| 摘要 |
PROBLEM TO BE SOLVED: To solve the problem in a conventional digital protection relay system using a GPS signal, in which the abnormal conditions of a GPS receiving signal cannot be handled when a delay time differs as a transmission path differs in a round trip during communication with an adjoining protection relay device.SOLUTION: A difference in delay time from a sampling signal in the round trip to data reception is calculated and stored. At the abnormal conditions of the GPS signal, the sampling signals of adjoining protection relay devices are synchronized, based on the difference between each delay time acquired anew and the stored delay time. |
