Fuzzy Logic Decoupling Control of Real and Reactive Power in Grid-Connected Photovoltaic Power System based a Seven Levels Inverter Linked to a Three-Stage Boost Circuit

The paper presents a detailed modelling, simulation, and control of the real and reactive power flows in the Grid-Connected Photovoltaic Power system (GCPV) based on seven-phase voltage source inverter linked to a three-stage boost circuit interfacing a photovoltaic (PV) generation system to the power grid. Synchronisation of the inverter and grid AC waveforms is achieved using a phase-locked-loop (PLL) circuit. An effective decoupling strategy based on fuzzy logic controllers (DFLC) is designed to eliminate the interaction between the two current components. The DC-link voltage is controlled using a closed loop scheme based on a clamping bridge and an adaptive fuzzy logic PI controller (AFLC-PI). The overall model is implemented in Matlab and Simulink/SimPowerSystems toolboxes. Simulations results with the PV system operating with real irradiance data are presented to demonstrate the performance of the proposed decoupling and control strategies under different conditions of the power grid.