Study On Decoupling Control System Of Super Bogie-hearth Resistance Furnace

Resistance furnace is electric heating equipment used in industrial production.It is widely used in metallurgy, machinery, building materials and so on.With the increasing of the heat treatment qulity for pressure vessels, the requirements of the furnace temperature control have been become higher and higher.However, it is difficult to establish a precise mathematical model because the resistance furnace temperature is the object that is multivariate, strong coupling and large inertia.Therefore, the great deal of uncertainty that is brought by temperature control has seriously affected the quality of products.Firstly, the paper comprehensively analyzes the present situation, development trends and problems about the application of temperature control of large bogie-hearth resistance furnace.Secondly, through exhaustive and systemic theory analyse for heat treatment process in the large bogie-hearth resistance furnace , aim at the difficult problem that the temperature has serious big lagging, and strong couple, a kind method of PID neural network decoupling control, combined with the functions of stirring fans and the distribution of heated districts technology, is adopted in the paper, it successfully solves the coupled problem among the temperature of resistance furnace, makes the system have the better decoupling properties.According to the request of heat treatment, a automation system has been developed to test, control and manage based on field bus technology. The system is composed of two layers of computer control structure, basic automation is completed to realize the logic control and accomplish the operation of the temperature control by Mitsubishi PLC. Supervisor fulfills many functions such as configuration, supervision, alarm, table, etc.The resistance furnace actual results show that the system is high precision, reliabity and stability. The system can meet the request of super heat treatment equipment completely.The successful applications of the system in the super heat treatment equipment can also give valuable experience for manufacturing super heat treatment equipment and alteration in other field.Finally, the summary is made to the work , and the author looks forward to the work direction in the future.