Decentralized Grid-Forming Control Strategy for PV-Based DC Microgrids Using Finite Control Set Model Predictive Control

Driven by carbon neutrality and sustainable development policies, the adoption of photovoltaic (PV) sources has grown significantly in recent years. The integration of distributed PV generation into DC microgrids has proven to be an effective solution. However, as the penetration of the PV sources increases, there is a growing need for these sources to participate in DC bus voltage regulation. To address this issue, this paper proposes a decentralized control strategy for PV-based DC microgrids that enables cooperation among multiple sources in the microgrid without communication. The innovative FCS-MPC control strategy is proposed for grid-forming PV units, taking into account the characteristics of PV and eliminating the requirement for an external PI controller. This strategy facilitates cooperation with grid-forming battery energy storage (BES) units based on FCS-MPC, leading to improved stability, reliability, and economy of the microgrid. Furthermore, various operating conditions such as islanded operation, grid-connected operation, switching between grid-connected and islanded modes, and bus short circuits are fully considered in the proposed strategy. Hardware-in-the-loop experiments are conducted to compare the performance of the proposed strategy against the existing strategies. The results demonstrate the effectiveness of the proposed strategy.