Comprehensive Review on Multi Terminal DC Systems in Electrical Power Systems

The development of Multi-Terminal Direct Current (MTDC) systems has gained significant attention in modern power transmission networks due to their superior performance in integrating renewable energy sources, enhancing grid reliability, and improving overall power flow control. MTDC systems extend the conventional two-terminal HVDC systems into multi-terminal configurations, enabling power transfer among multiple locations through high-voltage DC lines. This configuration is especially beneficial in offshore wind integration, long-distance interconnections, and regional power exchange. The MTDC concept provides several advantages such as reduced transmission losses, flexible power control, and improved stability of interconnected grids. The recent advancements in converter technologies, including Voltage Source Converters (VSC) and Modular Multilevel Converters (MMC), have made MTDC systems more feasible and efficient. However, challenges remain in protection schemes, control coordination, and system scalability. This paper provides a comprehensive review of MTDC system architecture, control strategies, applications, and advantages, along with a comparative assessment against traditional AC and point-to-point HVDC systems. The study highlights MTDC’s role in the evolution of future smart grids and its potential for ensuring sustainable, reliable, and flexible power systems.