Three-phase and single-phase motor drive system with single three-phase two-level inverter for independent speed control.

This paper presents a dual-motor drive system with a three-phase two-level inverter for independent speed control of a three-phase motor and a single-phase motor. The single-phase motor is connected in series between the neutral point of the three-phase motor and the midpoint of two split DC-link capacitors. As the single-phase motor current is a zero-sequence component flowing in the three-phase motor, it does not affect the operation of the three-phase motor. The proposed drive system can reduce the number of power switches compared with the conventional drive system that uses a single-phase and a three-phase inverter. Thus, the proposed system can reduce the cost of the drive system. Simulations and experiments are presented to verify the proposed drive system. [ABSTRACT FROM AUTHOR]