Loss minimization of boost mode dual inverter drive system

A dual inverter drive system is proposed, which is capable of boosting the phase voltages applied to an open-winding electric machine. A zero sequence current at the third harmonic of the intended output frequency is added to increase the supply voltage of one inverter, thereby extending the operating range of the machine. The need for a reactive current to weaken the machine field is avoided as a result. A method is introduced for simultaneously optimizing the inverter voltages and minimizing the required boost current, to maximize the overall system efficiency. The analysis is explained and verified by simulation.