Performance Evaluation of Current Control Techniques for Grid Connected PV System under Unbalanced Grid Faults

As the number of distributed generation power plants are being increasingly connected to the grid, the system operators are continuously revising the grid codes which enhance the reliability for a continuous supply of power. The power electronics interface plays a vital role in controlling the amount and quality of power components that are injected into the grid. Thus, a well-designed current control strategy is essential which governs the performance of the grid-connected PV (GCPV) system under normal or fault conditions. The selection of appropriate control strategies also helps in fulfilling various control objectives. This paper evaluates the performance of conventional current control techniques of GCPV systems, when subjected to sudden variation in irradiance under unbalanced grid faults. The MATLAB/Simulink results helped in comparing the peak current amplitude in faulty phase of these four conventional strategies. Finally, the THD of these control strategies are compared to determine their overall performance