Features of Excitation of Dynamic Processes in Group Electric Drives of Crimping Mills

The authors analyze the influence of variable technological loads on the main line of the rolling mill and present a mathematical model of dynamic processes in group electric drives of crimping technological machine units (rolling mills). The dependence of the moment of technological resistance on the speeds of the working rolls is shown to be determined by the formula that takes into account the peculiarities of the technological load. The study of the influence of variable technological loads on the main line of the rolling mill showed that an increase in the coefficient of friction on the upper roll is the most dangerous. It was found out that in these cases, there can be a significant mismatch of the speeds of the working rolls, and the drop in the moment of technological resistance on the upper roll is not compensated by the increase in the moment of technological resistance on the lower roll; therefore, self-oscillations, as well as unstable oscillation modes, are excited in the elastic links of the main line of the rolling mill.