Authors: Dr. T. Ma, S. Derrah, Dr. M. Sedighy, J. Janzen, N. Voermann
Conference of Metallurgists 2009, August 26, 2009
Abstract
High voltage shielded arc operation of smelting furnaces imparts significant power (MW) swings which cause generator turbine speed variations on smaller capacity power systems. Excessive turbine speed variations appear as power system frequency swings which can be harmful to the power generation equipment, motors, and other equipment on the system, and may not be acceptable to other customers on a utility grid. The Smart Predictive Line Controller (SPLC) is a proven technology for smoothing out arc MW fluctuations using a continuously variable thyristor controlled series reactor. The SPLC also increases the average furnace power and improves the energy efficiency of the power generation equipment.
There are currently three high power furnaces equipped with SPLC, where the SPLC equipment has been installed in the main substation on the load side of the smelting furnace circuit breaker. The SPLC compensates the furnace arc with predictive changes in the circuit reactance at a speed of up to 60 times a second. Alternate equipment configurations of thyristor valves, reactors, and switchgear are compared from the stand point of maintenance, installation costs, and long versus short arc performance. The new trend in modularization of SPLC equipment and the resulting reduction in furnace tie-in, start-up, and commissioning time are presented.
