Catalog ST PCS 7.1 - September 2005

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Advanced Process Control
INCA: Model-predictive multi-variable controller
■ Overview
Multivariable controller with integral optimization procedure
■ More information
Common control concepts in the processing industry today are
still almost exclusively based on PID controllers and also include IPCOS
manual intervention by the plant operator. In processes with
complex dynamics, linked process variables or limitations, PID Tel.: +32 1639 3083
controllers are overstretched.
Fax: +32 1639 3080
If a process should be operated close to the capacity limit, while E-mail: info@ipcos.com
at the same time minimizing waste and assuring the required
quality, the consideration of these precise boundary conditions
in the controller strategy is absolutely essential.
Additional information is available in the Internet under:
Additional weak spots are product or load changes which are
generally carried out partly or completely by the plant operator.
This causes variations which prevent optimum quality being
maintained at all times.
By carefully applying advanced modern control procedures http://www.ipcos.com
(Advanced Process Control, APC), the processing industry has
real leverage available for reducing costs and increasing quality.
Of all the modern control procedures, Model Predictive Control
(MPC) has emerged as the most suitable approach in numerous
applications. MPC simplifies the handling of complex plant dynamics,
permits the early elimination of faults, takes into consideration
the plant limitations and allows for complex process
control strategies.
The use of Advanced Process Control extends SIMATIC PCS 7
with the function of "process optimization". This creates a link
between the planning and scheduling functions of the execution
level and the process control functions of the control level.
INCA
This procedure is also used by INCA © , a multi-variable controller
of the latest generation. INCA differs from classic MPC controllers
due a series of functional extensions. Modern modeling methods,
bumpless switching between different models (multi-model
handling), expansions for batch processes, non-linear
predictions, and a high quality of control are setting new standards
and enable plant-wide optimization as well as the control
of non-linear processes.
The INCA (or GlassExpert) software itself runs on a separate PC
under the Windows NT/2000/XP operating system.
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Siemens ST PCS 7.1 · September 2005
■ Application
INCA for the glass industry
Preconfigured solutions based on INCA are available specially
for the glass industry. The GlassExpert © product series currently
comprises:
• "TubingExpert"
for dimensioning control of glass tubes
• "ProfileExpert"
for temperature profile control in glass channels
• "MeltingExpert"
for floor and atmosphere temperature control in glass melting
ends.
INCA for the chemical industry, application examples
• Ammonia plants
- Increase in throughput by up to 1%
- Increase in steam export by up to 1%
- Reduction in specific gas consumption by up to 1%
- Increased plant availability
- Less sensitive to changes in gas condition.
• Polymer plants
- More flexible operation (faster change of product)
- Production on request.