A direct torque control for three-leg voltage source inverter fed asymmetrical single-phase induction motor

This paper presents the implementation of 5-leg voltage source inverter fed independently two single-phase induction motors with different speed. Space vector pulse width modulation is used for the five-leg VSI Closed-loop speed V/f scalar control is employed for those motors. The experimental results show that the speed for each motor can be independently control. Besides that, the advantages of the 5-leg inverter can be shared the capacitor and dc bus together, reduced the cost by decreasing the numbers of power switch and driver circuits and also reduced the switching loss.