In this paper we consider the problem of synthesis of equivalent circuits containing nonlinear electrical circuits, in general, any number of non-linear elements. The system of differential equations describing the linear non autonomous multi-pole after quasiequivalence transformations allows to synthesize an equivalent circuit of the multi-pole consisting of two-pole linear, nonlinear resistors, controlled voltage sources, etc. The question of replacing the series-connected voltage sources controlled by the operational amplifier, the implementation of linear and nonlinear two-pole resistors.