Coordinated Control Of Human-Like Intelligent Control Based On Internal Model Structure

Internal model control (IMC) is successful in controlling the plant with large time delay. It has good steady-state performance, good robustness, simple structure, only a few tuning parameters and is easy to design and tune. Adjustable parameters of internal model controller decide the system performance, but tuning the system response is trade-offs between stability and response speed by control strategies and characteristics of system structure. Human-like intelligent control is a crossing field of various subjects including automatic control, artificial intelligence and computer science. It simulates the rules of human being' s intelligent activity while performing information processing, control and decision-making, and researches the system of engineering control and information processing with human-simulated intelligence. Applying intelligence character of human-like intelligent control and combining excellence of internal model control, a new controlling strategy of coordinated control of Human-Like intelligent control based on internal model structure is proposed. It results in designing unification between stability, veracity and response speedBased on the analysis of internal model control and human-like intelligent control, the method of fixed parameters coordinated controlof Human-Like intelligent control based on internal model structure is proposed. The method of counteracting is applied to internal model controller in order to assure the performance of steady-stage; design of adjustable parameters of internal model controller has to take into account of the smoothness and speed of the response , as well as the robustness. Therefore its tuning ability is limited. Coordinated controller is designed by using the idea of Human-Like intelligent control. Inputs of coordinated controller use those signals of system error, the change rate of system error and the change rate of modeling error. Coordinated controller recognizes process states on-line by using the qualitative and quantitative methods and adjusts plant input by applying multi-mode control strategy in transient process. When system error is below the bound of steady-stage error, output of coordinated controller is zero. So the system steady-stage performance is assured only by internal model controller. The method improves the performance of dynamic response and realizes the unification between the stability and response speedCoordinated control of Human-Like intelligent control with fixed parameters inevitably lead to the system performance not lying in the optimal mode if plant parameters change. So it affects the robustness and disturbance rejection performance in a certain extent. In order to conquer those shortages, a method of adaptive coordinated control of Human-Like intelligent control based on internal model structure is proposed. Adaptive coordinated control of Human-Like intelligent control based on internal model structure is constructed by using those variables including error, modeling error, change rate of error and change rate of input of the controlled plant. Human-Like intelligent control includes running level, parameters adjusting level and task-adapting Level. It has the structure characteristic of hierarchical intelligent control. The control system realizes the independent design among of responsespeed, stability, robustness and disturbance rejection performance.For the first-order and second-order plants with larger time delay, the simulation results show that the two kinds of methods are effective. Both methods improve the robustness and disturbance rejection performance of the control systems.