Improved diode assisted voltage fed three phase quasi z-source inverter for photovoltaic application

摘要

In this paper, we propose a design and simulation of improved diode assisted voltage fed three phase quasi z-source inverter for photovoltaic application. Variable shoot through time interval is generated by adding low frequency voltage with constant voltage and the control signal for variable shoot is generated using boost PWM control. The output quality of three phase QZSI is improved by replacing the diode with active power switch in Switch Boost Inverter (SBI). Additionally, we use fuzzy logic controller for optimizing the shoot through duty ratio and modulation index from the source side rectifier, which increases the gain of three phase QZSI. The proposed topology in photovoltaic application increases the input voltage gain and voltage boost property by reducing the number of components, voltage ratings and stress across the switches in three phase QZSI. The proposed method enables improved voltage gain in single stage conversion, which is used for boost function. The simulation of proposed photovoltaic model is built on Simulink. Performance of proposed is evaluated against various metrics including power consumption, delay and power delay product and it is compared against existing VSI.