This paper presents a methodology, based on both Floquet theory and the participation matrix concepts, aimed at characterization of a time-periodic system in terms of its poles location in the complex plane. The participation matrix allows to find which poles are the most influenced by certain state-variables. The proposed methodology can be utilized as an auxiliary tool for parameter design, stability assessment, and for post-event analysis of time-periodic systems. The proposed methodology is readily applicable to distributed generation systems. A case study involving a stand-alone wind-photovoltaic battery system is presented to support this statement. (c) 2021 Elsevier Ltd. All rights reserved.