| Abstract:To address the strong source-load-storage coupling, stochastic renewable fluctuation, and limited scalability of centralized scheduling in distributed energy resource (DER) clusters, a multi-agent soft actor-critic (MASAC)-based intelligent scheduling and energy-efficiency optimization method is proposed. A dispatch model covering photovoltaic, wind, battery storage, controllable loads and a backup diesel generator is built, with a comprehensive energy-efficiency indicator in the objective and a linearized DistFlow model for voltage and branch constraints, plus daily SOC restoration and load energy-conservation constraints. The problem is cast as a partially observable Markov game under the centralized training with decentralized execution (CTDE) architecture; the contraction of the soft Bellman operator and the monotonic improvement of soft policy iteration are analyzed under ideal assumptions, the reparameterized policy gradient and temperature auto-tuning are derived, and the correspondence between the idealized theoretical properties and the engineering components of the deep implementation is established item by item, with each agent’s strictly local observations specified. Simulations on a modified IEEE 33-bus system compare the method with eight baselines: rule-based, MILP (perfect-forecast upper bound), MPC, MPC with perfect forecast (MPC-PF), IDQN, IDDPG, MAPPO and MADDPG, plus an ablation study. MASAC cuts total cost by 15.2%, 9.7%, 5.9%, 3.0% and 1.6% over rule-based, IDQN, IDDPG, MAPPO and MADDPG, within 3.5% of the MILP upper bound; the energy-efficiency indicator rises from 78.5% to 89.7%, renewable accommodation reaches 96.83%, and voltage deviation drops 22.5%. Under ±20% perturbations the cost standard deviation is 46.4% lower than MADDPG. |