Black-Box Modelling of Low-Switching-Frequency Power Inverters for EMC Analyses in Renewable Power Systems

Electromagnetic interference (EMI) from renewable power systems to the grid attracts more attention especially in low-frequency range, due low switching frequency of high-power inverters. It is significantly important derive EMI models inverters as well develop strategies suppress related conducted emissions. In this work, black-box modelling applied a three-phase inverter system, by implementing an alternative procedure identify parameters describing active part model. Besides, two limitations are investigated. The first regards need for system satisfy linear and time-invariant (LTI) assumption. influence assumption on prediction accuracy analysed with reference zero, positive negative sequence decomposition. showing that predictions positive/negative highly influenced assumption, unlike those zero sequence. second limitation possible variation mains impedance which not satisfactorily stabilized at outside operating range standard line stabilization networks.