In industrial automation projects, advanced control strategies are often defined in the early stages—either by the client or the solution provider. However, regardless of the source, these strategies must remain flexible. Evaluating a project solely based on the initial control structure is not only unrealistic but may also lead to performance issues.
From Initial Concepts to Functional Design (FDS)
At the beginning of the project, advanced control concepts are typically based on preliminary surveys. These concepts might be “correct” in theory, but they often lack the practical depth required for real-world implementation. After on-site investigation, a more detailed Functional Design Specification (FDS) is prepared, expanding on the initial technical agreement.
Yet even the FDS is not the final word. As the project progresses, the control strategy outlined in the FDS must be revised in response to actual process behaviors, control loop performance, and improved process understanding.
Dynamic Nature of Advanced Control
Even after commissioning advanced controllers, it’s common to:
Modify internal models,
Reconfigure controller structures, and
Reassign control variables.
Engineers’ understanding of the plant evolves over time. Although ideally, the control structure would be finalized before implementation, practical constraints (e.g., limited knowledge, changing process conditions, or hardware limitations) make this difficult.
Without a continuous improvement mechanism and a willingness to revise the strategy, even the most advanced controllers will fail to deliver long-term benefits.
Maintenance Phase and Strategy Evolution
After project acceptance and the handover of a detailed FDS, new operational data may require further changes—especially as process conditions change. Control strategies must evolve accordingly.
To reduce the frequency of complete redesigns, designing for flexibility—such as including multiple variables with selective activation—can be an effective approach.
Conclusion
Advanced control systems solve real problems, but only when treated as dynamic tools. The strategy must evolve alongside:
Process changes,
Engineering insights, and
Operational feedback.
In summary: change is not a flaw—it’s a fundamental requirement for sustainable performance in advanced process control.