This paper addresses the stability and stabilization problems of rolling mill main drive systems with time delay. The complete stability problem with respect to the delay parameter is investigated for linearized systems with and without control. The systems are first formulated in the characteristic function form, and the corresponding complete stability problem is introduced. By employing the frequency-sweeping approach, the complete stability properties are systematically analyzed. As a result, several analytical properties related to the local asymptotic behavior of critical imaginary roots are derived. Finally, numerical examples demonstrate that the whole stability set with respect to delay can be accurately determined.
Fan et al. (Mon,) studied this question.