Stability analysis for multi-parameter linear periodic systems

This paper is devoted to stability analysis of general linear periodic syst ems depending on real parameters. The Floquet method and perturbation techn ique are the basis of the development. We start out with the first and high er-order derivatives of the Floquet matrix with respect to problem paramete rs. Then the behaviour of simple and multiple multipliers of the system wit h a change of parameters is studied. Weak and strong interactions of multip liers in the complex plane are treated separately. The presented theory is exemplified and discussed.