News & Press Releases

VarioVerter cycloconverter controller for SIJ Acroni in Jesenice, Slovenia

London, May 25, 2021

Primetals Technologies to modernize cycloconverter drive of plate mill at SIJ Acroni in Slovenia

  • Replacement of obsolete cycloconverter drives will ensure availability of plate mill
  • Cost-optimized solution with new VarioVerter cycloconverter control and continued use of existing power units
  • Optional retrofitting capability of cycloconverter drive control enables plate mill to be operated with DC motor in the event of an emergency


SIJ Acroni d.o.o. has engaged Primetals Technologies to replace the existing cycloconverter drive control for the upper and lower motors on the plate mill's roughing stand at the Jesenice production site in Slovenia. The goal of the project is to maintain availability and secure the supply of spare parts. This will be done by replacing the obsolete drive and field control systems with the VarioVerter cycloconverter developed by Primetals Technologies and new field control systems. Installation work will not add any extra days to the annual winter shutdown and is due for completion in January 2022.


Installing the new VarioVerter also takes account of a request from the customer: should a synchronous motor be damaged, the customer would later like to have the opportunity of temporarily running the plate mill with a DC motor using the supplied drive control components.  


Primetals Technologies' scope of performance includes supplying two VarioVerter cycloconverter controllers, replacing the field control units, electrical assembly, and integration into the plate mill's existing basic automation control system, thereby largely leaving the interface situation unchanged.


SIJ Acroni is Europe's leading producer of stainless quarto plates. The company also specializes in electric and custom steels, which are sold as hot and cold-rolled coils, heavy plates and cold-formed sections, mainly for use in special niche products. The SIJ Acroni plant is located in Jesenice, about 60 kilometers northwest of Ljubljana, the capital city.

VarioVerter cycloconverter controller for SIJ Acroni in Jesenice, Slovenia

VarioVerter cycloconverter controller from Primetals Technologies. Two systems will be installed at SIJ Acroni in Jesenice, Slovenia.

Primetals Technologies, Limited, headquartered in London, United Kingdom, is a pioneer and world leader in the fields of engineering, plant building, and the provision of lifecycle services for the metals industry. The company offers a complete technology, product, and services portfolio that includes integrated electrics and automation, digitalization, and environmental solutions. This covers every step of the iron and steel production chain—from the raw materials to the finished product—and includes the latest rolling solutions for the nonferrous metals sector. Primetals Technologies is a joint venture of Mitsubishi Heavy Industries and partners, with around 7,000 employees worldwide. To learn more about Primetals Technologies, visit the company website