SwePol Link HVDC Cable Modernization Completed by Hitachi Energy

The 600 MW SwePol Link, a 254‑km high‑voltage direct‑current cable that runs under the Baltic Sea between the Stärnö substation in Sweden and Bruskowo Wielkie in Poland, underwent a full control‑system replacement in 2024. Hitachi Energy installed new MACH‑based control and protection equipment at both ends of the link, coordinating the work with the Swedish and Polish grid operators to avoid service interruptions.

Following the upgrade, the Swedish system operator Svenska kraftnät lowered the ramp‑rate limit for power transfers on the cable from 600 MW per hour to 300 MW per hour to align with new flow‑based transmission capacity calculations. A 250‑metre security zone was also established along the entire subsea route to protect the infrastructure from accidental or intentional damage.