In this paper there is presented a procedure in which the nonlinear resistive elements are replaced by voltage or current generators whose sources are corrected, in an iterative manner, function of the voltage or of the current corresponding to the terminals. The resistances of the generators do not modify along the iterations and they can be chosen such that the three-phase network to be balanced, from its passive elements point of view. The harmonic analysis of the network is performed, by decomposing it into a direct, inverse and homopolar succession. By applying the proposed procedure, it results a spectacular reduction of the circuit’s complexity. After determining the voltages and the currents at the terminals of the generators, their values, in time domain, are being computed and the sources are corrected. Then, the complex images are obtained, and the next iteration is applied. It results immediately the content of the harmonics and therefore the power quality.

Keywords: Three-phase nonlinear networks, Fix point method for nonlinear controlled sources, Direct, inverse and homopolar succession network decomposition