公开(公告)号：US06173216B2

公开(公告)日：2001-01-09

申请号：US09060508

申请日：1998-04-15

申请人： Khoi Vu ,  David G. Hart ,  Damir Novosel

发明人： Khoi Vu ,  David G. Hart ,  Damir Novosel

IPC分类号： H02J114

CPC分类号： H02H1/0092 ,  G01R19/2513

摘要： As a variation of the non-orthogonal filter, a phasor estimate is computed by using an N-point window. An aspect of the sub-window cosine filter is to repeat the basic cosine filter for only selected points of the window. In the end, a least-squares fit is used to obtain an estimate for the phasors components. Previous cosine techniques use a data window whose length is greater than 1 cycle while the present invention requires only 1 cycle.

摘要翻译： 作为非正交滤波器的变型，通过使用N点窗口来计算相量估计。 子窗口余弦滤波器的一个方面是仅对窗口的选定点重复基本余弦滤波器。 最后，使用最小二乘拟合来获得相量分量的估计。 以前的余弦技术使用长度大于1周期的数据窗口，而本发明仅需要1个周期。

公开(公告)号：US06397156B1

公开(公告)日：2002-05-28

申请号：US09192851

申请日：1998-11-17

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

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

IPC分类号： G01R2500

CPC分类号： H02H3/40 ,  H02H1/04

摘要： An accurate impedance measurement method for a power system transmission line is disclosed for improving various protection functions, i.e., distance protection and/or fault location estimation. The method is less sensitive to harmonics and other transient problems introduced to power systems by series capacitance and the like, and is easily incorporated into existing protective relays. In the method, a number (n) of current and voltage samples (Ik, Vk) representative of values of current and voltage waveforms are measured, respectively, at successive instants of time on a conductor in a power system. The number n is an integer greater than I and the index k takes on values of 1 to n. Resistance (R) and inductance (L) values are computed in accordance with an equation in which R and L are related to sums of differences in values of successive current and voltage samples. A prescribed power system function is then performed based on the computed R and L values.

摘要翻译： 公开了一种用于电力系统传输线路的精确阻抗测量方法，用于改进各种保护功能，即距离保护和/或故障位置估计。 该方法对通过串联电容等引入电力系统的谐波和其他瞬态问题较不敏感，并且容易地并入现有的保护继电器中。 在该方法中，分别在电力系统中的导体上的连续时刻分别测量表示电流和电压波形值的电流和电压样本数（Ik，Vk）的数量（n）。 数字n是大于I的整数，索引k取值为1到n。 电阻（R）和电感（L）值根据其中R和L与连续电流和电压样本的值的差的和相关的方程式来计算。 然后根据计算的R和L值执行规定的电力系统功能。

公开(公告)号：US06453248B1

公开(公告)日：2002-09-17

申请号：US09119792

申请日：1998-07-21

申请人： David G. Hart ,  Damir Novosel ,  Steven A. Kunsman

发明人： David G. Hart ,  Damir Novosel ,  Steven A. Kunsman

IPC分类号： G01R3100

CPC分类号： G01R31/088 ,  G01R31/085 ,  G01R31/086 ,  H02H1/0015 ,  Y04S10/522

摘要： An improved high impedance fault (HIF) detection system comprises an analyzer located at a circuit breaker or substation with feeders, wherein the analyzer analyzes current and/or voltage waveforms to detect a HIF on the feeder or on one of a plurality of laterals coupled to the feeder; a plurality of remote outage detectors located respectively at corresponding customer sites, each remote outage detector including a mechanism to detect a loss of potential or power at the corresponding site; and a computer in communication with the analyzer and the remote outage detectors.

摘要翻译： 改进的高阻抗故障（HIF）检测系统包括位于具有馈线的断路器或变电站的分析仪，其中分析器分析电流和/或电压波形，以检测馈线上的HIF或多个耦合到 进料器; 分别位于相应的客户位置的多个远程停机检测器，每个远程停电检测器包括用于检测对应站点的电位或电力损失的机构; 以及与分析仪和远程停机检测器通信的计算机。

公开(公告)号：US5832414A

公开(公告)日：1998-11-03

申请号：US939932

申请日：1997-09-29

申请人： David G. Hart ,  James D. Stoupis ,  Damir Novosel

发明人： David G. Hart ,  James D. Stoupis ,  Damir Novosel

IPC分类号： G01R19/25 ,  G01R23/00 ,  G01R23/16 ,  G01R23/10

CPC分类号： G01R19/2513 ,  G01R23/16 ,  G01R23/00

摘要： A new method of compensating for errors in phasor estimation due to oscillations caused by discrete fourier transforms used to estimate signal frequency is provided. The method uses a variable N-point DFT to compute one or more phasors based on data acquired from one or more sampled signals. At each sampling interval the change in phasor angle between the current sampling interval and the previous sampling interval is determined and used to estimate the instantaneous frequency of the signal. A non-oscillating phasor indicative of the instantaneous magnitude, angular frequency, and phase angle of the signal is generated based on the instantaneous frequency estimate. Instantaneous frequencies are averaged over a cycle of the signal to generate an average cycle frequency. In addition, a number of discrete frequencies and corresponding DFT windows based on a fixed sampling rate and a predetermined fundamental frequency of the signal are defined and used in estimating the instantaneous frequency. The DFT window is adjusted by setting it equal to the DFT window corresponding to the discrete frequency closest to the average cycle frequency. A generator protection system analyzing voltage and current signals output from a generator is also provided. The voltage and current signals are monitored by respective voltage and current sensors to produce a plurality of signals representative of voltage and current characteristics of the generator. The system comprises components for receiving and sampling signal input, and for processing the samples according to the inventive method.

摘要翻译： 提供了一种补偿由于用于估计信号频率的离散傅立叶变换引起的振荡引起的相量估计误差的新方法。 该方法使用可变N点DFT来基于从一个或多个采样信号获取的数据来计算一个或多个相量。 在每个采样间隔，确定当前采样间隔和先前采样间隔之间的相量角的变化，并用于估计信号的瞬时频率。 基于瞬时频率估计产生指示信号的瞬时幅度，角频率和相位角的非振荡相量。 瞬时频率在信号的周期上平均以产生平均周期频率。 另外，基于固定采样率和信号的预定基频定义了多个离散频率和相应的DFT窗口，并用于估计瞬时频率。 通过将DFT窗口设置为与最接近平均周期频率的离散频率对应的DFT窗口进行调整。 还提供了分析从发电机输出的电压和电流信号的发电机保护系统。 电压和电流信号由相应的电压和电流传感器监测，以产生代表发电机的电压和电流特性的多个信号。 该系统包括用于接收和采样信号输入的组件，并且用于根据本发明的方法处理样本。

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：US06584417B1

公开(公告)日：2003-06-24

申请号：US09425661

申请日：1999-10-22

申请人： Yi Hu ,  Damir Novosel ,  David G. Hart

发明人： Yi Hu ,  Damir Novosel ,  David G. Hart

IPC分类号： G01R3108

CPC分类号： G01R31/085 ,  H02H3/081 ,  H02H3/405

摘要： An electrical power system includes a transmission line for transmitting electrical power, series capacitance compensation series-coupled to the transmission line adjacent one end thereof, where the series compensation includes a capacitance having a value (−j XCAP), and a protective relay at the one end of the transmission line for monitoring line voltages and line currents on the transmission line. Upon sensing a fault, an impedance Z of the line is calculated based on the monitored line voltages and line currents. The calculated impedance Z is adjusted according to the value of the capacitance of the series compensation (−j XCAP) to result in a modified impedance ZMOD, and the phasor angle Of ZMOD is examined to determine the direction of the sensed fault. The fault is in a first direction if the phasor angle is between X and X+180 degrees and is in a second direction opposite the first direction if the phasor angle is between X+180 and X+360 degrees.

摘要翻译： 电力系统包括用于发送电力的传输线，串联耦合到其一端附近的传输线的串联电容补偿，其中串联补偿包括具有值（-j XCAP）的电容，以及保护继电器 传输线的一端用于监测传输线上的线路电压和线路电流。 在检测到故障时，根据被监测的线路电压和线路电流计算线路的阻抗Z。 根据串联补偿（-j XCAP）的电容值调整计算阻抗Z，得到修正的阻抗ZMOD，并检查ZMOD的相量角以确定感测故障的方向。 如果相量角在X和X + 180度之间，并且如果相量角在X + 180和X + 360度之间，并且处于与第一方向相反的第二方向，则故障处于第一方向。

公开(公告)号：US6154687A

公开(公告)日：2000-11-28

申请号：US60458

申请日：1998-04-15

申请人： David G. Hart ,  Damir Novosel ,  Robert A. Smith

发明人： David G. Hart ,  Damir Novosel ,  Robert A. Smith

IPC分类号： G01R19/25 ,  H02H3/38 ,  H02J1/14 ,  H02H7/00 ,  H02H9/00 ,  H02J3/02 ,  H02J17/00

CPC分类号： G01R19/2513 ,  H02H3/38

摘要： A high sample rate cosine filter eliminates DC components by summing them such that they sum to zero. A non-orthogonal cosine filter is also provided. When the cosine filter is applied for N=4 samples per cycle, the samples are separated by 90 degrees. However, at higher sampling rates, it is not necessary to wait for 90 degrees to estimate the phasor value. Non-orthogonal components are used to estimate the phasor value. The time delay associated with the cosine filter is reduced in the process.

摘要翻译： 高采样率余弦滤波器通过将它们相加来消除DC分量，使得它们总和为零。 还提供了非正交余弦滤波器。 当每个循环使用余弦滤波器N = 4个样本时，样本被分离90度。 然而，在更高的采样率下，不需要等待90度来估计相量值。 非正交分量用于估计相量值。 与余弦滤波器相关的时间延迟在该过程中减少。

公开(公告)号：US08869637B2

公开(公告)日：2014-10-28

申请号：US13038523

申请日：2011-03-02

申请人： Hossein Safari Zadeh ,  Damir Novosel

发明人： Hossein Safari Zadeh ,  Damir Novosel

IPC分类号： H02K5/22 ,  H02K5/04 ,  H02K15/14 ,  H02K15/00

CPC分类号： H02K5/22 ,  H02K5/04 ,  H02K15/00 ,  H02K15/14

摘要： An electric generator (1) includes a casing (2) that envelops a stator (3) and a rotor (4). The casing (2) has an aperture (5) through which the generator casing inside (7) is inspectable during generator operation. A method includes inspecting during generator operation, through the aperture (5) of the casing (2), the casing inside (7).

摘要翻译： 发电机（1）包括包围定子（3）和转子（4）的壳体（2）。 壳体（2）具有孔（5），在发电机运行期间可以检查发电机壳体（7）内的孔（5）。 一种方法包括在发电机操作期间，通过壳体（2）的孔（5），壳体（7）内的检查。

公开(公告)号：US20130066480A1

公开(公告)日：2013-03-14

申请号：US13607496

申请日：2012-09-07

申请人： Mevludin Glavic ,  Muhidin Lelic ,  Damir Novosel

发明人： Mevludin Glavic ,  Muhidin Lelic ,  Damir Novosel

IPC分类号： G05F5/00

CPC分类号： H02J3/14 ,  H02J3/24 ,  H02J13/0006 ,  H02J2003/007 ,  Y02B70/3225 ,  Y02E60/728 ,  Y02E60/74 ,  Y02E60/76 ,  Y04S10/265 ,  Y04S10/30 ,  Y04S20/222 ,  Y04S40/22

摘要： The disclosure relates to a method of detecting and managing voltage instability in power systems operations. The disclosed method identifies and follows Thevenin and load impedance values as they fluctuate in a power system using synchrophasor measurements. The values are recursively estimated and entered into calculations to identify stability margins through a simple P-Q plane representation to determine if load shedding is necessary.

摘要翻译： 本公开涉及一种检测和管理电力系统操作中的电压不稳定性的方法。 所公开的方法在使用同步相机测量​​的电力系统中波动时识别和跟随戴维南和负载阻抗值。 这些值被递归地估计并输入到计算中以通过简单的P-Q平面表示来确定稳定裕度，以确定是否需要负载脱落。

公开(公告)号：US06249230B1

公开(公告)日：2001-06-19

申请号：US09272017

申请日：1999-03-18

申请人： Thomas L. Baldwin ,  Damir Novosel ,  Ali F. Imece

发明人： Thomas L. Baldwin ,  Damir Novosel ,  Ali F. Imece

IPC分类号： G08B2100

CPC分类号： H02H3/17 ,  G01R31/025 ,  H02H3/042 ,  H02H3/165 ,  H02H3/33

摘要： A ground fault location system is used in a multi-phase ungrounded or high-impedance grounded power network. A signal generator is coupled to the network at a first location and generates for each network phase an individual non-DC voltage signal between such phase and ground. A ground fault detector is coupled to the network at a second location and has a summing device and an annunciator. The summing device is coupled to all of the phases of the network at such second location, sums any current passing therethrough, and produces a sum signal. The annunciator receives the sum signal and provides an indication when such signal is non-zero. Each phase of the network at the second location has a distribution current passing therethrough, the sum thereof normally being substantially zero and resulting in a substantially zero sum signal and the lack of an indication from the annunciator based on such distribution currents. When the second location is on a path between the first location and a ground fault, the individual voltage signal on at least one of the phases generates a fault current thereon through such path and results in a non-zero sum signal and an indication from the annunciator. When the second location is not on such path, none of the individual voltage signals generates a fault current on any phase through such path, resulting in a substantially zero sum signal and the lack of an indication from the annunciator.

摘要翻译： 接地故障定位系统用于多相不接地或高阻抗接地电网。 信号发生器在第一位置处耦合到网络，并且为每个网络相位产生这种相位和地之间的单个非直流电压信号。 接地故障检测器在第二位置处耦合到网络，并具有求和装置和信号器。 求和装置在这样的第二位置处耦合到网络的所有相位，对通过其中的任何电流求和，并产生和信号。 信号器接收和信号，并在这种信号不为零时提供指示。 在第二位置处的网络的每个阶段具有通过其的分配电流，其总和通常基本为零，并且导致基本上为零的和信号，并且基于这种分配电流缺少来自信号器的指示。 当第二位置在第一位置和接地故障之间的路径上时，至少一个相位上的单个电压信号通过这样的路径在其上产生故障电流，并且产生非零和信号和来自 报警器 当第二位置不在这样的路径上时，没有一个单独的电压信号通过这样的路径在任何相位上产生故障电流，导致基本上为零的和信号，并且没有来自信号器的指示。