Abstract
Dynamic simulation can be used e.g. for operator
training, automation design and automation testing
purposes. For these applications, a flexible connection
between a process simulator and distributed control
system (DCS) is of great importance. In operator
training, it is practical to use the same man machine
interface as in the real plant, i.e. the user interface
of the DCS, and the same control schemes so that operator
can have exactly the same touch to the process as with
the real process. Compared to the effort of emulating the
graphics of the control system and re-configuring
automation solutions for the simulator, this means
immense savings. In automation design and testing, there
is a need for rapidly testing control strategies and
implementation against a simulation model by graphically
connecting control variables and measurements to the
process model.
In this paper, a new framework of connecting automation
domain applications is introduced. A case study where
dynamic process simulator is connected to the DCS is
described, and further requirements of the co-operation
between control systems and process simulators are
discussed.
The framework is based on a new software component, AIC
(Application Item Cross Connector) by the aid of which
OPC servers of different vendors can be connected
together. Through AIC one can connect to two different
OPC servers, browse the data items in both servers and
create joints between the data items. By giving joining
rules, the user can specify the properties of a joint
such as frequency, direction, data type, dead band, gain
and offset. After the joint is formed, AIC handles the
data transmission between the applications. Load and save
functions are also provided for, so that the
configuration data can be stored into the database. AIC
is based on OPC standard 1.0a. An easy to use graphical
user interface has also been built for the component.
In the case study presented in this paper, the new
communication scheme is bench marked by a test system
where the OPC servers of a DCS and a dynamic process
simulator are connected using AIC. A process model is
controlled by using a corresponding automation
application in DCS.
The framework sets new requirements for the DCS. The most
important of these are the capability to save and load
the state of the system, to freeze it if needed, and to
synchronize the simulator and the DCS. The save and load
functionalities are essential for the co-operation with
the simulator. Snapshots can be taken from the simulator
very easily, so there has to be a way to do the same for
the corresponding state in the DCS. These requirements
and how to extend current interfaces to meet the needs
are also discussed in this paper.
Original language | English |
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Title of host publication | TAPPI 99 ‘Preparing for the next millennium |
Place of Publication | Atlanta |
Publisher | TAPPI Press |
Pages | 329-337 |
ISBN (Print) | 0-89852-734-1, 978-0-89852-734-6 |
Publication status | Published - 1999 |
MoE publication type | B3 Non-refereed article in conference proceedings |
Event | 1999 TAPPI Process Control, Electrical and Information Conference - Atlanta, United States Duration: 1 Mar 1999 → 4 Mar 1999 |
Conference
Conference | 1999 TAPPI Process Control, Electrical and Information Conference |
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Country/Territory | United States |
City | Atlanta |
Period | 1/03/99 → 4/03/99 |