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11.发明授权公开(公告)号：US06573726B1
公开(公告)日：2003-06-03
申请号：US09563178
申请日：2000-05-02
IPC分类号： G01R3114
摘要： A system for detecting ground faults in a compensated electric power distribution network includes the determination of zero sequence voltage (V0) and zero sequence current (I0) on a power line and calculating the zero sequence conductance (G0) therefrom. The operation of the conductance calculation circuit occurs only under selected power line conditions involving minimum values of zero sequence voltage, zero sequence current and positive sequence voltage, to ensure the accuracy of a fault direction determination. The conductance values are processed on an adaptive basis in which the difference between the most recent conductance value and a conductance value from a selected previous point in time is determined and then compared against threshold values to make forward and reverse fault declarations.
摘要翻译： 用于检测补偿配电网中的接地故障的系统包括确定电源线上的零序电压（V0）和零序电流（I0），并从其计算零序电导（G0）。 电导计算电路的工作仅在包括零序电压，零序电流和正序电压的最小值的选定电力线条件下发生，以确保故障方向确定的精度。 电导值在自适应基础上进行处理，其中确定最近电导值与选定的先前时间点之间的电导值之间的差值，然后与阈值进行比较以产生正向和反向故障声明。
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公开(公告)号：US5731943A
公开(公告)日：1998-03-24
申请号：US582770
申请日：1996-01-04
摘要： An out-of-step blocking circuit is established with two additional zones in the impedance plane, with the circuit determining the time that the positive sequence impedance takes to move between the two zones. The distance elements for selected zones of protection for the relay are blocked if the impedance moves between the two zones at a rate less than a first threshold. However, a trip signal results if the rate of change is greater than the first threshold but less than a second threshold, indicating an unstable swing. Further, an inner blinder zone is established in the impedance plane within the additional two zones of protection. If the positive sequence impedance entering that zone does not move from that zone within a certain time during an otherwise out-of-step condition, the blocking signals are terminated.
摘要翻译： 在阻抗平面中建立了两个附加区域的失步阻塞电路，电路确定正序阻抗在两个区域之间移动的时间。 如果阻抗以小于第一阈值的速率在两个区域之间移动，则继电器的所选保护区域的距离元件将被阻止。 然而，如果变化率大于第一阈值但小于第二阈值，则表示不稳定的摆动，则产生跳闸信号。 此外，在额外的两个保护区内的阻抗平面内建立内部阻挡区。 如果进入该区域的正序阻抗在另外的不合格条件下在一定时间内不会从该区域移动，则阻塞信号被终止。
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13.发明授权
公开(公告)号：US5349490A
公开(公告)日：1994-09-20
申请号：US961260
申请日：1992-10-15
摘要： A directional element measures the negative sequence voltage and the negative sequence current and from those quantities produces a scalar quantity related to the negative sequence impedance of a power transmission line relative to the location of the directional element. The scalar quantity is then compared against two threshold quantity settings, one to determine a forward fault, the other to determine a reverse fault. The scalar quantity must be less than the forward threshold quantity for a forward fault and greater than the reverse threshold quantity for a reverse fault.
摘要翻译： 方向元件测量负序电压和负序电流，并且从那些量产生与电力传输线相对于方向元件的位置的负序阻抗相关的标量。 然后将标量与两个阈值设置进行比较，一个用于确定正向故障，另一个用于确定反向故障。 标量必须小于正向故障的正向阈值，大于反向故障的反向阈值。
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公开(公告)号：US4686601A
公开(公告)日：1987-08-11
申请号：US782833
申请日：1985-10-02
CPC分类号： H02H3/402
摘要： A phase comparison type ground distance relay for a predetermined phase of three-phase AC transmission line includes a phase coincidence detector responsive to phase coincidence between an operating signal and a plurality of polarizing signals. Zero suppression networks are utilized for deriving second and third polarizing signals in order to improve discrimination between internal and external faults; thereby increasing the reliability of the relay operation and the security of the protection system. The second polarizing signal comprises that portion of a signal which exceeds a predetermined threshold value and which is related to the product of a signal proportional to the net current flowing in all three phases of the power system and the positive sequence replica impedence of the transmission line. The third polarizing signal comprises the sum of a signal related to the product of a negative sequence component of the current flowing in a predetermined phase of the AC power system and the positive sequence replica impedence of the transmission line; and that portion of a signal which exceeds a predetermined threshold value and which is related to the product of the net current flowing in all threephases of the system and the positive sequence replica impedence of the transmission line.
摘要翻译： 用于三相AC传输线的预定相位的相位比较型接地距离继电器包括响应于操作信号和多个极化信号之间的相位一致的相位一致检测器。 零抑制网络用于导出第二和第三极化信号，以改善内部和外部故障之间的区别; 从而提高了继电器操作的可靠性和保护系统的安全性。 第二极化信号包括超过预定阈值并且与在电力系统的所有三相中流动的净电流成比例的信号的乘积和传输线的正序复制阻抗的信号的部分相关 。 第三偏振信号包括与在AC电力系统的预定相中流动的电流的负序分量与传输线的正序复制阻抗的乘积相关的信号的和; 以及超过预定阈值并且与在系统的所有三相流动的净电流和传输线的正序复制阻抗的乘积相关的信号的那部分。
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15.发明授权Distance protection for parallel lines in networks with grounded neutral point and compensation of the neutral current 失效具有接地中性点的网络中并联线路的距离保护和中性点电流的补偿
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公开(公告)号：US1994427A
公开(公告)日：1935-03-12
申请号：US61728432
申请日：1932-06-15
发明人： ANDRE MATTHEY-DORET
IPC分类号： H02H3/40
CPC分类号： H02H3/402
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公开(公告)号：US1987285A
公开(公告)日：1935-01-08
申请号：US51754831
申请日：1931-02-21
发明人： GEORGES DARRIEUS
IPC分类号： H02H3/40
CPC分类号： H02H3/402
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公开(公告)号：US1897022A
公开(公告)日：1933-02-07
申请号：US52115331
申请日：1931-03-09
发明人： LEWIS WILLIAM A
IPC分类号： H02H3/40
CPC分类号： H02H3/402
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公开(公告)号：US20130043879A1
公开(公告)日：2013-02-21
申请号：US13371112
申请日：2012-02-10
申请人： Ari WAHLROOS , Janne ALTONEN
发明人： Ari WAHLROOS , Janne ALTONEN
IPC分类号： G01R31/14
CPC分类号： H02H3/402 , H02H1/0092
摘要： A method and an apparatus for detecting an earth fault on a three-phase electric line are provided. The apparatus includes means for determining a neutral admittance on the basis of a residual current and a residual voltage, means for comparing the determined neutral admittance to a predetermined operation characteristic to detect an earth fault on the three-phase electric line, and means for determining one or more harmonic components of the residual current and one or more harmonic components of the residual voltage. The harmonic components have frequencies n*fn such that n≧2 and fn is a fundamental frequency. The means for determining a neutral admittance are configured to use at least one of the determined one or more harmonic components of the residual current and at least one of the determined one or more harmonic components of the residual voltage for determining the neutral admittance.
摘要翻译： 提供了一种用于检测三相电线上的接地故障的方法和装置。 该装置包括用于基于剩余电流和剩余电压确定中性导纳的装置，用于将所确定的中性导纳与预定操作特性进行比较以检测三相电线路上的接地故障的装置，以及用于确定 剩余电流的一个或多个谐波分量和剩余电压的一个或多个谐波分量。 谐波分量具有频率n * fn，使得n≥2，fn是基频。 用于确定中性导纳的装置被配置为使用所确定的剩余电流的一个或多个谐波分量中的至少一个和所确定的残余电压的一个或多个谐波分量中的至少一个来确定中性导纳。
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