Under an r18 million contract ABB is to supply two phase-shifting transformers to the Italian transmission company TERNA, a member of the Enel group. They are to be integrated into an existing station control system in an upgrading project designed to optimise the transmission of energy from France to Italy, which depends on electricity imports to cover its power requirements. The uneven utilisation of power lines in the European network system has so far meant that transmission capacity cannot be fully exploited. Using phase-shifting transformers increases the capacity of existing power lines, enabling major costs savings to be made.
ABB will be responsible for development and construction of the transformers and integrating them into the existing supply network. The company considers this an example of how transmission congestion can be alleviated by integrating advanced capability products into an existing system. Such a solution benefits the customer by providing increased flexibility and capacity for an important transmission corridor. Phase-shifting transformers are used to control energy flows in transmission networks and to balance out overloads and underloads. The two phase-shifting transformers are amongst the largest products of this type that ABB has ever supplied: they will each have a throughput capacity of 1630 MVA at a 400 kV rating. Each transformer weighs around 780 tonnes.