Slave station, surge detection time locating method, failure location system, and failure location method

摘要

PROBLEM TO BE SOLVED: To accomplish a slave station and a surge detection time evaluating method providing an accurate surge detection time without any increase of an erroneous detection frequency and a failure point locating system and a failure point locating method evaluating a failure point precisely. SOLUTION: In a slave station arranged in a electrical transmission and distribution wire path, a detection time of a surge voltage due to a failure caused in any point in an electrical transmission and distribution wire path is evaluated by a surge detection time evaluating method. A surge recognition level set above a noise level for serving as a reference level for recognizing a surge and a surge waveform starting level set below the surge recognition level for serving as a reference level for deciding a surge waveform starting point are decided previously. A past voltage waveform preceded for a fixed time from the present time is stored and always renewed. When a voltage exceeds the surge recognition level, the stored waveform is checked back to the past, and the time when the surge waveform starting level is exceeded at the first time is determined as a surge detection time.