Optimal power flow application to EHVAC interconnections for GW-sized Offshore Wind Farms

Operation of long EHVAC cable interconnectors requires controlling voltage/reactive power profiles. With reference to a hypothetical 200 km long 400 kV-50 Hz cable system, connecting to the grid three large OWFs with 2 GW total capacity, the paper compares results yielded by a dedicated algorithm with those of a standard OPF software. A parametric study of the interconnector was carried out, considering different dispatch scenarios and boundary conditions (network connection point voltages). Several cases were ran for an enlarged, meshed test system including the interconnector. Results show that solutions yielded by OPF and by the authors' algorithm are very close, confirming the effectiveness of the latter but also its possible replacement by a standard OPF when dealing with non-radial cable system topologies.