An Overview of VSC-HVDC Systems and Challenges to Harvest Wind Energy Potential Considering South Asian Region as a Case Study

The voltage source converter-based high voltage direct current transmission (VSC-HVDC) is considered the most appropriate option to harness the maximum potential of renewable energy, particularly offshore wind. With improved reliability and functionality of the network, reduced conversion losses, and reduced cost, the VSC-based multiterminal direct current (MTDC) transmission has gained significant importance and popularity. This review paper provides a wide-ranging overview of VSC-HVDC networks. It includes detailed discussions on circuit configurations for VSC-HVDC, MTDC-based configurations for VSC-HVDC, and the converter topologies. The review also contains a discussion on the control methodologies for VSC-HVDC networks. Furthermore, it outlines the details of protection equipment, primarily focusing on conventional and advanced circuit breakers. In addition to the details of VSC-HVDC networks, this review also thoroughly examines the renewable energy landscape in the key South Asian Region (SAR). It provides pertinent renewable energy statistics to demonstrate the gap between the current utilization of renewable energy resources (RESs) and the potential of the region, with a preliminary focus on wind energy. Considering the major challenge of bridging the gap between the existing and available wind energy capacity, this review proposes some recommendations for maximizing the utility of wind energy by bolstering the VSC-HVDC transmission. By accepting the suggested premises, affordable access to clean energy can be made possible, contributing to the achievement of the United Nations (UN) Sustainable Development Goal (SDG) on affordable energy for the SAR to some extent. A comprehensive literature survey with key energy statistics concludes that an efficient and cost-effective transmission network is necessary to maximize the utility of available sustainable and renewable energy sources.