A new technology for the control of AC electric arc furnaces

Design, installation and operating results of a Smart Predictive Line Controller (SPLC) for reducing are furnace nicker problem at Co-Steel LASCO in Whitby is presented. The installed SPLC is comprised of a 3f, 46kV thyristor-based AC switch rated at 100MVA, a real time central controller for on line control of the AC switch and a state of the art data acquisition system for the control/monitoring the performance of the are furnace system. Real time adaption to changes in furnace conditions, allows the SPLC to predict the correct parameters of the are furnace system and utilize a pre-calculated look-up table for adjusting the delay angles of the AC switch to reduce flicker. The installation and operating results of the SPLC at LASCO along with the limitations of the design and requirements are discussed in detail.