检索结果-南通市图书馆

Studies on the effects of moisture and ageing on charge de-trapping properties of oilimpregnated pressboard based on IRC measurement

引用

High Voltage 2019年第2期4卷 151-157页

作者： Nasirul Haque Sovan Dalai biswendu chatterjee Sivaji Chakravorti Department of Electrical Engineering Jadavpur UniversityRaja S.C.Mullick RoadKolkataWest BengalIndia NIT Calicut CalicutKeralaIndia

The dielectric properties of oil-paper insulation degrade due to moisture ingression and *** degradation significantly impacts the space charge accumulation and charge trapping behaviour in the insulation,which are vital parameters for insulation health under the high-voltage direct current *** this work,an improved model based on the isothermal relaxation current(IRC)has been developed to study the charge trapping behaviour of an oil pressboard under the influence of moisture and *** conventional IRC model considers the total relaxation current because of charge de-trapping ***,in the case of a composite dielectric like oil pressboard,dipolar relaxation also affects the relaxation *** this work,a methodology has been proposed to investigate charge de-trapping behaviour of oil-pressboard insulation considering the dipole relaxation process from IRC *** this purpose,frequency domain spectroscopy measurements and IRC measurements have been performed on oil-impregnated pressboard specimens carefully prepared in the laboratory having different ageing conditions and moisture *** presented in this work depict that charge trapping parameters,*** trap depth and trapped charge distribution are highly affected both by ageing and *** was observed that ageing leads to the generation of deeper traps,while moisture mainly enhances the density of shallow traps.

关键词： moisture trapping charge

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Application of Cole-Cole model to transformer oil-paper insulation considering distributed dielectric relaxation

引用

High Voltage 2019年第1期4卷 72-79页

作者： Sandip Kumar Ojha Prithwiraj Purkait biswendu chatterjee Sivaji Chakravorti Department of Electrical Engineering Haldia Institute of TechnologyHaldia721657West BengalIndia Department of Electrical Engineering St.Thomas'College of Engineering&TechnologyKolkata700023West BengalIndia Electrical Engineering Department Jadavpur UniversityKolkata700032West BengalIndia Electrical Engineering Department Currently at NIT Calicut on lien from Jadavpur UniversityKolkata700032West BengalIndia

Researchers have been exploring dielectric testing techniques both in time and frequency domain for insulation condition assessment of oil-paper insulated *** a practical dielectric system,dipoles are found to behave according to a distribution of elementary Debye relaxation *** distribution density functions have been proposed to characterise such many-body interaction ***-Cole diagrams can be one of the methods for studying the nature of frequency dependency of dielectric materials of complex ***-Cole plots are commonly used for characterising different materials such as dielectric mixtures,ionic liquids,cable insulating oil,polar liquids *** scope of its application for assessing transformer oil-paper insulation considering distributed relaxation process has not been explored *** present contribution discusses mathematical formulations used for transforming the experimentally obtained time domain dielectric response test data to distribution domain and further to frequency domain for obtaining the Cole-Cole *** about the influence of various operating conditions and insulation status on the Cole-Cole diagram have been reported in this *** of tests on field transformers are also *** paper attempts to employ the features of Cole-Cole diagrams as potential indicators for analysing condition of the oil-paper insulation considering distributed relaxation process.

关键词： properties structure process

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Method for identifying ageing in epoxy-mica composite insulation used in rotational machines through modelling of dielectric relaxation

引用

High Voltage 2020年第2期5卷 184-190页

作者： Nikhil Mondal Nasirul Haque Sovan Dalai Sivaji Chakravorti biswendu chatterjee Department of Electrical Engineering Jadavpur UniversityKolkataIndia NIT Calicut CalicutIndia

Dielectric response analysis,performed in time domain and frequency domain is one of the interesting methods used for condition assessment of high voltage *** this article,the degradation of epoxy-mica composite insulation which is widely used in rotating machines has been investigated through frequency domain spectroscopy *** ageing of the carefully prepared stator bar insulation sample was performed through simultaneous application of high temperature and electric field in a designated environmental chamber for specific *** study the effect of temperature,the measurements were performed at temperatures ranging from 20 to 60°C at different ageing *** experimental work,the measurement results were modelled using Havriliak–Negami model and ageing sensitive parameters were *** study the effect of temperature,the measurements were performed at temperatures ranging from 20 to 60°*** modelled results matched well with the experimental measurements and certain model parameters sensitive to the ageing condition were *** numerical relationships between the insulation status of the stator bar and the aforementioned parameters were *** was observed that the nature of the numerical relationship remains identical in the investigated temperature range,although the coefficients vary to some extent.

关键词： insulation composite relaxation

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：