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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： Radio frequency(RF) measurement has become a hot issue for partial discharge ***,its application is hampered by the difficulty to establish a relationship between the RF measurements data and apparent discharge *** this paper,on the basis of an experimental model of metal protrusion,the relationship between the results of RF measurement and pulse current method(IEC 60270) was *** energy,double integration,peak voltage,peak-peak voltage and the area of RF signals were plotted versus either the apparent discharge quantity or the square of the apparent discharge quantity in order to evaluate the optimal regression *** the same time,the impact of voltage and the distance between protrusion and plate were also *** results indicate that the optimal match to a linear regression curve can be gained by plotting the RF signal energy versus the square of the apparent discharge *** variation of voltage has no significant impact on the regression curve;that is,data from different voltages match one ***,when the distance between protrusion and plate is changed,the slope of the regression curve changes accordingly;the same energy corresponds to a bigger discharge *** results are significant enough to be applied in the estimation of the discharge quantity by measuring RF partial discharge signals.

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 is to calculate accurately the grounding performance of an unbounded grounding system under high-magnitude fault *** this work,a finite element model is presented to compute the characteristic parameters of the grounding system in frequency *** ionization phenomenon in the soil surrounding the grounding electrode is taken into account by setting the resistivity of every soil element while the resistivity of each element is varying with the electric field intensity;not a priori hypothesis on the geometrical shape of the ionized region around the electrodes has to be *** boundaries of the grounding system are represented by introducing a spatial transformation formulation,which translates the semi-infinite space into the finite space without shortening the domain as in the traditional *** suggested modeling is validated by comparison of the calculated results,which are laid out for grounding rod and grounding grid,with experimental and simulation results found in literature.

关键词： 局部放电   射频信号   放电量   高电压技术  

摘要： This paper presented a model to predict the AC flashover voltage of contaminated suspension *** prediction method is based on the maximum leakage current under AC operating *** kinds of widely used suspension insulators were tested in various contamination states such as pollution layers with different equivalent salt deposit density(ESDD),different composition of the conductive components,different non-soluble deposit density(NSDD) and different pollution distribution states to simulate the contamination states in *** effective ESDD was proposed and *** of contamination states to maximum leakage current and flashover voltage were ***,the relationships between flashover voltage and leakage current in these states were ***,considering the difference of insulator profiles,a new parameter is defined and a model to estimate the flashover voltage based on this parameter is *** model could be used in all kinds of suspension insulators in different contamination states and was validated by the test results.

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： Oil-paper insulation is used within most of high voltage direct current(HVDC) converter *** discharge(PD) in oil-paper insulation is a major reason for the development of internal faults in HVDC converter transformer,while PDs in oil-paper insulation mainly occur in terms of gas cavity *** are few study results on the development characteristics of partial discharges in oil-paper insulation and dissolved gases in oils of HVDC converter *** on a gas cavity discharge model of oil-paper insulation,the present study investigates the development characteristics of partial discharges under AC-DC combined voltages and emphatically examines the variation characteristics of dissolved gases in the discharge development *** and analysis results show that the characteristics of partial discharges and dissolved gases in oils under AC-DC combined voltages are appreciably different with those under AC *** results provide theoretical support for further research on partial discharges and on dissolved gases of other internal insulating defects and are helpful for the fault diagnosis of HVDC converter transformers.

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： In this paper,the DC flashover characteristics of iced insulator strings were explored in the multi-functional artificial climate chamber by four methods,namely,the average flashover voltage method,the minimum flashover voltage method(U-curve method),the maximum withstand method and the 50% withstand *** DC porcelain insulator strings and composite insulators were used as *** results indicate that the average flashover voltage and the minimum flashover voltage obtained by the average flashover voltage method and the minimum flashover voltage method,respectively,obey a normal *** 50% flashover voltage could be gained by the two methods with a minimal test number of nine and were about 8.0%~9.8% and 3.8%~5.9% respectively higher than that gained by the 50% withstand *** justified the feasibility of employing the Ucurve method and the average flashover voltage method to study the flashover characteristics of iced insulators and their affecting factors.

关键词： 高电压技术   课程改革   高职教育  

摘要： 针对高电压技术课程教学特点,结合高职教育人才培养要求,从教学内容、教学方法和考核方式等三方面提出改革思路,对高电压技术课程教学进行有益的探索和实践。

关键词： 高电压技术   专题征稿   组稿人   选题策划   国际化  

摘要： 组稿是编辑工作的重要环节,与稿件的质量及期刊的影响力密切相关,笔者列举了个别约稿、专题征稿、专家组稿、国际化组稿4种组稿方式,并结合《高电压技术》期刊的情况分别介绍了各种组稿方式的实现途径及注意事项。提出了组稿的3个注意事项,即做好组稿准备工作、定期联系作者和组稿专家、审核稿件。

关键词： 开关能力   验收规范   交流电流   交流开关   辅助电路   元部件   触点   连续性试验   定义   交货条件   设计   介质材料   尺寸选定   接地   接地开关   电气工程   电阻   电气安全性   频率   加热   高电压   高压电器   高电压技术   户内   绝缘水平   绝缘件   隔离开关   主电流   测量   测量技术   机器安全性   噪声电压   户外设施   使用条件   工作电流   操作频率   操作安全性   定单   户外   性能试验   合格试验   工作电压   额定电压   额定值   耐力   旋转式开关   常规检验   安全性工程   选择开关   分离   短路   短路电流   短时电流   启动电流   材料强度   开关   开关设备   接电装置   温度等级   温度测量   温升极限   温升试验   试验报告   试验   密封性   电压   电压测量   耐电压  

标准号: NF C64-471-102/A1-2012