公开(公告)号：US5446387A

公开(公告)日：1995-08-29

申请号：US124034

申请日：1993-09-21

申请人： Leif Eriksson ,  Murari M. Saha

发明人： Leif Eriksson ,  Murari M. Saha

IPC分类号： G01R31/08

CPC分类号： G01R31/085 ,  H02H3/40

摘要： A method and a device for determining the distance from a measuring station to a fault on a transmission line based on a fault model of a transmission network while taking into consideration the zero-sequence impedance and, where assuming a fault current, while taking into consideration the feeding of fault current to the fault point from both ends of the transmission line (FIG. 3 ).

摘要翻译： 一种在考虑到零序阻抗的情况下，基于传输网络的故障模型来确定从测量站到传输线上的故障的距离的方法和装置，并且在考虑到故障电流的同时考虑 从传输线的两端向故障点馈送故障电流（图3）。

公开(公告)号：US5493228A

公开(公告)日：1996-02-20

申请号：US311124

申请日：1994-09-23

申请人： Leif Eriksson ,  Murari M. Saha

发明人： Leif Eriksson ,  Murari M. Saha

IPC分类号： H02H7/26 ,  G01R31/14

CPC分类号： H02H7/26

摘要： A method and a device, after a fault has occurred in a power network, for measuring and recreating the phase currents I.sub.B prior to the occurrence of the fault by determining continuously, starting from sampled measured values of the phase currents up to the time of the fault for each phase, the amplitude I and the phase angle .phi. of the phase currents based on two consecutive sampled measured values, whereupon a comparison is made between the last determined value I.sub.k obtained and the rated current I.sub.n of the power network. If I.sub.k is greater than I.sub.n, it is considered that a fault has occurred and the phase currents prior to the fault are indicated as I.sub.B =I.sub.k-1 .multidot.sin (.phi..sub.k-1 +.omega.(t-t.sub.k-1)).

摘要翻译： 在电力网络发生故障之后的方法和装置，用于通过连续地确定故障发生之前的相电流IB的测量和重新创建，从相电流的采样测量值开始直至时间 基于两个连续采样的测量值，相位电流的振幅I和相位角度phi，从而在所获得的最后确定值Ik和电力网络的额定电流In之间进行比较。 如果Ik大于In，则认为发生故障，故障前的相电流表示为IB = Ik-1sin（phi k-1 +ω（t-tk-1））。

公开(公告)号：US5399974A

公开(公告)日：1995-03-21

申请号：US75895

申请日：1993-06-14

申请人： Leif Eriksson ,  Murari M. Saha

发明人： Leif Eriksson ,  Murari M. Saha

IPC分类号： H02H3/38 ,  H02H7/26 ,  G01R31/08

CPC分类号： H02H7/26 ,  H02H3/385

摘要： A method and a device for determining the fault current which occurs in case of a fault through a short circuit between phases or from phase/phases to ground. A measure of the fault current can be obtained by a linear combination of the sum of measured current samples for each phase at two adjacent points in time and in which each of these sample values is multiplied by a coefficient which is chosen such that the fault current gets into phase with the positive- and negative-sequence current changes.

摘要翻译： 一种用于确定在相间或从相/相到地之间通过短路发生故障的故障电流的方法和装置。 故障电流的测量可以通过两个相邻时间点的每个相位的测量电流采样之和的线性组合来获得，其中这些采样值中的每一个乘以被选择为使得故障电流 与正序和负序电流变化相变。

公开(公告)号：US5390067A

公开(公告)日：1995-02-14

申请号：US21074

申请日：1993-02-23

申请人： Leif Eriksson ,  Murari M. Saha ,  Kjell Svensson

发明人： Leif Eriksson ,  Murari M. Saha ,  Kjell Svensson

IPC分类号： H02H3/38 ,  H02H3/26 ,  H02H3/40

CPC分类号： H02H3/385

摘要： A method and a device for phase selection for single-pole tripping of high-impedance ground faults in direct grounded power networks. Starting from the ratio of the negative-sequence voltage to the zero-sequence current (U2/I0) and the ratio of the negative-sequence voltage to the positive-sequence voltage (U2/U1), two criteria with different conditions are formed, each of which indicating a faulted phase, and if both criteria indicate the same phase as faulted, single-pole tripping can take place.

摘要翻译： 一种用于直接接地电网中高阻抗接地故障单极跳闸相位选择的方法和装置。 从负序电压与零序电流（U2 / I0）的比值以及负序电压与正序电压（U2 / U1）的比率开始，形成了具有不同条件的两个标准， 每个指示故障相位，并且如果两个标准指示与故障相同的相位，则可以发生单极跳闸。

公开(公告)号：US5375026A

公开(公告)日：1994-12-20

申请号：US998725

申请日：1992-12-30

申请人： Leif Eriksson ,  Murari M. Saha

发明人： Leif Eriksson ,  Murari M. Saha

IPC分类号： H02H1/04 ,  H02H3/26 ,  H02H3/32

CPC分类号： H02H3/26 ,  H02H1/04

摘要： A method and a device for preventing overstabilization of longitudinal differential protections in case of internal faults on power lines, which may take place when a fault situation, which is indicated as an external faults, is in reality an internal fault. The invention comprises criteria which finally provide information as to whether the longitudinal differential protection is to enter into operation. The criteria comprise level and directional determination of the currents which are measured in the terminals of the power lines, checking whether these have the same direction, and so on.

摘要翻译： 一种用于防止在电力线路内部故障的情况下纵向差动保护的过度稳定的方法和装置，当作为外部故障指示的故障情况实际上是内部故障时，这可能发生。 本发明包括最终提供关于纵向差动保护是否投入运行的信息的标准。 标准包括在电力线的端子中测量的电流的电平和方向确定，检查这些电流是否具有相同的方向等等。

公开(公告)号：US5352983A

公开(公告)日：1994-10-04

申请号：US983728

申请日：1992-12-01

申请人： Leif Eriksson ,  Murari M. Saha

发明人： Leif Eriksson ,  Murari M. Saha

IPC分类号： G01R31/08 ,  H02H7/26

CPC分类号： G01R31/08 ,  H02H7/267

摘要： The invention relates to a method and a device for detecting a flashover between conductors in power transmission lines of different voltage levels suspended from the same towers and wherein the power lines are included in a power network where one of the power lines is stated to be a high-voltage power line (1) and where the other power lines are connected to the high-voltage line via transformers of a known transformer ratio (am) and internal impedance (ZXm) and wherein the line impedances (ZL) are known. Specific to the invention is that the fault current which is caused by a flashover is set to be equal to a detected current change in any of the phases in the high-voltage line. With this assumption an equation system can be set up with the aid of which the relative distance to fault n (0

摘要翻译： 本发明涉及一种用于检测从同一塔悬挂的不同电压电平的输电线路中的导体之间的闪络的方法和装置，其中电力线包括在电力网络中，其中一条电​​力线被称为 高压电力线（1），其他电力线通过已知变压器比（am）和内部阻抗（ZXm）的变压器连接到高压线，并且其中线路阻抗（ZL）是已知的。 本发明的特征在于，将由闪络引起的故障电流设定为与高压线路中的任一相的检测电流变化相等。 通过这个假设，可以建立方程系统，借此可以确定与故障n（0

公开(公告)号：US06336059B1

公开(公告)日：2002-01-01

申请号：US09192956

申请日：1998-11-17

申请人： Damir Novosel ,  Bernhard Bachmann ,  Yi Hu ,  David G. Hart ,  Murari M. Saha

发明人： Damir Novosel ,  Bernhard Bachmann ,  Yi Hu ,  David G. Hart ,  Murari M. Saha

IPC分类号： G05B1900

CPC分类号： H02H3/40

摘要： A reach-measurement method is used in connection with a series-compensated line of a power system. The series-compensated line includes an installed series capacitance having a bus side and a line side, and a non-linear protection device parallel to the installed series capacitance. The series-compensated line has a line current, a bus side voltage, and a line side voltage. The series capacitance and the non-linear protection device have a capacitance voltage thereacross equal to the bus side voltage minus the line side voltage. In the method, a number (n) of line current samples are measured, where such samples are representative of values of a line current waveform at successive instants of time on the series-compensated line. Capacitance voltage values are computed based on the measured line current samples in accordance with an equation which takes into account the non-linear protection device parallel to the installed series capacitance. A prescribed power system function is then performed based on the computed capacitance voltage values.

摘要翻译： 与电力系统的串联补偿线结合使用到达测量方法。 串联补偿线包括具有总线侧和线路侧的安装的串联电容以及与安装的串联电容并联的非线性保护装置。 串联补偿线路具有线路电流，总线侧电压和线路侧电压。 串联电容和非线性保护装置的电容电压与母线侧电压减去线路侧电压相等。 在该方法中，测量线数电流样本数（n），其中这些采样代表串联补偿线上连续时刻的线电流波形的值。 电容电压值是根据测得的线路电流样本根据考虑到与安装的串联电容平行的非线性保护装置的方程计算的。 然后基于计算的电容电压值执行规定的电力系统功能。

公开(公告)号：US5956220A

公开(公告)日：1999-09-21

申请号：US19321

申请日：1998-02-05

申请人： Damir Novosel ,  Yi Hu ,  Murari M. Saha

发明人： Damir Novosel ,  Yi Hu ,  Murari M. Saha

IPC分类号： H02H3/40 ,  H02H7/26 ,  H02H3/00

CPC分类号： H02H7/267 ,  H02H3/40

摘要： An adaptive distance relaying system provides improved performance for parallel circuit distance protection. The system utilizes the parallel circuit's current, when available, in conjunction with measurements of voltage and current on the protected line to compensate for the zero sequence current mutual coupling effect. The sequence current ratio (zero or negative sequence) is used to avoid incorrect compensation for relays on the healthy circuit. If the parallel circuit current is not available and the line operating status is, the best zero sequence current compensation factors are selected accordingly as a next level adaptation. If both the parallel circuit current and line operating status are unavailable, a fallback scheme that offers better results than classical distance protection schemes is employed.

摘要翻译： 自适应距离中继系统为并联电路距离保护提供了改进的性能。 该系统在可用时利用并联电路的电流与受保护线路上的电压和电流的测量结合，以补偿零序电流互耦效应。 顺序电流比（零或负序）用于避免健康电路上继电器的不正确补偿。 如果并联电路电流不可用并且线路运行状态是，则最佳的零序电流补偿因子被相应地选择为下一级适配。 如果并联电路电流和线路运行状态都不可用，则采用比传统距离保护方案更好的结果的回退方案。

公开(公告)号：US5367425A

公开(公告)日：1994-11-22

申请号：US59854

申请日：1993-05-11

申请人： Murari M. Saha ,  Per Wennerlund

发明人： Murari M. Saha ,  Per Wennerlund

IPC分类号： H02H3/28 ,  H02H3/32

CPC分类号： H02H3/283

摘要： A method and a device for preventing understabilization of longitudinal differential protections in case of external faults and current transformer saturation. The invention comprises an extension of the state of the art with regard to stabilization of longitudinal differential protections in such a way that the values (A1, A2, . . . An), (.phi.1, .phi.2, . . . .phi.n), obtained via current measurement (C1, C2, . . . Cn) and Fourier filters (4, 5, 6), for determining the function characteristic of the protection under certain conditions as regards current amplitude and current transformer saturation are given corrected values (A1k, A2k, . . . Ank), (.phi.1k, .phi.2k, . . . .phi.nk) (FIG. 2).

摘要翻译： 一种用于在外部故障和电流互感器饱和的情况下防止纵向差动保护的不稳定的方法和装置。 本发明包括关于纵向差动保护的稳定性的现有技术的延伸，使得值（A1，A2，...），（phi 1，phi 2，...，phi n） 通过电流测量（C1，C2 ... Cn）和傅立叶滤波器（4,5,6）获得的，用于确定在某些条件下关于电流幅度和电流互感器饱和度的保护的功能特性的校正值（ A1k，A2k，...，Ank），（phi 1k，phi 2k，...，phi nk）（图2）。

公开(公告)号：US4731688A

公开(公告)日：1988-03-15

申请号：US30448

申请日：1987-03-27

申请人： Gunnar Nimmersjo ,  Murari M. Saha

发明人： Gunnar Nimmersjo ,  Murari M. Saha

IPC分类号： H02H3/00 ,  H02H7/26 ,  H02H3/38

CPC分类号： H02H7/265

摘要： A method and device for range limitation and direct tripping for protection in the event of a fault on an electrical power line extending between two stations (P, Q) involves employing a travelling wave model in one of the stations (P) which, with the aid of measured currents and voltages in that station, to calculate the voltage distribution at a number of control points along the line. The range of the protection device is indicated as the distance between the measuring station and that control point for which a voltage difference (.delta.u) becomes equal to zero. The voltage difference consists of the difference between the absolute value of a voltage differene between the absolute value of a voltage difference (.DELTA.u), formed as the sum of a voltage value (U") calculated with the travelling wave model for the control point at a certain time, and the corresponding voltage value (U') one half-period earlier and the absolute value of the latter voltage value. When the voltage difference becomes greater than zero, direct tripping can be initiated.