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分析了雷击浪涌进入变电站二次设备的途径,对比了常用的浪涌保护器(SPD,Surge Protective Device)的浪涌骚扰抑制特性,如响应时间、残压水平、浪涌峰值电流、寿命等,然后对微机保护设备的各个端口进行浪涌响应特性试验.最终的结论是,根据IEC标准,各个端口施加的浪涌电压水平及源阻抗不同,而且端口电路的响应也不同,所以各个端口所需要的浪涌防护也是不同的. 相似文献
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SPD(surge protective device)中文名为电涌保护器,亦称为浪涌保护器。SPD至少包含一个非线性电压限制元件,用于限制暂态过电压和分流电涌电流。按照电涌保护器的功能,可分为电源电涌保护器、天馈电涌保护器和信号电涌保护器。 相似文献
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线路电阻对SPD配合的影响分析 总被引:2,自引:1,他引:1
为了准确分析用于低压配电系统过电压防护的多级浪涌保护器(SPD)的配合问题,通过建立SPD配合电路的拉氏运算方程,求解并分析线路电压降的解析解,理论研究了线路电阻对低压系统SPD配合的影响,指出忽略线路电阻将使通过后级SPD的电流被夸大,造成配合分析的不准确。理论分析表明,在前级SPD的残压一定的情况下,2级SPD间的电压差主要由后级SPD的V-I特性曲线、线路电感和线路电阻共同决定。通过对多种线路模型的SPD配合进行仿真计算,验证了理论分析的正确性。 相似文献
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电子信息系统防雷工程中对浪涌保护器的选择和应用 总被引:2,自引:0,他引:2
为防护雷击电磁脉冲(电涌)对电子信息系统造成干扰破坏,介绍了在防雷设计中如何选择浪涌保护器(SPD)。对浪涌保护器的原理、技术参数、安装及级间耦合等进行分析。提出了在具体防雷方案设计中应注意的若干问题,及在选择使用浪涌保护器时涉及的几个主要步骤。指出合理选用浪涌保护器可有效降低雷击风险,避免雷电灾害。 相似文献
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谈到SPD的问题,首先要从定义上来看。GB18802.1—2002中已明确了低压配电系统中电涌保护器的用途。电涌保护器就是用于限制瞬时过电压和限放电涌电流的电器,至少包含一个非线性元件。然后,要看功能。电压开关型电涌保护器,即没有电涌电流时具有高阻抗,有浪涌电压时能立即转变成 相似文献
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This paper provides circuit models for analyzing the coordination between primary and secondary surge protectors. Although the analysis is performed in the context of lightning surges on telecommunication circuits, the models developed are generic in nature and can be used to analyze the interaction of cascaded surge protectors under voltages produced either by lightning or by power line disturbances. Equivalent circuits are developed for calculation of voltages and currents at primary and secondary protectors. Formulas are provided and procedures are described for achieving the best coordination between primary and secondary protectors. Two different configurations are analyzed for protection coordination. In the first configuration, the primary and secondary protectors connect between each conductor of the cable pair to ground. In the second configuration, a secondary protector is located between two conductors of a cable pair while the primary protector is located from each conductor to ground 相似文献
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针对低压电源感应雷电,采用电涌保护器进行防护已是目前普遍采用的方法。从低压电源系统故障、防雷器件特性、防雷标准、防雷产品、试验检测等方面,对电源类电涌保护器进行了相关论述。指出电涌保护器工作在低压电源系统中,在考虑雷电防护能力的同时,也必须关注产品的安全性。 相似文献
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微电子电路常因过电压损坏 ,其过电压保护与电气设备相比有不同的要求 ,因此文中介绍了过电压对微电子电路的侵入方式 ,测试了常用防雷元件的动作时延及其伏 -安特性 ,给出了防雷元件的电容对数字通信信号影响的计算公式。实测表明动作时延太长不能保护微电子电路 ,防雷元件的电容大于一定值后会使通信信号发生畸变 ,致使误码 相似文献
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变电站微机保护和监控系统电源干扰及抑制 总被引:2,自引:1,他引:1
雷击浪涌是低压电源线中发生最频繁的干扰源之一。为研究雷击浪涌对变电站微机保护和监控系统电源的干扰,首先通过分析电源线中雷击浪涌的入侵途径,提出了雷击浪涌危害的主要原因。然后基于过电压保护和电磁兼容两个方面的考虑,提出了低压电源线及低压电子设备的保护措施:一方面,根据低压电源系统防雷保护存在的问题,提出了完善低压电源系统的保护措施;另一方面,根据雷击浪涌的频谱中包含低频能量和高频能量的这一特征,提出了将瞬态抑制与滤波技术相结合的措施,即采用压敏电阻(MOV)消除低频能量,采用L-C低通滤波器滤除高频能量,从而有效地抑制雷击浪涌干扰。 相似文献
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气体放电管(GDT)是开关型电涌保护器的关键元件之一,去年国际电工委员会(IEC)发布了GDT的新标准,全面阐述了应用于低压电涌保护器的GDT的性能要求、测试方法、选择及其应用原则。通过对新标准的解读,并结合防雷工程实践,进一步提高对GDT在低压电涌保护器应用过程中的安全性和可靠性的认识。 相似文献
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基于人工触发闪电T179的10次回击过程,分析了雷电流作用下2个独立地网的相互作用及转移地电位特征,并通过冲击低压电源浪涌保护器(SPD),计算和评估了转移地电位冲击SPD的能量。结果发现,地网隔离40 m距离产生的转移电位(TGP)电压峰值比较大,平均值可达–10.9 kV。TGP电压峰值与触发闪电电流峰值之间呈现非常好的正相关性,拟合优度R2达到0.97。冲击SPD的能量比较小,10次回击平均值为1.5 J,电子设备加装SPD浪涌保护器是相对安全。 相似文献
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Wherever lightning and poor utility power system grounds exist, distribution secondary systems are subjected to high-voltage surges due to lightning current seeking ground through low-voltage circuits. Utilities are becoming aware of this low-side surge phenomena and are taking measures to protect their distribution transformers' secondary windings. These measures can increase the voltage stress at the customer service entrance. If any ground paths exist on the customer side of the service entrance, surges can penetrate further into the customer's system and damage loads. Damage caused by low-side surges can be avoided if properly coordinated arresters are installed at the transformer secondary, at the service entrance, and at load devices. This work describes the secondary surge phenomena and the importance of protecting the service entrance and critical load devices effectively, especially when the transformer secondary is protected. A properly coordinated and effective protection scheme is described and recommended 相似文献
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低压电涌保护器的发展动向 总被引:1,自引:0,他引:1
对低压配电系统电涌保护器(过电压保护器)的发展动向作了分析,并着重介绍其国际标准、产品发展动向和生产水平以及研究方向.于2005年通过的IEC61643-1A2版本在标准协调性、安全性、可靠性、合理性和可操作性等方面均有显著提高. 相似文献
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Okabe S. Yuasa S. Kaneko S. 《Dielectrics and Electrical Insulation, IEEE Transactions on》2007,14(2):312-320
To lower the insulation specifications (specifically, the lightning impulse withstand voltage) of a gas insulated switchgear (GIS) and thus cut the equipment cost while maintaining the high reliability of its insulation performance, it is necessary to define in an organized way the insulation characteristics for non-standard lightning impulse voltage waveforms that represent actual surge waveforms in the field and compare them with the characteristics for the standard lightning impulse waveform quantitatively. In this paper, first, lightning surge waveforms and disconnector switching surge waveforms at UHV, 500 kV, and 275 kV substations were analyzed and five non-standard lightning surge waveforms with basic frequencies of 0.6 to 5.0 MHz were identified. Next, high-voltage circuits that generate these non-standard lightning surge waveforms were designed and constituted using EMTP (electro magnetic transients program) based on a circuit with a gap, inductors, and resistors connected in series and resistors and capacitors connected in parallel. Further, circuits were actually constructed, to obtain voltage waveforms approximately equal to those designed. Finally, the dielectric breakdown voltage-time characteristics were measured under several different conditions for the quasi-uniform SF6 gas gap that represents an insulation element of a GIS. As a result, it was found that, in the tested range, the dielectric breakdown values for non-standard lightning impulse waveforms were higher than for the standard lightning impulse waveform by 6% to 32% 相似文献