Solar PV-Fed Multilevel Inverter With Series Compensator for Power Quality Improvement in Grid-Connected Systems

Abstract

Power quality difficulties arise as a result of Renewable Energy Sources (RES) integrating with the grid. Voltage swell, sag, and harmonic distortion occur on the grid due to power quality issues, which have an impact on customers. An inexpensive series compensator, like the Dynamic Voltage Restorer (DVR), is the best solution for overcoming the aforementioned problems. In this article, a solar PV integrated DVR with a novel multilevel inverter is introduced to address the power quality issues in the grid. The main objective of the proposed work is to develop a DVR integrated with a 23-level multilevel inverter to enhance the power quality. In addition, an improved INC-MPPT technique is designed for the boost converter for maximum energy extraction from the solar PV modules. Despite numerous benefits of multilevel inverters, there exist several reliability challenges such as fewer component counts and reduced THD. The suggested topology can able to generate 23 levels of output voltage with asymmetrical DC sources. The MLI has several advantages such as a reduction in the overall component count, cost and size of the inverter. Additionally, a detailed mathematical analysis is presented for the rotating dq reference frame control. The dynamic performance of the DVR is evaluated with a balanced load and implemented experimentally. Simulation results of the proposed system are carried out using MATLAB/Simulink. The proposed system is implemented using a dSPACE controller with a laboratory hardware prototype and OPAL-RT real-time simulator setup as well. The results show that the design of the proposed system is more effective at compensating for voltage sag and improves the power quality significantly. The THD obtained at the grid side is lower, which is under IEEE standards.