As per the terms of the contract, ABB will design, engineer, supply and commission two 320kv land-based HVDC Light converter stations, one rated at 1,200MW at Blackhillock in Moray and another rated at 800MW situated at Spittal in Caithness.
ABB will also supply submarine and underground cables covering a total transmission length of nearly 160km.
ABB power systems division head Claudio Facchin said: "We are pleased to support this major transmission project that will enable integration of a significant amount of renewable energy into the grid and supply clean, emission-free electricity to millions of people.
"ABB pioneered HVDC technology and continues to lead the way through innovation, as seen from several recent breakthroughs."
Expected to start operations in 2018, the transmission link will connect the electricity grid on either side of the Moray Firth in northern Scotland.
The Caithness-Moray link would provide enough energy for about 2,000,000 residents in Scotland.
SHE Transmission is bolstering the power network serving the north of Scotland. It aims to meet boost electricity generation from renewable sources, with about 1,200MW of wind, wave and tidal energy planned to be linked.
