Economic-Driven Frequency Regulation in Multi-Terminal HVDC Systems: A Cooperative Distributed Approach

In this paper, a distributed economic model predictive control (EMPC) method is proposed for economic operation and frequency regulation in isolated AC subsystems interconnected through multi-terminal HVDC (MTDC) transmission system. Economic-driven frequency regulation, including economic operation and frequency regulation, normally implemented in a separate and hierarchical way, can be integrated through the proposed EMPC. Instead of purely competing with neighboring subsystems, the proposed distributed EMPC encourages cooperation among the interconnected subsystems, improving system-wide control performance. A suitable Lyapunov function is utilized to prove the stability of the proposed method. Simulations are used to demonstrate the performance of the proposed EMPC method.