Research on harmonic current suppression of three-phase four-wire power conversion system

Abstract

The harmonic current of the three-phase four-wire gridconnected power conversion system (PCS) will be increased due to gridside harmonics and neutral loop. To solve these problems, the three-phase four-wire I-type three-level converter is applied as the topology in this paper to study the harmonic current suppression of the grid-connected PCS. A compound control strategy with the proportional integral (PI) and repetitive controller in parallel is presented and the interaction between the parameters of the compound controller is analyzed. The comparative research is carried out from the theoretical perspective of model analysis, and a controller optimization scheme is proposed. Finally, under the grid and neutral current waveform quality of simulation and experiment, the correctness and effectiveness of the proposed scheme is verified.