无功较小时需要补偿感性无功以补充电缆的充电电容,而风电场往主网送电时在风电场处需补偿容性无功。     

Study on support mechanism of pre-stressed truss cable and its application

The truss cable support technology was put forward to control the large mining height and composite mudstone strata roadway. This technique makes the steady rock in roadway slantwise top be anchor points, makes the truss cable be steady support structure through special implement, and supplied rock in anchor area with horizontal and vertical pressure which strengthens the surrounding rock＇s anti-strain capability, so it can solve the support problem in roadway with the large cross section and large mining height with mudstone strata. The support mechanism of truss cable about how to make the soft strata stabilize is analyzed by use of the mechanical method. Based on the mechanism and numerical simulation method, the truss cable support project was designed and used to the large mining setting room in eleventh mining area of Bailong Mine successfully.     

特柔软型钢丝铠装复合电缆设计探讨

本文主要探讨特柔软型钢丝铠装复合电缆的设计,根据特殊用户实际应用情况,设计出大拉力、超柔软钢丝铠装电缆,设计过程中不仅考虑电缆所应有的电性能,同时还要考虑电缆高强度抗张情况和应用中处于反复收放状态,而且所设计的电缆还要满足恶劣环境.