On Multi-modal Control Strategy In Electrode Regulator Of AC Electric Arc Furnace Studys And Applications

The AC electric arc furnace (EAF) is one of the key energy-consumingequipments in the metallurgical industry, the power consumption of the EAFaccounts for more than half of the total power consumption in the steelworks.China is a country lacking of power, many steelworks lost the competitiveadvantage in the market because of the overproportion of electricity charges inthe cost of the products. The electrode regulator is the core of the EAF’s controlsystem. It controls the arc length by manipulating the electrode height, so that itcan adjust the input power. The performance of the electrode regulator directlyaffects the steel production and quality and the power consumption. The study ofthe EAF’s electrode control system has both economic and safe significance.Through the research on EAF’s characteristics of the control object andsmelting process mechanism, this paper summarized its influence on electrodecontroller’s performance, explained the reason why an electrode controller withsingle strategy can not meet the control system’s requirements. This paperproposed a multi-modal control strategy, which possesses their respective meritsof the constant impedance, fuzzy and PID control method. The system canautomatically identify the current state, choose the best control strategy. Thepaper given the division method of the multi-modal control strategy, the controlalgorithms and how to achieve them. Through system simulation and field test,the results clearly verified its validity, and furthermore provided a basis andmodel reference for the optimal design of EAF’s electrode regulator.