Publication: Internal Power Balancing of an MMC-Based Large-Scale PV System Under Unbalanced Voltage Sags
Date
2024
Authors
Elsanabary A.
Mekhilef S.
Fadilah Ab Aziz N.
Journal Title
Journal ISSN
Volume Title
Publisher
Institute of Electrical and Electronics Engineers Inc.
Abstract
Modular multilevel converters (MMCs) are capturing the spotlight in large-scale photovoltaic (PV) applications. Studies reported their ability to work under different PV power unbalance conditions; however, no study has covered their operation under voltage sag conditions. This article proposes a multiobjective internal power balancing control to be applied to a competent PV-MMC configuration to simultaneously deal with both PV power unbalance and voltage sag conditions. The proposed strategy consists of two controllers: 1) a circulating current (CC) control which is responsible for balancing the power flow of the MMC under any PV power unbalance condition and 2) arm voltage compensation to deal with the unbalanced voltage sags and ensuring the CCs and submodule (SM) voltages are kept balanced without overmodulation issues. Also, the grid control is designed to keep a balanced current injection to the grid under any condition. The PV-MMC system and the proposed control are designed and tested using hardware-in-the-loop (HiL) and experimentally to validate the effectiveness of the control in eliminating any power unbalance under different operation conditions. ? 2013 IEEE.
Description
Keywords
Electric current control , Electric inverters , Electric load flow , Electric power system control , Power control , Quality control , Reactive power , Grid control , Inverter , Legged locomotion , Load flow , Modular multilevel converter , Modulars , Multilevel converter , Photovoltaic systems , Power balancing , Voltage sags , Power quality