JPS6432181A - Ground discharge measuring method - Google Patents

Abstract

PURPOSE:To estimate a ground discharge position on a power transmission line accurately accurately and immediately at a specific monitor station by forming a return signal loop and installing couples of sensors at plural positions of the going and return loop parts opposite each other. CONSTITUTION:An overhead earth-wire 1 with an optical fiber is supported on steel towers 2 and provided with couples of sensors 3a, 3b, 3c, 3d... such as Pockels elements which detect a lightning current at the respective positions of the steel towers 2. The sensors 3a, 3c... among said sensors are connected to the going loop part 4A composed of an optical fiber in series and other sensors 3b, 3d... are connected to the return loop part 4B composed of an optical fiber in series to form the signal loop 4. Then when ground discharge occurs to the power distribution line, a couple of sensors on both sides of the position where the ground discharge occurs operate to send a couple of signals to the loop parts 4A and 4B. The ground discharge position is estimated from the time width between the couple of signals and the time width between adjacent signals among couples of signals generated at the loop parts 4A and 4B.