Report from the second Best Paths dissemination workshop

By late 2016 BEST PATHS had entered the advanced phase of technology development leading to its final goal: showing what several critical network technologies can do to raise the capacity of Europe’s transmission network and the flexibility of its electricity system. Experts in the energy field met in Berlin that October to discuss and validate the project’s mid-term progress and early results.

The five large-scale demonstrations were the technical core of the project. Spread across Europe, they aimed among other things to upgrade and repower existing DC and AC lines, improve HVDC connections to renewable generation sites and develop new superconducting DC links.

All five shared one overarching goal, to let European networks keep delivering high performance to grid users at affordable cost, but the work inside each was quite different and ran in parallel. That made BEST PATHS the largest demonstration project in the power grid field financed under the Seventh Framework Programme.

Results presented in Berlin

The consortium showed preliminary results of its research on the interactions between wind turbine converters and the HVDC substation. The laboratory set-up used scaled models, including a 4-terminal DC grid with 60 kW MMC VSC prototypes and a Real Time Digital Simulator emulating the AC grid.

Demonstration 2 was the first systematic study of interoperability problems in multi-vendor VSC-HVDC systems. It had already produced first recommendations for TSOs, vendors, universities and standardisation bodies on improving interoperability in multi-vendor HVDC-VSC schemes.

For Demonstration 3, led by Terna, work with Nexans had produced a prototype length of HVDC XLPE submarine cable intended for revamping the grid links of Sardinia, Corsica and mainland Italy. The cable passed a water penetration test at 100 bar, equivalent to a depth of 1,000 m, with water limited to 2.4 m from a point of damage.

The team was also working on moving energy efficiently over long distances. Building new AC corridors often lacks public acceptance, so the project chose to repower existing ones and to develop lighter towers for remote areas where traditional towers cannot be deployed. Demonstration 5 addressed transmission with a 10 kA MgB2 superconductor.

The panel

A lively panel discussion brought in members of other European projects in the same field, including e-Highway2050, MIGRATE, GARPUR and PROMOTioN, with a contribution from WindEurope. Cooperation between research areas was described as essential, above all in the power sector, where many stakeholders must back an innovation before it reaches European society.

The workshop proceedings, including an attendance list, were published in a summary report, and the slides are listed with the presentations from the second workshop.

The submarine cable tested for SACOI was meant for a 385 km line that dates from 1967; its successor, SACOI 3, is expected to enter service in 2029.