| 摘要 |
PURPOSE:To shorten the starting time of an emergency sealing oil pump by connecting a current chopper which uses a semiconductor switch in parallel with a starting resistor. CONSTITUTION:When a start signal is applied, a contactor 2 is first closed to flow a starting current through a starting resistor 5 to an armature 7 to start a DC motor. Then, as a time is elapsed, a signal is supplied to a contactless switch 3 to increase the rotating speed, and to reduce an armature current. Thus, the contactors are sequentially closed, and when arriving at the prescribed speed, the start is completed. Thus, an emergency sealing coil pump system which has high rise of a motor, good backup and high reliability can be provided. |
