基于宽频模型的配电变压器防雷措施影响因素研究

为有效分析配电变压器遭受雷击时的过电压情况,通过ATP-EMTP软件搭建了基于宽频模型的配电变压器防雷分析模型,并对影响配电变压器防雷性能的几项主要因素进行了仿真计算。根据仿真结果可得结论:配电变压器高压侧安装了典型YH5W-17/50型避雷器时,在遭受30 kA及以上雷电流侵入时,其高压进线端和中性点电压有可能超过规程要求的耐受限值;配电变压器接地电阻越大,中性点雷击过电压越高;避雷器至配电变压器高压端的引线在雷击下会产生明显的附加过电压。最后,针对以上结论给出了相应的建议。     

重庆某10kV线路防雷问题分析及改造措施研究

重庆10kV回沙线在雷电活动频繁地区,雷害故障情况较为严重。通过对整条线路易受雷击点和配电变压器防雷保护进行现场调研,从地形对雷电的影响、杆塔高度过高使雷击闪络次数增加和配电变压器防雷存在的问题等方面分析了雷害事故多发的原因,并在此基础上提出了架设耦合地线、加装保护间隙、完善配电变压器保护等防雷措施,达到提高线路耐雷水平,确保配电线路供电可靠。     

防城港市配电变压器的防雷保护

根据防城港供电局配电变压器雷击损坏的情况，分析了多雷地区配电变压器被雷击损坏的原因，提出了多雷地区配电变压器防雷保护的技术措施，经过两年多时间运行检验，证明此防雷保护技术措施是有效的。     

新型防雷配电变压器(续)——关于BHQ的选择

1 前言 新型防雷配电变压器系经国家专利局于1992年4月批准的专利产品。笔者曾在《广东电力》1993年第4期发表“新型防雷节能配电变压器”(以下称该文为“前文”)。前文阐述了Yzn结线的配电变压器能抑制雷击时正、反变换过电压的功能,新型防雷变压器的防雷线圈FL替代     

配电变压器雷害事故分析与防雷保护措施探讨

对山区、重雷区配电网雷击损坏的事故进行了认真的调查、分析，特别分析了山区农村电网的雷电活动、雷击变压器的损坏、配电网和配电变压器的防雷保护，如避雷器的选型、安装以及变压器的接地引下线和接地装置的状况．针对山区重雷区配电变压器在防雷保护上存在的问题和不足，提出了综合的防雷保护方案．     

山区配电变压器雷害事故分析及防雷措施研究

对山区配电变压器雷击损坏的事故进行了认真的调查、分析,总结出事故的原因。针对山区重雷区配电变压器在防雷保护上存在的问题和不足,提出了综合的防雷保护方案。     

新型防雷配电变压器中BHQ等的选择

新型防雷配电变压器中ＢＨＱ等的选择１．前言新型防雷配电变压器系经国家专利局于１９９２年４月批准的专利产品，笔者曾在《变压器》１９９３年第６期发表“新型防雷配电变压器”一文（本文论述中称为”前文”）前文阐述了Ｙ，ｚｎ结线的配电变压器能抑制雷击时正、反变...     

不同接线组别的配电变压器雷击建模及雷电防护性能分析*

由雷击引发的变压器事故严重威胁电网的安全可靠运行。为研究Dyn11型和Yyn0型配电变压器的防雷性能,考虑绕组接线方式对分布电容参数、零序磁通分布的影响,并根据Dyn11型和Yyn0型配电变压器防雷接地特性的不同,运用ATP EMPT和ANSOFT Maxwell软件对两种类型的配电变压器进行雷击建模,对防雷性能开展了定量计算和对比分析。结果表明：三角形绕组冲击电流产生的总磁势和二次侧相反,由于雷电流在每个铁心柱上产生的总磁势都很小,因此逆变换过电压可看作为零,选用三相五柱式配电变压器对逆变换过电压的抑制作用明显。不同接线组别的配电变压器绕组分布参数不同,Dyn11型配电变压器具有较好的防雷性能,而且加装避雷器后,雷电过电压幅值大幅降低,防雷效果好。     

本电变压器防雷保护的研究

由于正、逆变换过电压的作用，配电变压器的雷击损坏率一直很高，低压用电设备因雷击损坏的情况也很严重。对此，进行了更进一步的研究，并提出了一种新的配电变压器防雷保护方法。通过在现场5年的大量运行，证明其防雷效果非常理想。     

广东某山区配电变压器防雷措施分析与探讨

针对广东某山区配电变压器雷击事故,介绍了该地区配电变压器的防雷保护现状,从老式避雷器的影响,正反变换过电压的影响,配电变压器接地方式影响,避雷器接地引下线影响四个方面分析了雷害事故发生的原因,提出了防雷害事故的整改措施:①更换老式阀型SiC避雷器。②在配电变压器高低压侧同时安装ZnO避雷器。③使用正确的变压器防雷接地、工作接地方式。④分别从技术上和管理上消除避雷器接地线被盗现象。通过以上整改,消除了该地区配电变压器防雷保护的薄弱环节,提高了供电可靠性。     

重庆某10kV线路综合防雷措施研究

重庆10kV井塘线线路走廊地形复杂,沿线有化工园区且有几处跨越山沟和河流造成线路档距较大,雷害故障情况较为严重。通过对整条线路易受雷击点的和配电变压器防雷保护的现场调研,从地形对雷电的影响、污秽使绝缘子绝缘水平降低和配电变压器防雷存的问题等方面分析了雷害事故多发的原因,并在此基础上提出了架设耦合地线、加装保护间隙、完善配电变压器保护等防雷措施,达到提高线路耐雷水平,确保配电线路的供电可靠性。     

Voltage distribution in multi-cascaded transformer

The voltage distribution for lightning surges in multicascaded transformers that will be used for converter transformers in self-excited dc transmission was studied using model transformers. There was good agreement between measured data and calculated results. It was shown that our calculation program has sufficient accuracy for estimating voltage distribution. Maximum voltages in high-voltage windings for lightning surges were below 120% and transfer voltages to the converting circuit were below about 5%. Therefore, there were no serious problems in cascaded transformers for lightning surges. However, their voltage distribution was not satisfactory when the same transformers were connected in cascade. We determined by a simulation that the distribution could be improved by modifying transformer structures according to their position in the cascade connection. © 1998 Scripta Technica. Electr Eng Jpn, 122(1): 17–24, 1998     

不同接线配电变压器防雷性能浅析

为提高配网运行可靠性,通过对Yyn0、Dyn11和Yzn11三种接线组别配变的防雷性能进行分析与比较,提出各种配变接线组别的选用原则。     

雷电侵入波作用下的变压器绕组建模

本文以110kV变电站的变压器为例,采用MATLAB计算变压器参数,用EMTP进行不同情况下的雷电侵入波仿真计算,分析在雷电侵入波作用下变压器电位梯度分布规律,以供变电站在选择防雷保护方案时进行参考。     

Evaluation of Breakdown Characteristics of Oil-immersed Transformers under Non-standard Lightning Impulse Waveforms - Method for Converting Non-standard Lightning Impulse Waveforms into Standard Lightning Impulse Waveforms

To lower the insulation specifications (specifically, the lightning impulse withstand voltage) of oil-immersed transformers and thus reduce equipment cost while maintaining high insulation reliability, it is required to identify the insulation characteristics under non-standard lightning impulse waveforms that are associated with actual surge waveforms in the field and quantitatively compare them with the characteristics under the standard lightning impulse waveform. In the previous research, field overvoltages in the lightning surge time region were analyzed, and four typical non-standard lightning impulse waveforms were defined. These four waveforms were used to measure the breakdown voltages and the partial discharge inception voltages on three models of the winding insulation elements of oil-immersed transformers. The average breakdown voltages were evaluated in terms of the overvoltage duration. This paper describes a method for converting of non-standard lightning impulse waveforms into standard lightning impulse waveforms with equivalent stress for the insulation. The constructed algorithm was applied to four examples representing two types of non-standard lightning waveforms. Due to the conversion into standard lightning impulse waveforms, the crest values were reduced by 14% to 26%. This seems to be a potential for reduction of lightning impulse insulation specifications of oil-immersed transformers.     

A computational tool to assist the analysis of the transformer behavior related to lightning

This paper proposes the application of computational intelligence techniques to assist complex problems concerning lightning in transformers. In order to estimate the currents related to lightning in a transformer, a neural tool is presented. ATP has generated the training vectors. The input variables used in Artificial Neural Networks (ANN) were the wave front time, the wave tail time, the voltage variation rate and the output variable is the maximum current in the secondary of the transformer. These parameters can define the behavior and severity of lightning. Based on these concepts and from the results obtained, it can be verified that the overvoltages at the secondary of transformer are also affected by the discharge waveform in a similar way to the primary side. By using the tool developed, the high voltage process in the distribution transformers can be mapped and estimated with more precision aiding the transformer project process, minimizing empirics and evaluation errors, and contributing to minimize the failure rate of transformers.     

户外用高压电动机及其输配电线路的防雷措施

分析了户外用高压三相异步电动机及其输配电线路中的高压输电线及其变压器的防雷措施,特别是在高原地区和林区及水稻田潮湿地区的特别雷电防护措施,对户外安装的高压电机及高压输电线的防雷击具有一定的保护作用.     

Evaluation and application of oil-immersed zinc oxide elements enclosed in pole-mounted distribution transformers

Voltage due to lightning surge is now a major problem to be overcome to ensure full reliability of any power supply. Hence, gapless oil-immersed surge arresters using zinc oxide elements have been applied to pole transformers. These surge arresters are used as a means of insulation coordination for pole transformers. These arresters contribute to the reduction of the number of failure of pole transformers. This paper describes applications and effects of specially developed oil-immersed surge arresters in pole transformers on 6.6-kV distribution lines. © 1997 Scripta Technica, Inc. Electr Eng Jpn, 121(2): 37–46, 1997     

大型整流变压器雷电冲击耐受试验

介绍了大型整流变压器雷电冲击耐压试验方法,并利用HIAS742高分辨率脉冲分析系统对变压器试品的试验结果进行了判断和分析,为今后大型整流变压器的雷电冲击耐压试验提出了一些建设性意见。