Real-Time Energy Storage Management With Renewable Integration: Finite-Time Horizon Approach

Abstract

We consider the design of cost-effective management of energy storage with renewable integration for load supply. We take a finite time horizon approach and formulate the control optimization problem aimed at minimizing the system cost over a fixed time period. Recognizing the unpredictable and nonstationary stochastic nature of system dynamics, we assume unknown arbitrary dynamics of renewable generation, load, and electricity pricing in formulating our problem. Furthermore, we incorporate detailed battery operation cost into the system cost. Different from the infinite time horizon problems in existing works, the coupling of control decisions over time, due to finite battery capacity, is more challenging to manage. We develop a special technique to tackle the technical challenges in solving the problem. Through problem modification and transformation, we are able to apply Lyapunov optimization to design a real-time control algorithm that relies only on the current system dynamics. The proposed control solution has a closed-form expression and thus is simple to implement. Through analysis, the proposed algorithm is shown to have a bounded performance gap to the optimal noncausal $T$ -slot lookahead control policy. Simulation studies show the effectiveness of our proposed algorithm as compared with two alternative real-time and noncausal algorithms.