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INTRODUCTIONTransmissionlinesofapowersystemaresubjecttomanykindsoffaults.Theprincipaltypesare :phase to earth ;doublephase to earth(phase phase earth) ;phase to phase ;three phase.Followingtheoccurrenceofatransmis sionlinefault,themaintenancecrewmustfinda… 相似文献
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An accurate algorithm for fault location of double phase-to-earth fault on transmission line of direct ground neutral system
is presented. The algorithm, which employs the faulted phase network and zero-sequence network as fault-location model in
which the source impedance at the remote end is not involved, effectively eliminates the effect of load flow and fault resistance
on the accuracy of fault location. The algorithm achieves accurate location by measuring only one local end data and is used
in a procedure that provides automatic determination of faulted types and phases, and does not require the engineer to specify
them. Simulation results showed the effectiveness of the algorithm under the condition of double phase-to-earth fault.
Project (No. 023801211) supported by the Key Science Foundation of Tianjin, China 相似文献
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The modern travelling wave based fault location principles for transmission lines are ana-lyzed. In order to apply the travelling wave principles to HVDC transmission lines, the special tech-nical problems are studied. Based on this, a fault locating system for HVDC transmission lines is developed. The system can support modern double ended and single ended travelling wave princi-ples simultaneously, and it is composed of three different parts: travelling wave data acquisition and processing system, communication network and PC based master station. In the system, the fault generated transients are induced from the ground leads of the over-voltage suppression ca-pacitors of an HVDC line through specially developed travelling wave couplers.The system was applied to 500 Kv Gezhouba-Nanqiao(Shanghai)HVDC transmission line in China. Some field op- eration experiences are summarized, showing that the system has very high reliability and accu- racy,and the maximum location error is about 3 km(not more than 0.3% of the total line length). Obviously, the application of the system is successful, and the fault location problem has finally been solved completely since the line operation. 相似文献
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Transmissionlinesformthebackboneofpowerutilityoperationsandachievethecontinuityofservicefromgenerat ingplantstotheusers.Linesaresubjecttomultifariouskindsoffaultsbecausetheyareexposedtotheelements .Thecausesoffaultaremultifarious .Linefaultmaybetriggeredbylight ningstrokes.Treesmayfallacrosslines .Fogandsaltsprayondirtyinsulatorsmaycausetheinsulatorstringstoflashover.Iceandsnowloadingmaycauseinsulatorstringstofailmechanically .Followingtheoccurrenceofalinefault,itisnecessaryforthemaintenance… 相似文献
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提出一种新的同杆架设输电线路故障定位算法 .该算法仅使用本地端的电压电流采样数据 .算法模型利用了非故障线的信息 ,有效排除了故障电阻和负荷对故障定位精度的影响 .计算机数字仿真验证结果表明 ,该算法精度较高 相似文献
7.
王志刚 《楚雄师范学院学报》2002,17(3):6-10
坚固性是软件可靠性的主要方面之一，并正在成为衡量软件质量的重要指标。基于软件的容错技术是实现软件系统坚固性的主要途径，包含了操作容错、数据容错、软件容错和硬件容错四个方面内容，其本质都是冗余方法，基本手段的故障检测与故障定位、故障包容与故障屏蔽、系统重构与故障恢复等，软件容错的基本方法是多样性设计，其代表性方法是恢复块RB和多版本编程NVP技术。本文同时简要介绍了容错技术的基本思想、方法及相关研究的发展概况。 相似文献
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复杂的配电网系统中,蝠鲼觅食优化算法存在后期搜索能力不足导致故障定位准确率下降的缺点。针对该问题,提出了一种基于阈值反馈蝠鲼觅食优化算法的多电源配电网故障定位方法。在确立适用于复杂多电源网络的故障定位数学模型的基础上,采用Limit阈值控制算法求得极值时的迭代次数;在算法位置更新阶段引入交流反馈机制,加快算法收敛速率;利用Sigmoid函数对算法进行二进制离散化,输出故障向量完成故障定位。在Matlab中建立故障定位仿真模型,对多种算法开展对比实验。结果表明,不同故障情况下,改进的配电网故障定位算法的定位速度与准确度均优于其他算法。 相似文献
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XU Gao-xiong 《重庆大学学报(英文版)》2011,10(2):78-83
It is important for the safety of transmission system to accurately calculate single-phase earth fault current distribution. Features of double sided elimination method were illustrated. Quantitative calculation of single-phase earth fault current distribution and case verification were accomplished by using the loop method. Influences of some factors, such as single-phase earth fault location and ground resistance of poles, on short-circuit current distribution were discussed. Results show that: 1) results of the loop method conform to those of double sided elimination method; 2) the fault location hardly influences macro-distribution of short-circuit current. However, current near fault location is evidently influenced; and 3) the short-circuit current distribution is not so sensitive to the ground resistance of poles. 相似文献
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图像识别在故障诊断中有重要作用.车轮踏面缺陷主要有剥离、裂纹2种形式.介绍了车轮踏面故障测试系统的原理及程序总体框图,它采用图像处理方法作为获取故障特征的手段,将聚类识别和判别分析的概念有机结合,实现了对故障的准确定位,为故障的及时维修提供了强有力的支持. 相似文献
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为了让用户对旋转门性能状况了如指掌,操作起来胸有成竹,同时为旋转门维修和管理提供参考资料,设计具有故障自诊断功能的旋转门是非常有必要的。以离线方式运行,通过适当的算法处理,给出系统故障信息,包括故障位置信息、故障程度信息和故障报警信息等,以便管理人员对症下药,及时采取措施,从而避免事故的发生。 相似文献
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A diagnostic signal current trace detecting based single phase-to-ground fault line identifica- tion and section location method for non-effectively grounded distribution systems is presented in thisi oaper. A special diagnostic signal current is injected into the fault distribution system, and then it is de- tected at the outlet terminals to identify the fault line and at the sectionalizing or branching point along the fault line to locate the fault section. The method has been put into application in actual distribution network and field experience shows that it can identify the fault line and locate the fault section correctly and effectively. 相似文献
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对数字电视CAS系统在使用过程中出现的不插卡或没有授权的情况下依然能看、接收时显示E15没有解密授权等典型故障,可由故障现象逆推,分析查找故障发生的位置和原因,从而快速解决问题,然后再顺着系统运行的顺序进行验证,是行之有效的方法．该方法既简单易行,又减少了维修成本,提高了维修效率． 相似文献
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用时域有限差分法研究了光在部分无序二维光子晶体波导中的传播特性．结果表明：介质柱的位置和大小无序对光予晶体波导的透射特性都有影响．仅当它的位置无序变化时,高频段缺陷带对无序度最敏感;仅当它的大小无序变化时,处于低频段缺陷带的高频端对无序度更敏感．当它的位置和大小都无序变化时,它的透射特性比仅受位置无序或大小无序影响更显著． 相似文献
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白献林 《南阳师范学院学报》2007,6(9):32-34
从边界扫描测试仪的功能要求入手,设计了一种基于虚拟仪器技术的测试仪。该仪器通过PC机的打印端口将测试向量施加到被测试系统并捕获测试响应,在PC机内部,对测试响应进行分析,判断电路工作是否正常,如果有故障,则给出电路的故障类型和具体位置。 相似文献
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张荣升刘丽桑邓慧琼李培强郑荣进 《福建工程学院学报》2021,(4):378-384
为提高配电网络中故障区段定位的准确性和高效性,基于馈线终端单元的配电网区段定位的研究,提出了一种在含分布式电源的配电网中用鲸鱼优化算法实现故障区段定位的方法。通过MATLAB对支路矩阵、电源接入情况进行编程,创建含多电源的IEEE33节点的配电网模型,完成配电网故障信息编码方式、开关函数和适应度函数的构造。对发生单点故障、多点故障,以及存在信息畸变的情况下发生故障的定位结果分析,结果表明,提出的鲸鱼算法能实现准确定位,其收敛性、准确性和高效性均优于传统粒子群算法、遗传算法以及最近的蝠鲼觅食算法。 相似文献
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利用LC谐振放大电路、HC-SR04超声波测距模块、PCF8591A/D模块、LCD12864液晶显示模块,以STC89C52单片机最小系统为框架,设计了一种简易照明暗线探测仪.它通过单片机采集两条暗线的电磁感应信号,利用超声波测距原理进行故障的准确定位. 相似文献
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基于小波分析的配电网故障选线方法研究 总被引：1，自引：0，他引：1
赵艳 《江西电力职业技术学院学报》2009,22(3)
提出了一种基于小波分析的配电网故障选线方法。通过剔除线路谐振状态的频带,利用小波包良好的分频特性,以适当带宽对故障后线路的暂态零序电流进行分解,从而实现在低频段下对各线路的零序电流进行小波重构,通过比较重构后的信号来实现选线。仿真实验表明,该选线方法受故障点位置、故障时刻、过渡电阻等因素影响较小,具有可靠性高、抗干扰能力强的特点,适用于中性点不接地的配电网。 相似文献
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描述了一种利用小波变换对T型线路进行快速保护的方案,保护单元使用各支路经同步化后的三相电压电流,使用小波变换提取故障电压电流频带中的暂态高频分量,进行故障检测与类型判别。建立了非对称T型线路仿真模型,针对不同故障位置、故障类型、故障初始角和故障过渡电阻进行仿真验证。结果表明,该方案快速,准确。 相似文献
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Maria Vintan 《浙江大学学报(A卷英文版)》2008,9(2):182-189
During ground faults on transmission lines, a number of towers near the fault are likely to acquire high potentials to ground. These tower voltages, if excessive, may present a hazard to humans and animals. This paper presents analytical methods in order to determine the transmission towers potentials during ground faults, for long and short lines. The author developed a global systematic approach to calculate these voltages, which are dependent of a number of factors. Some of the most important factors are： magnitudes of fault currents, fault location with respect to the line terminals, conductor arrangement on the tower and the location of the faulted phase, the ground resistance of the faulted tower, soil resistivity, number, material and size of ground wires. The effects of these factors on the faulted tower voltages have been also examined for different types of power lines. 相似文献