Autonomous operation strategy of multiple dispatchable hub-stations connected with MMC-MVDC

This study presents a unified framework that synergistically integrates renewable energy sources with Do-Not-Exceed (DNE) limits by leveraging modular multilevel converter (MMC)-based medium-voltage direct current (MVDC) and DC-linked energy storage systems. To facilitate the practical enforcement of DNE constraints in advanced system architectures, we propose an autonomous energy and DC voltage control strategy that incorporates dynamic MMC energy management. The proposed approach enhances the dispatchability of variable renewable energy generators while eliminating the need for additional communication methods among hub-stations. Supporting both grid-following and grid-forming inverters, this approach incorporates autonomous MMC submodule energy control and multi-hub coordination. Simulation results demonstrate its effectiveness as a scalable solution for future renewable-dominated power systems. • A unified framework enables dispatchable use of VREs by integrating them with DNE limits via MMC-MVDC systems. • Autonomous energy and DC voltage control enables communication-free operation. • Multi-hub coordination strategy validated under high-renewable future scenarios. • Required ESS capacity quantified as hub-station numbers increase. • PSCAD simulations confirm scalability and adaptability of the proposed approach.