Research On The Control Strategy Of Electric Arc Furnace Regulator At Starting Phase

The process of EAF steelmaking is a typical industrial control process of nonlinearity, time-variation and randomness. The control objective of input electric power, reduction of power consumption and shorting the duration of heating mainly is completed by electrode regulating system. The control effect of arc starting directly influences the energy efficiency of electric arc furnace. Good arc starting effect can not only save energy, reduce the impact to power grid, improve enterprise economic benefits, but also can reduce the pollution and noise, achieve the effect of economic environmental protection operation.The thesis is based on the EAF control system of steelmaking factory, considering the craft trait of EAF and proceeds from the physics mechanism of AC arc. The physical phenomenon of arc is studied and the related factors which influence the stability of arc starting are analyzed, based on consulting a great deal of documentation at home and abroad. The model of AC arc is worked out.Aiming at the decoupling control demand of electrode regulator system for EAF, three control strategies of electrodes are thoroughly analyzed. The constant impedance control is chosen as the electrode system control strategy in this paper.Because of the various control performance requirements of electrode regulation in the different metallurgical stages and the related factors which influence the stability of arc starting, the fuzzy controller is designed in this paper. The simulation research proving the fuzzy control can get the ideal control effect in the arc starting phase of electric arc furnace. At last, two methods are proposed to improve the actual problem.