Another Q-One power feeder to Japan

JFE Bars and Shapes Corporation decided to install a new Q-One power supply system on an existing EAF manufactured in Japan, at Himeji Works, Hyogo prefecture, in the west part of Japan, where bars and shapes are produced from scrap.

Designed, developed, and patented by Danieli Automation, since 2016 Q-One is the first and only industrialized application of power electronics to control electric arc current and voltage in the EAF. Using the conventional furnace design, this solution can impose arc current, with the consequent benefits in process stability, drastically reducing the impact on the connecting electric network.

Q-One is the only system that makes frequency changes possible in arc furnaces. A frequency higher than network nominal improves arc stability and therefore is used during the boring stage, while a frequency below nominal –down to 20 Hz– is ideal for reducing energy consumption in the refining stage and for deeper penetration of the arc in the molten bath, as well as to induce a beneficial stirring effect on the molten steel.

Hybrid by design, Q-One powers EAF and LF furnaces also by making direct use of renewable energies, including an innovative function of power peak shaving, ensuring drastic reduction of power-on/power-off effects on the network.

The Q-One power feeder, which will be installed at Himeji Works by mid 2025, consists of seven units for an arc power of 72 MW; and is expected to improve energy and production efficiency by approx. 10%. Being a green investment, it will be subsidized by an energy conservation grant from the Japanese government.

JFE is the 45th Q-One power feeder for electric steelmaking/refining ordered from Danieli worldwide and fourth in Japan.