| 摘要 |
A supply and control circuit for a DC motor having a separately excited field coil and armature, and a method of operating such circuit. The field coil and armature are supplied with current interrupters. Connected in parallel with the separately excited field coil of the motor there is a first thyristor which plays a "free wheeling" role. A second circuit connected in parallel with the field coil includes an inductance, a second thyristor, and a zener diode connected in series. A condenser is connected in parallel with the zener diode. A diode is connected in parallel with the inductance and first thyristor. The parts are so arranged that the firing of the principal thyristor of the current interrupter for the field coil of the motor, after the operation of braking the motor, produces the extinction of the second thyristor, thereby bringing the current flow in the field coil to zero. When the current flow has been restored to its positive value and attains a predetermined potential, the principal thyristor in the interrupter which supplies the armature of the motor with current may be fired to restore the functioning of the motor as a driving motor. |
