Consensus Control for Energy Storage Systems

In this paper, consensus integral control is applied for energy storage in microgrids to synchronize the state-of-charge (SoC) and power levels of batteries with limited information exchange. Both local information (SoC and power level) and neighbors' information (SoC and power level) will be fed into an integral control installed at every battery converter. The design is based on consensus control and takes into consideration of real-world battery coordination requirements, e.g., all batteries should work in the same charging or discharging mode. Compared with the consensus control in the existing literature for voltage consensus or battery SoC/power consensus, this paper offers a simple design. The major assumption of this paper is that each converter should possess an integral control. This assumption is valid since indeed integral controls exist if converters are equipped with secondary frequency control. The designed consensus control is validated by simulations on 14-bus microgrid and IEEE 57-bus power system. Simulation results demonstrate the effectiveness of the consensus integral control for variety modes of operation: 1) charging; 2) discharging; and 3) load variation.