To address the problem that the dispersion of the spatial location of each PVGUs within a centralized PV power plant leads to a strong spatial distribution of the internal voltage of the power plant and the problem that the voltage of the internal collector system crosses the line, a circuit model for the steady-state operation of the internal PV power plant is established, and a multi-objective reactive power optimization model is proposed to minimize the active power loss within the PV power plant and minimize the average deviation of the PVGUs. The multi-objective reactive power optimization model is proposed to minimize the active power loss inside the PV plant and the average voltage deviation of the unit ports, and the particle swarm algorithm is used to solve the model. Finally, a simulation case is used to verify the feasibility and correctness of the algorithm.