Control of three-phase inverter grid-connected solar system

Abstract

Grid-connected solar photovoltaic (PV) systems are rapidly increasing each year due to a growing global interest in renewable energy and rising energy demand. This project focuses on designing and modeling a grid-connected PV system using space vector pulse width modulation (SVPWM). It also reviews key aspects and literature related to the components of a PV system, the inverter, and the grid connection. The photovoltaic model is employed to replicate the characteristics of a real PV array, while a Perturb and Observe method for maximum power point tracking (MPPT) is introduced to optimize the DC-DC boost converter’s performance. In this project, a three-phase two-level voltage source inverter (VSI) is employed, controlled using two approaches: a synchronous reference frame with a proportional-integral (PI) controller and a stationary reference frame with a proportional resonant (PR) controller with space vector pulse width modulation (SVPWM). The control strategy includes a phase-locked loop (PLL) to acquire important data about the grid voltage. To connect the inverter output to the grid, an LCL filter is used to reduce total harmonic distortion (THD) in both the output current and voltage. The system model is created using the MATLAB/SIMULINK environment.