Synthesis of desired AC line currents in current-sourced DC-AC converters

The paper addresses the topic of the harmonic reduction and fundamental power factor correction for three-phase current-source (CS) DC-AC converters in a unified mathematical manner. Starting only from the analytical definition of the power characterizing the line current error signal, a closed-loop general optimal control strategy is deduced valid for different CS inverters and suitable to be implemented on-line via DSP-based controllers. The proposed strategy is applied to control the two most common types of CS inverters and related simulation results are presented. The reasoning accompanying these results and the developed strategy leads also to highlight and review the intrinsic differences between these types of converters, concerning the synthesis process of the desired line currents.