DETECTING METHOD FOR GENERATION OF FAILURE IN TRANSMISSION LINE, TRANSMISSION METHOD FOR INFORMATION ON GENERATION OF FAILURE AND LOCATING SYSTEM FOR FAILURE SECTION

摘要

PROBLEM TO BE SOLVED: To obtain a detecting method in which the generation of a failure can be detected even when a ground-wire current is not increased in the failure by a method wherein the deviation value between a present instantaneous value and an instantaneous value at the immediately preceding cycle of an AC cycle is found, instantaneous values are totaled retrospectively and a moment in which their totaled value exceeds a threshold value is detected as a moment in which the failure is generated. SOLUTION: An instantaneous value which is converted by an A/D converter 31 is converted into a light signal by an E/O conversion part 32 so as to be converted into an electric signal by an O/E conversion part 44. The instantaneous value is stored in a first memory 46. A stored instantaneous value which is at an immediately preceding cycle from a present cycle is fetched, and the deviation value between the present instantaneous value and the instantaneous value at the immediately preceding cycle is stored temporarily in a second memory 47. Values which are stored in the second memory 47 are totaled so as to retrospect prescribed sampled values from the present instantaneous value. When a failure is generated, a difference is generated by the present instantaneous value and the instantaneous value at the immediately preceding cycle. The sum of the absolute values of differences becomes larger than a prescribed threshold value. Even when a system is a complicated line and a ground-wire current is not changed largely in a failure, the deviation of a waveform is evaluated, and the generation of the failure can be detected.