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
Non-equilibrium molecular dynamics（MD） simulations were performed according to the electronic anti-fouling technology, and some structural parameters and dynamic parameters of CaCl2 aqueous solution were taken as in...Non-equilibrium molecular dynamics（MD） simulations were performed according to the electronic anti-fouling technology, and some structural parameters and dynamic parameters of CaCl2 aqueous solution were taken as indicators to compare the different effect on the anti-fouling performance by applying different electric fields. The results show that electric fields can effectively decrease the viscosity of CaCl2 aqueous solution and enhance the ionic activity by enlarging the self-diffusion coefficient. In addition, with the same electric field strength, the electrostatic field is more effective at decreasing the viscosity of CaCI2 aqueous solution and increasing the self-diffusion coefficient of water molecules, while the alternating electric field is more effective at increasing the self-diffusion coefficient of Ca2＋. Furthermore, an alternating electric field with different frequencies was applied; the results show that an 800 kHz frequency is most effective to decrease the viscosity, and a 700 kHz frequency is most effective to en- hance the self-diffusion coefficient of water molecule. Otherwise, 400 kHz is most effective to enhance the self-diffusion coefficient of Ca2＋. Additionally, by studying the change of structure parameters, it was concluded that an external electric field can enhance the hydration between Ca2＋ and coordinated water molecules, and the alternating electric field is more effective in this respect.展开更多
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Supported by the National Natural Science Foundation of China（No.51408525）.
文摘Non-equilibrium molecular dynamics（MD） simulations were performed according to the electronic anti-fouling technology, and some structural parameters and dynamic parameters of CaCl2 aqueous solution were taken as indicators to compare the different effect on the anti-fouling performance by applying different electric fields. The results show that electric fields can effectively decrease the viscosity of CaCl2 aqueous solution and enhance the ionic activity by enlarging the self-diffusion coefficient. In addition, with the same electric field strength, the electrostatic field is more effective at decreasing the viscosity of CaCI2 aqueous solution and increasing the self-diffusion coefficient of water molecules, while the alternating electric field is more effective at increasing the self-diffusion coefficient of Ca2＋. Furthermore, an alternating electric field with different frequencies was applied; the results show that an 800 kHz frequency is most effective to decrease the viscosity, and a 700 kHz frequency is most effective to en- hance the self-diffusion coefficient of water molecule. Otherwise, 400 kHz is most effective to enhance the self-diffusion coefficient of Ca2＋. Additionally, by studying the change of structure parameters, it was concluded that an external electric field can enhance the hydration between Ca2＋ and coordinated water molecules, and the alternating electric field is more effective in this respect.
