Djuptjärn and Högnäs 400 kV AIS substations

Sweden’s national electricity grid is a complex operation comprising about 15,000-km of power lines, 160 substations and switching stations and 16 oversea connections. To secure power supply to the northern city of Kalix, Linxon (former ABB) delivered two turnkey air-insulated switchgear (AIS) 400-kilovolt (kV) substations for Sweden’s national grid operator, Svenska Kraftnät.

The Djuptjärn and Högnäs substations comprise ten double-busbar, double-breaker bays (6+4) and 420 kV AIS equipment to enhance grid reliability and power transmission efficiency. The Högnäs substation is also important for the integration of clean wind energy into the national grid generated in the Västerbotten region.

For this project Linxon (former ABB) designed and supplied engineered packages for both high-voltage AIS substations, as well as key products and systems covering a range of advanced high-voltage equipment, such as the innovative combined Disconnector Circuit Breaker (DCB).

By integrating the disconnecting function into the circuit breaker, a DCB eliminates the need for two separate, free-standing disconnectors, and helps to shrink substation footprint by as much as 50 percent while increasing availability.

The Djuptjärn and Högnäs substations are also supplied with IEC 61850-based control/ protection systems and equipment. The turnkey EPC delivery of this project included design, civil, installation and commissioning works, and both installations were delivered on time fully meeting Svenska Kraftnät’s high quality standards. Despite a tight schedule and challenging work environment close to live overhead lines, there were no lost time incidents.

Linxon/ABB delivers turnkey electrical AC substation solutions for renewable and conventional power generation, power transmission and transportation, including project design, engineering, procurement, construction, management, commissioning and after-sales support.