Reduced switch-count six-phase AC motor drive systems without input reactor

In this paper, two reduced switch-count six-phase ac motor drives are investigated. The first configuration considered has six legs (configuration 6L), and the second one has five legs (configuration 5L) and uses the capacitor dc-link midpoint connection. Both configurations operate without- input reactors and provide both bidirectional power flow and power-factor control. Both 60 degrees and 30 degrees six-phase induction-machine windings are employed. Operating principles and control strategies for the topologies are presented. The proposed configurations are compared with the full-bridge (nine legs) and the half-bridge (six legs) topologies, which use the capacitor dc-link midpoint connection. These drive systems are suitable for applications where the size of the system is a critical factor. Experimental and simulation results are presented.