Abstract—This paper investigates the performance of a 4-switch, 3-phase Z-source inverter (4S3P) fed cost effective induction motor (IM) drive system. In the proposed approach, instead of a conventional 6-switch, 3-phase inverter (6S3P) a 4-switch, 3-phase Z-source inverter is utilized. This reduces the cost of the inverter, the switching losses, and the complexity of the control algorithms and interface circuits to generate 6 PWM logic signals. Furthermore, the proposed 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 new Z-source inverter system provides ride-through capability during voltage sags, reduces line harmonics, improves power factor and reliability, and extends output voltage range. Analysis, simulation, and experimental results will be presented to demonstrate these new features.

Index Terms—z-source inverter, voltage sags, four-switchthree-phase inverter, Harmonic distortion.

K. Srinivasan, is research scholar of Sathyabama University Chennai,Tamilnadu, India. Presently working in valliammai engineering college(e-mail : omsrivas@yahoo.co.in).
S. S.Dash, Professor in Electrical Engineering Department, S.R.M.University, Chennai-603203 Tamilnadu, India (e-mail:munu_dash_2k@yahoo.com).

Cite: K. Srinivasan and Dr.S.S. Dash, "Performance Analysis of a Reduced Switch Z-Source Inverter fed IM Drives," International Journal of Computer and Electrical Engineering vol. 2, no. 4, pp. 649-653, 2010.