Optimal energy storage management for microgrids with ON/OFF co-generator: A two-time-scale approach

In this paper, we study the energy storage management of microgrids with combined heat and power (CHP) co-generator and renewable energy. There are two kind of demands in the microgrid, power demand and heat demand. The power demand can be satisfied by the electricity from grid, CHP co-generator, renewable energy and battery; The heat demand is meet by the natural gas, CHP co-generator and the thermal tank. We aim to minimize the microgrid´s operating cost by designing an intelligent energy storage management strategy based on the random system inputs, e.g., demands and electricity price and the CHP co-generator´s on/off decision. We formulate the problem as a stochastic non-convex optimization programming, which is challenging to solve optimally. We apply the Lyapunov drift-plus-penalty method [1] to design an easy-to-implement energy management strategy with provable near-optimal performance and requires no statistical information of the power and heat demands. Moreover, extensive empirical evaluations using real-world traces are provided to study the effectiveness of the proposed algorithm in practice.