| 摘要 |
PURPOSE:To make it possible to detect DC grounding point with high accuracy, by measuring an grounding resistor current by frequency analysis and a phase analytical program. CONSTITUTION:When ground accident is generated in a load wire 6, a DC earth current is converted to an intermittent earth current (Io) of 10Hz by a neautral point interruptor 3 in order to detect grounding point. The intermittent earth current (Io) is detected by a search coil 7 to be inputted to a computer and, at the same time, earth voltage Eo is also inputted to the computer while an earth grounding resistor current IR is calculated on a real time and indicated by an indicator 9 to measure the grounding resistor current IR. The grounding point is detected by deciding said grounding point from the measured value of the grounding resistor current IR. |
