This paper presents two new approaches for linguistic modeling which are suitable for stability analysis of linguistic models. The first approach, which is named called Infinite Place model, is described by modified fuzzy Petri net and uses a new place definition based on physical infinity state. This method has some practical difficulties. In order to overcome practical difficulties, variation model is presented. The paper presents some definitions and a necessary and sufficient condition for linguistic fuzzy system stability. This stability analysis method is verified using a benchmark network simulation.