DIRECTION DISCRIMINATING DEVICE FOR FAULTY CURRENT AND FAULTY SECTION LOCATING METHOD FOR TRANSMISSION LINE USING DEVICE THEREOF

摘要

PURPOSE:To selectively detect a faulty current flowing to one direction only of an overhead ground line at the optional position on a transmission line by providing an orientating element for detecting the direction of faulty current, signal holding device and current discriminating device. CONSTITUTION:The faulty current on the overhead ground line 2 is detected by a CT 5 and supplied to the orientating elements LED 12A, 12B, the current directions of which are inverted, to emit one of them. The light emitting signal is received by a corresponding light receiving element 13A or 13B, and the output signal is held in the corresponding signal holding device 14A or 14B. The output of the holding device is supplied also to an input prohibiting terminal of each other holding device and the output signal is inputted to the discriminating device 18. By the discriminating device 18, the output of an exclusive OR circuit 16 and the output of the signal holding device 14A are inputted to an exclusive AND circuit 17 to surely detect only the faulty current in either one direction flowing to the overhead ground line 2. Since the direction of faulty current is reversed at the faulty point making as a boundary, the faulty section can be very easily located when these devices are provided on the transmission line with a specified interval.