A Physics‐Informed Offset‐Free MPC Approach for Islanded PV–Battery DC Microgrids without Explicit Disturbance Modelling

ABSTRACT

Reliable operation of standalone PV–battery DC microgrids is challenged by significant uncertainty in PV power generation, which degrades the performance of model predictive control (MPC) strategies—particularly with respect to DC bus voltage regulation and maximum power point tracking (MPPT). This paper presents a physics‐informed offset‐free MPC approach that explicitly compensates for PV production prediction errors. The method incorporates real‐time irradiance‐model updates based on the PV physical characteristics, enabling the controller to correct forecasting inaccuracies without requiring additional disturbance or offset states. Simulation results show that conventional MPC becomes highly sensitive to irradiance prediction errors, causing deviations from the maximum power point, reduced energy extraction and fluctuations in DC bus voltage. In contrast, the proposed controller maintains accurate MPPT operation, ensures stable DC‐link voltage regulation and respects battery state‐of‐charge limits even under large PV prediction uncertainties. Quantitatively, the method improves MPPT tracking accuracy and reduces DC‐link voltage deviation compared with standard MPC across a wide range of operating conditions. These findings demonstrate that the proposed physics‐informed offset‐free MPC significantly enhances the robustness and reliability of standalone PV–battery DC microgrids subject to uncertain solar conditions.