A HTF-Based Higher-Order Adaptive Control of Single-Stage Grid-Interfaced PV System

In this paper, a hyperbolic tangent function (HTF) based higher order adaptive control algorithm is used with perturb & observe based maximum power point tracking algorithm for a three-phase, single-stage, grid-interfaced solar photovoltaic system with distribution static compensator capabilities. The variable learning based HTF control algorithm is used for the reduction of the mean square error and increases the tracking speed in the system, thereby improving the response of the system. The HTF-based control algorithm is simple in implementation with easy mathematical formulations. The proposed system is simulated in MATLAB/Simulink and is tested on a developed prototype in the laboratory under various abnormal conditions, such as variable solar irradiation, load unbalancing, and voltage sag/swell. The response of system is satisfactory and the total harmonic distortions of grid current are within the limit, as outlined in the IEEE-519 standard.