A nine-switch inverter for driving two AC motors independently

This paper presents a nine-switch inverter that can drive two AC motors independently. Recently, as an inverter that can drive them independently, a five-leg inverter has been proposed. Ten switching devices are used for the five-leg inverter, whereas only nine are used for the nine-switch inverter. So, the nine-switch inverter has the merit that one switching device can be reduced compared to the five-leg inverter. Moreover, the maximum output voltage of the nine-switch inverter equals that of the five-leg inverter. In this work, we propose the structure of the nine-switch inverter and a modulation method for the same, and validate the nine-switch inverter by showing simulation results. (c) 2007 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.