Sistemas estáticos de conversão c.a/c.a. com barramento c.c e número reduzido de componentes.

Abstract

Ac=ac dc-link converters are the most spread converter type in literature. They comprise an ac=dc and a dc=ac converter. The most common configurations are the full-bridges; however, reduced switch count high performance converters are continuously proposed and studied in literature to reduce cost in the power conversion system. In this work are proposed thirteen con¯gurations of reduced switch count ac=ac converter. It is proposed two single-phase to single-phase configurations; two three-phase to three-phase three-wire configurations; eight three-phase to three-phase four-wire configurations; and one three-phase to ¯ve-phase configuration aiming five-phase motor drive. The PWM strategies, control system and some performancefcharacteristics of all proposed configurations are also presented and compared to those of theffull-bridge and half-bridge configurations. When the input and output voltage frequencies are the same, as in UPS systems, some synchronization techniques are proposed to reduce the dc-link voltage. Those synchronization techniques are also applied to the full-bridge single-phase to single-phase converter and to the half-bridge three-phase to three-phase converter to reduce the ac currents through the dc-link.