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《高电压技术》2016,(11)
为了同时实现对雷电流的测量和定位功能,研制了一种新颖的雷电流测量传感器。基于雷电流引发的空间磁场原理,对传感器线圈的物理模型、几何参数、生产制造工艺等进行了详细研究,研制了相应的线圈。通过试验验证了该传感器线圈实测参数与理论设计参数的一致性及其雷电流响应特性。试验结果表明:线圈参数误差在可接受范围之内;幅值与频率响应特性良好,可以满足雷电流测量需求;线圈输出电压与雷电流幅值呈线性关系,与测量距离呈二次反比关系,与理论一致。通过试验标定了该传感器线圈的灵敏度,获得了传感器线圈输出电压幅值与雷电流幅值及测量距离的关系表达式,为现场应用提供了重要的理论和试验依据。 相似文献
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变压器分接开关出现故障甚至烧蚀时会影响变压器绕组的频率响应特性。利用频率响应分析法对某变压器进行绕组变形测试,分析了分接开关烧蚀对绕组变形测试结果的影响。在Matlab仿真平台上建立了分接开关烧蚀时的绕组等效模型,利用计算机仿真研究了分接开关烧蚀时在不同频率范围内对绕组变形结果的影响程度,为今后分析变压器绕组变形频率响应曲线提供了理论分析手段。 相似文献
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检测GIS局部放电的内置传感器的模型及性能研究 总被引:23,自引:7,他引:23
全封闭组合电器(GIS)局部放电检测对于保证其安全可靠运行具有重要的意义。该文从电气测试的角度,研究了GIS局部放电信号的内置传感检测,研制了圆板型和圆环型两种内置传感器,采用电容耦合模型和天线模型研究了这两种传感器的性能。GIS局部放电实测结果表明,文中所研制的内置传感器性能优异,能够传感纳秒级的局部放电脉冲信号,频率响应特性好,完全能够满足GIS局部放电信号测量要求,圆环传感器的灵敏度高于圆板传感器。 相似文献
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含风电的电力系统动态频率响应快速评估方法 总被引:2,自引:0,他引:2
大规模随机波动的风电功率接入电网引起系统频率偏差,从而影响系统安全稳定运行。为了研究不同频率风电功率波动对系统频率偏差的影响,提出了考虑发电机特性、调速器特性、系统网络结构、负荷特性,含风电的电力系统频率响应频域分析模型。基于该模型推导了风电功率激励下的电力系统各节点频率响应传递函数的显式表达式。根据传递函数的幅频特性能准确反映不同频率风电功率波动激励下各节点的频率响应特性。将该模型应用于IEEE 10机39节点系统,结合实测风电场功率波动数据进行了算例仿真,结果表明利用该模型能快速准确评估风电功率对系统各节点频率响应的影响。 相似文献
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GIS局部放电超高频检测法有关问题的仿真研究 总被引:7,自引:6,他引:7
气体绝缘组合电器(gas insulated switchgear,GIS)中的局部放电在腔体中产生超高频(ultra high frequency,UHF)电磁波信号。为研究GIS局部放电源与UHF信号的关系,利用时域有限差分法计算局部放电产生的UHF信号;通过改变放电源和探头的参数,研究了局部放电产生的UHF信号的特性。仿真分析结果表明:UHF信号的幅值与局部放电脉冲幅值成线性关系;UHF信号与放电源的径向位置、放电通道长度、放电脉冲波形以及放电源与探头的夹角有关。单纯 UHF信号很难解释局部放电量的大小,但UHF信号可在一定程度上反映出GIS的绝缘状态。 相似文献
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GIS中电磁波传播特性的仿真研究 总被引:8,自引:2,他引:8
为研究UHF信号在GIS中的传播特性,采用时域有限差分法进行了仿真建模和计算。GIS内部的局部放电会在腔体中激励超高频(UHF)电磁波信号,UHF法是通过对局部放电时产生的超高频电磁波信号进行检测,获得局部放电信号的有关信息以实现对设备的绝缘状态诊断和评估。UHF法抗干扰能力较强、灵敏度高。仿真结果表明,UHF信号在GIS内传播时呈现明显的时延特性,有利于局放源的定位;UHF信号的强弱和检测点与局放源的夹角Φ有关,Φ=0°和180°时信号的能量最大;局放脉冲越陡,在GIS腔体中激励的高次模波分量越大。 相似文献
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用超高频局部放电测量法实现电力变压器局部放电的在线监测 总被引:1,自引:0,他引:1
高频局部放电测量法(UHF法)与传统的脉冲电流法完全不同,它采集的被测信号为局部放电过程所产生的超高频电磁波:利用UHF法可有效解决电力变压器局部放电在线监测中的抗干扰问题。文中结合变压器结构设计的放油阀式和人孔/手孔盖式超高频信号传感器安装在220kV和110kV电压等级变压器上,成功地捕捉到变压器内部局部放电产生的超高频信号。对变压器局部放电故障诊断的判据等问题进行讨论,为变压器超高频局部放电在线监测方法的应用积累了经验。 相似文献
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《Dielectrics and Electrical Insulation, IEEE Transactions on》2008,15(6):1544-1552
The paper provides essentially a summary of PD measurements applying the UHF range in order to increase the detection threshold, to improve the localization accuracy and to perform on-line measurements of Partial Discharge (PD) in noisy environments. The electromagnetic UHF technique offers good signal to noise ratios, because external PD signals and disturbances can be shielded effectively. A new developed method allows the localization of PD in gas-insulated substations (GIS) by frequency domain measurements. The basic idea is the displacement law of Fourier transformation. The interference phenomena of superposed signals from two sensors give information about the time delay of the sensor signals. On-site PD measurements are made at cable connectors by means of monopole antennas housed in a barrel sleave, while the cable is in service. Thus a sensitive PD measurement even in noisy environment is possible. PDmeasurements on several 72 kV cable connectors were performed in an unshielded laboratory. On-site measurements during operation showed the great potential for condition assessment. For decoupling sensitive UHF PD signals from the inner of a power transformer tank UHF sensors applied through drain/oil valves are used. Experimental studies indicate that all relevant types of PD possibly occurring within a transformer emit high frequency spectra to be detected with UHF sensors. Furthermore in laboratory experiments and on-site measurements very moderate UHF signal attenuations have been observed. 相似文献
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Chang C. Chang C.S. Jin J. Hoshino T. Hanai M. Kobayashi N. 《Power Delivery, IEEE Transactions on》2004,19(4):1579-1586
With increasing interest in the reduction of cost for operation and maintenance of SF/sub 6/ gas-insulated switchgear (GIS), various methods of condition monitoring have been developed and used in conjunction with highly sensitive sensors and advanced digital signal processing techniques. Detection of partial-discharge signals in GIS using ultra-high frequency (UHF) technique has gained wide acceptance in research and industry. Unlike approaches of fast Fourier transformation and discrete wavelet transformation (DWT), a novel method of using an adaptive linear combiner as a prediction model to analyze UHF signals is introduced in this paper. Successful results are obtained by applying this new method on field data measured by a UHF coupler. The feasibility of this new approach is studied and proved by the statistical distributions of the trained weights. 相似文献