Comparison Study of Z-Source and V-Source Feed 3-Phase Induction Motor

Abstract

This article presents the control of an induction motor with a Z-source inverter system. The Z-source inverter can effectively reduce the voltage stress across the capacitors in the impedance network. The Z-source inverter system employs a unique LC network in the dc link and a small capacitor on the ac side of the diode front-end. By controlling the shoot- through duty cycle, the Z-source can produce any desired output ac voltage, even greater than the line voltage. As a result, the Z-source inverter system provides ride-through capability during voltage sags, reduces line harmonics, improves power factor and reliability, extends output voltage range and also reduces the cost of the proposed topology, which is in turn used to control the speed of an induction motor. Old topologies like VSI produce stress over switching device. The simulation results indicate that the proposed topology is a promising technique that can be applied to improve overall efficiency.