Simulink Simulation of Single-Phase Photovoltaic Grid-Connected System Operating in Island Mode

This Simulink simulation focuses on the operation of a single-phase photovoltaic grid-connected system under islanding conditions. The simulation comprehensively investigates the operational behavior of the PV system and its grid interconnection characteristics. Key components modeled include photovoltaic cell characteristics using diode-based equations, inverter operation principles implementing PWM control techniques, and grid stability factors through voltage/frequency monitoring algorithms. During the simulation process, we monitor critical parameters such as real-time power output from the PV array using MPPT algorithms (Perturb and Observe method implemented), grid voltage fluctuations through RMS calculation blocks, and system harmonic distortion using FFT analysis tools. The simulation incorporates protective relaying logic for islanding detection based on frequency and voltage threshold comparisons. Performance analysis includes evaluation of system efficiency under varying irradiance conditions (implemented through controlled voltage sources), transient response during grid disconnection events, and stability assessment using phase-locked loop (PLL) synchronization techniques. The model implements anti-islanding protection mechanisms using active frequency drift method in the inverter control system. This simulation provides detailed insights into the operational principles and distinctive characteristics of single-phase PV grid-connected systems during islanded operation, with particular emphasis on control strategy implementation and protection system design using Simulink's power system toolbox components.