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随着SF6气体绝缘设备在系统中的广泛应用,对其绝缘状态的监测、检验以及相应的缺陷类型识别,成为当前亟待解决的问题.通过建立缺陷模型,对SF6气体在不同状态下放电特性进行试验分析,得到了不同缺陷情况下SF6绝缘设备的放电类型特征参数,和特征气体组分.结果表明:典型特征气体可作为实际检测的比对标准,也可作为SF6气体绝缘设备故障诊断专家系统的数据资料. 相似文献
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文章首先论述了当前中压真空开关柜的发展的趋势及采用SF6气体绝缘的优越性。介绍世界各国开发SF6气体绝缘的真空开关柜的情况。最后提出我国今后发展SF6气体绝缘的真空开关柜具体措施的建议。 相似文献
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众所周知 ,SF6气体是一种无色无味无毒、不燃且不深于水的气体 ,具有优越的理化特性和电气特性 ,从上世纪 6 0年代开始 ,就成功地应用于各种开关设备中 ,作为绝缘和灭弧介质。经过几十年的发展 ,SF6气体绝缘开关柜已形成了一系列中高压成熟产品。在这里主要介绍一下这几年从国外新引进的 1 2kV~ 2 4kV的中压气体绝缘开关柜的一些特点。1 外形尺寸小 由于采用了SF6气体绝缘 ,柜体的体积大幅缩小。额定电压 2 4kV ,电流达到1 2 5 0A时 ,柜体的宽度才 6 0 0mm ,若电流在80 0A及以下时 ,柜体尺寸更是缩小到仅 40 0mm宽。这… 相似文献
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随着电力需求的增长和环境保护要求的提高,SF6气体的使用逐渐受到限制.SF6混合气体在一定程度上减少了SF6气体用量,目前已经在电气设备中应用.文中针对SF6混合气体在220 kV气体绝缘组合电器(GIS)中发生泄漏引起的绝缘变化展开研究,通过改变微量的气压值和混合比,探究混合气体的绝缘性能变化,分析气压、混合比因素对工频击穿电压的影响规律,获取各气压下各比例混合气体的绝缘强度曲线图,从而得到保证设备安全稳定运行的补气策略.研究发现,混合气体击穿电压的变化规律呈现出随着压强和混合比的提高,非线性程度增大的特点,并且得到了设备安全运行的混合比和气压的边界值.文中的研究可以为SF6/N2混合气体绝缘设备提供运维规程和技术标准,同时为制定混合气体的检测技术标准奠定基础. 相似文献
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本文介绍了500 kV主变压器差动保护动作的异常情况,现场检查发现5013 SF6气体绝缘电流互感器C相底座固定螺栓及接地连接处有过流痕迹,解体检查盆式绝缘子表面可见明显裂纹.对比故障相、正常相设备解体及盆式绝缘子射线层析检测结果,推断C相盆式绝缘子生产制造中存在杂质隐性缺陷,造成其局部内应力和电场不均匀,长期运行过程中,镶嵌件部位应力集中形成裂纹,逐步发生局部放电至贯穿性击穿,导致底座基础及接地螺栓处放电,主变差动保护动作.据此,提出增强盆式绝缘子入厂品控,加强同类型同批次设备巡视维护,严格落实运输要求等运检预防措施,以保障设备安全运行. 相似文献
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本文介绍了500 kV主变压器差动保护动作的异常情况,现场检查发现5013 SF6气体绝缘电流互感器C相底座固定螺栓及接地连接处有过流痕迹,解体检查盆式绝缘子表面可见明显裂纹.对比故障相、正常相设备解体及盆式绝缘子射线层析检测结果,推断C相盆式绝缘子生产制造中存在杂质隐性缺陷,造成其局部内应力和电场不均匀,长期运行过程中,镶嵌件部位应力集中形成裂纹,逐步发生局部放电至贯穿性击穿,导致底座基础及接地螺栓处放电,主变差动保护动作.据此,提出增强盆式绝缘子入厂品控,加强同类型同批次设备巡视维护,严格落实运输要求等运检预防措施,以保障设备安全运行. 相似文献
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介绍电气设备中SF6气体的管理方式,对SF6气体的温度、密度和压力管理提出建议,及SF6设备补充气和查漏方面应注意的问题. 相似文献
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Masaru Miyagawa Tetsuo Yoshida Nobuo Masaki Shiro Ohtake Iwao Ohshima 《Electrical Engineering in Japan》1991,111(7):60-67
Generally, it is known that insertion of a barrier under a nonuniform field in air increases the flashover voltage. This is called the barrier effect. However, there are many uncertainties that remain to be clarified about the barrier effect in SF6 gas. Therefore, the influence of the barrier shapes and positions on the flashover voltage for the lightning impulse voltages and voltages (50 Hz) is examined by inserting a barrier between a hemispheric-end rod and a plate in SF6 gas under near-atmospheric pressure. As a result, the following findings were obtained:. (1) Insertion of a disk-shaped barrier reduces the flashover voltage; a cup-shaped barrier whose surface curves almost along the equipotential line increased the flashover voltage by 30 to 40 percent;. (2) trapped charge on the barrier surface is of the same polarity as the applied voltage and the magnitude of positive charge was greater than that of negative charge. It was found also that there is a correlation between the amount of trapped charge and the flashover voltage; and. (3) application of a barrier under a nonuniform field in the atmospheric pressure SF6 gas helps reduce the size of, for example, a cubic-type gas-insulated switchgear. 相似文献
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Yulistya Negara Kohei Yaji Kiminobu Imasaka Noriyuki Hayashi Junya Suehiro Masanori Hara 《Dielectrics and Electrical Insulation, IEEE Transactions on》2007,14(1):91-100
This paper deals with AC particle-triggered corona discharge as a follow-up to our previous research with DC voltage to clarify the particle-triggered corona discharge process in SF6 gas. Corona current pulses, charges associated with a corona current pulse, and corona light pulses were observed with an aluminum ellipsoidal particle suspended in a parallel plane electrode system under a SF6 gas pressure range of 30 kPalesPles50 kPa by changing the particle position. Corona mode, phase (Phi)-charge (q) characteristics as well as corona discharge processes were discussed and the following results were obtained. AC corona mode depended on the instantaneous applied voltage, voltage gradient as well as the particle position and then, the Phi-q characteristics were also affected by those parameters. Charges flow into the floating particle due to coronas on the both tips of particle and excite field fluctuations around the opposite side of particle in addition to the applied AC field. The field fluctuation in SF6 gas by the corona charges was about 4% of the applied field and much lower than that in air gap which was about 70%. That is, the corona development was suppressed effectively by high electron affinity of SF6 gas even in the case of floating particle. The less effective interference between coronas on the both side of particle in SF6 gas results in an obscure local minimum in the breakdown voltage characteristics as the particle is in the vicinity of electrode as contrasted with a drastic fall in the breakdown voltage by the particle in air 相似文献
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通过阐述水分对SF6断路器的危害,分析SF6气体含水量原因以及水分含量与环境温度的关系,探讨断路器安装及运行过程中控制SF6气体水分含量的方法。 相似文献
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在分析了自能式与压气式SF6断路器分断过程中的不同状态后,论述了自能式SF6断路器压力特性的计算方法和过程,并以LW36-126为例,对计算的结果进行了分析与讨论。 相似文献
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