Case Study

North Sea Wind Power Hub (NSWPH)

Client locations:

Services: HVDC + Facts
Services: Renewables
Client/Project Profile:

The North Sea Wind Power Hub (NSWPH) is a conceptual large-scale offshore island used to transmit wind power from the North Sea to the North West European energy system through multiple 2 GW VSC HVDC bipoles in a hub-and-spoke topology. This will be the world’s first multi-terminal offshore HVDC project of its size to date (2022). The project is being investigated by the NSWPH consortium, a partnership between TenneT Netherlands, TenneT Germany, Energinet and Gasunie.


TGS was asked to perform a dynamic stability assessment using EMT simulations in PSCAD for two hub topologies, including an investigation of active power control schemes, large and small disturbance analysis, and impedance-based stability analysis.


Several technical challenges were overcome throughout the study, including:

  • The design of a new control methodology to resolve small-signal instability of tightly coupled parallel grid-forming rectifiers.
  • Coordination of reactive power between parallel grid-forming converters for AC voltage control.
  • Investigating various strategies to keep offshore wind farms connected and ride through system faults, including the use of AC choppers.
  • Operation of offshore wind farms in grid-forming mode. 
  • Modelling and coordination of DC breakers in a multi-terminal HVDC system.



Our highly skilled engineers at TGS were successful in solving numerous challenges using novel control techniques; proper coordination of controllers, and recommendations for system stability strategies using their expertise in HVDC and renewable integration. 

Our engineers worked interactively with all parties involved through progress meetings and workshops to address the requirements of the stakeholders.

Published Reports: