公开(公告)号：US4980645A

公开(公告)日：1990-12-25

申请号：US489800

申请日：1990-03-05

申请人： Kenichiro Soma ,  Kazuo Kotani ,  Nobuju Takaoka ,  Chuki Ikeda ,  Moritada Marumo

发明人： Kenichiro Soma ,  Kazuo Kotani ,  Nobuju Takaoka ,  Chuki Ikeda ,  Moritada Marumo

IPC分类号： G01R27/18 ,  G01R31/02 ,  G01R31/12

CPC分类号： G01R27/18 ,  G01R31/021

摘要： A power cable such as a rubber or plastic insulated power cable is diagnosed to be detected an insulation deterioration resulted from water tree generated in an insulation material thereof. At first, charging current flowing from the power cable through a grounding conductor connected to a metal shielding layer thereof to the ground is measured under a state that a rated AC voltage is applied to the power cable. In accordance with the charging current, stray current flowing from the ground to the power cable is calculated. Then, a direct current component of the charging current is detected, and an intrinsic direct current component is calculated by subtracting the stray current from the direct current component. The insulation deterioration is diagnosed in accordance with the level of the intrinsic direct current component.

摘要翻译： 诊断出诸如橡胶或塑料绝缘电力电缆的电力电缆被检测到在其绝缘材料中产生的水树导致的绝缘劣化。 首先，在向电力电缆施加额定交流电压的状态下，测量从电力电缆流过与其金属屏蔽层连接的地线的接地的充电电流。 根据充电电流，计算从地面流向电力电缆的杂散电流。 然后，检测充电电流的直流分量，并通过从直流分量中减去杂散电流来计算本征直流分量。 绝缘劣化根据本征直流分量的水平进行诊断。

公开(公告)号：US5276401A

公开(公告)日：1994-01-04

申请号：US987061

申请日：1992-12-07

申请人： Kenichiro Soma ,  Kazuo Kotani ,  Nobuju Takaoka

发明人： Kenichiro Soma ,  Kazuo Kotani ,  Nobuju Takaoka

IPC分类号： G01R31/02 ,  G01R31/12 ,  G01R27/26

CPC分类号： G01R31/021 ,  G01R31/025 ,  G01R31/1272

摘要： A charging current flows through an insulation for insulating two conductors of an electric apparatus by applying an alternate current voltage thereto. A direct current component of the charging current is detected, and is amplified by biasing a direct current voltage to the alternate current voltage. An insulation deterioration of the electric apparatus is determined by an absolute value of the amplified direct current component.

摘要翻译： 充电电流流过用于通过向其施加交流电压来绝缘电气设备的两个导体的绝缘体。 检测充电电流的直流分量，并通过将直流电压偏压到交流电压来放大。 电气设备的绝缘劣化由放大的直流分量的绝对值决定。