| Hot blast stove is an important supporting equipment of blast furnace iron making,and it is the key aspect of the energy consumption in the entire blast furnace iron making process.It is beneficial to improve the operation efficiency and save energy when a reasonable control scheme of the hot blast stove system is designed.However,there are so many difficulties which need to solve to apply advanced control in practical process.For the sake of economic and security considerations,we have established a semi-physical simulation platform for hot blast stove in this paper.The platform consists of two parts,real PLC controller and virtual hot blast stove,the platform aims to provide a convenient environment for the research of new control methods and process detection methods.This paper mainly contains the following several parts:(1)The establishment of hot stove model.First of all,simplified heat transfer processes in the hot blast stove according to the actual running status of hot blast stove.Then,the unsteady heat transfer model of the regenerator is established,based on gas flow equation,gas heat balance equation and heat conduction equation.Thirdly,the discrete equation of the model is obtained by finite difference method.At last,the change of temperature in the hot blast stove with time and space,and the distribution of the temperature in the height of the heat storage body are obtained,after simulation program is written based on the C language.Due to the difficulty of obtaining some key physical parameters in the mechanism model and the error between the model and the actual data is large,BP neural network was used to model.After the transfer function,training parameters,the number of nodes in each layer are determined,the change of the vault temperature and the temperature of the flue gas with time is established based on the actual operating data of the hot blast furnace,including gas flow,air flow,pressure of each pipe,dome temperature,flue gas temperature.The accuracy of the new model is better than that of the previous model.(2)Design of hot blast stove semi-physical experimental platform.The semi-physical experimental platform of hot-blast stove consists of virtual controlled object,monitoring system and process control system.The virtual controlled object that is hot stove model,is programmed by Matlab software.The monitoring system can monitor and display the running state of the whole experimental platform in real time and archive the running data.The process control system is real hardware part of the experimental platform.It consists of real PLC controller and operating element.OPC communication is used between the virtual object and the monitoring system,between control system and monitoring system.(3)Simulation research in semi-physical experimental platform.According to the characteristics of hot air furnace object,the fuzzy control strategy of top temperature and smoke temperature is designed.The fuzzy control program is programmed in the PLC controller,and the control experiment is carried out by using the simulation model as the object.The simulation results show that the simulation platform has the conditions to carry out the research on the control method of hot blast stove. |
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