September 6, 2021

MultiDC Webinar Series

23 Sep: Control of HVDC and Fast Frequency Reserves in Response to Decreasing Inertia

Date: 3:00-4:30 pm CET, Thursday, 23 September

Inger Segerqvist, Hitachi-ABB Power Grids

Benjamin Marshall, National HVDC Center [Slides]
Julia Matevosyan, ERCOT [Slides]
Robert Eriksson, Svenska Kraftnät [Slides]
Danilo Obradovic, KTH Royal Institute of Technology [Slides]


This webinar discusses and compares the current challenges within frequency control in power systems with additional support from HVDC interconnections and FFR units. These problems will be addressed relating to Great Britain, ERCOT, and Nordics systems that face similar inertia reduction trends. Even though similar in their approach, HVDC and FFR support are utilized differently depending on the respective systems’ nature and frequency control methodology applied.

27 Sep: Real-Time Simulation for Feasibility Studies in Converter-Dominated Systems

Date: 3:00-4:30 pm CET, Monday, 27 September

Ian Cowan, National HVDC Center

Laurids Dall, EnerginetDK [Slides]
Matas Dijokas, Technical University of Denmark [Slides]
Sebastien Dennetiere, RTE International [Slides]
-Robert Johansson, Hitachi-ABB Power Grids [Slides]


The increasing number of power electronic devices (PE) in any power system becomes a challenge to model power systems accurately and conveniently. This webinar discusses the role of Real-Time Simulations (RTS) in a project lifecycle and identifies simulation needs for system modeling with PE devices. Further, an implementation case of a low-inertia offshore grid with Hardware-in-the-Loop is presented highlighting the advantages of RTS and the ability to utilize it for planning and development studies.

30 Sep: The Role of HVDC in Energy Markets

Date: 3:00-4:30 pm CET, Thursday, 30 September

Spyros Chatzivasileiadis, Technical University of Denmark

Robert Eriksson, Svenska Kraftnät [Slides]                                                                      Thomas Krogh, EnerginetDK [Slides]
Andrea Tosatto, Technical University of Denmark [Slides]
Gonzalo Morollon, ENTSOe [Slides]


In the last decades, the transmission of power in the form of High-Voltage Direct-Current has proven to be a mature and reliable technology, such that more and more HVDC links are being commissioned around the world. Since their initial deployment, Transmission System Operators (TSOs) have used HVDC to improve system reliability and security, reducing significantly the operation costs of power systems. This webinar provides an overview of the gradual integration of HVDC in the European electricity market, starting from the experience gained by TSOs operating HVDC lines and continuing with the future changes in the European electricity market framework. Among the different aspects, the webinar will focus on market coupling, exchange of ancillary services via HVDC, and on the future role of HVDC in the electricity market.

04 Oct: Grid-forming Converters: The Road Towards High Renewable Energy Penetration and Energy Islands

Date: 3:00-4:30 pm CET, Monday, 04 October

Fitim Kryezi, EnerginetDK

Deepak Ramasubramanian, EPRI [Slides]
Xavier Guillaud, Ecole Centrale de Lille [Slides]
Georgios Misyris, Technical University of Denmark [Slides]


This webinar first discusses the role of grid-forming converters and their desirable characteristics for ensuring system stability in future low-inertia power systems. Then, it gives an overview of different control schemes of grid-forming converters. Finally, it analyzes the impact of grid-forming converters on the stability of a zero-inertia offshore system, in which multiple grid-forming converters operate in parallel.