安装高度对瓷套式氧化锌避雷器电位分布影响的研究

安装高度对瓷套式氧化锌避雷器的电位分布有重要的影响。首先针对一500kV瓷外套式氧化锌避雷器,建立其有限元计算模型,分析了其最大持续运行电压条件下的电位分布,同时采用光纤-电流法完成了相关的实验,验证了计算方法的有效性。然后分析了安装高度对500kV、220kV、110kV瓷套式氧化锌避雷器电位分布的影响。发现:改变安装高度对110kV、220kV避雷器的电压分布影响较小,但是增大安装高度可使500kV上节和下节避雷器的电压分布系数趋于理想。     

1 100 kV GIS避雷器的研究

文章提出了1100kVGIS避雷器主体结构、电阻片、均压结构、壳体及运行监测等方面的总体设计思路,结合国内外1100kV交流系统过电压与绝缘水平的研究成果,确定了1100kVGIS避雷器的性能参数,提出了经验判据、内部电场、热稳定性及材料等方面的要求,论述了实现这些性能参数的思路和途径。并依据所确定的参数给出了1100kVGIS避雷器的外形尺寸图。     

用低压元件设计10000A冲击电流发生器

More and more applications of ZnO arrester in electrical system experienced more problems.One thing,that is still under some investigation,is the effect of multiple lightning strike to the performance of ZnO arrester.As we know,the design of ZnO arrester for transmission system and for distribution system differs in the point of view of the number of ZnO blocks.Transmission system,due to its higher nominal voltage than distribution system,has more numbers of ZnO blocks inside an arrester tube.In term of the current rating of an arrester,it is found that there is some different value of the current rating.The current rating of an arrester installed closer to electrical substation is higher than that of some further away from the substation.To the respond of a lightning impulse strike,the arrester will let a high value of impulse current flowing.It tends to heat the ZnO material of the arrester.If the number of impulse strike is quite high then it may give the effect to the change of the arrester performance.This condition will endanger the equipment that is protected by the arrester from lightning strikes.During this research,the scope of work is limited to making an impulse current generator toward to one having 8/20 μs wave-shape.This kind of impulse current wave-shape is the one that is used for studying the performance of ZnO block.The effect of the inductance and capacitance of the impulse current generator were also studied.A 10 fused cut out was blown by an impulse having 10321 A of 17.8/37.8 μs.A ZnO arrester block brokendown/allowed large value of current :10982 A flowing under the voltage of 10.5 kV     

110、220kV城网GIS中ZnO避雷器配置的研究

研究了110、220kV城网GIS中ZnO避雷器的配置和接线方式.结果表明:1)线路入口避雷器应布置在侵入波前沿,并采用V形连接.为此建议采用合成套ZnO避雷器悬挂在线路终端塔上.2)侵入波过电压水平随进出线电缆长度而变化的关系,因电压等级、网络结线、线路结构和参数的不同而差异较大,电缆末端及GIS是否需加装避雷器,宜通过数值计算和具体分析后确定.     

220kV氧化锌避雷器受潮诊断分析

氧化锌避雷器作为电气设备过电压保护设备,其性能的优劣对电气设备安全运行起着很大的作用。文章通过湖北咸宁供电公司塘角变电站一台220kV氧化锌避雷器受潮的诊断分析,说明氧化锌避雷器运行监视的重要性及其受潮后诊断分析方法。     

合成套氧化锌限压器的热特性研究──第二部分：阀片功率损耗的模型及限压器的热稳定性能

在工频电压作用下氧化锌阀片的功率损耗是温度与荷电率的复杂函数。本文从试验数据中得出了其人工神经网络模型，给出了合成套氧化锌限压器的热平衡图；分析讨论了限压器的稳定工作温度、极限工作温度和极限吸收能量；１１０ｋＶ、２２０ｋＶ合成套氧化锌限压器具有很好的热稳定性；同时讨论了阳光辐射对热稳定性能的影响。     

特高压并联电抗器中性点小电抗的过电压及绝缘水平分析

为了提高特高压输电系统的可靠性和安全性,利用EMTP建立了1000 kV典型输电系统的仿真模型.分别针对工频、操作和雷电过电压情况下中性点小电抗的过电压进行了计算分析,研究了并联电抗器和金属氧化物避雷器对过电压的抑制效果,重点分析了并联电抗器中性点小电抗的过电压,并对其绝缘水平进行了核算.实验发现:并联电抗器可有效抑制...     

500 kV瓷套式氧化锌避雷器电位分布的有限元分析与实验研究

荷电率是设计氧化锌避雷器的一项关键指标。针对一500 kV瓷外套式氧化锌避雷器,首先应用有限元方法,通过设置合理的计算边界来简化开域电场问题的求解,并采用耦合自由度的方法解决电位悬浮导体问题,计算了避雷器中的电位分布;接着在避雷器最大持续运行电压下,采用光纤-电流法,通过测量避雷器中电阻片的轴向电压分布,验证了计算方法的正确性和有效性;然后分析了计算边界大小、均压环参数、安装高度等对电位分布的影响。发现:增大安装高度,可使上节和下节MOA的电压分布系数趋于理想;下均压环对改善电位分布的作用最为显著。     

氧化锌避雷器现状及存在问题分析

介绍了国内外氧化锌（ZnO）非线性电阻片技术的发展过程和改良成果。以及氧化锌避雷器（MOA）的工作原理、结构和特性参数。结合广东电网公司揭阳供电局220kV普宁变电站的MOA故障案例进行分析,指出MOA在过电压防护、密封材料老化、绝缘套污染等方面还存在问题．认为选择MOA主要控制2个方面：必要的过电压保护水平和足够的使用寿命。     

一起110kV母线避雷器泄漏电流超标的原因分析

某220kV变电站雷雨后,巡视发现110kV北母B相避雷器泄漏电流超标,通过用红外线成像仪测温中发现内部发热缺陷,分析为避雷器顶部密封不良,进水受潮,引起氧化锌阀片绝缘下降,及时进行了停电处理;停电后进一步进行高压试验测试,发现B相避雷器泄漏电流值过大,认定内部绝缘有局部击穿现象,故更换了B相避雷器,检查其它两相正常后,投入了运行,避免了一次110kV母线事故的发生。     

1 000 kV交流特高压GIS型和瓷套型金属氧化物避雷器的研发

文章较详细地介绍了1000kV交流特高压试验示范工程用GIS型和瓷套型金属氧化物避雷器（简称避雷器）产品的主要技术参数及廊坊电科院东芝避雷器有限公司对1000kV交流特高压避雷器的研发实绩。大容量电阻片、GIS型避雷器和瓷套型避雷器的研发工作都是在株式会社东芝相关技术的基础上进行的。大容量电阻片完全满足特高压GIS型和瓷套型避雷器要求，具有足够裕度，并已实际应用于500kV和750kV瓷套型避雷器。GIS型避雷器的电位分布解析结果与日本新榛名变电站使用避雷器的解析和实测结果都相当一致，满足技术协议要求。瓷套型避雷器属国际首创产品，应用了4项株式会社东芝具有实际运行业绩的关键技术，特别是减震技术（装置）大幅度减小了瓷套根部应力，从而满足抗震要求。最后初步探讨了试验的可行性和等价性．并给出相关建议。     

A Procedure for Estimating the Lifetime of Gapless Metal Oxide Surge Arresters for AC Application

The development of the gapless metal oxide (ZnO) surge arrester has presented the arrester engineer with new materials and an opportunity for new designs. This situation arises because the gapless surge arrester is electrically active throughout its lifetime whereas its predecessor, the silicon carbide arrester, was electrically passive being electrically isolated with gap structures. The prime consideration is one of reliably estimating the lifetime of a gapless ZnO surge arrester under continuous ac stress while maintaining the capability not only to limit surge voltages but also to absorb energy inputs resulting from lightning or switching surges and temporary overvoltages. In this paper we establish a procedure for reliably estimating the lifetime of gapless metal oxide surge arresters for ac application by incorporating the device characteristics into design requirements. This method is illustrated for metal oxide surge arrester elements that exhibit a predictable linear resistive current versus time1/2 behavior as a function of applied voltage and temperature.     

金属氧化物避雷器现状及发展趋势

文章介绍了国内外氧化锌（ZnO）非线性电阻片技术的发展过程及改良成果；避雷器电场设计技术的变迁，三维电场解析软件在避雷器设计中的应用；瓷套型避雷器、GIS型避雷器、复合外套型避雷器的技术进步；以及伴随ZnO电阻片性能的提高所带来的避雷器小型化、轻型化、高可靠性和长寿命。文章最后还介绍了IEC标准制定各个阶段的讨论重心、成果以及今后要解决的课题。     

Development of a detection device for deteriorated ZnO surge arresters at AC traction substations

This paper presents a novel detection device for deteriorated zinc‐oxide (ZnO) surge arresters. It is necessary to understand the state of ZnO surge arresters for AC traction substations under operation. The waveform distortion of leakage currents can be detected through an increase in multiple harmonic currents; therefore, this effect was employed to develop a device for diagnosing damage to the surge arrester. By adopting a Rogowski coil and band‐pass filters, we can obtain more output of the 5th–15th order harmonic currents in comparison with conventional devices. If the threshold value of harmonic elements is exceeded, the lights on the device may light up to indicate the deterioration. The validity of the device was verified by artificial deterioration tests using damaged ZnO elements and a capacitor. This developed device could indicate the soundness of the surge arresters that are in proper working order while being under the influence of feeding voltages, which include harmonic voltages.     

Pressure Relief Design and Performance of Metal Oxide Surge Arresters

Surge arresters with porcelain housing must not have explosive breakage of the housing to minimize damage to other equipment when subjected to internal high short circuit currents. Also, arrester porcelain housings are generally susceptible to undesirable thermal shock. As a solution, this paper describes pressure relief design and performance of arresters equipped with a fiber reinforced plastic tube and an optimum pressure relief nozzle. The arresters showed satisfactory performance during a newly developed synthetic pressure relief test using a 25 kA symmetrical rms current with the first half-cycle fully offset.     

特高压避雷器用ZnO压敏电阻电压梯度限值的探讨

为了研制性能优异的特高压避雷器,笔者对实际所需ZnO压敏电阻的电压梯度是否存在限值进行了研究,并结合特高压避雷器的实际应用需求,详细讨论了ZnO压敏电阻的电压梯度限值的相关问题。研究表明,对适用于特高压避雷器的ZnO阀片,其电压梯度不仅受到特高压避雷器绝缘间距、通流容量等外在因素的限制,同时也受到ZnO阀片能量吸收密度的限制。在现有生产制造能力的条件下,特高压避雷器采用ZnO阀片的电压梯度越高,阀片所必须达到的能量吸收密度也越高。笔者通过理论分析与计算得出,特高压避雷器适用ZnO阀片的方波能量吸收密度理论极限值为517 J/cm3,对应的电压梯度理论极限值为686 V/mm。对于特高压瓷套、复合外套、GIS罐式避雷器所需ZnO阀片,最理想的电压梯度分别为213、300、426 V/mm,相应的能量吸收密度要求至少分别为150、226、301 J/cm3。     

Development of 1100 kV a.c. high-performance GIS-arrester and its verification tests

For the purpose of realizing 1100 kV a.c. power transmission system to meet the demands for electricity in future Japan, the 1100 kV a.c. high performance gas-insulated metal enclosed arrester (GIS-arrester) was developed and its high reliability was confirmed by a long-term performance verification test. The high-peformance GIS-arrester is a key component to determine the insulation level of 1100 kV a.c. power transmission systems and substation equipments. As part of a series of activities started around 1975 by the Special Committee on 1100 kV a.c. Power-Transmission system, the high-performance GIS-arrester with the superior protective performance of the world highest level was developed by applying the ZnO elements developed and commercialized in Japan. This paper introduces the application effects, duties, specifications, progress of development, and results of verification tests for the high-performance GIS-arresters for 1100 kV a.c. power transmission system. Copyright © 2009 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

光伏变电站用氧化锌避雷器多物理场耦合分析

针对传统有限元法在多物理场耦合计算过程中存在计算量大、精度过于依赖网格划分的缺陷,以某光伏变电站用220 kV氧化锌避雷器为例,提出一种将有限元法与无网格法结合的温升计算方法。首先,建立了避雷器三维流体场有限元模型,得到流体分布;其次,将对流换热系数作为温度场计算的边界条件,分别采用有限元和无网格法计算额定运行下避雷器温升和避雷器老化故障情况下的温升;最后,与基于传统有限元法耦合计算及实验结果进行对比,在验证了所提方法准确性的同时,还发现其求解速度远高于传统有限元法。     

光伏变电站用氧化锌避雷器多物理场耦合分析

针对传统有限元法在多物理场耦合计算过程中存在计算量大、精度过于依赖网格划分的缺陷,以某光伏变电站用220 kV氧化锌避雷器为例,提出一种将有限元法与无网格法结合的温升计算方法。首先,建立了避雷器三维流体场有限元模型,得到流体分布;其次,将对流换热系数作为温度场计算的边界条件,分别采用有限元和无网格法计算额定运行下避雷器温升和避雷器老化故障情况下的温升;最后,与基于传统有限元法耦合计算及实验结果进行对比,在验证了所提方法准确性的同时,还发现其求解速度远高于传统有限元法。     

用EMTP程序计算500kV串补输电线路的操作过电压

本文用EMTP程序计算了500kV串补输电线路的操作过电压,分析计算了故障地点不同、串补度不同、加装500kV氧化锌避雷器和有、无合闸电阻的情况下串补电容对操作过电压的影响,还校验了避雷器的通流容量;构成了氧化锌非线性电阻的伏安特性曲线,本文提出了限制输电线路操作过电压的措施.