Study On Fast Generalized Predictive Control Algorithm For Typical Process Control Systems

Since the 1970's, the predictive controls have emerged as a powerful practical control technique especially in the process industry. Because of the adaptability to the complex system, predictive control can conquer some kinds of problem in the industrial process, which would be a handicap of the modern control theory faced. With the development of the microcomputer, the realization tools would be obtained; therefore, the predictive control algorithm has wide application and development.In the industrial system, however, for a typical industrial process system with simple structure, which almost was described as a first order or a second order with dead-delay. We think about generalized predictive control, a line of three typical control algorithms. It will make the huge computation, especially in the multiple systems and real time systems, so that the virtue of predictive control will not be embodiment. In order to cope with these basic problems, a new Fast Generalized Predictive Control (FGPC) algorithm is proposed in this paper, which is particularly effective for the typical industrial processes that can be regarded as the first-or second-order process model with a time-delay. The algorithm has good adaptive ability and robustness with low-cost computation, simple control structure, and PID-like formulation. Simulation studies demonstrate good behaviors.The whole thesis includes 5 chapters, and the main contents and conclusions are summarized as follows:In chapter 1, we review the basic theory and three typical algorithms of predictive control that included Model Algorithm Control, generalized predictive control and Recursive Horizon Control, some details of Generalized Predictive Control was specially described, we introduced the direct indirect algorithms and other kinds of algorithms. At finally, the application of in the typical industrial process and the software predictive control were presented.In chapter 2, we put forward the matrix computation and optimize strategy, and discuss the parameters and the limits of the standard generalized predictive control.In chapter 3, it is well known that a-first order or a-second order with dead-delay is always described in the typical loops of process control systems. A new Fast Generalized Predictive Control (FGPC) algorithm with low computation and simple structure that can be easily used in the typical loops of process control systems is presented in this chapter, and the controller parameter's number is little.In chapter 4, it has two different classes of model uncertainty (structured uncertainties and unstructured uncertainties. Based on the two uncertainties, we discussed the effect to the preference index that was caused by the uncertainties. In order to make sure the higher robustness, we get the range of two kinds of uncertainty (additive uncertainty and multiplicative uncertainty). The simulation results proved the inflection of robustness.In chapter 5.the conclusion of the thesis, our work and the future research and problem were presented.As a new model-computer control algorithm, it will be important and a promise project to enhance the research of practice application for generalized predictive control algorithm.