Electric vehicle (EV) charging stations integrating photovoltaic storage and charging can not only utilize renewable energy, but also reduce the impact of fluctuations in electricity demand on the power system. However, large-scale EV charging piles connected to the power grid can lead to power system pollution and produce more serious power quality problems. In order to improve the stability and reliability of the power grid, this paper proposes a composite control method for power quality of optical storage and charging system based on shunt reactive power compensator. First, the parallel reactive power compensator structure is proposed, and the corresponding control mode switching is carried out through the transformer parallel composite device. Secondly, the design of power quality composite control strategy is proposed, including phase fast tracking module design and harmonic current detection module design. Finally, a simulation model is built in MATLAB/Simulink to verify the feasibility of the proposed control method.