DC solution of nonlinear state-space equations in circuit analysis

A reliable algorithm is described for calculation of the initial condition state vector as formulated in network transient analysis programs. The algorithm is based on a combination of Davidenko's parameter-stepping method and Broyden's method. It has been found to give fast reliable solutions even in cases for which most Newton-Raphson methods fail to converge, as well as for circuits that produce singular systems of equations at the starting point.