| 摘要 |
PURPOSE:To prevent a power converter from becoming an overvoltage or insufficient voltage by setting the magnitude of a DC current to a value immediately before becoming the specified value when the DC voltage becomes larger by the specified value than the set value, thereby reducing the variation in the torque. CONSTITUTION:When a regenerative current becomes the DC input current or higher of a converter. A switch circuit 9 becomes OFF, and a speed deviation signal DELTAS which has been added to the input of a speed deviation amplifier 10 so far is interrupted. Since the amplifier 10 has an integrating item, it outputs a torque command signal taup immediately before the speed deviation DELTAS becomes zero even when the speed deviation DELTAS becomes zero. When switched from the regeneration to the motor drive operation, the DC voltage V0 decreases, a signal of high level is outputted from a comparator 28, and a switch circuit 9 is set to OFF state. Accordingly, the DC voltage is prevented from decreasing similarly to the regeneration time. |
