Low-Harmonic-Input Three-Phase Rectifier With Passive Auxiliary Circuit: Comparison and Design Consideration

A novel passive correction approach to improve the input currents of a conventional three-phase rectifier with dc-side C filter is studied in this paper. By adding an inductor and capacitor passive auxiliary circuit to the ac side of the rectifier, good mains behavior would be achieved. A family of low-harmonic-input three-phase rectifiers with passive auxiliary circuit is derived. From the comparative analytical results in operation principle, auxiliary circuit design, characteristic discussion, and simulation results, some important conclusions are drawn. Experimental results from the prototypes built in the laboratory with different specifications are shown to confirm the validity of the analysis and the feasibility of the proposed approach.