Coordinated Control of a Solar and Battery System in a Microgrid

This paper investigates the control strategies of a Li-Ion battery group with a PV array within a microgrid. In the grid-connected mode, the battery and the PV array operate at power control mode, while in the autonomous mode the battery provides voltage and frequency control instead. This paper presents a detailed model of battery including state of charge (SOC) modeling, analysis of short-time and long-time transient characteristics, and analysis of a detailed PV array model. This paper also presents effective control strategies for a battery with the PV array system to operate at both the grid-connected and the autonomous modes. The paper presents results from a test microgrid consisting of a voltage source converter (VSC) interfaced battery, a PV array, passive loads and an induction machine which is built using power systems simulation software. The paper presents results from simulations that demonstrate the proposed control strategies, which could assist in the coordination of independent distributed generation.