HVDC-VSC Multivendor Interoperability

The goal of the demonstration is to outline the conditions to ensure maximum interoperability for HVDC-VSC converters connected to a DC system. This will be done for all parties involved (utilities, manufacturers, standardization bodies, testing laboratories, etc.) at different project stages (from specifications to converter testing and commissioning) and for a wide range of HVDC arrangements based on recent VSC technology (in particular: MMC or Modular Multi-level Converters).

Leading HVDC manufacturers (ABB, Alstom and Siemens), major European TSOs (Elia, REE and RTE) and renowned academics (Ecole Centrale Lille and University of Strathclyde) will join their efforts towards by offering their experience on HVDC-VSC converters, power systems operation and “out-of-the-box” vision.

The activities will include defining a set of DC system topologies for a wide range of situations (connection to strong / weak AC networks and to offshore wind farms; converters in close electric vicinity or connected to different AC networks). In addition to these network conditions, functional specifications describing the requirements and expected behaviour of AC/DC converters will be provided for various conditions: normal operation, during and after a fault, and during special sequences (start-up, connection, disconnection, and shutdown).
 

Then, manufacturers will adapt their VSC converter models and controllers to meet these specifications, and provide dedicated models to run simulations in electro-magnetic transient EMTP-RV software. These models will be tested in multi-vendor configurations according to the DC system topologies initially defined. Interoperability issues are likely to occur at this early stage, either at the interface between manufacturers, or between an external master control and the converters, or caused by inappropriate behaviour if the specifications appear to be not comprehensive enough for a multi-vendor project.
 

The outcome of these tests is twofold: a first set of recommendations will be issued based on the experience gained with the previously described offline simulations. In addition, detailed replica specifications, enriched by the EMTP-RV simulations experience, will be provided to manufacturers for the provision of converters control cubicles. These cubicles (or control replicas) will be the exact hardware implementations of the manufacturers’ current control system solutions, as implemented in a real HVDC project. As for the offline models, the cubicles will be tested on previously defined DC topologies.
 

Finally, updated recommendations for the ENTSO-E and standardization bodies will be issued based on the results observed during the real-time simulation phase with the exact control replicas.

Demonstration’s results will include recommendations for both specifications and hardware control implementation which would ensure maximum interoperability for multi-vendor solutions. The proposed guidelines will provide feedback to the Network Code drafting teams of ENTSO-E, and form a solid basis to make significant advances towards interoperability requirements for multi-vendor HVDC grids as currently targeted by standardization groups (CENELEC, IEC, etc.).

• Improved understanding of the behaviour and recommended controls of VSC-HVDC converters for future DC grids.
   
• Decisive step toward VSC converters standardization, thanks to the participation of three key manufacturers
   
• To knock down the last technical barriers for massive integration of renewable, including offshore wind power.

RTE (DEMO leader), ABB, Alstom Grid, Ecole Centrale Lille, Elia, REE, Siemens, University of Strathclyde