Real-time hardware-in-the-loop modelling and simulation of a grid connected solar energy system

Abstract

The growing concern for environmental conservation and the ever-increasing global energy demand have thrust renewable energy systems (RESs) into the spotlight. RESs offer a compelling solution by simultaneously reducing harmful emissions and harnessing an essentially boundless source of primary energy. Among RESs, photovoltaic (PV) systems have emerged as a popular choice for both residential and grid-connected renewable energy applications. This study is dedicated to achieving seamless power synchronization between two distinct energy sources such as Photovoltaics (PV) systems and the utility grid. To accomplish this objective, a novel maximum power point tracking (MPPT) algorithm is introduced. This algorithm is meticulously designed to efficiently regulate the switching element of a DC-DC boost converter. It excels at swiftly tracking the maximum power point while ensuring voltage stability, irrespective of fluctuations in solar radiation. The incorporation of precise speed control is pivotal in extracting maximum power from PV systems. Consequently, the proposed system offers an effective mechanism for achieving harmonious power synchronization. The central focus of this research revolves around the evaluation of system performance and control techniques for the seamless integration of PV systems into the utility grid. Successful integration hinges on the ability to align the frequencies and voltages of PV systems with those of the grid. To achieve this synchronization and enable the injection of alternating current into the grid, the study employs the phase-locked loop synchronization technique (PLL). This method is thoroughly elucidated, simulated using MATLAB/Simulink, and validated in Typhoon HIL 402 real-time simulator. Furthermore, the study addresses the performance evaluation and control engineering aspects of PV systems integrated into utility grids. This encompasses the synchronization of alternating current outputs of grid-powered systems through proportional-integral (PI) control methods. The research employs simulations and testing using software like MATLAB/Simulink and Typhoon HIL 402 real-time simulator to scrutinize and optimize synchronization control and the performance of PV systems in grid-connected applications. The findings of this research hold promise for countries with similar grid structures, such as South Africa, which can benefit from advancements in PV technology and grid-connected renewable energy systems.