Modular design

Electrical engineering

Topology (electrical circuits)

Computer network

Mathematics

Biology

Inverter

Operating system

Engineering

Voltage

Grid

Network topology

Electronic engineering

Geometry

Converters

Modularity (biology)

Computer science

Photovoltaic system

Galvanic isolation

Maximum power point tracking

Genetics

Transformer

IEEE Access

Medium-voltage (MV) multilevel converters are considered a promising solution for large scale photovoltaic (PV) systems to meet the rapid energy demand. This article focuses on reviewing the different structures and the technical challenges of modular multilevel topologies and their submodule circuit design for PV applications. The unique structure of the converter's submodule provides modularity, independent control of maximum power point tracking (MPPT), galvanic isolation, etc. Different submodule circuits and MPPT methods to efficiently extract the PV power are reviewed. The integration of the multilevel converters to PV systems suffers unbalanced power generation during partial PV shading conditions. Several balancing strategies to solve this problem are presented and compared to give a better understanding of the balancing ranges and capabilities of each strategy. In addition, the paper discusses recent research advancements, and possible future directions of MV converters-based large-scale PV systems for grid integration.

Medium Voltage Large-Scale Grid-Connected Photovoltaic Systems Using Cascaded H-Bridge and Modular Multilevel Converters: A Review