Maximum Linear Modulation Range Analysis of SVPWM for Dual Three-Phase PMSM Under Torque Sharing Control

The development of multi-three-phase motor drives has taken an accelerating pace in the past few years, and torque sharing control has been a topic of many classical studies. However, the motor with unequal torque sharing makes the space vector pulsewidth modulation (SVPWM) easier to enter the nonlinear region. This paper conducts a comprehensive analysis regarding the maximum linear modulation capability of three representative SVPWM strategies for dual three-phase permanent-magnet synchronous motor (DTP PMSM) under unequal torque sharing control. First, the features of the reference voltage vectors under unequal torque sharing, especially the vector phase relationship affected by motor parameters and working conditions, are revealed. Then, based on the features of the reference voltage vectors, the maximum linear modulation range for different SVPWM strategies under unequal torque sharing is analyzed in detail. Through this study, the maximum potential of torque sharing for DTP PMSM under the corresponding SVPWM strategies can be explored without nonlinear modulation. Finally, the simulation results are provided to validate the correctness of this analysis.