Overview of State of the Art of Reduced Parts Converter Topologies for Adjustable Speed Drives

In this paper, various reduced parts converter topologies and control strategies for power factor correction and motor control are reviewed and systematic design methodology is developed. From this investigation, the converter topologies could be mainly categorized into cascade type and unified type. The detailed operational principles are examined and the performance comparison is derived to illustrate merits and limitations of the converters. Simulation results are provided to help the better understanding of the theoretical description and several experimental results are presented on prototype induction motor and brushless dc (BLDC) motor drives, along with cascade and unified type converters.