Delay-Dependent Robust Constrained Predictive Control Method for Uncertain Systems Under Unknown Disturbances

Abstract

The invention relates to a delay-dependent robust constraint predictive control method for an uncertain system with unknown disturbances. The method comprises the following steps: 1, establishing a state space model with an uncertain time-delay system; 2, transforming a constructed model into an expanded time-delay uncertain state space model; 3, designing a controller based on the above expandedmodel; and 4, solving the controller gain by using linear matrix inequality. The method has the advantages that the controller is designed by using the expanded time-delay uncertain state space modelso as to adjust the system state and output errors independently under the condition that a time lag exists, thereby providing more freedom of adjustment; the controller gain of the system is solved by using a new, less conservative and relatively simple expanded model based on a LMI-form delay-dependent stability condition so as to reduce the controller's conservativeness; the H-infinity performance index is introduced into the controller design to overcome any bounded interference and reduce control cost.

Description

technical field [0001] The invention belongs to the field of advanced control of industrial processes, and in particular relates to a time-delay-dependent robust constraint predictive control method for uncertain systems under unknown disturbances. Background technique [0002] With the rapid development of modern industry, the social demand for industrial products is increasing day by day, the scale of automatic control system is gradually expanding and the complexity is increasing, but the requirements for product quality and system performance are becoming increasingly strict, which will inevitably require production equipment to operate on the "card edge" "Under the conditions. Therefore, how to ensure system reliability and security and improve system performance is an open problem. In actual industrial processes, most processes, especially petrochemical processes, have uncertainty and time-varying time-delay, and are affected by input-output constraints and external d...

AI Technical Summary

Problems solved by technology

The previous technology or method used to extend the time-delay into the model to transform the problem with time-delay into a problem without time-delay, but this method greatly expanded the dimension of the model, thereby increasing the amount of calculation

In addition, there are also time-delayed models directly, but some slack variables need to be introduced, which increases a certain degree of conservatism.

[0003] At present, the industrial process for the liquid level of the three-capacity water tank system has characteristics such as uncertainty, unknown disturbance, time-varying time-delay, and input-output constraints. The controller designed by the existing technology and method has a high amount of calculation and A certain degree of conservatism, which will inevitably increase the calculation burden of the three-capacity water tank control system and reduce the performance of the system

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