Control system of electric-car driving motor

PURPOSE: To improve adhesive performance by estimating the current flown in a motor to obtain a current-feedback value and avoiding the effects of slips on a current-control system. CONSTITUTION: Power is supplied to driving motors 6AW6D via a transformer 3 and a power converter 4, and driving wheels 7AW7D are driven. At the same time, the secondary wheel 70 is driven by a motor 60, whose capacity is smaller than those of the motors 6AW6D and characteristics are similar. The current flown in the motor 60 is detected by a detector 10, wherein a current feedback signal I f is formed through a coefficient device 61. The feedback signal I f is compared with a current-command signal I p in a comparator 11, and the difference signal V p controls a voltage-control device 12. Since the capacity of the motor 60 is so selected that the secondary wheel 70 does not slip even though the driving wheels 7AW7D slip, the current-feedback value I f does not decrease, and the large slip can be prevented. COPYRIGHT: (C)1980,JPO&Japio