Great River Energy and ABB are soon to complete a major upgrade of the utility's high-voltage direct-current (HVDC) transmission system during a planned 74-day HVDC system outage, reports T&D World.

The system consists of a 436-mile transmission line and two converter stations, one at Coal Creek Station and one at Dickinson Station near Buffalo, Minnesota. The project includes refurbishment of the critical components of the system, along with the replacement of all major components in the converter stations on both ends of the transmission line.

The utility has been preparing for this upgrade since 2011. Its unique HVDC transmission system
delivers nearly all the power from Coal Creek Station, utility's largest power plant located Underwood, North Dakota, to Minnesota, where its 28 member-owner co-ops are located.

The project will merge today's HVDC technology with the existing system, aiming to ensure that Great River Energy and its member co-ops can deliver reliable power for the next 30 years.

Source: T&D World