Tech Talk: Designing the Danish energy islands #3 – Impact of temporary MMC blocking functionality on DC grid protection design

Within the next decade, energy islands and energy hubs are planned to be built in the Baltic Sea and the North Sea. These energy hubs are key to Denmarks ambition of reaching the national energy and climate targets. Furthermore, such infrastructure projects will bring Denmark to the center-stage of energy supply to the rest of Europe by contributing renewable energy to the region.

From a pure financial viewpoint, such huge infrastructure projects are the largest in Danish history with budget of over DKK 210 billion.

In order to get there, new solutions and strategies to ensure stable and cost-effective operations of the energy islands are needed. This is what the innovation project Offshore Energy Hubs focuses on. In this project, partners are striving to develop technical solutions addressing several aspects of the energy hubs, which will be conveyed via a series of webinars:

1. Solutions enhancing operational stability and thereby security of the energy supply
   (Watch/re-watch the webinar HERE)
2. Stable and resilient hub design
   (Watch/re-watch the webinar HERE)

This 3rd Tech Talk explores the impact of converter operation during DC faults on the design and sizing of protection systems, focusing on the converter temporary blocking functionality (TBF). By relaxing design constraints on the converters and allowing them to temporarily block, this talk investigates the implications on the sizing of DC Reactors (DCR) and the current breaking capability of DC Circuit Breakers (DCCB) with varying operating times (2ms, 5ms, and 8ms).

Speaker:
Domagoj Hart, Project manager and R&D engineer, SuperGrid Institute

Moderator:
Gitte Wad, Project Manager, Energy Cluster Denmark