Space Vector PWM for a Five-Phase VSI Supplying Two Five-Phase Series-Connected Machines

A five-phase two-motor drive system with series connection of stator windings and decoupled dynamic control has been introduced recently. The two-motor drive system is supplied from a single five-phase voltage source inverter (VSI) and controlled using vector control scheme. If current control is to be implemented in the rotating reference frame, a PWM method for the five-phase VSI is required to generate required voltages. This paper proposes a scheme to generate inverter output voltages using space vector PWM, in such a way that independent control of two five-phase series-connected machines is achieved with a minimum interaction between the two machines. The method generates output voltages that contain only two low-frequency fundamentals at operating frequencies required by the two machines. The concept is verified by simulation.