To improve the economic efficiency, operational stability, and renewable energy utilization and self-sufficiency under the full guaranteed acquisition policy, this paper focuses on a PV-storage-diesel DC microgrid system and proposes a novel coordinated control strategy. It introduces grid-connection guarantee parameters, priority decision parameters, and market transaction parameters, which are integrated with traditional energy control strategies to refine system operation modes, achieve optimal mode switching, and ensure stable system operation. At the same time, a comprehensive evaluation system and corresponding simulation models are established to analyze and verify the proposed optimization strategy. Simulation and comparison results show that, while ensuring stable system operation, the proposed coordination control strategy increases renewable energy self-sufficiency by 2%~8%, enhances self-consumption by 4%~57%, and improves the overall system operating profit by 4%~28%. Therefore, it can be concluded that the proposed strategy can effectively improve the overall system operational performance and has broad application prospects in the context of renewable energy consumption under a “full guarantee acquisition + market-oriented trading” mechanism.