A 40-Pulse AC--DC Converter Fed Vector-Controlled Induction Motor Drive

In this paper, a novel autotransformer for a 40-pulse ac-dc converter configuration is designed, modeled, simulated, and implemented to feed vector-controlled induction motor drive (VCIMD). The proposed converter consists of two paralleled ten-pulse ac-dc converters along with pulse doubling circuit at dc bus. Each ten-pulse ac-dc converter involves five-phase diode bridge rectifiers. It improves power quality at ac mains, and it meets IEEE-519 standard requirements at varying loads. A set of power quality indexes on input ac mains and dc bus for a VCIMD fed from 20-pulse and 6-pulse converters is also given to compare their performance. It is observed that input current total harmonic distortion (THD) of much less than 5% is possible with the proposed topology at varying loads.