| 摘要 |
PROBLEM TO BE SOLVED: To provide a dielectric loss tangent measurement device that can measure with low-voltage AC and does not require connection/disconnection and a method therefor, and a power cable diagnosis device using the same and a method therefor.SOLUTION: In a dielectric loss tangent measurement device M and a method therefor, with respect to a sheath-grounded power cable maintained as laid in a grid and electrically separated from the grid, a resistance value R on the order of M&OHgr; or greater is measured with DC by a resistance measurement unit 1, an electrostatic capacitance C is measured with low-voltage AC by an electrostatic capacitance measurement unit 2, a dielectric loss tangent tanδis measured with low-voltage AC by a dielectric loss tangent measurement unit 3, and the dielectric loss tangent tanδis corrected on the basis of the resistance value R and the electrostatic capacitance C and the dielectric loss tangent tanδof the power cable is obtained by a dielectric loss tangent arithmetic unit 42. Then, in a power cable diagnosis device D and a method therefor, the degree of degradation of the power cable concerning insulation performance is obtained by a degradation arithmetic unit 43 on the basis of the dielectric loss tangent tanδof the power cable obtained by the dielectric loss tangent arithmetic unit 42.SELECTED DRAWING: Figure 8 |
