绝缘击穿是并联电容器单元最常见的故障形式,但目前没有成熟的方法监测其绝缘故障发展过程,故障发生后往往无法准确判断故障原因,从而导致相同的故障重复发生.本文首先分析了电容器元件击穿过程的电压和电流变化规律,据此提出了一种电容器元件击穿故障监测方法,并开发了监测设备,监测装置成功记录到了多次故障波形.本文对记录到的元件击穿和外熔断器缺陷这两种典型故障波形进行了详细分析,证明了理论分析和实际故障录波的结果是一致的,验证了本文提出的监测方法能够判断出电容器单元的故障类型并分析出故障原因,为故障判定和预防提供了有力的数据支撑.

纳米复合材料具有成为高储能密度电介质的潜质,在脉冲和储能领域拥有巨大应用潜力,为此利用XRD、DSC和介电谱对BaTiO3/α-PVDF、BaTiO3/γ--PVDF复合介质的基体结晶情况和介电特性进行了分析.在室温0.1Hz条件下,BaTiO3体积分数为10％的BaTiO3/α-PVDF介质相对介电常数为30,BaTiO3体积分数为10％的BaTiO3/γ-PVDF介质相对介电常数达52,γ相复合介质介电常数要越高于α复合介质,说明在低填充量下BaTiO3/PVDF复合介质中基体晶形特性将对Maxwell-Wagner极化强度起主要作用,并利用一维结晶分布模型对复合介质中界面密度进行表征,结合复合介质损耗峰的位置,发现界面密度与Maxwell-Wagner界面极化松弛时间存在明显负相关性,为利用Maxwell-Wagner极化调节纳米复合电介质的低频介电特性提供了方法.

Polypropylene film is used widely solid insulation and monobenzyltoluene as liquid insulation between the poles of high voltage power capacitor and performance of the power capacitor is therefore improved greatly.However, such faults as oil leakage and moisture are inevitably occurred due to a large number of capacitors in operation.The capacitor, in this case, must not have expansion failure.Therefore, the insulation performance of the insulation between poles under the moisture condition is of great importance for safe operation of power capacitor.In this paper, the insulation strength of natural damped capacitor element is obtained by way of natural moisture of the power capacitor, the withstanding performance of the insulation between poles of high voltage capacitor is judged by such data so to provide reference for the manufacture and operation of powercapacitor.

复合绝缘具有重量轻、机械强度大的特点,采用复合绝缘的线路避雷器被广泛用于提高输电线路的耐雷水平,降低雷击跳闸率.然而,复合护套的硅橡胶材料长期运行于户外环境中,一旦材料特性不佳,将容易老化甚至造成其发生闪络.分析了一起运行10年的复合绝缘线路避雷器因外护套老化而发生沿面闪络的故障,经过交直流耐压及局放试验研究后,将故障避雷器进行了解体,并对外护套进行了理化实验、硬度试验、电镜试验、户外暴晒场试验.结果 发现其故障原因是硅橡胶绝缘老化和硅橡胶同玻璃钢材料的界面结合不佳,造成憎水性消失和局部放电所致.通过分析,给出了复合绝缘线路避雷器的相关运行建议.

This paper briefly introduces the general situation of UHV AC project in China,the parameters and configuration of 110 kV side shunt capacitor device,as well as the installation and arrangement of the capacitor bank.On the basis of this,the paper presents a 110 kV shunt capacitor device to meet the paral-lel compensation of 1 000 kV UHV AC project.This paper also expounds the superiority of the device to be used in the limited area and with high seismic requirements.The research situation of 110 kV shunt capaci-tor is introduced in detail.

为了获得1.2倍额定电压、环温55℃运行工况下集合式并联电容器内部温度分布,本文运用有限体积法,以集合式并联电容器BAMH126.3/3-80000-1W为研究对象,根据实际真实电容器尺寸,用流体力学仿真软件Fluent建立其三维温度场仿真模型,对其温度分布进行仿真.得到了其整体内部温度场分布,仿真结果表明,集合式并联电容器内部温度由底部至顶部呈上升趋势,且最热点温度位于顶层心子内部,变压器油温度最高点位于散热器顶部,最低点位于散热器底部,为集合式并联电容器散热结构优化设计和内部温度最热点控制提供参考.

为了获得1.2倍额定电压、环温55℃运行工况下高压全膜电容器内部温度场分布,分析了高压全膜电容器内部结构,建立了高压全膜电容器三维温度场仿真模型,并基于ANSYS Fluent进行求解,得到高压全膜电容器整体温度场分布,仿真结果表明:电容器外壳由头部至尾部温度逐渐升高,外壳顶部温度高于底部,侧卧时心子最热点集中在心子尾段,立放时心子最热点集中在心子中段.

我国全膜高压并联补偿电容器经过20年的普及使用,不论是生产厂家还是用户均有人提出:当年由全国无功补偿装置专家工作组确定的全膜电容器设计场强不宜大于57 kV/mm(k=1)的指标不适用了,应提高电容器设计场强.经对我国主导生产厂家的三膜结构并联电容器绝缘耐受水平的研究,得出专家工作组的这一规定对我国全膜高压并联电容器健康快速发展起到了十分关键的作用,进一步提高设计场强应谨慎,应在进行充分研究的基础上再做提高设计场强变更,否则对产品的运行可靠性是不利的.

Because of the large capacity and compact structure of the UHV compact shunt capacitor, it is difficult to take effective measures to detect and prevent the faults. If the fault capacitor fails to take timely maintenance, it will pose a threat to the safe operation of the system and the life safety of the maintenance personnel. The development of UHV compact shunt capacitor on-line monitoring system can detect and record the on-line operation information of UHV compact shunt capacitors, analyze and evaluate the early fault warning signs, find out the fault capacitor or the capacitor with fault symptom, to ensure safe and reliable operation of the system.

随着人们对环境保护的关注,近年来电力系统对换流站滤波电容器噪声问题日益重视.当前,国内关于电力电容器的噪声试验的标准有2个,分别是GB/T 28543-2012《电力电容器噪声测量方法》和GB/T 32524-2016《声学声压法测定电力电容器的单元的声功率及和指向特性》,2个标准在噪声测点位置布置、测量面的选择等方面存在一定的差异.本文采用理论分析和试验验证的方法对此展开研究,希望给出一个较合理的电力电容器噪声试验方法,供科研单位及厂家参考.

干式空心电抗器是电力系统中比较重要的电力设备,主要用于限制短路电流以及无功补偿,因此电抗器能否保持稳定运行关系着电网整体的安全稳定.在我国北方地区,冬天气候寒冷.北方地区冬天经常发生电抗器烧毁事故,尤其是当电抗器进行合闸操作的时候.因此为了探索低温环境对干式空心电抗器绕组性能的影响,本文对绕组部分不同低温环境下的绝缘特性和机械特性进行了研究.

为了获得特高压用并联电容器在运行工况下的温度场分布,文中在ANSYS Workbench 15.0环境下采用流—固—热耦合场建立了特高压工程用并联电容器在侧卧情况下的三维温度场计算模型,在Fluent 15.0中采用有限体积法计算了该模型,获得了电容器外壳和心子的整体和各面的温度分布云图并进行了系统地比较和分析.结果表明:从总的趋势来看,电容器顶面温度高于底面和侧面温度,电容器外壳最热点位于在电容器顶面上.心子侧面温度高于顶面和底面,圆弧处温度低于元件其他部分.电容器内部最高温度近似在靠近中轴线和尾部的某处.根据计算结果可为电容器运行提供参考也为后续高压并联电容器内部最热点温度的估算提供了潜在方法.

高介电常数材料在未喷涂电极前,如何测准他的介电常数,以判断该材料质量是否满足要求是一个困难.本文介绍一种通过恒压力电极,对给定的高介电常数材料在该电极下产生的气隙厚度进行计算,并利用该气隙厚度对所测到的电容量测量值进行校核,得到该批材料较准确的介电常数值,以对该批材料质量进行评判,从而避免生产中不必要的人力、物力和财力的浪费.

温度是影响电容器运行性能及寿命的关键因素,为了获得集合式并联电容器内部的温度场分布,论文分析了集合式并联电容器内部结构及热量的产生和散失机理,在ANSYS Workbench 15.0中建立了集合式并联电容器温度场三维仿真模型,并利用有限体积法进行了求解,得到了集合式并联电容器的内部温度场分布、外壳温度和最热点温度,仿真结果及方法可以为集合式并联电容器散热结构的优化设计及内部最热点温度的控制提供参考.

In this paper, the internal fuse of shunt capacitor which was BAM6.56-556-1W used in AC UHV project had been designed and calculated.Combined with the method of energy calculation and fuse current density, and the internal fuse model withΦ0.42 ×160mm was chosen.In order to test the performance of the internal fuse, based on the improvement of the internal fuse parameter, the test sample capacitor was designed and tested according to experi-mental plan which was stricter than GB/T 11024.1-2010, GB/T 11024.1-2001, DL/T840-2003, et al.The result indicated that the revised-design internal fuse which was used in BAM6.56-556-1W sample capacitor had passed all verification test items.Compared with the requirement of standard, the short-circuit discharging voltage was increasing by 30%, the upper limit voltage of fuse insulating test was increasing by 30%, the range of lower limit voltage was in-creasing 10%, and the withstanding voltage of the fuse fracture was increasing 30%.The internal fuse which was ver-ified by test was helpful for the safe and reliable operation of the shunt capacitor installation used in AC UHV project.

集合式电容器自1985年投运以来,因接线简单、占地面积小、运行可靠而发展迅猛,到上世纪末,集合式电容器达到发展的顶峰,此时市场占有率达到了45％左右.但随着全膜绝缘技术的发展,集合式电容器占地小的优势逐步减小,而运行可靠性不高的问题越来越突出,这导致集合式电容器的市场占有率减小到20％左右.因此,集合式电容器发展到今天,已面临下一步发展方向如何确定的问题.文章就此谈了作者的观点,以供读者参考.

为了防止变压器突发性恶性事故发生,探寻更为准确地评估超高压变压器油纸绝缘老化状态和预测变压器剩余寿命的方法意义重大。为此,在130℃下进行了变压器油纸绝缘加速热老化实验,同时跟踪测定变压器油中的酸值、糠醛含量和介质损耗因数,分析模拟老化条件下生成酸类物质的规律,并与变压器老化特征量糠醛和油介质损耗因数的变化规律进行了对比分析。实验结果表明:在变压器油纸绝缘热老化过程中,老化生成酸性物质的反应分为反应诱导阶段和反应发展阶段。在老化反应进入诱导阶段后期,油中糠醛的含量下降,此后,油中的糠醛含量便不能正确反映变压器纸绝缘的老化状况。在老化反应的发展阶段,其反应速率常数是诱导阶段的约5~11倍。老化过程中变压器油中酸值的变化和介质损耗因数的变化具有良好的相关性,生成酸类物质反应速率的快速增加,与变压器油的绝缘性快速下降相一致。结果初步表明跟踪测定变压器老化过程油中酸值的变化,可更为准确地评估变压器油纸绝缘的老化。

With the widespread use of capacitor voltage transformer ( CVT) in power system, there exist a few prob-lems, among which internal capacitance component breakdown failure is one of common problems.Now a large num-ber of CVT on-line monitoring systems need to add primary hardware equipment, which would not only increase the investment, but also might affect the system security.This paper used CVT secondary voltage data in EMS( energy management system) inform the steady operation in Guangdong power grid corporation, and researched on the relation-ship between CVT self-state and secondary voltage, then determined threshold of fault diagnosis through combination of theoretic calculation and statistical analysis, and in the end it established CVT on-line monitoring system without addition of primary system hardware equipment.This system could prevent fault deterioration and threaten safety of system, so as to achieve the goal of increasing power system stability.

钛酸钡因具有高介电常数、压电铁电性及正温度系数等优异性能而成为重要的陶瓷材料。烧结工艺对钛酸钡陶瓷的致密化与显微结构具有重要影响;钛酸钡陶瓷存在介电常数随温度的变化率较大、介电损耗高、击穿场强低、本身存在薄层时吸收强度弱和带宽窄等缺点,常常通过掺杂改性来提高钛酸钡陶瓷的性能,而不同掺杂材料对钛酸钡陶瓷的影响各异。综述了近年来高性能钛酸钡陶瓷烧结工艺和掺杂工艺的研究进展,总结了各自的主要特点,并列举了钛酸钡陶瓷的主要应用场合。钛酸钡陶瓷应用前景广阔,进一步研究更优良的钛酸钡陶瓷烧结工艺及掺杂工艺意义重大。

In this paper, the loss and overvoltage of capacitor unit for differential protection wiring, which is launched recently for 10 kV frame type shunt capacitor devices, is simply calculated and analyzed, and it is concluded that inside the capacitor unit, used in this device, only two serial section, high current of capacitor in normal operation, additional loss increase, heating problems easy to appear. In case of capacitor failure, overvoltage transmission is easily happened. The capacitor and the intact series section are damaged by heating of capacitor and its connectors as well as overvoltage transmission, which will bring hidden danger for operation. Therefore,such wiring at 10 kV frame type capacitor type shall be used as less as possible so to avoid fault development of capacitor device endanger safety of power system.