| 摘要 |
PURPOSE:To ensure a safe passage of a dead section by a method wherein an electromagnetism detecting unit is provided forward of a pantograph electromagnetically detecting if an overhead line carries a voltage and, if not, sending out a signal to decrease a power source output. CONSTITUTION:An electromagnetism detecting unit 30 is installed forward of a pantograph 2 to detect through the space whether a power transmission line over the roof of a vehicle 31 is supplied with a voltage. With the vehicle entering a dead section 1, the electromagnetism detecting unit 30 detects no voltage and yields a signal reducing the voltage outputted by a phase shifter, which in turn reduces the supply of the overhead line power to the electric motor vehicle. This simple circuit ensures the safe passage of the dead section. |
