共查询到17条相似文献,搜索用时 625 毫秒
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配电网接地故障定位传递函数法的试验 总被引:6,自引:0,他引:6
配电网接地故障定位的传递函数法采用了注入高频信号获得故障信息的手段。大量仿真计算结果显示,该方法对配电网接地故障定位具有一些其他方法所不具有的优点,故对该方法进行了实验室线路模拟试验来进一步探讨论证。文中介绍了传递函数法试验线路模型,并对试验结果采用数字信号处理等手段进行了分析,将分析结果与已经获得的结论进行对比,验证了该方法的有效性,从而用试验手段证明了传递函数法在配电网接地故障中是切实可行的,为传递函数法的实际应用进行了试验性的基础准备工作。 相似文献
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目前电磁时间反演(electromagnetic time reversal, EMTR)多应用在单一线路故障定位,且现有判据在高阻抗接地情况下效果不理想。针对上述问题,基于EMTR故障定位原理和均匀传输线理论推导了传播过程中线路故障信号与测量信号的传递函数,根据传递函数的相关性提出了P范数判据。利用ATP-EMTP搭建10 kV配电网线路,对比了2范数与P范数判据在复杂配电网中的定位性能,并验证了所提判据在混合配电网线路的适用性。最后,分析了配电网发生低阻抗及高阻抗接地故障下P范数判据的鲁棒性。仿真结果表明,该方法在过渡电阻高达3 kΩ的情况下能准确定位,且定位精度高,受噪声、故障类型和采样频率的影响小。 相似文献
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为解决配电网接地故障的定位难题,在分析配电网接地故障行波零模与线模分量传输特性的基础上,提出了一种配电网接地故障定位新方法。该方法采用合适的小波变换标定零线模行波波头,并根据配电网故障行波历史数据拟合零线模时间差与故障距离、零线模时间差与零模波速的对应关系曲线,然后据此关系曲线提出了基于零线模传输时差的故障区段判别方法,最后研究了基于双端行波零模分量的配电网故障精确定位新方法,可在线路接地故障情况下准确判别故障区段并精确计算故障点位置。该方法具有较高的定位准确度,可有效解决配电网接地故障定位难题,仿真分析验证了该方法的有效性和准确性,有望在配电网中得到实际应用。 相似文献
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针对串补给线路距离保护带来的超越误动问题,提出了一种基于异构边界的串补输电线路单端量全线速动保护原理。该原理将安装于线路一侧的串补装置作为线路保护范围的异构边界,利用单端测量信息构建R-L微分方程求解故障距离,并采用最小二乘算法对故障距离进行拟合估计,根据测距结果的拟合误差可以判断故障点与串补电容之间的相对位置关系,从而实现串补线路的全线速动保护。所提方法应用等传变理论克服了电容式电压互感器暂态传变误差以及线路分布电容对故障测距精度的干扰,仿真表明能够在40 ms内快速切除串补线路的内部故障。 相似文献
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Characterization and modeling of in-building power lines for high-speed data transmission 总被引:1,自引:0,他引:1
Tang L.T. So P.L. Gunawan E. Guan Y.L. Chen S. Lie T.T. 《Power Delivery, IEEE Transactions on》2003,18(1):69-77
This paper analyzes the characteristics of power lines in Singapore residential network in order to develop a channel model suitable to simulate its behavior for high-speed data transmission. The channel model, which describes the transfer function and noise characteristics of typical in-building power line channels in a frequency band from 1 to 10 MHz, is developed and tested through software simulation and hardware implementation. The transfer function is described by an echo model and the noise spectrum is derived statistically from measurements on actual power lines. Some measurement results on power line impedance, noise and attenuation are presented. The results are based on measurements between line and neutral conductors in a 230-V power line network. From the results obtained so far, the impedance, noise and attenuation of power lines exhibit variations with frequency, time and location. 相似文献
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Heng-xu Ha Bao-hui Zhang Zhi-lai Lv 《Power Delivery, IEEE Transactions on》2003,18(4):1147-1151
A new fault location principle using one terminal voltage and current data for EHV transmission lines is described in this paper, which is based on distributed parameter line model, breaking through the traditional single-ended fault location ideas. The voltage profile along the healthy line could be calculated using single-ended voltage and current data; however, the voltage profile behind the fault point is not true for a faulted line. Even though, notice the fact that the norm value of derivative function of the "fictitious profile" to distance is minimum at fault point, based on which the fault location function is constructed. The numerical algorithm is also described; this principle is proved by EMTP simulations to be immune to fault resistance, fault types, and fault inception angle. Theoretically, the accuracy of the principle is proportional to the sampling rate of the locator. 相似文献
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Fault Location for Single-Circuit Line Based on Bus-Impedance Matrix Utilizing Voltage Measurements 总被引:1,自引:0,他引:1
Yuan Liao 《Power Delivery, IEEE Transactions on》2008,23(2):609-617
Diverse transmission line fault location algorithms have been proposed in the past depending on measurements available. Existing algorithms usually require measurements captured from buses of a faulted line. By taking advantage of the bus-impedance matrix technique, this paper presents a possible fault location approach for single-circuit lines utilizing only voltage measurements from one or two buses, which may be distant from the faulted line. With the addition of a fictitious bus where the fault occurs, the transfer impedances of this bus and other buses are revealed as a function of the fault location. Based on the relationship between the bus voltage change due to fault and the transfer impedance, the fault location can be derived. Shunt capacitance of the line is ignored first and then fully considered based on distributed parameter line model. Electromagnetic transients program simulation studies have shown quite encouraging results. 相似文献
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基于双曲正切函数相位特性的高压长线路故障测距新算法 总被引:3,自引:3,他引:0
提出一种基于双曲正切函数相位特性高压长线路故障测距新算法,其在将故障位置作为已知条件看待并引入参考点与之匹配的思想基础上,构建了一个和双曲正切函数具有相同相位特性的测距函数。根据所取参考点与故障点相匹配时测距函数相位等于零这一特征进行定位。该方法理论上不存在伪根,所需运算量远小于传统方法的运算量,能有效克服传统方法存在的测距精度和测距速度此消彼长的矛盾。EMTDC仿真结果表明,该方法不受过渡电阻、故障位置和故障发生角等因素的影响,在线路参数严重不均匀情况下依然保持较高的测距精度,具有较好的鲁棒性。 相似文献