<p>The output of photovoltaic (PV) systems is influenced by environmental factors, including sunlight intensity. This may cause voltage fluctuations in the power grid. Moreover, the integration of inverters in PV systems can introduce harmonic distortion into the grid. Therefore, it is essential to evaluate the power quality of distributed PV systems in a scientifically rigorous and methodical manner. To accomplish this, a power quality evaluation method combining subjective and objective measures is proposed based on the projection pursuit model and priority graph method. First, each power quality index is classified into eight levels according to national standards. Next, elitist and catastrophe strategies are incorporated into the particle swarm optimization (PSO) algorithm, and the improved PSO algorithm is used to solve the projection pursuit model to calculate the objective weights. Subsequently, a Gaussian weight function is introduced in the priority graph method to determine the subjective weights. The final weights are obtained by combining both objective and subjective weights. Finally, the grade intervals are calculated based on the boundary values. The power quality data from different grid scales and photovoltaic integration scenarios are evaluated, and comparisons are made using statistical metrics and other methods. The results demonstrate the superiority and generalization ability of the proposed method.</p>