Phase Displaced SVPWM Technique for Five-Phase Open-End Winding Induction Motor Drive

The three-level dual-inverter connected to Five-Phase Open-End Winding Induction Motor (FPOEWIM) drive can have either isolated DC bus or a single DC bus. The single DC bus configuration is advantageous over the former, since, it avoids the use of bulky isolation transformers. But this configuration adds the zero-sequence current flowing through the common DC bus and the motor phase windings. This paper proposes a SVPWM technique to eliminate the zero-sequence current and also the lower order harmonic currents flowing through the motor phases. The proposed technique operates the dual-inverter using the reference voltage vectors of both the inverters which are phase displaced by 18 degrees. This technique uses the nearest possible space vector locations to realize the resultant reference voltage vector. This could reduce the ripple content in the motor phase current, which in turn reduces the torque ripple. The proposed SVPWM technique not only uses the space vector locations with zero common-mode voltage but also the other locations where the common-mode voltage is not equal to zero. This may lead to the presence of common-mode voltage ( approximately 8% of the fundamental), but eliminate the zero-sequence current. The proposed PWM technique along with the system modeling is explained in brief and the simulation results are presented.