Case Study
Boliden - Rönnskär

UMD secure operation of a 11kW lube oil pump during power outages and disturbances


Boliden’s plant Rönnskär in Skelleftehamn is one of the world’s most efficient copper smelters and are in addition Boliden’s greatest production unit. The plant receives deliveries of copper and lead concentrates from both Boliden’s own mines and from external suppliers. The smelter is a world leader in electronics recycling. Boliden extracts primarily copper, gold and silver from these materials.


Rönnskär are facing a great challenge as the producing process must not lead to overheating. A 5,4 MW blower is pushing the gas through the process which occurs during the production of sulphur products. If a power outage is occurring during operation the blower lube oil system needs to have a continuous operation to avoid overheating in the shaft bearings. Boliden decided to invest in a solution to secure the operation of the 11kW lube oil pump during power outages and disturbances.

The key requirement was the solution coverage:

  • It had to embrace every production activity.
  • The solution had to be bullet-proof, considering all possible situations that can emerge.



KraftPowercon proposal was a complete solution based on its system for uninterruptible motor drives (UMD™) for uninterruptible operation of a standard AC-motor with mains supply and with back-up from a battery system. The transition from mains supply to battery supply is automatic and seamless. UMD™ is built with integrated variable frequency drive (VFD). All components are from premium brands maximizing reliability and operational lifetime. System is designed for industrial environment and can be installed and serviced by the customers own electrical team decreasing both installation and lifetime costs.

Uninterruptible Motor Drives – UMD

The primary reason we chose UMD™ was that we got a tested and documented turnkey solution where all design was included. Installation went very smooth and UMD™ arrived pre-tested and could easily be installed during a short outage by our own staff. We got instant and correct response on the few questions we had during the installation.

Kevin Kågström - Supervisor Electrical Department, Boliden Rönnskär