IMC-PI control-based solar PV output voltage regulation for battery charging

This study explores the application of an internal model control technique-based proportional integral controller to regulate the output voltage of a photovoltaic array for battery charging. The considered controller under investigation has not been previously examined for this specific plant. The inherent nonlinearity and dynamics of the system are addressed through the development and validation of an equivalent linearized model using small-signal modeling. The proposed controller is meticulously tuned to achieve maximum sensitivity by adjusting a single tuning parameter, and the methodology of controller design and tuning is thoroughly elucidated. The designed controller has been analyzed in detail using bode response. Comprehensive analyses, encompassing servo, regulatory, and robust assessments of the proposed controller, have been investigated across various uncertainties and disturbances in both simulated and real-world environments. The achieved performances demonstrate the efficient tracking of voltage essential for the charging system, even amid diverse uncertainties in converter parameters and environmental conditions. Moreover, the comparative responses observed in both Simulink and hardware environments serve to validate the efficacy of the designed controller. This validation is particularly evident when contrasted with an optimal proportional integral controller and a proportional integral derivative controller tuned using a metaheuristic gray wolf optimization technique, as well as against the proposed method and an advanced shifted internal model control method.