This paper presents a new application of a genetic-fuzzy control system which controls the input energy to a three phase electric arc furnace. Graphite electrodes are used to convert electrical energy into heat via ph...This paper presents a new application of a genetic-fuzzy control system which controls the input energy to a three phase electric arc furnace. Graphite electrodes are used to convert electrical energy into heat via phase electric arcs. Con-stant arc length is desirable as it implies steady energy transfer from the graphite electrodes to the metallic charge in the furnace bath. With the charge level constantly changing, the electrodes must be able to adjust for the arc length to remain constant. A fuzzy PI controller tuned with genetic algorithms has been developed to be responsible for the ver-tical adjustment of the electrode tip displacement according to specified set-points to ensure that the arc lengths remain as constant as possible. The simulation results show that the system performances are satisfactory using the proposed method.展开更多
Based on the analysis of three-dimensional power conductor for DC arcfurnace, the electric arc deflection model was set up and the control system of the arc directionwas configured. According to the bus bar distributi...Based on the analysis of three-dimensional power conductor for DC arcfurnace, the electric arc deflection model was set up and the control system of the arc directionwas configured. According to the bus bar distribution at the bottom electrodes cooled by water, thearc direction control principle and its configuration were described. The simulation results showthat the control system can restrain the electric arc deflection and control the arc direction.展开更多
The AC electric arc furnace(EAF)is becoming a core apparatus of the modern steel industry.Nevertheless,it used to be a major threat of power quality in the traditional power supply system.In this paper,a flexible powe...The AC electric arc furnace(EAF)is becoming a core apparatus of the modern steel industry.Nevertheless,it used to be a major threat of power quality in the traditional power supply system.In this paper,a flexible power supply system of the AC EAF is proposed,which is expected to completely alter its inherent cognition of impact load in the power grid.The basics of the power supply for EAF are first reviewed and the novel techniques to enhance the operation flexibility of EAF are introduced.The power circuit and the control structure are then presented,followed by the detailed strategies of various operations fully considering the features of EAF.A large disturbance stability criterion based on the mixed potential theory is also established for the practical application.Both electromagnetic transient simulations using PSCAD and benefit analyses verify the feasibility of the proposed system.展开更多
The electrode regulator system is a complex system with many variables, strong coupling and strong nonlinearity, while conventional control methods such as proportional integral derivative (PID) can not meet the requi...The electrode regulator system is a complex system with many variables, strong coupling and strong nonlinearity, while conventional control methods such as proportional integral derivative (PID) can not meet the requirements. A robust adaptive neural network controller (RANNC) for electrode regulator system was proposed. Artificial neural networks were established to learn the system dynamics. The nonlinear control law was derived directly based on an input-output approximating method via the Taylor expansion, which avoids complex control development and intensive computation. The stability of the closed-loop system was established by the Lyapunov method. The current fluctuation relative percentage is less than ±8% and heating rate is up to 6.32 °C/min when the proposed controller is used. The experiment results show that the proposed control scheme is better than inverse neural network controller (INNC) and PID controller (PIDC).展开更多
在大型电弧炉的补偿应用中,为了应对电网电压不对称的应用条件,提出一种35 k V直挂式角接链式STATCOM网侧电流闭环综合补偿控制策略。该策略将经典电纳平衡补偿和网侧电流闭环控制相结合,使得链式STATCOM装置可以在电网电压不对称条件...在大型电弧炉的补偿应用中,为了应对电网电压不对称的应用条件,提出一种35 k V直挂式角接链式STATCOM网侧电流闭环综合补偿控制策略。该策略将经典电纳平衡补偿和网侧电流闭环控制相结合,使得链式STATCOM装置可以在电网电压不对称条件下对电弧炉负载进行无功、谐波和负序的综合补偿。经35 k V/±40 MVA STATCOM装置实际运行,结果表明:STATCOM装置能够在保持快速的动态响应的同时,实现良好的稳态补偿效果,并能抵御电网电压不平衡造成的影响。展开更多
文摘This paper presents a new application of a genetic-fuzzy control system which controls the input energy to a three phase electric arc furnace. Graphite electrodes are used to convert electrical energy into heat via phase electric arcs. Con-stant arc length is desirable as it implies steady energy transfer from the graphite electrodes to the metallic charge in the furnace bath. With the charge level constantly changing, the electrodes must be able to adjust for the arc length to remain constant. A fuzzy PI controller tuned with genetic algorithms has been developed to be responsible for the ver-tical adjustment of the electrode tip displacement according to specified set-points to ensure that the arc lengths remain as constant as possible. The simulation results show that the system performances are satisfactory using the proposed method.
文摘Based on the analysis of three-dimensional power conductor for DC arcfurnace, the electric arc deflection model was set up and the control system of the arc directionwas configured. According to the bus bar distribution at the bottom electrodes cooled by water, thearc direction control principle and its configuration were described. The simulation results showthat the control system can restrain the electric arc deflection and control the arc direction.
基金supported in part by the National Natural Science Foundation of China (No.U1866601)。
文摘The AC electric arc furnace(EAF)is becoming a core apparatus of the modern steel industry.Nevertheless,it used to be a major threat of power quality in the traditional power supply system.In this paper,a flexible power supply system of the AC EAF is proposed,which is expected to completely alter its inherent cognition of impact load in the power grid.The basics of the power supply for EAF are first reviewed and the novel techniques to enhance the operation flexibility of EAF are introduced.The power circuit and the control structure are then presented,followed by the detailed strategies of various operations fully considering the features of EAF.A large disturbance stability criterion based on the mixed potential theory is also established for the practical application.Both electromagnetic transient simulations using PSCAD and benefit analyses verify the feasibility of the proposed system.
基金Project(N100604002) supported by the Fundamental Research Funds for Central Universities of ChinaProject(61074074) supported by the National Natural Science Foundation of China
文摘The electrode regulator system is a complex system with many variables, strong coupling and strong nonlinearity, while conventional control methods such as proportional integral derivative (PID) can not meet the requirements. A robust adaptive neural network controller (RANNC) for electrode regulator system was proposed. Artificial neural networks were established to learn the system dynamics. The nonlinear control law was derived directly based on an input-output approximating method via the Taylor expansion, which avoids complex control development and intensive computation. The stability of the closed-loop system was established by the Lyapunov method. The current fluctuation relative percentage is less than ±8% and heating rate is up to 6.32 °C/min when the proposed controller is used. The experiment results show that the proposed control scheme is better than inverse neural network controller (INNC) and PID controller (PIDC).
文摘在大型电弧炉的补偿应用中,为了应对电网电压不对称的应用条件,提出一种35 k V直挂式角接链式STATCOM网侧电流闭环综合补偿控制策略。该策略将经典电纳平衡补偿和网侧电流闭环控制相结合,使得链式STATCOM装置可以在电网电压不对称条件下对电弧炉负载进行无功、谐波和负序的综合补偿。经35 k V/±40 MVA STATCOM装置实际运行,结果表明:STATCOM装置能够在保持快速的动态响应的同时,实现良好的稳态补偿效果,并能抵御电网电压不平衡造成的影响。
