Switzerland-based ABB has bagged $260m order from Bonneville Power Administration (BPA), a power marketing agency within the US Department of Energy.
Under the order, the power and automation technology group will upgrade the existing Celilo high-voltage direct current (HVDC) converter station in Oregon for the American utility.
The power station connects Pacific Northwest and southern California through an electricity link, which was commissioned over 40 years ago in 1970.
The Celilo converter station is located at the north end of the Pacific DC Intertie, which has a capacity of 3,100MW.
Pacific DC Intertie transmits electricity from the Pacific Northwest to about three million households in the greater Los Angeles area.
For the latest project, Alstom will upgrade key components including valves, controls, transformers, switchgear and cooling equipment.
The company will also modernize the converter station and make it feasible to boost capacity up to 3,800MW.
ABB Power Systems division head Brice Koch stated, "The converter station upgrade will enhance the reliability of this important HVDC link, thereby reducing the risk of blackouts and helping to secure power supply in the region."