SIAM Journal on Control and Optimization, Vol.48, No.8, 5583-5605, 2010
AN EIGENVALUE PERTURBATION APPROACH TO STABILITY ANALYSIS, PART II: WHEN WILL ZEROS OF TIME-DELAY SYSTEMS CROSS IMAGINARY AXIS?
This paper presents an application of the eigenvalue series developed in Part I [J. Chen et al., SIAM J. Control Optim., 48 (2010), pp. 5564-5582] to the study of linear time-invariant delay systems, focusing on the asymptotic behavior of critical characteristic zeros on the imaginary axis. We consider systems given in state-space form and as quasi-polynomials, and we develop an eigenvalue perturbation analysis approach which appears to be both conceptually appealing and computationally efficient. Our results reveal that the zero asymptotic behavior of time-delay systems can in general be characterized by solving a simple eigenvalue problem, and, additionally, when described by a quasi-polynomial, by computing the derivatives of the quasipolynomial.
Keywords:time-delay systems;quasi-polynomials;characteristic zeros;eigenvalue perturbation;generalized eigenvalues and eigenvectors