Simulation of Solar Cell Powered Z-Source Inverter System

The aim of this work is to model and simulate embedded EZ-source inverter system. Traditional Z-source inverter (ZSI) and embedded EZ-source inverter (E-ZSI) are compared with respect to harmonic performances in solar system application. Z-source inverter has unique feature that can boost without DC-DC converter. It gains voltage tuning flexibility by introducing unique LC impedance network between input source and inverter circuitry. It also protects the inverter phases from short circuit damages with no dead time delay inserted. Being different from the traditional Z-source inverter a new family of embedded EZ-source inverter presented have their DC sources embedded within their impedance network so as to achieve implicit source current or voltage filtering without any additional LC filter thereby reducing the overall system cost and design complication. The operation principles of two inverter system is introduced first and based on the principles, voltage gain in both topologies are derived and compared. The analysis and comparison result shows that the embedded EZ-source inverter not only has same gain as Z-source inverter but also improved harmonic performance compared to conventional Z-source inverter. The simulation is done with RLE loads and the results are presented.