Numerical analysis of the steady-state response of nonlinear circuits using the trigonometric collocation method

A general formulation of the trigonometric collocation method (TCM) for finding the steady-state response of nonlinear circuits, both autonomous and forced, is given. It is shown that the approximating equations of the TCM, which are formulated in the time domain in terms of the samples of the sought oscillation, are essentially equivalent to those resulting from the harmonic balance method (HBM), and are obtained avoiding the transformations between the frequency domain and the time domain, and vice versa, needed in the HBM. The TCM is also related and compared to other sample balance techniques, showing the superiority of the presented method through its application to some typical nonlinear circuits