Circuits with linear dynamic elements and nonlinear resistors can be solved iteratively using the method of equivalent sources, by replacing the nonlinear resistors with controlled sources having constant resistance throughout the iterations. The final values of the state variables appear as affine functions of their initial values and only the additive term changes iteratively. By imposing a periodicity condition the initial values of the state variables are obtained by solving a linear system of equations in which the system matrix remains unchanged during each iteration and only the right hand side is modified. This matrix is inverted only once before the iterations begin

Keywords: Steady state, Nonlinear circuit, Equivalent source method