Black-box Modeling of Converters in Renewable Energy Systems for EMC Assessment: Overview and Discussion of Available Models

The development of renewable energy systems interfaced with the grid by power electronic converters leads to increasing issues of electromagnetic coexistence between power and communication lines, as well as severe power quality issues, such as total harmonic distortion at the consumer side. Therefore, high-frequency modeling of renewable energy systems is of great importance to guide the design and development of distribution networks involving renewable sources. Owing to system complexity, black-box modeling approaches offer more advantages than traditional circuit modeling, as far as electromagnetic compatibility (EMC) analysis and filter design are the targets. In this study, different black-box modeling techniques for power converters are introduced and systematically analyzed. First, the general theory of black-box modeling is explained. Subsequently, three different modeling approaches are compared in terms of accuracy and the required experimental setup. Finally, the possible limitations of black-box modeling of power converters are investigated and discussed.