Research On A Class Of Uncertain Dmc Method In Blast Furnace

Blast furnace is a multi-variable, large time delay, nonlinear and large noise system. The factors that affect the operation of blast furnace are too many, and the measurement is difficulty. Maintain a good and reasonable furnace temperature is a key factor for stable operation of blast furnace production, and is the direct assurance for blast furnace to achieve long life, high yield, high-quality, low consumption. The high furnace temperature will increase the coke, reduce the iron production and lead to occurrence of faults in blast furnace. The low furnace temperature will make blast furnace lack of reaction heat and even lead to blast furnace accident. Therefore, how to choose furnace temperature correctly and maintain furnace temperature stability has great significance to the iron making of blast furnace. How to predict and control the blast furnace temperature has become the core of blast furnace process control.In this article, on the basis of consulting a large number of domestic and international relevant documents, the development of the blast furnace temperature controlling is proposed firstly. Then through analyzing the blast furnace temperature controlling in depth and investigating dynamic matrix control algorithm and stair-like control, at the same time, fully considering the impaction of uncertainties in the process of blast furnace ironmaking, one kind of uncertain stair-like dynamic matrix predictive control algorithm for a class of tempreture in the blast furnace is proposed.The algorithm inherited the advantages of traditional DMC algorithm. The prediction model is established in case that the coal rate, blast volume and flow of cooling water are the control inputs, and the temperature is control output. The system's future output is gained using the prediction model. Carry out feedback correction by compared with errors between the observed values and the output values of prediction model. Then compared with the reference temperature to obtain optimal control rate and rolling optimization. At the same time, this algorithm, in the blast furnace temperature control system, introduced a stair-like control to solve the volume of optimal control and avoid the complex matrix operations in DMC algorithm. Finally, as the impaction of uncertainties exists in the process of blast furnace ironmaking, in order to ensure that the optimal control rate is solvable, admissible control set is introduced. Adjust the uncertainty parameters in admissible control set to make the temperature's predicted output value within the error range of±5°C . The result of simulating test shows that the predictive control algorithm can make a correct prediction of the current temperature, and has the advantages of good stability, which implies that this control approach is effective for improving the accuracy of the blast furnace temperature control. In addition, the man-machine interface of blast furnace temperature control system and its functions are introduced in this article.…………….