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H. Ertl, J.W. Kolar, F. Zach:
"A Constant Output Current Three-Phase Diode Bridge Employing a Novel Electronic Smoothing Inductor.";
Talk: PCIM, D, Nuernberg; 1999-06-22 - 1999-06-24; in: "Proceedings of the 41st International Conference on Power Conversion,", (1999), 645 - 651.

Abstract - The paper presents a novel extension of a conventional three-phase diode bridge rectifier with capacitive smoothing of the output voltage which improves the power factor at the AC input and which reduces the ripple current stress on the smoothing capacitor. The basic concept of the proposed system is the arrangement of an active element between the output of the diode bridge and the smoothing capacitor which is controlled in a way that it "emulates" an ideal smoothing inductor. With this the input currents of the diode bridge showing usually high peak amplitudes are transformed into a 120° rectangular shape which ideally results in a total power factor of 0.955. The active element mentioned before is realized by a low-voltage switch-mode converter stage of small power rating as compared to the output power of the rectifier.
Starting from a discussion of the drawbacks of three-phase diode rectifiers with capacitive smoothing, the paper describes the basic concept, the stationary operation and dimensioning guidelines, the design of the control and the transient behavior of the proposed system. Finally, results of measurements taken from a laboratory model are presented.