Modeling of The Dynamics of Charge Carriers of A Photocell under Non-Stationary Lighting Conditions in The Simulink Environment

In this article, the dynamics of charge carriers in photovoltaic cells under non-stationary lighting conditions was modeled. Basically, transient processes occurring under sinusoidal, pulsed and linear-sawtooth illumination modes were studied using a model created in the MATLAB/Simulink environment, taking into account the processes of photogeneration, diffusion and recombination in a semiconductor. During the modeling process, the system of differential equations was spatially discretized using the Central Differentiation scheme and time integration was performed using Runge-Kutta methods. The Signal Builder, MATLAB Function, Integrator and Scope blocks were used in the model. Under sinusoidal illumination conditions, the carrier concentration and sinusoidal oscillation of the photocurrent were recorded. Under pulsed illumination, rapid growth and relaxation decay characteristics were determined. Under linear-sawtooth illumination, a linear increase in the concentration and current was observed. These results are explained by diffusion and recombination processes and provide a basis for analyzing the real operating modes of the photovoltaic cell. The results play an important role in developing practical engineering solutions, creating strategies to improve the efficiency of the photovoltaic cell and protect it under different lighting conditions.