Double carrier pulse width modulated Z-Source inverter fed induction motor drives

This paper presents a Z-Source inverter system and Double carrier control technique applied for Induction motor drive system. Z-Source Inverter system consists of a unique impedance structure of two capacitors and inductors connected in cross fashion, which cannot be observed in traditional inverter system. This special Z-Source network effectively utilizes shoot through state to boost the DC link voltage. Amount of boost in voltage depends on shoot through duty ratio and size of Z-Source elements. Because of this unique feature it can provide ride-through capability during voltage sags. Also it helps to minimize line harmonics, improves power factor and reduces motor rating. This paper uses double carrier PWM control which has additional benefits over conventional PWM control methods. A model of Z-Source Inverter based Induction Motor drive is built in MATLAB/SIMULINK to demonstrate these features.