AC-AC DRIVE SYSTEMS WITH OPEN-END FIVE-PHASE MACHINE AND SIXTEEN-LEG DC-LINK CONVERTER

This paper presents two ac machine drive systems based on three-phase to five-phase ac-ac converters and open-windings five-phase machine. The drive systems are suitable to applications in which high power, performance and reliability are required using low power and voltage switches and low dc-link capacitor voltages. The configuration I employs an input transformer with two secondary taps at the grid side, two three-phase three-leg converters and one ten-leg converter (totalling sixteen legs). The configuration II employs a low-power series transformer at the grid side, two three-phase three-leg converters, and one ten-leg converter. Both configurations permit to reduce the power and voltage ratings of power switches and also the dc-link capacitor size. The paper presents the comprehensive models of the proposed systems, modulation strategies and a general comparison with conventional configuration. Simulated and experimental results are presented.