Arc furnace and Plasma Torch

Heavy-duty rectifier systems for DC Electric Arc Furnace (DC EAF) and chopper systems.

For plasma torches, through which metals such as ferrochrome, ferronickel, cobalt, platinum, and metal scraps are processed, refined and recovered.


In these applications, the DC current typically varies in the range of 2kA to 10kA for plasma torches, 10kA to 130kA for DC EAF.
Melting of metals through a controlled DC electric arc requires a special designed power supply that integrates high current converters (IGBT, diodes and thyristors), a fast-digital current controller and optimized DC reactors to stabilize the process.
Based on a hands-on experience, FRIEM developed the software control of the electrode position, which can be supplied on request to optimize the electrical operation of the furnace.

FRIEM’s equipment grants the highest level of robustness, reliability, efficiency and longest lifespan, both in indoor and outdoor installation.

FRIEM’s holds a unique experience and know-how in power electronics, which are essential to support Customers in defining the most effective layout and topology of the power supply aiming at optimizing initial investment’s cost and maximizing production:

  • High precision of the arc control thanks to FRIEM’s Digital Controller “DRP” that grants an easy configuration and a complete diagnostic of the load and of the machine itself;
  • reduced customer’s effort in project handling. FRIEM designs and supplies the complete power unit, including transformer-rectifier assembly, DC isolators, DC busbars up to the furnace, DC smoothing reactors and the control of the electrode position;
  • reduced maintenance and longer equipment lifespan thanks to the high protection degree of FRIEM’s rectifiers;
  • highest reliability thanks to N-1 redundancy of semiconductors;
  • optimized use of manpower during installation, commissioning, start-up and operation thanks to 100% factory-tested equipment and FRIEM’s typical modular design.



MOBILITY Knowledge into efficiency


Knowledge into efficiency

SERVICE A partner to our Customer


A partner to our Customer

ENERGY Working now for the future


Working now for the future