公开(公告)号：EP2223404B1

公开(公告)日：2015-05-27

申请号：EP08857782.0

申请日：2008-11-21

申请人： Cooper Technologies Company

发明人： KOJOVIC, Ljubomir, A. ,  BISHOP, Martin, P. ,  DAY, Timothy, R.

IPC分类号： H02H7/045 ,  H02H3/44

CPC分类号： H02H7/0455 ,  H02H1/043 ,  H02H3/44

公开(公告)号：EP2223404A1

公开(公告)日：2010-09-01

申请号：EP08857782.0

申请日：2008-11-21

申请人： Cooper Technologies Company

发明人： KOJOVIC, Ljubomir, A. ,  BISHOP, Martin, P. ,  DAY, Timothy, R.

IPC分类号： H02H7/04

CPC分类号： H02H7/0455 ,  H02H1/043 ,  H02H3/44

摘要： A differential protection system for power transformers using Rogowski coils as current sensors can support an inrush current detection method based on sensing lows in the derivative of the sensed current. Effective detection of power transformer inrush conditions can enable blocking of a protection relay during inrush where the differential current may exceed a differential threshold value indicative of a fault without the presence of an actual fault. The outputs of the Rogowski coils, being proportional to the first time derivative of the sensed current, may be useful in the inrush detection method. Also, with reduced saturation concerns, the Rogowski coil protection system may employ a single slope response with increased sensitivity. A discrete time sampling technique for identifying low di/dt portions within the sensed current also may be useful in detecting power transformer inrush conditions.

摘要翻译： 使用罗柯夫斯基线圈作为电流传感器的电力变压器的差动保护系统可以支持基于感应电流导数中的低电平检测的浪涌电流检测方法。 电涌互感器浪涌条件的有效检测可以在浪涌期间阻断保护继电器，其中差动电流可能超过指示故障的差动阈值而不存在实际故障。 Rogowski线圈的输出与感应电流的一阶导数成正比，在涌入检测方法中可能很有用。 此外，随着饱和度降低，罗高夫斯基线圈保护系统可能会采用单一斜率响应，并提高灵敏度。 用于识别感测电流内的低di / dt部分的离散时间采样技术在检测电力变压器涌入情况中也可能是有用的。