(712b) A Scheduling Perspective on the Monetary Value of Improving Process Control
During steady-state operation, an effective control system minimizes the variability of the controlled variables, such that the process can be operated close to the constraints on those states, which normally translates to higher profits. The most common approach for quantifying the monetary value of any proposed control system has therefore been through performance functions that define profit as a function of the distance between a process value and its operational limit . In transient operation, an effective control system is one that minimizes the transition time between operating points, and limited work has been done on quantifying the monetary value of control systems in the context of transient operation.
In todayâs fast-changing markets, transient operation has become ever-more relevant, and thus there have been many efforts towards integrating the dynamic process control calculations within process scheduling frameworks. This integration has been shown to yield significant economic benefits . However, the problem of how to quantify the monetary value of a particular control technology across the horizon of a production schedule remains open.
In this work, we posit that the monetary value of a particular control system can be evaluated by defining control performance metrics and quantifying the change in a production scheduling profit objective value as the performance metric varies. We arrive at an explicit expression that is applicable to any production scheduling problem, and illustrate our methodology for several case studies.
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