| 摘要 |
<p>PURPOSE:To effectively prevent the occurrence of a reidling of a railway rolling stock by maintaining the state that the current of a motor is reduced for the prescribed period of time even if an idling is finished when an idling once occurs. CONSTITUTION:When an idling occurs in a rolling stock, a differential voltage is produced between voltage dividing resistors 51 and 52, is detected and an idle relay 6 is operated. Thus, an OFF delay timer 7 is operated, and an idle detection signal is applied to a chopper controller 8. The controller 8 thus reduces the current flow rate smaller than the ordinary value, a thyristor 4 is fired by the output control signal from the controller, thereby reducing the current of a main motor. When the idling is then finished, the relay 6 is reset, and the timer 7 is deenergized. In this case, the timer 7 continues (holds) the operation for the prescribed period of time, and the idle detection signal is continuously applied to the controller 8. In this manner, the current of the main motor is maintained in the reduced state for the predetermined period. Accordingly, no reidling occurs.</p> |
