| 摘要 |
PURPOSE:To shorten the idling time from the detection of slipping to the readhesion by reversely exciting one series motor group if a slipping occurs when the series motor group is cross-connected in parallel to operate as generators. CONSTITUTION:When a running electric railcar is decelerated by generatively braking, the first and second series motors in which armatures 11A, 21A and field windings 11F, 21F are connected in series are cross-connected in parallel, and a brake resistor 8 is connected between connecting points of the armatures and the field windings of the both motors. When a slipping occurs during generatively braking, contactors 27A, 27B are closed to reversely flow the current of the winding 21F, thereby abruptly increasing the brake torques of the both motors. If the reverse excitation is continued as it is, the brake torque is again increased after the slipping is eliminated. |
