Presentations

Abstract

To enable coordinated connection of offshore wind developments and enhance interconnection between price zones in the North Sea, the deployment of a multi-terminal DC (MTDC) system is being considered. Dual purpose MTDC systems facilitate complex interconnections between multiple generation sources and loads, and are particularly effective when generation sites are remote from consumption centres, as is the case for offshore wind parks. Understanding the potential operation of such systems is critical for effective planning and optimisation of their deployment. A transmission expansion planning (TEP) problem is formulated to support the design of the MTDC system. The objective is to identify new transmission corridors that minimise investment costs while ensuring operational efficiency. For the North Sea MTDC, these corridors consist of high-voltage direct current (HVDC) lines and the converters required to integrate them with the European alternating current (AC) grid. The operation of the MTDC system is optimised by considering power flows in both AC and DC networks. This optimisation solves for curtailment levels for renewable energy sources and the power set-points for converters and generators [1]. Cross-border imports and exports are determined based on zonal price differences until market equilibrium is reached, influencing local generation costs [2]. The TEP model evaluates the impact of modifying existing infrastructure or introducing new links, weighing these changes against their potential benefits [3]. The North Sea MTDC initiative aims to interconnect the price zones of Great Britain, Belgium, the Netherlands, Germany, Denmark, and Norway. A study by a committee of transmission system operators (TSOs) outlines the proposed hybrid interconnectors [4], which serve as the case study for this implementation.