A three-phase soft-switched isolated AC/DC converter without auxiliary circuit

Author

Norrga, Staffan ; Meier, Stephan ; Östlund, Stefan

Author_Institution

R. Inst. of Technol., Stockholm, Sweden

Volume

3

fYear

2004

Firstpage

1768

Abstract

An AC/DC converter topology comprises a voltage source converter (VSC) with capacitive snubbers and a 2-phase by 3-phase cycloconverter, connected by an MF transformer. By alternately commutating the two converters it is possible to achieve soft switching conditions for all of the semiconductor elements. Furthermore, it is shown that resonant commutation of the voltage source converter is possible by utilizing the cycloconverter in order to momentarily short-circuit the transformer terminals. This allows for soft commutation of the VSC down to zero load. Furthermore, the design and operation of a 40 kVA prototype converter system based on the studied concept is described.

Keywords

AC-DC power convertors; commutation; cycloconvertors; power transformers; resonant power convertors; snubbers; switching convertors; 40 kVA; AC-DC converter; MF transformer; VSC; capacitive snubber; cycloconverter; resonant commutation; semiconductor element; soft commutation; soft switching condition; voltage source converter; Analog-digital conversion; Circuits; DC-DC power converters; Filters; Isolation technology; Phase transformers; Power conversion; Snubbers; Switching converters; Switching loss;

fLanguage

English

Publisher

ieee

Conference_Titel

Industry Applications Conference, 2004. 39th IAS Annual Meeting. Conference Record of the 2004 IEEE

ISSN

0197-2618

Print_ISBN

0-7803-8486-5

Type

conf

DOI

10.1109/IAS.2004.1348710

Filename

1348710