| 摘要 |
PROBLEM TO BE SOLVED: To transmit system observation data in a slow mode under a normal conditions without interference, and in a fast mode, only when an interference occurs. SOLUTION: System phenomenon observing apparatuses 20 to 23 in respective substations normally transmit system observation data in the slow mode, and upon receiving transmission mode changing command data from an upper control section 30, switch the transmission mode from the slow mode to the fast mode. The upper control section 30 transmits the transmission mode changing command data upon receiving harmonic interference data from any of the system phenomenon observing apparatus. Thus, the control section 30 can receive continuous and sufficient amount of data, while avoiding line congestion only when analyzing possible causes of harmonic interference or the like. |
