A PSO-Based MPPT Algorithm for Grid-Connected Photovoltaic Current Source Inverter

Maximum power point tracking (MPPT) controllers are a key element in photovoltaic (PV) energy conversion systems since they allow extracting the maximum power from PV generators. Metaheuristic algorithms such as the particle swarm optimization (PSO) are nowadays widely adopted and have shown their superiority to many other techniques. In this paper, a PSO-based MPPT algorithm is implemented to extract the maximum power from a grid connected current source inverter (CSI)-based PV system. CSIs are, inherently, single-stage boost-type topologies, which allow the injection of high quality sinusoidal AC currents with controllable power factor into the grid with a DC-link voltage level lower than the grid voltage amplitude. Accordingly, a space vector with pulse width modulation (SVPWM) technique is developed to, properly, control the CSI’s power switches and an appropriate proportional integral (PI) DC-link current controller is designed to ensure that the real power injected into the grid is always equal to the maximum power that can be extracted from the PV panel under all conditions. A numerical co-simulation of the overall PV system is realized using Matlab/Simulink and PLECS environments and the obtained results show the effectiveness of the proposed techniques for grid-connected PV applications.