Performance Analysis of Different Control Methods of Z-Source Inverter Feeding Industrial Drives

Abstract

This thesis highlights the comparative performance analysis of different control methods of Zsource inverter (ZSI) feeding industrial drives. It compares the fundamental output voltage, fundamental output current and their THD level of different control methods for ZSI. These results are then compared with conventional SPWM converter. The control methods of ZSI investigated in this work are simple boost control, maximum boost control and constant maximum boost control. The ZSI employs a unique impedance network that couples the converter main circuit to the dc source or load or another converter. The ZSI advantageously utilizes the shoot-through switching states in addition to active and zero states. The Z-source network makes the shoot-through states possible unlike traditional inverters and provides the unique buck-boost feature to the inverter. It overcome all the limitations and conceptual barriers of VSI and CSI and provides a new power conversion concept. Simulations of the circuit configuration and the control methods of the ZSI and conventional SPWM converter have been performed in MATLAB/SIMULINK.