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关键词： 局部放电   射频信号   放电量   高电压技术  

摘要： The aim of this paper was to give an overview on partial discharges under oscillating impulse *** models(void in solid,needle-plate in air and oil) were presented,which describe the stochastic discharge process and represent internal discharges in solids and corona in air or silicon ***,an air cored Rogowski coil and a sampling resistor for partial discharge(PD) measurement were developed and introduced in this *** inception and extinction voltages(PDIV,PDEV) under single oscillating impulse voltage and AC voltage were investigated with different test *** results firstly revealed that the PD inception voltage(PDIV) decreased with increasing applied voltage;secondly the PD inception voltage for three different insulating materials,showed an escalating trend with increasing frequency of the applied *** was proven that the characteristics of PD under oscillating impulse voltage were identical to the features under AC voltage,which could be measured with the phase resolved partial discharge analysis(PRPDA) *** on the reorganization and analysis of PDs under oscillating impulse voltage,the information about insulation defects was extracted from the measured data and used for estimating the risk of insulation failure of the equipment.

关键词： 高电压技术   实验室建设   实验教学  

摘要： 实验教学是专业教学中培养学生分析问题、解决问题能力和创新能力的关键环节。从高电压实验室的发展历程、总体设计、试验教学环节设置、设备配置及今后工作展望几方面出发,对高电压实验室建设进行探索和思考。

关键词： 局部放电   射频信号   放电量   高电压技术  

摘要： With the development of new insulation materials,vegetable oil-the best substitute for mineral oil-has gradually been widely used in the liquid insulation of *** investigate the influence of vegetable oil on the thermal aging rate of oil paper,Kraft paper impregnated with mineral oil and vegetable oil have been underwent thermally accelerated aging at three different *** degree of polymerization(DP) of Kraft paper was measured to indicate the aging degree of insulation *** aging rate of Kraft paper in mineral oil and vegetable oil was compared quantitatively,and results showed that vegetable oil retarded paper’s degradation rate and extended its useful *** reasons contributing to such phenomena were analyzed using X-ray Photoelectron Spectroscopy(XPS) and molecular simulation *** paper in vegetable oil had larger activation *** to the larger interaction force between water and natural ester molecules,water molecules were easily bonded with natural ester,weakening the hydrolysis process of *** was chemically modified by natural ester during the thermal aging process,and the reactive-OH(hydroxyl) groups on the cellulose became esterified with fatty acid *** molecules were firmly bounded to the ester groups on glucose produced by *** long-chain fatty acid esterified to cellulose was parallel with cellulose chains and acted as a "water barrier" to further weaken the hydrolysis process.

关键词： 局部放电   射频信号   放电量   高电压技术  

摘要： This work studies the feasibility of implementing a system for diagnosis of electrical insulation in the field based on ultrasonic noise and artificial neural *** system,proved functional under laboratory conditions,extracts spectral information from the ultrasonic noise emitted by the corona discharges in electric equipments,and correlates it with previously defined degrees of *** achieve this classification,artificial neural networks are *** results show the viability of the method in the site;nevertheless they also show that its reliability is proportional to the size and diversity of the available database.

关键词： 局部放电   射频信号   放电量   高电压技术  

摘要： This paper proposes an effective method for over-voltage classification based on the Hilbert-Huang transform(HHT) ***-Huang transform method is composed of empirical mode decomposition(EMD) and Hilbert *** kinds of common power system over-voltages are calculated and analyzed by *** on the instantaneous amplitude spectrum,Hilbert marginal spectrum and Hilbert time-frequency spectrum,three kinds of over-voltage characteristic quantities are obtained.A hierarchical classification system is built based on HHT and support vector machine(SVM).This classification system is tested by 106 field over-voltage signals,and the average classification rate is 94.3%.This research shows that HHT is an effective time-frequency analysis algorithms in the application of over-voltage classification and identification.

关键词： 华北电力大学   科学技术发展   工程技术   征稿简则   高电压技术   办刊宗旨   科技人才   研究成果  

摘要： 《电力科学与工程》是由华北电力大学主办的学术兼工程技术性期刊。国内外公开发行，月末出版。本刊以促进科学技术发展、培育科技人才为办刊宗旨。主要刊登有关发电、供电及电力企业管理方面的最新研究成果。内容包括：电力系统及其自动化、电工理论与新技术、电机与电器、高电压技术、

关键词： 科学与技术   电力系统   学报   工程技术应用   系统运行管理   自动化理论   高电压技术   科技期刊  

摘要： 《电力科学与技术学报》（ISSN1673—9140CN43—1475／TM）是长沙理工大学主办的科技期刊，季刊，国内外公开发行．主要报道电力科学理论、工程技术应用方面的最新研究成果，介绍国内外电力科技发展动态，内容包括：电力系统自动化理论及技术应用，电网技术，高电压技术，电力市场与电力系统运行管理，

关键词： high voltage technologies   nanocomposites   superconductors  

摘要： Assets in high voltage technology have to meet harsh service conditions over long lifetimes of 40 years or more. Due to environmental concerns, substitution of conventional insulating materials becomes a necessity. Because robustness and sustainability are serious requirements, only few new materials are really breaking through. At present some promising material technologies emerge with great potential applicability in high voltage engineering. This paper discusses especially nanocomposites and high temperature superconductors.

关键词： 接地保护装置   高低压开关柜   电力   高电压技术   接地电极  

摘要： 简要叙述了接地保护装置的特性,介绍了低、高压开关柜接地保护装置的结构及工作原理,并就接地保护装置在高低压开关柜中的应用进行了分析评价。

关键词： 科学与技术   电力系统   学报   工程技术应用   系统运行管理   自动化理论   高电压技术   科技期刊  

摘要： 《电力科学与技术学报》（ISSN1673—9140 CN43—1475／TM）是长沙理工大学主办的科技期刊，季刊，国内外公开发行．主要报道电力科学理论、工程技术应用方面的最新研究成果，介绍国内外电力科技发展动态，内容包括：电力系统自动化理论及技术应用，电网技术，高电压技术，电力市场与电力系统运行管理，