An Effective Transformerless PUC7-Based Dynamic Voltage Restorer Using Model Predictive Control

This paper investigates the performance of a seven-level Packed U Cell (PUC7) inverter-based transformerless Dynamic Voltage Restorer (DVR) topology under short-time voltage variations (voltage sags and swells). Unlike existing multilevel inverter (MLI)-based DVR solutions, proposed structure requires only one DC source (suitable for PV-based systems), capacitor, six switching devices to generate output voltage. Moreover, studied is characterized by reduced cost size due elimination injection transformer. The PUC7 controlled using multi-objective (filtering current, compensating voltage, PUC capacitor controls) Model Predictive Control (MPC) strategy. Simulation implementation tests are carried out demonstrate high at steady-state during transient conditions, while keeping load unaffected disturbances in grid