| 摘要 |
When a plurality of shunt motors connected in parallel are used for driving an electric railcar the, differences in the characteristics of the motors introduced during the manufacturing thereof causes the armature currents to vary greatly even when they are running at the same speed. To control the field current by means a single device, therefore, the armature currents must be corrected by armature choppers. In order to fully recover the kinetic energy possessed by the electric railcar, the present invention automatically corrects for the difference in the characteristics of the shunt motors so that the required braking force is uniformly borne by each of the shunt motors. |
