Uncoupling control method for double-inputting and double-outputting system

Abstract

An industrial process control technology field two-input-output system's decoupling control method, it lets the reverse decoupling structure's decoupling machine and the controller into one decoupling control machine, and it forms the unit feedback control structure. By adding the compensation item, it can eliminate decoupling controller machine's unstable factors. It designs the decoupling controller machine's sub-controller base on the inner module theory, then the final decoupling control machine is almost the easy implement PID / PI controller. When has the actual operating control, the first is deduce the controller parameter's lowest borders which can meet the LuBang stability condition. Then on the base of this border minimum, separately enlarge every loop's control parameter monotonously until gain the system mark capability which complies with the project's requirements. The control method structure of this invention is simple and easy to achieve, and has wide applicability and is easy to operate, it can quickly accurate tuning control parameters and makes the closed loop control system meet the LuBang stability requirement.

Description

technical field [0001] The invention relates to a method used in the technical field of industrial process control, in particular to a decoupling control method for a dual-input and dual-output system. Background technique [0002] The double-input and double-output process is a common multivariable process in chemical production, and in order to facilitate operation and control, many high-dimensional multivariable processes are usually decomposed into several double-input and double-output subsystems for processing in practice. In order to solve the coupled control problem of a dual-input dual-output system, traditional decoupling methods, such as ideal decoupling, simple decoupling, and reverse decoupling, are to decouple a multivariable system with coupling into multiple univariate systems, and then The control method of the single variable system is applied to realize the multi-loop control. Because it can achieve the ideal decoupling effect, and each closed loop works ...

AI Technical Summary

Problems solved by technology

However, in practical applications, these three traditional decoupling methods have different defects: the decoupler of ideal decoupling is more complicated and difficult to realize; the decoupler of simple decoupling is easier to realize, but the decoupled decoupler The form of the controlled object is more complicated, which brings inconvenience to the controller design; although the reverse decoupling has both the simple decoupler and the decoupled controlled object, due to the limitation of the system stability conditions, some The stable object of the cannot be directly controlled using this control structure

This detection method requires trial and error, is not easy to implement online, and cannot quickly select controller parameter values ​​that satisfy the robust stability of the system.

[0004] Found through literature search to prior art, Wade, H.L. people such as " ISA Transactions " (ISA magazine) (No. 1 issue in January, 1997, total volume 36, pages 3-10) " Inverted decoupling : a neglected technique” (reverse decoupling: a neglected technology), this paper proposes a control system design method based on reverse decoupling, the input signal of the controlled process is used as the input signal of the decoupler, Feedback the output signal of the decoupler to the output terminal of the controller. This method can achieve better decoupling performance in theory. model, the plant with right-half-plane zeros is not discussed

Moreover, this decoupling method is constrained by the stability conditions and is not suitable for all stable two-input two-output linear systems

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