| 20090267554 | DRIVING APPARATUS OF ELECTRIC MOTOR FOR REDUCTION ROLL - There is provided a driving apparatus of an electric motor for a reduction roll that can improve maximization of rolling performance and a speed decrease amount by making maximal use of torque that various electric motors can generate during material entry. The apparatus includes an upper electric motor speed controller that acquires an upper electric motor torque current reference based on a deviation between an actual upper electric motor speed and an upper electric motor speed reference; an upper electric motor torque current limiter and current controller that control torque of the upper electric motor; a lower electric motor speed controller that acquires a lower electric motor torque current reference based on a deviation between an actual lower electric motor speed and a lower electric motor speed reference; a lower electric motor torque current limiter and current controller that control torque of the lower electric motor; and a torque distribution controller provided between the upper and lower electric motor speed controllers and the upper and lower electric motor torque current limiters, that compares the upper and lower electric motor torque current references and a torque current limit value, and when either the upper or lower torque current reference exceeds the torque current limit value, adds that exceeding amount to the other torque current reference. | 10-29-2009 |
