A Coordinated Control Strategy for Hybrid Multiterminal DC System for Effective Energy Sharing Between AC Grids

Hybrid Multi-terminal DC (H-MTDC) system with a combination of Line Commutated Converters (LCCs) and Voltage Source Converters (VSCs) will be one of the preferable solutions to solve challenges of interconnecting massive amount of renewable power generation in future power grid. Combining LCC and VSC topologies eliminates most of the limitations of these two HVDC technologies. However, a systematic control coordination strategy is required to operate such an H-MTDC grid. To that end, this paper proposes a new coordinated control scheme for a H-MTDC meshed network for exchanging power between multiple asynchronous AC areas. The effectiveness of the proposed approach following a single point failure (i.e. converter outage) is demonstrated using time-domain simulation in a five-terminal H-MTDC test system model developed in EMTDC/PSCAD.