Prediction control system and method for polyethylene quality index system

Abstract

The invention relates to a prediction control system and method for a polyethylene quality index system. The method comprises the following steps of establishing a state space model of the system by using the Hammerstein model; linearizing the state space model by using the inverse function and the polytopic description method; sending the trigger information to the controller when there is data packet dropout; extracting a corresponding prediction model of the data packet dropout environment by a controller; using the optimal performance index function to online solve the infinite time domain optimization problem with a free control effect to obtain the control sequence of the next period of time, and exerting the first control sequence on the controlled object; and repeating the above steps. The invention adopts the strategy of real-time optimization. When there is data packet dropout, the controller in the networked prediction control module can propose the prediction model corresponding to the packet dropout environment according to the situation of data packet dropout, so as to compensate the control deviation caused by the data packet dropout and to solve the data packet dropout problem in the network environment.

Description

technical field [0001] The invention belongs to the technical field of polyethylene quality control, and in particular relates to a predictive control system and method of a polyethylene quality index system. Background technique [0002] The traditional chemical industry represented by polyethylene is an industrial field in which our country promotes industrialization with informationization and takes a new road of industrialization. It is one of the main directions for transformation and upgrading to realize networked control of the entire production process. This networked control system that connects devices such as sensors, controllers and actuators distributed in different geographical locations through the network can realize resource sharing among devices and facilitate remote operation. It is a new type of fully distributed real-time feedback control mode. However, the data packet loss problem caused by the inherent properties of the network restricts the populariz...

AI Technical Summary

Problems solved by technology

However, the conventional predictive control methods currently used in the process industry cannot deal with the problems of data packet loss that will inevitably be encountered when sensor signals and controller signals are transmitted in a network environment.

If the industrial process using conventional predictive control is directly placed in the networked control mode, it will definitely have an adverse effect on the control quality of the system, and even pose a threat to safe production in serious cases.

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