1、 外文资料翻译 Composite insulator With the economic and social development of electric power, the safety and reliability of the operation put forward higher request. Data shows that: high voltage grid operation fault is mostly due to poor insulation, and high-voltage lines insulator is the weak link of hi
2、gh-voltage grid insulation. Therefore the operation condition of insulator were charged detection, to ensure safe and stable operation of the grid has important realistic significance. Composite insulator to light weight, high mechanical strength, good pollution resistant, easy operation and mainten
3、ance etc in countries in the power system has been widely applied. But with the use of composite insulators lines of composite insulators, had appeared in the operation of all kinds of questions. These problems have caused all scholars and power system of personnel. Therefore, the study of composite
4、 insulators insulation fault detection technology, reliable operation of the power is an important work to ensure safe operation of the power grid, has the extremely vital significance. The defects of composite insulators including inside and outside insulation insulation defects. Inner insulation d
5、efects in appearance is difficult to find, at the same time, they are the most dangerous defects, therefore, the difficulties of the composite insulator defects detection mainly lies in the inner insulation defects. This study of the inner insulation composite insulator defect detection methods. Thi
6、s also applies to the outer insulation composite insulator detecting defects. At present, the detection of composite insulators in charged of technology research is very active, mainly by detecting technology: observation and ultraviolet imaging method, the method of infrared measuring temperature a
7、nd electric waves, etc. General: infrared measuring temperature and electric method is satisfactory in two ways. The composite insulator electric decomposing along the longitudinal component and insulator along the radial direction, insulator radial electric components, the proportion of small negli
8、gible. Longitudinal electric component is about equal to the composite insulator electric field, in the longitudinal electric component can test the defects of composite insulators. No defect composite insulator electric intensity vertical component E along the axial insulator curve. The composite i
9、nsulator field distribution is not uniform, high-pressure electrode potential line near field for high dense, middle part, the distribution of electric field, electric voltage electrode near. Show U glyph. The composite insulator potential distribution is not uniform. When the insulator intermittent
10、 existence defects (including sheath infinconnective defects and mandrel, due to the defect of inconnectiveinf electric field intensity E is the length of the potential, thus this vertical variation, electric field intensity will suddenly the electric field distribution curve, but also no longer smo
11、oth in the corresponding position have aberration (middle), sink, ends, therefore, is measured by the longitudinal field distribution of composite insulators, can find the inner insulation composite insulator intermittent fault. When the insulator exists when air gap (including sheath of air gap and
12、 mandrel air gap), in the external electric polarization, the local field air gap with different shapes of air gap with different ratio increases, the air-gap may occur ionization. So heres a longitudinal field intensity will suddenly, the electric field distribution curve is not smooth, but in the
13、corresponding position have distortion, the paper defects in setting for sheath triangle shape air-gap defects, defects along the surface condition of composite insulators electric distribution along the surface potential distribution, without obvious changes here. Composite post insulator to effect
14、ively use the narrow corridor, applicable to open pressure city network technology, can reduce tower height, can save lots of human, material and financial resources, due to its high bending strength, can prevent porcelain crossarm cascade, is the porcelain of product, Small volume, light weight, sh
15、ock, impact resistant capability is strong, no artificial cleaning, to guarantee safe operation. This product adopts the overall design of the stick, compact structure, high quality and weight is the same level porcelain insulator and glass of 10, transportation is very convenient installation. Appl
16、icable to uncleanness, high mechanical drawing load, big span and compact lines. Lightning pressure than with dirt and glass ceramic insulators, improve level 30-50%. In - 60 - + 200 degrees environment temperature stable performance, Using the breakdown type design, operation without measurement of
17、 zero value. Electrical performance, high mechanical strength, internal bearing epoxy glass lead pulling tensile flexural strength than ordinary steel twice, high intensity of ceramic materials of 8 10 times, effectively improve the reliability of the safe operation. Pollution resistant, good resist
18、ance, good resistant properties, its strength pollution flashover voltage tolerance and filthy wet tolerance for the same voltage up from the porcelain insulator 2-2.5 times. And dont need cleaning, can in heavy impurity to safe operation. Small volume, light weight, only for the porcelain insulator
19、 with voltage grade 1/6 1/9).The structure to be dexterous, convenient transportation and installation. Composite post insulator have different roles in different types, structure height and creepage distance is different, composite insulator is mainly used in substation, the pillar with good hydrop
20、hobic, aging resistance, tracking and electrical erosion, high tensile strength and flexural strength, high mechanical strength, impact resistance, shockproof and brittle performance is good, light weight, easy installation and maintenance, the upper end of the installation dimensions and the corres
21、ponding porcelain post insulator installation the same size, used interchangeably. 复合绝缘子 随着社会经济的不断发展，对电力运行的安全性和可靠性提出了更高的要求。资料表明 :高压电网运行故障多半是由于绝缘不良所引起的，而高压线路绝缘子是高压电网绝缘的薄弱环节。 对其进行 检测，对于保证电网安全、稳定运行具有重要的现实意义。 复合绝缘子以重量轻、机械强度高，耐污性能好、运行维护方便等优点在各国电力系统中得到了广泛应用。但随着线路复合绝缘子的大量使用，复合绝缘子在运行中已经出现了各种各样的问题。这些问题已引起各国学
22、者和电力系统工作人员的高度重视。因此，研究复合绝缘子绝缘缺陷检测技术，是保证电力运行可靠性的一项重要工作，对于保证电网安全运行具有十分重要的意义。复合绝缘子的缺陷包括内绝缘缺 陷和外绝缘缺陷。内绝缘缺陷在外观上是难以发现的，同时它们又是最危险的缺陷 ,因此 ,复合绝缘子缺陷检测的难点主要在于内绝缘缺陷。本文研究复合绝缘子内绝缘缺陷的检测方法。此法同时也适用于检测复合绝缘子的外绝缘缺陷。 目前，国内外针对带电检测复合绝缘子技术的研究十分活跃，主要采用的检测技术有：观察法、紫外成像法、红外测温法、声波法和电场法等。一般认为 :红外测温法和电场法是效果较好的两种方法。 复合绝缘子的电场可分解成沿绝缘
23、子的纵向分量和沿绝缘子的径向分量，径向电场分量所占的比例很小，可忽略不计。纵向电场分量约 等于复合绝缘子的电场 ,在现场可用纵向电场分量检测复合绝缘子的缺陷。无缺陷复合绝缘子电场强度纵向分量 E 沿绝缘子轴向的变化曲线。复合绝缘子沿面场强分布很不均匀，高压电极附近电位线密集，为高场强区，中间部分电场分布较均匀，低压电极附近电场有所回升。显 U字形。复合绝缘子沿面电位分布很不均匀。 当绝缘子存在导通性缺陷时 (包括护套中导通性缺陷和芯棒中导通性缺陷 )，由于电场强度 E 是电位沿长度的变化率，因此此处的纵向电场强度将突然降低，做出的电场分布曲线也不再光滑，而是在相应的位置上有畸变 (中间下陷，两
24、端上升 )，由此可见，通过测量复合绝缘子的纵向电场分布，可以找出复合绝缘子的内绝缘导通性故障。当绝缘子存在空气隙时 (包括护套中空气隙缺和芯棒中空气隙 )，在外部电场的极化下，气隙中的局部场强随气隙形状的不同而有不同倍数的升高，气隙中有可能发生电离。因此此处的纵向电场强度将突然增大，做出的电场分布曲线也不再光滑，而是在相应的位置上有畸变，本文缺陷人为设定为护套中三角状空气隙缺陷，缺陷状态下复合绝缘子沿面电场分布沿面电位分布无明显变化，此处省略。由此可见，通过测量复合绝缘子的纵向电场分布，可以找出复合绝缘子的内绝缘导通气隙 性缺陷。 复合绝缘子是一种特殊的绝缘控件，能够在架空输电线路中起到重要作用 。 早年间绝缘子多用于电线杆，随着科技的发展，慢慢发展于高型高压电线连接塔的一端挂了很多盘状的绝缘体，它是为了增加爬电距离的，通常由玻璃或陶瓷制成，就叫绝缘子。绝缘子在架空输电线路中起着两个基本作用，即支撑导线和防止电流回地，这两个作用必须得到保证，绝缘子不应该由于环境和电负荷条件发生变化导致的各种机电应力而失效，否则绝缘子就不会产生重大的作用，就会损害整条线路的使用和运行寿命 。 复合绝缘子可分为：复合悬式绝缘子，复合针式
