Economic and technical criteria for designing future off-shore HVDC grids

In the scope of a recently launched European Research Project, a team of experts from public laboratories and TSO is in charge of defining the concepts and methodological approaches to design and analyse the technical and economic feasibility of future HVDC grids. This work aims at identifying, assessing and comparing several possible HVDC network topologies, with appropriate control and protection schemes, able to collect wind energy on large areas, transmit it at the best points to the AC grid and provide the necessary ancillary services for optimising the DC / AC interconnection in normal and disturbed conditions. The methodology adopted for the study and presented in this paper will focus on three main items: 1. identify and assess the economic drivers for the development of off-shore HVDC networks 2. identify the requirements for an optimal operation of the AC / DC interconnected power systems under normal and emergency conditions 3. conceptualise the coordinated control / command and protection plans for HVDC networks This paper gives a comprehensive view of the issues and tasks to be addressed during the run of the project.