| 摘要 |
PROBLEM TO BE SOLVED: To prevent a ferro-resonance phenomenon in an iron core using apparatus caused by an electrical shock occurring when a circuit breaker present on the upstream side of a zero-phase voltage transformer is turned on.SOLUTION: In a power substation where a three-phase AC electric line 2 connected to the secondary side of a transformer 1 is disconnected and reconnected by a power-receiving circuit breaker 6, a zero-phase voltage transformer 14 for extracting voltage information is connected to the three-phase AC electric line 2, and a section between the three-phase AC electric line 2 and ground in the vicinity of the zero-phase voltage transformer 14 is grounded to earth by using a three-phase capacitor function device 13 which connects capacitor function elements (e.g., a surge absorber) for each phase in the shape of a star and grounds the neutral point to earth. |
