PR controller design and stability analysis of single stage T-source inverter based solar PV system

Solar Photovoltaic (SPV)-based power generation systems are popular among various renewable energy sources due to their flexibility in capacity addition and low maintenance cost .The output power from an SPV plant is intermittent due to inconsistent atmospheric temperature and irradiance, which influences the reliability, stability and power quality of the utility grid. To be specific the intermittency of solar plant output imposes harmonics and resonance issues in the grid. These issues can be solved by using appropriate controllers in the inverter system. In this work, a DC link voltage control-based PI controller and a rotating reference frame technique-based PR controller are used on the input side and on the grid side of the inverter, respectively .The PR controller minimizes the voltage distortion caused due to the resonance in the LCL filter employed on the grid side of the inverter . It also aids in reducing the steady-state error of the system, thus minimizing the lower order harmonics. The proposed controllers i.e. PI and PR controllers, are simulated and analyzed using MATLAB Simulink and the simulation results are validated using a 1 kW solar PV prototype model.