AC Motor Drives With a Reduced Number of Switches and Boost Inductors

This paper presents eight three-phase ac motor-drive configurations that operate with a reduced number of switches and boost inductors. Four of the configurations are single-motor drives, and four of the configurations are double-motor drives. The drives provide both bidirectional power flow and power-factor control. This paper presents the analysis and control strategy of the systems, including current control and pulsewidth-modulation strategy. In spite of using a reduced number of components, the dc-link voltage and the machine currents of some of the proposed configurations are not much larger than the equivalent values of the conventional configurations. These drive systems are suitable for applications where the size of the system is a critical factor. The experimental results demonstrate the feasibility of the proposed topologies.