Abstract <p>This article looks into the integration of a grid-connected photovoltaic (GCPV) system with a unified power quality conditioner (UPQC) to address power quality issues in distribution network without using the battery for energy storage. The grid-connected photovoltaic (GCPV) systems must be resilient in the face of the grid disturbances and load variations to ensure the grid stability. This research shows that a compensator may reduce the impact of utility voltage variations on a solar PV distribution system, hence increasing the system’s efficiency. The MPPT technology, based on incremental conductance (InC), optimises energy extraction from the PV array with varying solar irradiation. The findings show that the system is successful at maintaining power quality and ensures dependable operation during the grid-connected and voltage disturbance scenarios. To assess the efficacy of the modelled system, a 40 kW double-stage GCPV system in the MATLAB/Simulink 2019b is modeled and performed ride through tests under both sag and swell conditions. The proposed multilayer modified adaptive notch filter (ML-MANF) based controller integrated with the GCPV-UPQC system achieves a total harmonic distortion (THD) of less than 5% during steady-state operation, complying with IEEE 519 standards. A key objective of the design is the series transformer, optimized for operation under harmonics-polluted grid conditions to enhance harmonic mitigation. Furthermore, under voltage sag and swell events, the controller maintains voltage recovery within 5 cycles of the perturbation, meeting the voltage ride-through requirements specified by IEEE 1547. The UPQC, when used in conjunction with the PV system, provides both load power factor correction and the grid assistance, assuring compliance with the modern standards, during utility-side voltage abnormalities.</p> Graphical abstract <p></p>