Lyapunov Compatibility-Based Adaptive Consensus Algorithm in PV-BESS Integrated Island DC Microgrids: A Dynamic State of Charge Balancing

This paper proposes a novel State-of-Charge (SoC)- based power allocation strategy for photovoltaic (PV)-based DC microgrids, leveraging an adaptive consensus algorithm to ensure SoC balance across Battery Energy Storage System (BESS) nodes. The primary control scheme employs inner-loop current droop control to mitigate disturbances arising from PV operation. The SoC-based power allocation strategy serves as a secondary control mechanism, designed to maintain a uniform SoC level across all BESS nodes via the adaptive consensus algorithm. This algorithm is compatible with a range of secondary control types, thereby mitigating battery degradation. Specifically, the stability and compatibility of the SoC-based power allocation strategy are rigorously proven by constructing a Lyapunov function. The proposed control strategy is simulated in MATLAB/SIMULINK and in an OPAL-RT-based real-time simulation environment to demonstrate its effectiveness, in which the proposed adaptive consensus algorithm can accommodate two different secondary control strategies.