A new iterative method for the global simulation of power electronic multi-converter systems

Power electronic converters generate harmonic currents that can disturb the network. To study the perturbations on the power line, it is necessary to perform a functional analysis via a global simulation. However, when the plant contains several static power converters feeding direct-current loads, global simulation becomes difficult, even impossible, because of the limitations of the software or the microcomputer used. There are no simulation tools that allow the quantitative evaluation of harmonic voltages and currents generated by a multistatic converter system. To fulfil this goal, the authors propose a new iterative analysis method for such systems and a new model for electronic power converters in terms of nonlinear current sources. This methodology has been included in a modified version of the ATOSECS software, renamed ATOSECM. The methodology is illustrated with an example of the use of ATOSECM on a personal computer for the study of two single-phase power converters connected to the same power line. A comparative analysis between global simulation (ATOSECS) and the new method of simulation (ATOSECM) is also presented for the case of two three-phase full-wave thyristor converters, with different firing angles and loads.