Ways to improve the efficiency of the electric drive of cold rolling-mill

Different ways to improve energy efficiency of electric drives of cold reducing mill are considered. Studies based on mathematical modelling result in quantitative evaluation of the energy saving. With the example of the KhPT-450 cold reducing mill, the dependence of the root-mean-square current of the motor armature of the main stand drive on the cutoff frequency of the speed loop has been obtained. The paper considers possible energy savings by means of preliminary motor field reduction before the rolling duty cycle. It defines points of field-reduction pulse supply and termination that are optimal for power saving. The paper specifies conditions for substantiation of correlated parameters of the dynamic units and changing operation schedule of the electric drive, thus, providing the greatest reduction of losses in the main drive of the cold reducing mill. These measures under consideration are aimed to improve energy efficiency of electric drives of these mills and reduce power consumption for a rolling cycle by 20-25 %.