A Single-Phase Grid-tied PV based Trans-Z-Source Inverter Utilizing LCL filter and Grid Side Current Active Damping

Abstract

As grid-connected Photovoltaic (PV) based inverters are being used more, these systems play a more important role in the electricity generation by distributed power generators. Power injection to the grid needs to meet predefined standards. In this work, a PV based inverter consist of a Trans-Z-Source network performing as DC-DC power conversion level, is connected to the grid through a LCL filter. The connection through an LCL filter offers certain advantages, but it brings also the disadvantage of having a resonance frequency. A systematic mathematical design procedure for PR controller parameters along with active damping factor is presented and the overall control system leads to a considerably low value of grid current THD. Meanwhile the Maximum Power Point Tracking (MPPT) of the PV arrays is obtained by a modified INC method. Simulations in various conditions are carried out in MATLAB/Simulink environment and results depict suitable performance of the system with designed parameters.