Contribution of synergetic control to the minimization of harmonics currents injected for grid connected photovoltaic systems

This paper presents a new synergetic control scheme for grid-connected photovoltaic (PV) systems. The proposed control scheme improves the quality of energy injected by the PV inverter into the grid by minimizing the total harmonic distortion (THD) of currents during low sunlight conditions. The proposed technique makes use of an intermediate virtual control to design the new synergetic control law which is applied on a grid-connected PV system supplying linear and non-linear loads. The effectiveness of the control scheme is simulated in Matlab/Simulink software. A comparison of simulation results with other linear and nonlinear control techniques in the literature show the effectiveness, superiority and satisfactory performance of the proposed scheme in minimizing the harmonics and THD of the currents under low solar irradiance. The results also show that the proposed synergetic controller is robust and has better dynamic performance under varying irradiance conditions.