Spice-oriented algorithm for analysis of coupled oscillators

For designing oscillatory circuit, it is important to simulate and search the characteristics. If we analyze a weakly nonlinear circuit, we often apply averaging method which is one of the approximate solving method. In this study, we combine the averaging method to Newton homotopy method and analyze a circuit by using Spice. By solving Newton homotopy method, we obtain multiple equilibrium points in a single Spice simulation. As an example, we analyze the property of two coupled van der Pol oscillators. By using our proposed Spice-oriented algorithm, we obtain three equilibrium points. The result shows us, our proposed method is convenient for search the equilibrium points in averaging method.