D. Carlton

Multi-level, uni-directional AC-DC converters, a cost effective alternative to bi-directional converters

A uni-directional, multi-level power converter family, to which the Vienna rectifier belongs, is proposed. Its features are studied, and a cost-performance analysis is also presented.

Average current space vector technique for the analysis of three-phase power factor correction circuits operating in discontinuous conduction mode

A novel space vector method which uses average currents over a switching cycle is proposed for the analysis of three-phase power factor correction circuits operating in discontinuous conduction mode. The technique is applied to a family of circuits with switches on the AC-side. The improvement in performance and wider flexibility of operation over DC-side circuits are shown.

Harmonic reduction in the 3-phase 3-switches boost-delta power factor correction circuit operating in discontinuous conduction mode

A harmonic injection technique which reduces the line frequency harmonics of the boost-delta three-phase three-switches power factor correction circuit is proposed. A comparison is made with the boost-star circuit, with and without harmonic injection. The switching frequency harmonics present in the current of passive components of circuits operated in discontinuous conduction mode are determined analytically.

Continuous conduction mode operation of a three-phase power factor correction circuit with quasi tri-directional switches

The quasi tri-directional switch is proposed for three-phase AC-to-DC conversion. It consists of three quasi bi-directional switches, such as IGBTs with anti-parallel diode, star-connected. The implementation in the three-phase boost power factor correction circuit operating in continuous conduction mode is analyzed using the space vector technique. The increase in the number of space vectors available renders new modulation features to the circuit.

SEPIC 3-phase 3-switches power factor correction circuit operating in discontinuous conduction mode

This paper proposes a new 3-phase 3-switches power factor correction (PFC) circuit based on three single ended primary inductor converter (SEPIC) networks placed on the AC side. The switches are bi-directional. The discontinuous conduction mode (DCM) operation is analyzed, where the inductor and capacitor currents reach zero in every switching cycle. The overall performance is shown, guidelines for design optimization are given and the benefits and tradeoffs of the circuit are presented.

Skip-cycle modulation of three-phase boost power factor correction circuits operating in discontinuous conduction mode

A new modulation technique is proposed for the three phase full- and half-bridge operating as power factor correction in discontinuous conduction mode. The average-current and voltage space vectors are in phase only as an average over several switching cycles. The harmonics can be kept within the requirements of standard EN 61000-3-2 for the whole specified power range.