An approach to harmonic current-free AC/DC power conversion for large industrial loads: the integration of a series active filter with a double-series diode rectifier

This paper proposes a new harmonic current-free ac/dc power conversion system characterized by the integration of a small-rated series active filter with a large-rated doubleseries diode rectifier.The dc terminals of the active filter are directly connected in parallel with those of the diode rectifier, thereby forming a common dc bus.The active filter enables the diode rectifier to draw three-phase sinusoidal currents from the utility.In addition, it can provide the supplementary value-added function of regulating the common dc-bus voltage to a limited extent of 65%, slightly increasing the rms voltage rating, but not increasing the peak voltage rating.Experimental results obtained from a 5-kW laboratory system verify the practical viability and cost effectiveness of the proposed system. Index Terms-Diode