Method for diagnosing an insulation deterioration of a power cable
Abstract
Abstract 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.
Inventors
- 👤 Kenichiro Soma
- 👤 Kazuo Kotani
- 👤 Nobuju Takaoka
- 👤 Chuki Ikeda
- 👤 Moritada Marumo
Bibliographic Details
Claims Analysis
Total Claims: 4References Cited (Backward Citations)
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