Parameter Optimization in Decentralized Process Control: A Program Package for Multivariable Industrial Regulators Design

Abstract

This paper deals with the computer aided optimization of the regulator parameters once any control structure has been selected in the general class of the linear control systems which can be described by any block diagram consisting of three basic elements: summing points, single input-single output dynamic or purely algebraic systems.The package consists of three programs working on a common data base: the “compiler program" which translates a topological-functional description of the regulator block scheme in data arrays suitable for the “parameter optimization program" which computes the optimal parameter values based on the mentioned control structure data, on a process linearized model and on the user's performance specifications and prepares the controlled system matrices used by the "simulation program" which provides standard transient simulations for a direct evaluation of the regulated process dynamic behaviour. The package is conceived so that a computer-unskilled process engineer is able to assign the control system description, to specify the performance requirements and to evaluate the control behaviour referring to familiar concepts.An application to the design of a thermoelectric power generation unit is also described: decentralized control systems are required in this case by the needs of maintaining simple control structures. The here proposed method makes possible a rational choice of the regulator parameters accounting for the actual interacting nature of the boiler-turbine process and fits with the recent trends of the control components technology which supplies powerfull control-oriented microcomputers for distributed data processing.