Genetic algorithm-super-twisting technique for grid-connected PV system associate with filter

Abstract

This study proposes an intelligent robust controller to improve the performance of the multifunctional grid-connected photovoltaic (PV) system using the phase-locked loop (PLL). The novelty of this research is the use of a new strategy, called super-twisting algorithm (STA) based on genetic algorithm (GA) to improve the performance of the direct power control (DPC) with PLL technique and maximum power point tracking (MPPT), where DPC-STA-GA is used to control the active power filter. This proposed nonlinear technique is used to increase the power quality of the PV system under different conditions (variation of the nonlinear load, random nature of the irradiance solar and temperature,…etc). On the other hand, the STA-GA controller is successfully applied to control the DC link voltage of the multi-functional voltage source inverter. Durability and ease of implementation are among the most prominent features of the DPC-STA-GA with PLL technique to reduce the reactive and active power ripples compared to the DPC technique. The suggested intelligent nonlinear control ensures the harmonic current compensation and the transmission of PV energy to the electric grid and or the nonlinear load with high quality. To implement and verify the proposed controls with the PLL technique, Matlab software is used for this purpose, with the study of the behavior of the proposed controls based on STA-GA controllers with the PLL compared with the DPC in different conditions. The simulation results demonstrated the contribution of the DPC-STA-GA with the PLL in improving the performance, efficiency, effectiveness, and durability of the system under normal and abnormal conditions, where the proposed control reduced overshoot value in DC bus voltage by 100% compared to proportional-integral controller. In addition to reducing the value of THD of current compared to DPC and DPC-STA by 18.82% and 43.33%, respectively, in the case of solar radiation equal 1000 W/m2.