Hybrid HVAC/HVDC

Economic load flow analysis: Assess potential transmission capacity increase and congestion relief with Swisshybrid AC/DC lines.
Dynamic analysis: Analyse impact on dynamic stability via maximum fault clearing times of Swiss example system (Figure).

Figure: Swiss Generator near HVDC converter. Frequency for different fault clearing times. Instability for long fault durations. — Swiss Generator near HVDC converter. Frequency for different fault clearing times. Instability for long fault durations.

European transmission system reaches its capacity limits.
Conversion of existing HVAC overhead lines to hybrid HVAC/HVDC lines can accelerate required grid reinforcements in Switzerland (Figure).

fig-hybrid-acdc-2 — Swiss high-voltage network with different potential HVAC/HVDC locations.

Full year OPF simulation of different hybrid options shows transit capacity increase up to 1GW (Figure).
Hybrid lines causes no local dynamic instabilities. Admissible fault clearing times is the same or even higher as without HVDC.

fig-sccer-furies-dynamics-2 — Change in available transit power for different locations of the HVDC link.

The external pagepaper summarizing the project results

Partners: ETHZ (FEN), ETHZ (HVL), Swissgrid, Axpo
Duration: 07/2018 - 12/2020
Funding: SNF
Project Team: Dr. Alexander Fuchs, Dr. Turhan Demiray, Dr. Jared Garrison

external pageProject website