| 摘要 |
PROBLEM TO BE SOLVED: To determine after which branch point of a branch circuit a fault point is present, and to locate the position of the fault point more accurately.SOLUTION: Resonance frequency calculation means 18 calculates a resonance frequency of ground-fault current of a transmission/distribution line. First fault point distance calculation means 19 calculates a first fault point distance from a transformer to a fault point. Second fault point distance calculation means 20 calculates a second fault point distance from the terminal of the transmission/distribution line to the fault point. Based on the first fault point distance, the second fault point distance, and a transmission/distribution line distance from the transformer to the terminal of the transmission/distribution line, branch point distance calculation means 21 calculates a distance error caused by fault point inductance to calculate a branch point distance from the transformer or the terminal of the transmission/distribution line to a branch point of a branch circuit when the fault point occurs at the branch circuit of the transmission/distribution line, and calculates a fault point distance from the transformer or the terminal of the transmission/distribution line to the fault point when the fault point occurs at places other than the branch circuit. |
