公开(公告)号：US6141196A

公开(公告)日：2000-10-31

申请号：US32948

申请日：1998-03-02

申请人： William James Premerlani ,  David Jeremiah Hoeweler ,  Albert Andreas Maria Esser ,  James Patrick Lyons ,  Gerald Burt Kliman ,  Rudolph Alfred Albert Koegl ,  Mark Gerald Adamiak

发明人： William James Premerlani ,  David Jeremiah Hoeweler ,  Albert Andreas Maria Esser ,  James Patrick Lyons ,  Gerald Burt Kliman ,  Rudolph Alfred Albert Koegl ,  Mark Gerald Adamiak

IPC分类号： G01R19/25 ,  H02H1/00 ,  H02H3/00

CPC分类号： H02H1/0092 ,  G01R19/2513 ,  G01R31/343

摘要： A method for obtaining a power system phasor includes sampling a power system signal at instants determined by a nominal power system frequency to provide a plurality of data samples; using the data samples to estimate a phasor having an elliptical trajectory; generating a deviation formula representing a frequency deviation between actual and nominal power system frequencies; and using the deviation formula to perform a coordinate transform of the estimated phasor to provide a scaled phasor having a substantially circular trajectory. If the data samples are unevenly spaced, a method in another embodiment includes minimizing squares of errors between the unevenly spaced data samples and an approximating sinusoidal function of the data samples. Power system phasors can be used to detect turn faults by providing scaled current and voltage phasors; extracting fundamental voltage and current phasors; and applying a symmetrical component transform to the fundamental voltage and current phasors to obtain symmetrical component voltage and current phasors for use in determining the existence of a turn fault. Variance calculations and/or trigonometric function fits can be used to increase sensitivity of fault detection.

摘要翻译： 一种用于获得电力系统相量的方法包括在由标称电力系统频率确定的时刻对电力系统信号进行采样，以提供多个数据样本; 使用数据样本来估计具有椭圆轨迹的相量; 产生表示实际和标称功率系统频率之间频率偏差的偏差公式; 并且使用偏差公式来执行所估计的相量的坐标变换，以提供具有基本圆形轨迹的缩放相量。 如果数据采样不均匀，则另一实施例中的方法包括最小化不均匀间隔的数据样本之间的误差平方和数据采样的近似正弦函数。 电力系统相量可用于通过提供定标的电流和电压相量来检测转向故障; 提取基波电压和电流相量; 并将对称分量变换应用于基波电压和电流相量，以获得用于确定匝间故障的存在的对称分量电压和电流相量。 方差计算和/或三角函数拟合可用于提高故障检测的灵敏度。