Efficient and robust control of a standalone PV-storage system: An integrated single sensor-based nonlinear controller with TSCC-battery management

Abstract

The aim of this research undertaking is to investigate an integrated approach that extends the battery life of a single-stage off-grid photovoltaic system while simultaneously increasing the availability of solar photovoltaic power. This paper takes a synergistic approach to addressing these issues, in contrast to the numerous prior papers that have investigated them individually. In regard to the initial issue, this article proposes a hybrid MPPT solution which combines a backstepping controller with a distinct single-sensor MPPT approach. The aforementioned integrated system guarantees the exact attainment of the maximum power point (MPP) of the photovoltaic solar array, regardless of weather fluctuations. With regard to the second issue at hand, the effective management of charge for lead-acid batteries is accomplished by employing a three-stage charging controller (TSCC). The simulation results generated in MATLAB/Simulink indicate that MPPT tracking and battery charge control exhibit markedly improved performance across a range of weather conditions when the climatic conditions of El Jadida city, Morocco are taken into account. The hybrid method, as proposed, indisputable surpasses alternative MPPT approaches such as Inc-PI, FLC, PSO, RegP, and IMP-PO, with respect to convergence time (<3 milliseconds), variation (<0.19 watts), and tracking efficiency (over 99.86 %). Furthermore, the battery station is outfitted with secure and appropriate charging modes. In conclusion, the experimental validation of the proposed system against an actual experimental system in the laboratory verifies its hardware and practical viability.