Novel modified phase-shift modulation strategy for isolated AC–DC power converters

LLOMPLAT, MARCELO; BOSSO, JONATHAN E.; CARBALLO, ROBERTO E.; GARCÍA, GUILLERMO O.

IET Power Electronics

Institution of Engineering and Technology

Año: 2020 vol. 13 p. 1022 - 1032

1755-4535

Different power converter topologies are used to perform the energy exchange between an AC grid and a DC source belonging to a hybrid electric micro-grid. A single-phase single-stage isolated AC-DC power converter is one of them.Moreover, this power converter can operate under different modulation strategies. The phase-shift modulation (PSM)strategy is capable of varying the phase between the voltages applied to the high-frequency transformer terminals of the power converter in order to control the energy flow in both directions. Based on the PSM strategy, this study presents a novel modified PSM strategy capable of controlling the power flow in both directions and obtaining a current with low total harmonic distortion and a power factor close to 1 for the entire operating range on the AC side. Considering the novel modulation strategy to be proposed, a comparison of three PSM-based modulation strategies was carried out taking into account the total harmonic distortion of current injected into the AC grid, the power factor and the average power transferred. A theoretical analysis was carried out and the results obtained were validated by means of experimental results.© The Institution of Engineering and Technology 2019.