Generalization of Wye and Delta auto-connections: Analysis of voltages and currents

• Autor(a) principal: Da S. Oliveira, Priscila [UNESP]
• Data de Publicação: 2010
• Outros Autores: Fernandes, Rodolfo C. [UNESP], De Seixas, Falcondes J. M. [UNESP]
• Tipo de documento: Artigo de conferência
• Idioma: eng
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://dx.doi.org/10.1109/INDUSCON.2010.5739916; http://hdl.handle.net/11449/72045
• topic: 18-pulse; Ac-dc converters; As interfaces; Current harmonics; DC load; Design procedure; Differential connection; Differential topology; Input voltages; Load voltages; Multi-pulse rectifiers; Phasor diagrams; Power factors; Total harmonic distortions; DC power transmission; Electric power factor correction; Mathematical models; Power converters; Retrofitting; Topology; Electric rectifiers

Multipulse rectifier topologies based on autoconnections, or differential connections, are more and more applied as interface stages between the mains and power converters. These topologies mitigate many low-order current harmonics in the utility, reducing the THD (total harmonic distortion) and increasing the power factor. This paper presents a mathematical model based on phasor diagrams, that results in a single expression able to unify all differential topologies connections (Delta and Wye), for both step-up or step-down autotransformers, for 12 and 18-pulse AC-DC converters. The proposed family of converters can be designed for any relationship between the input voltage and the load voltage. An immediate application would be the retrofit, i.e. to replace a conventional rectifier with poor quality of the processed energy by the 12 or 18 pulses rectifier with Wye or Delta-differential connection. The design procedure, simple and fast, is developed and tested for a prototype rating 6 kW and 250 V on the DC load © 2010 IEEE.