| Abstract |
This paper presents a novel direct frequency converter structure controlled by a cooperative-predictive algorithm. The converter operates with a maximum load current distortion of 4 %, and keeps its commutation frequency
below 550Hz. These facts, combined with the overall ac-ac voltage gain of3.5l, makes the proposed converter Suitable for medium voltage adjustable speed drives. 1bis is further motivated by the use of the multiple secondary windings transformer, and the converter's own structure, which eliminate the need for the step-up transformer required by conventional medium voltage drives to supply the motor load. Consequently, the transformer windings V A rating is
reduced by 50 %. The transformer employed also produces a multi-pulse operation towards the utility side, improving the converter's input current distortion and input power factor. |
