Electronic Journal of Differential Equations (Jul 2019)
Existence of quasi-periodic invariant tori for coupled van der Pol equations
Abstract
This work focuses on the existence of quasi-periodic invariant tori for coupled van der Pol equations. Using averaging method, a series of reversible transformations and KAM techniques, we prove that there exist quasi-periodic invariant tori for most parameters. The results in this article can be regarded as a generalization of those in [22].