Gopal Mondal Krishnamoorthy Sivakumar Rijil Ramchand K. Gopakumar Emil Levi A Dual Seven-Level Inverter Supply for an Open-End Winding Induction Motor Drive. 1665-1673 2009 56 IEEE Trans. Ind. Electron. 5 https://doi.org/10.1109/TIE.2008.2010159 db/journals/tie/tie56.html#MondalSRGL09