Synthesis Of Process Control Systems Research Articles

On the Role of Material Balances in the Synthesis of Overall Process Control Systems

Abstract The synthesis of control systems for overall processes remains a challenge. Whilst a number of automated approaches have been explored academically, in practice systems are mainly synthesised using experience and intuition in conjunction with dynamic simulation software. An approach is presented in this paper for the systematic synthesis of overall process control systems which is simple, practical and appropriate for use at the undergraduate teaching level. Many potential problems can be identified and avoided in the synthesis of process control systems by ensuring that the control system can maintain a steady-state control of the overall mass, the mass of the individual components and, where necessary, multiple phases. Processes with recycles are vulnerable to process control problems when the overall mass balance of the system containing the recycle is not correctly managed. This can be overcome by self-regulation (perhaps involving process design changes) or by changing the structure of the control system. Achieving and maintaining the material balance are the main purposes of the majority of controllers in most chemical processes. Without robust delivery of material balance control, higher level control objectives (such as quality controls) are unlikely to be met reliably. This paper presents a step-wise approach to the synthesis of overall process control systems that avoids many potential problems by identifying which process parameters can be manipulated to achieve the intended process mass balance and designing the control structure accordingly.

СПРОЩЕНА МАТЕМАТИЧНА МОДЕЛЬ ПРОЦЕСУ ГРАФІТУВАННЯ ВУГЛЕЦЕВИХ ЕЛЕКТРОДІВ

Production of carbon electrodes characterized by considerable resource and energy consumption, so important is the task of improving the efficiency of production through the introduction of optimal modes of its component processes. Developed and studied a simplified mathematical model of carbon electrodes graphitization, which differs from the known models almost zero time to calculate it. Constructed simplified mathematical model allows increasing effectiveness research process temperature control graphitization carbon electrodes by reducing the time a study to determine the temperature at any point in the process. Research conducted simplified models accuracy by comparing the temperature values calculated by these models, with temperatures calculated for the original complex model, which in this case is regarded as experimental data. As a result, a simplified mathematical model can be used for the synthesis of process control systems, as well as in the control system real time.

Simulation Models in Computer-Aided Design and Control Systems for Steel-Making Industry

The paper treets general principles underlying in the construction of simulation models employed in coordinated joint technology, facilities and control subsystems design. Algorithmic and software means are described which realize the developed simulation models. Some real life examples are given of the use of these means in CAD systems for steel-making industry. As simulation technology and software means receive further development an increasing number of algorithms is used for analysis and synthesis of process control systems. A significant part of these efforts may go in parallel with the design of process schemes and facilities. Simulation models intended to apply this approach to steel-making industries feature certain specifics described in the paper.

Structural sensitivity analysis in the synthesis of process control systems

A new approach to the synthesis of process control systems is formulated within the framework of internal model control (or inferential control, model reference scheme) whereby the fundamental limitations to perfect control which are inherent to the structure of a control system can be systematically analyzed. A structural sensitivity analysis and a screening strategy are developed to assess the control quality offered by different control systems. A key feature of the proposed analysis procedure is that it allows the designer to consider the realization of the internal model controller subject to structural constraints. Further, new plant invertibility conditions and various indicators to measure invertibility are derived and used throughout the synthesis. Finally a fluid catalytic cracker example is given to illustrate the power and the utility of the methodology.

Computer-aided synthesis of process control systems

Computer-aided synthesis of process control systems

A Logical Structure for Process Control System Synthesis

The synthesis of process control systems is placed in a series of process design activities which involve the basic process design and the establishment of plant operation strategy. For a given preliminary process scheme, a systematic procedure is presented for the synthesis of process control systems that contributes to complete process flow diagrams by adding information on process control systems. An illustrative example shows the usefulness of the proposed logical framework.

Synthesis of Process Control Systems

A systematic logical procedure for the synthesis of control systems for processes is presented. The approach is based on a causal modeling of processes, represented by the cause-and-effect graph. Control systems are generated by propagating the constraint variable on the cause-and-effect graph of the process. The method is capable of providing alternative designs for process control systems.