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A Graphical Language for Batch Control

Johnsson, Charlotta LU (1999) In PhD Theses TFRT-1051.
Abstract (Swedish)
Popular Abstract in Swedish

Denna avhandling presenterar ett grafiskt programmeringsspråk och dess användning vid styrning av satsvisa processer.



Arbetet i avhandlingen kan delas upp i två delar:



- utveckling av ett grafiskt programmeringspråk ämnat för implementering av styrsystem för sekventiella processer. Detta språk har fått namnet Grafchart.



- uppvisa hur recept-baserad styrning av satsvisa processer kan representeras och implementeras i Grafchart.



Grafiska programmeringspråk har många fördelar jämfört med textbaserade språk. De grafiska språken tillåter att programmet skriv i en form som likar den som människor använder vid modellering av... (More)
Popular Abstract in Swedish

Denna avhandling presenterar ett grafiskt programmeringsspråk och dess användning vid styrning av satsvisa processer.



Arbetet i avhandlingen kan delas upp i två delar:



- utveckling av ett grafiskt programmeringspråk ämnat för implementering av styrsystem för sekventiella processer. Detta språk har fått namnet Grafchart.



- uppvisa hur recept-baserad styrning av satsvisa processer kan representeras och implementeras i Grafchart.



Grafiska programmeringspråk har många fördelar jämfört med textbaserade språk. De grafiska språken tillåter att programmet skriv i en form som likar den som människor använder vid modellering av problem. Ytterligare en fördel är möjligheten att utnyttja färger och animering för att ge en klar och intuitiv bild av vad som sker då programmet exekverar. Grafchart bygger på Grafcet och Petri nät samt ideer vanligt förekommande i objekt-orienterad programmering. Detta har gett språket en intuitiv syntax och möjlighet till formell analys. Grafchart har definierats formellt samt implementerats i G2, en industriell objekt-orienterad plattform.



Det hittills främsta användningsområdet för Grafchart är strukturering av recept för styrning av satsvisa processer (satsvisa processer tillhör gruppen av sekventiella processer). Satsvisa processer är vanligt förekommande inom kemi-, livsmedels- och läkemedelsindustrin. Instruktionerna för hur processen ska styras kallas för recept. Ett flertal olika exempel på hur recepten kan struktureras presenteras i avhanlingen. Denna del av arbetet har noggrant följt de riktlinjer som finns i den nya internationella standarden för satsvisa processer. I avhandlingen presenteras även en metod som kan användas för att analysera recepten med avseende på låssituationer (blockeringar). Låssituationer kan uppkomma om utrusningen i anläggningen bokats på ett felaktigt sätt. (Less)
Abstract
In this thesis a graphical language for sequential control is presented and its application to batch control is examined and discussed. The name of the language is Grafchart. Its main feature is that it makes it possible to express complicated control problems in a compact and intuitive manner.



Grafchart exists in two versions; a basic version and a high-level version. The basic version was available when the work presented in this thesis started. The basic version of Grafchart is mainly based on Grafcet, i.e., it has a clear and intuitive syntax. In addition to this it has support for parameterization and methods and message passing as well as extended facilities for exception handling. The high-level version of... (More)
In this thesis a graphical language for sequential control is presented and its application to batch control is examined and discussed. The name of the language is Grafchart. Its main feature is that it makes it possible to express complicated control problems in a compact and intuitive manner.



Grafchart exists in two versions; a basic version and a high-level version. The basic version was available when the work presented in this thesis started. The basic version of Grafchart is mainly based on Grafcet, i.e., it has a clear and intuitive syntax. In addition to this it has support for parameterization and methods and message passing as well as extended facilities for exception handling. The high-level version of Grafchart takes the concepts of the basic version one step further. The concepts of object tokens and multi-dimensional charts are introduced. These features are inspired by high-level Petri nets and constructs from object-oriented programming languages.



The main application area of Grafchart is batch control. In the thesis it is shown how Grafchart can be used for recipe structuring and recipe analysis. By using the features of Grafchart in various ways, recipes can be given different structures with different advantages and disadvantages. All structures comply with the international batch standard IEC 61512 (also refered to as ISA S88.01). To test and evaluate the different recipe structures, a real-time batch plant simulation platform was used. The batch recipe structures can be combined with resource allocation and a visualization of the allocation is thereby achieved. By transforming the recipes into an equivalent Petri net structure, formal analysis methods that exist for Petri nets can be used to look for possible deadlock situations.



Several commercial batch control systems exist today. They all have a similar approach to recipe structuring, resource allocation and user presentation. The advantages of using Grafchart compared to some of these systems, regarding these features are presented in the thesis. A toolbox implementation of Grafchart exists. It is implemented in G2, an object-oriented programming environment. G2 is also an industrial environment, this makes the toolbox and the results of this thesis directly usable in industry. (Less)
Please use this url to cite or link to this publication:
author
opponent
  • Professor Dr.-Ing. Engell, Sebastian, University Dortmund, Germany
organization
publishing date
type
Thesis
publication status
published
subject
keywords
Automation, Batch Recipes, Batch Processes, Sequential Control, Grafcet, Petri nets, robotics, control engineering, Automatiska system, robotteknik, reglerteknik
in
PhD Theses
volume
TFRT-1051
pages
290 pages
publisher
Department of Automatic Control, Lund Institute of Technology (LTH)
defense location
Room M:E, M-building, Lund Institute of Technology
defense date
1999-03-25 10:15
ISSN
0280-5316
language
English
LU publication?
yes
id
cf023869-ac85-4f48-bff2-719f0d5ccf31 (old id 19349)
date added to LUP
2007-05-24 14:29:29
date last changed
2016-09-19 08:44:56
@phdthesis{cf023869-ac85-4f48-bff2-719f0d5ccf31,
  abstract     = {In this thesis a graphical language for sequential control is presented and its application to batch control is examined and discussed. The name of the language is Grafchart. Its main feature is that it makes it possible to express complicated control problems in a compact and intuitive manner.<br/><br>
<br/><br>
Grafchart exists in two versions; a basic version and a high-level version. The basic version was available when the work presented in this thesis started. The basic version of Grafchart is mainly based on Grafcet, i.e., it has a clear and intuitive syntax. In addition to this it has support for parameterization and methods and message passing as well as extended facilities for exception handling. The high-level version of Grafchart takes the concepts of the basic version one step further. The concepts of object tokens and multi-dimensional charts are introduced. These features are inspired by high-level Petri nets and constructs from object-oriented programming languages.<br/><br>
<br/><br>
The main application area of Grafchart is batch control. In the thesis it is shown how Grafchart can be used for recipe structuring and recipe analysis. By using the features of Grafchart in various ways, recipes can be given different structures with different advantages and disadvantages. All structures comply with the international batch standard IEC 61512 (also refered to as ISA S88.01). To test and evaluate the different recipe structures, a real-time batch plant simulation platform was used. The batch recipe structures can be combined with resource allocation and a visualization of the allocation is thereby achieved. By transforming the recipes into an equivalent Petri net structure, formal analysis methods that exist for Petri nets can be used to look for possible deadlock situations.<br/><br>
<br/><br>
Several commercial batch control systems exist today. They all have a similar approach to recipe structuring, resource allocation and user presentation. The advantages of using Grafchart compared to some of these systems, regarding these features are presented in the thesis. A toolbox implementation of Grafchart exists. It is implemented in G2, an object-oriented programming environment. G2 is also an industrial environment, this makes the toolbox and the results of this thesis directly usable in industry.},
  author       = {Johnsson, Charlotta},
  issn         = {0280-5316},
  keyword      = {Automation,Batch Recipes,Batch Processes,Sequential Control,Grafcet,Petri nets,robotics,control engineering,Automatiska system,robotteknik,reglerteknik},
  language     = {eng},
  pages        = {290},
  publisher    = {Department of Automatic Control, Lund Institute of Technology (LTH)},
  school       = {Lund University},
  series       = {PhD Theses},
  title        = {A Graphical Language for Batch Control},
  volume       = {TFRT-1051},
  year         = {1999},
}