前苏联1150kV交流输电线路绝缘子串的选择

介绍了前苏联选择1150kV交流特高压输电线路绝缘子串的基本原则:①必须综合考虑污秽等级、爬距的有效利用、串长、多串组合时击穿强度的变化、绝缘子形状和长期最高运行电压等一系列因素后,再确定绝缘子的几何爬距;②在特高压电网的规划设计阶段,可先根据现场污秽情况、较低电压等级线路的多年运行经验、沿规划线路布置的测试点的试验数据等,利用正态分布的办法估算线路在最大长期运行电压下的年闪络率,然后决定绝缘水平;③在难以得到实际年闪络率的情况下,可用每百公里线路绝缘子的允许年闪络率来确定绝缘水平,从而确定有效爬距,再根据质量指标(闪络梯度)来选择绝缘子的物理结构。文章还分析了绝缘子多串并联和长度变化对击穿电压的影响,指出瓷长棒绝缘子由于年故障率很低,具有广阔的应用前景。     

一种实用的绝缘电阻测试仪升压电路的设计

介绍一种绝缘电阻测试仪的组成及其工作原理,并对直流升压电路和自动量程电路作了重点介绍.     

Biomimetic Patterns in Architectural Design

Julian Vincent , Professor of Biomimetics and Director of the Centre for Biomimetics and Natural Technologies within the Department of Mechanical Engineering at the University of Bath, identifies three distinct levels at which patterns can be translated from biology to architecture. Emphasising the importance of pattern recognition in the transfer of the most abstract derivations, he demonstrates that the greatest potential for biomimetics lies in its application for problem solving rather than straightforward mimicry of biological shapes and forms. Copyright © 2009 John Wiley & Sons, Ltd.     

Optimization of insulation thickness for different glazing areas in buildings for various climatic regions in Turkey

Insulation is one of the most effective methods intended for reducing energy consumption in both heating and cooling of buildings. Selecting the right materials and determining the optimum insulation thickness in building insulation application is an important issue. In 2000, the “Thermal Insulation Requirements for Buildings” was enacted in Turkey, energy saving by limiting the energy amount used for heating in buildings being the target. In this study, the effect of the alteration of windows and exterior wall areas on the heating energy requirement of the building and on the optimum insulation thickness has been examined by using P₁–P₂ method. The study has been carried out for four degree-day regions of Turkey for various insulation materials, glazing areas, and fuel types; the results have been presented in charts. In the rest of this study, effects of different insulation thicknesses and fuel on fuel consumption and thereby on emissions of pollutants such as CO₂ and SO₂ are evaluated. For example, in the building where XPS (extruded polystyrene foam) insulation material and natural gas are used and where the ratio of glazing area to exterior wall area is 0.2 (glazing area percentage), energy saving for the four regions has been found to be 13.996, 31.680, 46.613, and 63.071 $/m², respectively, and the payback period of investment has been found to be 2.023, 1.836, 1.498, and 1.346 years, respectively. The emissions of CO₂ are decreased by 50.91% for the cases in which optimum insulation material (XPS) and natural gas are used. The emissions of CO₂ and SO₂ are decreased by 54.67% for the cases in which optimum insulation material (XPS) and fuel oil are used.     

色谱分析在变压器故障诊断中的应用和探讨

对变压器油色谱分析中出现的一些问题进行了分析,并对其处理方法进行了探讨。     

HVDC工程用交流电容器组内部绝缘配合的研究

根据超高压直流输电系统的特点和系统绝缘配合的要求,分析了HVDC工程用交流电容器组内部的绝缘配合问题,给出了单台电容器的绝缘水平、层间绝缘水平和对地绝缘水平的计算方法和选取原则。     

Simple preparation method of asphalt polyurethane foam for various insulating purposes

In this study, Asphalt PUF (asphalt polyurethane foam) was simply prepared from the point of view of industry by in-situ polymerization of a polyoxyalkylene polyol (caster oil) and an organic isocyanate 4,4′diphenyl methane diisocyanate (MDI) into asphalt emulsion media at different NCO/OH index starting from (0.8 to 1.6). The chemical reaction is confirmed by FTIR. Surface morphology is scanned with SEM. Some of selected physical tests were performed for different insulating purposes; such as sound absorption, vibration damping, thermal conductivity, thermal cycling and water absorptivity%. The results approved that the prepared foams have an excellent sound and vibration damping properties. Furthermore, they can easily fit the uneven surface because of their good shape retention. Hence, it seems to be suitable especially for engine compartment as sound and vibration insulator. In addition, the water resistance properties of these foams are important for applications requiring long-term exposure to water, such as sealant, coating and membranes for landfills, tanks and pipes.     

深水“一体化”保温测试液体系研究与性能评价

针对国内深水单层隔水管柱测试作业具有隔热性差、上部隔水管环空与下部油套环空连通会影响测试性和传压性等特点,研制了由合成多元醇与还原糖醇复配而成的低导热系数非水基液"一体化"保温测试液。并对该保温测试液进行了导热性、密度可调性、可泵性、流变性等性能的评价,实验结果表明,该测试液抗温可达150℃,导热系数为0.2428~0.2866 W/（m·K））,密度能在1.05~1.50 g/cm3或者1.50~1.05 g/cm3间由低到高或由高到低调节,150℃静止15 d的沉降降因子为0.50,25℃下表观黏度不大于70 mPa·s,4℃下静切力不大于3 Pa,具有较好的传压性,150℃下的3 d平均腐蚀速率为0.0369~0.0690 mm/a,岩心渗透率恢复值达95%以上;另外该保温测试液不仅环境友好,含油量为零,能满足GB 18420.1-2009《海洋石油勘探开发污染物生物毒性第1部分:分级》标准中一级海域使用要求,而且还可回收再利用,可大大节约测试成本。可以用于深水单层隔水管测试作业。      

芯棒镀铬装置的设计

简单描述了目前国内芯棒生产的现状,提出了芯棒表面镀铬装置存在的问题,介绍了赛瑞公司自主研发的芯棒镀铬装置的设计背景,阐述了芯棒镀铬装置的基本结构及设备特点,解决了现存的一些问题。     

高压电机绝缘老化的分析与鉴定

对高压电机绝缘老化现象的机理进行了分析探讨,联系此类技术的最新动态,提出了几种检测方法。