LI Yan
,
MAO Zhi-zhong
,
WANG Yan
,
YUAN Ping
,
JIA Ming-xing
钢铁研究学报(英文版)
In electric arc furnace smelting, electrode regulator system is a key link. A good electrode control algorithm will reduce energy consumption effectively and shorten smelting time greatly. The offline design online synthesis model predictive control algorithm is proposed for electrode regulator system with input and output constraints. On the offline computation, the continuum of terminal constraint sets will be constructed. On the online synthesis, the time-varying terminal constraint sets will be adopted and at least one free control variable will be introduced to solve the min-max optimization control problem. Then Lyapunov method will be adopted to analyze closed-loop system stability. Simulation and field trial results show that the proposed offline design online synthesis model predictive control method is effective.
关键词:
electrode regulator system
,
model predictive control
,
time-varying terminal constraint set
,
Lyapunov stability
,
linear matrix inequalities (LMIs)
CHEN Yin-li
,
WANG Yan
,
ZHAO Ai-min
钢铁研究学报(英文版)
Abstract： The precipitation kinetics of AlN and MnS in low carbon aluminium-killed steel was calculated. Transmission electron microscopy (TEM), energy disperse spectroscopy (EDS) and phase analyses have been used to investigate the morphology, compositions and particle size distribution of AlN and MnS precipitates in three positions of the coil. The particles of AlN and MnS precipitates in the ferrite region after coiling and distributes along and adjacent to the ferrite grain boundaries. The shapes of AlN are plate-like, the precipitates size is about 10 to 60 nm; the shapes of MnS are spherical, the precipitates size is about 200 to 600 nm. The precipitation behavior of AlN is sensitive to the isothermal temperature and holding time, the precipitation quantity and particle size distribution of AlN in different positions of coil are unequal.
关键词:
Key words: precipitation kinetics
,
morphology
,
low carbon steel
,
AlN
,
MnS
