In order to enhance the power quality of the distribution system while taking into account variations in solar irradiation and unbalanced grid circumstances, this research offers an optimum integrator control method for a three-phase single-stage grid linked solar array system. To obtain the greatest power from a solar array under various climatic circumstances, the P&O based maximum power point tracking (MPPT) approach is applied. The suggested control method further enhances load stabilisation, harmonic mitigation unit power factor operation, and reactive power mitigation. Under fluctuating solar irradiance, the optimum integrator control technique lowers voltage fluctuation in the DC link voltage and provides DC offset rejection in the Voltage Source Converter (VSC) input voltage. The primary objective of this suggested control strategy is to extract a positive sequence of per unit phase voltage values and to operate in weak grid and unbalanced grid voltage conditions. The MATLAB findings illustrate how the system responds to both steady-state and dynamic conditions, such as imbalanced loads and variations in solar irradiation. The THD of the source current and voltage as specified in IEEE 519 standards are attained, according to an analysis of the data.