• multi-phase voltage source inverters;
  • pulse-width modulation;
  • multi-dimensional space


Space vector PWM (SVPWM) is a popular and well-known technique for standard three-phase drives, which has been extended recently to multi-phase voltage source inverters (VSIs). Several SVPWM techniques, which utilize the principle of vector space decomposition (VSD), have been developed for various operating modes. The VSD approach inherently relies on considerations in two-dimensional (2-D) subspaces, while SVPWM for a multi-phase VSI is in essence a multi-dimensional problem. Hence, an alternative approach to SVPWM, which is based on the direct multi-dimensional space consideration in the space vector selection process rather than on space vector selection in 2-D subspaces obtained by vector space decomposition, has been recently introduced. Good performance has been identified, but the method is complex and difficult for the real-time implementation. This article therefore combines multi-dimensional SVPWM approach with off-line calculations to achieve required output voltage generation under non-sinusoidal and/or unbalanced voltage requirements, which represent the most challenging operating conditions from the point of view of the vector selection for PWM. As a consequence, the implementation becomes rather simple in standard DSPs. The performance of the algorithm is verified by simulation and experimentation. © 2009 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.