MATLAB-Based Photovoltaic Power Generation System with PV Model (Including MPPT Algorithm) and Grid-Connected Circuit

Photovoltaic power generation systems play a crucial role in modern renewable energy applications, and MATLAB provides powerful simulation tools for modeling and analyzing the performance of such systems. This article introduces how to build photovoltaic generation models in MATLAB, including photovoltaic panel characteristics and Maximum Power Point Tracking (MPPT) algorithms, and discusses design approaches for grid-connected inverters.

### PV Model The photovoltaic model serves as the core component for simulating the output characteristics of PV cells or arrays. In MATLAB, equivalent circuit models (such as the single-diode model) are typically used to describe the voltage-current relationship of photovoltaic cells. This model must account for environmental factors like irradiance intensity and temperature that affect output power. By adjusting irradiance and temperature parameters, users can simulate photovoltaic generation efficiency under different conditions. The implementation typically involves creating custom functions or using Simscape Electrical blocks to represent the nonlinear I-V characteristics.

### MPPT Algorithm Since photovoltaic power output is significantly influenced by environmental conditions, MPPT algorithms ensure the PV system always operates at the Maximum Power Point (MPP). Common MPPT algorithms include: Perturb and Observe (P&O): Determines MPP by periodically adjusting voltage and observing power changes. Incremental Conductance (INC): Quickly tracks MPP based on the slope of the PV curve, offering better dynamic response. In MATLAB/Simulink, users can build MPPT control modules using logic blocks and Stateflow, then validate tracking performance under varying irradiance conditions through simulation. The implementation typically involves measuring voltage and current, calculating power, and using comparison logic to adjust the operating point.

### Grid-Connected Inverter Design The ultimate goal of photovoltaic systems is to convert DC power to AC power and feed it into the grid. The control strategy for grid-connected inverters is critical and typically includes: Dual-loop voltage and current control: Ensures output voltage synchronization with the grid while maintaining injected current waveform quality. Phase-Locked Loop (PLL) technology: Detects grid voltage phase to guarantee proper phase matching of grid-connected current. In MATLAB/Simulink, engineers can construct inverter circuits using power electronics modules from Simscape Electrical and combine them with control algorithms for simulation analysis, validating system stability and efficiency. The implementation often involves PWM generation, Clarke/Park transformations, and PI controllers for precise grid synchronization.

### Simulation and Optimization Using MATLAB's simulation environment, engineers can comprehensively evaluate photovoltaic system performance, including MPPT algorithm tracking speed and grid-connected current harmonic distortion. By adjusting control parameters or optimizing algorithms, system dynamic response and energy conversion efficiency can be further improved. MATLAB's optimization toolbox and parameter sweeping capabilities allow for systematic performance analysis across different operating conditions.

MATLAB simulation of photovoltaic power generation not only helps understand system working principles but also provides valuable design references for practical engineering applications. The simulation framework enables rapid prototyping and validation before physical implementation.