Modeling and simulation of SEPIC converter based solar simulator circuit for accurate testing and analysis under varying solar radiation conditions

As photovoltaic (PV) systems continue to grow in both industrial and residential applications, the need for accurate and reliable testing methodologies become increasingly important. Solar simulators are crucial tools for testing and analyzing the performance of PV systems under different conditions. In recent years, solar simulators have emerged as promising tools for understanding PV systems, offering advantages over traditional methods. This paper proposes the modeling of a single-ended primary inductance converter (SEPIC) based solar simulator that replicates the current-voltage (I–V) characteristics of an actual PV module. The circuit model was developed and tested under varying environmental conditions, including rapidly changing irradiance levels (600 W/m², 1000 W/m², 800 W/m²) at constant temperature (25 °C) with a modified Perturb and Observe (P&O) maximum power point tracker (MPPT) algorithm in Matlab/Simulink. Unlike the traditional P&O MPPT, the modified P&O simplifies the algorithm steps and the computing stage; therefore, it requires fewer lines of code to execute the tracking process. To demonstrate the effectiveness, the simulation results are compared to a real PV module, the Kyocera KC-60. According to the simulation results, the proposed SEPIC converter based solar simulator is an effective tool for developing and testing PV systems with 97.3% average power conversion efficiency, accurately replicating the module behavior under various conditions, enhancing reliability and efficiency.