Terminal stations design for submarine HVAC links Capri-Italy and Malta-Sicily interconnections

Submarine interconnections allow for the connection of large islands to the onshore transmission grid and for the decommissioning of local power plants, which are often old, inefficient and polluting. High voltage alternating current (HVAC) cables are an interesting solution for smaller power ratings and distances up to 120 km, due to lower capital costs and absence of converting stations, if compared to HVDC links. However the design of terminal stations of HVAC interconnections must account for some specific issues, such as switching equipment performance limits, reactive power compensation and insulation coordination. The paper deals with two recent examples of HVAC submarine link, i.e. the Malta-Sicily and Capri-Italy interconnectors, focusing on terminal substation design and testing.