| PhD Seminar

Name of the Speaker: Ms. Nimitha Muraleedharan (EE22D024)
Guide: Dr. Mahesh Kumar
Venue: ESB-244 (Seminar Hall)
Online meeting link: https://meet.google.com/afa-wczi-now
Date/Time: 8th April 2025 (Tuesday), 4:15 PM
Title: LVRT Operation with Power Management Strategy for Dual Voltage Source Inverter in Grid-Interfaced Systems.

Abstract :

With the increasing integration of renewable energy sources (RESs), maintaining grid power quality and stability while maximizing energy extraction remains a challenge in microgrids. To ensure stability during voltage disturbances, low voltage ride-through (LVRT) capability is mandated for RES-fed inverters, enabling them to stay connected to the grid by supplying appropriate active and reactive power. Implementing a suitable microgrid topology with an effective control scheme is thus essential for achieving multifunctional capabilities that enhance operational flexibility and reliability.

This work explores the dual voltage source inverter (DVSI) topology to enhance LVRT performance under voltage sag conditions. An LVRT strategy is implemented in the DVSI system to regulate the point of common coupling (PCC) voltage while simultaneously reducing voltage unbalance and power oscillations at the PCC through dual-sequence current injection. A power management algorithm is proposed to maintain power balance at the PCC and ensure maximum real power support during input and output disturbances. Additionally, a modified dual second-order generalized integrator-based quasi type 1 phase-locked loop (DSOGI-QTI-PLL) is introduced to achieve stable inverter operation under grid disturbances such as harmonic distortion, unbalance, and DC offset. The proposed control strategy of the DVSI system is validated by performing simulation and experimental studies on the developed hardware prototype.